JPH046579B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a stopper device for a pallet conveyor that circulates a plurality of pallets in a free cycle and stops them at a predetermined work station.

Prior Art Conventionally, this type of pallet conveyor 1 has a main transfer path 31 having an endless chain 3 that circulates in a fixed direction on a horizontally arranged conveyor frame 2, as shown in FIGS. 7 to 9; A reverse transfer path 32 having an endless chain 3a that circulates in a direction opposite to the moving direction of the endless chain 3, and a main transfer path 3.
A first transfer device 33 that transfers the pallet 10 from the reverse transfer path 32 to the main transfer path 3;
1 and a second transfer device 34 for transferring the pallets 10 to the pallet 1. Further, work stations (not shown) are arranged on the pallet conveyor 1 at predetermined intervals, and a work unit (not shown) is attached to each work station. Furthermore, an endless chain 3 is disposed in the pallet conveyor 1 so as to circulate within the conveyor frame 2, and a sprocket 35 is rotatably disposed on the pallet 10 so as to mesh with the endless chain 3. ing. This sprocket 35 is connected to a clutch mechanism 38,
This clutch mechanism 38 transmits the traction force of the endless chain 3 to the pallet 10 when the sprocket 35 stops rotating relative to the pallet 10, and also transmits the traction force of the endless chain 3 to the pallet 10 when it rotates in that position relative to the pallet 10 due to the circular movement of the endless chain 3. Traction power is pallet 10
The pallet 10 is configured to stop at that position without being transmitted. Further, one cam follower 11 is disposed on the pallet 10 so as to protrude upward, and a stopper 36 having a U-shaped groove that can be engaged with the cam follower 11 is disposed on the movement path of the cam follower 11. This stopper 36 is configured so that when the pallet 10 is separated from the cam follower 11, it is once rotated upward and the pallet 10 is moved.

Problems to be Solved by the Invention In the above-mentioned pallet conveyor 1, the pallet 10 is positioned only in the forward direction by the stopper 36, and in order to improve the stopping accuracy of the pallet 10, the pallet 10 is moved straight along the conveyor frame 2. It is configured to constantly move along a guide shaft 37 arranged on a line. Therefore, it becomes difficult to remove the pallet 10 from the conveyor frame 2, resulting in drawbacks such as the inability to easily replace the pallet 10. Furthermore, since the guide shaft 37 is inserted through the pallet 10, each of the pallet 10 and the guide shaft 37 must be machined with high precision, which not only increases the cost of the device but also makes it difficult to align the guide shaft 37 in parallel. The disadvantage is that the work is extremely troublesome and requires skill. Furthermore, in this pallet conveyor 1, when the pallet 10 is stopped at a predetermined position by the stopper 36, a clutch mechanism 38 is required to cut off the traction force of the endless chain 3, and this clutch mechanism 38 is extremely complicated and has a large number of parts. In many cases, the assembly work is complicated, resulting in disadvantages such as an increase in the cost of the pallet conveyor 1.

Means for Solving the Problems The present invention aims to eliminate the above-mentioned drawbacks.
An endless chain is disposed so as to be able to circulate freely along the conveyor frame, and the conveyor frame is constructed so that pallets can be moved in a predetermined direction. Friction plates are arranged on the sides of the pallet; one friction plate is fixed to the pallet, and the other friction plate is always biased in the direction of protrusion and is attached so that it can freely move back and forth, and is used to pull the endless chain. The force is transmitted to the pallet by the friction force of the friction plate. Further, protrusions are arranged at each of the forward end and the backward end of the bottom of the pallet.

On the other hand, a stopper plate is attached to the conveyor frame, and a guide block is disposed on the stopper plate, which corresponds to each of the protrusions and has a guide surface for guiding the protrusions and a reference surface for positioning the protrusions. There is. Stoppers are arranged along each of these guide blocks, and one of the stoppers is configured to be movable on the travel path of one of the protrusions. Further, the other stopper is configured to be able to press another protrusion in the forward direction.

Furthermore, the reference plane of the guide block is located on one side of the corresponding protrusion, on the movement path of the protrusion, and is biased in a direction that intersects the direction of travel and always projects the protrusion. It is located at a position where the friction plate is moved in the direction of pressing.

Operation In the above pallet conveyor, when the pallet reaches a predetermined position, one protrusion of the pallet is guided by the guide block and stopped by the corresponding stopper. At the same time, the other protrusion is guided by and lies along the other guide block. The other stop then presses the protrusion in its forward direction, stopping the pallet in that position. At this time, since each of the protrusions is moving along the guide block, the protrusions move in a direction that intersects with the direction in which they move.
Therefore, the pallet separates from one of the endless chains, the frictional force of the friction plate is cut off, and the endless chain can move without any problem even if the pallet is stopped. At this time, the frictional force between the friction plate, which is biased in the protruding direction, and the attachment increases, and while the pallet is stopped, this friction plate wears out faster than the friction plate on the stationary side, but
Since the friction plate is always urged in the protruding direction, wear of the friction plate does not have any adverse effects.

Embodiments Hereinafter, embodiments will be described with reference to the drawings. In FIGS. 1 to 5, reference numeral 1 denotes a pallet conveyor, which has an endless chain 3 that circulates in a fixed direction on a horizontally arranged conveyor frame 2. An endless chain 3 is attached to the conveyor frame 2.
A chain guide 4 is disposed in the extending direction of the endless chain 3, and the chain guide 4 is made of a wear-resistant material having a low coefficient of friction with respect to the endless chain 3.

Further, the endless chain 3 is guided from below by a chain receiver 5, and the endless chain 3 is configured to move straight. A substantially rectangular plate-shaped attachment 6 is attached to the endless chain 3 and also serves as a connecting plate, and this attachment 6 is arranged so as not to come into contact with an adjacent one. Furthermore, this attachment 6 is located between the chain guide 4 and friction plates 7, 7a, which will be described later, and is configured to be held between them.

On the other hand, a horizontally extending rail plate 8 is disposed on the conveyor frame 2, and rollers 9, which will be described later, are configured to roll along the rail plate 8. Further, a plurality of pallets 10 are movably mounted on the conveyor frame 2, and four rollers 9 are rotatably fixed to the lower part of the pallets 10. Projections consisting of cam followers 11 and 11a are arranged at the forward and backward ends of the pallet 10 in point symmetry with respect to the center of the pallet 10, that is, at opposite positions at a predetermined distance from the center. The cam followers 11, 11a are stopped by a stopper device 12 (described later) disposed at a work station (not shown), and the pallet 10 is stopped.
is configured so that it stays there.

Two friction plates 7, 7a are arranged along the endless chain 3 on the side of the pallet 10, and these friction plates 7, 7a are made of anti-wear material with a high friction coefficient for the attachment 6. It is formed of. The friction plate 7a is fixed to the pallet 10, and the other friction plate 7 is always urged by a spring 13 so as to be freely retractable.

On the other hand, a stopper device 12 is attached to the conveyor frame 2. This stopper device 1
2 has a stopper plate 14, and this stopper plate 14
cam follower 1 at the forward end of the pallet 10.
A front guide block 15 and a rear guide block 16 are fixed to guide the cam follower 11a and the rearward end cam follower 11a, respectively. The rear guide block 16 has a guide surface for guiding the cam follower 11a on the side opposite to the center of the stopper plate 14, and this guide surface forms a reference surface for positioning the cam follower 11a. Also, after this, guide block 1
The reference plane 6 is located on the movement path of the cam follower 11a, and the cam follower 11a is moved in a direction crossing the direction of movement thereof, and the friction plate 7a on the fixed side is moved to the attachment 6 of the endless chain 3.
It is configured to separate from the A rear stopper 17 is attached to the rear guide block 16 and is rotatable along the guide surface, and a shock absorber 19 is integrally fixed to the rear stopper 17. After this, a small cylinder 20 fixed to the stopper plate 14 is attached to the stopper 17.
A rod 20a is connected thereto, and the operation of the small cylinder 20 causes the stopper portion 18 of the rear stopper 17 to reach a position where it engages with the cam follower 11a of the pallet 10.

On the other hand, the front guide block 15 has a guide surface on the center side of the stopper plate 14, and this guide surface is configured to guide the cam follower 11, and this guide surface also serves as a reference surface for positioning the cam follower 11. It is configured to do.
Further, the reference surface of the front guide block 15 is located on the moving path of the cam follower 11, and the cam follower 11 is moved in a direction intersecting with the direction of movement of the cam follower 11, and similarly to the rear guide block 16, the friction plate 7a on the fixed side is moved. It is configured to be detached from the attachment 6.

A front stopper 21 is attached to the front guide block 15.
is arranged so as to push the cam follower 11 forward. The front stopper 21 is rotatably connected to a rotary lever 22 attached to the stopper plate 14 via a first fixture 23a. Further, a rod 24a of a cylinder 24 rotatably attached to the stopper plate 14 via a second fixture 23b is fixed to the front stopper 21, and when the rod 24a is actuated, the front stopper 21 moves forward and the cam follower 1 is moved forward.
It is configured to reach the travel path of No. 1.

Further, the front stopper 21 and the rear stopper 17 each have an inclined surface that is inclined with respect to the advancing direction of the cam followers 11 and 11a, and this inclined surface forms an acute angle with the front guide block 15 and the rear guide block 16, Cam follower 11, 11a
is configured to move toward the reference surface side.

In the above pallet conveyor, when the endless chain 3 circulates along the conveyor frame 2, the attachment 6 also circulates together. Since friction plates 7, 7a are pressed against this attachment 6, when the attachment 6 slides along the chain guide 4, the friction plates 7, 7a and the pallet 10 are moved as the attachment 6 slides along the chain guide 4.
move together.

When stopping the pallet 10 at a predetermined working position, the small cylinder 20 is operated to position the rear stopper 18 and the shock absorber 19 on the path of movement of the cam follower 11a. Thereafter, when the pallet 10 reaches the predetermined working position, the
As shown in FIG. 2, the cam follower 11a at the rearward end comes into contact with the shock absorber 19, and then comes into contact with the stopper portion 18 of the rear stopper 17 and stops. When the pallet 10 stops at the approximate position, the cylinder 24
is activated to move the front stopper 21 forward. Therefore, as shown in FIG. 6b, the front stopper 21 contacts the cam follower 11 at the forward end and brings it into contact with the front guide block 15, and the rear stopper 17 brings the cam follower 11a at the backward end into contact with the rear guide block 16. Palette 1
0 is positioned at a predetermined position.

At this time, the front guide block 15 and the rear guide block 16 move the cam followers 11 and 11a in a direction perpendicular to the direction of movement of the cam followers 11 and 11a, respectively, as shown in FIG. moves slightly until it separates from attachment 6. On the other hand, the elastically biased friction plate 7 is in contact with the attachment 6, but since this friction plate 7 can be retracted into the pallet 10, when the attachment 6 moves and its frictional force increases, the friction plate 7 7
can be moved back, and the attachment 6 is attached to the friction plate 7.
Move by sliding along.

Effects of the Invention As explained above, the present invention provides protrusions at each of the forward and backward ends of a pallet, guides these to a guide block, and locks one of the protrusions with a corresponding stopper. The other protrusion is configured to be pressed in the forward direction by another stopper, and the guide block is configured to move the protrusion in a direction intersecting the respective advancing directions to separate the friction plate of the pallet from the endless chain. Because of this structure, the pallet can be stopped at a predetermined position regardless of the conveyor frame, eliminating the need for guide shafts and other parts that require troublesome installation work, and cutting off the traction force of the endless chain. Mechanism is no longer required,
There are advantages such as being able to provide a pallet conveyor that is easy to assemble and is inexpensive. Further, the present invention is configured such that when positioning the pallet, the friction plate fixed to the pallet is separated from the endless chain, and the friction plate, which is biased in the projecting direction, is moved in the direction of pressing against the attachment. Therefore, the frictional force between the friction plate, which is biased in the protruding direction, and the attachment increases, and the friction plate wears out while the pallet is stopped, but this friction plate is always biased in the protruding direction. Therefore, not only does the wear of this friction plate not have any negative effects, but also the wear of the friction plate on the stationary side can be completely prevented, and the distance from the conveyor frame when the pallet moves is maintained constant. When installing the stopper device on the conveyor frame, it can be installed without considering the wear of this friction plate, resulting in a simple installation process.Furthermore, the stopper device can be installed on the conveyor frame without worrying about the wear of the friction plate, and it is always constant even when detecting a moving pallet from the conveyor frame side. It has the advantage that detection can be performed at the position of , and accurate position detection is possible.

[Brief explanation of drawings]

FIG. 1 is a plan view of the main parts of the present invention, FIG. 2 is a cross-sectional view of the main parts of the pallet conveyor according to the present invention, FIG. 4 is a partial view of an endless chain according to the present invention, FIG. 5 is a front view of main parts of a stopper device according to the present invention, FIG. 6 is an explanatory diagram of the operation of the present invention, and FIG. 7 is an overall front view of a conventional example. , FIG. 8 is an enlarged plan view of the main part of FIG. 7, and FIG. 9 is a sectional view of the main part along the line BB in FIG. 1... Pallet conveyor, 2... Conveyor frame, 3... Endless chain, 4... Chain guide, 5... Chain receiver, 6... Attachment, 7, 7a... Friction plate, 8... Rail plate, 9...Roller, 10...Palette, 11,1
1a... Cam follower, 12... Stopper device,
13... Spring, 14... Stopper plate, 15... Front guide block, 16... Rear guide block, 1
7... Rear stopper, 18... Stopper part, 19...
...Shock absorber, 20...Small cylinder, 2
0a...small rod, 21...front stopper, 22...
... Rotating lever, 23a... First fixture, 23b...
...Second fitting, 24...Cylinder, 24a...Rod, 31...Main transfer path, 32...Reverse transfer path, 3
3...First transfer device, 34...Second transfer device, 3
5... Sprocket, 36... Stopper, 37...
...Guide shaft, 38...Clutch mechanism.

Claims (1)

[Claims] 1 An endless chain 3 along the conveyor frame 2
A pallet 10 is disposed on the conveyor frame 2 so as to be movable in a predetermined direction, and friction plates 7, 7a are disposed on the sides of the pallet 10 along the endless chain 3.
and place one friction plate 7 on pallet 10.
The structure is such that the traction force of the endless chain 3 is transmitted to the pallet 10 by the frictional force of the friction plates 7, 7a. On the other hand, in a pallet conveyor in which protrusions 11, 11a are arranged at the forward and backward ends of the bottom of the pallet 10, a stopper plate 14 is attached to the conveyor frame 2, and the protrusions 11, 11 are attached to the stopper plate 14.
Guide blocks 15 and 16 each having a guide surface for guiding the guide block and a reference surface for positioning the guide blocks 15 and 16 are arranged corresponding to each of the guide blocks 15 and 16, and stoppers 17 and 21 are installed along these guide blocks 15 and 16, respectively.
, and one stopper 17 is connected to the small cylinder 20.
The stopper 21 of the other side is connected to the rod 24a of the cylinder 24 attached to the stopper plate 14 side, and the stopper 21 moves the other protrusion 11a to the moving path. The guide blocks 15 and 16 are configured to be able to be pressed in the forward direction, and the reference surfaces of the guide blocks 15 and 16 are positioned on one side of the corresponding protrusions 11 and 11a on their respective movement paths, and the protrusions 11 and 11a are positioned on the respective travel paths. A stopper device characterized in that the stopper device is located at a position that moves a friction plate 7a elastically held in a direction intersecting the direction of movement and in a direction that presses the friction plate 7a.