JPH0230817B2 - JIDOWAAKUTORITSUKESOCHI - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a machining system in which a workpiece mount on which a workpiece is attached is sequentially exchanged between a machine tool and a stocker to machine the workpiece. The present invention relates to a workpiece mounting device for a workpiece setup station that attaches and detaches a workpiece to and from a workpiece mounting base. In particular, the present invention relates to an automatic workpiece mounting device that automatically clamps or unclamps a workpiece on multiple surfaces of a workpiece mounting table using a workpiece clamper operated by fluid pressure.

[Conventional technology]

Generally, when attaching or removing a workpiece to or from a workpiece mounting table, first, a workpiece mounting table having a workpiece clamper operated by fluid pressure is positioned on a workpiece setup station, a fluid pressure supply section is connected to the workpiece mounting table from the outside, and the clamper is loosened. This is done by tightening the workpiece and attaching it to and detaching it from the workpiece mounting table. Then, the fluid pressure supply section is disconnected from the workpiece mounting base, and the workpiece mounting base is moved from the setup station to the machine tool. The workpiece clamper that has left the workpiece setup station is supplied with the fluid pressure accumulated in the accumulator built into the workpiece mounting base, and continues to hold the workpiece. The workpiece on the workpiece mounting table, which has been processed by the machine tool and returned to the workpiece setup station, is removed from the workpiece clamper and a new unprocessed workpiece is mounted there, as described above, but in the conventional method, During this work, the fluid pressure circuit from the accumulator was completely cut off, and the circuit configuration was such that the pressurized fluid from the fluid pressure supply section was simultaneously turned on and off to all sets of clampers on each side. It was necessary to attach and detach the workpiece to all surfaces at the same time, which made setup work inconvenient.

[Means for solving problems]

The present invention aims to solve the above-mentioned drawbacks of the conventional work setup station.
The present invention provides a novel structure of an accumulator circuit for a workpiece clamper that allows workpieces to be attached and detached from each determined surface of a workpiece mounting table. This makes it possible to mount different types of workpieces on each side of the workpiece mounting base, and it suffices to install a common accumulator for all workpiece clampers, simplifying the configuration.

The above object is an automatic workpiece mounting device that uses fluid pressure to mount a workpiece to a workpiece fixture at a workpiece setup station in a machining system, and is intended to be used to position and place a workpiece on a machine tool and setup station, or to move the workpiece between the workpieces and the setup station using a conveyance device. a workpiece mounting table capable of clamping a workpiece on multiple surfaces using a workpiece clamper operated by fluid pressure;
a fluid pressure receiving part that engages with a fluid pressure supply part when the workpiece mounting base is positioned and placed on a workpiece setup station; a fluid circuit, provided in the middle of the fluid circuit,
an accumulator that backs up fluid pressure when the workpiece mounting base moves from a workpiece setup station and the fluid pressure supply is cut off; and an accumulator that performs fluid pressure backup when one surface of the workpiece mounting base is indexed on the workpiece setup station. This is achieved by means of an automatic workpiece mounting device comprising an accumulator disconnection means in which only the fluid circuit leading from the workpiece clamper to the workpiece clamper on its indexed side is interrupted.

Other objects and effects will become clearer from the following preferred embodiments of the invention.

〔Example〕

First, the positional relationship between the work setup station WSS and the machine tool according to the present invention will be explained with reference to FIG. Work setup station
The WSS is installed with a pallet changer 19 interposed between the front bed 3 on the front side of the machine tool 2 and the stocker 1 (not shown), and has a workpiece mounting base consisting of a pallet 6a and a tombstone 7 fixed to its upper surface. A taper cone 5 provided on a swivel base on the stocker 4 is fitted into a tapered hole on the lower surface of the pallet 6a to detachably hold it in a predetermined position. A work clamper (not shown) for removably fixing the work 8 is installed on the side surface of the tombstone 7. At this work setup station WSS, an unprocessed work is attached to the side of the tombstone 7 and is waiting.
When exchanging pallets, as shown in Figure 3,
The two pairs of changer arms 9, which were waiting in the same direction, rotate 90 degrees in the Y direction when replacing the pallet, and move the pallet 6a on the work setup station WSS and the table 1 on the front bed 3, respectively.
0 and lift it up. Then, it is rotated 180 degrees in a horizontal plane with respect to the central axis, and the pallets 6a and 6b are replaced and placed. Work setup station WSS
Now, remove the workpiece on the pallet 6b and attach a new workpiece again. On the other hand, the table 10 is movable on the front bed 3 in the horizontal plane in the X direction (in the direction perpendicular to the paper in FIG. 2) by a drive means (not shown), and the column 12 of the machine tool 2 is movable on the rear bed 13 The main shaft 15 attached to this column 12 can be moved in the Y direction by a Y-axis feed motor 16 in a horizontal plane (in the left-right direction in FIG. 2) by a Z-axis feed motor 14. It is movable in the vertical direction (in FIG. 2). Therefore, the tool 11 gripped and fixed on the tip of the main shaft 15 is moved around the table 10 by movement in these X, Y, and Z directions.
It becomes possible to perform desired cutting on the work 8 placed on the upper pallet 6a. The upper part of the table 10 can be rotated and indexed in a horizontal plane (not shown), and the workpieces 8 on each side of the tombstone 7 on the pallet 6a can be sequentially indexed toward the main shaft 15 and processed. When the machining of the workpiece 8 is completed, the arm 9 of the pallet changer 19 is operated again and the above-mentioned operation is repeated.

Next, the work setup station according to the present invention
We will describe the configuration of WSS.

In FIG. 1, the setup station WSS includes a swivel table 21 mounted on the top of a base 4 fixed on the floor via legs 26 so as to be rotatable about a vertical axis. Four taper cones 5 protrude at equal angular positions on the upper surface of the swivel table 21, and a pallet 6 is placed on these with taper holes 5a drilled at corresponding positions on the lower surface thereof fitted. It is placed. A four-sided tombstone 7 having a rectangular parallelepiped outer shape is integrally fixed to the upper surface of the pallet 6 with bolts or the like.

Each of the four sides of the tombstone 7 has a workpiece 8
A workpiece mounting means is installed to hold the workpiece in a predetermined posture. The workpiece mounting means includes two edge locators 24a and 24b fixed to predetermined positions of a fixture plate 23 fixed to each side of the tombstone 7 with bolts 22, extending in the horizontal and vertical directions; In order to press the workpiece 8 against the edge locators 24a, 24b, workpiece clampers 25a, 25b are provided with actuating rods that operate perpendicularly to the direction of extension of the respective edge locators, and the workpiece 8 is moved to a fixture plate. It consists of two workpiece clampers 25c and 25d for pressing against the surface of 23. The workpiece 8 is transported by a robot or the like (not shown) from a workpiece storage shelf (not shown) adjacent to the workpiece setup station WSS to the vicinity of one side of the tombstone 7, and is first transferred to the workpiece clamper 2.
5a, the horizontal edge locator 2
4a, then the vertical edge locator 24b by the action of the workpiece clamper 25b, and finally the workpiece clampers 25c and 25d so as to prevent it from lifting off the fixture plate 23. and fixed in place. Once the workpiece has been attached to one side, the workpiece mount is rotated 90 degrees around its vertical axis to point the new side into the robot's working area, where the above procedure is repeated and a new workpiece is attached. . This operation is performed sequentially on all sides of the tombstone 7.

Next, a mechanism for rotating the aforementioned workpiece mounting base by a predetermined angle (90 degrees in this example) will be explained. As shown in FIGS. 1 and 4, a swivel base 21 is mounted on the upper part of the base 4, and its annular rim 2
The annular rim 4 of the base 4 is rotated by four rollers 31 and 32 installed at equal angles on the base 4.
The rim 4a is in engagement contact with the top and side surfaces of the rim 4a and is rotatable along the rim 4a. Here, the roller 31 supports the vertical load acting on the swing 21,
The roller 32 supports the radial load acting on the pivot 21. Annular rim 2 of the swivel base 21
Four notches 33 are provided at exactly equal angles on the inner peripheral surface of 1a. On the other hand, a motor 34 is fixed in the interior space of the base 4 with its output shaft facing vertically upward, and a pinion 35 is attached to its tip. The pinion 35 is configured to mesh with an internal gear 36 fixed along the inner circumference of the swivel base 21, and when the pinion 35 is rotated by the motor 34, the swivel base 21 is rotated via the internal gear 36. Inside the base 4 is an index roller 3 with a cylinder 37 provided at the tip of its operating rod.
8 is positioned and fixed to the swivel base 21 so that the inner circumferential surface thereof is directed. The index roller 38 has the function of fitting into the notch 33 and holding the rotating base 21 in a fixed position when the rotating base 21 is stopped. With this configuration, when it is necessary to turn the swivel table 21 by 90 degrees in order to attach or detach a workpiece to a new side surface of the tombstone 7, an actuation signal for retracting the actuating rod from the control device (not shown) is sent to the cylinder 37. The index roller 38 moves backward from the notch 33, and the swivel base 21, to which an activation signal is sent to the motor 34, rotates approximately 1/4 and then stops. The actuation signal is then again given to the cylinder 37, and the actuation rod moves forward and forces the index roller 38 into the next notch 33 facing it. At this time, if the arcuate rotation of the swivel base 21 by the motor 34 is not accurate, the swivel base 21 will be rotated by the index roller 38 by the forward movement of the operating rod.
It is naturally displaced and indexed to the correct position by the action of the component force applied to it.

Pressurized fluid for operating the work clampers 25a to 25d to attach and detach the workpiece 8 is provided on the workpiece clamper side from a conduit connected to a fluid pressure supply source extending through the hollow interior of the base 4. The workpiece is supplied via a conduit, and as mentioned above, the workpiece mounting table consisting of the tombstone 7 and the pallet 6 is connected to the table on the front bed 3 by the pallet changer 19 to the workpiece setup station WSS and the machine tool. 10, and even if it is inside the workpiece setup station WSS, it repeats 1/4 rotation in order to attach the workpiece to each side of the tombstone 7. It is necessary that the base 4 and the workpiece mount be configured to be engageable and detachable. Next, this engagement/disengagement mechanism will be explained.

Inside the tombstone 7, there are 4
A large number of pipes for pressurized fluid leading to the sets of workpiece clampers 25a to 25d are arranged, and as shown in FIG. 6 protrudes downward toward the through hole provided in the center. These 40 plugs 40 are provided for each set of work clampers, for a total of 40 plugs, and these 10 plugs include the four work clampers 25a to 25d described above.
(2 pipes each x 4 sets = 8 pipes) for supplying and returning pressurized fluid to each of the pipes (2 pipes each x 4 sets = 8 pipes), which are provided to the work clamper even if the work mounting base is disconnected from the fluid pressure supply source, as described later. A pipe (1 piece) for replenishing pressurized fluid to an accumulator for supplying fluid pressure, and a pipe (1 piece) for pressurized air used for checking the installation posture of the workpiece 8 on the side of the tombstone, which will be described later. 1 piece)
corresponds to each. On the other hand, on the lower surface of the bottom wall of the base 4, a vertically moving cylinder 41 is attached to the operating rod 4.
The rod 41a is fixed in a vertical direction with the rod 41a facing upward, and a holder 42 is attached to the tip of the rod 41a. At the top of the holder 42 is a socket 4 for a pipe joint.
A socket block 43 with a portion 5 fixed upward is loosely fitted and held. A flexible rubber hose 44 is connected to the lower part of the socket block 43 and communicates with a socket 45, and extends to a pressurized fluid source (not shown). These sockets 45 are arranged so that workpieces can be sequentially loaded and unloaded in correspondence with the set of plugs 40 attached to the set of workpiece clampers that have occupied the workpiece load/unload position by minute rotation of the swivel base 21. Only one set, ie, ten plugs, are arranged on the same axis as the plugs 40. A rubber hose 44 is also provided corresponding to each socket 45. The cylinder 41 operates and its operating rod 4
When 1a is raised, each socket 45 is fitted with a corresponding plug 40, as shown by phantom lines. During this upward movement, the holder 42 slides through a through hole provided in a portion thereof onto a pair of guide rods 46 vertically erected with their lower ends held by the bottom wall of the base 4 via a bush 47. You will be guided. The upper end of this guide rod 46 is also inserted into a hole provided in a part of the base 4 via an O-ring 48 about ±
Runout of about 1mm is maintained. Further, the actuating rod 41a and the holder 42 are attached via a spherical washer 49, and the holder 42 is rotatably movable. Furthermore, the socket block 43
The mounting between the holder 42 and the holder 42 also allows for free movement of approximately ±1 mm in two horizontal axes directions. Therefore, these flexible mounting methods allow some flexibility in the movement of the holder 42. With this flexible connection means, all the tombstones 7 used in this processing system can
Errors in position and angle between each set of plugs 40 provided corresponding to the work clampers on each side of the workpiece set-up station and one set of sockets 45 of the work setup station can be easily absorbed. In addition, 2
Reference numerals 8 and 29 denote a limit switch for detecting a rise and a limit switch for detecting a fall, respectively, for confirming that the lifting and lowering operation of the holder 42 is completed.

Next, the fitting mechanism between the plug 40 and the socket 45 will be explained in detail. These pipe fittings have a mechanism in which they are self-sealed to prevent pressurized fluid from leaking when disconnected, and automatically communicate when connected. As shown in FIG. 6, in the socket 45, an inner cylinder 51 is slidably inserted into an outer cylinder 50, and a fixing rod 52 is provided passing through the inner cylinder 51 in the axial direction. fixed rod 5
The lower threaded portion of the collar 52 is axially regulated by a hole snap spring 50a of the outer cylinder 50.
b, and is tightened to the collar 52b with a nut 52c. Therefore, the fixed rod 52 is attached to the outer cylinder 5.
It is immovable with respect to 0. The inner cylinder 51 has a spring 5
3 toward the opening 54 of the outer cylinder 50 (upward in FIG. 6), thereby forcing the gasket 55 fixed to the periphery of the tip of the piston rod 52 to the large diameter portion of the tip of the piston rod 52. 52a. Further, 56 is an O-ring installed between the inner and outer cylinders. With this configuration, pressurized fluid supplied from a rubber hose (not shown) connected to the base of the outer cylinder 50 passes through the inside of the outer cylinder 50 and the inner cylinder 51 and reaches the tip thereof, where the piston rod 52 It is self-sealed by the large-diameter portion 52a to prevent leakage to the outside. On the other hand, the plug 40 includes a piston rod 59 slidably in the axial direction inside a cylindrical body 58 having a flange 57a with a tip opening 57 projecting inward. The piston rod 59 has a collar 58b which is regulated upwardly by a hole snap spring 58a in the cylinder 58.
is guided through and urged toward the tip opening 57 by a spring 60. Due to this biasing force, the large diameter portion 59a at the tip of the piston rod 59 is tightly engaged with the inner surface of the flange 57a via the packing 59b. With this configuration, the pressurized fluid in the pressurized fluid conduit on the tombstone side connected to the base of the cylinder 58 passes through the inside of the cylinder 58 and reaches the tip opening 57.
However, at this point, the large diameter portion 59a of the piston rod 59 self-seals to prevent leakage to the outside. The above is an explanation of the self-sealing mechanism when both pipe joints are separated.

The inner diameter of the open area of the outer barrel 50 of the socket 45 is large enough to receive the distal end area of the barrel 58 of the plug 40 and the flange 5 of the barrel 58.
7a has approximately the same diameter as the tip of the socket 45. Therefore, as shown in FIG.
When the cylindrical body 58 of the plug 40 is inserted into the outer cylinder 50 of No. 5, the cylindrical body 58 resists the urging force of the spring 53 and causes the inner cylinder 51 to retreat. The large diameter portion 52a of the fixed rod 52 is made to have a smaller diameter than the opening 57 of the cylindrical body 58, so as the cylindrical body 58 moves inside the socket while retracting the inner cylinder 51,
On the contrary, it enters into the cylindrical body 58 and moves the piston rod 59 on the plug side backward against the biasing force of the spring 60. Through these series of operations, both rods 5
The sealing action of the large diameter portions 52a and 59a of No. 2 and 59 is released, and the pressurized fluid can flow between the two pipe joints.

In order to smoothly perform the fitting operation between the pipe joints described above, in the present invention, a pair of centering pins 61 are provided in the socket block 43 together with the socket 45.
On the other hand, a plug 40 is also installed on the workpiece mounting stand side.
A centering hole 62 corresponding thereto is also provided. With this configuration, when the socket block 43 rises, the centering pin 61 first enters the hole 62, and its tapered tip allows the two pipe joints to fit together accurately while self-correcting some positional errors. . During this fitting operation between the two pipe joints, a fairly large lifting force acts on the workpiece mounting base, and the workpiece mounting base tends to lift off from above the base 4. A clamping device described below is provided to counteract this force. In FIG. 5, the left side of the center line shows the locked state, and the right side shows the unlocked state. As shown in the figure, this device consists of a pair of L-shaped clamp levers 71, one end of which is rotatably supported on the upper part of the base 4.
When the pallet 6 is rotated upward (to the left in FIG. 5), the other end of the hook shape engages and contacts the engagement step 72 provided in an annular shape on the inner peripheral surface of the pallet 6 to prevent it from rising. When it locks in place and rotates downward (5th
The one on the right side in the figure is configured to release the lock. This locking/unlocking operation is performed in conjunction with the lifting and lowering movement of the holder 42 of the socket block 43. That is, a pressing block 73 is fixed to a part of the holder 42, and a pressing pin 75, which is biased outwardly by a compression spring 74 and whose tip slightly protrudes outside the pressing block 73, is housed in its hollow interior. has been done. The pressing block 73 and the pressing pin 75 are arranged at a position where they can engage and come into contact with the back surface of the lever 71. When disconnecting a pipe joint with the holder 42 in the lower position,
In the unlocked state shown on the right side of FIG. 5, the lever 71 is supported so as to rest on the upper surface of the pressing block 73. When the holder 42 holding the socket 45 starts to rise in order to connect both pipe joints, the upper surface of the press block 73 and the sloped part 73a following it rise while contacting the back surface of the lever 71, and the lever 71 is gradually pushed up and rotated (counterclockwise on the left side in FIG. 5), and its tip is engaged with the engagement stepped portion 72. Then, when the fitting of both pipe joints is completed, a pressing force is further applied to the back of the lever 71 by the action of the pressing pin 75,
Lock this completely. Conversely, when the holder 42 is lowered from this state, the lever 71 rotates in the opposite direction in the reverse order as described above, the locking state between the engagement step 72 is released, and the workpiece mount and base 4 are locked. There is a free state between. By this mechanism, the work mounting base is locked to prevent it from coming off the base 4 at the same time as the fitting operation of the pipe joints, and is unlocked at the same time as the disconnection operation.

The work setup station of the present invention further includes a mechanism for checking the attachment posture of the work 8 on each side of the tombstone 7. This check mechanism is performed using pressurized air supplied from one of the fluid pressure supply pipes mentioned above. That is, as shown in FIG. 8, this pressurized air pipe 80 is branched and opens into the surface of each edge locator 24a, 24b facing the workpiece 8, and the workpiece mounting surface of the fixture plate 23. . Therefore, if the workpiece 8 is in the correct position, the fixture plate 2
If the workpiece 8 is not held on the edge locators 24a, 24b or the fixture plate 23, a gap will be created between the workpiece 8 and the edge locators 24a, 24b or the fixture plate 23, through which the pressurized air will leak, reducing the back pressure in the piping. decreases. By detecting this pressure drop with an appropriate sensor, a warning is issued to prevent accidents due to mistakes.

Next, the accumulator 90 built into the workpiece mount and the fluid pressure supply circuit related thereto will be explained. As mentioned above, when the fluid pressure supply part provided in the workpiece setup station WSS and the piping to the workpiece clampers 25a to 25d are disconnected, the accumulator continues to supply fluid pressure to the latter to move the workpiece. It has a function to continue grasping.

FIG. 9 shows a plan view of the inside of the tombstone 7 with the top cover 7a removed. In the center of the inside of the tombstone 7, there is a plug 40 of piping for supplying fluid pressure to the work clampers on the four sides. are shown in four sets of 10 each, for a total of 40 (each set is surrounded by a chain double-dashed line to make the drawing easier to understand). A total of four centering holes 62 described above are provided at equal angular positions between each set of plugs. These are all fixed to the tombstone 7, so when the workpiece mounting base is indexed and rotated by 90 degrees, the plugs 40 and centering holes 62 of each set also rotate accordingly and are sequentially moved to new positions. occupies One of these positions is a position that can be engaged with the aforementioned socket 45. Therefore, the pair of centering holes 62 that happen to occupy the engageable position fit into the pair of centering pins 61. A plunger 82 is inserted into each centering hole 62 to open and close an accumulator circuit shutoff valve 81 for each set of workpiece clampers. On the other hand, when one of the pair of centering pins 61 engages with the centering hole 62, it has the function of pushing up the plunger 82 and operating the accumulator circuit disconnection valve 81. The work clamper on the side of the tombstone that has occupied the position is cut off from the accumulator and is instead switched to supply from the fluid pressure supply piping of the base 4, as will be described later. Unless the plunger 82 of the intermittent valve 81 is pressed by the centering pin 61, fluid pressure from the accumulator 90 acts on the workpiece clamper. Here, the other of the pair of centering pins 61 is hollow, and the centering hole 62
When the plunger 82 is inserted into the hollow part, the plunger 82 does not operate the shutoff valve 81, but only performs a centering action between the fluid pressure supply part and the fluid pressure reception part.

FIG. 10 shows an example of a fluid pressure supply piping circuit to a workpiece clamper. Although the figure shows the circuit leading to one set of work clampers on the first side of the tombstone 7, the circuits for the work clampers on the other sides are also connected in parallel thereto. What is shown below in the figure is the 10
As for the hydraulic oil pipe, a pair of pipes 84a and 84b for supplying and returning fluid pressure for each workpiece clamper is configured to be switchable by a directional control valve 83, The supply side piping 84a is connected during gripping, and the return side piping 84b is connected when releasing the workpiece. The pipe 84c is used to supply fluid pressure to an accumulator 90, which will be described later.
The pressurized air pipe 80 is connected to a compressor 85 which is a pressurized air source provided on the base side, and a back pressure drop detection sensor 86 is installed in the middle of the pipe.
is installed. As mentioned above, this sensor 86 is used to check the mounting posture of the workpiece.

In the illustrated state where the socket 45 and the plug 40 are separated, the workpiece clampers 25a to 25
Hydraulic oil pressure is supplied to d from an accumulator 90. This makes it possible to continue to reliably grip the workpiece even if the workpiece mounting base is removed from the workpiece setup station and transferred to the machine tool side. Next, at the workpiece setup station, when the socket and plug are connected by the aforementioned engagement operation, fluid pressure is directly transmitted to the workpiece clampers 25a-25d through the socket-plug connection. at the same time,
Accumulator circuit intermittent valve 81 is connected to centering pin 61
is switched under the action of , and fluid pressure from the accumulator is cut off. However, this switching is only performed for the workpiece clamper on the first side.
The work clamper on the other side continues to be supplied with fluid pressure from the accumulator. By operating the directional switching valve 83 in this state, it becomes possible to attach and detach only the workpiece on the first surface.

Furthermore, in the illustrated embodiment, two types of accumulators 90 are installed: a high-pressure type 90a and a low-pressure type 90b. The reason for this will be explained next.
The workpiece being machined must be gripped by the workpiece clamper with such gripping force that it will not be displaced from the mounting position due to cutting resistance. However, if this gripping force is too strong, the workpiece will be deformed,
If you continue machining and release the clamp on the workpiece, the desired accuracy may not be achieved. That is, it is desirable that the workpiece be gripped with the minimum necessary force that does not cause such deformation. However, this suitable gripping force varies depending on the progress of machining the workpiece, and in the case of rough machining, such precision is not required, but rather it is necessary to grip with a strong gripping force to withstand large cutting forces. On the contrary, in the case of finishing machining, the cutting force is small and machining accuracy is required, so a weak gripping force is desirable. Two types of accumulators, ie, a high-pressure accumulator 90a and a low-pressure accumulator 90b, are provided so that this gripping force can be used properly, and are configured to be switchable depending on the situation. This will be explained below.

As shown in FIG.
a and 90b are connected to a work clamper pressure oil pipe 84a in parallel with each other via a high/low pressure switching valve 86. The switching valve 86 switches the accumulator 90 by pushing either of the two plungers 87a, 87b that engage with its operating rod.
It has a function of communicating either one of a or 90b with the piping 84 and blocking the other. Therefore, by pressing the plunger 87 and selectively communicating the piping 84a with a desired accumulator as necessary, it is possible to change the gripping force of the workpiece by the workpiece clamper. As shown in the figure, limit switches 88a and 88b are installed to sense the operation of each of the plungers 87a and 87b, and signals from these are sent to the base 4.
It is configured to be transmitted to a high pressure/low pressure setting valve 89 provided in a fluid pressure supply pipe 84c to the side accumulator. The setting valve 89 receives this signal and changes the fluid pressure supplied to the pipe to match that of the selected accumulator, and the next time the socket 45 of the fluid pressure supply section and the plug 4 of the fluid pressure receiving section are engaged. When this happens, a predetermined fluid pressure is supplied to the accumulator. Plunger 8 for switching high and low pressure switching valve 86
The operation of pushing in 7a or 87b may be performed by a robot for replacing the workpiece at the workpiece setup station, or may be performed by an operator.
Also, on the machine tool side, the relationship between the spindle and the workpiece is
It can also be performed by relative movement using NC commands.

Next, the internal structure of the accumulator 90 will be explained. As shown in FIG. 10, the accumulator 90 is provided with an adjustment screw 101 at one end of a cylindrical body 100, whereby a spring receiver 102 can be set at a predetermined position inside the cylindrical body 100. A piston 103 is installed inside the cylindrical body 100 so as to be slidable along the inner wall, and is pushed upward by fluid pressure introduced from an inlet port 104 provided at the other end of the cylindrical body 100. . A compression spring 1 is provided between the spring receiver 102 and the piston 103.
05 is interposed to urge the piston 103 downward. With this configuration, when fluid pressure is introduced into the cylinder 100 from the inlet port 104, the piston 103 is pushed upward and the compression spring 1
05 to balance its biasing force with fluid pressure. Therefore, even if the plug 40 is removed from the socket 45 and the fluid pressure supply source is disconnected, the inlet port 1
The fluid pressure in the pipe connected to 04 is maintained at its original value. By adjusting the adjusting screw 101, it is possible to change the set pressure.

In the illustrated embodiment, two accumulators for high pressure and low pressure are provided and used by switching between them as appropriate, but only one accumulator is provided and the set pressure can be changed as necessary as described above. You can also get the same effect.

Alternatively, the number of dedicated accumulators connected to the clampers of each workpiece mounting surface of the workpiece mounting table may be provided as many as the number of mounting surfaces, and the fluid circuit leading from each accumulator to each clamper may be provided with an interrupting means.

〔Effect of the invention〕

As described in detail above, according to the present invention, the fluid pressure supply circuit from the accumulator to the workpiece clamper is constructed so that it can be connected and disconnected to each side of the workpiece mounting base, so that it can be connected and disconnected independently to each side of the tombstone. Workpieces can now be attached and detached, greatly improving workpiece setup work. Furthermore, it has become possible to attach different types of workpieces to each side. or,
Since it is only necessary to provide one (one or one set) common accumulator for each set of work clampers, the configuration of the entire apparatus is extremely simplified.

[Brief explanation of drawings]

Fig. 1 is a side sectional view of an embodiment of the workpiece setup station according to the present invention, Fig. 2 is a side view showing the positional relationship between the workpiece setup station and the machine tool, and Fig. 3 shows the action of the pallet changer. Fig. 4 is a cross-sectional view taken along the - line of Fig. 1, and Fig. 5 is a plan view taken along the - line of Fig. 4 showing the locking/unlocking mechanism of the workpiece mount. Fig. 6 is a side sectional view showing the state of the pipe joint in a self-sealing state, Fig. 7 is a side sectional view showing the state of the pipe joint in a communicating state, and Fig. 8 is a side sectional view showing the state of the pipe joint in a communicating state. 9 is a plan view of the workpiece setup station with the top cover of the tombstone shown in FIG. 1 opened, and FIG. 10 is an example of the fluid pressure supply circuit for the workpiece clamper. be. 1... stocker, 4... base, 6... pallet, 7... tombstone, 21... swivel base, 24a,
24b...edge locator, 25a-25d...
Work clamper, 40...Plug, 45...Socket, 42...Holder, 43...Socket block, 61...Centering pin, 62...Centering hole, 8
6...High/low pressure switching valve, 90, 90a, 90b
...Accumulator, WSS...Work setup station.

Claims (1)

[Scope of Claims] 1. An automatic workpiece mounting device that uses fluid pressure to attach a workpiece to a workpiece fixture at a workpiece setup station of a machining system, which is positioned and mounted on a machine tool and setup station, or is mounted on a conveyance device. A workpiece mount that can be exchanged between each other and clamp the workpiece on multiple surfaces using a workpiece clamper operated by fluid pressure; A fluid pressure receiving part that engages with a fluid pressure supply part when placed, a plurality of fluid circuits communicating from the fluid pressure receiving part to workpiece clampers on a plurality of surfaces within the workpiece mounting table, and a plurality of fluid circuits provided in the middle of the fluid circuits. , an accumulator that backs up fluid pressure when the workpiece mounting base is moved from the workpiece setup station and the supply of fluid pressure is cut off; An automatic workpiece mounting device equipped with an accumulator disconnection means that cuts off only the fluid circuit leading from the accumulator to the workpiece clamper on its indexed surface. 2. The fluid pressure receiving section includes a plurality of self-sealing pipes that are blocked from fluid when not engaged with the fluid pressure supply section provided on the work setup station, and communicated when engaged with the fluid pressure supply section. An automatic workpiece mounting device according to claim 1, comprising a joint. 3. The automatic workpiece mounting device according to claim 1 or 2, wherein the accumulator is installed commonly for workpiece clampers on all surfaces that can be mounted on the workpiece mounting base. 4. The accumulator intermittent means is configured to provide the same number of on-off valves as the number of workpiece mounting surfaces of the workpiece mounting base in the middle of the fluid circuit leading from the accumulator to the workpiece clampers on each of the workpiece mounting surfaces, and When one surface is indexed, a pin protruding from a predetermined position on the workpiece setup station acts on the opening/closing valve corresponding to the indexed surface of the workpiece mounting base to close it, and when it is removed from the indexing position, the opening/closing valve is closed. An automatic workpiece mounting device according to any one of claims 1 to 3, which is configured such that a valve opens.