JPS5831626Y2 - pallet exchange device - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an automatic pallet exchange device for automatic machine tools and the like.

Generally, in the automatic pallet changing device of an automatic machine tool, the pallet carrying the finished workpiece is carried out from the table on the machine tool side to the pallet base.
After the pallet carrying the next new workpiece is carried from the pallet base to the chiffle on the machine tool side, the pallet is clamped and one cycle ends.

During this series of steps, chips and swarf on the pallet and workpiece may fall onto the pallet seating surface of the machine tool side chiffle due to vibrations and other factors when the pallet is carried in and out.

This causes a decrease in the machine operating rate due to poor seating of the pallet and a defect in the precision of the processed product.

This idea was made in order to prevent the above-mentioned problems.A cover is provided on the seating surface of the pallet that opens and closes the seating surface using the movement of the pallet itself. An object of the present invention is to provide an automatic pallet exchange device that prevents the pallet from falling.

An embodiment of this invention will be described below based on the drawings.

1 is a table on the machine tool side, where a pallet 15 on a pallet base (not shown) is carried in and clamped by a pallet loader (not shown), and the clamp is released and the pallet is carried out onto the pallet base. It has the same mechanism as the conventional device.

Reference numeral 2 denotes four pallet seats fixed on the table 1, each of which has an air hole 3 opened on its upper surface (pallet seating surface) 2a, and the air hole 3 is connected to a compressed air pipe (not shown). is connected to via a solenoid valve.

Reference numeral 4 denotes two flat protective covers that are provided on the pallet seating surface 2a with a slight gap between them so as to cover each of the pallet seating surfaces 2a' and 2, respectively. , left and right in FIG. 3), a total of four leg pieces 5 are fixed to protrude downward, and a pin 6 is provided on the leg pieces 5 so as to protrude outward.

8 is a guide plate having an L-shaped guide groove 7 consisting of a horizontal groove 7a and a vertical groove 7b extending downward from the front end position of the guide plate;
The table 1 is arranged in correspondence with each leg piece 5 of each protective cover 4.
Four pins are each fixed on the upper surface, and the pins 6 of each leg piece 5 are inserted into the guide groove 7, and the protective cover 4 is moved to the stroke S.
It is configured so that it can reciprocate in a straight line back and forth (in the pallet loading/unloading direction) between the guide grooves 7 and can move downward along the vertical groove 7b at the front end of the guide groove 7.

Each protective cover 4 has two holes 9 slightly larger than the seating surface 2a, corresponding to the seating surface, and the protective cover 4 is free as shown by the solid line in FIGS. 1 and 2. When the protective cover 4 is forcibly moved to the front end as shown by the two-dot chain line, the holes 9 are located away from the seating surfaces 2a.
It is located directly above the

10 is a hook fixed to the front end of each protective cover 40, and when the pallet 15 is carried onto the table 1, it engages with a metal fitting 16 fixed to the lower front end of the pallet 15, and hooks each protective cover 4,4. The pallet is configured to be moved toward the front side (pallet loading direction).

The engagement piece consisting of the hook 10 and the metal fitting 16 does not necessarily need to be provided on both the protective cover 4 and the table 1 so that they can engage with each other; The lower part of the front end of the table 1 may be directly engaged with the lower part of the rear end of the table 1, or the engagement piece provided at the lower part of the rear end of the table 1 may be directly engaged with the rear end of the protective cover 40.

Reference numeral 11 denotes cover floating springs, two of which are symmetrically provided at the front and rear of each pallet seating surface of the table 1, the base end of which is fixed to the table 1, and the curved part of the upper end of which is attached to the lower surface of the protective cover 4. The protective cover 4 is brought into contact with the pallet seating surface 2a, and the protective cover 4 is pushed upward to normally maintain an appropriate distance between the protective cover 4 and the pallet seating surface 2a.

Reference numeral 12 denotes a tension spring that is provided between the ends of the pair of guide plates 8 and a spring hook 13 that is fixed and protrudes from the protective cover 4.
As shown by the solid line in the figure, the pallet is pulled in the unloading direction and pulled back to the rear end position.

Reference numeral 17 indicates a metal fitting 16 provided at the lower part of the front end of the pallet 15.
A wiper fixed to the protective cover 4 is provided so as to sweep up the upper surface of the protective cover 4.

(Fig. 2, Fig. 5) Fig. 4 is a diagram showing a state in which the pallet 15 is carried onto the chiffle 1 on the machine tool side and is clamped, and 20 has a mechanism similar to a conventional automatic pallet exchange device. It is a pallet clamper.

Although not shown, pressure oil flows to the clamp side of the clamp piston provided on the table 1 on the machine tool side.

The pallet clamper 20 is pulled downward, and both ends of the clamper come into contact with the pallet jaws 18, 18 to press the pallet 15 against the seating surface 2a, thereby clamping it.

In the apparatus with the above configuration, when the machined workpiece that has been cut has been completely carried out from the rotary table on the machine tool side to the pallet base (not shown), the leg piece 5 of the protective cover 4 The spring 12 pushes against the protective cover 4 until the pin 6 comes into contact with the rear end of the horizontal groove 7a of the guide groove 7.
, the protective cover 4 completely covers the pallet seating surface 2a as shown in FIG. The air blown out from the hole 3 and hitting the lower surface of the protective cover 4 at right angles is bounced back and flows out from the gap around the pallet seating surface 2a at an appropriate speed, cleaning the surface of the seating surface.

Next, when a pallet loaded with new processed products is carried from the pallet base to the table 1, the wiper 17 provided at the bottom of the front end of the pallet 15 sweeps up the protective cover 4 from the rear end to the front end, and the front end of the pallet 15 After the pallet 15 has completely passed through all the pallet seating surfaces, that is, after the front end of the pallet 15 in the carry-in direction has completely passed through the pallet seating surface located at the frontmost end in the pallet carry-in direction,
The lower metal fitting 16 of the pallet 15 is connected to the hook 1 of the protective cover 4.
0, the protective cover 4 is moved for a stroke S against the elasticity of the spring 12, and the loading of the pallet is completed.

At this point, the pallet seating surface 2a is visible through the hole 9 of the protective cover 4, and the preparation for clamping is completed (FIG. 3).

Next, when pressure oil passes through a clamp piston (not shown) provided on the table on the machine tool side, the pallet clamper 20 presses the jaws 18, 18 of the pallet 15, bringing the pallet 15 into close contact with the seating surface 2a ( Figure 4).

At this point, compressed air is passed through the air holes 3 of the pallet seat 2, and the signal from the pressure switch determines whether or not the pallet 40 is seated on the table 1.
When it is confirmed that the seating is secure, the workpieces on the pallet 15 transferred onto the table 1 are processed by the machine tool.

When the processing of the workpiece is completed and the pallet 15 is unclamped (FIG. 5) and the pallet 15 is carried out to the pallet base, the protective cover 4 is held in place by the hook 10 at its front end due to the elasticity of the tension spring 12. While contacting the metal fittings 16 of the pallet 15, the pallet 15 moves backward by a stroke S, and before the front end of the pallet 15 passes the first seating surface, that is, the front end of the pallet 15 in the carrying direction is positioned at the frontmost side in the pallet carrying direction. Before the pallet passes through the pallet seating surface, the holes in the protective cover are brought to a position farther away from the pallet seating surface, and the protective cover 4 completely covers the pallet seating surface 2a'. Chips are prevented from falling onto the seating surface 2a.

As explained above, the pallet changing device of this invention is provided with a protective cover having a hole through which the pallet seating surface can be inserted, supported on a table so as to be able to move linearly in the direction of loading and unloading the pallet above the pallet seat. If there is no pallet on the side table, the pallet seating surface is always covered by a cover, and when the pallet is advanced from the pallet base onto the machine tool side table.

After the front edge of the pallet has completely passed through all seating surfaces,
The protective cover on the pallet seating surface is moved by the pallet itself, and it is peeked through the hole in the protective cover on the seating surface, indicating that the preparation for clamping is complete, and the pallet is retracted from the table on the machine tool side to the pallet base and carried out. When the pallet is moved, the protective cover moves in the opposite direction as described above under the action of the spring, and all seating surfaces are covered by the protective cover before the rear end of the pallet (relative to the backward direction) passes the first seating surface. This completely prevents chips from falling onto the seating surface while the pallet is being dispensed.

Moreover, the protective cover is interlocked with the pallet via a simple engagement piece provided in at least one direction between the pallet and the protective cover, and a spring provided between the table, and is independent of the pallet clamper. As a result, the interlocking mechanism between the pallet and the protective cover and the structure of the pallet clamper and other devices are extremely simple, and breakdowns are less likely to occur.
It has practical effects such as easy maintenance.

In addition, if chips fall onto the seating surface protection cover, they can be cleaned and removed using the wiper attached to the lower front end of the pallet body when the pallet is being carried in. In addition to completely preventing chips from falling onto the seat, when the seating surface is covered with a protective cover, air is blown out from the air hole in the center of the seating surface to effectively clean the seating surface. be.

[Brief explanation of the drawing]

Fig. 1 is a plan view of the table on the machine tool side of the pallet changing device according to this invention, Fig. 2 is a sectional view taken along line A-A in Fig. 1, and Fig. 3 is a sectional view taken along line BB in Fig. 5. 4 is a sectional view of the table on the machine tool side during pallet flanging, FIG. 5 is a side view of the table on the machine tool side during pallet unclamping, and FIG. FIG. 3 is an enlarged cross-sectional view taken along line C. 1... Machine tool side chiffle, 2... Pallet seat, 2a... Pallet seating surface, 4...
...Protective cover. 9...hole, 10...hook, 11...
... Cover floating spring, 12 ... Tension spring, 15 ... Pallet, 16 ... Metal fittings.

Claims (1)

[Claims for Utility Model Registration] In a pallet exchange device in which a pallet is carried out from a table on a machine tool side and carried into a table on a machine tool side, the pallet that is fixed to the table and carried in is seated on the table. a protective cover that has a plurality of pallet seats and a hole through which the pallet seating surfaces of the pallet seats can be inserted, and that is supported on the table so as to move linearly in the direction of loading and unloading the pallets at a position above the pallet seats; a cover floating spring fixed to the table and acting to constantly push the protective cover upward and increase an appropriate distance between the protective cover and the pallet seating surface;
provided on at least one of the protective cover and the pallet,
When the pallet is carried onto the table, the protective cover is moved along with the pallet in the carrying direction of the pallet, and after the front end of the pallet in the carrying direction passes the pallet seating surface located at the frontmost end in the pallet carrying direction, the protective cover is removed. An engaging piece is provided between the table and the protective cover to bring the hole directly above the pallet seating surface, and the protective cover is constantly pulled in the direction of conveyance of the pallet when the pallet is conveyed from the table. The protective cover is moved along with the pallet in the pallet unloading direction, and before the front end of the pallet in the loading direction passes the pallet seating surface located at the frontmost end in the pallet loading direction, the hole in the protective cover is opened on the pallet seating surface. 1. A pallet changing device characterized by comprising: a spring that brings the pallet to a position further away from the position of the pallet changing device.