OBJECT LOADING AND UNLOADING CONVEYANCE DEVICE

• US 20080075577A1
• Filed: 09/14/2007
• Published: 03/27/2008
• Est. Priority Date: 09/22/2006
• Status: Active Grant

• Current Assignee: Daifuku Company Limited
• Original Assignee: Daifuku Company Limited
• Inventors: Shimizu, Yoshio, Ishioka, Yasushi
• Granted Patent: US 7,748,514 B2
• Time in Patent Office: Days
• US Class Current: 414/792.8
• CPC Class Codes: B65G 47/46 and distributing, e.g. automatically, to desired points in tube mail systems B65G51/36
• CPC Class Codes: B65G 47/61 for articles

Abstract

A conveyance device suitable for an automobile assembling plant has an object loading and unloading conveyance device between a hanging conveyance line, in which a pallet supporting a door is conveyed while being supported by a hanging hanger, and an object loading and unloading position on the floor side. The conveyance device also has a pallet transferring position set above the object loading and unloading position, a horizontal conveyance device, which conveys a pallet between the pallet transferring position and a hanger stop position, and an elevating conveyance device which conveys the pallet vertically between the object loading and unloading position and the pallet transferring position. The elevating conveyance device rotates a plurality of pallet mounting bases in an endless cyclic elevating path while holding these in erect postures, and the pallet mounting bases are arranged at even intervals equal to the distance between the upper and lower positions.

Claims

1. An object loading and unloading conveyance device which conveys an object together with a pallet between a hanging conveyance line in which the pallet supporting the object is conveyed while being supported by a hanging hanger and an object loading and unloading position set on the floor side, comprising a horizontal conveyance device which conveys the pallet substantially horizontally between a pallet transferring position set above the object loading and unloading position and a hanger stop position in the hanging conveyance line, and an elevating conveyance device which conveys the pallet vertically between the object loading and unloading position and the pallet transferring position, wherein the elevating conveyance device includes a plurality of pallet mounting bases for supporting the pallet and an endless cyclic elevating path which cyclically moves vertically the pallet mounting bases, and a drive means which rotatively moves the respective pallet mounting bases while holding these in erect postures in the endless cyclic elevating path, and the pallet mounting bases are arranged at even intervals equal to the distance between the object loading and unloading position and the pallet transferring position.

2. The object loading and unloading conveyance device according to claim 1, wherein the number of pallet mounting bases provided in the endless cyclic elevating path of the elevating conveyance device is three.

3. The object loading and unloading conveyance device according to claim 1, wherein on each of the pallet mounting bases of the elevating conveyance device, a pair of roller rails which support left and right sides of the pallet movably horizontally are provided.

4. The object loading and unloading conveyance device according to claim 3, wherein the pallet is structured so as to include a pair of left and right side frames, a joint member which joins the side frames to each other, and a pair of left and right projecting plates projecting outward from the upper sides of the left and right side frames, and the pair of left and right projecting plates are supported by the pair of left and right roller rails.

5. The object loading and unloading conveyance device according to claim 1, wherein the horizontal conveyance device is provided with pallet mounting base positioning means which engage with and disengage from engaged portions of the pallet mounting bases stopping at the pallet transferring position, and can hold the pallet mounting bases at a fixed stop level by engaging with the engaged portions.

6. The object loading and unloading conveyance device according to claim 5, wherein the horizontal conveyance device is provided with stoppers for preventing dropping of the pallet to the pallet transferring position side from the position on the horizontal conveyance device, the stoppers are urged and held at stopping positions, and the pallet mounting base positioning means is provided with a movable rod-like body which has, on its tip end, a fitting portion that can engage with and disengage from the engaged portion, and is movable in directions of moving away from and approaching the engaged portion, and a lever which is operated by the movable rod-like body when this movable rod-like body advances is provided on the stopper, and when the movable rod-like bodies advance and the fitting portions on the tip ends fit the engaged portions, the stoppers are switched to stop-releasing positions via the levers.

7. The object loading and unloading conveyance device according to claim 1, wherein the hanging hanger of the hanging conveyance line is structured to include a pallet fitting support which supports the pallet so as to fit and separate vertically, and the horizontal conveyance device can include a pallet loading and unloading conveyor which loads and unloads the pallet onto and from the hanger according to elevating and lowering movements with respect to the hanger stopping at the hanger stop position, and a pallet transferring means which transfers the pallet between the pallet loading and unloading conveyor and the pallet mounting bases stopping at the pallet transferring position.

8. The object loading and unloading conveyance device according to claim 7, wherein the pallet transferring means of the horizontal conveyance device includes a pallet carrying conveyor, a first movable body, and a second movable body, wherein the pallet carrying conveyor is connected to the pallet loading and unloading conveyor above the hanger stopping at the hanger stop position, the first movable body is constructed to reciprocate in the pallet conveying direction, and on the first movable body, a pallet pushing-out engagement piece is provided which propels the pallet onto the pallet mounting bases stopping at the pallet transferring position from the pallet carrying conveyor, and the second movable body moves to reciprocate in the pallet conveying direction, and on the second movable body, a pallet drawing-in engagement piece can be provided which propels the pallet from the position on the pallet mounting bases stopping at the pallet transferring position onto the pallet carrying conveyor.

9. The object loading and unloading conveyance device according to claim 8, wherein on the pallet mounting bases, a pallet latching means which automatically engages with the pallet transferred onto the corresponding pallet mounting base by the pallet pushing-out engagement piece to prevent the pallet from retreating is provided, and on the second movable body, an operating portion can be provided which switches the pallet latching means into an unlatching posture according to advancing thereof to the side of the pallet mounting base.

10. The object loading and unloading conveyance device according to claim 8, wherein the pallet carrying conveyor of the pallet transferring means is provided with stoppers for preventing dropping of the pallet to the pallet loading and unloading conveyor side from the position on this conveyor, and the stoppers are urged and held at stopping positions, and the pallet loading and unloading conveyor can be provided with operating portions which switch the stoppers to the releasing positions against the urging forces when the pallet loading and unloading conveyor rises to a position above the hanger stopping at the hanger stop position and is connected to the pallet carrying conveyor.

11. A conveyance method for conveying an object to the object loading and unloading position on the floor side from the hanging conveyance line by using the conveyance device according to claim 1, wherein by an operation of the elevating conveyance device when transferring an occupied pallet on which an object is mounted and put down from the hanger of the hanging conveyance line from the horizontal conveyance device to the elevating conveyance device and conveying it to the object loading and unloading position, an empty pallet from which an object was unloaded previously at the object loading and unloading position is simultaneously conveyed to the pallet transferring position, and this empty pallet is transferred from the elevating conveyance device to the horizontal conveyance device, and loaded onto an empty hanger of the hanging conveyance line in which the occupied pallet was unloaded from and is waiting.

12. A conveyance method for conveying an object from the object loading and unloading position on the floor side to the hanging conveyance line by using the conveyance device according to claim 1, wherein by an operation of the elevating conveyance device when transferring an empty pallet put down from the hanger of the hanging conveyance line from the horizontal conveyance device to the elevating conveyance device and conveying it to the object loading and unloading position, an occupied pallet P on which an object was mounted previously at the object loading and unloading position is simultaneously conveyed to the pallet transferring position and this occupied pallet is transferred from the elevating conveyance device to the horizontal conveyance device and loaded onto the hanger of the hanging conveyance line in which the empty pallet was unloaded from and is waiting.