ROTATING INDEXING APPARATUS FOR CONVEYING SAND MOLDS

Abstract

An indexing transfer station for a sand mold conveyor system, and method of conveying. The indexing transfer station rotates between two or more angled conveyors to position the sand mold for further downstream movement. The indexing transfer station includes resting pads for the sand molds, spaced apart to allow a walking transfer rail of a first conveyor to place the sand mold and, upon rotation, to allow a walking transfer rail of a second conveyor each to position under the sand mold for lifting.

Claims

1. An apparatus for conveying sand molds, comprising: two resting pads configured to receive a sand mold thereon, the resting pads spaced apart and rotatable from a first angular position to a second angular position.

2. The apparatus according to claim 1, wherein the first angular position is aligned with a first transfer conveyor for the sand mold, and the second angular position is aligned with a second transfer conveyor for the sand mold.

3. The apparatus according to claim 2, wherein the resting pads rotate 90°.

4. The apparatus according to claim 1, further comprising a rail channel disposed between the resting pads, configured to rotate and alternatively receive a transfer rail of each of a first transfer conveyor and a second transfer conveyor.

5. The apparatus according to claim 4, further comprising a roller extending within the rail channel to receive the transfer rail thereon.

6. The apparatus according to claim 1, further comprising: a base; a rotator is connected to and above the base; and a frame connected to the rotator, wherein the resting pads are connected above the frame, wherein the frame rotates with respect to the rotator and base.

7. The apparatus according to claim 6, further comprising a bearing connecting the frame to the rotator.

8. The apparatus according to claim 6, further comprising a rail channel disposed between the resting pads, configured to alternatively receive upon rotation a transfer rail of each of a first transfer conveyor and a second transfer conveyor, wherein a portion of the frame forms a bottom of the rail channel, and a roller is connected to the frame and extending within the rail channel to alternatively receive thereon the transfer rail of each of the first transfer conveyor and the second transfer conveyor

9. The apparatus according to claim 1, wherein one of the two spaced apart resting pads comprises truncated outer corners.

10. An apparatus for conveying sand molds, comprising: a first transfer conveyor oriented in a first direction and including a first transfer rail movable with respect to at least one fixed rail; and a rotating junction transfer station disposed at an end of the first transfer conveyor.

11. The apparatus according to claim 10, wherein the junction transfer station includes two resting pads configured to hold a sand mold, wherein the transfer rail of the first transfer conveyor is movable between the spaced apart resting pads of the junction transfer station.

12. The apparatus according to claim 11, wherein the junction transfer station comprises a roller adapted to receive the first transfer rail.

13. The apparatus according to claim 10, further comprising a second transfer conveyor in conveying combination with the first transfer conveyor and oriented in a second direction that is different than the first direction, the second transfer conveyor including at least one transfer rail movable with respect to at least one fixed rail, wherein the rotating junction transfer station is disposed between the first and second transfer conveyors.

14. The apparatus according to claim 13, wherein one of the two spaced apart resting pads, which is disposed toward the first and second transfer conveyors during rotation, comprises truncated outer corners to allow rotation.

15. The apparatus according to claim 4, wherein the junction transfer station includes two spaced apart resting pads for holding a sand mold, wherein the central transfer rail of each of the first and second transfer conveyors is movable between the spaced apart resting pads via rotation of the rotating junction transfer station.

16. The apparatus according to claim 5, wherein each of the first and second transfer conveyors comprises two outboard rails and a central transfer rail movable between the two outboard rails.

17. The apparatus according to claim 10, wherein the rotating junction transfer station comprises a sensor mechanism adapted to sense the presence of the sand mold on the resting pads to initiate rotation.

18. A method for conveying a sand mold, the method comprising: moving the sand mold in a first direction with a first transfer conveyor via a transfer rail reciprocating with respect to at least one fixed rail; moving the sand mold onto resting pads of a junction transfer station disposed at an end of the first transfer conveyor; and rotating the resting pads and the sand mold for moving the sand mold in a second direction that is at an angle to the first direction.

19. The method according to claim 18, further comprising: lifting the sand mold off the at least one fixed rail with the transfer rail; moving the transfer rail and the lifted sand mold in a downstream direction; lowering the lifted sand mold onto the resting pads; lifting the sand mold off the resting pads via a second transfer rail after the rotating.

20. The method according to claim 18, further comprising: lifting the sand mold off the at least one fixed rail with the transfer rail; moving the transfer rail with the lifted sand mold in a downstream direction between the resting pads; lowering the lifted sand mold onto the resting pads; moving the first transfer conveyor transfer rail from between the resting pads; upon the rotating the resting pads, moving a second transfer conveyor transfer rail under the sand mold between the resting pads; and lifting the sand mold off the resting pads with the second transfer conveyor transfer rail.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] FIG. 1 is a top view of an accumulating mold conveyor according to one embodiment of this invention.

[0019] FIG. 2 is a side view of an accumulating mold according to one embodiment of this invention.

[0020] FIGS. 3 and 4 each illustrate accumulating mold conveyor sections according to one embodiment of this invention.

[0021] FIGS. 5A and 5B illustrate an accumulating mold conveyor according to one embodiment of this invention.

[0022] FIGS. 6 and 7 show accumulating mold conveyor sections according to FIGS. 5A and 5B.

[0023] FIGS. 8-10 illustrate an indexing mechanism according to one embodiment of this invention.

[0024] FIGS. 11-14 illustrate an indexing mechanism according to one embodiment of this invention.

DEFINITIONS

[0025] Within the context of this specification, each term or phrase below will include the following meaning or meanings.

[0026] References herein to “conveying combination” are to be understood to refer to a combination of two elements, such as two conveyors, whereby an item conveyed by one element is transferable to the other element for continued conveyance to the intended destination.

[0027] References herein to “upstream” and “downstream” are to be understood with reference to directions of travel of molds on a conveyor. “Upstream” refers to a direction toward a place of origin, such as a mold forming device, and “downstream” refers to a direction toward a place of destination.

DESCRIPTION OF FIGURES

[0028] Referring to FIG. 1, this invention provides a conveyor assembly, shown as accumulating mold conveyor 20, for transporting sand molds from a first station 16, such as a sand mold forming station, to a second station 18, such as a metal pouring station.

[0029] Accumulating mold conveyor 20 includes first transport conveyor 22 oriented in a first direction, and second transfer conveyor 24 oriented in a second direction. As will be appreciated, aspects of the invention can be applied to an accumulating conveyor with only one transfer conveyor or more than two. In the embodiment of FIG. 1, first and second transfer conveyors 22 and 24 are disposed perpendicular to each other; however, the conveyors of this invention can be disposed at other angles, depending on need. First transfer conveyor 22 has an upstream end 30 that is to be disposed toward first station 16, and a downstream end 32 opposite the upstream end 30. Similarly, second transfer conveyor 24 has an upstream end 34 and an opposing downstream end 36. Sand molds travel along the conveyors of this invention from an upstream end to a downstream end. Downstream end 32 of first transfer conveyor 22 is in conveying communication with upstream end 34 of second transfer conveyor 24, such that a sand mold is transferred during operation from downstream end 32 of first transfer conveyor 22 to upstream end 34 of second transfer conveyor 24.

[0030] First transfer conveyor 22 includes first outboard rail 46 spaced apart from second outboard rail 48. Outboard rails 46 and 48 can each be formed as a single rail member or from a plurality of smaller individual rail members. A central rail channel 50 is formed between first outboard rail 46 and second outboard rail 48. Central transfer rail 52 is disposed within central rail channel 50, and is movable therein and between the two fixed outboard rails 46 and 48. Second transfer conveyor 24 includes components identical or at least similar to first transfer conveyor 22. These components are described with reference to first transfer conveyor 22, and identified by element reference numbers associated with a prime (′).

[0031] A pusher station 55 is optionally disposed at the end 36 of the second transfer conveyor 24. The pusher station 55 includes a pusher 40 that moves each mold from the conveyor 24 to the second station 18. As shown in FIG. 1, each of the stations 16 and 18 are located laterally relative to the conveyor ends 30 and 36, respectively. The pusher moves in a direction perpendicular to the conveyance direction of the second transfer conveyor 22 to push the mold onto the second station 18. An optional lift mechanism with a lift plate or platform 45 can be used if the second station 18 is at a different height from the first station 16, such as shown in FIG. 2.

[0032] The accumulating mold conveyor of this invention is not limited to the configuration and number of fixed and moveable rails shown in FIG. 1. For example, the center rail(s) can be fixed in place and not moveable, with two or more outboard rails moveable with respect to the fixed center rail(s). Also, in one embodiment of the invention, two moveable transfer rails are disposed on either side of a fixed center rail, and each of the moveable transfer rails is between the center rail and a further fixed outboard rail (e.g., five total rails).

[0033] FIG. 2 is a side view of accumulating mold conveyor 20 showing molds 25 thereon. As shown in FIG. 2, the second station 18 has a receiving surface that is higher than the mold conveyor 20. The height of the mold conveyor 20 is chosen due to the height of first station 16, and in FIG. 2, the pusher station 55 is incorporated into or with an optional lift mechanism, forming a lift and transfer station 55. As will be appreciated, the lift station could additionally or alternatively be incorporated elsewhere along the conveyor, such as at the end near the first station or at a junction of two or more conveyors, depending on need.

[0034] As shown in FIG. 3, the central transfer rail 52 is a reciprocating rail that includes a rail frame 54, including crossbars 53, disposed upon a plurality of rollers 56. Each transfer conveyor includes at least one pressurized fluid piston 58, e.g., a hydraulic piston, having a moveable piston arm 60 connected to frame 54 by connector 62. Piston arm 60, and thus frame 54 and central transfer rail 52, is movable between an upstream position and a downstream position. In embodiments of this invention, the central transfer rail is movable between three positions, a central position, an upstream position, and a downstream position.

[0035] A plurality of sand mold carrier plates 70 is disposed along the frame 54. Each of carrier plates 70 is attached to the rail frame 54 by one of a plurality of pressurized fluid lift mechanisms 72, e.g., a pneumatically actuated piston. Each of pressurized fluid lift mechanisms 72 is adapted to lift a corresponding one of carrier plates 70, and a sand mold thereon, to a lifted position above or higher than the outboard rails 46 and 48, and then to lower the corresponding one of carrier plates 70 to lowered position. In the lowered position, sand molds 25 are disposed on outboard rails 46 and 48. In the lifted position, sand molds 25 are moved to, and then lowered onto, a downstream position on outboard rails 46 and 48.

[0036] The lifting distance of the sand molds 25 can vary depending on need. In one embodiment of this invention, the sand molds 25 are lifted less than an inch above the outboard rails 46 and 48, and more desirably about 1/16.sup.th of an inch. In another embodiment, the sand molds are not actually lifted off the outboard rails, but the carrier plates place upward pressure on the sand molds to reduce friction and allow the sand molds to more easily slide along the outboard rails.

[0037] Sand molds 25 are moved along first transfer conveyor 22 by lifting a sand mold 25 off outboard rails 46 and 48 at a first of resting positions with a corresponding one of carrier plates 70, moving the sand mold in a downstream direction with central transfer rail 52 to dispose sand mold 25 over a second of resting positions 80, and lowering sand mold 25 onto outboard rails 46 and 48 at the second of resting positions 80. Central transfer rail 52 then moves back to the first position, and the process repeats to incrementally move, or “walk,” sand mold 25 in a downstream direction on first transfer conveyor 22.

[0038] Referring to FIGS. 1 and 2, lateral entry of the molds 25 onto the conveyor 20 provides additional issues over colinear end entry. Moving the molds from the side can result in a lower leading edge of the mold catching on the rails, particularly the outboard rail on the far side from the entry point. This is due to a lower position of the central rail between the outboard rails. Embodiments of this invention include an optional adjustment mechanism for the central rail, to lift the central rail even with the outboard rails, at least at the entry position.

[0039] FIG. 3 shows an adjustment mechanism 100 in combination with the first transfer rail 52. The mechanism includes a leveling cylinder 102 on the conveyor frame 35 that provides vertical movement (or perpendicular to the conveying direction) of the end of the first transfer rail 52. The cylinder 102, connected by plate 105 to crossbars 53, raises the rail frame 54 to level a first pad 70 with the corresponding outboard rail 48. The frame 54 may be lifted off rollers 56, and then lowered again after the mold 25 is in the conveying position on the conveyor 20.

[0040] A plurality of optional sensor mechanisms can be disposed along each transfer conveyor. Each of the plurality of sensor mechanisms is desirably disposed in sensing combination with one of the resting positions. Sensor mechanisms detect the presence of sand molds along the transfer conveyor, and can be used to actuate lifting of a corresponding carrier plate when a sand mold is disposed above the corresponding carrier plate. Thus, in one embodiment of this invention, a carrier plate is not lifted unless a sand mold is present above. Various and alternative sensor mechanisms are available for the use in the accumulating mold conveyor of this invention, such as, without limitation, motion sensors using visible or infrared light or weight sensors disposed beneath outboard rails.

[0041] Referring to FIGS. 1 and 3, accumulating mold conveyor 20 includes first junction transfer station 86 disposed between downstream end 32 of first transfer conveyor 22 and upstream end 34 of second transfer conveyor 24. Junction transfer station 86 includes an indexing unit 200. When the central transfer rail 52 of first transfer conveyor 22 is moved out from first junction transfer station 86, the indexing apparatus rotates to receive the central transfer rail 52′ of second transfer conveyor 24. When the rotation frame 202 and pads 88 of the first junction transfer station 86 are rotated relative to base 204, central transfer rail 52′ of second transfer conveyor is able to move into the indexing apparatus and lift sand mold 25 off resting pads 88, thereby perpendicularly transferring sand mold 25 to second transfer conveyor 24. The configuration of the indexing unit 200, and resting pad(s) 88 will depend on, and desirably coordinate with, the configuration of the accumulating conveyor and/or transfer rail(s). The indexing unit 200 can include a sensor 214 for determining that a sand mold is placed thereon or removed therefrom, such as for initiating rotation between the two (or more) transfer conveyors.

[0042] Accumulating mold conveyor 20 includes second junction resting station 90 disposed at the downstream end 36 of second transfer conveyor 24 and within the lifting and transfer station 55. Second junction resting station 90 can includes four spaced apart resting pads 92 for holding sand molds 25. Any included lift platform can have an X- or cross-shaped configuration with extensions that fit and lift between pairs of the four pads 92 to lift the mold vertically (perpendicular to the conveying direction) to the pusher 40. Pusher 40, which can include a hydraulically activated pusher arm, pushes sand molds 25 off the second junction resting station 90 and onto a receiving surface/platform (e.g., add-on platform 144 of FIG. 11) of the associated station 18. Further details on the adjustment mechanism and the lifting mechanism, are contained in co-pending application Ser. No. 16/720,307, and herein incorporated by reference.

[0043] This invention further includes a method for conveying a sand mold. The method of this invention uses an accumulating conveyor, such as described above, including a first transfer conveyor in conveying combination with a second transfer conveyor, each of the first and second transfer conveyors comprising two outboard rails and a central transfer rail movable between the two outboard rails.

[0044] In one embodiment of this invention, referring to FIG. 1, a first sand mold forming machine deposits first sand mold 25 on first transfer conveyor 22. In one embodiment of this invention, sand mold 25 is placed directly onto first transfer conveyor 22, without an optional bottom board, such as are known to those skilled in the art. Sand mold 25 moves along first transfer conveyor 22 in a first downstream direction. First transfer conveyor 22 moves sand mold 25 by lifting the sand mold off outboard rails 46 and 48 with central transfer rail 52, moving central transfer rail 52 and the lifted sand mold 25 in the first downstream direction, and lowering the lifted sand mold 25 onto outboard rails 46 and 48. The steps for moving first sand mold 25 are repeated until first sand mold 25 is placed by central transfer rail 52 onto first junction transfer station 86. Upon placing first sand mold 25 onto first junction transfer station 86, the central transfer rail 52 moves back upstream and out from under sand mold 25.

[0045] The transfer station indexing apparatus 200 rotates to allow further downstream mold movement. Central transfer rail 52′ of second transfer conveyor 24 then moves under first sand mold 25 to transfer first sand mold 25 to second transfer conveyor 24. Central transfer rail 52′ lifts first sand mold 25 off first junction resting station 86 and moves first sand mold 25 along second transfer conveyor 24 in the manner discussed above for first transfer conveyor 22, but in a second downstream direction, that is perpendicular to the downstream direction of first transfer conveyor 22. The steps for moving first sand mold 25 along second transfer conveyor 24 are incrementally repeated until first sand mold 25 is placed by central transfer rail 52 onto second junction resting station 90. Upon placing first sand mold 25 onto second junction resting station 90, central transfer rail 52 moves back upstream and out from under first sand mold 25.

[0046] As will be appreciated by those skilled in the art following the teachings herein provided, various and alternative sizes, shapes, and configurations are available for the mold accumulating conveyor, transfer conveyors, junction resting/transfer stations, leveling mechanisms, lift mechanisms, pusher mechanism(s), and indexing apparatus of this invention.

[0047] FIG. 5A shows an accumulating conveyor 20 according to another embodiment of this invention. The conveyor 20 includes an indexing transfer station 86, shown with an illustrated circle 201 representing the rotational movement of the indexing unit, as needed along the full 360° circle , but desirably back and forth between the two transfer conveyors (e.g., 90°). FIG. 5B shows the indexing apparatus 200 separate from the conveyor 20. FIGS. 6 and 7 show side views of the station 86 and indexing apparatus 200, from two different views.

[0048] Referring to FIG. 6, the indexing apparatus 200 includes resting pads 88 for the mold 25. The resting pads are mounted parallel on a rotation frame 202. The rotation frame 202 rotates about base 204 via a rotator 210 connected between the base 204 and rotation frame 202. As illustrated between FIGS. 6 and 7, each transfer rail 52, 52′ of the conveyor 20 can move between the parallel pads 88, in the correspondingly rotated position, to move the mold 25 on or off the pads 88. The corresponding rotated position refers to a position where the pads 88 are parallel to the relevant transfer rail 52 or 52′, such that than one of the rails 52 or 52′ can move therebetween. When the indexing apparatus 200 rotates, the other of the transfer rails 52 or 52′ is then able to move therebetween.

[0049] FIG. 8 is a partially exploded view of an indexing apparatus 200 according to one embodiment of this invention. The rotation frame 202 includes two resting pads 88, held elevated to allow transfer rails to move therebetween in rail channel 205. The frame 202 includes roller brackets 208 for rollers 212 that support transfer rail 52, 52′ movement in rail channel 205, such as supporting the undersides of the two sides of rail frame 54, between the pads 88. The frame 202 connects to a rotator 210 (representatively illustrated) via bearing plate 220. The rotator is suitably fixed to the base 204.

[0050] The angular rotation of the indexing apparatus 200 can be varied, depending on need. As shown in the illustrated embodiments, the desired rotation is 90°, between the perpendicular transfer conveyors 22 and 24. As will be appreciated, the rotating indexing apparatus of this invention can be used to provide additional angles between the transfer conveyors 22 and 24, such as, for example, between 45° and 180°. The indexing apparatus can also be used to rotated between more than two transfer conveyors. As shown in FIG. 8, at least one of the resting pads 88 includes truncated corners to facilitate rotation and keep the resting pad from hitting the transfer conveyors 22 and 24 during rotation back and forth over the 90° between the two transfer conveyors 22 and 24. The truncated corners are shown as two outer corners of the otherwise rectangular resting pad 88 being cut short at an angle across the rectangle corners, but the corners or outer edge of the resting pad can also be curved or otherwise shaped to promote rotation in a desired placement distance from the ends of the transfer conveyors 22 and 24. For rotation between more than two transfer conveyors, or full 360° rotation, both resting pads, or at least the corners thereof, can need to be shaped as well to allow the larger angular range of rotation.

[0051] FIGS. 9 and 10 show top and side views of the collar 220. The bearing plate 220 includes a center opening 222 for a rotator shaft, and keyway slot 224 to allow for proper alignment and/or connection with the frame 202 and/or rotator 210.

[0052] FIGS. 11-13 show an assembled indexing apparatus according to one embodiment of this invention. As seen in FIG. 13, the bearing plate 222 is connected to the rotator 210 by a cylinder plate 230, shown also in FIG. 14. The rotation frame 202 rotates via, and about an axis of, the rotator 210.

[0053] Thus, the invention provides a mold accumulating conveyor that feeds sand molds from multiple sand mold forming machines to a single metal pouring station. The accumulating mold conveyor of this invention improves efficiency of casting by, for example, allowing for a sand mold casting apparatus to continually run, even while one associated sand mold forming machine is offline The invention further provides a more flexible accumulating mold conveyor installation, such as between machine stations of two different manufacturers. The apparatus and method allow for efficient change of direction, moving between accumulating conveyors in angled configurations.

[0054] It will be appreciated that details of the foregoing embodiments, given for purposes of illustration, are not to be construed as limiting the scope of this invention. Although only a few exemplary embodiments of this invention have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention, which is defined in the following claims and all equivalents thereto. Further, it is recognized that many embodiments may be conceived that do not achieve all of the advantages of some embodiments, particularly of the preferred embodiments, yet the absence of a particular advantage shall not be construed to necessarily mean that such an embodiment is outside the scope of the present invention.