JPS5813299B2 - Pallet swivel device - Google Patents

Description

[Detailed description of the invention] When performing all machining efficiently and consistently on a single part that requires multiple machining processes such as facing, drilling, and tapping, it is necessary to use multiple processing machines in the order of the machining steps. Pallet-type multi-station transfer machines, which are arranged in a straight line and carry workpieces on them, are sequentially transferred from station to station on the machining line using an appropriate transfer drive device to perform the desired machining. This is where you will be exposed.

However, when it is not possible to arrange machines in a straight line due to installation space problems within a factory or other reasons, it becomes difficult to employ the above-mentioned pallet type transfer machine.

In such a case, for example, as shown in Fig. 1, various way machines Ml, M2, M3... are arbitrarily arranged according to the factory space, while the pallet P is transported along each machine. Endless main passage T
At the same time, this main passage T and each machine Ml, M2
, M3..., processing positions S1, S2, S3... are connected by a branch path (not shown), and the pallet that has been processed in the previous process is carried out from that processing position to the main path by automatic or manual operation. Then, the pallet is conveyed along the main path by an appropriate drive device to the branching path connection point for the next process, and then pulled into the processing position of the processing machine to perform the desired processing one after another. A handshake has been adopted.

In this case, the main passage T of the pants P is laid as close as possible to the front part of the arbitrarily arranged machine groups Ml, M2, M3... In other words, the length of the branch path is made as long as possible. In terms of work efficiency and pallet operating efficiency, it is desirable to shorten the length of the passage so that the loss time required for moving the pallet P in and out from the main passage to the processing position or from the processing position to the main passage is as short as possible.

As a result, in the first illustrated example, as many as six curved paths R are inevitably formed in the main passage T, and in some cases, curved paths with different curvatures may have to be installed in several locations. Yes.

From this background, it is clear that the smaller the radius of curvature of the curved path R can be set, the greater the degree of freedom in machine layout and passageway design, and furthermore, the smaller the installation area of the entire machine. There is.

Furthermore, the faster the turning speed of the pallet passing through the curved path is, the higher the operating efficiency of the pallet is, which has the effect of reducing the required number of pallets.

In view of the above-mentioned points, it is an object of the present invention to provide a pallet turning device in which the turning speed of a pallet passing through a curved path is rapid and the radius of curvature is small.

By the way, if no modifications are made to the curved path seen in the past, the curved path will have a constant radius of curvature determined by the bullet size, resulting in an increase in the installation area of the entire machine and an extremely long branch path. It was happening.

For this reason, conventionally, a method has been proposed in which the pallet is raised at the bend, then rotated in a horizontal plane and lowered, but this not only makes the drive device complicated and expensive, but also raises and Since the three operations of turning and lowering are required, there is a drawback that the conveyance speed becomes extremely slow.

The present invention is intended to eliminate such drawbacks, that is, to effectively and appropriately achieve the above-mentioned object, and will be explained below based on the embodiments shown in the accompanying drawings.

FIG. 2 is a partially vertical front view of the pallet P according to the present invention. As is clear from this figure, the pallet 1-P has a pair of grooves 2a, 2 extending in the vertical direction, that is, in the direction of movement, on the bottom surface 1 of the pallet 1-P.
The pallet differs from the conventional pallet only in that b is carved at a symmetrical position with respect to the center line, and the other points, including the point that the workpiece W is fixed by clampers 3, 3, are not different from the conventional pallet.

FIG. 3 is an enlarged plan view of the curved path R portion of the main passage T shown in FIG.

A straight pallet introduction side passage 5 and a pallet discharge side passage 6 equipped with a power roller conveyor 4 are connected to the front and rear ends of the curved path R.

The curved path R is formed by two inner and outer arcuate guide rails 1 and 8 having a common center of curvature, and a ball conveyor 9 is disposed on the inner guide rail γ.

In addition, a pivot shaft 10 is provided at the center of curvature of the curved path R to be rotated by bearings ii and i1 as shown in the third and fourth figures, and an arm 12 is fixed to this pivot shaft 10 with a key 13. One protruding part 12a of the arm 12 extends into the pallet path, and the upper part has a guide piece 14 that engages with the inner groove 2a of the pallet P entering from the direction of the arrow.
will be established.

The other protrusion 12b of the arm 12 has a pin 15 and a joint 16.
It is connected to the telescopic iron 18 of the cylinder 11 via etc.

Note that 19 houses the bearings 11, 11, and the pivot shaft 10,
This is a support plate that supports the arm 12.

As shown in FIG. 5, an inclined surface 2
A movable block 20, which is provided with a vertical surface 20b and a spring support of 1 mm by an anti-compression spring 21, is retractably inserted into the hole 22.

Further, on the opposite side of the movable block 20 with the guide piece 14 in between, an L-shaped lock plate 23 is pivoted by a pin 25 and is constantly urged by an anti-compression spring 24. The upper part forms a stop surface 26 which is still in contact with the front end surface of the pallet P entering, and the lower part has a hole 2 bored parallel to the guide piece 14.
Connect with one end of the sliding rod 28 inserted through the inside of 7.

29 is fixed to the member 30 by a stopper installed opposite the tip block 28' of the sliding rod 28.

Next, the operation of this device will be explained.

When the pallet P approaches the curved path R while traveling on the introduction side straight path 5 shown in the third figure to the right, that is, in the direction of the arrow, by the puff roller conveyor 4, one of the grooves provided in the bottom 1 of the pallet P 2a and the guide piece 14 are engaged with each other while traveling.

Note that before the guide piece 14 and the groove 2a engage, the front end surface of the pallet comes into contact with the inclined surface 20a of the movable block 20, but the pallet itself pushes the movable block 20 down against the anti-compression spring 21. It is impossible to prevent the pallet from progressing.

The front end of the pallet P has a locking rate of 23.
The roller conveyor 4 runs until it comes into contact with the stop horn surface 26 of the roller conveyor 4 and is stopped.

When the pallet P is stopped, the inertia of the pallet applies a force to the lock plate 23 to rotate it clockwise about the pin 25 in FIG. The stop surface 26 securely locks the pallet P without the lock plate 23 rotating to support the pallet P.

Also, at this time, the rear end of the pallet P is connected to the movable block 20.
As it passes through the soil, the anti-contraction spring 210 protrudes due to its elasticity and locks the rear surface of the pants P.

In response to a stop signal from the pallet P, the cylinder 11 is actuated, and the arm 12 rotates clockwise in FIG. 3 together with the pivot shaft 10 in order to extend the iron 18.

As a result, the pallet P is moved around the pivot axis 1 by the guide piece 14.
It is forced to turn with a radius of curvature centered on the zero axis.

At this time, the pallet P has guide rails 1 and 8 extending in an arc shape.
guided by.

When the arm 12 and the pallet P are rotated by 90 degrees and reach the discharge side straight path 6, the cylinder 11 stops, and the stopper 31 installed on the discharge side straight path 6 side and the front surface of the lock plate 23 Stop block 3 attached to
2 come into contact with each other, the lock plate 23 rotates clockwise in FIG. 5 against the spring 24, and the stop surface 2
6 and the front end surface of the pallet is automatically released.

Therefore, the pallet P is discharged by the power roller conveyor 4 on the discharge side straight path 6 toward the machine for the next process in the direction of the arrow.

Note that when a pallet is sent out, the cylinder 17 and arm 12 operate in the opposite direction and return to the position shown in FIG. 3 to prepare for the next pallet to be sent.

As described above, according to the present invention, the pallet is forcibly rotated with a small radius of curvature due to the engagement between the groove carved on the bottom surface of the pallet and the guide piece, so that the curvature of the curved portion of the passage can be reduced. Therefore, not only the installation area of the entire device can be reduced, but also the degree of freedom in the layout of the machine group and the design of the passages is greatly increased, which has the effect of improving work efficiency.

Furthermore, since the pallet is driven by a single movement of the cylinder, the device is simple and inexpensive.Moreover, the pallet rotation speed is fast, so it has many advantages such as high operating efficiency and the ability to reduce the number of pallets. .

The reason why two grooves 2a and 2b are carved on the bottom surface 1 of the pallet P is that when the pallet is discharged in the opposite direction to that shown in Fig. 3, that is, in the upward direction in the figure, the cylinder and arm etc. This is because the turning device is attached at a position symmetrical to the position shown in FIG. 3, and the groove 2b engages with the guide piece 14.

Further, it is preferable that the roller near the curved portion of the power roller conveyor 4 is a slip torque roll whose drive shaft and roller are magnetically coupled to reduce the speed of the pallet.

[Brief explanation of drawings]

FIG. 1 is a plan view showing an example of the machine layout according to the present invention, FIG. 2 is a partially cutaway front view of a pallet 1 used in the present invention, and FIG. 3 is a pallet passageway showing the main parts of the present invention. An enlarged plan view of the curved part, Figure 4 is A in Figure 3.
Only the main parts are shown in the arrow view. FIG. 5 is a sectional view taken along the line II in FIG. 3. M1~M9...
...Machine group, T...Main passage, R...Curved path, P...Pallet, 1...Pallet 1/bottom, 2a, 2b...Groove, 10...
...Swivel axis, 12... Arm, 14... Guide piece, 17...
…cylinder.

Claims (1)

[Claims] 1. In a pallet transport device that transports a pallet carrying a workpiece on a path laid out along a group of machines arranged in an arbitrary pattern, a groove extending in the direction of movement of the pallet is provided on the lower surface of the pallet. On the other hand, a guide piece attached to an arm that rotates as the cylinder expands and contracts is provided at the curved part of the passage, and this guide piece is engaged with a groove provided on the lower surface of the pallet to forcibly move the pallet. A pallet rotating device characterized by being configured to rotate.