JP2007044792A - Machine tool for long object machining - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive machine tool for long object machining, suitable for miniaturization by providing workpiece holders into which a workpiece can be inserted on a pair of bearing bases moving in a contacting/separating direction, and by fitting and holding both end parts of the workpiece by the workpiece holders to be rotated. <P>SOLUTION: This machine tool is provided with a Z-axis rail 3 extending in a left and right direction on a frame 1, the pair of bearing bases 15 to be mutually movable in the contacting/separating direction on the Z-axis rail 3, the workpiece holder 18 capable of being inserted by the long workpiece W to be coaxial and rotatable on each of the bearing bases 15, a Z-axis moving device 5 for mutually moving the bearing bases 15 in the contacting/separating direction, a driving device 14 for rotating the workpiece holder 18 and a tool rest 7 for machining the workpiece W. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a machine tool for processing long objects that processes ends of pipes, shafts and the like.

There existed patent document 1 as a prior art. In other words, a pair of left and right headstocks are provided on the bed so as to be movable in the contact / separation direction (Z-axis direction), and workpiece chucks, end face tools, and center drills are provided at opposite ends of the main shafts supported by each headstock. A turret that moves in the same direction as the headstock is provided on the bed, a turret is provided on the turret, and a moving chuck is provided between the headstocks so as to be movable in the left and right and up and down directions.

Then, after clamping the black skin workpiece with a moving chuck to be positioned coaxially with each main shaft, each main shaft is rotated, and the end hole of the workpiece and the center hole of the shaft center portion are machined with the end face tool and the center drill. . Next, the workpiece is clamped by a workpiece chuck provided on the spindle, the workpiece is clamped by the moving chuck, and the outer periphery of the workpiece is machined by a tool attached to the tool post while the workpiece is rotated by the spindle. .

In Patent Document 1, since the workpiece is not supported by penetrating the workpiece chuck of the spindle stock, when machining the end portion of the workpiece, a dedicated moving chuck provided at the intermediate portion of each spindle stock is used. It was necessary to support the middle part of the workpiece. Further, the spindle of the headstock is firmly supported by bearings at both ends in the axial direction. For this reason, it becomes expensive and large.
Japanese Patent Laid-Open No. 3-117501

The present invention provides a work holder through which a work can be inserted into a pair of bearing bases that move in the contact / separation direction, fits and holds both ends of the work with the work holder, and rotates the work to reduce the cost and size. The purpose is to obtain a new machine tool for long workpieces suitable for machining.

The present invention is configured as follows to achieve the above object. That is, according to the first aspect of the present invention, a Z-axis rail extending in the left-right direction is provided on the frame, and a pair of bearing bases are provided on the Z-axis rail so as to be movable toward and away from each other. A work holder that can be inserted is provided coaxially and rotatably, and a chuck for holding the work is provided on the work holder, the Z-axis moving device that moves the bearing bases in the contact and separation directions, and the work holder is rotated. A driving device and a tool post for processing the workpiece are provided.
According to a second aspect of the present invention, as the Z-axis moving device, a pair of Z-axis movable bases are provided on the Z-axis rail so as to be movable toward and away from each other, and each Z-axis movable base is disposed outside each bearing base. The Z-axis movable base is provided with a tool rest, and an engagement / disengagement device for engaging / disengaging the tool rest and the bearing base adjacent to each other on the right and left sides is provided, and a clamp device for fixing / releasing each bearing base to / from the frame. And a Z-axis motor for moving the Z-axis movable table in the left-right direction and an X-axis motor for moving the tool rest in a direction orthogonal to the Z-axis movable table.
According to a third aspect of the present invention, a drive shaft parallel to the Z-axis rail is provided as the drive device, and a rotary body is provided on the drive shaft so as not to be relatively rotatable and slidable to the left and right. A toothed pulley or sprocket is provided, a toothed belt or chain is suspended between the toothed pulley or sprocket, and a main shaft motor is connected to the drive shaft.

In the present invention, each work holder can be set to a distance suitable for the length of a work such as a pipe or a shaft by moving the pair of bearing stands in the contact / separation direction with the Z-axis moving device. As a result, each work holder can support both ends of the work, and even if the work holder has a simple bearing structure with respect to the bearing stand, the work is supported with high precision and firmness, and both ends of the work are highly accurate. Can be processed.
Further, since the interval between the work holders is determined by moving the tool post for machining the workpiece, the structure is simplified and the interval between the work holders can be performed with high accuracy.
The work holder is rotated by rotating a drive shaft parallel to the Z-axis rail, and the drive shaft is rotated by a toothed pulley or sprocket and a toothed belt or chain suspended between them. As a result, the axial length of the work holder that supports the work can be shortened, and end machining of a short work can be easily performed.

Embodiments of the present invention will be described below with reference to the drawings. In the drawings, FIG. 1 is a cross-sectional front view of an essential part showing an embodiment of the present invention, FIG. 2 is a left side view for explaining FIG. 1, FIG. 3 is a cross-sectional view of the main part of a bearing base, and FIG. FIG.

1 and 2, reference numeral 1 denotes a frame (bed), and a support base 2 having a triangular shape in side view is fixed to the front side of the frame 1. A Z-axis rail 3 extending in the left-right direction in FIG. 1 is provided on the front side of the support base 2, and a pair of left and right Z-axis movable bases 4 are attached to the Z-axis rail 3 so as to be slidable left and right. Each Z-axis movable table 4 is individually moved in the left-right direction along the Z-axis rail 3 by a Z-axis motor (Z-axis moving device) 5 composed of servo motors provided on the left and right sides of the support table 2.

A tool rest 7 is attached to each Z-axis movable base 4 so as to be slidable in the vertical direction in FIG. 1, and these tool rests 7 are individually provided by X-axis motors (servo motors) 8 attached to the top of each Z-axis movable base 4. Moved up and down. A turret 9 is attached to each of the tool rests 7 so as to face left and right, and the turret 9 is turned around a left and right axis by a turning motor (servo motor) 10. Various cutters 11 such as a cutting tool and a center drill are attached to the outer periphery of each turret 9.

A drive shaft 13 composed of a ball spline is arranged in parallel with the Z-axis rail 3 on the support base 2 described above, and both left and right ends thereof are rotatably attached to the support base 2 through bearings. The drive shaft 13 is connected to a spindle motor (drive device) 14 attached to the support base 2 via a toothed pulley 23.

A pair of left and right bearing bases 15 are arranged at the left and right intermediate portions of each Z-axis movable base 4, and are attached to the Z-axis rail 3 through a mounting base 15a (FIG. 2) so as to be slidable left and right. A rotating body 16 is rotatably attached to the upper end portion, and a work holder 18 is rotatably attached to the lower end portion of the bearing base 15. As shown in FIG. 3, the rotating body 16 and the work holder 18 are connected to each other via toothed pulleys 23 and 24 and a toothed belt 25.

As shown in FIG. 3, the rotating body 16 has a holding ring 16b fitted and fixed to a slider 16a that is slidably fitted to the drive shaft 13 and is non-rotatable. The holding ring 16b is fixed to the upper bearing. 17 is rotatably supported on the upper end portion of the bearing stand 15. A toothed pulley 23 is fixed to one side of the holding ring 16b.

The work holder 18 is configured as shown in FIGS. That is, a fitting cylinder 19 into which a long workpiece W such as a pipe or a shaft is fitted is slidably fitted into the support ring 20 and is slidably fitted through the support ring 20 by the lower bearing 26. It is rotatably supported at the lower end of the. The fitting cylinder 19 is formed of a collet chuck and has a clamping claw 19a that is cut to the left in FIG. 4 and is always moved and urged to the right (clamping direction) by an operating spring 21. The clamping claw 19a is elastically deformed in the axial direction by a tapered surface 20a formed on the inner periphery.

The clamping of the workpiece W by the clamping claws 19a is released by the chuck releasing device 22 when the workpiece W is removed. That is, as shown in FIG. 4, the release arm 22a is pivotally supported at the lower end of the bearing base 15 and its one end is brought into contact with the right end surface of the fitting cylinder 19 in FIG. The portion is connected to the piston rod 22c of the release cylinder 22b attached to the bearing base 15. Then, by pressing the other end portion of the release arm 22a outward by the piston rod 22c, the fitting cylinder 19 is moved to the left in FIG. 4, and the clamping claw 19a is elastically restored outward in the radial direction. To release the workpiece W.

A toothed pulley 24 is fixed to one side of the support ring 20, and a toothed belt 25 is suspended between the toothed pulley 24 and the above-described toothed pulley 23 on the drive shaft 13 side, so that the drive shaft 13 rotates. It is transmitted to the fitting cylinder 19. The toothed pulleys 23 and 24 may be replaced with sprockets, and the toothed belt 25 may be replaced with a chain.

Of the above-described tool rest 7 and bearing base 15, an engagement / disengagement device 27 for engaging / disengaging the tool rest 7 and the bearing base 15 adjacent to each other on the left and right is provided, and each bearing base 15 is fixed / released to / from the frame. A clamping device 30 is provided.

As shown in FIG. 1, the engagement / disengagement device 27 fixes an engagement ring 27 a to the side of the turret 7 facing the bearing pedestal 15 so as to protrude sideways, and the turret of the bearing pedestal 15. An engaging pin 27b to which the engaging ring 27a is fitted and locked is protruded and fixed to a side portion facing the member 7. As a result, the tool post 7 is moved in the direction of the bearing stand 15 to position the engagement ring 27a below the engagement pin 27b, and then the tool post 7 is moved upward to engage the engagement ring 27a. The tool post 7 is connected to the bearing stand 15 by engaging with the pin 27b. Further, by moving the tool rest 7 downward from the above state, the engagement ring 27a is detached from the engagement pin 27b, and the connection between the tool rest 7 and the bearing base 15 is released.

The clamping device 30 is configured as shown in FIG. That is, the clamp cylinder 30a is attached to the upper part of the mounting base 15a of each bearing base 15, the lower clamp claw 30b is opened and closed by the clamp cylinder 30a, and the fixed base 3a of the Z-axis rail 3 is clamped by the clamp claw 30b. To release. As a result, when each bearing base 15 is moved in the Z-axis direction and the distance between both is set to a predetermined value, the clamp cylinder 30a is operated in the locking direction so that each bearing base 15 is fixed to the fixed base 3a, and hence the frame. Fix to 1.

Here, the Z-axis movable table 4, the tool rest 7, the Z-axis motor 5, and the engagement / disengagement device 27 described above constitute the Z-axis movement device of the present invention. Further, the drive shaft 13, the spindle motor 14, the rotating body 16, the toothed pulleys 23 and 24, and the toothed belt 25 described above constitute the drive device of the present invention. The rotating body 16, the toothed pulleys 23 and 24, and the toothed belt 25 include the rotating body 16, the toothed pulleys 23 and 24, and the teeth provided on one of the left and right bearing bases 15. Only the belt 25 may be used. The toothed belt 25 may be a flat belt or a V belt, and the toothed pulleys 23 and 24 may be a flat pulley or a V pulley.

Next, the operation mode of the embodiment will be described. First, the engagement / disengagement device 27 is engaged to operate the tool rest 7 and the bearing base 15 to engage with each other. That is, the Z-axis motor 5 is activated in the forward direction to move the tool post 7 in the direction of the bearing base 15 (advance), the engagement ring 27a is positioned below the engagement pin 27b, and then the X-axis motor 8 is moved. The tool post 7 is moved upward to move upward, the engagement ring 27 a is engaged with the engagement pin 27 b, and the tool post 7 is connected to the bearing base 15.

Next, the Z-axis motor 5 is activated in the march direction to move the Z-axis movable table backward, and the interval between the bearing tables 15 is set to an interval suitable for the length of the workpiece W. Next, the clamp device 30 is locked to fix the bearing base 15 to the frame 1, and the work W is fitted to the work holder 18. Next, the X-axis motor 8 is actuated in the downward direction to move the tool post 7 downward, the engagement ring 27a is detached from the engagement pin 27b, and the connection between the tool post 7 and the bearing base 15 is released.

Next, the spindle motor 14 is activated to rotate the workpiece W via the drive shaft 13, the rotating body 16, the toothed pulleys 23 and 24, the toothed belt 25, and the work holder 18. In parallel with this, the Z-axis motor 5, the X-axis motor 8, and the turning motor 10 are started according to a preset program. Then, the tool 11 attached to the tool rest 7 is selected, and the tool 11 is moved in the X-axis and Z-axis directions via the Z-axis movable base 4 and the tool rest 7, and the end of the workpiece W is selected. Will be processed.

It is a front view which shows embodiment of this invention. It is a left view for description of FIG. It is principal part sectional drawing of a bearing stand part. It is sectional drawing of a work holder part.

Explanation of symbols

1 Frame 2 Support base 3 Z-axis rail 3a Fixed base 4 Z-axis movable base 5 Z-axis motor (Z-axis moving device)
7 Tool post 8 X-axis motor 9 Turret 10 Rotating motor 11 Tool 13 Drive shaft 14 Spindle motor (drive device)
15 Bearing base 15a Mounting base 16 Rotating body 16a Slider 16b Retaining ring 17 Upper bearing 18 Work holder 19 Fitting cylinder 19a Holding claw 20 Support ring 21 Actuating spring 22 Chuck release device 22a Release arm 22b Release cylinder 22c Piston rods 23, 24 Teeth Pulley with sprocket
25 Toothed belt (chain)
26 Lower bearing 27 Engaging / disengaging device 27a Engaging ring 27b Engaging pin 30 Clamping device 30a Clamp cylinder 30b Claw

Claims (3)

A Z-axis rail (3) extending in the left-right direction is provided on the frame (1), and a pair of bearing bases (15) are provided on the Z-axis rail (3) so as to be movable toward and away from each other. A workpiece holder (18) through which a long workpiece (W) can be inserted coaxially and rotatably, and the Z-axis moving device (5) for moving the bearing base (15) in the contact / separation direction with each other, and the workpiece A long tool machining machine tool comprising a drive device (14) for rotating a holder (18) and a tool post (7) for machining the workpiece (W). The Z-axis moving device is provided with a pair of Z-axis movable bases (4) on the Z-axis rail (3) so as to be movable toward and away from each other, and each Z-axis movable base (4) is mounted on each bearing base (15). An engagement / disengagement device (27) disposed outside and provided with a tool post (7) on the Z-axis movable stand (4), and engaging and releasing the tool post (7) and the bearing stand (15) adjacent to each other on the left and right. ), A clamp device (30) for fixing / releasing each bearing base (15) to / from the frame (1), a Z-axis motor (5) for moving the Z-axis movable base (4) in the left-right direction; The long tool machining machine tool according to claim 1, further comprising an X-axis motor (8) for moving the tool post (7) in a direction orthogonal to the Z-axis movable table (4). The drive device (14) is provided with a drive shaft (13) parallel to the Z-axis rail (3), and a rotary body (16) is provided on the drive shaft (13) so as not to be relatively rotatable and slidable to the left and right. The body (16) and the work holder (18) are each provided with a toothed pulley or sprocket (23, 24), and a toothed belt or chain (25) is suspended between the toothed pulley or sprocket (23, 24). 3. A machine tool for machining long objects according to claim 1, wherein a spindle motor (14) is connected to the drive shaft (13).

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