JP6517062B2 - Machine tool and control device for the machine tool - Google Patents

Description

  The present invention relates to a machine tool that processes a workpiece while sequentially cutting chips during cutting, and a control device for the machine tool.

Conventionally, the cutting tool is specified with respect to the work by relative movement between the work holding means for holding the work, the cutter rest for holding the cutting tool for cutting the work, and the work holding means and the cutter rest. The work holding means and the blade base relative to each other so that the cutting tool is fed in the machining feed direction while oscillating reciprocally along the machining feed direction. There is known a machine tool provided with vibration means for rotating and a rotating means for relatively rotating the work and the cutting tool (see, for example, Patent Document 1).
The control device of the machine tool controls driving of the rotating means, the feeding means, and the vibrating means, relative rotation between the work and the cutting tool, and the processing feed direction of the cutting tool with respect to the work. Causing the machine tool to process the workpiece by means of a feed operation accompanied by the reciprocating vibration.

Patent 5033929 gazette (paragraph 0049, refer to Figure 7)

  However, in the conventional machine tool described above, chips are divided by the cutting tool, but the scattering direction of the chips immediately after the division is not considered, and when the divided chips adversely affect the work surface of the work was there.

  Therefore, the present invention solves the problems of the prior art as described above, that is, the object of the present invention is to reliably divide chips generated from a workpiece one by one and to work a work surface with chips immediately after division. A machine tool capable of preventing adverse effects and a control device for the machine tool.

In the invention according to the first aspect, the workpiece holding means for holding the workpiece, the tool rest for holding the cutting tool for cutting the workpiece, and the work relative to the workpiece holding means and the tool rest are used for cutting the workpiece a feed means for feeding operation at least in the cutting direction and the rebated feed direction crossing the direction to the workpiece the tool, the workpiece holding means and the tool rest and a vibrating means for relatively vibrating along the processing-feed direction When, and a rotation means for relatively rotating said workpiece and cutting tool, a cutting portion in a forward movement of the round trip vibration, with overlapping and cutting portion in a backward, the cutting tool the processing-feed direction in conjunction with the vibration means to send relative to the machining feed direction while reciprocating vibration and rotation means is driven and controlled along the phase between the workpiece and the cutting tool Rotation and, by said reciprocal vibration feed operation with to the processing-feed direction of the cutting tool relative to the workpiece, a machine tool for executing the machining of the workpiece while cutting the chips in duplicate portion, of the chip A moving means is provided for moving the cutting tool relative to the work in a direction intersecting the cutting direction and the machining feed direction when dividing, and the moving means is used for cutting at the time of forward movement and return movement. By performing the movement at the start of duplication of the processed portion , the above-described problem is solved.

In the invention according to claim 2 , in addition to the configuration of the machine tool described in claim 1, the moving means is configured to move the cutting tool along the rotation direction of the rotating means. It solves the above-mentioned subject further.

In the invention according to the third aspect , the workpiece holding means for holding the workpiece, the tool rest for holding the cutting tool for cutting the workpiece, and the work relative to the workpiece holding means and the tool rest are used for cutting the workpiece a feed means for feeding operation at least in the cutting direction and the rebated feed direction crossing the direction to the workpiece the tool, the workpiece holding means and the tool rest and a vibrating means for relatively vibrating along the processing-feed direction When the workpiece and provided with a cutting tool to rotate relative to a machine tool having a rotating means causes, are overlapped and cutting portion in a forward movement of the round trip vibration, and a cutting portion in a backward Te, the cutting tool the machining feed direction the machining feed direction and a vibration means and the rotating means to send relatively coordinated by drive control in while reciprocal vibration along the workpiece Relative rotation between the cutting tool, wherein the said reciprocating vibration feed operation with to the processing-feed direction of the cutting tool relative to the workpiece, the machine tool for executing the machining of the workpiece while cutting the chips in duplicate portion A control device is provided with moving means for moving the cutting tool relative to the work in a direction intersecting the cutting direction and the machining feed direction when dividing the chips, and the moving means is The above-mentioned movement is performed at the start of overlapping of the cutting portion at the time of forward movement and at the time of backward movement, thereby solving the above-mentioned problem.

According to the machine tool of the first aspect of the present invention, at the time of dividing the chips, the cutting chips are moved relative to the workpiece in the direction intersecting the processing feed direction, whereby the divided chips can be machined on the workpiece It can be made to go in the direction away from it, and the bad influence to the work processing surface of the divided chips can be prevented.
The relative movement of the cutting tool can be made at the start of overlapping of the machined parts at the time of forward movement and at the time of backward movement like the machine tool of the invention according to the first aspect.

In particular, as in the machine tool according to the second aspect of the present invention, by moving the cutting tool along the rotation direction of the rotating means, the action of moving the cut chips away from the work processing surface is improved It can be done.

According to the control device for a machine tool of the invention according to the claims 3, the control device of the machine tool, it is possible to obtain the same effect as achieved by the invention according to claim 1.

BRIEF DESCRIPTION OF THE DRAWINGS The figure which shows the outline of the machine tool of the Example of this invention. Schematic which shows the relationship between the cutting tool of the Example of this invention, and a workpiece | work. The figure which shows the reciprocation vibration and position of the Z-axis direction of the cutting tool of the Example of this invention. The figure which shows the relationship between the principal axis nth rotation, n + 1st rotation, and n + 2th rotation of the Example of this invention. FIG. 3 is a view showing reciprocating vibration and a position in a Y-axis direction of the cutting tool as viewed from a reference numeral 5 in FIG. 2. (A) is an enlarged view of a portion indicated by reference numeral 6A in FIG. 5, (B) is an enlarged view of a portion indicated by reference numeral 6B in FIG. 5, and is a concept showing change in blade surface angle viewed from the Z-axis direction Figure. (A) is a conceptual perspective view seen from the code | symbol 7A shown to FIG. 6 (A), (B) is a figure seen from the code | symbol 7B shown to FIG. 6 (B), and shows the change of the outflow angle of chips. Conceptual perspective view. The conceptual diagram which shows the change of the outflow angle of the chip seen from the code | symbol 8 of FIG.

  In the machine tool according to the present invention and the control device for the machine tool, the vibration control means moves the cutting tool relative to the work in the direction intersecting the cutting direction so that the separated chips are the work The specific embodiment may be any as long as it does not touch the processing surface and avoids damage to the processing surface.

FIG. 1 is a schematic view of a machine tool 100 provided with a control device C according to an embodiment of the present invention.
The machine tool 100 includes a main shaft 110 as a rotation means and a cutting tool stand 130A as a tool rest.
A chuck 120 as a workpiece holding means is provided at the tip of the main shaft 110.
The workpiece W is held by the spindle 110 via the chuck 120.
The spindle 110 is supported by the spindle stock 110A so as to be rotationally driven by the power of a spindle motor (not shown).

The headstock 110A is movably mounted on the bed side of the machine tool 100 by the Z-axis direction feed mechanism 160 in the Z-axis direction which is the axial direction of the spindle 110.
The spindle 110 is moved in the Z-axis direction by the Z-axis direction feeding mechanism 160 via the spindle stock 110A.
The Z-axis direction feeding mechanism 160 constitutes a spindle moving mechanism for moving the spindle 110 in the Z-axis direction.

The Z-axis direction feed mechanism 160 includes a base 161 integral with the fixed side of the Z-axis direction feed mechanism 160 such as the bed, and a Z-axis direction guide rail 162 provided on the base 161 and extending in the Z-axis direction. There is.
A Z-axis direction feed table 163 is slidably supported by the Z-axis direction guide rail 162 via a Z-axis direction guide 164.
The mover 165 a of the linear servomotor 165 is provided on the Z-axis direction feed table 163 side, and the stator 165 b of the linear servomotor 165 is provided on the base 161 side.

The headstock 110A is mounted on the Z-axis direction feed table 163, and driven by the linear servomotor 165, the Z-axis direction feed table 163 is driven to move in the Z-axis direction.
Movement of the Z-axis direction feed table 163 moves the headstock 110A in the Z-axis direction, and movement of the main shaft 110 in the Z-axis direction is performed.

A cutting tool 130 such as a cutting tool for turning a workpiece W is mounted on the cutting tool stand 130A.
The cutting tool table 130A is disposed on the bed side of the machine tool 100 by the X-axis direction feeding mechanism 150 and a Y-axis direction feeding mechanism (not shown) in the X axis direction orthogonal to the Z axis direction, the Z axis direction and the X axis direction It is provided movably in the Y-axis direction orthogonal to
In this embodiment, the Y-axis direction feeding mechanism (not shown) moves the cutting tool 130 relative to the work W in the Y-axis direction which is a direction intersecting the X-axis direction which is the cutting direction when dividing chips. It is a moving means.
The X-axis direction feeding mechanism 150 and the Y-axis direction feeding mechanism constitute a tool post moving mechanism that moves the cutting tool table 130A with respect to the main shaft 110 in the X-axis direction and the Y-axis direction.

The X-axis direction feeding mechanism 150 includes a base 151 integrated with the fixed side of the X-axis direction feeding mechanism 150, and an X-axis direction guide rail 152 provided on the base 151 and extending in the X-axis direction.
An X-axis direction feed table 153 is slidably supported by the X-axis direction guide rail 152 via an X-axis direction guide 154.

The mover 155 a of the linear servomotor 155 is provided on the X-axis direction feed table 153 side, and the stator 155 b of the linear servomotor 155 is provided on the base 151 side.
The X-axis direction feed table 153 is moved and driven in the X-axis direction by the drive of the linear servomotor 155.
The Y-axis direction feeding mechanism has the X-axis direction feeding mechanism 150 disposed in the Y-axis direction, and has the same structure as the X-axis direction feeding mechanism 150, so a detailed description of the structure will be omitted.

In FIG. 1, the X-axis direction feed mechanism 150 is mounted on the bed side via a Y-axis direction feed mechanism (not shown), and the cutting tool table 130A is mounted on the X-axis direction feed table 153.
The cutting tool base 130A is moved in the X axis direction by the movement drive of the X axis direction feed table 153, and the Y axis direction feed mechanism operates in the same manner as the X axis direction feed mechanism 150 in the Y axis direction. To move in the Y-axis direction.

  A Y-axis direction feed mechanism (not shown) may be mounted on the bed side via the X-axis direction feed mechanism 150, and the cutting tool base 130A may be mounted on the Y-axis direction feed mechanism side. A structure for moving the cutting tool table 130A in the X-axis direction and the Y-axis direction by the X-axis direction feeding mechanism 150 is conventionally known, and thus the detailed description and the illustration will be omitted.

  The tool post moving mechanism (X-axis direction feeding mechanism 150 and Y-axis direction feeding mechanism) cooperates with the spindle moving mechanism (Z-axis direction feeding mechanism 160), and the X-axis direction feeding mechanism 150 and Y-axis direction feeding mechanism Is mounted on the cutting tool stand 130A by the movement of the cutting tool stand 130A in the X-axis direction and the Y-axis direction and the movement of the spindle stand 110A (spindle 110) by the Z-axis direction feed mechanism 160 in the Z-axis direction. The cutting tool 130 is sent relative to the workpiece W in an arbitrary processing feed direction.

  As shown in FIG. 2, the cutting tool 130 is fed relative to the work W in an arbitrary processing feed direction by means of the feeding means comprising the spindle moving mechanism and the tool post moving mechanism. W is cut into an arbitrary shape by the cutting tool 130.

In the present embodiment, although both the spindle stock 110A and the cutting tool stock 130A are configured to move, the spindle stock 110A is fixed so as not to move to the bed side of the machine tool 100, and the tool rest moving mechanism The cutting tool table 130A may be moved in the X-axis direction, the Y-axis direction, and the Z-axis direction.
In this case, the feeding means is constituted by a tool post moving mechanism for moving the cutting tool table 130A in the X-axis direction, the Y-axis direction and the Z-axis direction, with respect to the main shaft 110 which is fixedly positioned and rotationally driven. By moving the cutting tool stand 130A, the cutting tool 130 can be subjected to a processing feed operation with respect to the workpiece W.

In addition, the cutting tool stand 130A may be fixed so as not to move to the bed side of the machine tool 100, and the spindle moving mechanism may be configured to move the headstock 110A in the X axis direction, the Y axis direction, and the Z axis direction. .
In this case, the feeding means is constituted by a headstock moving mechanism for moving the headstock 110A in the X axis direction, the Y axis direction, and the Z axis direction, and the head stock relative to the cutting tool rest 130A fixedly positioned. By moving 110 A, the cutting tool 130 can be made to perform a machining feed operation on the workpiece W.
In the present embodiment, the work W is rotated relative to the cutting tool 130. However, the cutting tool 130 may be rotated relative to the work W.

The rotation of the main shaft 110, the Z-axis direction feeding mechanism 160, the X-axis direction feeding mechanism 150, and the Y-axis direction feeding mechanism are driven and controlled by a control unit C1 of the control device C.
The control unit C1 is provided with vibration control means for controlling the headstock 110A or the cutting tool stand 130A to move in the respective directions while reciprocating the respective feed mechanisms as vibrating means along corresponding moving directions. ing.

  Each feed mechanism is controlled by the control unit C1 to move the spindle 110 or the cutting tool table 130A forward (forward movement) by a predetermined amount in a single reciprocating vibration as shown in FIG. It moves backward (backward) by the amount of backward movement, moves in each movement direction by the amount of advancement of the difference, and cooperatively sends the cutting tool 130 to the workpiece W in the Z axis direction as the processing feed direction.

The machine tool 100 is rotated by one rotation of the main spindle, that is, the main spindle, while the cutting tool 130 reciprocates along the processing feed direction by the Z axis direction feed mechanism 160, the X axis direction feed mechanism 150, and the Y axis direction feed mechanism. The workpiece W is processed by being fed in the processing feed direction with the sum of the advance amounts when the phase changes from 0 ° to 360 ° as the feed amount.
The surface on which the cutting tool 130 has machined the workpiece W and has been machined is the workpiece machining surface W1.

With the work W rotated, the spindle stock 110A (spindle 110) or the cutting tool stand 130A (cutting tool 130) moves while oscillating reciprocally, and the cutting tool 130 performs external cutting on the work W into a predetermined shape. In the case, the circumferential surface of the work W is cut in a sinusoidal manner as shown in FIG.
In the virtual line (one-dot chain line) passing through the valley of the sinusoidal waveform, the amount of change in position when the spindle phase changes from 0 ° to 360 ° indicates the feed amount.
As shown in FIG. 4, the frequency N of the spindle head 110A (spindle 110) or the cutting tool stand 130A per one rotation of the workpiece W is 3.5 times (frequency N = 3.5). Do.

  In this case, the lowest point of the valley of the phase of the circumferential shape of the workpiece circumferential surface to be turned by the cutting tool 130 of the n + 1th rotation (n is an integer of 1 or more) (dotted line waveform The position of the peak of the peak of the graph is the direction of the main spindle phase (the peak of the peak of the peak of the peak of the solid waveform graph) with respect to the position of the lowest point of the valley of the phase of the shape turned by the cutting tool 130 for the nth rotation. Shift in the horizontal axis direction).

Thereby, the cutting portion at the time of forward movement of the cutting tool 130 and the cutting portion at the time of backward movement partially overlap, and a portion already cut at the nth rotation in the cutting portion of the n + 1th rotation of the work peripheral surface. There is a so-called idling operation in which the cutting tool 130 does not cut the workpiece W in the machining feed direction during vibration cutting.
The chips generated from the workpiece W at the time of cutting are sequentially divided by the idling operation.
The machine tool 100 can smoothly carry out outer shape cutting of the workpiece W while separating chips by the reciprocating vibration along the cutting feed direction of the cutting tool 130.

In the case where chips are sequentially divided by the reciprocation vibration of the cutting tool 130, a cut portion at the n-th rotation may be included in the cutting portion at the n + 1-th rotation of the work circumferential surface.
In other words, the trajectory of the cutting tool 130 at the time of backward movement in the n + 1th rotation (n is an integer of 1 or more) of the circumferential surface of the workpiece may reach the trajectory of the cutting tool 130 at the nth rotation of the circumferential surface of the workpiece.
As shown in FIG. 4, the phases of the shapes to be turned by the cutting tool 130 in the n + 1th rotation and the nth rotation work W are not required to be in phase (in phase), and it is not necessary to invert 180 °.

For example, the frequency N can be 1.1, 1.25, 2.6, 3.75 or the like.
It is also possible to set so as to perform less than one vibration (0 <frequency N <1.0) in one rotation of the work W.
In this case, the main shaft 110 rotates for one or more rotations per one vibration.

In the machine tool 100, an operation command from the control unit C1 is issued in predetermined command time units.
The reciprocating vibration of the spindle stock 110A (spindle 110) or the cutting tool pedestal 130A (cutting tool 130) can be operated at a predetermined frequency based on the command time unit.
For example, in the case of the machine tool 100 capable of sending 250 commands per second by the control unit C1, the operation command from the control unit C1 is lined at 1 ÷ 250 = 4 (ms) cycle (every command time unit). It will be.

As shown in FIG. 5, the control unit C1 of this embodiment is a cutting direction when the cutting tool 130 does not cut the workpiece W in the Z-axis direction as a machining feed direction during vibration cutting, that is, when it becomes an idle operation. The cutting tool 130 is reciprocated so as to move relative to the cutting tool 130 in the Y-axis direction which is a direction intersecting the X-axis direction.
That is, the control unit C1 controls the Y-axis direction feeding mechanism (not shown) to move the cutting tool 130 relative to the workpiece W in the Y-axis direction which is a direction intersecting the cutting direction when dividing chips. .
As a result, as shown in FIG. 6A, assuming that the angle of the blade surface formed by the surface perpendicular to the work processing surface W1 and the blade surface of the blade 131 in the blade 131 of the cutting tool 130 is the blade surface angle, The blade surface angle α1 is 0 ° when the cutting tool 130 processes the unworked portion W2 of the workpiece during vibration cutting and chips are generated. However, FIG. As shown in), the blade surface angle α2 is larger than α1.

  Here, as shown in FIGS. 7A and 7B, assuming that the outflow angle of the chip K (K ′) with respect to the workpiece processing surface W1 is β, as shown in FIG. 7A for reference, When the blade surface angle α 1 = 0 °, the outflow angle β 1 with respect to the work machined surface W 1 of chips K ′ (not generated in this embodiment) generated by cutting from the work unmachined portion W 2 was 0 ° Just before the chips are divided, as shown in FIG. 7 (B), when the blade surface angle α 2, the divided chips K are directed away from the workpiece processing surface W 1 by the force received from the rake surface of the cutting edge 131 The outflow angle β2 of the chip K becomes larger than β1.

As a result, as shown in FIG. 8, since the cut chips K can be made to flow away from the work processing surface W1, damage to the work processing surface W1 by the chips K can be avoided.
After that, the control unit C1 moves the cutting tool 130 to a position before moving the cutting tool 130 to a position before moving in a direction crossing the cutting direction in the Y-axis direction which is a direction intersecting the cutting direction. The processing point W2 is processed, and the vibration means is controlled to repeat the above-described operation.

Note that the cutting tool 130 does not cut the workpiece W in the Z-axis direction as the machining feed direction during vibration cutting, that is, when the idling operation is performed, the cutting tool 130 is moved in the Y-axis direction to move the cutting tool 130 to the workpiece W It may be completely separated from
As a result, while the cutting tool 130 is completely separated from the workpiece W during the idling operation, the cutting tool 130 does not receive stress from the workpiece W.
As a result, it is possible to reduce the load on the cutting tool 130, to avoid breakage of the cutting edge 131 of the cutting tool 130, and to prolong the life of the cutting tool 130.
Furthermore, since the cutting oil is easily introduced between the cutting edge 131 of the cutting tool 130 and the work W, the effect of the cutting oil can be enhanced.

In the present embodiment, as shown in FIG. 4 described above, the trajectory of the cutting tool 130 at the time of backward movement of the control unit C1 at the n + 1th rotation (n is an integer of 1 or more) of the workpiece W is n revolutions of the workpiece W. Although control is made to cross the trajectory of the cutting tool 130 in the eye, it may be reached without crossing.
In other words, control was performed so that the cutting portion at the time of forward movement and the cutting portion at the time of backward movement overlap, but the cutting portion at the time of forward movement and the cutting portion at the time of backward movement were in contact with each other May be
As a result, the cutting portion at the time of backward movement is theoretically included as a “point” in the cutting portion at the time of forward movement of the cutting tool 130 in one vibration, and the cutting tool 130 does not cut the workpiece W during the backward movement. The chipping movement generated from the workpiece W at the time of cutting is divided by the above-mentioned idling movement (the point at which the cutting part at the time of forward movement and the cutting part at the time of backward movement are in contact). Be done.

100 · · · Machine tool 110 · · · Spindle 110A · · · Headstock 120 · · · Chuck 130 · · · Cutting tool 130A · · · Cutting tool stand 131 · · · Cutting edge 150 · · · X axis direction feed mechanism 151 ... Base 152 ... X-axis direction guide rail 153 ... X-axis direction feed table 154 ... X-axis direction guide 155 ... Linear servomotor 155a ... Mover 155b ... Stator 160 ... Z axis direction feeding mechanism 161 ... Base 162 ... Z axis direction guide rail 163 ... Z axis direction feed table 164 ... Z axis direction guide 165 ... Linear servomotor 165a ... Mover 165b: Stator C: Control device C1: Control unit W: Work piece W1: Work piece processing surface W2: Work piece Machining spot

Claims (3)

A workpiece holding means for holding a workpiece, a tool rest for holding a cutting tool for cutting the workpiece, and a relative movement between the workpiece holding means and the tool rest for at least a cutting direction of the cutting tool relative to the workpiece and a feed means for feeding operating in the processing-feed direction crossing the cutting direction, a vibrating means for relatively vibrating the and the tool rest the workpiece holding means along said machining feed direction, and said workpiece and cutting tool And rotation means for relatively rotating
A cutting portion in a forward movement of the round trip vibration, with overlapping and cutting portion in a backward and sends relatively to the processing feed direction while reciprocally vibrate along said cutting tool in the working feed direction As described above, drive control of the vibration means and the rotation means is linkedly controlled, and the relative rotation between the work and the cutting tool and the feeding operation accompanied by the reciprocating vibration in the processing feed direction of the cutting tool with respect to the work , a machine tool for executing the machining of the workpiece while cutting the chips in duplicate portion,
There is provided moving means for moving the cutting tool relative to the work in a direction intersecting the cutting direction and the processing feed direction when dividing the chips .
A machine tool according to claim 1, wherein the moving means performs the movement at the start of overlapping of the cutting portions at the forward movement and at the backward movement . The machine tool according to claim 1, wherein the moving means is configured to move the cutting tool along the rotation direction of the rotating means. A workpiece holding means for holding a workpiece, a tool rest for holding a cutting tool for cutting the workpiece, and a relative movement between the workpiece holding means and the tool rest for at least a cutting direction of the cutting tool relative to the workpiece and a feed means for feeding operating in the processing-feed direction crossing the cutting direction, a vibrating means for relatively vibrating the and the tool rest the workpiece holding means along said machining feed direction, and said workpiece and cutting tool Provided on a machine tool provided with rotation means for relatively rotating
A cutting portion in a forward movement of the round trip vibration, with overlapping and cutting portion in a backward and sends relatively to the processing feed direction while reciprocally vibrate along said cutting tool in the working feed direction As described above, drive control of the vibration means and the rotation means is linkedly controlled, and the relative rotation between the work and the cutting tool and the feeding operation accompanied by the reciprocating vibration in the processing feed direction of the cutting tool with respect to the work , a control device of the machine tool for executing the machining of the workpiece while cutting the chips in duplicate portion,
There is provided moving means for moving the cutting tool relative to the work in a direction intersecting the cutting direction and the processing feed direction when dividing the chips .
The control device for a machine tool, wherein the moving means performs the movement at the start of overlapping of the cutting portions at the forward movement and at the backward movement .