JP2000301433A - Pallet clamp structure - Google Patents

Abstract

(57) [Problem] To provide a structure capable of unclamping a clamp claw of a pallet mounted on a main shaft of a machine tool using a coolant without changing the main shaft of the machine tool. SOLUTION: A coolant is supplied under a high pressure by a booster 617 so as to be in an unclamped state against the force of a resilient member 609. As a result, the pressure in the chamber 610 becomes larger than the elastic force of the elastic member 609, and
08 is in the unclamped state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clamp structure suitable for a pallet detachable from a main shaft of a machine tool.

[0002]

2. Description of the Related Art In order to facilitate processing of a work or transfer of the work, a work is conventionally fixed on a pallet, and the pallet is mounted on a processing table or sent out onto a conveyor.

[0003] As described above, the pallet is provided with the clamp claws for fixing the work during processing or transportation. The clamp structure of this clamp claw is
As disclosed in Japanese Patent No. 60772, etc., a piston and a rod having one end attached to the piston are inserted into the cylinder, a clamp claw is attached to a tip of the rod protruding outside the cylinder, and the piston and the cylinder inner wall are connected to each other. A strong resilient member such as a disc spring is placed between the pallets, and the clamp is constantly urged in the closing (clamping) direction. Don't be safe.

[0004] To achieve the unclamped state, a compressed fluid is supplied to a chamber on the opposite side of the chamber in which the resilient member is housed, of the chamber defined in the cylinder by the piston,
The clamp pawl is moved in the opening direction against the resilient member. Incidentally, in Japanese Patent Publication No. 4-60772, a rod having a clamp claw attached to one end thereof is separated from a piston so that an amplifier ramp can be smoothly performed by reducing the resistance during the opening operation, and a ball screw mechanism is provided. These are connected via a.

On the other hand, in the processing station, a prior art in which a pallet is automatically attached to and detached from a processing table by utilizing an accurate positioning function by numerical control (NC) of a machine tool is disclosed in Japanese Patent Application Laid-Open No. 55-1979. No. 70543 and JP-A-55-112753.

[0006]

When a compressed fluid such as compressed air is used to apply a force in the unclamping direction to the clamp claw, the pressure in the fluid chamber in the cylinder overcomes the resilience of the resilient member. It will take some time.

Therefore, it is conceivable to use incompressible hydraulic oil (oil) instead of the compressed fluid. However, if this idea is applied as it is to the devices proposed in JP-A-55-70543 and JP-A-55-112753, a passage for hydraulic oil for opening and closing the clamp claws is separately provided in the machine tool. There must be.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a pallet clamp provided with a clamp claw constantly urged in a clamping direction by a resilient member and detachably attached to a main shaft of a machine tool. In the structure, a coolant (cutting fluid) formed on a main shaft of a machine tool is provided on the pallet.
Forming a coolant flow passage connected to the flow passage, communicating the coolant flow passage with a fluid chamber for applying a force in the unclamping direction to the clamp claw against the resilient member, and further, the coolant flow passage A pressure increasing means (a booster) for supplying a force in an unclamping direction larger than the elastic force of the elastic member to the fluid chamber is connected.

With this configuration, the responsiveness of the unclamping operation is improved, and there is no need to perform special processing on the main spindle of the machine tool. It can be carried out.

Further, the coolant flow path formed on the pallet side is opened by a member on the machine tool side when the pallet is mounted on the spindle of the machine tool, and is closed when the pallet is removed from the spindle of the machine tool. Preferably, a check valve is provided.

[0011] With such a configuration, the apparatus waits in a state in which the coolant is filled in the coolant passage and the fluid chamber in the pallet. In this state, the pallet is connected to the main shaft of the machine tool. When the pressure is increased by the booster (booster), the coolant is already filled in the pallet, and the pressure is immediately transmitted. At the same time, it can be in the unclamped state.

[0012]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 is a schematic perspective view of an entire processing station incorporating a machine tool having a pallet holding structure according to the present invention, FIG. 2 is a plan view of the processing station, FIG. 3 is a side view of the processing station, and FIG. FIG. 5 is a side view of the processing station according to another embodiment, FIG. 6 is a side view showing a pallet stocker of the processing station according to another embodiment, and FIG. FIG. 8 is a side view, and FIG.
FIG. 9 is a view showing a coupling structure between the tip of the main spindle of the machine tool and the pallet, FIG. 10A is an enlarged view of a state where the pallet is held by the main spindle of the machine tool, and FIG. )
Is an enlarged view of the state where the machining tool is held by the spindle of the machine tool,
FIG. 11 is a diagram showing a hydraulic circuit for opening and closing the clamp claws of the pallet, FIG. 12 is a side view showing a state in which the machine tool is transferring the pallet to the processing table device, and FIG. FIG. 14 is a side view showing a balance mechanism of the processing table device, FIG. 15 is an enlarged view of a part of the portion viewed from the direction B in FIG. 14, and FIG.
6 is a view similar to FIG. 14 showing another embodiment, and FIG.
18 is a view showing a table surface of the processing table device, FIG. 19 is an enlarged view of FIG. 18, and FIG. 20 is a sectional view taken along line AA of FIG.

As shown in FIGS. 1 to 4, a base 1 is provided in the processing station, and a machine tool 100 and a processing table device 200 are mounted on the base 1. The pallet stocker 300 is arranged so as to surround the automatic tool changer (ATC) 400 above the machine tool 100.

In the machine tool 100, a turn block 101 is rotatable about a vertical axis in a horizontal plane with respect to a base 1. The pallet stocker 300 comprises a plurality of pallet receiving frames 301.
01 and the machining table device 200
The leading end of a transfer line L1 which is arranged substantially radially around the center of rotation of 00 and also serves to carry in and carry out the work W within the turning range of the machine tool 100, and this leading end is a work supply position 500. Thereby, the machine tool 10
0 is the processing table device 200 and the pallet stocker 30
0 and the workpiece supply position 500.

The machine tool 100 has a support 103 with respect to the turn block 101 about a horizontal axis 102.
Is mounted so as to be tiltable in a vertical plane by driving a motor 104.
Are supported by a motor 106 so as to be able to advance and retreat, and a main shaft (spindle shaft) 107 that is rotated at high speed by a motor (not shown) is supported in the main bearing 105.

As shown in FIGS. 12 and 13,
Male screw rod 11 extending rearward from the support portion 103
The main bearing 105 is mounted on the main bearing 105 via a nut member 111, and the male screw rod 110 is driven by the motor 106.
By rotating the nut member 111, the nut member 111 moves along the guide rod 112, and the main bearing 105 moves forward and backward together with the nut member 111.

As the support portion 103 performs a tilting movement in a vertical plane, the main shaft 107 conforms to the height of the processing table device 200, the pallet stocker 300 or the automatic tool changer 400 as shown in FIG. 3 or FIG. Turn in the direction.

As shown in FIG. 8, a base end of a lever 108 is attached to an end of the horizontal shaft 102 opposite to the motor 104, and a rod of a balance cylinder 109 is attached to a tip of the lever 108. In addition, the weight imbalance caused by the advance and retreat of the main bearing 105 is absorbed.

The structure of the tip of the spindle 107 is a work W
And a machining tool T for performing machining such as cutting and drilling on a workpiece can be selectively held.

A structure for holding the pallet P and the processing tool T by the spindle 107 will be described with reference to FIGS.
A through hole 107a is formed in the main shaft 107 in the axial direction, and a tip of the through hole 107a is a receiving recess 113. As shown in FIG.
When the pallet P is held, the straight shank 601 of the outer block 600 of the pallet P receives the pallet P when receiving the pallet P, as shown in FIG. When the tool T is fitted to the straight portion 113b of the recess 113 to hold the working tool T, the tapered cone portion 700 of the working tool T is fitted to the female taper portion 113a of the receiving recess 113 as shown in FIG. I am trying to do it.

In the present invention, the pallet P and the machining tool T are held by the spindle 107. In this case, if the pallet P and the processing tool T are held at the same position of the receiving recess 113, the pallet P becomes a considerably heavy object when the work W is attached, and the surface of the receiving recess 113 may be damaged. When the processing tool T is held by the receiving recess 113 whose inner surface is damaged, the main shaft 107 rotates at a high speed during processing, so that the rotation axis of the processing tool T is blurred and the processing accuracy with rattling is deteriorated.

Therefore, as described above, the receiving recess 113 is not formed in a simple female tapered shape, but a straight portion 113b is provided continuously to the female tapered portion 113a, and the straight shank 601 of the pallet P is formed by the straight portion 113b.
And a portion of the pallet P is prevented from contacting the female tapered portion 113a.

An annular convex portion 602 is formed on the surface of the outer block 600 of the pallet P facing the main shaft 107, and this convex portion 602 is brought into contact with the end surface of the main shaft 107 in the holding state.

When the entire surface of the opposing surface of the outer block 600 is brought into contact with the end surface of the main shaft 107, there is a possibility that rattling may occur due to a large contact area. Sticking can be prevented beforehand. Also,
When the annular convex portion 602 abuts on the end face of the main shaft 107,
The pallet can be held accurately even if a slight gap or the like occurs between the straight portion 113b and the straight shank portion 601 due to deformation or undulation.

As shown in FIG. 9, a clamping sleeve 115 which can be advanced and retracted (moves left and right in the figure) by a cylinder (not shown) faces into a through hole 107a formed in the main shaft 107.
A gripper 116 having a slit formed in the axial direction is provided on the outside thereof, and a coolant passage 117 is formed inside the clamping sleeve 115.

When the clamping sleeve 115 is located on the left side of the state shown in FIG.
The diameter of the pallet 16 can be reduced and the straight portion 601 of the pallet P can be pulled out from the recess 113. Then, when a cylinder (not shown) is driven from such a state, the clamping sleeve 115 is retracted rightward in the drawing. Then, the male tapered portion of the clamping sleeve 115 enters the gripper 116, expands the gripper 116, and firmly holds the straight portion 601 of the pallet P with the straight portion 113b of the concave portion 113.

The structure of the holding portion of the pallet P is shown in FIG.
As shown in FIG. 7, the shank portion 600 is fixed to the main body of the pallet P via a fixing member 603. Fixing member 6
03 and the shank portion 600 are formed with a common through hole, and the check valve 604 is inserted into this through hole.

The check valve 604 is urged in a protruding direction by a spring 605 provided between the check valve 604 and the main body of the pallet P. When the check valve 604 is not held on the main shaft 107, the land portion of the check valve 604 is formed on the fixed member 603. It comes into close contact with the seat surface 606.

The check valve 604 has a passage 6 therein.
The passage 607 is connected to a coolant (cutting fluid) supply source through a coolant passage 117 in the clamping sleeve 115.

As shown in FIGS. 9 and 11, the coolant from the supply source is released from the clamp pawl 608 through the coolant passage 607 in the check valve 604, the coolant passage 611 in the pallet P, and the coolant pipe 612. It is supplied to a fluid chamber 610 that performs clamping.

The pallet P is provided with four clamp claws 608 for fixing the work W. This clamp claw 608 is attached to one end of the rod 613,
The other end of the rod 613 is inserted into the cylinder 614 and connected to the piston 615. The inside of the cylinder 614 is defined by the piston 615 into the fluid chamber 610 and another chamber 616, and the clamp pawl 608 is always moved in the clamping direction by a strong resilient member 609 such as a disc spring provided in the chamber 616. Being energized. In FIG. 9, reference numeral 618 denotes a stopper. The clamp / unclamp operation of the clamp claw 608 will be described below.

First, when the pallet P is not held on the main shaft 107, the check valve 60 is
Since the coolant flow path 609 and the coolant pipe 610 in the pallet P are closed at 4, the coolant is filled in the coolant flow path 609 and the fluid chamber 610 that applies a force in the unclamping direction to the clamp claw 608. ing. However, since the force of the resilient member 609 is larger than the force given from the coolant in the fluid chamber 610, the clamp claw 608 maintains the clamped state.

On the other hand, FIG. 9 shows a state in which the pallet P is held by the main shaft 107. In this state, the check valve 604 is pushed inward by the clamping sleeve 115 against the elastic force of the spring 605. The land portion of the check valve 604 is separated from the valve seat surface 606 formed on the fixing member 603, and the coolant flow path communicates.

Even if the coolant flow path communicates, the resilient member 6
Since the force of 09 is large, the clamp claw 608 maintains the clamped state. As shown in FIG. 11, the booster 6 can be unclamped against the force of the resilient member 609.
At 17 the coolant is supplied under high pressure. As a result, the pressure in the chamber 610 becomes larger than the resilience of the resilient member 609, and the clamp claw 608 enters the unclamped state.

As described above, a coolant is used as a fluid for operating the clamp claw 608 without using hydraulic oil. Coolant is necessary when cutting or drilling with a machine tool, and by using this coolant as a working fluid, piping for supplying hydraulic oil is not required, and the structure of the main spindle so far is used as it is. be able to.

Further, since the passages and chambers formed in the pallet P are always filled with the coolant, the pressure is instantaneously transmitted when the booster 617 pressurizes the clamp claws 608 to unclamp them. The operation switching between the clamp and the unclamping can be performed reliably and without delay.

On the other hand, the processing table device 200 is
On the other hand, a support block 201 is pivotable about a vertical axis in a horizontal plane, and a horizontal axis 202 is attached to the support block 201. At one end of the horizontal shaft 202, a motor 203 (see FIG. 2) for rotating the horizontal shaft 202 is provided.

The horizontal shaft 202 is provided with a balance mechanism on the other end side of the horizontal shaft 202 in order to rotate the processing table together with the heavy work table and the pallet P on which the work W is mounted.

As shown in FIGS. 14 and 15, this balance mechanism includes a bracket 204a,
The base of the cylinder unit 205 is attached to the bracket 204a, and one end of a rod 204c is attached to the bracket 204b. The lower end of the plate 206 is fixed to the bracket 204a by welding or the like.
The tip of 4c is attached via a nut so that the position can be adjusted. Further, a shaft 207 is rotatably supported on the plate 206, a crank 208 is attached to one end of the shaft 207, a gear 209 is attached to the other end, and a rod of the cylinder unit 205 is connected to the crank 208. A gear 210 provided on the other end of the horizontal shaft 202 and the gear 2
09, a timing belt 211 is stretched.
Here, when the processing table 212 is stopped at a position lateral to the horizontal shaft 202 and is at a position where a torsional force is applied to the horizontal shaft 202, the upper side or the lower side of the timing belt 211 (gears 209, 210) ) Is in a tension state, and a force in the falling direction (rightward force in FIG. 14) acts on the plate 206. In this state, an excessive force acts on the lower end mounting portion of the plate 206, so that the rod 204c prevents the tension plate 206 from falling down.

A rotary joint 213 (see FIG. 17) is provided outside the gear 210 of the horizontal shaft 202. Since the rotary joint 213 is attached to the end of the horizontal shaft 202, a general balance mechanism as applied to a machine tool cannot be employed, and the above-described structure is employed.

The horizontal shaft 202 has the machining table 2
12, the weight of the processing table 212 acts as a torsional moment on the horizontal shaft 202. The cylinder unit 205 is driven, and this driving force is applied to the crank 208, the shaft 207, the gear 209, and the timing belt. Canceling by applying a force in the opposite direction to the torsional force to the horizontal shaft 202 via the 211 and the gear 210,
Balance is maintained. This balance can be maintained at any point 360 ° around the horizontal axis 202.
This can be achieved even when 2 is located.

FIGS. 16 and 17 are views similar to FIGS. 14 and 15 showing another embodiment of the balance mechanism. In this embodiment, a gear 2 is used instead of the timing belt 211.
14, and the other members are the same as those in the embodiment shown in FIGS.

In the machine tool 100 described above, the lever 108 is mounted on the horizontal shaft, and the rod 100 of the balance cylinder 109 is mounted on the tip of the lever 108. When the lever cannot be attached to the shaft, as described above, the movement of the shaft may be transmitted to the balance cylinder via a lever or a crank provided at a distant location via a timing belt or a gear train. .

Next, the structure of the processing table 212 is shown in FIG.
This will be described with reference to FIGS. At four corners on the mounting surface side of the processing table 212, claws 21 for clamping the pallet P are provided.
5, a sensor 216 for confirming the seating of the pallet P is provided at a position inside the clamp claw 215. As a structure of the sensor 216, for example, air is always blown out, and when the pallet P is seated, the air outlet is closed by the pallet P and detected.

A turning motor 217 for turning (90 °) the pallet in a state where the clamp by the claw 215 is released is provided on the back side of the processing table 212 to prevent the pallet P from dropping in a state where the clamp is released. Is provided at the center on the mounting surface side of the processing table 212. The chuck 218 is opened and closed by combining a cylinder unit (not shown) and a link mechanism.

The processing table 212 is provided with an arm 219 which is turned integrally with the pallet P by the turning motor 217. Proximity switches 220 and 221 for restricting the turning position of the arm 219 are provided on the processing table 212 side. And a triangular plate 222 is attached to the arm 219, and the plate 222 is applied to the dampers 223 and 224 provided on the processing table 212 at this turning limit to prevent the pallet P from turning without impact. I try to stop it.

The dampers 223 and 224 are provided with external threads on their outer peripheral portions, and are mounted on the support plate 227 via nut members 225 and 226 so as to be position-adjustable. It has a configuration.

Further, two lifting cylinders 228, 2 are provided at positions away from the center of the back side of the processing table 212.
The locating pin 2 for positioning the pallet P by operating the lifting cylinders 228 and 229 is provided.
30 and 231 appear and disappear on the mounting surface side of the processing table 212.

Next, the pallet stocker 300 will be described. The pallet stocker 300 has a plurality of pallet receiving frames 301 arranged so as to surround the machine tool 100 as shown in FIG. 1 for each pallet receiving frame 301
The pallets P are stored.

Incidentally, according to the present invention, it is possible to process six surfaces (entire surface) of the work W. When processing the work W in a state where the work W is fixed to the pallet P, the processing table 212 is turned,
By turning the pallet P while being held at 12, the pallet P can be processed up to five surfaces. However, the remaining one surface, that is, the surface attached to the pallet P, cannot be processed because the pallet P itself is in the way.

Therefore, in the present invention, as described later, when the work W is processed to a predetermined surface, another pallet P is prepared, the work W is transferred to this pallet P, and the remaining unprocessed Of the surface is processed.

Therefore, in order to process the entire surface of the work W, two types of pallets P are required. In the example shown in FIG. 2, six pallet receiving frames 301 are arranged. Can be processed.

The structure of the pallet receiving frame 301 is as shown in FIGS.
In order to receive the pallet P from the pallet mounting part 302 by providing a stopper 303 for the pallet P at the rear end thereof, the machine tool 10
0, the main bearing 105 is made parallel to the pallet placing portion 302 by the tilting movement of the support portion 103, and in this state, the main bearing 105 is extended toward the pallet placing portion 302,
Thereafter, as shown in FIG.
13, the straight portion 601 of the pallet P is fitted, the clamping sleeve 115 is pulled in, the gripper 116 is expanded, and the pallet P is held by the main shaft 107.

In the embodiment shown in FIGS. 1 to 4, the pallet stocker 300 surrounds the periphery of the machine tool 100 by about 180 °, and the work carry-in line L1 also serves as a work carry-out line. With such a configuration, it is possible to cope with the processing of the three types of workpieces W as described above. However, since the workpiece loading line L1 also serves as the unloading line, there are restrictions on the processing procedure and the like.

FIGS. 5 and 6 show examples in which the work W carry-in line and the work W carry-out line are separated. Here, FIG. 5 is a plan view of a processing station according to another embodiment, and FIG. 6 is a side view showing a pallet stocker of the processing station according to another embodiment.

In this embodiment, the work carry-in line L1 and the work carry-out line L2 are provided on a straight line, and the machine tool 100 is located between the work carry-in line L1 and the pallet stocker 300 on one side of the line and the other side. Table device 20
0 is arranged, the layout is left and right symmetrical as a whole, and the layout has a high degree of freedom with respect to the arrangement of other devices.

On the other hand, since the work carry-in line L1 and the work carry-out line L2 are provided in a straight line, the space for disposing the pallet stocker 300 is reduced. Therefore, in this embodiment, the pallet receiving frame 301 is provided with two upper and lower pallet placing portions 302 so that two types of pallets P are stocked in one pallet receiving frame 301.

The lower pallet placing portion 302 is the same as described above, but the upper pallet placing portion 302 is inclined forward and downward toward the horizontal axis 102 of the machine tool 100, and the pallet P is placed at the front end. A stopper 303 is provided.

As shown in FIG. 1, an automatic tool changer (ATC) 400 disposed above the machine tool 100 includes a tool stocker 401 holding a large number of processing tools T in a gun belt shape, and a tool stocker 401.
And an exchange device 402 for exchanging the tool T between the spindle 107 and the main shaft 107.

The tool stocker 401 is movable in an annular shape, and the changing device 402 is provided with tool holders 4 at both ends of an arm 404 that pivots around a shaft 403 as shown in FIG.
05, and a tool to be returned from the machine tool 100 to the tool stocker 401 in one of the two tool holders 405.
On the other hand, the machine tool 100 is newly added from the tool stocker 401.
The tool T attached to the main shaft 107 is held, and exchange is performed by combining turning and forward / backward movement.

Next, a procedure for processing the six surfaces (entire surface) of the work W such as the cylinder block in the processing station having the above configuration will be described with reference to FIGS. 21 to FIG. 34, FIG.
5, FIG. 26, FIG. 30, FIG. 31, FIG. 33 and FIG. 34 are schematic plan views of the processing station, and the remaining figures are schematic side views.

First, as shown in FIG.
0 is turned around the vertical axis, and the main shaft 107 of the machine tool 100 is turned to the pallet P1 as shown in FIG.
The pallet P1 is held by the main shaft 107. This state is shown in FIG.
But also shown.

Then, the machine tool 100 remains in the above state.
Is turned around a vertical axis in the opposite direction to the above, and as shown in FIG. 23, the pallet P1 held by the main shaft 107 is positioned above the work W with the pallet P1 facing the work supply position 500 as shown in FIG. Face.

Thereafter, the clamp pawl 608 is operated by the clamp / unclamp mechanism using coolant as a working fluid.
Is opened, and when the positioning of the work W is completed, the work W is fixed to the pallet P1 by the clamp claws 608.

Next, as shown in FIGS. 23 and 24,
While the work W is fixed to the pallet P1, the main shaft 107 is tilted upward and the machine tool 100 is turned around a vertical axis, and the pallet P held by the main shaft 107 is rotated.
1 is positioned below the downwardly facing machining table 212,
Further, by tilting the main shaft 107 upward, the back surface of the pallet P1 (the side opposite to the work holding surface) is pressed against the mounting surface of the processing table 212, and the pallet P1 is transferred to the processing table 212 side.

Thereafter, the main shaft 107 from which the pallet P1 has come off.
Then, a processing tool T is attached, and a predetermined surface of the workpiece W is processed by the processing tool T as shown in FIG. When the machining in the state shown in FIG. 13 is completed, the pallet P1 is moved rightward by 9
The right side is turned by 0 ° and then the left side is turned by 90 ° to process the left side. Further, the processing table 212 is turned around the horizontal axis 202 by 90 ° in the vertical plane to process the upper surface of the work.

Thus, the processing of the front, left and right side surfaces and the upper surface of the work W is completed. At this time, the four surfaces of the work W are processed, and the rear and bottom surfaces of the work W (the processing table 21).
2) remains unprocessed.

Therefore, as shown in FIG.
Is retracted, the tool T held at the tip of the spindle 107 is returned to the tool stocker 401, the tip of the spindle 107 is emptied, and the machine tool 10 is moved in the direction of the second pallet P2.
Turn 0. Here, the work W is placed on the pallet P2.
Positioning holes and the like for attaching the upper surface of the device.

The machine tool 100 is moved in the direction of the second pallet P2.
26, the pallet P2 is held by the spindle 107, as shown in FIG. 26, and the machine tool 100 is turned in the opposite direction to the pallet P2 as shown in FIG. It is located above the work W fixed to P1.

After that, the pallet P2 is mounted on the upper surface of the work W. At this time, the work W is sandwiched between the pallets P1 and P2. After this,
The pallet P1 held by the processing table 212 is released, and only the processing table 212 is rotated by about 180 ° around a horizontal axis.
By rotating, the processing table 212 is positioned above the pallet P2.

Next, as shown in FIG. 28, the pallet P2 is held on the processing table 212. In this state,
The pallet P2 is held on both the processing table 212 and the spindle 107. Thereafter, the spindle 107 is moved to the pallet P2.
Then, as shown in FIG. 29, the pallet P1 is held by the main shaft 107, and the engagement state between the work W and the pallet P1 is released.

Thereafter, as shown in FIG.
The pallet P1 held at the tip of the main shaft 107 is returned to the pallet stocker. And
As shown in FIG. 31, a tool T is attached to the tip of the spindle 107, and the tool T is used to machine the remaining surface.

When the six surfaces of the work W have been machined in this way, the tool T is removed from the tip of the spindle 107 again, and the pallet P is held at the tip of the spindle 107 as shown in FIG.
33, the holding state by the processing table 212 is released, and while the pallet P2 is held at the tip of the spindle 107, the machine tool 100 is turned around a vertical axis, and as shown in FIG. Return to the work supply position 500.

Then, as shown in FIG.
2 is returned to the original pallet stocker position, and a series of operations is completed.

[0075]

According to the present invention as described above,
A coolant channel is formed on a pallet that can be attached to and detached from the spindle of the machine tool, and coolant is supplied to the fluid chamber that generates the pressure for unclamping through the spindle of the machine tool. The response speed is faster than the unclamping mechanism using a fluid, and since the coolant is used as the working fluid, there is no need to change the main shaft, so that the cost is free.

By providing the check valve, the coolant flow path and the fluid chamber in the pallet are kept filled with the coolant when the pallet is removed from the machine tool. When it is mounted on the pallet, there is no need to distribute the coolant to the coolant flow path and the fluid chamber in the pallet, so that unclamping can be performed immediately.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a processing station to which a pallet clamping structure according to the present invention is applied.

FIG. 2 is a plan view of the processing station.

FIG. 3 is a side view of the processing station.

FIG. 4 is a side view of the processing station viewed from different directions.

FIG. 5 is a plan view of a processing station according to another embodiment.

FIG. 6 is a side view showing a pallet stocker of a processing station according to another embodiment.

FIG. 7 is a side view of a machine tool.

FIG. 8 is a side view of the machine tool viewed from the side opposite to FIG. 7;

FIG. 9 is a diagram showing a coupling structure between a spindle tip of a machine tool and a pallet.

10A is an enlarged view of a state where a pallet is held by a main spindle of a machine tool, and FIG. 10B is an enlarged view of a state where a processing tool is held by a main axis of the machine tool.

FIG. 11 is a diagram showing a hydraulic circuit for opening and closing a clamp claw of a pallet.

FIG. 12 is a side view illustrating a state where the machine tool is transferring a pallet to the processing table device.

FIG. 13 is a side view showing a state in which the machine tool is processing a workpiece.

FIG. 14 is a side view showing a balance mechanism of the processing table device.

15 is an enlarged view in which a portion viewed from a direction B in FIG. 14 is partially cut away.

FIG. 16 is a view similar to FIG. 14 showing another embodiment;

17 is a sectional view taken along the line CC in FIG.

FIG. 18 is a diagram showing a table surface of the processing table device.

FIG. 19 is an enlarged view of FIG. 18;

20 is a sectional view taken along line AA of FIG. 19;

FIG. 21 is a plan view showing a procedure of an operation in the processing station.

FIG. 22 is a plan view showing a procedure of an operation in the processing station.

FIG. 23 is a plan view showing a procedure of an operation in the processing station.

FIG. 24 is a plan view showing a procedure of an operation in the processing station.

FIG. 25 is a plan view showing a procedure of an operation in the processing station.

FIG. 26 is a plan view showing a procedure of an operation in the processing station.

FIG. 27 is a plan view showing a procedure of an operation in the processing station.

FIG. 28 is a plan view showing a procedure of an operation in the processing station.

FIG. 29 is a plan view showing a procedure of an operation in the processing station.

FIG. 30 is a plan view showing a procedure of an operation in the processing station.

FIG. 31 is a plan view showing a procedure of an operation in the processing station.

FIG. 32 is a plan view showing a procedure of an operation in the processing station.

FIG. 33 is a plan view showing a procedure of an operation in the processing station.

FIG. 34 is a plan view showing a procedure of an operation in the processing station.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Base, 100 ... Machine tool, 101 ... Turn block, 102 ... Horizontal axis, 103 ... Support part, 104 ... Motor, 105 ... Main bearing, 106 ... Motor, 107 ... Main shaft, 108 ... Lever, 109 ... Balance cylinder, 11
0: male screw rod, 111: nut member, 112: guide rod, 113: receiving recess, 113a: female taper portion, 11
3b: straight part, 115: clamping sleeve,
116 ... gripper, 117 ... coolant channel, 200 ...
Machining table device, 201: support block, 202: horizontal axis, 203: motor, 204a, 204b: bracket, 205: cylinder unit, 206: plate, 2
07 ... shaft, 208 ... crank, 209, 210, 214
... Gear, 211 ... Timing belt, 212 ... Processing table, 213 ... Rotary joint, 215 ... Clamp claw, 216 ... Sensor, 217 ... Slewing motor, 218
... Chuck, 219 ... Arm, 220,221 ... Proximity switch, 222 ... Plate, 223,224 ... Damper,
225, 226: nut member, 227: support plate,
228, 229: Lifting cylinder, 230, 231: Locate pin, 300: Pallet stocker, 301: Pallet receiving frame, 302: Pallet mounting part, 303: Stopper, 400: Auto tool changer (AT
C), 401: Tool stocker, 402: Tool changer, 500: Work supply position, 600: Outer block,
601: straight shank part, 602: convex part, 603
... fixing member, 604 ... check valve, 605 ... spring, 606 ... valve seat surface, 607 ... passage, 608
... clamp claw, 609 ... elastic member, 610 ... fluid chamber, 6
11 ... Coolant flow path in pallet, 612 ... Coolant piping, 613 ... Rod, 614 ... Cylinder, 615 ...
Piston, 616: chamber in a cylinder for accommodating a resilient member, 617: booster, 700: tapered cone portion of machining tool T, L1: work carry-in line, L2: work carry-out line, P, P1, P2: pallet, T ... Processing tool, W
…work.

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[Procedure amendment]

[Submission date] July 21, 1999 (July 7, 1999
1)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0071

[Correction method] Change

[Correction contents]

Next, as shown in FIG. 28, the pallet P2 is held on the processing table 212. In this state,
The pallet P2 is held on both the processing table 212 and the spindle 107. Thereafter, the spindle 107 is moved to the pallet P2.
From the support block 201 around the vertical axis 180 °
Turn the holding part of the pallet P1 toward the main shaft 107,
As shown in FIG. 9, the pallet P1 is held by the main shaft 107, and the engaged state between the work W and the pallet P1 is released.
In order to hold the pallet P1 with the main shaft 107, the state shown in FIG.
From the state, the holding of the pallet P2 by the spindle 107 is released,
Next, the processing table 212 is rotated about 180 ° around the horizontal axis.
Rotate the pallet so that the holding portion of P1 faces the main shaft 107.
While holding P1 on the spindle 107, the pallet P1 is
Work table 212 is removed from workpiece W
Rotate it around 180 ° so that the work W faces downward
It may be.

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshikazu Asakura 1-10-1 Shinsayama, Sayama-shi, Saitama Honda Engineering Co., Ltd. F term (reference) 3C016 CA03 CB03 3C033 AA22 AA30 3C042 RB14

Claims (2)

[Claims] 1. A pallet clamping structure comprising a clamp claw constantly urged in a clamping direction by a resilient member and detachably attached to a main shaft of a machine tool, wherein the pallet is formed on a main shaft of the machine tool. A coolant flow path connected to the coolant flow path is formed. The coolant flow path communicates with a fluid chamber for applying a force in an unclamping direction to a clamp claw against the resilient member. A pressure increasing means for supplying a force in an unclamping direction larger than the elastic force of the elastic member to the fluid chamber. 2. The pallet clamping structure according to claim 1, wherein the coolant flow path formed on the pallet side is opened by a member on the machine tool side when the pallet is mounted on the main shaft of the machine tool, and A pallet clamp structure comprising a check valve that closes when the pallet is removed from the main shaft of the machine.