JP5129951B2 - Pallet transport device - Google Patents

Description

  The present invention relates to a pallet conveying apparatus that conveys a pallet on which a workpiece is placed by a conveyor.

  Conventionally, when a workpiece such as a part is transported in a post-process, the workpiece is placed on a pallet formed so that the workpiece can be placed, and the pallet is placed on a workpiece transport conveyor provided with a transport belt. Was. In addition, a plurality of pallets are arranged and placed on the workpiece transfer conveyor so that workpieces can be sequentially placed thereon. Further, lifter devices are installed in the vicinity of both ends of the workpiece transfer conveyor, and the pallets that have finished transferring the workpiece are sequentially transferred to return conveyors installed at parallel positions below the transfer conveyor. It was replaced. Then, the pallet is returned to the delivery position of the workpiece conveying conveyor by the return conveyor, and is again transferred to the workpiece conveying conveyor by the lifter device and repeatedly used.

In addition, the pallet exchanging system disclosed in Patent Document 1 stops the pallets conveyed in a stacked state by the supply belt conveyor at a predetermined position facing the temporary placement table, and transfers the pallet to the temporary placement table by the robot apparatus. Then, the work is stored in order on the pallet by the robot hand. Then, after the work is stored in the pallet, the pallet is transferred to the discharge belt conveyor, and a predetermined number of pallets are stacked and discharged by the discharge belt conveyor.
JP-A-11-207561

  In the above conventional technique, when the pallet moving on the workpiece conveying conveyor reaches the supply end of the workpiece conveying conveyor, the pallet is lowered from the workpiece conveying conveyor, is transferred to the return conveyor, and reaches the upstream delivery position. I had to return the pallet. Similarly, when the pallet placed on the return conveyor returns to the delivery position of the workpiece transfer conveyor, it is necessary to unload the pallet from the return conveyor and replace the pallet on the workpiece transfer conveyor. For this reason, the overall configuration is complicated and expensive, and a plurality of apparatuses are combined. Therefore, a large installation space is required, and space efficiency is not good.

  Further, in Patent Document 1, a work is packed in an empty box-shaped pallet conveyed by a belt conveyor by a robot apparatus and then transferred to a belt conveyor that conveys the work in a subsequent process. The manufacturing cost is also high. In addition, since a plurality of devices are installed, the space efficiency is not good.

  The present invention has been made in view of the above-described problems of the prior art, and has an object to provide a pallet transport device that does not require pallet replacement, has a simple configuration, does not cost, and can be installed efficiently. To do.

  The present invention includes a pallet on which an object to be conveyed such as a workpiece is placed and bendable, a conveyance conveyor provided with a conveyance annular member that is placed between a pair of conveyor gears and conveys the pallet. The return conveyor for returning the pallet, which is arranged in parallel below the conveyor for conveyance and sent to the downstream side of the conveyor for conveyance, to the upstream side of the conveyor for conveyance, and the gears for the pair of conveyors are coaxial. A pair of pallet transfer members which are provided so as to be integrally rotatable and send the pallet to the opposite side between the transfer conveyor and the return conveyor, respectively, along each conveyor gear at both ends of the transfer conveyor A pair of guide members arranged to guide the transfer of the pallet between the conveyor for transfer and the return conveyor by the pallet transfer member; and A stopper provided to be locked in a predetermined position of the conveyor feeding a pallet conveying apparatus and a one or more drive motor for driving the conveyor and a return conveyor.

  Two conveyor gears are provided at each end of the conveyor, the pallet transfer member is located between the conveyor gears, and a concavo-convex portion that engages the pallet transfer member on the back surface of the pallet Is provided.

  The annular member for conveyance is a conveyance belt, and the pallet is placed on the conveyance belt for conveyance, and the pallet is slipped by the stopper and can be stopped.

The transporting annular member is a transporting chain provided with a roller on the outside, the conveyor gear is a conveyor sprocket that can mesh with the transporting chain, and the roller can transport by placing the pallet. is the possible low La stop by slipping the pallet by the stopper with it.

  According to the pallet transport device of the present invention, since a lifter device for replacing pallets is not required, the configuration is simple, the cost is not increased, the installation space is not required, and the installation can be performed efficiently.

  Hereinafter, a first embodiment of the pallet conveying device of the present invention will be described with reference to FIGS. The pallet conveying apparatus 10 of this embodiment conveys a pallet 14 on which a workpiece 12 that is a conveyance object such as a machine part is placed to the next process, and returns an empty pallet 14 to a workpiece 12 placement position. Device. As shown in FIG. 1, the pallet conveying device 10 includes a conveying conveyor 16 that conveys a workpiece 12 and a return conveyor 18 that returns an empty pallet 14.

  The conveyor 16 is provided with conveyor gears 22 at both ends in the longitudinal direction, and a conveyor belt 20 that is an endless annular member is hung on the conveyor gears 22 at both ends. The conveyor belt 20 has a concave and convex portion 20a with a constant pitch formed on the back side thereof, and can be engaged with the teeth of the conveyor gear 22. Further, a pair of conveyor gears 22 are provided at both ends of the conveyor 16 at predetermined intervals, and two conveyor belts 20 are spaced in parallel with each other at predetermined intervals. It is bridged between. A pallet transfer gear 24 is provided between each pair of conveyor gears 22 at both ends of the transfer conveyor 16 in a state of being sandwiched between the conveyor gears 22 so as to be coaxially and integrally rotatable.

  Further, outside the both ends of the conveyor 16 for conveyance, as shown in FIGS. 3 and 4, guide members 26 formed in a substantially U shape so as to cover the substantially half circumference of the conveyor gear 22 are respectively provided. It is attached. A pair of guide members 26 are provided at both ends corresponding to the two pairs of conveyor gears 22 at both ends of the conveyor 16, and the inner peripheral surface facing the conveyor gear 22 is formed in an arc shape. Each of the guide members 26 is formed so as to be divided in the vertical direction, and swings about an axis (not shown) that is parallel to the rotation axis of the conveyor gear 22 and is located outside the conveyor gear 22. And is urged in a closing direction by an elastic body (not shown).

  A plurality of pallets 14 are appropriately placed in a row on two parallel conveyor belts 20 of the conveyor 16. The pallet 14 is made of, for example, a flexible resin and is formed to be bendable. A holding portion 28 that holds the workpiece 12 is provided on the upper surface of the pallet 14. As shown in FIG. 2, the holding portion 28 includes, for example, a V-shaped receiving portion according to the workpiece 12 to be placed, and is formed in a shape that can hold the workpiece 12. Furthermore, the bottom surface of the pallet 14 is formed with an uneven portion 14 a that meshes with the pallet transfer gear 24. Further, the pallet 14 on the transporting conveyor 16 is slidably mounted on the two transporting belts 20 by a stopper 30a described later.

  In the vicinity of the workpiece take-out position on the downstream end side of the conveyor 16 for conveyance, a stopper 30a formed so as to be able to project and retract is provided with a gap slightly longer than the length of the pallet 14 in the longitudinal direction. A stopper 30b is provided at the end. Sensors 32a and 32b are attached to both sides near the stopper 30b so that the pallet 14 can be detected. On the other hand, a stopper 30c formed so as to be able to protrude and retract is provided in the vicinity of the workpiece placement position at the upstream end of the conveyor 16 and the pallet 14 is also provided in the vicinity of the upstream side of the stopper 30c of the conveyor 16. A sensor 32c is attached. Further, a sensor 32d for detecting that the pallet 14 is full is disposed on the conveyor 16 on the downstream side of the stopper 30c.

  The conveyor gear 22 at the workpiece placement position at one end constituting the conveyor 16 is provided with a drive unit coupling gear 35 coaxially with the drive gear 34 to drive the conveyor 16 and timing. It is connected by a belt 36 or a chain. In addition, a drive transmission gear 37 is provided coaxially on the conveyor gear 22 at the workpiece removal position on the other end. The drive transmission gear 37 meshes with the connection gear 38, and the connection gear 38 turns in the rotation direction so that the drive force can be transmitted to a drive gear (not shown) coaxially provided on one pulley 40 of the return conveyor 18. It has been.

  A pair of pulleys 40 are provided at both ends of the return conveyor 18, and return belts 42, which are endless annular members, are spaced apart from each other by a predetermined interval, and the holding member 28 is placed between them. It is arranged in a parallel position directly under the conveyor 16 for conveyance. At the end of the return conveyor 18 located in the vicinity of the drive motor 34, there is provided a stopper 31a formed so as to be able to project and retract with a slightly longer interval than the longitudinal length of the pallet 14. A stopper 31b is provided at the feed end. Sensors 33a and 33b for detecting the pallet 14 are attached in the vicinity of both sides of the stopper 31b. Further, a sensor 33 c for detecting the full state of the pallet 14 on the return conveyor 18 is attached to the upstream side of the return conveyor 18.

  Next, operation | movement of the pallet conveying apparatus 10 of this embodiment is demonstrated. As shown in FIG. 1, the pallet 14 is placed on the conveyor belt 20 by the conveyor 16 and moves together with the conveyor belt 20. The operation here is the same as a general pallet feeding operation.

  First, after the workpiece 12 is detected by a workpiece confirmation sensor (not shown) at the workpiece removal position of the conveyor 16 for conveyance, when it is detected that the workpiece 12 is removed and is not on the pallet 14, the stopper 30a is first protruded. In conjunction with this, the stopper 30b is returned to the retracted position. Then, one pallet 14 on the leading end side slipping on the conveying belt 20 is sent out together with the conveying belt 20, guided by the guide member 26, and sent from the conveying conveyor 16 onto the return conveyor 18. . During this time, the pallet confirmation sensor 32a is turned off with the passage of the pallet 14 from the on state, and the sensor 32b is further turned on upon detecting the top of the pallet 14 and turned off after the passage of the pallet 14.

  When the sensor 32b detects the passage of the pallet 14, the stopper 30b protrudes and the stopper 30a retracts. Then, the pallet 14 that has been locked and slipped by the stopper 30a on the conveying belt 20 is fed together with the conveying belt 20 and is locked by the stopper 30b. Thereby, the head pallet 14 is detected by the sensor 32a, and when the workpiece is detected by a workpiece confirmation sensor (not shown), the workpiece 12 is protruded. When the pallet 14 is full on the return conveyor 18, the sensor 33c is turned on and the above operation enters a standby state. After the sensor 33c is turned off, the above operation is repeated.

  Here, when the pallet 14 is positioned at the downstream end of the conveyor 16, the uneven portion 14 a on the bottom surface of the pallet 14 is moved to the pallet transfer gear 24 on the downstream side of the conveyor 16 as shown in FIGS. 2 and 4. And is drawn into the gap with the guide member 26 along the pallet transfer gear 24. At this time, as shown in FIG. 4, when the convex portion of the concavo-convex portion 14 a at the end of the pallet 14 collides with the gear crest of the pallet transfer gear 24, one of the divided guide members 26 is slightly lifted. However, the guide member 26 is urged in a direction to return to the original by an elastic body (not shown), and as the pallet 14 moves, the concavo-convex portion 14a and the teeth of the pallet transfer gear 24 naturally engage with each other. As the transfer gear 24 rotates, it moves downward along the guide member 26 and is discharged. The discharged pallet 14 is placed on a return conveyor 18 disposed below the transfer conveyor 16, and the pallet 14 moved to the return conveyor 18 is sequentially placed on the return conveyor 18 as shown in FIG. 1. It is carried downstream by the return belt 42.

  Further, in the vicinity of the workpiece placement position at the upstream end of the conveyor 16 for conveyance, when the workpiece confirmation sensor (not shown) detects that the workpiece 12 is placed on the pallet 14, the pallet 14 is full. When the sensor 32 d that detects this is off, the stopper 30 c is retracted, and the pallet 14 that has slipped on the conveying belt 20 is sent out together with the conveying belt 20. Then, after the pallet 14 is moved and the sensor 32d for detecting that the pallet 14 is full is turned on and turned off on the conveyor 16, the stopper 30c is projected. In conjunction with this, the stopper 31a is protruded and the stopper 31b is retracted. Thereby, the pallet 14 that has slipped at the tip on the return conveyor 18 is sent out, guided by the guide member 26, and sent onto the transport conveyor 16. When the sensor 33b is turned on and off as the pallet 14 passes, the stopper 31b is protruded and the stopper 31a is retracted. Further, after the sensor 33a detects the pallet 14, the above operation is repeated with the sensor 32d turned off.

  According to the pallet transfer device 10 of this embodiment, the pallet 14 can be circulated on the transfer conveyor 16 without changing the pallet 14 by a lifter device or the like. In addition, it can be installed in a space efficient manner. In addition, the uneven | corrugated | grooved part 14a formed in the bottom face of the pallet 14 should just be formed so that engagement with the pallet transfer gear 24 to engage is possible.

  Next, a second embodiment of the present invention will be described with reference to FIGS. Here, the same members as those in the above embodiment are denoted by the same reference numerals, and the description thereof is omitted. In this embodiment, the pallet conveying device 50 is provided with conveyor sprockets 46 each being a gear for a conveyor in which a conveying chain 44 meshes with both ends of the conveying conveyor 16. A pallet transfer sprocket 48, which is a pallet transfer member, is formed coaxially with the conveyor sprocket 46 and sandwiched between two conveyor sprockets 46. Further, guide members 26 are respectively attached so as to cover the conveyor sprocket 46. The transport chain 44 is provided with a roller 52 made of a resin or the like that is formed so as to be rotatable every other link of the transport chain 44 toward the outside. On the roller 52, a plurality of pallets 54 are appropriately placed in a row.

  The pallet 54 is formed, for example, so that it can be bent by connecting rectangular metal plates with a link material, and a plurality of engagement protrusions 54 a that are concavo-convex portions that can engage with the pallet transfer sprocket 48 are provided at the center of the bottom surface of the pallet 54. It has been. A holding portion 28 having a V-shaped receiving portion for holding the workpiece 12 is provided on the top surface of the pallet 54.

  Next, the operation of this embodiment will be described. As in the first embodiment, the pallet 54 on the transport conveyor 16 is placed on a roller 52 provided on the transport chain 44, and the pallet 54 moves in one direction by the transport conveyor 16. When the pallet 54 is locked by a stopper (not shown), the pallet 54 is stopped at the end of the transfer conveyor 16 against the movement of the transfer chain 44 by the rotation of the roller 52. When the stopper is lowered, the pallet 54 on which the workpiece 12 is placed is moved in the downstream direction by the conveying chain 44 while the pallet 54 is placed on the roller 52. By repeating this operation, the workpieces 12 are sequentially placed on the pallet 54 and moved.

  Further, when the pallet 54 on which the workpiece 12 is placed reaches the vicinity of the downstream end portion of the transfer conveyor 16, the pallet 54 locked by a stopper (not shown) is not shown, as in the first embodiment. The work 12 is moved to the next process by the apparatus. At this time, the pallet 54 locked by the stopper is stopped against the movement of the transport chain 44 by the rotation of the roller 52. Subsequently, the pallet 54 that has become empty moves to the downstream end of the conveyor 16 by the transport chain 44 when the stopper is lowered. When the pallet 54 is positioned at the end of the transfer conveyor 16, the engagement protrusion 54 a on the bottom surface of the pallet 54 meshes with the pallet transfer sprocket 48 at the downstream end as shown in FIG. Then, it is drawn into the gap with the guide member 26. The pallet 54 makes a half turn along the guide member 26 as the pallet transfer sprocket 48 rotates, moves downward, and is discharged from the guide member 26. The discharged pallet 54 is placed on the return conveyor 18 disposed below the transfer conveyor 16. Then, the pallet 54 moved to the return conveyor 18 sequentially moves to the downstream side of the return conveyor 18. On the downstream side of the return conveyor 18 and the upstream side of the transfer conveyor 16, as shown in FIG. 6, the engagement protrusion 54a on the bottom surface of the pallet 54 meshes with the pallet transfer sprocket 48 at the upstream end, and the pallet Along with the transfer sprocket 48, it is drawn into the gap with the guide member 26 on the upstream side, and is returned again onto the conveyor 16 for transfer, as in the first embodiment.

  According to the pallet conveying device 50 of this embodiment, since the pallet 54 circulates on the conveyor 16 without the need to replace the pallet 54 by a lifter device or the like, the configuration is simple and production costs are not increased. It can be installed in a space efficient manner. In addition, the conveyance chain 44 can reliably convey the pitch without the belt stretch, and the metal pallet 54 can have high durability.

  Next, a third embodiment of the present invention will be described with reference to FIGS. Here, the same members as those in the above embodiment are denoted by the same reference numerals, and the description thereof is omitted. In this embodiment, the pallet conveyor device 56 is provided with conveyor sprockets 46 that are conveyor gears engaged with the conveyor chain 44 at both ends of the conveyor 16. A pallet transfer gear 24 that is a pallet transfer member is provided coaxially with the conveyor sprocket 46 and sandwiched between the two conveyor sprockets 46. Further, guide members 26 are respectively attached so as to cover the conveyor sprocket 46. The transport chain 44 is provided with a roller 52 made of a resin or the like that is formed so as to be rotatable every other link of the transport chain 44 toward the outside. On the roller 52, a plurality of pallets 14 similar to those in the first embodiment are appropriately placed in a row.

  As in the first embodiment, the operation of this embodiment is such that the pallet 14 on the conveyor 16 is placed on a roller 52 provided on the conveyor chain 44 and is moved in one direction by the conveyor 16. The pallet 14 moves. When the pallet 14 is locked by a stopper (not shown), the pallet 14 stops at the end of the transport conveyor 16 with respect to the movement of the transport chain 44 by the rotation of the roller 52. When the stopper is lowered, the pallet 14 on which the workpiece 12 is placed is moved in the downstream direction by the transport chain 44 while the pallet 14 is placed on the roller 52. By repeating this operation, the workpieces 12 are sequentially placed on the pallet 54 and moved.

  According to this embodiment, in addition to the effects of the above-described embodiment, the flexible pallet 14 can be used, and the slip of the pallet 14 is smooth by the roller 52, and even when the transport chain 44 breaks down, the chain It can be exchanged by each frame, and the maintenance cost is low.

  Next, a fourth embodiment of the present invention will be described with reference to FIGS. Here, the same members as those in the above embodiment are denoted by the same reference numerals, and the description thereof is omitted. In this embodiment, a modified example of a pallet used for a transfer conveyor of a pallet transfer apparatus is shown. The pallet 64 of this embodiment is composed of a strip-shaped metal plate or resin plate on the pallet support portion 62 using the flexible pallet of the first embodiment, and a workpiece support plate 66 longer than the width of the pallet support portion 62. Are fixed in parallel. Each work support plate 66 is fixed to the pallet support part 62 in parallel in a direction perpendicular to the pallet moving direction.

  Thereby, the large and wide workpiece can be safely conveyed by the hard and long workpiece support plate 66. Moreover, as shown in FIG. 11, at the end of the conveying conveyor end 16, it is easily bent and placed on the return conveyor.

  According to this embodiment, in addition to the effects of the above embodiment, a flexible pallet 64 on which a large workpiece can be placed can be easily formed.

  The pallet conveying device of the present invention is not limited to the above embodiment, and the shape of the pallet transfer member can be set as appropriate, such as a gear, a sprocket, and other shapes formed with engagement protrusions. In addition, the shape of the work holding portion provided on the pallet can be appropriately set according to the work to be used. The size of the pallet, the size of the conveyor for conveyance, and the size of the conveyor for return can be appropriately set according to the size of the workpiece. Furthermore, the shape and material of each member can be appropriately changed.

It is a schematic side view which shows the pallet conveying apparatus of 1st embodiment of this invention. It is a longitudinal cross-sectional view which shows the one end part of the pallet conveying apparatus of 1st embodiment of this invention. It is a partially broken side view which shows the conveyance upstream upstream edge part of the pallet conveying apparatus of 1st embodiment of this invention. It is a partially broken side view which shows the conveyance conveyor downstream end part of the pallet conveying apparatus of 1st embodiment of this invention. It is a longitudinal cross-sectional view which shows the one end part of the pallet conveying apparatus of 2nd embodiment of this invention. It is a partially broken side view which shows the conveyance upstream upstream edge part of the pallet conveying apparatus of 2nd embodiment of this invention. It is a longitudinal cross-sectional view which shows the one end part of the pallet conveying apparatus of 3rd embodiment of this invention. It is a partially broken side view which shows the conveyor conveyor upstream end part of the pallet conveying apparatus of 3rd embodiment of this invention. It is the top view (a) and side view (b) which show the pallet used for the pallet conveying apparatus of 4th embodiment of this invention. It is a front view which shows the pallet used for the pallet conveying apparatus of 4th embodiment of this invention. It is a side view which shows the use condition of the pallet used for the pallet conveying apparatus of 4th embodiment of this invention.

Explanation of symbols

10, 50, 56 Pallet transport device 12 Work piece 14, 54, 64 Pallet 16 Transport conveyor 18 Return conveyor 20 Transport belt 22 Conveyor gear 24 Pallet transfer gear 26 Guide members 30a, 30b, 30c, 31a, 31b Stopper 32a 32b, 32c, 32d, 33a, 33b, 33c Sensor 34 Driving motor 44 Conveying chain 46 Conveying sprocket 48 Pallet transfer sprocket 52 Roller

Claims (3)

A pallet on which the object to be conveyed can be placed, a pallet that can be bent, a conveying conveyor that is provided between a pair of conveyor gears and that conveys the pallet placed on the conveying conveyor, and below the conveying conveyor A return conveyor for returning the pallet arranged in parallel and sent to the downstream side of the conveyor to the upstream side of the conveyor, and the pair of conveyor gears are provided so as to be integrally rotatable with each other. A pair of pallet transfer members that send the pallet to the opposite side between the transfer conveyor and the return conveyor, and each pallet transfer member disposed along each conveyor gear at both ends of the transfer conveyor. A pair of guide members for guiding transfer of the pallet between the conveyor for conveyance and the conveyor for return; and a predetermined position of the conveyor for conveying the pallet. A stopper provided to be engaged with, and a one or more drive motor for driving the conveyor and a return conveyor, said conveyor gear 2 each provided at both ends of the conveyer, The pallet transport member is located between the conveyor gears, and a concavo-convex portion engaging with the pallet transport member is provided on the back surface of the pallet.   The said annular member for conveyance is a belt for conveyance, The said pallet is mounted and conveyed on the said belt for conveyance, The said pallet can be slipped and stopped by the said stopper. Pallet transport device. The transporting annular member is a transporting chain provided with a roller on the outside, the conveyor gear is a conveyor sprocket that can mesh with the transporting chain, and the roller can transport by placing the pallet. The pallet transporting device according to claim 1 , wherein the pallet transporting device is a roller that can be stopped by slipping the pallet with the stopper.

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