JPH0655399A - Workpiece changing device for machine tool - Google Patents

Abstract

PURPOSE:To provide a workpiece changing device capable of replacing machined workpiece with an unmachined workpiece simply at low cost in an automatic machine tool. CONSTITUTION:A workpiece grip hand 22a provided with a workpiece grip claw 23a is held to a tool storage magazine 24 provided at an automatic tool changing device, and this workpiece grip hand 22a is transferred between the tool storage magazine 24 and the main spindle 20 of an NC machine tool. A workpiece W finished with machining is gripped from a work table 14 by the workpiece grip hand 22a and returned to a workpiece conveyor means 40 for performing the carry-in/out of workpieces between the external position of the machine tool and the position above the work table 14. Replacing action of fitting an unmachined workpiece W onto the work table 14 from the workpiece conveyor means 40 is performed under the control of NC system 6 of the machine tool.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work exchanging device for a machine tool, and more particularly to a machined work on a work table of a machine tool by a single control device for controlling the tool exchanging of the machine tool and the work machining operation. The present invention relates to a work exchanging device for a machine tool, which is capable of controlling the exchange action with an unmachined work that is carried in by a work carrying-in means.

[0002]

2. Description of the Related Art N for the purpose of cost reduction of machined products
C For automatic machining and labor saving of workpieces by machine tools,
Automatic tool exchange is performed between the tool changer that has a tool storage magazine that stores a large number of tools through each socket means and the spindle of the machine, and the unmachined work is carried into the work mounting position of the machine tool. In order to promote automation and labor saving, it is possible to perform automatic replacement of a workpiece that carries out a machined workpiece from the workpiece mounting position by various means.

As an automatic work replacement means which has been conventionally used, for example, US Pat.
No. 359,815, a hand equipped at the tip of a robot device integrally equipped with a machine tool, which is used for exchanging a work between a work supply table and a work table, and a predetermined work mounting surface. It has already been proposed that the work can be efficiently replaced regardless of the shape and size of the work by mounting the work on the work table of the machine using a pallet of a fixed shape with Suggested or offered.

[0004]

However, in the case of performing replacement of processed and unprocessed workpieces by using a robot, a multi-axis control (minimum four-axis control) type robot is required. Providing a high-performance robot integrally on the machine side of an NC machine tool increases costs associated with robot manufacturing and requires a control device for multi-axis control, which leads to increased automation costs. As a result, the production cost of the processed product is rather increased in many cases.

On the other hand, the method using a pallet has a drawback that the work of attaching and detaching the work to and from the pallet involves the work of the operator to attach and detach the work, and the work machining cost cannot be sufficiently reduced in the end.

Therefore, the main object of the present invention is to eliminate the problems and drawbacks associated with such conventional automatic work replacement or replacement. Another object of the present invention is to provide a work changing device for a machine tool capable of controlling all of automatic tool changing, work automatic replacing, and work automatic machining using a control device for an NC machine tool. .

[0007]

SUMMARY OF THE INVENTION According to the present invention, a tool storage magazine of an automatic tool changer holds a work hand having a work gripping claw via a tool holder, and the work gripping hand is used as a tool storage magazine. Similar to automatic tool exchange of multiple stored tools, it is detachably attached to the spindle of NC machine tool, and the machined work is grasped from the work table of the machine tool by the work grasping claws of the machine grasping hand. Replacement that returns the processed workpiece to the work transfer means that carries in and out the work between the external position of the machine and the position above the work table, and also transfers the unprocessed work from the work transfer means to the work table. Action, N
The C machine tool is configured to perform the movements in the three-axis (X, Y, Z) directions in the three-dimensional space, and to be performed under the control of the NC device of the machine tool.

That is, according to the present invention, the tool storage magazine provided on the side of the spindle head of the machine tool is held at a predetermined storage position, and the machine tool is held at the tool exchange position in accordance with the linear movement of the spindle head. A work gripping hand, which is detachably attached to the spindle and has a work gripping claw at its tip, and a work gripping claw of the work gripping hand mounted on the spindle of the machine tool described above, are used as a work gripping position and a work releasing position. Between the hand actuator that is operated between the work machine and the upper position of the work table of the machine tool and the outer position of the machine tool, and the work transfer that has the work placement surface at the carry-in end Means, the attachment / detachment action of the work gripping hand performed according to a predetermined tool exchange procedure between the tool storage magazine and the spindle, and the end of the work process of the work. Work exchange between the work placement surface of the work transfer means and the work table, in which the work holding hand attached to the spindle replaces the processed work with the unprocessed work according to a predetermined work replacement procedure. There is provided a work exchanging device for a machine tool, which is provided with a control means for controlling the action.

[0009]

The work gripping hand, which is attached and attached to the tip of the spindle of the machine tool, grips the machined work by the linear motion of the spindle head and the control of the control device, and once holds it from the work table.
The machined work is moved down to the upper position of the work table, and the processed work is lowered and placed in a space on the work placement surface of the work transfer means, and then placed on the work placement surface of the work transfer means. Workpiece replacement is performed by gripping a processed workpiece, retracting it once, and after moving the workpiece conveying means, lowering the unprocessed workpiece to a predetermined workpiece attachment position on the workpiece table. At this time, the work gripping hand is inserted into the spindle, the work gripping claw is opened and closed, the work table is moved in the X-axis direction and the Y-axis direction orthogonal to each other, the spindle head is moved in the Z-axis direction, and the work transfer means is carried in. All carry-out operations are 1
It is controlled under the control device of the table, that is, the NC device. Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.

[0010]

FIG. 1 is a front view of a machine tool having a work changing device in an embodiment in which the present invention is applied to a vertical NC machine tool, and FIG. 2 is a plan view of the machine tool seen from above. Three
1 is a front view similar to FIG. 1 showing the work loading operation of the work transfer means, and FIG. 4 is an enlarged and detailed view of the tool magazine and the work gripping hand inserted at the lower end of the spindle of the machine tool, and the work replacement operation. FIG. 5 is a block diagram including a mechanism diagram showing a signal line of a control system for carrying out the process, FIG. 5 is a schematic view showing an example of the mechanism of the work transfer means, and FIG. 6 is another example of the mechanism of the work transfer means. FIG. 7 is a schematic view showing yet another example of the mechanism of the work transfer means.

1 and 2, the vertical NC machine tool has a base 12, on which a work table 14 is mounted via a well-known saddle and knee, which are orthogonal to each other in a horizontal plane. It is provided so as to be controllably movable by biaxial directions, that is, the X-axis direction and the Y-axis direction by respective drive motors (only the X-axis drive motor Mx appears in the figure, the Y-axis drive motor My does not appear in the figure). These drive motors Mx and My are controlled by the NC device (see FIG. 4), respectively. A column 16 is erected and fixed on the base 12, and the spindle head 1 is attached to the front of the column 16.
8 is provided slidably in the vertical axis (Z axis) direction, and can be moved up and down to a predetermined vertical position according to the operation of the Z axis motor Mz. A spindle 20 is supported by the spindle head 18 so as to be rotatable about the axis of the vertical axis, and is rotationally driven by a spindle motor Ms. Various processing tools 22 are detachably attached to the tip of the main shaft 20.

On the other hand, in front of the column 16, a tool storage magazine 24 of an automatic tool changer is provided in an inclined arrangement via a supporting means and is also rotatable about the axis of rotation for indexing. The tool storage magazine 24 stores a plurality of processing tools via a tool holder, and is swingably provided between an inclined retracted position and a tool exchange position that is close to immediately below the spindle 20, and the latter. When it is placed in the tool exchange position, the desired one of the stored tools or the empty tool storage section can be indexed to the position directly below the lower end of the spindle 20 in accordance with the automatic tool exchange command. ing.

The machine body of this vertical NC machine tool has a structure surrounded by a splash cover 26 which prevents scattering of machining fluid and cutting chips, and a control operation panel 28 is provided on one side surface thereof. There is. An electric control box 16a is provided on the back surface of the column 16.

A clamp jig 30 for fixing and holding a workpiece to be machined is mounted on the work table 14 described above, and the machining tools 22 attached to the tip of the spindle 20.
Is lowered by the Z-axis operation of the spindle head 18 and the clamp jig 3
When a machining position approaching the workpiece fixed at 0 is reached and the spindle 20 is rotated by the spindle motor Ms, the machining operation is performed. Further, when the predetermined processing steps are completed, the processing position is raised to the retracted position or the automatic tool changing position as required.

Work transfer means 40 is provided on the side of the machine body of the machine tool.
Inside the machine, it is provided so as to be movable in both a direction toward the inside of the machine as shown by an arrow T and a direction of retracting from the inside of the machine to the outside of the machine shown in FIG. 1, and as shown in FIG. A predetermined positioning displacement is provided by an actuator such as an air cylinder device in a direction shown by an arrow S orthogonal to the direction, and a plurality of them are provided in the upper surface region on the tip side toward the inside of the machine tool when viewed in the transport direction T. When the workpieces W are mounted, and the workpieces W are unprocessed workpieces, they can be conveyed toward the inside of the machine body, and the processed workpieces can be received inside the machine body and carried out to the outside of the machine body. There is. Although a specific structure of the transfer mechanism of the work transfer means will be described later, the transfer operation of the work W will be briefly described with reference to FIG.

As shown in FIG. 3, the work transfer means 40 comprises transfer plates 41, 42 and 43 having a three-stage structure.
Is a fixed plate and is attached to the pedestal 44 that can be positioned and displaced in the direction indicated by the arrow S described above. With respect to the fixed carrier plate 41, the carrier plate 42 is directed toward the inside of the machine body of the machine tool.
Is provided so as to be able to carry and move the first stage.
On the other hand, the carrier plate 43 has a structure capable of further carrying and moving to the inside of the machine in the second stage. W is placed and the unprocessed work W is conveyed to the upper region of the clamp jig 30 on the work table 14, and the processed work W held by the clamp jig 30 is received and carried out of the machine body. To do. In addition, in FIG. 2, three unprocessed works W are placed on the carrying plate 43 of the work carrying means 40, and three empty spaces We for receiving the works shown by the three dotted lines are secured. On the other hand, a state is shown in which the three workpieces W are held in the clamp jig 30 of the work table 14 in the process-finished or processed state.

Here, referring to FIG. 4, a tool storage magazine 24 is provided in front of the spindle head 18 at the above-described tilted position which is tilted downward, and is supported by a part of the column 16 by a magazine support 36 and shakes. It is possible to swing about the dynamic fulcrum 38 as indicated by an arrow U and to be able to perform indexing rotation as indicated by an arrow V.

A spindle 2 rotatably supported by a spindle head 18.
No. 0 has an indexing gear 50 at its lower end, and when the spindle 20 moves up together with the spindle head 18 by the operation of the Z-axis motor Mz, and the gear 50 meshes with the indexing gear 52 of the tool storage magazine 24, These indexing gears 5 according to the rotation of 20
The tool storage magazine 24 shows an arrow V through the meshing of 0 and 52.
The index rotation shown in is performed. At the same time, the tool storage magazine 24 swings in the direction indicated by the arrow U in response to the ascending action of the spindle head 18 via a cam mechanism not shown in the drawing, and moves between the position directly below the spindle 20 and the illustrated retracted position. It can be moved with. The structure and operation of an automatic tool changer equipped with this type of tool storage magazine is already well known, and a further explanation is omitted here.

As a basic constituent feature of the present invention, the work holding hand 22a is stored in the tool storage hole of the tool storage magazine 24 via the tool holder, and the lower end of the spindle 20 is operated by the automatic tool changing action. It can be inserted into the tool insertion hole of. FIG. 4 shows the work gripping hand 2 that is transferred from the tool storage magazine 24 to the lower end of the spindle 20 and is inserted into the work gripping hand 2.
2a is shown. When the work gripping hand 22a is inserted into or removed from the tool insertion hole, a well-known drawbar mechanism provided inside the spindle 20 dissociates or separates the tool holder portion of the work gripping hand 22a in accordance with the vertical movement of the spindle head 18. It is achieved by grasping.

In the present embodiment, the work gripping hand 22a is formed as an air-operated air chuck device, and the work gripping claw 23a composed of a known three-claw mechanism is
It has a structure for gripping the work W by expanding or contracting by pneumatic operation. Therefore, an air supply unit 54 for supplying pressurized air is provided at the lower end of the main shaft 20, and when the work gripping hand 22a is inserted into the tool insertion hole of the main shaft 20, the air supply unit 54 is supplied with the pressure air. When they are supplied, the two are brought into close contact with each other via an appropriate air suction device, pressure air is supplied from the air supply unit 54 to the work gripping hand 22a, and the work gripping claw 23a of the three-claw mechanism is expanded or By causing the contraction, the work gripping claw 23a can grip the outer diameter of the work W or the inner diameter in the case of the hollow work W.

As shown, the air supply unit 54 includes an air source 61 such as an external air compressor and a filter 62.
The pressure air supplied via the solenoid valve means 63 is supplied to the main shaft end air supply source 64, is held, and is further supplied from here via the air pipe line 65. At this time, The opening and closing actions of the solenoid valve means 63 are activated in response to a command signal sent from the NC control device 60 of the NC machine tool, and therefore the work gripping claw 23 of the work gripping claw hand 22a is responsive to the command signal.
The opening and closing of a is performed.

The NC device 60, of course, has a structure for instructing the operation of the automatic tool changing device of the NC machine tool, that is, the swinging action and the indexing rotation of the tool storage magazine 24 via the machine body. Further, the automatic machining action by the machining tools 22 inserted in the tool insertion hole at the tip of the spindle 20, the feeding operation of the work table 14 in the X and Y axis directions, and the Z of the spindle head 18 are performed.
Axial movements are controlled according to numerical control data.

Now, the work transfer means 40 already described here.
An example of the operation mechanism of the movable transfer plates 42 and 43 with respect to the fixed transfer plate 41 will be described with reference to FIGS. 5 (a) and 5 (b). Referring to FIG. 5A, the present embodiment shows an example of the work transfer means 40 using a pinion rack mechanism. That is, the fixed transport plate 41 fixed to the pedestal 44
Rack teeth 41a are machined on the upper surface of the pin, and a pinion 42a is rotatably provided around a horizontal axis on the movable carrier plate 42 of the first stage in mesh with the rack teeth 41a of the fixed carrier plate 41. The pinion 42a is provided so as to mesh with rack teeth 43a formed on the lower surface side of the second-stage movable transport plate 43. A drive motor including a servo motor or the like is provided on the opposite side of the pinion 42a to the movable transfer plate 42 of the first stage, and the operation of the drive motor is controlled by the NC device 60 shown in FIG. 42a is rotationally driven to generate and control the linear movement T1 of the first-stage conveyance plate 42 and the linear movement T2 of the second-stage movable conveyance plate 43 with respect to the fixed conveyance plate 41. A mounting surface on which the work W is mounted is provided on the upper surface of the leading end region of the latter movable transport plate 43.

Here, referring to FIG. 5B, the movable carrier plates 4 in the first and second stages with respect to the fixed carrier plate 41.
2 and 43 show the state in which they are conveyed and moved toward the front, that is, toward the inside of the machine tool, and a plurality of limit switches LM1 to LM3 provided on the movable carrier plate 42 are provided on the fixed carrier plate 41. By engaging with the dog D1, it is configured so that it can be detected whether or not the work W placed on the movable transport plate 43 has reached a predetermined position inside the machine, and these limit switches LM1 to LM3. By feeding back the signal of (1), the moving amount of the movable transfer plates 42, 43 can be controlled.

FIG. 6 shows the fixed transfer plate 4 of the work transfer means 40.
2 shows another embodiment of the transfer movement mechanism of the movable transfer plates 42 and 43 for No. 1, and in this example, two fluid cylinder devices 71 are used instead of the transfer movement mechanism by the pinion rack mechanism and the servo motor described above. , 72 is used. That is, the tip of the movable rod 71a of the fluid cylinder device 71 fixed to the upper surface of the fixed transfer plate 41 is fixed to the lower surface in front of the movable transfer plate 42 of the first step, while being fixed to the upper surface of the movable transfer plate 42 of the first step. Fluid cylinder device 72
The movable rod 72a is fixed to the lower surface of the second-stage movable transport plate 43. As a result, it is possible to control the transport movement of both movable transport plates 42 and 43 in accordance with the expansion and contraction of the movable rods 71a and 72a of both fluid cylinder devices 71 and 72, respectively. If the operations of these fluid cylinder devices 71 and 72 are controlled by the NC device 60 described above, it is possible to control the work loading and unloading operations by the work transporting means 40.

FIG. 6A shows a fluid cylinder device 71, 7.
2 are both in the retracted position and therefore the movable carrier plates 42, 43
Indicates a state where the machine tool is retracted outside the machine body.
Further, in FIG. 6B, both cylinder devices 71 and 72 are extended so that the work table 14 (see FIG.
(Refer to FIG. 3) and to a position below the lower end of the main shaft 20. In this case, by controlling the amount of extension of the movable rods 71a, 72a due to the fluid pressure of both cylinder devices 71, 72, it is possible to achieve the control of the amount of transfer movement, and therefore the limit switches and dogs of the above-described embodiment can be achieved. It does not need to be provided.

FIG. 7 shows a case in which a known chain mechanism is applied as still another embodiment of the work transfer means 40. In this embodiment, a chain 73 wound around a pair of sprockets 75a and 75b provided on the side of the fixed conveying plate 41 is connected by a connecting member 78 to the movable conveying plate 4 of the first stage.
It has a structure in which the movable carrier plate 42 of the first stage is moved forward and backward in accordance with the rotation of the chain 73 by being connected to the two and driving the same sprockets 75a and 75b by a drive motor 76 composed of a servo motor.

Similarly, a chain 74 wound around a pair of sprockets 77a, 77b provided on the side of the first-stage movable transport plate 42 is connected to the second-stage movable transport plate 43 by a connecting member 79. , The same sprocket 77a, 77b is driven by a drive motor 78 which is a servo motor, so that the second stage movable transport plate 4 is moved in accordance with the rotation of the chain 74.
It has a configuration for moving the 3 forward and backward. In the case of the present embodiment, a plurality of dogs 81a, 81b, 81c and the like provided on the lower surface of the second-stage movable transport plate 43 are controlled by the limit switch 80 provided at the tip of the first-stage movable transport plate 42. Is configured to be able to detect a carry-in movement amount when the work W is carried into the inside of the machine.

By displacing the gantry 44 of the work transfer means 40 described above between two positions in the direction perpendicular to the transfer direction (direction of arrow S in FIG. 2), the movable transfer is performed inside the machine body of the machine tool. As described above, the means for positioning either the work W placed on the plate 43 or the empty position We to the position directly below the work gripping hand 22a inserted into the spindle 20 is a suitable fluid cylinder device. By using the same, the supply of the same fluid pressure (pressure air) may be controlled by the NC device 60 of the machine tool.

However, the pedestal 4 for this positioning
As a moving means of No. 4, a conveyor line is installed inside the machine body of the machine tool, the conveyor line is laid in a direction corresponding to the moving displacement direction S (FIG. 2) of the gantry 44, and on the work table 14 or its upper part. Clamp jig 3 attached
0 and the fluid cylinder device described above by displacing the pedestal 44 along the conveyor line via a feed screw mechanism using a drive motor such as a servo motor as a driving means. It may be configured to impart a similar positioning action.

The operation of the work exchanging device for a machine tool of the present embodiment having the above-mentioned structure will be described below. First, when the NC machine tool is used to automatically machine the unprocessed workpieces W, a plurality of unprocessed workpieces W are preliminarily placed on the workpiece transfer means 40.
And a vacant space We for receiving the already processed workpiece W are secured.

Then, when the machining of the workpiece W held by the clamp jig 30 on the work table 14 by the machining tool 22 inserted into the spindle 20 of the machine tool is finished, the spindle 20 is once raised. Move away from the processed work W on the clamp jig 30. Next, the operation for exchanging the processed work W with the unprocessed work W of the work transfer means 40 is started.

At this time, first, the work gripping hand 2 stored in the tool storage magazine 24 of the automatic tool changing device.
The machining tool 2 inserted into the tool insertion hole of the spindle 20 by performing automatic tool exchange action on the 2a according to the M command of the NC device 60.
Replace with 2. As a result, the work gripping hand 22a is attached to the lower end of the spindle 20.

Next, the spindle 20 is lowered along with the spindle head 18 by the Z-axis operation, and is moved to directly above the machined work W held by the clamp jig 30 after the machining is completed. At this point, pressure air is supplied from the air supply unit 54 to the work gripping hand 22a so that the work can be gripped. Further, the work gripping hand 22a is lowered to grip the processed work W. At this time, the gripping of the work W by the clamp jig 30 is released, and the work W is transferred to the work gripping hand 22a.

When the gripping of the machined workpiece W by the workpiece gripping hand 22a is completed, the spindle head 18 and the spindle 2 are
0 to raise the processed work W to the work gripping hand 2
It is gripped by 2a and is made to stand by in the area above the clamp jig 30. At this point, the side door of the splash guard 26 is opened and the work transfer means 40 prepares for loading the unprocessed work W.

On the other hand, in the work transfer means 40, the positioning displacement in the direction of arrow S in FIG. 2 is performed so that the space We on the upper surface of the second-stage movable transfer plate 43 can be aligned with the axis of the main shaft 20. After that, the upper position of the work table 14 inside the machine advances. In this way, the processed work W gripped by the work gripping hand 22a is used as the spindle head 1
8 and the main shaft 20 are moved downward in the Z-axis direction, and the space We on the upper surface of the movable transfer plate 43 of the work transfer means 40 is set to 1
Then, lower the same processed workpiece W. At this time, the gripping operation by the work gripping claw 23a of the work gripping hand 22a is released.

Next, the work gripping hand 22a is retracted to the upper position again in accordance with the upward movement of the spindle head 18 and the spindle 20 in the Z-axis direction. At the same time, the workpiece transfer means 40 causes the unprocessed workpiece W on the movable transfer plate 43 to reach the position directly below the spindle 20 by the positioning displacement in the arrow S direction. Thus, again, the unmoved workpiece W is received from the workpiece conveying means 40 by the workpiece gripping hand 22a by the downward movement of the spindle head 18 and the spindle 20. Then, the work gripping hand 22
Retract upward while holding it at a.

When the retraction of the unprocessed work W held by the work holding hand 22a is completed, the work transfer means 40
Is carried out to the outside of the machine body of the machine tool. This allows
The processed work W previously placed on the movable transport plate 43 of the means 40 is carried out of the machine.

Inside the machine, the workpiece gripping hand 22a descends by the downward movement of the spindle head 18 and the spindle 20 in the Z-axis direction, and the uncut workpiece W grasped and held is emptied on the work table 14 by the clamp jig 30. Lower the same unprocessed work W to
The work gripping claw 23a is released and the work W is placed on the clamp jig 30.

At this time, the clamp jig 30 performs the clamping operation from the open state to the clamp closed state to hold the work W in the clamped state. Thus unprocessed workpiece W
When the workpiece is gripped by the clamp jig 30 of the work table 14, the work exchange between the processed work W and the unprocessed work W is completed. Therefore, the work gripping hand 22a inserted into the lower end of the spindle 20 is replaced with the desired machining tool 22 again by the automatic tool changing action, and is returned to the tool storage magazine 24. Then, after that, the machining tool 22 inserted into the spindle 20 automatically performs machining on the unmachined work W according to the NC program.

As shown in FIG. 2, when a plurality of works W are gripped by the clamp jig 30 on the work table 14 and all the works W are completed,
When replacing the unprocessed work W carried in by the work transfer means 40, the above-mentioned single processed work W is used.
By repeating the process of exchanging a single unprocessed work W with, a plurality of unprocessed works W can be loaded into the clamp jig 30 on the work table 14 again, and automatic processing can be sequentially performed. .

In the above description, the work transfer means 40
And the operation timing of the spindle head 18 and the spindle 20 is one NC
It goes without saying that all operations are programmed in the device so that they can be performed at appropriate timing.

[0043]

As can be understood from the above description of the embodiments, the present invention stores the work holding hand having the work holding claws in the tool storage magazine of the automatic tool changer via the tool holder. The work gripping hand is removably attached to the spindle of the NC machine tool in the same manner as automatic tool change of a plurality of tools stored in the tool storage magazine, and the work table of the machine tool is held by the work gripping claw of the work gripping hand. Take the processed work from the upper clamp jig,
The machined work is returned to the work transfer means for carrying in and out the work between the external position of the machine tool and the position above the work table, and the unprocessed work is received from the work transfer means to receive the work on the work table. The displacement operation to be attached to the clamp jig is configured to be performed by using the operation of the NC machine tool in the three-axis (X, Y, Z) directions in the three-dimensional space and under the control of the NC device of the machine tool. Therefore, by operating the NC machine tool at all times, it is possible to perform unmanned operation for exchanging a machined work and a non-machined work as part of automatic machining or automatic tool machining. The effect is that it can be operated and the work can be exchanged.

Further, in the present invention, it is only necessary to store the work-holding hand in which the tool can be exchanged in the same manner as the machining tool in the tool storage magazine, and the work transfer means is also provided with a simple transfer mechanism, which is an NC device. Since the operation can be controlled, the work changing device can be obtained at a very low cost. Furthermore, when the work is exchanged by the conventional multi-axis robot, the load capacity of the robot is limited, but as in the present invention, the structure is such that it is gripped by an air-operated three-claw type hand. Then, by adjusting and controlling the gripping force of the gripping claws of the hand with the air pressure, it is possible to obtain the effect of relaxing the limitation due to the weight of the work.

Although the above-described embodiment shows an example in which the present invention is applied to a vertical NC machine tool, it goes without saying that a horizontal N machine in which the Z-axis motion of the main spindle is similarly performed in the horizontal direction.
Those skilled in the art can easily understand that even a C machine tool can be realized by applying a completely similar configuration. Further, it goes without saying that various driving means and the like in the work exchanging device of the present invention can be modified in various ways such as performing the above fluid-operated type by a servomotor.

[Brief description of drawings]

FIG. 1 is a front view of a machine tool including a work changing device in an embodiment in which the present invention is applied to a vertical NC machine tool.

FIG. 2 is a plan view of the machine tool seen from above.

FIG. 3 is a front view similar to FIG. 1, showing a work carrying-in operation of the work carrying means.

FIG. 4 is a block diagram including a mechanism diagram showing an enlarged and detailed view of a tool magazine and a work gripping hand attached to a lower end of a spindle of a machine tool, and a signal line of a control system for performing a work replacement operation. Is.

FIG. 5 is a schematic view showing an example of a mechanism of a work transfer means.

FIG. 6 is a schematic view showing another example of the mechanism of the work transfer means.

FIG. 7 is a schematic view showing still another example of the mechanism of the work transfer means.

[Explanation of symbols]

 12 ... Base 14 ... Work table 16 ... Column 18 ... Spindle head 20 ... Spindle 22 ... Machining tool 22a ... Work gripping hand 23a ... Work gripping claw 24 ... Tool storage magazine 30 ... Clamp jig 40 ... Work transfer means 41 ... Fixed transfer Plate 42 ... Movable transport plate 43 ... Movable transport plate 44 ... Frame 54 ... Air supply unit 60 ... NC device

Claims (1)

[Claims] 1. A tool storage magazine provided on a side of a spindle head of a machine tool, which is held at a predetermined storage position and is detachably attached to a spindle of a machine tool according to a linear movement of the spindle head at a tool exchange position. A work gripping hand that is provided so that it has a work gripping claw at its tip, and a hand actuator that operates the work gripping claw of the work gripping hand attached to the spindle of the machine tool between a work gripping position and a work releasing position. And a work transfer means provided with a work placement surface at a loading end and capable of loading and unloading a work between an upper position of a work table of a machine tool and an external position of the machine tool, and the tool storage According to a predetermined tool exchange procedure between the magazine and the spindle, the attachment / detachment action of the work gripping hand, and the movement of the work transfer means in response to the end of the work process of the work. Between the work mounting surface and the work table, the work exchanging action of performing the replacement of the machined work and the unmachined work by the work gripping hand attached to the spindle according to a predetermined work replacement procedure is controlled. A workpiece exchange device for a machine tool, comprising: a control means.