JPH1111660A - Conveying mechanism and working system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable send a pallet from an upstream processing position at early stages while surely placing only one work pallet at a downstream processing position, in a conveying mechanism which feeds the pallets using a free-flow conveyor, stops the pallets using stoppers provided at a plurality of processing positions and processes work on the pallets. SOLUTION: This conveying mechanism is provided with an escape claw 7 which moves from a fixed position P downstream from a stopper 4a at an upstream processing position to the position of a stopper 4b at a downstream processing position while closed, and which returns to its original position while open. At the completion of a process at the downstream position or after the finish of a process at a position upstream from it, the stopper 4a at the upstream position opens and sends a pallet 3, and, with the pallet 3 either stopped by the escape claw 7 at the fixed position P or flowing toward the claw 7, the stopper 4b at the downstream position is opened at the completion of the process at the downstream position 5, and at the same time the escape claw 7 is moved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pallet transfer mechanism for feeding a work pallet (hereinafter referred to as a pallet) by a free flow conveyor, stopping the pallet at a plurality of processing positions, and processing the work thereon. If only one pallet has to be supplied to the processing position of that position, i.e. the processing at that position has ended and the next pallet has to flow before the pallet has been discharged downstream, The present invention relates to a transport mechanism in which a waiting time is shortened as much as possible to improve a transport speed.

[0002]

2. Description of the Related Art Conventionally, this type of transport line is composed of a conveyor belt 1a which moves at a predetermined speed and guide rails 1b arranged on both sides of the conveyor so as not to spill as shown in a plan view conceptually shown in FIG. A stopper 4a for stopping the pallet 3 is provided at the processing position 2 on the upstream side of the conveyor line 1 so as to be openable and closable. The stopper 4a is closed to stop the pallet 3 so that a predetermined work (not shown) is mounted on the work (not shown). Perform processing. Another processing position 5 is also provided on the downstream side and has a similar stopper 4b.

Here, if the processing at the downstream processing position 5 requires only one pallet 3,
That is, if it is not good that the next pallet flows during the processing, when the processing at the downstream processing position 5 is completed, the stopper 4b is opened and the pallet 3 flows, but the stopper 4a of the upstream processing position 2 immediately Wait for a while without opening, and after confirming that the pallet 3 has been completely discharged from the downstream processing position 5 by, for example, the reflection type sensor 6 disposed on the downstream side, the downstream stopper 4b is closed and the upstream stopper 4a is closed. Open the next palette 3
Is flowing. And, the stopper 4a on the upstream side
A similar sensor 6 is arranged on the downstream side, and after confirming that the pallet 3 has passed, the stopper 4a on the upstream side is closed and the arrival of the next pallet 3 is awaited.

[0004] In the free flow method, the pallet 3 does not always flow at the speed of the conveyor line 1, but tends to stop at a very low speed due to, for example, friction with the guide rail 1b. If the stopper is closed before it is completely discharged, it will collide with the pallet 3 or the work (not shown), causing trouble. This is because it becomes a series and this is also a trouble.

[0005]

However, according to the above-described transport mechanism, after confirming that the pallets have been completely discharged, the next pallet flows from the upstream processing position. It takes time to process the workpiece, and the processing speed cannot be increased. Further, even if the processing at the upstream processing position is completed, the pallet is not flown until the processing position at the downstream side becomes empty, so that the processing of the next work is not started. .

[0006]

In order to solve the above-mentioned problems, according to the present invention, a pallet is fed by a free flow conveyor, and the pallets are sequentially stopped by stoppers provided at a plurality of processing positions, and the work on the pallet is processed. In the transport mechanism, the pallet waits at a fixed position between the stopper position of the downstream processing position and the stopper position of the upstream processing position, moves from there to the stopper position of the downstream processing position in a state where the pallet is caught, and moves the pallet. The present invention provides a transport mechanism characterized by providing an escape claw that returns to a state where it does not hinder the transfer. Further, in a work system in which a work pallet on which a work is mounted is placed on a free flow conveyor and conveyed, and the stop processing is performed at a plurality of predetermined positions by opening and closing a stopper mechanism, the processing on the upstream side is completed until the processing on the downstream position is completed. A work system comprising an escape mechanism for stopping the flow of the work pallet and forcibly discharging the work pallet on the downstream side in accordance with the completion of the processing at the downstream position. According to the above configuration, for example, both the processing at the upstream processing position and the processing at the downstream processing position are completed, and the stopper at the upstream processing position and the stopper at the downstream processing position are opened and the escape claw is moved, so that the downstream processing is performed. Even if the flow of the pallet in the side processing position is bad, the escape claw is pushed out surely 2
No individual pallets remain in the downstream processing position. Since the next pallet starts to flow before the previous pallet is completely discharged from the downstream processing position, the time required for transport is reduced by that amount. If the processing at the upstream processing position ends earlier than the processing at the downstream processing position, the stopper is opened after the processing at the upstream processing position ends, and then the processing at the downstream processing position. If the stopper is opened and the escape claw is moved after the completion of the operation, the next pallet reaches the downstream side more quickly.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Various known combinations of conveyors and pallets in the apparatus of the present invention can be used. If the pallet or the work to be placed on the pallet is light, the conveyor may be a belt conveyor with a smooth surface, and the pallet may simply have a smooth back surface. In the case of a heavy work, it is preferable that the pallet be provided with rollers and casters on the back surface.
Conversely, the rollers arranged endlessly close to the conveyor may move, and the pallet may simply have a flat back surface. The pallet on which the work is placed flows on the conveyor together with the conveyor, but when stopped by a stopper, the pallet slips or the rollers and casters rotate to reduce friction with the conveyor.

[0008] The stopper may be one that moves back and forth in a direction parallel to the surface of the conveyor (in the horizontal direction) and at right angles to the traveling direction, or one that moves back and forth at right angles to the conveyor surface (in the vertical direction).

The escape claw is moved to a position where it interferes with the pallet flow by a movement similar to that of the stopper, or retracted to a position where it does not interfere. Furthermore, it can be moved in the traveling direction of the conveyor. The means of movement is an air cylinder,
A known method such as ball screw feed can be used.

[0010]

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a plan view conceptually showing the transport mechanism of the present invention. The same parts as in the conventional example of FIG. A stopper 4a for stopping the pallet 3 is provided at a processing position 2 on the upstream side of the conveyor line 1 comprising a conveyor belt 1a moving at a predetermined speed and guide rails 1b arranged on both sides so as not to spill, similarly to the conventional apparatus. Is provided so as to be openable and closable, and shows a state in which the pallet 3 is closed and a predetermined process is performed on a work (not shown) placed thereon. In the processing position 5 on the downstream side, the stopper 4b is closed and the pallet 3 is stopped to perform a predetermined process on a workpiece (not shown) thereon. The processing at the processing position 5 on the downstream side is only one for the pallet 3.
It must be arranged individually. That is, if the next pallet flows during the processing, the processing content is inconvenient.

The upstream stopper 4a and the downstream stopper 4
The escape claw 7 closes and stops at a predetermined position P between the pallet 3 and the pallet 3. The escape claw 7 is attached to the tip of a shaft 7a connected to a cylinder (not shown), and is movable along the conveyor belt 1a by the movement of the shaft 7. The pallet 3 is opened to face upward by the rotation of the shaft 7a so as not to interfere with the flow of the pallet 3, or is closed in a horizontal direction to obstruct the flow of the pallet 3, or can be freely opened and closed. is there.

Next, a more detailed configuration will be described with an explanation of the operation of the transport mechanism. The operation after the state where the pallet 3 is stopped at both the upstream position 2 and the downstream position 5 as shown in FIG. (1) When the processing on the upstream side 2 is completed and the processing on the downstream side is also completed, both the upstream stopper 4a and the downstream stopper 4b are opened, and both pallets 3 begin to flow. At the same time, the escape claw 7 moves downstream while being closed. The moving speed is equal to or slightly lower than the speed of the conveyor belt 1a. (2) When the sensor 6 confirms that the upstream pallet 3 has completely passed through the upstream stopper 4a, the upstream stopper 4a closes and waits for the arrival of the next pallet 3. (3) When the escape claw 7 reaches the position of the stopper 4b on the downstream side and stops, the pallet 3 which was at the downstream position 5 has normally flowed further downstream and does not touch the escape claw. The escape claw pushes out surely to the downstream side. The pallet 3 at the upstream position 2 reached after catching up and moving along with the escape claw or stopping after the escape claw may be stopped by the escape claw 7 in some cases. (4) In this state, the downstream side stopper 4b closes and the escape claw 7 opens. When it is confirmed that the pallet 3 is set at each of the upstream position 2 and the downstream position 5 by a sensor (not shown), the processing is started at each of them. (5) In the meantime, the escape claw 7 returns to the predetermined position P without interfering with the pallet 3 in the open state, closes again, and returns to the initial state shown in FIG. Thereafter, the operations of (1) to (5) are repeated to carry and carry.

According to this embodiment, before the downstream pallet 3 is discharged, the upstream pallet 3 starts to flow, so that the next pallet 3 is arranged at the downstream position 5 earlier by that amount, and is conveyed. Speed increases.

In the above-described embodiment, the processing of both the upstream position 2 and the downstream position 5 is completed and both pallets 3 are started to flow at the same time. If the processing at the downstream position is always earlier or sometimes earlier than the end of the processing at the downstream position, the pallet is allowed to flow to the escape claw as soon as the processing at the upstream side is completed, so that the transport time can be further reduced.
In the case of the next embodiment, the basic configuration is the same as that of the above embodiment, and only the control program is different. The operation after the state where the pallet 3 stops at both the upstream position 2 and the downstream position 5 as shown in FIG. (1) When the processing at the upstream position 2 happens to be completed quickly, the upstream stopper 4a is opened and the pallet 3 starts to flow regardless of the state of the processing on the downstream side. (2) When the processing at the downstream position 5 is completed while the pallet 3 on the upstream side is stopped by the escape claw 7 or flows toward the escape claw 7, the stopper 4b on the downstream side is opened and the pallet 3 starts to flow. At the same time, the escape claw 7 moves downstream while being closed. The moving speed is the same as or slightly slower than the speed of the conveyor belt 1a. (3) When the sensor 6 confirms that the upstream pallet 3 has completely passed through the upstream stopper 4a, the upstream stopper 4a closes and waits for the arrival of the next pallet 3. (4) When the escape claw 7 comes to the position of the stopper 4b on the downstream side and stops, the pallet 3 at the downstream position 5 has normally flowed further downstream and does not touch the escape claw. The escape claw pushes out surely to the downstream side. The pallet 3 which has moved at the same time as the escape claw or reached in the upstream position 2 after the escape claw was stopped is stopped by the escape claw 7. (5) In this state, the downstream side stopper 4b is closed and the escape claw 7 is opened. When it is confirmed that the pallet 3 is set at each of the upstream position 2 and the downstream position 5 by a sensor (not shown), the processing is started at each of them. (6) During that time, the escape claw 7 returns to the predetermined position P without interfering with the pallet 3 in the open state, closes again, and returns to the initial state shown in FIG. Thereafter, the operations (1) to (5) are repeated to carry out the transfer and the processing. (1 ') If the processing at the downstream position 5 happens to be completed quickly, the processing at the upstream position 2 is continued. After the completion, the downstream stopper 4b and the upstream stopper 4a are simultaneously opened and the movement of the escape claw 7 is started immediately. Thereafter, the operation after the above (3) is performed.

According to this embodiment, the upstream position 2
Is faster than the processing at the downstream position 5, the transport time is further reduced.

[0016]

As described above, according to the present invention, the pallet is fed by the free flow conveyor, the pallet is stopped at a plurality of processing positions, and the time required for carrying the workpiece on the pallet is shortened.

[Brief description of the drawings]

FIG. 1 is a plan view of an embodiment of the present invention.

FIG. 2 is a plan view of a conventional transport mechanism.

[Explanation of symbols]

 1 Conveyor line 1a Conveyor belt 3 Work pallet (pallet) 2,5 Processing position 4a, 4b Stopper 7 Escape claw P Fixed position

Claims (6)

[Claims] In a transfer mechanism for feeding a work pallet by a free flow conveyor, sequentially stopping the work pallets by stoppers provided at a plurality of processing positions, and processing the work on the work pallet, a stopper position at a downstream processing position is determined. Stand by at a fixed position between the stopper position of the upstream processing position, move the work pallet from there to the stopper position of the downstream processing position in a state where it is hooked, and return the escape claw that returns even in a state where the work pallet flow is not obstructed. A transport mechanism characterized by being provided. 2. The processing at the upstream processing position and the processing at the downstream processing position are both completed, the stopper at the upstream processing position and the stopper at the downstream processing position are opened, and the escape claw is moved. 1 transport mechanism. 3. When the processing at the upstream processing position is completed earlier than the processing at the downstream processing position, the stopper is opened after the processing at the upstream processing position is completed. 2. The transport mechanism according to claim 1, wherein the stopper is opened and the escape claw is moved after the end of the processing. 4. In a work system in which a work pallet on which a work is mounted is placed on a free flow conveyor and conveyed, and a stop process is performed at a plurality of predetermined positions by opening and closing operations of a stopper mechanism, the work process at a downstream position is completed. A work system comprising an escape mechanism for stopping the flow of a work pallet on the upstream side and forcibly discharging the work pallet on the downstream side in accordance with completion of the processing at the downstream position. 5. The work system according to claim 4, wherein said escape mechanism moves an escape claw at a speed lower than a feed speed of said free flow conveyor. 6. The work system according to claim 4, wherein the opening / closing operation of the stopper mechanism is timing-controlled in relation to the operation of the escape mechanism.