JP2003080402A - Machine tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: Not to make a thrust load at the time of clamping a tool spindle act on a bearing to support the tool spindle in a spindle for a tool commonly used for a machining tool and a rotating tool. SOLUTION: This machine tool 1 equipped with the tool spindle 32 supported rotatably through a bearing supporting means 37 has, between the spindle 32 and a tool rest main body 31, a spindle side coupling member 42, a tool rest main body side coupling member 45 and a clamp member 43 free to be engaged with the spindle side coupling member and the tool rest main body side coupling member. This tool 1 has also a balance pressurizing member 50 free to make contact with and to be engaged with the spindle side coupling member, on the opposite side of the spindle side coupling member 42 in the axis of a tool shaft center CT3 to the side on which the clamp member 43 is provided. By the aid the balance pressurizing member 50, the thrust load working on the tool spindle 32 at the time of clamping the tool spindle 32 by the clamp member 43 can be cancelled and clamping of the tool spindle 32 can be made without applying any load on the bearing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a machine tool having a spindle for both turning and rotating tools.

[0002]

2. Description of the Related Art Conventionally, in a machine tool such as a CNC lathe, various turning tools or various rotary tools are detachably attached to the tool spindle by ATC (automatic tool change), etc. There are some spindles for this tool that are commonly used for turning and rotating tools.

[0003]

By the way, in the machine tool as described above, since the tool spindle for both the turning tool and the rotary tool is rotatably supported on the tool rest main body side,
At the time of turning by a turning tool, it is a problem to secure rigidity in the tool spindle supporting the turning tool. Further, it is desired to support the turning tool with high accuracy by the tool spindle.

Therefore, the applicant of the present invention has filed Japanese Patent Application Laid-Open No. 10-32890.
5, a spindle side coupling member provided on the tool spindle, a tool rest body side coupling member provided on the tool rest body, and these spindle side coupling members between the tool spindle and the tool rest body. And a spindle structure in which a three-piece coupling clamp mechanism including a clamp member capable of simultaneously engaging with the tool rest main body side coupling member is provided.

However, in such a three-piece coupling clamp mechanism, when the clamp member is coupled, the engaging force of the clamp member with respect to the main shaft side coupling member becomes a thrust force and is transmitted to the bearing that rotatably supports the main shaft. Inconvenience that adversely affects bearing life etc. occurs.

Further, in the conventional three-piece coupling, since the cutting force accompanying the processing acts as a thrust load on the bearing during the processing, elastic deformation of the bearing occurs,
Since the coupling may mesh with each other, there were cases where the cutting ability was reduced. However, this has a disadvantage that the cutting efficiency is lowered.

In view of the above circumstances, it is an object of the present invention to provide a machine tool that does not apply a thrust load when clamping a tool spindle to a bearing that supports the tool spindle.

[0008]

The invention according to claim 1 has a tool rest main body (31), and the tool spindle (3) is provided in the tool rest main body.
2) is rotatably supported by a bearing supporting means (37), and a turning tool (60A) or a rotary tool (60B) is selectively attachable to and detachable from the tip side of the tool spindle. In the machine tool (1), the main spindle side coupling member (42) provided on the main spindle for the tool and the turret are provided between the main spindle (32) for the tool and the main body (31) of the turret. Tool rest main body side coupling member (45) provided on the main body, a main spindle clamp position (SC1) at which these main spindle side coupling member and the tool post main body side coupling member are simultaneously engaged, and these main spindle side couplings Spindle unclamp position (SC
2) is provided with a clamp member (43) which is movable between the main shaft side coupling member (42) and the tool shaft center (CT) on the side where the clamp member (43) is provided.
On the opposite side of 3), a balance pressing member (50) is provided so as to be in contact with and engageable with the main shaft side coupling member.

According to a second aspect of the present invention, when the clamp member is unclamped, the synchronous drive means (31b, 51, 51) for synchronously driving the clamp member and the balance pressing member.
52) is provided.

According to a third aspect of the present invention, in the second aspect of the invention, the synchronous drive means is provided on the outer peripheral portion of the balance pressing member so as to be movable and returnable.
1), which has a driving force transmission means (52) between the return ring (51) and the clamp member (43) for transmitting the movement of the return ring in the tool axial direction to the clamp member. A drive means (3) provided so as to drive the return ring and the balance pressing member in opposite directions between the return ring and the balance pressing member.
1b) is provided.

According to a fourth aspect of the present invention, the engaging portions (42b, 45b) of the main shaft side coupling member and the tool post main body side coupling member are provided at the end portions of the tool main spindle on which the tool is mounted ( 32a) is formed so as to face back (that is, a shape facing the direction of arrow G in FIG. 4).

[0012]

As described above, according to the first aspect of the present invention, when the rotary tool is mounted on the tool spindle and the rotary machining is performed, the clamp member is moved to the spindle unclamp position. When the tool spindle is rotated, and when a turning tool is mounted on the tool spindle to perform turning, the clamp member is moved to the spindle clamp position to move the tool spindle with respect to the tool rest body. Make sure to clamp it. Further, the balance pressing member can cancel the thrust load acting on the tool spindle when the spindle is clamped by the clamp member, so that the tool spindle can be clamped without burdening the bearing, and the bearing is elastically deformed. The movement of the spindle can be prevented, and highly accurate machining is possible.

According to the second aspect of the present invention, since the synchronous drive means enables the synchronous disengagement of the clamp member and the balance pressing member, either one of them is first to be unclamped when the tool spindle is unclamped. Inadvertent thrust load action on the bearing due to separation from the main shaft side coupling member is prevented, and a highly reliable machine tool can be provided.

In the third aspect of the present invention, since the clamp member and the balance pressing member can be driven only by driving the return ring, the synchronous driving means can be realized with a simple structure.

In a fourth aspect of the present invention, the engaging portions (42b, 45b) are formed so as to face the end (32a) of the tool spindle on which the tool is mounted. Therefore, even if chips etc. enter, it will be difficult to reach the engaging part, and when clamping the tool spindle, the chips will be caught in the engaging part and prevent the situation of clamp failure. You can do it.

The numbers in parentheses are for convenience of showing the corresponding elements in the drawings, and the present description is not limited to the description in the drawings.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing an example of a machine tool according to the present invention, FIG. 2 is a perspective view showing the inside of a front door of the machine tool shown in FIG. 1, and FIG. 3 is a tool rest of FIG. FIG. 4 is a side sectional view showing details of the periphery of the tool spindle, and FIG. 4 is a side sectional view showing details of the clamp portion of FIG.

As shown in FIG. 1, a machine tool 1 such as a CNC lathe has a rectangular parallelepiped frame 2 extending in the directions of arrows H and I in FIG. 1, which is the horizontal Z-axis direction. A front door 3 is provided on the front side of the sheet 2 (that is, on the front side of the plane of FIG. 1) so as to be openable / closable in the directions of the arrows H and I. Inside the frame 2, as shown in FIG.
A headstock 6 is installed, and a work spindle 7 is attached to the headstock 6.
Is axially rotatably supported in the directions of arrows Q and R in the figure with the axes CT1 arranged in parallel in the directions of arrows H and I, which are the Z-axis directions. There is. On the arrow I side of the work spindle 7, a chuck 9 is provided so that the work 10 to be processed can be gripped by a plurality of chuck claws 9b. That is, the chuck 9 (and the work 10 gripped by the chuck 9) provided on the work spindle 7 is rotatable about the axes Q and R.

Further, as shown in FIG. 2, inside the frame 2, a first linear motion guide device 20 extending in the directions of arrows H and I is laid at a position on the arrow I side of the work spindle 7. A tailstock 21 is provided on the first linear motion guide device 20 so as to be slidably movable in the directions of arrows H and I, that is, in the Z-axis direction. The tailstock 21 is provided with a tailstock shaft 22 capable of supporting the arrow I side of the work 10 gripped by the chuck 9 according to the size and shape of the work 10 to be processed or the mode of processing.

Further, in the frame 2, a well-known tool magazine 5 is installed on the back side of the work main shaft 7 and the like in FIG. 1 and the like, and the tool magazine 5 has a plurality of types of turning tool units 60A and rotary tools. Tool units such as the tool unit 60B are held and stored. In the vicinity of the tool magazine 5, a known automatic tool changing device 17 (ATC device) can take out the tool unit held and stored in the tool magazine 5 and attach it to a tool spindle 32 described later. The tool unit mounted on the tool spindle 32 can be detached and held in the tool magazine 5.

Further, inside the frame 2, as shown in FIG. 2, at a position on the arrow I side of the work spindle 7, at a position diagonally upward and rearward of the first linear motion guide device 20 in FIG. A second linear motion guide device 11 extending in the directions of arrows H and I is laid at a position closer to the front side of the paper than the tool magazine 5 and the automatic tool changing device 17 in FIG.
1, a tool rest base 12 is provided so as to be slidably movable in the directions of arrows H and I, that is, in the Z-axis direction. On the other hand, the turret base 12 has a third shape extending in the directions of arrows D and E in FIGS. 1 and 2, which is the direction of the X axis which is perpendicular to the Z axis direction and slightly inclined from the vertical direction. The linear motion guide device 15 is laid (therefore, the third linear motion guide device 15 is inclined toward the back side of the paper in FIGS. 1 and 2), and the third linear motion guide device 15 includes the tool rest 13 Are provided so as to be slidably movable in the directions of arrows D and E, that is, in the X-axis direction.

As shown in FIG.
As shown in FIG. 3, a spindle mounting portion 30 is formed, and the spindle mounting portion 30 has a Y perpendicular to the X-axis direction (arrows D and E directions) and the Z-axis direction (arrows H and I directions). The main body of the tool rest 13 is a headstock 31 that is rotatably supported in the directions of arrows T and U (B axis direction) around an axis CT2 that is parallel to the axial directions A and C of the drawing. Is provided so as to form a part of. An appropriate rotary drive motor (not shown) is built in the tool rest 13, and an appropriate power transmission means composed of gears, shafts or the like is provided between the rotary drive motor and the head stock 31. (Not shown)
However, by transmitting the power from the rotation driving motor, the head stock 31 is driven to rotate about the shaft center CT2 in the directions of arrows T and U (B-axis direction) at a predetermined indexing angle. It is provided freely.

Further, the spindle mounting portion 30 and the headstock 3
An appropriate fixing means (not shown) for fixing / releasing the fixing of the headstock 31 side with respect to the main shaft mounting portion 30 side is provided between the two. In other words, headstock 3
1 can be rotationally driven and positioned at a predetermined indexing angle in the directions of arrows T and U in the figure by a power transmission means, a fixing means, and the like.

As shown in FIG. 3, the head stock 31 has a substantially cylindrical shape opened at least in the direction of the arrow F, and inside the head stock 31, a tool spindle supported via a bearing unit 37. 32 is provided (the head stock 31 is one casing body formed by combining a plurality of parts, as shown in FIG. 3). The tool spindle 32 has a shape extending in the arrow F and G directions (axial direction of the tool spindle 32) in the headstock 31, and has the above-described bearing unit 37.
By being supported via the axis C in the directions of arrows F and G
The shaft is rotatable about T3 in the directions of arrows J and K in the figure. The bearing unit 37 has a thrust bearing device 37a arranged on the arrow F side which is the tip side of the tool spindle 32 and a roller bearing device 37b arranged on the arrow G side which is the rear end side of the tool spindle 32. There is.

As described above, since the head stock 31 can be rotationally driven / positioned with respect to the spindle mounting portion 30 in the directions of arrows T and U at a predetermined indexing angle, the head stock 31 is provided on the head stock 31. Similarly, the tool spindle 32 is also rotatable in the directions of arrows T and U at a predetermined indexing angle. Therefore, the tool spindle 32 is positioned such that the tip of the tool spindle 32 is directed in the direction of arrow H in the figure, or is positioned in the direction of arrow D in the figure, or the B
It can be positioned in any of various directions along the axis.

The tip side of the tool spindle 32 (that is, the arrow F in the figure)
As shown in FIGS. 3 to 4, the side) is a tool mounting portion 33 which is basically formed in a substantially conical shape. The tool mounting portion 33 has a turning tool unit or a rotary tool unit. Is detachable (note that FIGS. 3 and 4 show a state in which neither the turning tool unit 60A nor the rotary tool unit 60B is attached to the tool spindle 32).

Further, the spindle drive motor 70 is the tool spindle 3
It is a so-called built-in type that is directly connected to 2.
By driving the spindle driving motor 70, the tool spindle 32 can be driven to rotate about the axis CT3 in the directions of arrows J and K in the figure. That is, the rotary tool unit 60B is attached to the tip of the tool spindle 32, and the tool spindle 32 is driven to rotate in the directions of the arrows J and K so that rotary machining such as milling can be performed.

In addition, the headstock 31 and the tool spindle 32
Between them, a coupling clamp mechanism 40 is provided in the vicinity of the thrust bearing device 37a described above and at a position on the arrow F side of this. That is, the coupling clamp mechanism 40 has a spindle coupling 42 fixedly provided on the tool spindle 32, as shown in FIG. The spindle coupling 42 has a base portion 42a formed on the outer peripheral side of the tool spindle 32 in the shape of a flange, that is, in the shape of an annular plate substantially perpendicular to the directions of arrows F and G. G direction, ie, spindle end 3
A plurality of protrusions 42b are provided on the surface facing away from 2a in the direction of the arrow G. Each protrusion 4
2b is formed in a linear shape extending radially from the axial center CT3.

Further, the coupling clamp mechanism 40 is
Fixing coupling 4 provided on the headstock 31
Have five. The fixing coupling 45 is arranged corresponding to the outer peripheral side of the spindle coupling 42 described above, and has a base portion 45a fixed to the head stock 31, and the base portion 45a extends in the directions of arrows F and G. It is formed in a substantially vertical annular plate shape that surrounds the outside of the spindle coupling 42. On the surface of the base portion 45a facing the arrow G direction, a plurality of protrusions 45b are provided so as to project in the arrow G direction. Each of the protrusions 45b is formed in a streak shape radially extending around the axial center CT3.

Further, in the head stock 31, the head stock 31 is located on the arrow G side of the above-mentioned fixing coupling 45, that is, on the side opposite to the spindle end face 32a.
Inside, a hollow cylinder 41 is formed. The cylinder 41 is arranged on the outer side in the radial direction of the tool spindle 32 and has a ring shape concentric with the tool spindle 32. The coupling clamp mechanism 40 has a clamp coupling 43 supported by the headstock 31 via the cylinder 41. That is, the clamp coupling 43 is basically a piston body which can be moved and driven in the directions of arrows F and G by hydraulic oil or the like in the cylinder 41. Clamp coupling 4
On the arrow F side of 3, there is formed a flat plate-shaped facing portion 43a facing the arrow F direction. Cylinder 4 as described above
Since 1 has a ring shape concentric with the tool spindle 32, the facing portion 43a also has a ring shape concentric with the tool spindle 32, and the facing portion 43a further has a spindle shape in the direction of the arrow F. Coupling 42 and fixing coupling 45
Are formed to face each other. A plurality of protrusions 43b are provided on the surface of the facing portion 43a facing the arrow F direction so as to project in the arrow F direction. Each protrusion 4
3b is formed in a striated shape extending radially around the axial center CT3.

The left side of the spindle coupling 42 in FIG.
That is, on the opposite side in the axial CT3 direction of the side on which the clamp coupling 43 is provided, an annular balance ring 50 is provided on the cylinder 31a formed in the head stock 31 in a predetermined direction in the arrow F and G directions. The balance ring 50 is provided so as to be slidable over the stroke thereof, and a pressing surface 50a is formed on the right side of the balance ring 50 in the figure so as to be capable of abuttingly engaging with a side surface 42c of the spindle coupling 42.

A return ring 51 is provided on the outer peripheral portion of the balance ring 50 in FIG. 4 so as to be slidable in a cylinder 31b formed in the head stock 31 in the directions of arrows F and G for a predetermined stroke, and the return Ring 51
Is formed so as to be capable of abuttingly engaging with a pin 52 loosely fitted in a hole 45c formed through the fixing coupling 45 in the directions of arrows F and G.

That is, when the tool spindle 32 is clamped, the clamp coupling 43 is moved and driven in the direction of arrow F by the pressure oil supplied to the cylinder 41 via the oil passage 55, and as shown in the lower half of FIG. When arranged at the main spindle clamp position SC1, the plurality of protrusions 43b provided on the facing portion 43a mesh with the plurality of protrusions 42b of the main spindle coupling 42 and the plurality of protrusions 45b of the fixing coupling 45. The main shaft coupling 42 is clamped with respect to the fixing coupling 45 in a known three-piece coupling manner. That is, the tool spindle 32 provided with the spindle coupling 42 is clamped and fixed to the head stock 31 side so as to restrain the rotation in the arrow J and K directions.

At this time, the balance ring 50 is also connected to the oil passage 53.
By the pressure oil supplied to the cylinder 31a via the pressing force in the direction of the arrow G, the pressing surface 50a and the side surface 42c of the spindle coupling 42 abut with a predetermined pressing force. Since the clamp coupling 43 applies a predetermined clamping force in the F direction in the drawing on the protrusion 42b side of the spindle coupling 42, as described above, the spindle coupling 42
The clamping force in the direction of arrow F from the clamp coupling 41 and the pressing force in the direction of arrow G from the balance ring 50 act, and as a result, the clamping force in the direction of arrow F from the clamp coupling 43 is applied. It is canceled by the pressing force of.

Normally, the clamping force in the direction of arrow F acting on the tool spindle 32 from the clamp coupling 43 via the spindle coupling 42 acts as a thrust load on the thrust bearing 37a supporting the tool spindle 32. This thrust load is canceled by the pressing force applied to the spindle coupling 42 by the balance ring 50, and the tool spindle 32 is caused by the engagement of the clamp coupling 43 with the spindle coupling 42 and the fixing coupling 45. Thrust load no longer acts.

When unclamping the tool spindle 32,
The oil passages 53 and 55 are drained, and the pressure oil is supplied to the cylinder 31b on the left side of the return ring 51 in the figure.
Then, the return ring 51 is driven to move in the direction of arrow G, and the balance ring 50 is driven to be pressed in the opposite direction of arrow F. As a result, the return ring 51 abuts on the pin 52 loosely fitted in the hole 45c of the fixing coupling 45, presses the pin 52 in the direction of arrow G to move it in the direction of arrow G, and further the pin 52 moves in the direction of arrow G. When moved in the G direction, the clamp coupling 43 is fixed by the pin 52.
Is driven in the direction of arrow G. Then, the clamp coupling 43 is arranged at a predetermined spindle unclamp position SC2 as shown in the upper half of FIG.

Then, the protrusion 43b of the clamp coupling 43 is disengaged from the protrusion 42b of the spindle coupling 42 and the protrusion 45b of the fixing coupling 45, and the spindle coupling is fixed to the fixing coupling 45. 42 is unclamped. That is, the tool spindle 32
Is released from the constraint on the rotation in the directions of the arrows J and K, and becomes rotatable in the directions of the arrows J and K.

Further, the cylinder 31 of the return ring 51
By supplying the pressure oil to b, the balance ring 50 is pressed and driven in the direction of arrow F in synchronization with the opening operation of the clamp coupling 41, and the balance ring 50 and the spindle coupling 42, which have been in contact with each other until then, The contact relationship of is released in synchronization with the opening operation of the clamp coupling 41. Then, the pressing force acting from the balance ring 50 to the spindle coupling 42 until then disappears, and the spindle coupling 42 becomes the clamp coupling 43.
And disengaged from both the spindle coupling 42,
The axial center CT that was acting on the spindle coupling 42 until then
The pressing force and clamping force in 3 directions will not work together,
The tool spindle 32 is in a smoothly rotatable state without any thrust load from the spindle coupling 42 and the balance ring 50 acting on the thrust bearing 37a.

As described above, by sharing the driving cylinder 31b of the return ring 51 with the driving cylinder of the balance ring 50, the clamp coupling 43 and the balance ring 50 are synchronously opened only by driving the return ring 51. The operation can be enabled. As a result, when the tool spindle 32 is switched from the fixed state to the rotatable state, an unbalanced thrust force acts on the spindle coupling 42 in the direction of the axial center CT3 to deform and damage the spindle coupling 42, and the bearing. It is possible to prevent an excessive thrust load from acting on 37, resulting in a highly reliable spindle structure.

Note that the synchronous release mechanism of the return ring 51 and the clamp coupling 43 uses a common cylinder such as the above-mentioned drive cylinder 31b, and also allows the cylinders to communicate with each other to supply the hydraulic pressure for opening at the same time. In this case, any configuration may be used, such as driving or using an appropriate mechanical interlocking mechanism.

Since the machine tool 1 and the like are constructed as described above, in order to process the work 10 with the machine tool 1, first, the work 10 is gripped by the chuck 9 (or the work gripped by the chuck 9). The tailstock shaft 22 on the arrow I side of 10
Support). Next, the tool spindle 32 equipped with the turning tool unit 60A or the rotary tool unit 60B is attached to the headstock 31 with respect to the spindle mounting portion 30.
By arranging in a desired direction by rotating and positioning in the directions T and U, the turret base 12 is driven to move in the directions H and I and the turret 13 is driven to move in the directions D and E. The machining is advanced while changing the relative position between the tip of the turning tool unit 60A or the rotary tool unit 60B mounted on the tool spindle 32 and the workpiece 10 in the X-axis direction or the Z-axis direction.

The turning tool unit 6 is attached to the tool spindle 32.
When 0A is mounted, the C-axis control state of the work spindle 7 is released to the normal rotation speed control state, the work spindle 7 is axially driven in the directions of arrows Q and R, and gripped by the chuck 9. The work 10 is rotated and driven in the directions of arrows Q and R. On the other hand, the tool spindle 32 is not rotated on the side of the tool rest 13 and the coupling clamp mechanism 40 has the structure shown in FIG.
Connect the clamp coupling 43 to the arrow F as shown in the lower half.
The balance ring 50 is moved in the arrow G direction while being driven and moved in the direction to be arranged at the spindle clamp position SC1. As a result, the clamp coupling 43, the main shaft coupling 42, and the fixing coupling 45 are engaged with each other in a state where the balance ring 50 cancels the clamping force in the direction of arrow F, and the main shaft coupling with respect to the fixing coupling 45. Clamp 42.

Then, the tool spindle 32 has its arrows J, K
It is clamped and fixed to the headstock 31 side while being restricted from rotating in any direction. Thus, the turning tool unit 60A mounted on the tool spindle 32 is fixed to the spindle mounting portion 30 and the like, and the workpiece 10 is turned (outer diameter machining, end face machining, etc.).

When turning by the turning unit 60A, as described above, the clamp coupling 4 is used.
The clamping force in the direction of arrow F from 3 is the balance ring 50.
The thrust bearing 37a rotatably supports the tool spindle 32 because it is canceled by the pressing force in the direction of arrow G due to
The thrust bearing is prevented from elastically deforming at the time of turning without an excessive thrust load acting on the shaft, and thus it becomes possible to perform high-precision processing.

Further, the rotary tool unit 6 is attached to the tool spindle 32.
When 0B is mounted, the work spindle 7 is kept in the rotation angle control state, that is, the C-axis control state. Further, on the tool post 13 side, in the coupling clamp mechanism 40,
The clamp coupling 43 is moved and driven in the direction of arrow G by the return ring 51 and the pin 52 to be arranged at the spindle unclamp position SC2.
3, the main shaft coupling 42 and the fixing coupling 45
Release the engagement of.

As a result, the spindle coupling 42 is unclamped with respect to the fixing coupling 45, the tool spindle 32 is made rotatable in the directions of the arrows J and K, and then the tool spindle 32 is fixed. Rotation of the workpiece 10 (milling, etc.) is performed by rotating the workpiece 10 by rotating the tool unit spindle 60B mounted on the tool spindle 32 in the directions of arrows A and B so as to rotate the tip of the rotating tool unit 60B. Try to do it.

When exchanging the tool unit mounted on the tool spindle 32 during machining, the desired tool unit held and stored in the tool magazine 5 is taken out by the above-mentioned automatic tool exchanging device 17. At the same time, the tool unit attached to the tool spindle 32 is removed, and the desired tool unit is attached to the tool spindle 32 in a form of replacing them.

As described above, according to this embodiment, the clamping of the tool spindle 32 to the headstock 31 during turning is performed by fixing the three couplings for the fixed side, the rotating side and the connection and canceling the thrust load as described above. Since it is realized by the coupling clamp mechanism 40 using the balance ring 50 for the tool, the tool spindle 32 can be clamped with higher rigidity than when the spindle is clamped by a mechanism such as a disc brake. That is, the rigidity can be favorably ensured in the tool spindle 32 that supports the turning tool unit 60A. Further, as in the conventional three-piece coupling clamp mechanism, when the tool spindle 32 is fixed, the thrust force from the clamp coupling 43 acts on the bearing 37 that rotatably supports the tool spindle 32. Therefore, even if the clamping force of the clamp coupling 43 is made strong, it is possible to prevent the bearing 37 from being adversely affected, and it is possible to easily cope with a turning process in which a large thrust load acts. Can be done.

Further, the protrusions 42b and 45b, which are the engaging portions of the main shaft coupling 42 and the fixing coupling 45 of the coupling mechanism 40, with respect to the end 32a of the tool main shaft 32 on which the tool is mounted. Since it is formed so as to face back, chips 32 and the like generated during processing will not end 32.
It is possible to prevent as much as possible from entering from the a side and reaching the protruding portions 42b and 45b. As a result, the engaging portions of the spindle coupling 42 and the fixing coupling 45,
Protrusion 43b that is an engaging portion of the clamp coupling 43
It is possible to prevent the occurrence of a situation in which the cutting chips are caught in the gap between and and the clamp becomes defective.

The balance pressing member such as the balance ring 50 arranged to face the clamp coupling 43, which is a clamp member, is not limited to the annular shape as in the embodiment,
It may have any shape as long as it can cancel the clamping force of the clamp coupling 43, and may be composed of, for example, a plurality of pressing members provided so as to be movable in the directions of arrows F and G.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of a machine tool according to the present invention,

2 is a perspective view showing the inside of a front door of the machine tool shown in FIG. 1,

3 is a side sectional view showing details of the periphery of the tool spindle in the tool rest of FIG. 2;

FIG. 4 is a side sectional view showing details of the clamp portion of FIG.

[Explanation of symbols]

1 ... Machine tool 31 ... Turret body (headstock) 31b. Synchronous drive means, drive means (cylinder) 32. Tool spindle (tool spindle) 37. Bearing support means (bearing unit) 42. Spindle side coupling member (spindle coupling) 42b, 45b ... Engaging portion (projection portion) 43 ... Clamp member (clamp coupling) 45 ... Turret body side coupling member (fixing coupling) 50 ... ... balance pressing member (balance ring) 51 ... synchronous drive means (return ring) 52 ... synchronous drive means, power transmission means (pin) 60A ... turning tool (turning tool unit) 60B ... rotary tool (rotary tool unit) ) SC1 …… Spindle clamp position SC2 …… Spindle unclamp position CT3 …… Tool shaft center (axis center)

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yoshinori Mori             Aichi Prefecture Oguchi-machi Oguchi-machi Large-scale small-scale character boarding number 1               Yamazaki Mazak Co., Ltd. Head Office Factory F term (reference) 3C045 AA02 BA13 BA40 FD03

Claims (4)

[Claims] 1. A tool rest main body is provided with a tool spindle supported rotatably through bearing supporting means on the tool rest main body, and a turning tool or a turning tool is provided on the tip side of the tool spindle. In a machine tool in which a rotary tool is selectively removable, between the tool spindle and the tool rest body, a spindle side coupling member provided on the tool spindle and provided on the tool rest body. Turret main body side coupling member, a main spindle clamping position at which these main spindle side coupling member and turret main body side coupling member are simultaneously engaged, and these main spindle side coupling member and turret main body side coupling member A clamp member that is movable between at least one of the main shaft unclamping position and the main shaft unclamping position, and the clamp member of the main shaft side coupling member is provided. On the opposite side of the side of the tool axis, the balance pressing member which is configured by providing freely abutting engagement with respect to the spindle side coupling member, the machine tool. 2. The machine tool according to claim 1, further comprising synchronous drive means for synchronously driving the clamp member and the balance pressing member when the clamp member is unclamped. 3. The synchronous drive means has a return ring movably driven on the outer peripheral portion of the balance pressing member, and a tool of the return ring is provided between the return ring and the clamp member. A driving force transmitting means capable of transmitting movement in the axial direction to the clamp member is provided, and between the return ring and the balance pressing member,
The machine tool according to claim 2, further comprising drive means for driving the return ring and the balance pressing member in opposite directions. 4. An engagement portion between the main shaft side coupling member and the tool post main body side coupling member is formed so as to face the end of the tool main spindle on which the tool is mounted. The machine tool according to claim 1, which is configured.