JPH0523898B2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention is a pallet exchange system in which a workpiece fixed to a pallet is automatically fed onto an indexable work table of a machine tool, and the entire pallet is replaced with a machined workpiece. Regarding equipment.

BACKGROUND ART Conventionally, various pallet exchange devices have been proposed. For example, an oval-shaped pallet rotating device that rotates a large number of pallets using a chain drive or the like is installed in front of the work table of a machining center, one of the pallets is positioned in front of the work table of the machining center, and a pallet loader is used to rotate the pallets. The pallet was extruded linearly onto the work table in a horizontal plane, and the pallet was clamped onto the work table by a pallet lamp device on the work table side.

Problems to be Solved by the Invention According to the above-mentioned conventional technology, a pallet rotating device that is equipped with a large number of pallets and rotates them, and a pallet clamp device that fixes the pallets to the work table of a machine tool are integrated. If you try to attach such a pallet changing device to an existing machine tool, you will need to install the pallet rotating device in front of the machining center and the pallet clamping device on the work table of the machining center. Installation was complicated, as hydraulic piping or electrical wiring for the drive device had to be installed separately.

Means for Solving the Problems In order to solve the problems of the conventional technology, the present invention provides a base fixedly installed near the indexing device of the bed body of a machine tool, and a revolving body integrally fixed to this base. Supports the pivot shaft so that it can move vertically and rotate horizontally,
This revolving body is equipped with a plurality of pallet support parts each consisting of a pair of support arms that can push up the lower surface of the upper flange of the pallet and press the upper surface of the lower flange of the pallet. The revolving body is provided with a pallet support part that supports the pallets so as to be rotatable about an axis, so that when one of the pallets is located above the indexing table, at least one of the pallets is located in a standby position, and
The base includes a moving device that is connected to the rotating body and moves each pallet above the indexing table and to the standby position, and a moving device that is connected to the rotating shaft and supports the pallets by actively moving the rotating body up and down together with the rotating shaft. The invention is characterized in that it is provided with a vertical movement device that can be raised and lowered through the pallet and that can release only the clamp of the pallet relative to the indexing table, and further provided with a pallet positioning device between the indexing table and the pallet. .

Operation According to the above configuration, when exchanging a pallet that has been clamped on the indexing table and has been processed with an unprocessed pallet, the rotating body is raised by the vertical movement device, the pallet is unclamped, and the pallet is simultaneously supported. The pallet is pulled upward by the arm to release the pallet positioning between the pallet and the indexing table, and then the rotating body is moved to take out the processed pallet to the standby position and at the same time position the unprocessed pallet above the indexing table. , the rotating body is lowered to position the pallet, and at the same time, this lowering causes the pallet to be clamped onto the indexing table via the support arm.

When it is necessary to index and rotate the pallet using the indexing device during processing, only the clamp is released by the vertical device without releasing the pallet positioning on the pallet on the indexing table, and then the indexing table is indexed. . The pallet is rotated and indexed while being supported by the pallet support, and is again clamped to the indexing table by the vertical movement device.

Embodiment As shown in FIGS. 1 to 5, a main shaft spindle 2 is rotatably supported on a column 1, and a cutter 3 is attached to this main shaft spindle 2. Column 1 is located at the front and back (Z
The main shaft spindle 2 is configured to move in the vertical (Y-axis) direction with respect to the column 1. An indexing base 7 of a known indexing device 5 such as that disclosed in Japanese Patent Laid-Open No. 53-124389 is fixed to the bed main body 4 in front of the cutter 3, and an indexing table 6 is mounted on the indexing base 7 of a known indexing device 5 such as that disclosed in Japanese Patent Laid-Open No. 53-124389. It is indexed at a predetermined angle in a horizontal plane by a rack and pinion, and is clamped to the indexing base 7 at that position by a clamping device (not shown). A bracket 8 made of welded plate material is fixed to the front side of the indexing device 5 of the bed main body 4 with bolts 9, and a base 10 is fixed to the front side of the bracket 8 by positioning it in the vertical direction with a key 11. There is. A pivot shaft 12 is rotatably and vertically supported on this base 10 by sliding bearings 13, 13, and at the upper end of this pivot shaft 12,
A rotating body 14 exemplified as a moving body is fixed. This revolving body 14 is composed of an L-shaped revolving plate 14a that opens at a right angle, and support arms 14b, 14b fixed to opposite ends of the L-shaped part,
A pallet support section 15 is formed by the two opposing support arms 14b, 14b. When one side of this pallet support part 15 is located above the indexing device 5, the other side is connected to the standby device S which is opened by 90 degrees from the indexing device 5.
1, as shown in S2. The support arm 14
b, 14b, the arc-shaped presser foot 16 is attached to the pallet 18.
A, 18B (hereinafter also referred to as pallet 18) is sandwiched between upper and lower flanges 18a and 18b, and is configured to swing around pin 17 by a pin 17.
8b can be pressed. In addition, the support arm 14
Projections 19 and 20 are protruded from opposing surfaces of b and 14b, respectively, and a pallet 18 is formed on the upper surface of the projections 19.
A positioning pin 21 that fits into a positioning hole 18c drilled in the lower surface of the upper flange 18a is provided on the upper surface of the other protrusion 20.
A pallet 22 for receiving the lower surface of each is fixed to each of the pallets. The diameter of the intermediate portion 18d of the pallet 18 is set to be slightly smaller than the circular arc diameter formed by the inner circumference of the presser foot 16 of the opposing support arms 14b, 14b, and the presser foot 16 is in contact with the lower flange 18b. Sometimes, the upper and lower flanges 18a,
The vertical relationship between the dimension between 18b and the support arm 14b is set. Therefore, when the positioning hole pin 21 is removed from the positioning hole 18c of the pallet 18, the pallet 18 can rotate relative to the pallet support part 15.

Next, positioning holes 23a and 23b are drilled in the lower surface of the lower flange 18b of the pallet 18, one each, and a diamond pin 24 and a round pin 25 are fitted into the positioning holes 23a and 23b, and the lower flange of the pallet 18 A positioning plate 27 exemplified as a positioning device including a plurality of pallets 26 for receiving the lower surface of the pallets 18b is fixed to the upper surface of the indexing table 6, and the positioning holes 23 of the pallets 18
When the diamond pins 24 and round pins 25 are engaged with each other, the pallet 18 becomes integral with the indexing table 6.

The moving device for the rotating body 14 includes a cam groove 28 formed on the lower surface of the rotating plate 14a, a swing motor 30 whose output shaft 29 rotates 90 degrees horizontally, and this motor 3.
The Geneva mechanism is composed of a swinging arm 31 connected to an output shaft 29 of 0, and a cam follower 3 that slides in the cam groove 28 at the tip of the swinging arm 31.
2 is rotatably supported, and by switching the swinging arm 31 between the (A) position and (B) position, the two pallets 1
The positions of 8A and 18B are moved between above the indexing device and standby positions S1 and S2.
Further, the cam follower 31 is prevented from coming off the cam groove 28 when the blocks 33, 33 are raised on the back surface of the rotating plate 14a along the longitudinal edge of the cam groove 28.

Next, the up and down device for the revolving body 14 will be explained.
The vertical movement device has a cylinder 35 connected to the lower surface of the base 10 so that the piston rod 34 is located vertically below the pivot shaft 12, and a connecting shaft 37 connected to the tip of the piston rod 34 via a bearing 36. The connecting shaft 37 is fixed to the lower end of the pivot shaft 12, and a ring 38 is screwed onto the lower side of the connecting shaft 37 to the piston rod 34, and a nut 39 prepared on the outside of the ring 38 and a rod side flange 35a of the cylinder 35 are attached to the piston rod 34. A 3-position solenoid operated valve 40 of the pressure port block is connected between the
When the clamping force due to the hydraulic pressure is released by neutralizing the piston rod, a spring 43 is provided which substantially balances the weight applied from above in the axial direction to the rotating body 14, the rotating shaft 12, etc., and the piston rod 34, and prevents the generation of clamping force due to these weights. It is constructed by intervening.

Furthermore, on the upper surface of the base 10, there is a positioning bush 42 having an angle of 90 degrees, which engages with the positioning pin 41 on the back surface of the revolving body 14a and positions the pallet support section 15 on the indexing table 6 and in the standby positions S1 and S2. It is attached in two places.

Now, when the machining of the work on the pallet 18A is completed, the electromagnetic operation valve 40 is switched to the left position, the piston rod 34 is raised, and the pallet support part 15 is also raised and the positioning pin 21 of the support arm 14b is moved to the left position. 18A positioning hole 18
c, and the part 22 comes into contact with the lower surface of the upper flange 18a of the pallet 18A, and the pallet 18
A is disengaged from the round pin 25 and diamond pin 24 of the indexing table 6, and the positioning pin 41
the positioning button 42. Next, this rising end is confirmed by a limit switch (not shown), and the swing motor 30 is operated to swing the swing arm 31 from the (A) position to the (B) position. The cam follower 32 of the swing arm 31 moves along the blocks 33, 33 and the cam groove 28,
The rotating body 14 is rotated 90 degrees to simultaneously move the pallet 18B, which is in the standby position S1, above the index table 6, and the pallet 18A to the standby position S2 in the lower part of FIG. During this rotation, pallet 18A,
18B is the positioning hole 1 of the upper flange 18a.
8c is fitted into the positioning pin 21 of the support arm 14b, so it does not move relative to the pallet support part 15. When this rotation is completed, the electromagnetic switching valve 40 is switched to the right position to lower the piston rod 34, and the rotating body 14 is lowered accordingly and the pallet 18 is lowered.
The lower surface of B is positioned with a round pin 25 or the like, and
The presser foot 16 is placed on the lower flange 18 of the pallet 18B, and is further lowered to release the positioning of the pallet 18B and the support arm 14b.
Clamp the pallet 18B onto the indexing table by pressing the upper surface of the pallet 18B. In this way, the cutter 3 is moved to a predetermined position and machining is started. In this embodiment, when workpiece indexing machining is required, the solenoid switching valve 4 is opened with the cutter 3 away from the workpiece.
0 to neutral and release the hydraulic clamp.
Then, the lower flange 18b of the pallet 18B
It is the weight of the rotating body 14 connected to the piston rod 34, the rotating shaft 12, etc. that is pushing the presser foot 1, but this is canceled out by the spring force of the spring 43, and the presser foot 1
6 comes into slight contact with the lower flange 18b of the pallet 18B, whereby the clamping force by the presser foot 16 is completely released and indexing can be performed using the indexing table 6. While machining is carried out in this manner, the machined workpieces are removed from the pallet 18A at the standby position S, and the unprocessed workpieces are loaded thereon. In this way, palettes 18A and 18B
are alternately placed on the indexing table 6 and clamped, and the workpiece is processed.

In this example, the vertical movement device was constructed using a three-position electromagnetic operated valve and a spring, but the indexing table was rotated by hydraulic pressure to a position where the presser foot came into contact with the lower flange of the pallet. It's okay. Further, the pallets are not limited to two pallets installed at 90 degree intervals, but may be four pallets installed at 90 degree intervals, or two pallets installed at 180 degree intervals. Alternatively, the pallet in the standby position may be transported to the next process, and the pallet from the previous process may be attached to the pallet support section.

Effects of the Invention As described above, in the present invention, a base is fixed near the indexing device of the bed body of a machine tool, and a rotating shaft with a rotating body integrally fixed to this base is supported so as to be vertically movable and horizontally rotatable. This revolving body is equipped with a plurality of pallet support parts each consisting of a pair of support arms that can push up the lower surface of the upper flange of the pallet and press the upper surface of the lower flange of the pallet. The revolving body is provided with a pallet support part that supports the pallets rotatably around an axis so that when one of the pallets is located above the indexing table, at least one of the pallets is located in the standby position, and the base A moving device is connected to the rotating body and moves each pallet above the indexing table and to a standby position, and a moving device is connected to the rotating shaft and actively moves the rotating body up and down together with the rotating shaft to move the pallets to the pallet support section. A vertical movement device that can be raised and lowered via the pallet and that can release only the clamp on the pallet indexing table is provided, and a pallet positioning device is also provided between the indexing table and the pallet, making it easy to replace pallets. The pallet can be clamped onto the indexing table by actively lowering the supporting arm of the revolving body using the vertical movement device.Also, when rotating and indexing the pallet on the indexing table during machining, the vertical movement is The device can index the pallet by releasing only the clamp by the support arm, eliminating the need for a pallet clamping device on the indexing table side, which was separate from the pallet exchange device as in the past, and eliminating the need for parts on the indexing table side. It is possible to reduce the number of points and simplify the mechanism. Moreover,
The pallet changing device itself is integrated around the base, and the pallets do not separate from the pallet support, so they can be easily installed on existing machine tools.

[Brief explanation of drawings]

Fig. 1 is a plan view of a pallet exchange device according to the present invention, Fig. 2 is a side view, Fig. 3 is a cross-sectional view taken from Fig. 1, Fig. 4 is an X view of Fig. 1, and Fig. 5 is a side view. FIG. 2 is a - sectional view of FIG. 1; 2...Main shaft spindle, 3...Cutter, 4...
...Bed body, 5... Indexing device, 6... Indexing table, 10... Base, 12... Rotating axis, 1
4...Swivel body, 14a, 14b...Support arm, 15
... Pallet support part, 18A, 18B ... Pallet, 18a ... Upper flange, 18b ... Lower flange, 28 ... Cam groove, 30 ... Rocking motor,
31... Swinging arm, 35... Cylinder, 43...
...Spring, S1, S2...Standby position.

Claims (1)

[Claims] 1. A pallet changing device used in a machine tool, which is equipped with an indexing device in which an indexing table is supported for indexing freely around a vertical axis in front of a main spindle that moves back and forth, left and right, and up and down relative to the bed body. A base is fixed to the bed body near the indexing device, and a rotating shaft with a rotating body integrally fixed to this base is supported so as to be able to move vertically and horizontally. push up,
In addition, a plurality of pallet support parts each consisting of a pair of support arms capable of pressing the upper surface of the lower flange of the pallet are provided, and each pallet support part supports a pallet rotatably around a vertical axis. The revolving body is equipped with a pallet support part so that when one is located above the indexing table, at least the other one is located in the standby position, and the base is connected to the revolving body and has a pallet support part for indexing each pallet. A moving device that moves the table above and to a standby position, a pallet indexing table that is connected to a rotating shaft and that can raise and lower the pallet via a pallet support by actively moving the rotating body up and down together with the rotating shaft. What is claimed is: 1. A pallet exchange device comprising: a vertical device capable of releasing only a clamp on the pallet; and a pallet positioning device provided between the indexing table and the pallet.