Accumulating conveyor

Abstract

An accumulating conveyor includes upper and lower runs which form upper and lower tracks, reverse sections connecting the upper and lower runs, and a deflecting element connected to a first motor. Endless tension elements engaged with a deflecting element circulate a pallet in the upper and lower runs. A stop element is on the underside of the pallet, and a stopping element is arranged between the upper and lower runs and driven by a second motor. The stopping element has a locking position with the stop element for stopping the pallet and a release position with the stop element for conveying the pallet. The stopping element is guided in sections around the stop element on a curved path during movement from the locking position to the release position to release the pallet for further conveying.

Claims

1. An accumulating conveyor for conveying piece goods on pallets, the accumulating conveyor comprising: an upper run that forms an upper conveyor track; a lower run that forms a lower conveyor track; a reverse section that connects said upper run and said lower run; a deflecting element in said reverse section and connected to a first motor; an endless tension element in driving engagement with said deflecting element; a pallet entrained by said endless tension element to circulate therewith; a stop element on an underside of said pallet; a stopping device between said upper run and said lower run and driven by a second motor; wherein said stopping device has a locking position in a travel path of said stop element for stopping said pallet on said upper conveyor track, and said stopping device has a release position for releasing said stop element and thus said pallet for further conveying along said upper conveyor track; wherein said stopping device comprises a plurality of stopping elements; and wherein each of said stopping elements moves around said stop element on a curved path between said locking position and said release position and said stopping elements bear against at least two spaced-apart places in a circumference of said stop element when said stopping device is in said locking position.

2. The accumulating conveyor as in claim 1, wherein said second motor rotates said stopping device about a rotation axis between said locking position and said release position.

3. The accumulating conveyor as in claim 2, wherein said second motor rotates said stopping device on an elliptical path about said rotation axis.

4. The accumulating conveyor as in claim 2, wherein said rotation axis extends in the horizontal or vertical direction.

5. The accumulating conveyor according to claim 2, wherein said rotation axis extends through said stop element when said stopping device is in said locking position.

6. The accumulating conveyor as in claim 5, wherein said stop element has a longitudinal axis and said rotation axis coincides with said longitudinal axis when said stopping device is in said locking position.

7. The accumulating conveyor as in claim 1, wherein said stopping device comprises a plurality of elongated bushings arranged transverse to said travel path when said stopping device is in said locking position.

8. The accumulating conveyor as in claim 1, wherein said stopping device comprises a plurality of rotatably mounted round bushings which roll off said stop element when said stopping device moves from said locking position to said release position.

9. The accumulating conveyor as in claim 1, wherein said stopping device is plate-shaped and envelops said stop element in sections when said stopping device is in said locking position.

10. The accumulating conveyor as in claim 1, further comprising a platform rotatably driven by said motor, and said stopping device is arranged on and projects from said platform.

11. The accumulating conveyor as in claim 1, wherein said stop element is cylindrical.

12. The accumulating conveyor as in claim 1, wherein said stop element projects from said underside of said pallet at a 90° angle to said pallet.

13. The accumulating conveyor as in claim 1, wherein said stop element projects parallel to said underside of the pallet.

14. The accumulating conveyor as in claim 1, wherein said second motor is an electric motor, a pneumatic motor, or a hydraulic motor.

15. The accumulating conveyor as in claim 1, comprising a plurality of stopping devices spaced apart in a transverse transport direction.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) A full and enabling disclosure of the present invention, including the best mode thereof to one skilled in the art, is set forth more particularly in the remainder of the specification, including reference to the accompanying figures, in which:

(2) FIG. 1 shows a perspective partial view of an accumulating conveyor with a reversing section;

(3) FIG. 2 shows a perspective bottom view of a pallet;

(4) FIG. 3 shows a perspective top view of a first embodiment of the invention with two stopping devices with the pallet indicated above in the locking position;

(5) FIG. 4 shows a top view of a stopping device according to FIGS. 2 and 3 in locking position (base plate of pallet not shown);

(6) FIG. 5 shows a plan view of the stopping device of FIG. 4 in the release position;

(7) FIGS. 6a, 6b, 6c., and 6d show different embodiments of locking elements in locking position, shown in plan view and schematically (as well as dashed in a release position);

(8) FIG. 7 shows a cut partial front view of a second embodiment with horizontally running stop element and horizontally running stopping elements in locking position, and

(9) FIG. 8 shows the same view of the stopping device of FIG. 7 in the release position.

DETAILED DESCRIPTION OF THE INVENTION

(10) In FIG. 1 a section of an accumulating conveyor 1 with an upper run 2 and a lower run 3 is shown in perspective from above, which together form an upper conveyor track 4 and a lower conveyor track 5 for pallets 20 one behind the other. The upper run 2 and the lower run 3 are connected at both front ends (only one is shown) by essentially semicircular reverse sections 6. In the upper run 2, two horizontally spaced running rails 14 run parallel to each other, and in the lower run 3, two horizontally spaced running rails 15 run parallel to each other. In each case, a running rail 14 of the upper run 2 is arranged above a running rail 15 of the lower run 3, one such pair of running rails 14, 15 being connected by means of struts of a frame 13. One running rail 14 of each upper run 2 is connected to one running rail 15 of each lower run 3 by a link 18 arranged in each of the reverse sections 6. The accumulating conveyor 1 thus has two side sections 17, in each of which the side sections of a pallet 20 are guided and thus an endless circulation of the pallets 20 is realized. It should also be noted that on the side of the reverse section 6 facing away from the motor 8, a cover 12 is fitted in front of the deflecting element 7.

(11) In the reverse sections 6, in each side section 17, there are also deflecting elements 7 in the form of sprockets mounted on a common shaft 10, which defines a rotation axis 16. The shaft 10 is driven by a motor 8 and an intermediate gear transmission 11. Endless tension elements 9 in the form of three-track endless chains thus run in each side section 17 and take pallets 20 with them, which circulate endlessly in the accumulating conveyor 1. As can be seen from FIG. 2, the pallets 20 have gear wheels 25 for this purpose, which are supported on side plate 24 in the area of the two transverse sides of each pallet 20. The gear wheels 25 are each coupled to a hysteresis clutch 26 which is provided on the side of each side plate 24 facing away from the gear wheels 25. These hysteresis couplings are described in more detail in WO 2004/000698 A1. If no exceptional force is applied to the gear wheels 25, the gear wheels do not rotate in the tension elements 9 but act as rigid latches engaging in the tension elements to propel the pallet 20 forward. If an obstacle, such as a stationary pallet 20 or a stopping device, appears, the gear wheels 25 begin to rotate so that the pallet 20 does not continue to move while the gear wheels 25 rotate in place. Instead of hysteresis clutches 26, other, conventional clutches such as friction clutches can of course also be used.

(12) For a smooth running of the pallets 20 in the running rails 14, 15 as well as the link 18, they have a roller 23 on their underside 22 in each of the four corner areas, see e.g., FIG. 2.

(13) As can also be seen from FIG. 2, a first positive locking element 30 is provided centrally on the underside 22 of each pallet 20 for deflecting the pallets 20 in the reverse sections 6, which interacts with a second positive locking element 35 provided in both reverse sections 6. The first positive locking element 30 comprises a rigid component 31 which is elongated and extends in the transport direction of pallet 20. The rigid component 31 has a toothed segment 32 with nine teeth present, which form a concave envelope curve with a constant radius. The second positive locking element 35 comprises a gear wheel 36 according to the present embodiment, which is arranged centrally on the shaft 10 between the two deflection elements 7 and is driven synchronously with them. A chain 37 is tensioned on the gear wheel 36, which preferably has little or no play. When a pallet 20—for example from the upper run 2—is driven into a reverse section 6, a positive fit is produced between the teeth of the toothed segment 32 and the chain 37. Further de-tails on this embodiment are disclosed in the DE 10 2014 106 956 A1 mentioned at the beginning.

(14) On the underside 22 of each pallet 20 there are two stop elements 40 spaced in the transverse transport direction QR and arranged on both sides of the first positive locking element 30. The cylindrical stop elements 40, which are preferably made of a metal, project vertically downwards from the underside 22 of pallet 20 (with pallet 20 running on the upper run 2). Furthermore, the stop elements 40 are each enclosed centrally in likewise cylindrical metallic basic bodies 41 (see FIG. 3), which lie directly against the underside 22 of pallet 20. Each stop element 40 can be firmly connected to the base plate 21 of pallet 20 with a screw 42 or other fastening means.

(15) As they move forward, the stop elements 40 each collide with one or more stopping elements 51 of an inventive stopping device 50, which is explained in more detail below. The pallet 20 is stopped by means of the stopping device 50, wherein the two gear wheels 25 of the stationary pallet 20 then begin to rotate when the tension elements 9 continue to run.

(16) As can be seen in particular from FIG. 3, two stopping devices 50 spaced in transport transverse direction QR are attached to an upper plate 39 of an essentially C-shaped cross strut 38 of a plate edge construction, which runs between the both side sections 17 and between upper run 2 and lower run 3, in accordance with the exemplary embodiment shown there. Each stopping device 50 comprises a motor 52 designed as an electric motor, which drives an endless drive belt 53. Each of these two drive belts 53 is in turn tensioned around an output disc 54 to rotate it around a fixed, vertically aligned rotation axis 55 by means of a shaft (not shown). In addition, each of the two motors 52 is connected to a central machine control (not shown), which controls the two motors and thus brings the stopping elements 51 into a locking or release position for locking or releasing the stop element 40.

(17) A platform 56 is arranged on each of the two output pulleys disc 54, on which two stopping elements 51, arranged at a distance from each other, are fastened and rise vertically. The stopping elements 51 are designed as cylindrical round bushings, i.e., rotatably mounted around their respective longitudinal axis.

(18) In the position shown in FIG. 4—FIGS. 4 and 5 each show only one stopping device 50 in plan view without the base plate 21 and the basic body 41—the two stopping elements 51 are in the locking position. Here they are arranged next to each other at the same height, i.e., both are aligned with each other in transport transverse direction QR. The distance between the two stopping elements 51 is smaller than the diameter of the stop element 40, so that the stop element 40 and thus the entire pallet 20 are stopped by the stopping elements 51 in this locking position.

(19) The rotation axis 55 of the output disc 54 coincides with the longitudinal axis of the stop element 40 in the locking position shown in FIG. 4. The stop element 40 is therefore encircled by the stopping elements 51 without being displaced in a transverse direction by the stopping elements 51.

(20) When the two motors 52 are switched on, the two stopping elements 51 rotate together with the output disc 54, moving around the rotation axis 55. The stopping elements 51 roll off the cylindrical outer surface of the stop element 40 and run through a curved path in the form of a circular path. This movement causes the stopping elements 51 to move from the locking position shown in FIG. 4 to a release position shown in FIG. 5. A first release position is already reached when both stopping elements 51 have passed the stop element 40 against the transport direction TR.

(21) For the embodiment shown in FIGS. 3-5, the motors 52 of both stopping devices 50 must be actuated in the same way (synchronously or counter-clockwise) in order to transfer the stopping elements 51 of both stopping devices 50 from the locking position to the release position.

(22) The return of the stopping elements 51 from the/or from a release position to a locking position is preferably carried out by turning the output disc 54 further by the corresponding angle of rotation, so that a final 360° rotation of the output disc results. The corresponding control of the two motors 52 is in turn carried out by the central machine control. According to this exemplary embodiment, each stopping device 50 can be precisely moved into its respective locking position by means of the associated motor 52 on the basis of signals from an inductive sensor 58, in each case. For this purpose, the inductive sensors 58 are arranged on the underside of the upper plate 39 of the cross strut 38 and register a respective sensor flag assigned to them (not shown). For this purpose, each of the two sensor flags is also arranged on the underside of the upper plate 39 at the same level as the respective associated inductive sensor 58 and coupled to the respective associated platform 56 via the shaft mentioned above, through which the axis of rotation 55 runs, so that both the platform 56 and the associated sensor flag rotate about this axis of rotation 55. Each sensor flag is aligned so that it faces the associated inductive sensor 58 exactly when the stopping device 50 is in the locked position. Thus, if each inductive sensor 58 registers that the associated sensor flag is exactly opposite it, the central machine control sends a stop command to the respective motor 52.

(23) The embodiments shown in FIGS. 2-5, and in particular the embodiment of the axis of rotation 55 and the longitudinal axis of the stop element 40 (when in the locking position or in the release position, but not yet moved on) aligned with each other or falling together, require only extremely low power consumption, so that it is sufficient if the motors 52 are designed as 24V electric motors.

(24) FIGS. 6a-6d show different embodiments of stopping elements 51 schematically and in plan view, whereby the stopping elements 51 are shown in their respective locking position with solid lines and in free position in dashed lines.

(25) The embodiment according to FIG. 6a corresponds to that of FIGS. 3-5: The two cylindrical stopping elements 51 are arranged at a distance from each other and block the stop element 40 (and thus the pallet 20) from continuing in the transport direction TR. The stop element 40 is released when both stopping elements 51 are rotated by approximately 150° around the rotation axis 55 as shown here. Here the stopping elements 51 roll off the cylinder surface of the respective stop element 40. A further rotation in the same direction of rotation or in the opposite direction brings the stopping elements 51 back into a locking position.

(26) The embodiment according to FIG. 6b has only one stopping element 51a, which is designed as a hollow cylinder section and in the locking position rests with two edges at different points S1, S2 along the circumference of the stop element 40. In order to achieve this, the inner radius of the hollow cylinder section is smaller than the radius of the stop element 40. The stopping element 51a, which is rotated into a release position around the axis of rotation 55, is shown dashed again.

(27) FIG. 6c shows a further embodiment of a stopping element 50b, which in turn is designed as a hollow cylinder section, although the inner radius of this hollow cylinder section corresponds to the radius of the stop element 40, which in turn is designed as a cylinder. For this reason, the hollow cylinder section with its entire convex surface lies on the outside of the stop element 40. When rotating around the rotation axis 55, the stopping element 50b can be brought into the dashed release position—and also back into the locking position.

(28) The embodiment of FIG. 6d shows in plan view a stopping element 51c with three walls 59 arranged perpendicular to each other, which form a kind of cage open on one side for a stop element 40. When turned 180° around the rotation axis 55, the stopping element 51c moves into the release position and can then be rotated back into the locking position.

(29) FIGS. 7 and 8 each show cut partial front views of a second embodiment with horizontally running or aligned stop element 40 and two horizontally running or aligned stopping elements 51 in locking position or in release position. The stop element 40 is connected to the pallet 20 via a spacer 43 attached to the underside 22 of the pallet 20 and projecting downwards from this by means of a screw 42 only indicated. Furthermore, by means of fastening elements 57a, a support piece 57 with a C-shaped cross-section and bridging the two rails 14, 15 is provided, to which the stopping device 50 with the rotatable platform 56 and the two stopping elements 51 located thereon is fastened, which are arranged in the travel path of the stop element 40 when the pallet 20 travels. The platform 56 is rotatably mounted in a bearing block 56a, which is attached to the support piece. The stopping device 50 according to FIGS. 7 and 8 is basically designed according to the first embodiment of FIGS. 2-5, except that the two stopping elements 51 are now aligned or run in a horizontal direction. In FIG. 7 the two stopping elements 51 have moved into their locking position, i.e., in front of the stop element 40, while they are in the release position according to FIG. 8 after a circular path of 180° (see the direction of rotation f1 indicated by a double arrow in FIG. 7), so that the pallet 20 can continue to move (in the direction of the observer).

(30) In FIGS. 7 and 8, only in the area of one transverse side of a pallet 20 is a stop element 40 and an opposite stopping device 50 fixed to the rails 14, 15 provided. It is possible that in the area of the other transverse side of the pallet 20 a corresponding stop element 40 and a corresponding stopping device 50 fixed to the opposite rails 14, 15 are also provided.

(31) Not shown in any of the figures are sensors advantageously provided for determining the positions of pallets 20 along their path in the accumulation conveyor 1. The sensors can give corresponding signals to a central machine control, which then activates the motors 52 in order to transfer the stopping elements 51 from one or more stopping devices 50 either from a locking position to a release position or vice versa. It is of course possible that several stopping devices 50 are provided along the travel path to prevent pallets from continuing their journey at different locations.

(32) The invention was explained in more detail using exemplary embodiments. However, as far as possible, the features of the different embodiments to create new embodiments that belong to the invention can be combined. In addition, the invention also includes modifications within the claims. For example, it is of course possible that only one single stop element 40 is provided on the underside of the pallets, and that only one single stopping device 50 is provided for locking and releasing a stop element 40 and thus the corresponding pallet 20. This can, for example, be designed as in FIGS. 3 and 4 or FIGS. 7 and 8, i.e., without a further stopping device 50 on the underside of pallet 20.

REFERENCE SIGN LIST

(33) 1—Accumulating conveyor 2—Upper run 3—Lower run 4—Upper conveyor track 5—Lower conveyor track 6—Reverse section 7—Deflecting element 8—Motor 9—Tension element 10—Shaft 11—Gear transmission 12—Cover 13—Frame 14—Running rail 15—Running rail 16—Rotation axis 17—Side section 18—Link 20—Pallet 21—Base plate 22—Underside of the pallet 23—Rollers 24—Side plate 25—Gear wheel 26—Hysteresis clutching 30—First positive locking element 31—Rigid component 32—Toothed segment 35—Second positive locking element 36—Gear wheel 37—Chain 38—Cross strut 39—Upper plate of the cross strut 40—Stop element 41—Basic body 42—Screw 43—Spacer 50—Stopping device 51—Stopping element 51a—Stopping element 51b—Stopping element 51c—Stopping element 52—Motor 53—Drive belt 54—Output disc 55—Rotation axis 56—Platform 56a —Bearing block 57—Support piece 57a —Fastening elements 58—Sensor 59—Wall TR—Transport direction QR—Transverse transport direction S1—Resting position S2—Resting position f1—Direction of rotation