JPS6029401Y2 - Pallet exchange device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a pallet changing device for stably maintaining the loading/unloading posture of a pallet when the pallet is loaded into/out of a work table of a machine tool using a pallet loading/unloading device.

When carrying a pallet for workpiece presetting onto the work table of a machine tool, or carrying the pallet out from the work table, a dedicated pallet loading/unloading device is used.
In this case, a clamper is provided on the work table side, which also serves as a guide when loading and unloading the pallet, and also for clamping the pallet on the work table.The clamper is a piston of a clamp actuating cylinder installed in the center of the work table. When the clamper is in the raised state to unclamp when loading or unloading the pallet,
The clamper is in a state where it is supported only at the center, and there is no supporting action at either end on the pallet loading/unloading side, leaving it in an overhanging state.

For this reason, if the weight of the workpiece and pallet is applied to the overhanging part of the clamper, which does not have a supporting function, when loading or unloading the pallet, the clamper will become unstable and its horizontality will change, resulting in a level difference with respect to the pallet frame of the pallet loading/unloading device. It will happen.

This problem becomes more pronounced as the weight of the workpiece and the weight of the pallet increase, and therefore, there is a risk that it will be difficult to transfer the pallet between the work table and the frame of the pallet loading/unloading device.

The present invention aims to overcome the above-mentioned conventional drawbacks by providing a new and improved pallet changing device, and to prevent displacement of the clamper due to the weight of workpieces and pallets, thereby ensuring reliable loading and unloading of heavy pallets. do.

For this reason, in the pallet changing device of the present invention, a lift means is disposed between the work table and the clamper at least on the pallet loading/unloading side of the pallet clamper disposed on the work table to support the weight in conjunction with the unclamping operation of the clamper. This is what I did.

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

In Figure 1, 1 is the base of the machine tool, 2 is the base 1
The feed table 2 is installed to be movable in the X-axis direction indicated by the arrow X above, and a rotary table lifting hydraulic cylinder 3 is integrally assembled approximately in the center of the feed table 2.

The hydraulic cylinder 3 for lifting and lowering the rotary table has a cylindrical hole 4 formed in the center of the feed table 2, as shown in FIG.
A head cover 5 and a rod cover 6 that close the openings at both upper and lower ends of the rod, a piston 7 that is vertically slidably fitted into the cylindrical hole 4 that is closed by the two force bars 5, and the piston 7 are integrated. The upper cylinder chamber (for clamping) 4a is composed of a piston rod 8 that penetrates the rod cover 6 and protrudes upward from the feed table, and a locking pin 9 for the piston 7, and is partitioned by the piton 7. Pressure oil is supplied to the lower cylinder chamber (for unkumpu) 4b from a hydraulic source through an oil passage 10.11 formed in the head cover 5 by an oil passage switching valve (not shown), and to the piston rod 8. The center portion of a rotary table 13 is rotatably and horizontally mounted via a thrust bearing 12, and this rotary table 13
A clamp member 14 for fixing the rotary table 13 is attached to the upper end of the piston rod 8 that protrudes through the piston rod 8 .

Further, an indexing gear 15 is fixed to the lower surface of the rotary table 13 concentrically with the piston rod 8, and a pinion 16 is meshed with this indexing gear 15.
By rotating the rotary table 6 by a drive device (not shown), the rotary table 13 is indexed and rotated to a desired angular position.

Furthermore, coupling gears 17 and 18 are attached to the lower surface of the rotary table 13 and the upper surface of the feed table 2 that opposes the rotary table 13, respectively, to be engaged and disengaged from each other. When the table 13 is raised, it is held in an unlocked state, and the pinion 16 and the indexing gear 15 can freely index and rotate the rotary table 13, and the hydraulic cylinder 3 2 are lowered, they engage with each other to prevent the indexing operation of the rotary table 13, and at the same time, the rotary table 13 is clamped to the clamp member 1.
4 and can be fixed on the feed table 2.

In FIGS. 1 and 2, reference numeral 19 denotes a clamper that has the function of clamping and unclamping the work pallet 20 on the rotary table 13 and the function of guiding the pallets 20 in and out. It consists of a rectangular flat plate body corresponding to the pallet 20, and is installed horizontally on the rotary table 13 so that it can be raised and lowered by a hydraulic cylinder 21 for raising and lowering the clamper.

That is, as shown in FIG. 2, the hydraulic cylinder 21 for lifting and lowering the clamper slides vertically into a cylinder chamber 23 formed by a head cover member 22 buried in the central portion of the clamper 19 and within this cinder chamber 23. The piston rod 25 is integrated with the piston 24 and is integrated with the piston 24 and protrudes from the lower surface of the clamper 19. By being integrally connected to the upper end of the piston rod 8 of the hydraulic cylinder 3, the clamper 19 is supported on the rotary table 13, and an upper chamber 23a for unclamping and a lower chamber 2 for clamping are divided by the piston 24.
3b, the helad cover 5 and piston rod 8 of the hydraulic cylinder 3 for lifting and lowering the rotary table, and the piston rod 25 and piston 24 of the hydraulic cylinder 21 for lifting and lowering the clamper.
Pressure oil from a hydraulic source can be supplied through oil passages 26 and 27 formed through the interior of the oil passage by means of an oil passage switching valve (not shown).

Further, the clamper 19 and the pallet 20 are connected to the pallet 2
0 is placed on the clamper 19 in a surface contact state, and the lower surface of the pallet 20 has guide grooves 28 and 28 (
3), which allows the pallet 20 to be moved horizontally in the longitudinal direction of the clamper 19, and at the same time, a protrusion 28a for forming a guide groove that engages with the lower surface of the end edge 19a is attached to the clamp portion. A reference sheet 29 for setting the vertical position of the pallet 20 is provided on the upper surface of the rotary table 13 facing the rotary table 13.
A reference hole 30 is formed on the lower surface of the pallet 2, and a pallet positioning pin 31, which is engaged with and disengaged from the reference hole 30, is provided protruding from the upper surface of the rotary table 13. Positioning is performed in the X-Y axis direction within the horizontal plane.

The lift cylinder 32 is used to support the clamper 19 when loading and unloading the pallet 20, thereby preventing displacement of the clamper 19 due to the weight of the workpiece and pallet loaded thereon.As shown in FIG. Rotary table 13 and clamper 19 located at both longitudinal ends of
is placed between.

As shown in FIG. 2, the lift cylinder 32 is formed at a desired depth from the upper surface of the rotary table 13, and has a cylinder chamber 34 whose upper surface opening is closed by a rod cover 33, and a cylinder chamber 34 extending vertically into the cylinder chamber 34. It consists of a piston 35 that is slidably inserted, and a piston rod 36 that is integral with the piston 35 and protrudes toward the lower surface of the clamper through the rod cover 33.The upper end of the piston rod 36 is connected to a bolt 37. Pallet clamper 19
The upper chamber 34a of the cylinder chamber 34 partitioned by the piston 35 is connected to the atmosphere through the air passage 38, and the lower chamber 34b of the cylinder chamber 34 is connected to the lower surface of the cylinder chamber 34.
is connected via an oil passage 39 formed in the rotary table 13 to an oil passage 26 communicating with the unclamping upper chamber 23a of the hydraulic cylinder 21 for lifting and lowering the clamper.

In FIG. 1, reference numeral 40 denotes a pallet loading/unloading device installed on the left and right sides of the base 1, and a support stand 41 installed horizontally.
A swivel base 42 for supporting the pallet is mounted on the support base 41 so as to be horizontally rotatable, and the standby pallet 20 on the swivel base 42 mounted on the support base 41 is fixedly held by being locked to the locking member 43. Fixed hook 44 and support base 41
The movable hook 45 is provided movably in the longitudinal direction of the swivel base 42 and is configured to transfer the pallet 20 between the clamper 19 and the swivel base 42.

Further, 46 is a column installed on the base 1 so as to be movable in two axes (in the direction of arrow 2) perpendicular to the moving direction of the feed table 2, and 47 is a column movable up and down on the front side wall of the column 46 (Y
It is a spindle head mounted in the axial direction), and also has a diameter of 48.4
Reference numeral 9 denotes a chip cover that covers the feed table 2 and the guide surface (not shown) of the column 46.

Next, the operation of the device of the present invention configured as described above will be explained.

A pallet loading/unloading device 40 and a work table thereby,
That is, when loading and unloading the pallet 20 between the rotating tables 13, first, the rotating table 42 is rotated 180 degrees, and the first
As shown in the figure, the chamber side faces the rotary table 13,
Then, pressure oil is sent through the hydraulic pressure 11 to the lower cylinder chamber 4b of the hydraulic cylinder 3 for lifting and lowering the rotary table to raise the piston 7 and the entire rotary table 13, and the coupling gears 17 and 18 are disengaged to lower the rotary table 13. It is rotated by the pinion 16 and the pallet 20 is directed to a position shown in FIG. 1 in which it can be carried in and carried out.

Next, a switching valve (not shown) turns the oil passage 26 into a hydraulic source.
The oil passage 27 is connected to a tank to supply pressure oil to the upper chamber 23a of the hydraulic cylinder 21 for lifting and lowering the clamper.
9 as a whole by an amount corresponding to the stroke S of the hydraulic cylinder 21.

Accordingly, as shown in FIG. 2, the edge 19 of the clamper 19
The pallet 20 is left free to move relative to the clamper 19 as the clamp portion 28a clamped by the reference sheet 29 is unclamped and the reference hole 30 is removed from the positioning pin 31.

On the other hand, the pressure oil supplied to the oil passage 26 flows into the lower chamber 34b of the lift cylinder 32 through the oil passage 39, and raises the piston 35 by an amount corresponding to its stroke 52 (S2=St), causing the clamper 19 to overhang. Support the part from below.

Next, the feed table 2 is moved to the end on the rotating table 42 side in FIG. 1, and the movable hook 45 is moved in the direction of arrow A in FIG. Then, by moving the movable hook 45 in the direction of arrow B in FIG.
3, that is, the pallet 20 on the clamp 19, as shown in FIG.
Pull it in as shown by the dotted chain line.

At this time, the levels of the swivel table 42 and the clamper 19 are the same, and the overbang side of the clamper 19 is supported from below by the lift cylinder 32, so that the weight of the pallet 20 including the work is transferred to the overbang side of the clamper 19. Even if the clamper 19
is never displaced.

When the pallet 20 on the rotating table 13 is carried out onto the rotating table 42, the rotating table 42 rotates 180 degrees from the state shown in FIG. ) is placed opposite the clamper 19 in an unclamped state.

Thereafter, the movable hook 45 moves in the direction of arrow A to carry the pallet 20' on the rotating base 42 onto the clamper 19.

When the conveyance of the pallet 20' is completed, a switching valve (not shown) is switched to communicate the oil passage 26 with the tank and the oil passage 27 with the hydraulic power source, so that the pressure oil from the hydraulic source is transferred to the lower part of the hydraulic cylinder 21 for lifting and lowering the clamper. It flows into the chamber 23b and the clamper 1
Lower 9.

As a result, the reference hole 30 is engaged with the positioning pin 31 to position the pallet 20' on the rotary table 13, and the clamp portion 28a is pressed against the reference sheet 29 to clamp the pallet 20' on the rotary table 13.

At this time, the piston 35 of the lift cylinder 32 is lowered to the state shown in FIG. 2 as the clamper 19 is lowered.

Thereafter, the feed table 2 is moved to a processing position facing the spindle head 47, and the rotary table 2 is moved to a processing position facing the spindle head 47, and the rotary table 2 is moved to a processing position facing the spindle head 47.
3 and the feed table 2 to determine the processing position.

In the above example, a hydraulic cylinder was used as the lifting means to support the weight of the pallet clamper when unclamping the pallet clamper, but the cylinder is not limited to this, and a cylinder with a rack and pinion structure, etc. You may also use

Further, the above-mentioned lifting means does not need to be provided at both ends of the clamper 19, and may be provided only on the loading/unloading side of the pallet.
It is desirable that the lifting means provided on the side other than the pallet loading/unloading side is provided with a locking part to prevent lifting.

As described above, according to the present invention, a lift means for supporting the weight in conjunction with the unclamping operation of the clamper is provided between the work table and the clamper at least on the pallet loading/unloading side of the pallet clamper disposed so as to be movable up and down on the work table. As a result, even if the weight of the workpiece and pallet is applied to the clamper during loading/unloading of the pallet, the displacement of the clamper can be prevented, thereby stabilizing the positional relationship between the clamper and the pallet loading/unloading device. This has the effect of reliably carrying in and out pallets.

[Brief explanation of the drawing]

Fig. 1 is a schematic plan view of a machine tool equipped with a pallet changing device according to the present invention, Fig. 2 is an enlarged cross-sectional view showing the details of the part along the line FIG. 3 is a side view of the section marked by ■-■ in the figure. 1...Base, 2...Feeding table,
3...Hydraulic cylinder for lifting and lowering the rotary table, 13
...Rotary table, 19...Clamper, 20.20'...Pallet, 21...
・Hydraulic cylinder for lifting and lowering the clamper, 28...Guide groove, 28a...Clamp part, 29...
Reference sheet, 30...Reference hole, 31...
- Positioning pin, 32...Lift cylinder (lifting means), 40...Pallet loading/unloading device.

Claims (1)

[Scope of utility model registration request] A pallet exchanger that is movably arranged on a machine tool work table and that also serves as a guide for the pallet. In the pallet exchange device, the pallet is carried in and out of the work table via the clamper by a pallet carry-in/out device, in which at least one of the pallet clampers is installed. A pallet exchanging device characterized in that a lift means for supporting the weight in conjunction with the unclamping operation of the clamper is disposed between the work table and the clamper on the pallet loading/unloading side.