JP6517060B2 - 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 (paragraph 0049, paragraph 0053, refer to Figure 7)

  However, since the conventional machine tool described above performs cutting while cutting off chips by overlapping the cutting portion at the time of forward movement of the reciprocating vibration and the cutting portion at the time of backward movement, the overlapping portion There is a problem that the pattern line of the machined surface of the workpiece generated due to may be noticeable.

  Therefore, the present invention solves the problems of the prior art as described above, that is, the object of the present invention is to surely separate chips generated from a workpiece one after another and generate a noticeable pattern line on the workpiece processing surface It is an object of the present invention to provide a machine tool capable of suppressing

The invention according to claim 1 relates to 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 the workpiece. The feed means for feeding the cutting tool in a predetermined feed direction, the work holding means and the tool post relatively vibrate, and the cut portion at the time of forward movement and the cut portion at the time of backward movement And rotating means for relatively rotating the workpiece and the cutting tool, wherein the relative rotation between the workpiece and the cutting tool, and the processing feed direction of the cutting tool with respect to the workpiece by a feed operation with the reciprocating vibration to, a machine tool that performs the machining of the workpiece, the value interval of the pattern line with each other are formed on the workpiece machining surface of the workpiece predetermined As smaller Ri, by providing the vibration cutting condition setting means for changing the frequency or the feed amount of reciprocating movement of the relative rotation per rotation in performing the machining of the workpiece, to solve the aforementioned problems It is a thing.

In the invention according to claim 2 , in addition to the configuration of the machine tool described in claim 1, the oscillating cutting condition setting means reciprocates oscillation per one rotation of the relative rotation when processing the work is performed. of the Rukoto changing the inclination of the pattern lines is inclined from the original by changing at least one of the frequencies or the feed amount, by which is configured to change the interval between pattern lines, further the problems described above It is a solution.

In the invention according to the third aspect , in addition to the configuration of the machine tool described in the first or second aspect , the vibration cutting condition setting means makes the distance between the pattern lines less than 0.3 mm. By doing this, the above-mentioned problems are further solved.

In the invention according to the fourth 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. The feed means for feeding the tool in a predetermined feed direction, the relative movement between the work holding means and the tool post, the cutting portion at the time of forward movement of the vibration and the cutting portion at the time of backward movement The vibration means to be overlapped, and the rotation means for relatively rotating the work and the cutting tool, the relative rotation between the work and the cutting tool, and the direction of the cutting tool to the work with respect to the work. by a feed operation with reciprocal vibration, a control apparatus of a machine tool that performs the machining of the workpiece, the value interval of the pattern line with each other a predetermined formed workpiece machining surface of the workpiece As smaller, by providing the vibration cutting condition setting means for changing the frequency or the feed amount of reciprocating movement of the relative rotation per rotation in performing the machining of the workpiece, which solve the aforementioned problems It is.

According to the machine tool of the first aspect of the present invention, the vibration cutting condition setting means sets the distance between the pattern lines formed on the workpiece machining surface of the workpiece to change the interval between the pattern lines to make the workpiece machining surface noticeable It is possible to suppress the generation of lines.
Furthermore, since the inclination of the pattern line with respect to the relative rotation direction becomes small and the interval between the pattern lines becomes narrow, the effect of making the pattern line of the work machined surface inconspicuous can be enhanced.

According to the machine tool of the invention according to claim 2 , in addition to the effect exhibited by the invention according to claim 1, the interval between the pattern lines becomes narrow, so the interval between the pattern lines is easily made smaller than the predetermined value. be able to.

According to the machine tool of the invention according to the claims 3, in addition to the effects of the invention according to claim 1 or claim 2, for possible intervals visually recognized ergonomically seen is about 0.3 mm, pattern The pattern lines can be effectively made inconspicuous by setting the distance between the lines to less than 0.3 mm.

According to the controller of the machine tool of the invention according to the fourth aspect , in the controller of the machine tool,
The same effects as the effects of the invention according to claim 1 can be obtained.

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. The figure explaining the inclination of a pattern line, and the space | interval between pattern lines.

The machine tool according to the present invention and the control device for the machine tool are configured such that the distance between pattern lines formed on the workpiece machining surface of the workpiece when machining the workpiece is smaller than a predetermined value. By providing vibration cutting condition setting means for changing the frequency or amount of reciprocating vibration per relative rotation when processing is performed, pattern lines which appear to be inclined with respect to the processing feed direction on the work processing surface The specific embodiment may be any specific one as long as it narrows the interval of and makes the pattern line of the work machined surface inconspicuous.

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
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.

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) per one rotation of the workpiece W or the cutting tool stand 130A is 1.44 times (frequency N = 1.44) as an example. 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 redundantly included in the cutting portion of 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, it is preferable that the phases of the trajectories of the cutting tool 130 in the workpiece W at the (n + 1) th rotation and the nth rotation do not match (the same phase).
For example, the frequency N can be 1.1, 1.25, 2.6, 3.75 or the like.

The part where the locus of the cutting tool 130 at the nth rotation of the work peripheral surface and the locus of the cutting tool 130 at the time of backward movement at the n + 1th overlap is gradually displaced and expanded as the machining progresses in the machining feed direction When W is processed, as shown in FIG. 5, the intersection point of the trajectory of the cutting tool 130 at the n + 1th rotation (n is an integer of 1 or more) of the workpiece W and the trajectory of the cutting tool 130 at the n rotation of the workpiece W For example, a pair of two wires PL connected with a nearby intersection point are inclined with respect to the Z-axis direction which is a processing feed direction, and two one pair PL in the processing feed direction and the next two pair PL When the interval (pitch) A is 0.3 mm or more as a predetermined value, the two-piece line PL connecting the intersections is visually recognized as a pattern line with the naked eye, and the pattern line of the work machined surface becomes noticeable.
In addition, there may be a case where one each of the two-piece set line PL is visually recognized as a pattern line with the naked eye.

In the machine tool 100 of the present embodiment, the control unit C1 and the numerical value setting unit C2 of the control device C are either the feed amount of the cutting tool 130 for the workpiece W per one spindle rotation or the frequency of reciprocating vibration per one spindle rotation. The setting unit is configured to set the parameter as a parameter, and the user sets the feed amount F, the spindle rotational speed, and the vibration number N in the control unit C1 via the numerical value setting unit C2 and the like.
Further, the control unit C1 includes vibration cutting condition setting means for changing and setting the parameter set by the setting means based on the predetermined condition of vibration cutting.

The control unit C1 calculates based on the parameters set by the setting means, etc., and on the workpiece machining surface of the workpiece W, the pattern line interval in the machining feed direction between the pattern lines that appear to be inclined with respect to the machining feed direction It is determined whether the pitch A) is 0.3 mm or more as a predetermined value in the processing feed direction.
Here, the reason why the predetermined value is set to 0.3 mm is that the ergonomically visible interval is about 0.3 mm.
When the pattern line interval A is 0.3 mm or more, the control unit C1 changes either the feed amount F or the frequency N parameter to narrow the pattern line interval A and set the pattern line interval A to a predetermined value. I try to be less than.

Here, assuming that Nr is a value such as 0.5, 1.5, 2.5,..., That is, a value of an integer + 0.5 closest to the value of the frequency, geometrically the pattern line spacing A is
A = F · N / {2Nr (Nr-N)}
And derived.
Also, assuming that the circumference of the work surface is L, geometrically, the inclination K of the pattern line with respect to the main axis rotation direction is
K = F · N / {L (Nr-N)}
And derived.

When the pattern line spacing A is 0.3 mm or more, the control unit C1 changes the frequency N to a smaller value.
As a result, the inclination K of the design line with respect to the main spindle rotation direction is reduced, and the pattern line spacing A in the processing feed direction is narrowed, making it difficult for the individual design lines to be viewed visually.
The control unit C1 may change the feed amount F to a smaller value.
As a result, the inclination K of the design line with respect to the main axis rotation direction becomes smaller and the pattern line spacing A becomes smaller, and the design line of the work machined surface becomes inconspicuous.

  In the present embodiment, it has been described that the feed amount F and the frequency N are set by the vibration cutting condition setting means, but a program processing unit (not shown) in the control device C scans the machining program. Grasp the processing conditions including feed amount F and frequency N, and from that condition determine whether the pattern line interval A is visually recognized by human eyes, and notify it to the processing program creator or Automatic correction may be performed on

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 150 · · · X-axis direction feeding mechanism 151 · · · Base 152 ... X axis direction guide rail 153 ... X axis direction feed table 154 ... X axis direction guide 155 ... linear servo motor 155a ... mover 155b ... stator 160 ... Z axis Direction feed mechanism 161 · · · Base 162 · · · Z axis direction guide rail 163 · · · Z axis direction feed table 164 · · · Z axis direction guide 165 · · · Linear servo motor 165a · · · · mover 165b · · · · Stator A · · · Pattern line spacing C · · · Control device C 1 · · · Control section C 2 · · · Numeric setting section K · · · · Pattern line inclination PL · · · This one set line (pattern-ray)
W · · · Work

Claims (4)

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 in the predetermined processing feed direction with respect to the workpiece A feeding means for feeding operation, a vibrating means for relatively vibrating the work holding means and the tool rest, and overlapping a cutting portion at the time of forward movement of the vibration and a cutting portion at the time of backward movement; A rotating means for relatively rotating the workpiece and the cutting tool;
It is a machine tool which performs processing of the work by relative rotation of the work and the cutting tool, and a feeding operation accompanied by the reciprocating vibration in the processing feed direction of the cutting tool with respect to the work,
The frequency or feed of the reciprocating vibration per rotation of the relative rotation at the time of processing the work such that the distance between the pattern lines formed on the work processing surface of the work is smaller than a predetermined value A machine tool comprising vibration cutting condition setting means for changing an amount . The inclination of the pattern line which is inclined from the original by changing at least one of the vibration number and the feed amount of the reciprocating vibration per one rotation of the relative rotation at the time of executing the processing of the work by changing Rukoto machine tool according to claim 1, which is configured to change the interval between pattern lines. The machine tool according to claim 1 or 2 , wherein the vibration cutting condition setting means is configured to set the distance between the pattern lines to less than 0.3 mm. The cutting tool is fed in a predetermined processing feed direction to the work by relative movement between the work holding means for holding the work, the tool holder for holding the cutting tool for cutting the work, and the work holding means and the tool stand. Feeding means for operating, vibration means for relatively vibrating the work holding means and the tool rest, and overlapping a cutting portion at the time of forward movement of the vibration and a cutting portion at the time of backward movement; A rotating means for rotating the cutting tool relative to each other, 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 relative to the work, A control device for a machine tool that performs machining of the workpiece, wherein
The frequency or feed of the reciprocating vibration per rotation of the relative rotation at the time of processing the work such that the distance between the pattern lines formed on the work processing surface of the work is smaller than a predetermined value A control device for a machine tool, comprising vibration cutting condition setting means for changing an amount .