JPH05192839A - Tool exchanger - Google Patents

Abstract

PURPOSE:To simplify a structure for automatically and manually controlling in synchronization with the motion of a tool exchange arm the supply and discharge of a pressure fluid to and from a cylinder for tightening and loosening a tool unclamping device, in a device for exchanging tools between a main spindle and a tool magazine by use of a cam mechanism to cause the tool exchange arm to advance and retreat and make rotary motion in the normal and reverse directions at predetermined angles. CONSTITUTION:A directional control valve 64 which is capable of being manually switched is provided for controlling the supply and discharge of a pressure fluid to and from a cylinder 33 which tightens and loosens against a main spindle a tool mounted on the main spindle. The tool exchanger is provided with a lever 61 for automatically switching the directional control valve 64 and a first and a second cam follower 60A, 60B for controlling the supply and discharge of the pressure fluid to and from the tightening/loosening cylinder 33 by means of operation of the lever 61 in synchronization with the advance and retreat and the normal and reverse rotary motion at predetermined angles of a change arm shaft are provided on the cam shaft of a cam mechanism which causes the tool change arm to advance and retreat and to make rotary motion in the normal and reverse directions at predetermined angles.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tool changing device for machine tools.

[0002]

2. Description of the Related Art In a machining center or the like, between a main shaft and a tool magazine, a cam shaft for rotating an exchange arm shaft parallel to these shafts by a cam driving motor, and a cam provided on the cam shaft. The cam mechanism is configured to move forward and backward and rotate forward and backward at a predetermined angle, and a tool exchanging arm for exchanging a tool between the spindle and the tool magazine is arranged, and a tightening and loosening cylinder of a tool clamp device provided on the spindle is arranged. For example, Japanese Patent Application Laid-Open No. 62-228840 provides a tool changing device which controls the operation in synchronization with forward and backward movements of the tool changing arm and forward and reverse rotational movements of a predetermined angle.

The forward / backward movement of the tool exchanging arm and the forward / reverse rotational movement of a predetermined angle in the tool exchanging device of this type are
When the tool is replaced with the standby position avoiding a predetermined angle from the spindle and the exchange position as the original position, the tool and the magazine of the spindle and the tool magazine are gripped by the tool exchange arm by 90 ° from the predetermined angle, and the tool is moved forward in the axial direction. A series of tools are removed by removing both the spindle and the tool magazine, rotating them by 180 ° and exchanging both tools, retreating in the axial direction to attach the tools to the spindle and the tool magazine respectively, and reversing 90 ° to return to the original position. It is an action.

In this type of tool exchanging device, in order to shorten the tool exchanging time, when a tool is removed from the spindle, the unclamping cylinder is actuated prior to the exchanging of the tool so that the clamping disc spring is clamped in the clamping direction. After the force is loosened and the tool of the main shaft is gripped by the tool changing arm, the tool is unclamped only by operating the tightening and loosening cylinder.

[0005]

In the above-mentioned conventional tool changing device, the means for controlling the operation of the tightening / loosening cylinder of the tool clamping device in synchronization with the forward / backward movement of the tool changing arm and the forward / reverse rotational movement of a predetermined angle. A swing lever that engages with a cam groove of a cam mechanism to swing, a shaft that is rotated by the swing lever, an operating lever that is fixed to the shaft, and a mechanical valve that is operated by the operating lever. Because it is configured, if you do not rotate the cam
The mechanical valve cannot be switched. When the tool is manually replaced, the tightening / loosening cylinder cannot be operated unless another manual switching valve is provided in the same circuit as the mechanical valve, resulting in a complicated structure and high cost.

It is an object of the present invention to provide a tool changing device in which a tightening and loosening cylinder of a tool clamping device can be manually and automatically switched by a single switching valve.

[0007]

SUMMARY OF THE INVENTION A feature of the present invention that achieves the above object is to provide a camshaft in which an exchange arm shaft parallel to the main shaft is rotated by a cam drive motor between the main shaft and a tool magazine. And a tool exchanging arm for exchanging the tool between the spindle and the tool magazine by moving the tool forward and backward and rotating forward and backward at a predetermined angle by a cam mechanism composed of a cam provided on the cam shaft. In a tool exchanging device including a tool clamping device and an unclamping device composed of a tightening / loosening cylinder of the tool clamping device, a manually switchable switch for supplying / discharging a pressure fluid to / from the tightening / loosening cylinder. A valve, a lever for automatically switching the switching valve, and a forward / backward movement of the exchange arm shaft on the cam shaft of the cam mechanism and a forward / reverse rotational movement of a predetermined angle in synchronization with the forward / backward movement. Operating the bar with an angle retardation to supply and discharge control pressure fluid to the clamping loosening cylinder is obtained by a pair of cam members which project.

[0008]

With the above construction, the lever is actuated by the cam member at the rotation angle of the cam shaft of the cam mechanism for moving the exchange arm shaft forward and backward and rotating forward and backward by a predetermined angle, and the switching valve is automatically switched so that the tool clamping device is operated. Enables proper operation control of the tightening / loosening cylinder at the required turning angle position of the tool change arm, and manually switches the switching valve when manually changing the tool to operate the tightening / loosening cylinder of the tool clamping device. Is made possible.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a drive mechanism of a tool changing arm. This Figure 1
In the above, reference numeral 1 is a housing of the drive mechanism, and the exchange arm central shaft 2 is rotatably supported so as to be movable back and forth in the axial direction. A tool exchanging arm is attached to the exchanging arm central shaft 2. Reference numeral 3 denotes a cam shaft, which is rotatably supported in the housing 1 about an axis orthogonal to the axis of the exchange arm central axis 2, and one end of which is connected to an arm drive motor 4.

A disk-shaped cam member 5 is fixed to the cam shaft 3. The cam shaft 3 is provided on one end surface of the cam member 5.
Is provided with a cam groove 5a for advancing and retracting the exchange arm central axis 2 in the axial direction, and the exchange arm central axis 2 is 90 ° and 180 ° on the outer peripheral surface of the cam member 5.
There is provided a roller gear cam 5b that rotates forward and backward at an angle of.

Reference numeral 6 is a revolving arm for advancing and retracting the exchange arm. The pivot arm 6 is pivotally supported at its one end on the housing 1 by a support shaft 7 so as to be pivotable about an axis parallel to the cam shaft 3. The swivel arm 6 has a first engaging roller 6a that engages with the cam groove 5a of the cam member 5.
And a second engagement roller 6b which engages with the annular groove 2a formed on the outer peripheral surface of the exchange arm central shaft 2.

Numeral 8 indicates a housing 1 in the axial direction parallel to the exchange arm central axis 2 in the vicinity of the outer peripheral surface of the cam member 5.
It is a rotary shaft that is rotatably supported by. The rotary shaft 8 is provided with a roller gear 9 meshing with the roller gear cam 5b. A drive gear 10 is fixedly mounted on the rotary shaft 8. Reference numeral 11 denotes an intermediate gear 11 that meshes with the drive gear 10, and this intermediate gear 11 meshes with a driven gear 12 that is fixed to the exchange arm central shaft 2.

5 and 6 are sectional views of the spindle head 20 side, FIG. 5 shows the front end portion of the spindle 21, and FIG.
1 shows the rear end portion of FIG. In FIG. 5, a tool holder 2 is provided at the front end of a spindle 21 rotatably supported by a spindle head 20.
A tapered hole 22 into which the tapered shank No. 3 is fitted is formed. Further, inside the main shaft 21 behind the tapered hole 22, there is a grip claw 25 that engages with and disengages from a pull stud 24 projectingly provided at the rear end of the tool holder 23. A draw bar 26 that expands and contracts the claw 25 is vertically penetrated so as to be able to advance and retract in the axial direction.

The draw bar 26 is constantly urged in the backward direction by a clamping spring 27 such as a disc spring, and the gripping claw 25 is contracted to grip the pull stud 24 of the tool holder 23 and the taper shank of the tool holder 23. Spindle 2
The taper hole 22 of No. 1 is pulled to be in a clamped state.
In addition, in FIG. 5, 16 shows a tool exchange arm.

In FIG. 6, 29 is a clamp spring 2 which is axially movably fitted to the rear end of the draw bar 26.
7 is a spring receiving member, and its retracted end abuts on a locking member 30 screwed to the rear end of the draw bar 26 and is regulated. Reference numeral 31 is the unclamping device main body. The unclamping device main body 31 includes an unclamping cylinder 32.
And a tightening / loosening cylinder 33 are arranged coaxially with the drawbar 26 and mounted on the spindle head 20.

A piston 34 is slidably fitted in the unclamp cylinder 32 so as to be slidable in the axial direction.
A cylindrical body 50 is coupled to the inner peripheral surface of 4, and a pushing member 51 is coupled to the front end surface of the cylindrical body 50. That is, the piston 34, the cylindrical body 50, and the pushing member 51 are integrated. The front end surface 51a of the pushing member 51 has a slight gap between it and the rear end surface 29a of the spring receiving member 29,
Moreover, they face each other so that they can come into contact with each other.

A piston 35 is axially slidably fitted in the tightening / loosening cylinder 33. The operating rod 52 is vertically penetrated through the axial center of the piston 35, a screw 52 provided at the rear end thereof is screwed into the piston 35, and a lock nut 52a is screwed into the screw 52 to integrally form the piston 35 and the operating rod 52. Is bound to. An engaging member 6 is screwed onto the tip of the operating rod 2. The engaging member 36 is engaged with the locking member 30 screwed to the rear end of the draw bar 26 with a slight gap in the axial direction.

The tightening / loosening cylinder 33 has a switching valve 6 to be described later, which is switch-controlled by the rotation angle of the cam shaft 3.
4 (see FIG. 4), it has a port A1 for moving the piston 35 backward by introducing pressure oil, and a port B1 for moving the piston 35 forward.

As shown in FIG. 4, the switching valve 64 is arranged in the pressure fluid supply / discharge circuit for the ports A1 and B1 of the tightening / loosening cylinder 33, and can be manually switched by the manual lever 65. Also, the lever 61 and the link 63
Thus, the rotation angle of the cam shaft 3 can be automatically switched.

As shown in FIGS. 1 to 3, the automatic switching mechanism of the switching valve 64 has a first cam follower 60A at two different radial positions on the surface of the cam member 5 opposite to the cam groove 5a. A second cam follower 60B is provided so as to project on the circumference with a required angular phase difference, and the lever 61 contacts the first and second cam followers 60A and 60B and swings the lever 61 of the drive mechanism. Support shaft 6 for housing 1
It is a structure in which the link 63 is pivotally supported via 2, and the link 63 is fixedly attached to the support shaft 62 and is linked to the switching valve 64.

When the lever 61 comes into contact with the first cam follower 60A as shown in FIG. 2 due to the rotation of the cam member 5, the lever 61 pivots inward in the direction of the axis of rotation, and is brought into the port B1 of the tightening / loosening cylinder 33. Switching valve 6 to supply pressure fluid
4 and the second cam follower 60B as shown in FIG.
When it comes into contact with, the switch valve 64 is switched so as to swivel outward away from the rotation axis and supply the pressure fluid to the port A1 of the tightening / loosening cylinder 33.

The tip of the lever 61 has a downwardly inclined surface 61a for smoothing the ride on the first cam follower 60A, and an upwardly inclined surface 61b for smoothly getting on and off the second cam follower 60B. Is preferably formed. Further, the switching valve 64 is held by a not-shown notch so as to have a moderation at the switching position, and is not moved unless an external force acts. Therefore,
The lever 61 rides on the first and second cam followers 60A and 60B and is held in the lowered position.

In the range where the lever 61 is not in contact with the first and second cam followers 60A and 60B,
The switching valve 64 can be manually switched by the manual lever 65.

Next, the operation of the present invention will be described. The operation of the tool changing arm 16 is, as shown in FIG. 7, that the cam shaft 3 makes one rotation (0 to 360 °), thereby turning 90 °, 180 °, 90 ° from the original position as shown by line a, and , B
It moves forward and backward like the line. By the initial turning of 90 °, one end of the tool changing arm 16 holds the tool holder on the tool magazine side, and the other end holds the tool holder 23 on the spindle 21 side.

The piston 3 of the unclamping cylinder 32 at the time when the tool changing arm 16 starts to rotate 90 °.
4 is moved forward, the pushing member 51 is moved forward through the tubular body 50, and the front end surface 51a of the pushing member 51 pushes the rear end surface 29a of the spring receiving member 29. As a result, the clamping spring 27 is compressed to loosen the tensile force, and the tool holder 23 mounted on the spindle 21 is unclamped. The tool holder 23 holds the unclamped tool holder 23. Even if the tool holder 23 is unclamped, the drawbar 26 has the engaging member 36 engaged with the locking member 30, so that the spindle 21 of the tool holder 23 is not locked.
Dropout has been prevented.

After that, the tool changing arm 16 is moved forward as shown by b1 in FIG. 7B to extract the tool holder from the tool magazine and the spindle 21. At time C1 before the start of the forward movement, the lever 61 contacts the second cam follower 60B at the rotation angle of the cam shaft 3, and the switching valve 64 is switched to supply the pressure oil to the port B1 of the tightening / loosening cylinder 33. As a result, the piston 35 of the tightening / loosening cylinder 33 moves forward, the engaging member 36 contacts the locking member 30 to move the draw bar 26 forward, and the gripping claw 25 expands and the pull stud 24 is pushed. The tool holder 23 is moved to release the bite between the taper shank of the tool holder 23 and the taper hole 22 of the main shaft 21 to smoothly extract the tool holder 23.

After the forward movement of the tool exchanging arm 16 is completed, the tool exchanging arm 16 is swiveled 180 ° and the tool exchanging is performed between the tool magazine and the spindle 21. After turning 180 degrees of the tool changing arm 16, the tool holder is inserted into the tool magazine and the spindle 21 by retreating movement b2. At the time point C2 when the retreat end of the tool changing arm 16 is completed, the lever 61 contacts the first cam follower 60A at the rotation angle of the cam shaft 3 and the switching valve 64 closes the port A1 of the tightening / loosening cylinder 33.
The draw bar 26 is moved backward and the grip claw 25 is closed to grip the pull stud 24.

After that, the piston 34 of the clamping cylinder 32 is moved backward, and the pushing motion of the spring receiving member 29 by the pushing member 51 is released to transmit the force of the clamping spring 27 to the draw bar 26 via the locking member 30. Then, the tool holder 23 is attracted to the tapered hole 22 of the main shaft 21 via the grip claws 25 and clamped. During this clamping operation, the tool change arm 16 is rotated 90 ° and returned to the original position. In this original position, the lever 61 is separated from the first and second cam followers 60A and 60B, so that the switching valve 64 can be freely switched by manual operation. Therefore, when the tools are replaced manually, the switching valve 64 is switched by the manual operation of the manual lever 65, and the tightening / loosening cylinder 33 is operated.

[0029]

As described above, according to the present invention, a manually switchable switching valve for controlling the supply and discharge of pressure fluid is provided in a cylinder that tightens and loosens a tool mounted on the spindle with respect to the spindle. A lever for automatically switching and a tool exchange arm for exchanging a tool between a spindle and a tool magazine are moved forward and backward, and forward and backward and forward and backward of the exchange arm shaft on a cam shaft of a cam mechanism for rotating forward and backward at a predetermined angle. A structure provided with a pair of cam members projecting with an angular phase difference in order to control the supply and discharge of pressure fluid to the tightening and loosening cylinder by operating the lever in synchronization with the forward and reverse rotational movement of the angle. Therefore, it is possible to perform automatic and manual switching control of pressure fluid supply / discharge to / from the tightening / loosening cylinder with one switching valve, the valve switching operation structure is simplified, and cost reduction is obtained.

[Brief description of drawings]

FIG. 1 is a sectional view of a cam mechanism showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram of the operation of the main part of the present invention.

FIG. 3 is an explanatory diagram of the operation of the main part of the present invention.

FIG. 4 is a schematic view of a main part of the present invention.

FIG. 5 is a sectional view of the tip of the spindle.

FIG. 6 is a sectional view of the rear end portion of the spindle.

FIG. 7 is a diagram of a tool changing arm turning and advancing / retreating operation with respect to rotation of a cam shaft

[Explanation of symbols]

 1 Housing 2 Replacement Arm Center Shaft 3 Cam Shaft 4 Cam Drive Motor 5 Cam Member 5a Cam Groove 5b Roller Gear Cam 6 Swivel Arm 8 Rotation Shaft 9 Roller Gear 10 Drive Gear 11 Intermediate Gear 12 Driven Gear 20 Spindle Head 21 Spindle 26 Drawbar 27 For Clamping Spring 31 Tool unclamping device 32 Unclamping cylinder 33 Tightening and loosening cylinder 60A 1st cam follower 60B 2nd cam follower 61 Lever 63 Link 64 Switching valve 65 Manual lever

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masuhiro Yasuda 1-1, Asahi-cho, Kariya city, Aichi Toyota Koki Co., Ltd.

Claims (1)

[Claims] 1. A cam mechanism comprising a cam shaft for rotating a replacement arm shaft parallel to the main shaft by a cam driving motor between a main shaft and a tool magazine, and a cam mechanism provided on the cam shaft to advance and retreat. And forward and reverse rotational movement at a predetermined angle,
A tool exchanging device for arranging a tool exchanging arm for exchanging a tool between a spindle and a tool magazine, the spindle including a tool clamping device and an unclamping device composed of a tightening and loosening cylinder of the tool clamping device. In the above, a manually switchable switching valve for supplying / discharging pressure fluid to / from the tightening / loosening cylinder, a lever for automatically switching this switching valve, and a replacement arm shaft of the exchange arm shaft on the cam shaft of the cam mechanism. A pair of cam members projecting with an angular phase difference in order to operate the lever in synchronization with forward / backward movement and forward / reverse rotational movement of a predetermined angle to control the supply / discharge of the pressure fluid to / from the tightening / loosening cylinder. A tool changer characterized by having.