CAN CLOSING MACHINE

Abstract

A can closing machine (10) is operative to close standard gauge aluminum cans as well as lighter, weight reduced cans which have a lower column strength. Exemplary arrangements include a can closing machine that includes a turret (12) with a plurality of angularly spaced can closing stations (16). Each can closing station includes a lower chuck (44, 172) and an upper chuck (54). Can seaming rolls are operative to produce a continuous double seam (70) that join a can body (50) and a can lid (56) in sealed fluid tight relation. The machine is operative to precisely control the vertical velocity, position and momentum of the lower chuck and the can components supported thereon when engaging the upper chuck to reduce the risk of damage to can bodies and producing defective seams.

Claims

1. Apparatus comprising: a high speed can closing machine including: a rotatable turret, wherein the turret is rotatable about a turret axis in a first rotational direction, includes a plurality of angularly disposed can closing stations, wherein the can closing stations are positioned at a radially outer periphery of the turret, wherein each can closing station includes a lower chuck, wherein the lower chuck includes a can supporting platform, wherein the can supporting platform is configured to support a bottom end of a respective can body, wherein the can body houses can contained material, is rotatable about a chuck axis in a second rotational direction opposed of the first rotational direction, is selectively movable vertically relative to the turret, a lower chuck vertical actuator, wherein the vertical actuator is in operative connection with the lower chuck and is operative to cause selective vertical movement of the can supporting platform, an upper chuck, wherein the upper chuck is axially aligned with the chuck axis, is vertically immovable relative to the turret, is rotatable in the second rotational direction and in coordinated relation with the can supporting platform, is configured to engage a can lid, wherein the can lid is positioned in closing relation of a can opening at an upper end of the can body, wherein the upper end is axially opposed of the bottom end, first and second seaming rolls, wherein with the can bottom end engaged with the can supporting platform and the can lid engaged with the upper chuck, the first seaming roll is operative to engage an upper annular peripheral flange on the can body that extends in surrounding relation of the can opening and an annular peripheral portion of the can lid, and responsive at least in part to rotation of the can body and the can lid about the chuck axis, to cause in axial cross section the annular peripheral portion of the can lid to extend around the annular peripheral flange to produce a continuous annular peripheral can double seam, and the second seaming roll is operative to engage the seam after engagement with the first seaming roll, and responsive at least in part to rotation of the can body and can lid about the chuck axis, to cause radial compression of the seam and the seam to be fluid tight, wherein the machine is operative to cause the can closing station to receive the can body and can lid, the can lid and can body to be raised to engage the can lid and the respective upper chuck, and the can body and can lid to be joined by the fluid tight seam that is operative to close the can opening during less than one turret rotation, wherein the can closing machine is operative to cause the can lid to engage the upper chuck with combined vertical momentum of the lower chuck, the can body, the can lid and the can contained material that is not greater than 0.21 Ns.

2. The apparatus according to claim 1 wherein the turret rotates in the first rotational direction at a speed of at least 90 RPM, wherein each can closing station receives a respective can body that has a column strength of approximately 550 N, and the can closing machine is operative to produce fluid tight seams that close at least 1600 cans per minute.

3. The apparatus according to claim 1 wherein the turret rotates in the first rotational direction at a speed of at least 100 RPM, wherein each can closing station receives a respective can body that has a column strength of approximately 550 N, and the can closing machine is operative to produce fluid tight seams that close at least 1800 cans per minute.

4. The apparatus according to claim 1 wherein the lower chuck further includes a compression spring, wherein the compression spring extends axially and applies a force in aligned relation with the chuck axis, is positioned on the lower chuck operatively intermediate of the lower chuck vertical actuator and the can supporting platform, includes an axially lower spring end, wherein immediately after can lid and upper chuck engagement, the lower chuck vertical actuator is operative to cause the lower spring end to move upward at a constant velocity for at least 0.013 cm, wherein the can closing machine is operative to cause the can supporting platform to apply a linearly increasing force to the bottom end of the can body and to the upper chuck immediately after can lid and upper chuck engagement.

5. The apparatus according to claim 1 wherein the lower chuck further includes a compression spring, wherein the compression spring extends axially and applies a force in aligned relation with the chuck axis, is positioned on the lower chuck operatively intermediate of the lower chuck vertical actuator and the can supporting platform, includes an axially lower spring end, wherein immediately after can lid and upper chuck engagement, the lower chuck vertical actuator is operative to cause a lower spring end to move upward at a constant velocity, wherein the can closing machine is operative to cause lower spring end movement that causes the can supporting platform to apply a linearly increasing additional force with a maximum of less than 36 N to the bottom end of the can body and to the upper chuck immediately after can lid and upper chuck engagement.

6. The apparatus according to claim 1 wherein the lower chuck further includes a compression spring, wherein the compression spring extends axially and applies a force in aligned relation with the chuck axis, is positioned on the lower chuck operatively intermediate of the lower chuck vertical actuator and the can supporting platform, is preloaded to a force level of 355 N to 445 N prior to can lid and upper chuck engagement, wherein the can closing machine is operative to cause immediately after can lid and upper chuck engagement, the lower chuck vertical actuator to cause a lower spring end to move upward at a constant velocity, and the lower spring end movement to cause the can supporting platform to apply a linearly increasing additional force in addition to the preloaded force level, with a maximum of less than 36 N, to the bottom end of the can body and to the upper chuck.

7. The apparatus according to claim 1 wherein the vertical actuator is operative to cause the can lid to engage the upper chuck at an upward velocity in a range of 0.010 m/s to 0.015 m/s.

8. The apparatus according to claim 1 wherein the can closing machine is operative to cause the can supporting platform of each lower chuck to move between a lowered position in which the can lid is disposed vertically away from the upper chuck and a raised position in which the can lid is engaged with the upper chuck, wherein each can closing station further includes a knockout pad, wherein the knockout pad is aligned with the chuck axis, applies a vertically downward force opposing upward movement of the can lid and the can supporting platform intermediate of the lowered position and the raised position and while the can body and can lid rotate in the second rotational direction in engagement with the can supporting platform.

9. The apparatus according to claim 1 wherein the can closing machine is operative to cause the can supporting platform of each lower chuck to move between a lowered position in which the can lid is disposed vertically away from the upper chuck and a raised position in which the can lid is engaged with the upper chuck, wherein each can closing station further includes a knockout pad, wherein the knockout pad is aligned with the chuck axis, applies a vertically downward force of 145 N to 312 N opposing upward movement of the can lid and the can supporting platform intermediate of the lowered position and the raised position and while the can body and can lid rotate in the second rotational direction in engagement with the can supporting platform.

10. The apparatus according to claim 1 wherein the can closing machine is operative to cause the can supporting platform of each lower chuck to move between a lowered position in which the can lid is disposed vertically away from the upper chuck and a raised position in which the can lid is engaged with the upper chuck, wherein each can closing station further includes a knockout pad, wherein the knockout pad is aligned with the chuck axis, applies a vertically downward force of 222 N to 312 N opposing upward movement of the can lid and the can supporting platform intermediate of the lowered position and the raised position and while the can body and the can lid rotate in the second rotational direction in engagement with the can supporting platform and the turret rotates in the first rotational direction at least 5.

11. The apparatus according to claim 1 wherein the lower chuck further includes a chuck shaft, wherein the chuck shaft extends along the chuck axis, a chuck gear, wherein the chuck gear is in fixed operative connection with the chuck shaft, wherein an upper portion of the chuck shaft extends vertically above the chuck gear, a piston, wherein the piston extends in contacting surrounding relation of the upper portion of the chuck shaft, is in fixed rotational connection with the upper portion of the chuck shaft, is axially movable relative to the upper portion of the chuck shaft, and is in fixed operative connection with the can supporting platform, an annular upper sleeve, wherein the upper sleeve is in fixed operative connection with the turret, wherein the upper sleeve extends in contacting surrounding relation of the piston, and extends vertically below the can supporting platform, wherein the piston while in contacting relation with the upper portion of the chuck shaft and the upper sleeve is both rotationally and vertically movable relative to the upper portion of the chuck shaft and the upper sleeve.

12. The apparatus according to claim 1 wherein the lower chuck further includes a chuck shaft, wherein the chuck shaft extends along the chuck axis, a chuck gear, wherein the chuck gear is in fixed operative connection with the chuck shaft, wherein an upper portion of the chuck shaft extends vertically above the chuck gear, a piston, wherein the piston extends in contacting surrounding relation of the upper portion of the chuck shaft, is in fixed operative connection with the can supporting platform, and includes at least one radially extending axially elongated slot, wherein a respective pin extends radially through a respective axially elongated slot and operatively engages the piston and the upper portion of the chuck shaft, wherein the piston is in fixed rotational connection with the upper portion of the chuck shaft and while in contacting surrounding relation with the upper portion of the chuck shaft is axially movable relative to the upper portion of the chuck shaft, an annular upper sleeve, wherein the upper sleeve is in fixed operative connection with the turret, wherein the upper sleeve extends in contacting surrounding relation of the piston, and extends vertically below the can supporting platform, wherein the piston while in contacting relation with the upper sleeve is both rotationally and vertically movable relative to the upper sleeve.

13. The apparatus according to claim 1 wherein the lower chuck further includes a chuck shaft, wherein the chuck shaft extends along the chuck axis, a chuck gear, wherein the chuck gear is in fixed operative connection with the chuck shaft, wherein an upper portion of the chuck shaft extends vertically above the chuck gear, a piston, wherein the piston extends in contacting surrounding relation of the upper portion of the chuck shaft, is in fixed rotational connection with the upper portion of the chuck shaft, is axially movable relative to the upper portion of the chuck shaft, and is in fixed operative connection with the can supporting platform, a compression spring, wherein the compression spring extends in centered relation of the chuck axis and operatively intermediate of the piston and the upper portion of the chuck shaft, an annular upper sleeve, wherein the upper sleeve is in fixed operative connection with the turret, wherein the upper sleeve extends in contacting surrounding relation of the piston, and extends vertically below the can supporting platform, wherein the piston while in contacting relation with the upper sleeve is both rotationally and vertically movable relative to the upper sleeve.

14. The apparatus according to claim 1 wherein the lower chuck further includes a chuck shaft, wherein the chuck shaft extends along the chuck axis, a chuck gear, wherein the chuck gear is in fixed operative connection with the chuck shaft, wherein an upper portion of the chuck shaft extends vertically above the chuck gear, a piston, wherein the piston extends in contacting surrounding relation of the upper portion of the chuck shaft, is in fixed rotational connection with the upper portion of the chuck shaft, is axially movable relative to the upper portion of the chuck shaft, and is in fixed operative connection with the can supporting platform, a compression spring, wherein the compression spring extends in centered relation of the chuck axis and operatively intermediate of the piston and the upper portion of the chuck shaft, an annular upper sleeve, wherein the upper sleeve is in fixed operative connection with the turret, wherein the upper sleeve extends in contacting surrounding relation of the piston, and extends vertically below the can supporting platform, wherein the piston while in contacting relation with the upper sleeve is both rotationally and vertically movable relative to the upper sleeve.

15. The apparatus according to claim 1 wherein the lower chuck further includes a chuck shaft, wherein the chuck shaft extends along the chuck axis, a chuck gear, wherein the chuck gear is in fixed operative connection with the chuck shaft, wherein an upper portion of the chuck shaft extends vertically above the chuck gear, a piston, wherein the piston extends in contacting surrounding relation of the upper portion of the chuck shaft, is in fixed rotational connection with the upper portion of the chuck shaft, is axially movable relative to the upper portion of the chuck shaft, and is in fixed operative connection with the can supporting platform, a compression spring, wherein the compression spring extends in centered relation of the chuck axis and operatively intermediate of the piston and the upper portion of the chuck shaft, a spring adjusting screw, wherein the spring adjusting screw is in operative connection with the compression spring, extends in the piston, and is selectively axially positionable, whereby the spring adjusting screw enables selectively setting a preload force on the compression spring, an annular upper sleeve, wherein the upper sleeve is in fixed operative connection with the turret, wherein the upper sleeve extends in contacting surrounding relation of the piston, and extends vertically below the can supporting platform, wherein the piston while in contacting relation with the upper sleeve is both rotationally and vertically movable relative to the upper sleeve.

16. The apparatus according to claim 1 wherein the lower chuck further includes a chuck shaft, wherein the chuck shaft extends along the chuck axis, a chuck gear, wherein the chuck gear is in fixed operative connection with the chuck shaft, wherein an upper portion of the chuck shaft extends vertically above the chuck gear and a lower portion of the chuck shaft extends vertically below the chuck gear, a piston, wherein the piston extends in contacting surrounding relation of the upper portion of the chuck shaft, is in fixed rotational connection with the upper portion of the chuck shaft, is axially movable relative to the upper portion of the chuck shaft, and is in fixed operative connection with the can supporting platform, an annular upper sleeve, wherein the upper sleeve is in fixed operative connection with the turret, wherein the upper sleeve extends in contacting surrounding relation of the piston, and extends vertically below the can supporting platform, wherein the piston while in contacting relation with the upper portion of the chuck shaft and the upper sleeve is both rotationally and vertically movable relative to the upper portion of the chuck shaft and the upper sleeve, a slider, wherein the slider includes a cylindrical slider cavity, wherein the slider cavity is in centered relation with the chuck axis, wherein the lower portion of the chuck shaft extends in the slider cavity, at least one bearing, wherein the at least one bearing extends in the slider cavity and radially intermediate of the lower portion of the chuck shaft and the slider, whereby the chuck shaft is rotatable in the slider cavity, an annular lower sleeve, wherein the lower sleeve extends in contacting surrounding relation of the slider, and is in fixed operative connection with the turret, wherein while in contacting relation with the lower sleeve the slider is vertically movable relative to the lower sleeve.

17. The apparatus according to claim 1 wherein the lower chuck further includes a chuck shaft, wherein the chuck shaft extends along the chuck axis, a chuck gear, wherein the chuck gear is in fixed operative connection with the chuck shaft, wherein an upper portion of the chuck shaft extends vertically above the chuck gear and a lower portion of the chuck shaft extends vertically below the chuck gear, a piston, wherein the piston extends in contacting surrounding relation of the upper portion of the chuck shaft, is in fixed rotational connection with the upper portion of the chuck shaft, is axially movable relative to the upper portion of the chuck shaft, and is in fixed operative connection with the can supporting platform, an annular upper sleeve, wherein the upper sleeve is in fixed operative connection with the turret, wherein the upper sleeve extends in contacting surrounding relation of the piston, and extends vertically below the can supporting platform, wherein while in contacting relation with the upper sleeve the piston is both rotationally and vertically movable relative to the upper sleeve, a slider, wherein the slider includes a cylindrical slider cavity, wherein the slider cavity is in centered relation with the chuck axis, wherein the lower portion of the chuck shaft extends in the slider cavity, at least one bearing, wherein the at least one bearing extends in the slider cavity and radially intermediate of the lower portion of the chuck shaft and the slider, whereby the chuck shaft is rotatable in the slider cavity, an annular lower sleeve, wherein the lower sleeve extends in contacting surrounding relation of the slider, and is in fixed operative connection with the turret, wherein while in contacting relation with the lower sleeve the slider is vertically movable relative to the lower sleeve, wherein the lower chuck vertical actuator includes a cam roller, wherein the cam roller is mounted in journalled relation on the slider.

18. The apparatus according to claim 1 wherein the lower chuck further includes a chuck shaft, wherein the chuck shaft extends along the chuck axis, a chuck gear, wherein the chuck gear is in fixed operative connection with the chuck shaft, wherein an upper portion of the chuck shaft extends vertically above the chuck gear and a lower portion of the chuck shaft extends vertically below the chuck gear, a piston, wherein the piston extends in contacting surrounding relation of the upper portion of the chuck shaft, is in fixed rotational connection with the upper portion of the chuck shaft, is axially movable relative to the upper portion of the chuck shaft, and is in fixed operative connection with the can supporting platform, an annular upper sleeve, wherein the upper sleeve is in fixed operative connection with the turret, wherein the upper sleeve extends in contacting surrounding relation of the piston, and extends vertically below the can supporting platform, wherein while in contacting relation with the upper sleeve the piston is both rotationally and vertically movable relative to the upper sleeve, a slider, wherein the slider includes a cylindrical slider cavity, wherein the slider cavity is in centered relation with the chuck axis, wherein the lower portion of the chuck shaft extends in the slider cavity, at least one bearing, wherein the at least one bearing extends in the slider cavity and radially intermediate of the lower portion of the chuck shaft and the slider, whereby the chuck shaft is rotatable in the slider cavity, an annular lower sleeve, wherein the lower sleeve extends in contacting surrounding relation of the slider, and is in fixed operative connection with the turret, wherein while in contacting relation with the lower sleeve the slider is vertically movable relative to the lower sleeve, wherein the lower chuck vertical actuator includes a cam roller, wherein the cam roller is removably mounted in journalled relation on the slider intermediate of a pair of downward extending legs, wherein the slider includes an access opening, wherein the access opening extends along the chuck axis and intermediate of the legs, a removable shaft retainer, wherein the shaft retainer operatively releasably holds the shaft in vertically engaged relation with the slider, wherein the shaft retainer is accessible through the access opening.

19. The apparatus according to claim 1 wherein the lower chuck further includes a cam roller and a further cam roller, wherein the vertical actuator includes a lifter cam and a hold down cam, wherein the cam roller is in operative engagement with the lifter cam, and the further cam roller in operative engagement with the hold down cam.

20. The apparatus according to claim 1 wherein the lower chuck further includes a chuck shaft, wherein the chuck shaft extends along the chuck axis, a chuck gear, wherein the chuck gear is in fixed operative connection with the chuck shaft, wherein an upper portion of the chuck shaft extends vertically above the chuck gear, a piston, wherein the piston has an annular piston outer surface, wherein the annular piston outer surface has a piston outer diameter, includes an inner annular surface that extends in surrounding movably engaged relation of the upper portion of the chuck shaft, is in fixed rotational connection with the upper portion of the chuck shaft, is axially movable relative to and in engaged relation with the upper portion of the chuck shaft, and is in fixed operative connection with the can supporting platform, a compression coil spring, wherein the compression coil spring extends in centered relation of the chuck axis and operatively intermediate of the piston and the upper portion of the chuck shaft, and has a coil spring outer diameter, an annular upper sleeve, wherein the upper sleeve is in fixed operative connection with the turret, wherein the upper sleeve extends in surrounding movably engaged relation with the outer surface of piston, and extends vertically below the can supporting platform, wherein the piston while in contacting relation with the upper sleeve is both rotationally and vertically movable relative to the upper sleeve, wherein the lower chuck is configured such that when the bottom end of the can body that is axially centered on the can supporting platform a can downward facing bottom wall is in abutting relation with the can supporting platform, and the can downward facing bottom wall has an axially centered vertically upward extending can dome, wherein the can dome extends away from the can supporting platform, and is bounded immediately adjacent to the can downward facing bottom wall by a vertically extending can dome surface, and the can dome surface has a can dome diameter, the piston outer diameter is greater than the can dome diameter, and is at least twice the coil spring outer diameter, and the can dome diameter is greater than the coil spring outer diameter.

21. Apparatus comprising: a high speed can closing machine including: a rotatable turret, wherein the turret is rotatable about a turret axis, and includes a plurality of angularly disposed can closing stations, wherein each of the can closing stations is positioned at a radially outer periphery of the turret, wherein each can closing station is configured to close a respective can housing a can contained material during less than one turret rotation by joining a can body and a can lid through formation of a continuous fluid tight double seam at an upper circumferential periphery of the respective can body, wherein each can closing station includes an upper chuck, wherein the upper chuck is rotatable about a chuck axis, configured to be held vertically immovable relative to the turret, and configured to engage the can lid positioned in closing relation of an upper opening of the can body, a lower chuck, wherein the lower chuck includes a can supporting platform, wherein the can supporting platform is configured to engage a bottom end of the can body opposed of the upper end, wherein the can supporting platform is rotatable about the chuck axis, and selectively vertically movable relative to the upper chuck, at least two seaming rolls, wherein the seaming rolls are operative to engage an upper annular peripheral flange located adjacent the upper opening of the can body and an annular peripheral portion of the can lid and cause formation of the continuous double seam while the upper chuck is vertically immovable relative to the turret, the can lid is engaged with the upper chuck, the can bottom is engaged with the lower chuck and the can body and the can lid are rotated about the chuck axis, wherein the can closing machine is operative to cause the can bottom end of the can body housing the can contained material to be positioned in axially centered relation on the can supporting platform and to cause the can lid to be positioned in the upper opening, and then cause the can supporting platform to move vertically upward to cause the can lid to engage the upper chuck, wherein the can lid is engaged with the upper chuck with combined vertical momentum of the lower chuck, the can body, the can lid and the can contained material that is not greater than 0.21 Ns.

22. The apparatus according to claim 21 wherein the can closing machine is operative to cause the can lid to engage the upper chuck while moving upward at a velocity within a range of 0.010 to 0.015 m/s.

23. Apparatus comprising: a high speed can closing machine including: a rotatable turret, wherein the turret is rotatable about a turret axis in a first rotational direction, includes a plurality of angularly disposed can closing stations, wherein the can closing stations are positioned at a radially outer periphery of the turret, wherein each can closing station includes a lower chuck, wherein the lower chuck includes a can supporting platform, wherein the can supporting platform is configured to support a bottom end of a can body, wherein the can body houses can contained material, is rotatable about a chuck axis in a second rotational direction opposed of the first rotational direction, is selectively movable vertically relative to the turret, a lower chuck vertical actuator, wherein the vertical actuator is in operative connection with the lower chuck and is operative to vertically position the can supporting platform, an upper chuck, wherein the upper chuck is axially aligned with the chuck axis, is vertically immovable relative to the turret, is rotatable in the second rotational direction and in coordinated relation with the can supporting platform, is configured to engage a can lid, wherein the can lid is positioned in closing relation of a can opening at an upper end of the can body, wherein the upper end is axially opposed of the bottom end, first and second seaming rolls, wherein with the can bottom end engaged with the can supporting platform and the can lid engaged with the upper chuck, the first seaming roll is operative to engage an upper annular peripheral flange on the can body that extends in surrounding relation of the can opening and an annular peripheral portion of the can lid, and responsive at least in part to rotation of the can body and the can lid about the chuck axis, to cause in axial cross section the annular peripheral portion of the can lid to extend around the annular peripheral flange to produce a continuous annular peripheral can double seam, and the second seaming roll is operative to engage the seam after engagement with the first seaming roll, and responsive at least in part to rotation of the can body and can lid about the chuck axis, to cause radial compression of the seam and the seam to be fluid tight, wherein the machine is operative to cause the can body and can lid to be received at the can closing station and cause the can lid and can body to be raised to engage the can lid with the upper chuck, and the can body and can lid to be joined by the fluid tight seam that is operative to close the can opening during less than one turret rotation, wherein the can closing machine is operative to cause the can lid to engage the upper chuck with a vertically upward velocity of not greater than 0.015 m/s.

24. The apparatus according to claim 23 wherein the can closing machine is operative to cause the can lid to engage the upper chuck with combined vertical momentum of the lower chuck, the can body, the can lid and the can contained material that is not greater than 0.21 Ns.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0018] FIG. 1 shows a schematic top view of an exemplary high speed can closing machine.

[0019] FIG. 2 shows examples of cans that are damaged or malformed in the can closing process.

[0020] FIG. 3 is a side view of a can closing station of an exemplary can closing machine.

[0021] FIG. 4 is a side view of an exemplary lower chuck of a can closing station.

[0022] FIG. 5 is a cross-sectional view of the exemplary lower chuck taken along line 5-5 in FIG. 4.

[0023] FIG. 6 is a cross-sectional exploded view of the exemplary lower chuck.

[0024] FIG. 7 is a side view of a portion of an exemplary can closing station including an upper chuck in engagement with a can lid and a pair of seaming rolls.

[0025] FIG. 8 is a side cross-sectional view showing an upper portion of a can body and a can lid in engagement with an upper chuck and a first seaming roll.

[0026] FIG. 9 is a side cross-sectional view showing an upper portion of the can body and the can lid of FIG. 8 in engagement with a second seaming roll.

[0027] FIG. 10 is a side cross sectional view showing an upper portion of the can lid and can body with a fully formed double seam.

[0028] FIG. 11 is a partial view of the can closing station showing the lower chuck in engagement with a lifter cam and a hold down cam and a knockout rod in engagement with a knockout cam.

[0029] FIG. 12 is a partial view of can closing station similar to FIG. 11 showing the components of the knockout rod and the lower chuck in cross section.

[0030] FIG. 13 is an enlarged view showing an upper portion of the lower chuck in engagement with a can body and a knockout pad in engagement with a can lid.

[0031] FIG. 14 is a chart showing an example of the additional force that results from spring deflection in the lower chuck after a can lid is engaged with the upper chuck.

[0032] FIG. 15 shows a bottom perspective view of an alternative mass reduced lower chuck.

[0033] FIG. 16 is a side view of the lower chuck shown in FIG. 15.

[0034] FIG. 17 is a cross-sectional view taken along line 17-17 in FIG. 16.

[0035] FIG. 18 is a view similar to FIG. 17 but also showing an exemplary can in cross section that is in engagement with the can supporting platform of the lower chuck.

DETAILED DESCRIPTION

[0036] Referring now to the drawings and particularly to FIG. 1 there is shown schematically therein a high speed can closing machine generally indicated 10. The exemplary can closing machine includes a turret 12. The turret rotates about a turret axis 14. The turret 12 rotates about the turret axis in a first rotational direction generally indicated T.

[0037] The exemplary turret includes a plurality of can closing stations 16. The can closing stations are located in angularly spaced relation about an outer periphery of the turret 12. The exemplary turret includes 18 can closing stations each of which is configured to join a can body and a can lid in fluid tight relation through the formation of a continuous seam in a manner that is later discussed. In some exemplary arrangements the turret is configured to rotate at a speed of at least 90 rpm and to produce seams on at least 1600 cans per minute. An alternative exemplary arrangement of a can closing machine is configured to operate with the turret 12 rotating at a speed of at least 100 RPM and to produce at least 1800 sealed cans per minute. Some exemplary machines may operate to close at least 2200 cans per minute. In exemplary arrangements the cans are aluminum cans that house contained material such as a beverage or other food for human or other animal consumption. Such cans commonly hold between 8 and 16 ounces of material. Of course it should be understood that these cans are exemplary and in other arrangements other types of cans, can sizes and/or types of can contained materials may be used.

[0038] The exemplary can closing machine operates in connection with a rotatable lid feeding turret 18. The exemplary lid feeding turret 18 includes a plurality of uniformly angularly spaced pockets 20. The exemplary lid feeding turret includes a number of pockets that corresponds to the number of can closing stations on the turret 12. Each pocket 20 is configured to hold a can lid 22 which is shown in phantom. Lid feeding turret 18 rotates in a second rotational direction indicated L which is opposed of the first rotational direction in the exemplary arrangement. During operation of the machine, can lids are fed into the pockets such that each pocket holds a can lid as the lid feeding turret moves the lid into a make up position 24 in which the lid is placed in closing relation of an upper opening of a respective can body 26.

[0039] Can bodies such as can body 28 shown, are delivered to the turret 12 by a can feed conveyor 30. In the exemplary arrangement cans are moved through engagement with movable can engaging projections 32. In exemplary arrangements the cans that are moved by the can feed conveyor 30 into engagement with the turret 12 are filled with a beverage or other can contained material that is to be sealed within the can body, but each can body has a respective upper opening that is configured to be closed by a lid that is delivered in the makeup position 24.

[0040] The exemplary can closing machine operates to receive the can body including the can contained material and the lid at the can closing station corresponding to the makeup position 24 and moves the can and lid in a manner like that later discussed in detail to produce a continuous fluid tight double seam that joins the can body and lid in sealed relation. The seams are formed in less than one rotation of the turret 12. The sealed cans are then engaged with a take away turret 34. Cans are guided into a station at the periphery of the take away turret 34 at a position 36. The cans as represented by a can 38, are then moved with the take away turret which rotates in the second rotational direction, as indicated by the arrow O, in guided relation with a curved guide 40 to an output position 42. Of course it should be understood that this configuration is exemplary and in other arrangements other devices and configurations may be used.

[0041] As can be appreciated the can closing machine 10 operates to reliably and accurately join lids and can bodies without causing damage to the can body or the seam. The speed and force of the components which operate to form the seams which join the can bodies and lids can result in significant forces being applied both vertically, tangentially and rotationally to the can bodies. FIG. 2 shows examples of damaged cans which may have malformed seams that can result from excessive or improperly applied forces, improper set up or other factors during operation of the can closing machine. The effects of the type shown in FIG. 2 can particularly arise when a can closing machine that has been set up for handling standard aluminum cans with can bodies with a column strength (meaning vertical column strength without sustaining permanent deformation such as buckling, of the vertically extending annular outer can side wall) of approximately 675 N (150 pounds), is operated to close aluminum can bodies which have been gauge reduced and include a thinner can side wall such that the can bodies have a column strength of approximately 550 N (120 pounds). As used herein the reference to an approximate column strength of a can body shall mean the column strength indicated, plus or minus 10%. As can be appreciated the production of scrap material results in losses that exceed any benefit that is achieved by reducing the amount of aluminum included in the can bodies.

[0042] The exemplary can closing machine is configured to operate reliably in closing aluminum cans with standard can bodies that have a higher column strength as well as cans with can bodies that include less material and which have a lower column strength.

[0043] In the operation of the exemplary arrangement each can closing station 16 includes a lower chuck 44. The lower chuck includes a can supporting platform 46. The can supporting platform 46 is configured for engaging a bottom end 48 of a can body 50 which is similar to can body 26, in axially centered relation. The can supporting platform 46 is rotatable about a chuck axis 52. The can supporting platform 46 is also selectively movable vertically relative to the turret 12.

[0044] Each can closing station 16 further includes an upper chuck 54. The upper chuck 54 is configured to be in a fixed vertical position and rotates in coordinated relation with the can supporting platform 46. The upper chuck rotates in the same rotational direction and at the same speed as the can supporting platform. In exemplary arrangements the can supporting platform and the upper chuck each rotate in an opposed rotational direction from the rotational direction of the turret 12. Further in an exemplary arrangement when the turret rotates at about 100 RPM about the turret axis 14, the can supporting platform and the upper chuck rotate about the chuck axis 52 at about 2000 RPM. Of course this configuration is exemplary and in other arrangements other approaches and parameters may be used.

[0045] The exemplary upper chuck is configured to engage a can lid such as can lid 56 which is similar to can lid 22. As previously discussed the can lid is configured to close an upper opening 58 of the can body 50. As shown in FIG. 7 in the exemplary arrangement an upper annular peripheral flange 60 extends radially outwardly and in continuous surrounding relation of the can opening 58. The can lid 56 includes a continuous annular peripheral portion 62 that in the undeformed position extends above and in radially outward overlying relation of the flange 60.

[0046] The exemplary can closing station 16 further includes a knockout pad 64. As later discussed in detail, the knockout pad 64 is axially centered with the chuck axis and operates to apply a downward force on the upper side of the can lid 56 prior to lid engagement with the upper chuck. The knockout pad 64 applies a force which opposes the upward movement of the can lid and can body until the can lid is engaged with the upper chuck 54. The knockout pad 64 also rotates in coordinated relation with the upper chuck and the can supporting platform to help maintain the lid and the can body in relatively fixed positions prior to the seam being produced.

[0047] Each can closing station further includes at least one seaming roll. In exemplary arrangements each can closing station includes a first seaming roll 66 and a second seaming roll 68. The can closing machine operates the seaming rolls in the manner described in the incorporated disclosures to cause a continuous fluid tight double seam to be produced through deformation of the annular peripheral portion of the can lid 62 and the upper annular peripheral flange 60 of the can body.

[0048] In the exemplary arrangement the first seaming roll 66 is selectively moved to operatively engage the peripheral portion of the lid 62 and the peripheral flange 60 of the can body, so that responsive to rotation of the can body and can lid about the chuck axis, an initial seam configuration is formed. In the exemplary arrangement the first seaming roll 66 is operative to cause in axial cross section, the annular peripheral portion of the lid to extend around the annular peripheral flange of the can body. An example of an initial seam configuration which is caused to be formed by the first seaming roll 66 is shown in FIG. 8.

[0049] In the exemplary arrangement after the initial seam configuration is formed through operation of the first seaming roll 60, the can seam is then selectively operatively engaged by the second seaming roll 68. As represented in FIG. 9 the second seaming roll acts to cause the continuous double seam to be further formed and radially inwardly compressed as the can body and can lid are rotated about the chuck axis. The action of the second seaming roll 60 along with a layer of sealing compound that is applied on the peripheral portion of the lid and/or peripheral flange of the can body prior to engagement with the seaming rolls, produces a continuous fluid tight double seam 70, an exemplary final configuration of which is shown in FIG. 10. As represented in axial cross section in FIG. 10, in the fully formed condition of the continuous seam 70, three layers of the lid material are pressed into abutting engagement with two layers of the can body material to produce the final seam. Of course it should be understood that this approach is exemplary and other arrangements other approaches may be used.

[0050] An exemplary lower chuck 44 is shown in greater detail in FIGS. 4-6. The exemplary lower chuck is configured to have a mass that is substantially less than some other lower chucks that have been used in can closing machines. The reduced mass configuration provides significant advantages in terms of enabling more precise control of vertical displacement, velocity and momentum of the can supporting platform and the can supported thereon. These capabilities of the exemplary arrangement reduce the risk of damage particularly to weight reduced aluminum cans during the can closing process.

[0051] In the exemplary arrangement the lower chuck includes a central chuck gear 72. The chuck gear is in centered relation with the chuck axis 52. In the exemplary arrangement the chuck gear is configured to rotate in response to engagement with an annular stationary gear as the turret and the lower chuck rotate about the turret axis. Of course this approach to providing rotation of the lower chuck is exemplary and in other arrangements other rotational drives may be used.

[0052] The chuck gear 72 is in operative fixed connection with a chuck shaft 74. In some exemplary arrangements the chuck shaft may be integrally formed with the chuck gear. The chuck shaft 74 includes an upper portion 76 and a lower portion 78. The chuck shaft upper portion includes an axially centered recess 80. A coil type compression spring 82 extends in aligned relation with the chuck axis and a lower end of the spring is in nested relation within the recess 80.

[0053] A piston 84 which serves as a vertical guide includes an axially centered cylindrical cavity 86. The upper portion of the chuck shaft 76 extends in the cavity 86 such that an inner annular wall 87 of the cavity 86 of the piston extends in contacting annular surrounding relation of the upper portion of the chuck shaft. The exemplary piston 84 includes a pair of opposed axially elongated slots 88 at a lower end. A respective pin 90 extends in a respective axially elongated slot and is in threaded engagement with the upper portion of the chuck shaft. As a result in the exemplary arrangement the piston is in fixed rotational connection with the upper portion of the chuck shaft and is axially movable relative to the upper portion of the chuck shaft.

[0054] The exemplary piston 84 includes an axially extending threaded opening 92 that extends vertically above the cavity 86. The threaded opening 92 is configured to receive therein a spring adjusting screw 94. The exemplary spring adjusting screw 94 is selectively axially positionable in the threaded opening 92 through rotation of the screw. The inner end of the spring adjusting screw 94 is in engaged relation with a centering washer 96. The exemplary centering washer 96 is configured to extend within the central portion of the coils of compression spring 82 and provide a uniform horizontal surface that engages the inner face of the spring adjusting screw 94. The exemplary spring adjusting screw is configured to be selectively axially positioned to provide a preload force on the compression spring. The set preload force operates to require that the axially downward force acting on the compression spring must exceed the preload before the compression spring will begin to deform. Of course it should be understood that this approach is exemplary and in other arrangements other approaches may be used.

[0055] The exemplary piston 84 is axially centered in an upper annular sleeve 98. Sleeve 98 is in fixed operative connection with the turret 12. In the exemplary arrangement the sleeve 98 includes an annular outward projection which is operative to vertically position the sleeve in an opening in the turret. A gasket 100 and an o-ring 102 are operative to cause the upper sleeve 98 to be in sealed connection with the opening.

[0056] In the exemplary arrangement the upper sleeve includes an annular bushing 104 that is positioned in radially intermediate relation between an outer surface of the piston 84 and an upper sleeve inner surface. The piston is rotationally and axially movable relative to the upper sleeve while in contacting relation with the annular bushing. A cap 106 extends in overlying relation of the top of the upper sleeve 98. A seal 108 extends below the cap 106 and radially intermediate of the piston and the upper sleeve. The exemplary seal 108 helps to prevent loss of lubricant that is delivered to the area of the bushing radially intermediate of the piston and the sleeve in the manner that is later discussed.

[0057] The exemplary piston 84 includes an axially centered upward extending annular projection 110. The projection 110 extends above and in surrounding relation of the threaded opening 92. A seal 112 extends radially and in surrounding relation of the projection 110. The exemplary projection 110 extends in an opening in a shield 114. The exemplary shield 114 extends above and in outwardly overlying relation of the top of the piston 84 and the vertically extending sides of the upper sleeve 98. At least one annular shim 116 extends in underlying relation of the shield 114 and in surrounding relation of the central projection 110. The can supporting platform 46 extends in overlying relation of the shield 114 and is held in releasably attached connection therewith by releasable fasteners 118. In exemplary arrangements the one or more shims 116 are usable to precisely set the vertical position of the upper surface of the can engaging platform.

[0058] The exemplary configuration of the piston 84 and upper sleeve 98 enable the piston to be vertically and rotationally movable while in contacting relation with the upper sleeve. This enables the can supporting platform 46 to be both vertically and rotationally movable relative to the sleeve. The exemplary construction further enables the piston while in contacting relation with the upper portion of the chuck shaft to be axially movable relative to the chuck shaft against the biasing force of the compression spring 82. This exemplary configuration enables the piston to serve as a guide that provides for precise positioning and movement in the rotational and vertical directions of the can supporting platform, while having significantly less mass than structures used in some prior can closing machines.

[0059] In the exemplary arrangement the configuration of the piston 84 and the coils of the compression spring 82 reduce the risk of vibration and chatter caused by the axial and rotational movement of the piston relative to the upper sleeve 98 and the rotational movement of the lower chuck with the coils of the compression spring therein. The exemplary piston 84 has a radially outer annular piston surface 89 that is relatively rotatable and axially movable while in contacting engagement, with the bushing of the upper sleeve 98. The maintenance of contacting engagement of the piston with both the upper portion of the shaft 76 and the upper sleeve 98 as the piston undergoes rotational and axial movement avoids radial play and minimizes the risk of vibration and chatter despite high-speed rotation and the application of axial and radial forces. Further in the exemplary arrangement the diameter of the outer piston surface 89 being greater than the outer diameter of the coils of the expression spring, and in the exemplary arrangement being at least twice the outer diameter of the coils of the compression spring, helps to further reduce the risk of force imbalance that may cause vibration resulting in can damage and malformed can seams.

[0060] Further the exemplary arrangement is configured to handle cans the bottom ends of which commonly include a radially inward tapered lower shoulder that extends to an annular downward facing bottom wall that surrounds a vertically upward extending central can dome. Such can bottom ends have an annular vertically extending can dome surface that radially outwardly bounds the can dome and radially inwardly bounds the downward facing can bottom wall. While the can is axially centered on the can supporting platform of the lower chuck, the annular vertically extending can dome surface is radially inboard of the annular outer piston surface 89. In this arrangement the piston outer diameter is greater than the can dome diameter of the vertically extending can dome surface. Having the piston diameter associated with the annular outer piston surface greater than the can dome diameter, and having the can dome diameter greater than the coil spring outer diameter, maintains proper component alignment and balance during the lower chuck operation which achieves more stable, vibration free and chatter free operation of the lower chuck during can closing and seaming operations.

[0061] The exemplary lower chuck further includes a slider 120. The exemplary slider 120 includes an axially centered cylindrical cavity 122. The lower portion 178 of the chuck shaft extends in the slider cavity 122. At least one bearing 124 is positioned in the slider cavity and operatively extends radially intermediate of the chuck shaft and the slider. In exemplary arrangements the at least one bearing 124 includes a plurality of bearings configured to prevent relative axial and radial movement between the slider and the chuck shaft. Of course this approach is exemplary and in other arrangements other bearing approaches may be used.

[0062] The exemplary slider 120 includes a pair of disposed downward extending legs 126. Each of the legs 126 includes an opening that is configured to receive a shaft 128 therein. A cam roller 130 is rotatable on the shaft 128 in intermediate relation of the legs 126. As a result the cam roller is mounted in journalled relation on the slider 120. In the exemplary arrangement a releasable retainer 132 is used to hold the shaft 128 and the cam roller 130 in position. However it should be understood that in this exemplary arrangement the retainer 132 may be released so that the cam roller is removable from engagement with the slider.

[0063] The exemplary slider includes an axially centered access opening 134 that is positioned above the cam roller 130. A removable access cover 136 is configured to close the access opening in fluidly sealed relation. With the cam roller and the access cover 136 removed, a removable retainer 138 is accessible through the access opening. The retainer 138 is configured to engage the lower portion 78 of the chuck shaft 74 and hold the chuck shaft in a fixed axial position relative to the slider, while enabling the shaft to rotate relative to the slider and in the slider cavity 122. Of course it should be understood that this arrangement is exemplary and in other arrangements other approaches for holding the shaft in relatively rotatable engagement with the slider may be used.

[0064] A lower annular sleeve 140 extends in surrounding relation of the slider 120. The lower sleeve 140 is in fixed operative connection with the turret 12. The lower sleeve 140 is configured to enable the slider to move while in contacting relation with the lower sleeve vertically along the chuck axis 52 within the lower sleeve. This arrangement further provides radially playless relative vertical movement of the lower sleeve and the slider.

[0065] In the exemplary arrangement a further cam roller 142 is mounted in journalled relation with the shaft 128. In the exemplary arrangement the cam roller 130 and the further cam roller 142 of the lower chuck are operatively engaged with a lower chuck vertical actuator. The exemplary vertical actuator is operative to cause selective vertical movement and positioning of the can supporting platform 46. This is accomplished in the exemplary arrangement by engagement of the cam roller 130 with the stationary lifting can 144 of the machine. The further cam roller 142 is in operative engagement with a stationary hold down cam 146 of the machine. In the exemplary arrangement lower chuck vertical actuator includes the lifting cam and the hold down cam which are each respective annular stationary cams which extend at each can closing station and with which the respective cam roller and hold down roller of the upper chuck may remain engaged throughout rotation of the turret 12.

[0066] However it should be understood that this lower chuck vertical actuator configuration is exemplary and in other arrangements other types of vertical actuators may be used. These may include for example hydraulic or electrical motors or other drives that selectively move gears, pistons, screws or other components to provide the desired vertical positions, velocities, acceleration and other properties to components of the lower chuck and the can supporting platform 46.

[0067] The exemplary lower chuck further includes components which provide the delivery of lubricant to the areas where lubrication is needed. In the exemplary arrangement an impeller 148 extends in the slider cavity 142. The exemplary impeller is in fixed rotational connection with the lower portion of the shaft through a key 150. The exemplary impeller includes an external helical groove 152 configured to move lubricant therein in a downward direction with rotation of the chuck shaft. The impeller and the groove thereof extend within a pump ring 154. In the exemplary arrangement a pair of annular wave springs 152 extend axially intermediate of the pump ring 154 and the bearings 124. A snap ring 158 is positioned axially above the pump ring and is operative to hold the pump ring in position.

[0068] In the exemplary arrangement the chuck shaft 74 includes a shaft lubricant passage 160 that extends axially therein. The lubricant passage is in fluid communication through a central opening in the retainer 138 with the bottom portion of the slider cavity 122. The lubricant passage is also in fluid communication with the cavity 86 in the piston 84. Radially extending piston lubricant passages 162 extend outwardly from the cavity 86 and are configured to deliver lubricant to the area of the bushing 104 and radially intermediate of the outer surface of the piston and the inner surface of the upper annular sleeve.

[0069] During operation of the can closing machine, rotation of the chuck shaft is operative to cause lubricant in the area above the slider cavity 122 to be moved downward by rotation of the impeller 148. Lubricant passes through the bearings 124 and to the bottom of the slider cavity. The lubricant then passes upwardly through the opening in the retainer 138 and the lubricant passage 162 to the area of the upper shaft recess 80 and the piston cavity 86. Lubricant then moves radially outwardly through the piston lubricant passages 162 to provide lubrication and cooling in the area of contact between the piston, the bushing and the upper sleeve. Lubricant is then enabled to pass downward from the area of the bushing as shown into the area of the gear 72. Also in the exemplary arrangement lubricant passages are provided in the lower chuck to deliver lubricant into the shaft 128 and to the areas underlying the cam roller 130 and the further cam roller 142. Thus the exemplary lower chuck assures the delivery of lubricant to the relatively moving areas to maintain reliable high-speed operation. Of course it should be understood that this approach is exemplary and other arrangements other approaches may be used.

[0070] As shown in FIGS. 11-13 the exemplary knockout pad 64 is in operative connection with a rotating axially extending knockout rod 164. As shown in FIG. 13 the knockout pad is configured to engage the central portion of the can lid 22 but is sufficiently radially inwardly disposed from the area of the can lid that is engaged by the upper chuck 54.

[0071] The exemplary knockout rod 164 is configured to be vertically movable responsive to a knockout cam roller 166. The knockout cam roller 166 moves the knockout pad responsive to engagement with a knockout cam 168. In the exemplary arrangement the knockout cam is a stationary annular cam with which the knockout cam roller remains engaged throughout rotation of the turret 12.

[0072] The exemplary knockout rod 164 is biased vertically downward by a knockout spring 170. In the exemplary arrangement the knockout spring is subject to a preload which prevents the knockout rod and the knockout pad from moving upward along the chuck axis responsive to the upward force applied to the knockout pad by the can lid, until the preload is exceeded.

[0073] In the operation of the exemplary can closing station 16 the can body 50 and the can lid 56 are placed in engagement at the makeup position 24. In this position the lid closes the upper opening of the can body and the lid is disposed in axially centered relation vertically below the upper chuck 54. Rotation of the turret 12 causes the lower chuck vertical actuator to move the can supporting platform 46 upward while the knockout cam causes the knockout pad 64 to move into engagement with the can lid. In the exemplary arrangement the knockout spring 170 is operative to apply a downward force opposing the upward movement of the can lid and can body while the lid and body are rotating in supported engagement with the can supporting platform 46. To prevent can wobble the exemplary knockout pad applies a vertically downward force as the can lid is moving toward the upper chuck. In some arrangements the downward force is in the range of 33 pounds to 70 pounds (22 N to 312 N). In other arrangements where can wobble is a greater problem the pad applies a vertically downward force on the lid in the range of from about 50 pounds to 70 pounds (222 N to 312 N) as the can lid is moving upward toward the upper chuck. In an exemplary arrangement the can body moves vertically about 23 mm (0.906 in.) from the makeup position to the point of engagement of the lid with the upper chuck. This knockout pad force is applied while the turret rotates through at least 5 and in some arrangements 15, prior to engagement of the lid and upper chuck.

[0074] In the exemplary arrangement this knockout pad applied downward directed force on the can lid and can body may be substantially greater than is utilized in some other can closing machines. The force may be more than double the knockout pad force in some machines that handle current standard weight cans. This additional downward force which is directed axially toward the can supporting platform by the knockout pad, causes the can body to move and rotate in centered relation with the rotating can supporting platform. In the event that the bottom end of the can body becomes radially displaced away from the centered position on the rotating can supporting platform, this downward force causes a radial force to be produced at the can bottom which moves the can bottom back into centered relation. Applying an increased level of vertically downward force, particularly with weight reduced cans, is operative to cause the can body to remain centered and to prevent can wobble during upward movement of the can toward the upper chuck.

[0075] In operation of the exemplary can closing station 16 the vertically upward position, velocity and momentum of the lower chuck, the can body and its contents, and the can lid are controlled so as to reduce the risk of damage to the can or defects in the seam that is produced. In the exemplary arrangement the configuration of the lower chuck provides that the combined vertical momentum of the lower chuck, the can body, can lid and the can contained material when the can lid engages the upper chuck, is not greater than 0.21 Ns. In some exemplary arrangements this momentum is less than one tenth of the momentum at the time of lid and upper chuck engagement in other machines. This is achieved in the exemplary arrangements by the relatively low mass of the lower chuck and the carefully controlled upward velocity of the can supporting platform at the time of engagement between the lid and the upper chuck. In some exemplary arrangements the relative vertical velocity at lid and upper chuck engagement is not greater than 0.015 m/s and in the range of 0.010 to 0.015 m/s. In some exemplary arrangements the vertical velocity at the time of engagement of the lid and the upper chuck is about 0.0128 m/s. Operating the can closing machine in accordance with these parameters has been shown to enable the machine to operate satisfactorily with weight reduced cans that have column strength of about 550 N, as well as cans which have a greater column strength such as cans with a column strength of 675 N.

[0076] Further in exemplary arrangements the risk of damage to lighter weight cans is reduced by causing the force applied by the compression spring and the lower chuck to increase at a uniform rate after the lid is engaged with the upper chuck. In an exemplary arrangement the lower chuck vertical actuator operates to cause the lower end of the compression spring 82 to move upward at a constant velocity over a distance of between 0.013 to 0.017 cm after lid and upper chuck engagement. The upward movement at a constant velocity causes the application of a uniformly linearly increasing vertical force after upper chuck engagement and while the can is rotating about the chuck axis. This reduces the risk of damage to weight reduced cans with a lower column strength.

[0077] Further in exemplary arrangements the coil compression spring of the lower chuck is set to a preload in a range of from 355 N to 445 N. Thus in the exemplary configuration the additional axial force that is applied to the can as a result of the movement of the bottom end of the spring upward at a constant velocity after engagement of the lid with the upper chuck, is less than 36 N. This additional applied force is represented in the chart in FIG. 14 by the lower line which corresponds to a lower chuck configuration in which the compression spring has a spring rate of 314 pounds per inch (549.8 N per centimeter) and in which the lower end of the compression spring moves upward at a constant velocity which corresponds to 0.00084 inches (0.00213 cm) during each degree of rotation of the turret 12. The upper line in FIG. 14 corresponds to an exemplary existing machine. Of course it should be understood that the lower line in FIG. 14 is but one exemplary configuration that is utilized in closing cans in an exemplary machine utilizing the new approaches described herein.

[0078] It should be understood that while in the exemplary arrangement controlled increased force is applied through deformation of a compression spring, in other exemplary arrangements other force controlling mechanisms may be used. Such mechanisms may operate to provide controlled force using other types of springs or controlled levels of fluid pressure, for example.

[0079] FIGS. 15-18 show an alternative mass reduced lower chuck 172. Chuck 172 is generally similar to lower chuck 44 previously described, except as otherwise indicated. Chuck 172 includes a chuck shaft 174. Similar to the previously described arrangement the chuck shaft 174 extends along a central axis 176 which extends vertically in the operative position. The chuck shaft includes a chuck shaft upper portion and a chuck shaft lower portion 180. The chuck shaft also includes a central chuck gear 182.

[0080] Similar to the previously described lower chuck, the chuck shaft upper portion 178 includes a recess 184. A coil type compression spring 186 has its lower end positioned in nested relation within the recess 184. The coil spring has a spring outer diameter that relatively closely corresponds to the diameter of the recess 184 but is somewhat smaller. An upper end of the coil spring extends upward beyond the recess.

[0081] A piston 188 which serves as a guide, extends in surrounding relation of the upper shaft portion. The piston 188 includes an inner wall 190 that is movable both axially and rotationally in contacting engagement with the annular outer wall of the chuck shaft upper portion 178. A lower end of the piston 188 includes a pair of radially extending axially elongated slots 192. A pair of radially inward directed screws or pins 194 extend in the slots 192 and are engaged with the chuck shaft 174. As a result the piston 188 is in rotationally fixed operative connection with the chuck shaft but is axially movable relative thereto.

[0082] The exemplary piston includes a cavity 196 in which the upper end of the compression spring 186 extends. A centering washer 198 is in engagement with the top of the spring. The exemplary centering washer 198 includes a generally planar circular upper surface and a central projecting portion that extends from the lower surface and into the interior of the upper coils of the spring 186.

[0083] The piston 188 further includes a bore 200 that extends axially upward from the cavity 196. The bore 200 includes an internally threaded portion 202. A spring adjusting screw 204 is in engagement with the threaded portion. The spring adjusting screw includes an upper portion 205 which is engageable with a suitable tool to enable rotation of the adjusting screw 204. The spring adjusting screw 204 is in operative connection with the compression spring through the centering washer. As a result the spring biases the piston upward. The adjusting screw is selectively axially positionable in the bore to enable selectively setting a preload force on the piston. In a manner similar to that previously discussed, the preload force assures that the piston does not vertically move relative to the chuck shaft until the axially acting downward force exceeds the preload force.

[0084] An upper sleeve 206 extends in annular surrounding relation of the piston 188. Similar to the upper sleeve of the previously described arrangement the upper sleeve 206 is in operatively fixed connection with the turret. The upper sleeve 206 includes an outward extending flange 208. A gasket 210 that extends below the flange and an annular resilient o-ring 212 are operative to maintain the upper flange in fluid tight connection with the turret.

[0085] The exemplary upper sleeve 206 includes an annular bushing 214. Bushing 214 includes an annular inner surface 216 of the upper sleeve. The annular inner surface 216 is in axially movable rotatable contacting engagement with an annular outer surface 218 of the piston 188. Similar to the previously described arrangement, these features provide for radially playless contacting engagement between the upper portion of the chuck shaft, the piston and the upper sleeve. This configuration avoids vibration and chatter which might otherwise result from applied axial and radial forces.

[0086] The lower chuck 122 includes a can supporting platform 220. Can supporting platform 220 includes a circular upward facing can supporting surface. The exemplary can supporting platform 220 includes an annular vertically extending outer surface 222. The exemplary outer surface includes four equally angularly spaced openings in which holding fasteners 224 inwardly extend. In the exemplary arrangement the openings are internally threaded such that the fasteners releasably engage in respective recesses 226 that extend in the upper portion of the piston 188. As a result the can supporting surface is in fixed operative connection with the piston. A shield 225 extends below the can supporting platform and in outward overlying relation of the upper portion of upper sleeve 206.

[0087] This exemplary arrangement enables removal of the can supporting platform 220 and disengagement from the piston by loosening the holding fasteners 224. Removal of the can supporting platform enables access to the upper portion 205 of the spring adjusting screw 204. As a result the preload on the spring 186 may be readily adjusted due to the ability to remove the can supporting platform 220 with access only from the side. Of course this approach is exemplary and in other arrangements other approaches for releasably engaging the can supporting platform and the piston may be used.

[0088] The chuck shaft lower portion 180 extends in axially centered relation in a slider 228. Slider 228 includes a slider cavity 230. The slider cavity is bounded inwardly by an annular inner wall 232. Bearings 234 extend radially between the annular inner wall 232 and the outer surface of the chuck shaft lower portion 180. In the exemplary arrangement the bearings 234 are held in engagement with the slider axially between a retainer 236, which in the exemplary arrangement comprises a snap ring, and an inward extending annular ledge 238 that extends at the bottom of the annular inner wall 232.

[0089] Further in the exemplary arrangement a spacer 240 extends axially upward from engagement with the inner race of the uppermost bearing 234 toward the radially extending bottom surface of the chuck gear 182. One or more shims 242 are positioned axially between the upper annular surface of the spacer 240 and the radially extending lower surface of the gear 182. The shims 242 enable accurately setting, adjusting and maintaining the desired axial distance between the chuck gear 182 and the slider 228. Of course it should be understood that this approach to adjusting and maintaining the position of the slider relative to the chuck shaft is exemplary and in other arrangements other approaches may be used.

[0090] The exemplary slider further includes a pair of downward extending horizontally disposed legs 244. The legs bound an access opening 246. A retaining fastener 248 is positioned in the access opening 246. The retaining fastener includes an upper threaded portion that is engageable in a threaded opening in the chuck shaft lower portion 180. A washer or spacer 250 extends in surrounding relation at the lower end of the threaded portion of the retaining fastener and in engagement with the bottom end of the chuck shaft.

[0091] The legs 244 include horizontal access openings in which a shaft 252 extends. Similar to the prior arrangement, a cam roller 254 is mounted on the shaft and is rotatable in journalled relation with the slider. The cam roller 254 is in operative connection with a stationary lifter cam of the machine and moves in engagement with the lifter cam responsive to rotation of the turret.

[0092] A further cam roller 256 is in rotatable engagement with the shaft 252. Similar to the previously described further cam roller, cam roller 256 is in operative connection with a stationary hold down cam of the machine. In the exemplary arrangement the further cam roller 256 is held in axial position on the shaft 252 by a washer 258 and a releasable retaining ring 260. As can be appreciated removal of the shaft 252 enables accessing the access opening 246 so that the retaining fastener 248 may be removed to facilitate disassembly of the exemplary slider. Of course it should be understood that this construction is exemplary and in other arrangements other slider configurations may be used.

[0093] A lower annular sleeve 262 extends in surrounding relation of the slider 220. An outward extending annular flange on the lower sleeve is operative to engage and hold the lower annular sleeve in relatively fixed axial position relative to the turret. The lower annular sleeve includes an inner annular surface 268. An annular outer surface of the slider 220 is axially movable in contacting engagement with the inner annular surface 268.

[0094] The exemplary lower sleeve includes a downward extending skirt 270. Skirt 270 includes a slot 272. A guide 274 which is in fixed connection with the slider through at least one fastener 278 is vertically movable in guided relation in the slot 272. In the exemplary arrangement the interengaging slot 272 and guide 270 assure that the slider is only movable vertically and that the shaft and cam rollers thereon are properly oriented relative to the stationary cams of the machine. Of course it should be understood that this approach is exemplary and in other arrangements other structures for guiding and orienting the slider and the cam rollers may be used.

[0095] In this exemplary mass reduced lower chuck some of the features of the previously described mechanism are not included which reduces the mass of the lower chuck. For example the impeller and other structures that are used for pumping lubricant are not included in this lower chuck configuration. Rather the exemplary arrangement provides a lubricant inlet 278 in the upper sleeve 206. Lubricant from the inlet 278 passes into engagement with the piston 188 and is moved upward in small grooves in the piston outer surface 218 in response to the rotational and axial movement of the piston relative to the upper sleeve. The lubricant passes upward on the outside of the piston to a chamber below a seal 280. From the chamber below seal 280 the lubricant passes through a passage 282 in the upper sleeve. Lubricant exiting the passage 282 passes downward to the chuck gear 182 and further downward to the slider and the bearings. An additional lubricant inlet 284 extends in the lower annular sleeve 262. The lubricant received through the lubricant inlet passes through internal passages and lubricates the cam rollers and other components. Of course it should be understood that this lubrication approach is exemplary and in other arrangements other approaches may be used.

[0096] FIG. 18 shows the exemplary lower chuck 172 in supporting relation with a can 286. The exemplary can is shown in cross section and in axially centered engagement with the can supporting platform 220. Lower chuck 172 includes similar component configurations to the previously discussed lower chuck 44, which minimizes the risk of vibration and chatter of the lower chuck despite the application of axial and radial forces.

[0097] Can 286 includes the annular vertically extending outer can wall 288. The can wall 288 terminates downwardly at a radially inward tapered lower shoulder 290. Shoulder 290 at the bottom end of the can terminates at an annular downward facing bottom wall 292 that is in abutting engagement with the upper surface of the can supporting platform.

[0098] The bottom end of the can includes an upward extending can dome 294. The can dome extends upwardly away from the upper surface of the can supporting platform. The can dome 294 is radially outwardly bounded by an annular vertically extending can dome surface 296. The annular vertically extending can dome surface has a can dome diameter D as shown in FIG. 18.

[0099] The outer diameter of the coils of the compression spring 186 have a spring diameter S. As further shown in FIG. 18, the piston outer surface 218 of the piston 188 has a diameter P which is greater than the can dome diameter. Similar to the previously described lower chuck, the diameter the piston outer surface in this exemplary arrangement is more than twice the spring outer diameter S. This exemplary arrangement in which the diameter the piston outer surface P is greater than the can dome diameter D, and the can dome is greater than the spring diameter S, provides for generally vibration and chatter free operation of the lower chuck. As a result these features in addition to the reduced mass of the lower chuck, helps to enable reliably closing cans that are weight reduced and that have lower column strength.

[0100] The exemplary can closing machine described herein operates to close cans that have a weight reduced configuration and a lower column strength with a reduced risk of damage or flaws in the cans and seams that are produced. The exemplary arrangements enable successfully closing both lighter weight cans and cans of a standard gauge and higher column strength configuration on the same machine at high production rates.

[0101] Thus the exemplary arrangements achieve improved operation, eliminate difficulties encountered in the use of prior apparatus and systems, and attain the useful results described herein.

[0102] In the foregoing description certain terms have been used for brevity, clarity and understanding. However, no unnecessary limitations are to be implied therefrom because such terms are used for descriptive purposes and are intended to be broadly construed. Moreover the descriptions and illustrations herein are by way of examples in the new and useful features and relationships are not limited to the exact features and relationships that have been shown and described.

[0103] Having described features, discoveries and principles of the exemplary arrangements, the manner in which they are constructed and operated, and the advantages and useful results attained, the new and useful features, devices, elements, arrangements, parts, combinations, systems, equipment, operations, methods, processes and relationships are set forth in the appended claims.