JP2017013151A - Wire electric discharge machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wire electric discharge machine capable of suppressing displacement of a table in a direction different from the movement direction when moving the table.SOLUTION: A wire electric discharge machine 10 moves a table 11 to which a workpiece W is fixed so as to change the position of the workpiece W with respect to a wire electrode 12. The wire electric discharge machine includes: a saddle 13 on which the table 11 is mounted to be movable forward and backward in an X-axis direction; and a base table 14 on which the saddle 13 is mounted to be movable forward and backward in a Y-axis direction perpendicular to the X-axis direction. The table 11 includes first receiving sections 17 and 18 on a lower side. The saddle 13 includes first guides 21 and 22 slidably connected in a surface contact state of the first receiving sections 17 and 18 and second receiving sections 33 and 34 on an upper side and the lower side, respectively. The base table 14 includes second guides 41 and 42 slidably connected in a surface contact state of the second receiving sections 33 and 34 on the upper side.SELECTED DRAWING: Figure 1

Description

The present invention relates to a wire electric discharge machine that processes a workpiece by electric discharge.

There are two types of wire electric discharge machines that perform machining by electric discharge: one that moves the processing part of the wire electrode with respect to the fixed workpiece, and one that moves the workpiece with respect to the processing part of the fixed wire electrode. A specific example of a wire electric discharge machine for moving a workpiece is described in Patent Document 1.
The wire electric discharge machine of Patent Document 1 moves the table on which the workpiece is fixed in the X-axis direction and the Y-axis direction, and changes the position of the workpiece relative to the wire electrode. Since the position adjustment accuracy of the table has a great influence on the accuracy of processing, the accurate movement of the table is important for increasing the processing accuracy.

Although description is omitted in Patent Document 1, in this type of wire electric discharge machine, the table 100 moves in the X-axis direction and the Y-axis direction by the structure shown in FIG. That is, the slide block 103 provided at the lower portion of the saddle 102 is movably attached to the guide rail 101 along the Y-axis direction, and the table is attached to the guide rail 104 along the X-axis direction provided at the upper portion of the saddle 102. A slide block 105 provided at the bottom of 100 is movably attached. As a result, the table 100 moves in the Y-axis direction as the saddle 102 advances and retracts along the guide rail 101, and the table 100 advances and retracts along the guide rail 104 together with the slide block 105. Move in the direction.

Conventionally, for the slide blocks 103 and 105, linear motion type rolling bearings having a plurality of rolling elements such as balls and rollers are used, and the slide blocks 103 and 105 use the rolling of the rolling elements to guide the guide rail 101, The frictional force generated between the control unit 104 and the table 104 is suppressed, and the table 100 is moved smoothly.
Here, a rolling bearing is a guide rail in which a plurality of balls (balls) provided between a slide block (bearing body) and a guide rail are used as shown in FIG. The slide block moves by rolling along the guide groove formed on the surface. Preload is applied to the ball in a portion in contact with the slide block and the guide rail, and the preload is released by releasing the state of being in contact with the slide block and the guide rail by rolling the ball.
The reason why the combination of the slide block and the guide rail using a direct-acting rolling bearing is adopted is that it is easy to install and has excellent productivity, and that the friction force can be kept low without being affected by the assembly. Can be mentioned.

JP 2004-209622 A JP 2008-279541 A

By the way, in recent years, the required machining accuracy of wire electric discharge machines is increasing. As a result of intensive investigations aimed at improving machining accuracy, the present inventors have displaced the table in a micrometer order in a direction different from the moving direction when moving, and the displacement of the table is improved in machining accuracy. It was confirmed that it had an adverse effect.
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a wire electric discharge machine capable of suppressing displacement of the table in a direction different from the moving direction when the table is moved. .

A wire electric discharge machine according to the present invention that meets the above object is a wire electric discharge machine that moves a table on which a workpiece is fixed and changes the position of the workpiece with respect to a wire electrode. And a base table for placing the saddle in a Y-axis direction perpendicular to the X-axis direction. The table has a first receiving portion on the lower side. And the saddle has a first guide slidably connected in a state where the first receiving portion is in surface contact, and a second receiving portion on the lower side, respectively. The base has an upper second guide that is slidably coupled with the second receiving portion in surface contact.
As a result of numerous verifications, the inventors have found that the structure for moving the table is a direct-acting rolling bearing (that is, when the table is moved, the ball is preloaded and not preloaded). It was found that the use of a bearing having a structure in which the state is repeated causes the table to be displaced in a direction different from the moving direction. This is considered to be because the pressure applied to each rolling element of the linear motion type rolling bearing changes as the table moves. And, by adopting a structure in which the receiving part and the guide are slidably connected in a surface contact state, displacement in a direction different from the moving direction of the table can be suppressed as compared with a structure using a linear motion type rolling bearing. Was recognized.

In the wire electric discharge machine according to the present invention, the first receiving portion includes a first sliding member in surface contact with the first guide, and the second receiving portion is provided on the second guide. A second sliding member in surface contact; a portion in which the first sliding member and the first guide are in surface contact; and the second sliding member and the second guide in surface contact. The part is preferably supplied with lubricating oil.

In the wire electric discharge machine according to the present invention, it is preferable that the discharge port for the lubricating oil is formed in the first and second receiving portions.

In the wire electric discharge machine according to the present invention, it is preferable that the lubricating oil is continuously supplied.

In the wire electric discharge machine according to the present invention, the first receiving portion of the table is slidably connected in a state of surface contact with the first guide of the saddle, and the second receiving portion of the saddle is connected to the base table. Since the second guide is slidably connected in surface contact with the second guide, the table can be moved in a state in which the table is prevented from being displaced in a direction different from the moving direction.

It is explanatory drawing of the wire electric discharge machine which concerns on one embodiment of this invention. It is a partial sectional side view of the wire electric discharge machine. (A), (B) is the bottom view of the table of the same wire electric discharge machine, and the bottom view of the table which concerns on a modification, respectively. It is explanatory drawing which shows the connection of a saddle and a base stand. It is a graph which shows the vibration of the workpiece of a comparative example. 3 is a graph showing vibration of the workpiece of Example 1. (A), (B) is a graph which shows the mode of the movement of the workpiece of Example 2, 3, respectively. It is a graph which shows the dispersion | variation in the process of the workpiece of Examples 2 and 3. FIG. It is explanatory drawing which shows the structure which moves the table of the wire electric discharge machine which concerns on a prior art example.

Next, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention.
As shown in FIG. 1, a wire electric discharge machine 10 according to an embodiment of the present invention moves a table 11 on which a workpiece W is fixed, and changes the position of the workpiece W with respect to the wire electrode 12. Is. Details will be described below.

As shown in FIG. 1, the wire electric discharge machine 10 includes a table 11 on which a workpiece W is fixed, a saddle 13 on which the table 11 is placed so as to be movable back and forth in the X-axis direction, and the saddle 13 in the Y-axis direction. A base table 14 is mounted so as to be able to advance and retreat. Here, the X axis and the Y axis are respectively virtual axes arranged horizontally, and the X axis and the Y axis are orthogonal to each other. That is, the Y-axis direction is perpendicular (right angle) to the X-axis direction.
The workpiece W is fixed to the table 11 by the support member 15, and a processing tank 16 in which a processing liquid (not shown) is stored is placed on the table 11. The workpiece W and the support member 15 are accommodated in the processing tank 16 and immersed in the processing liquid in the processing tank 16.

As shown in FIGS. 1, 2, and 3A, the rectangular table 11 has a groove-shaped receiving portion 17 (first) formed on the negative side on the Y axis direction negative side. 1 receiving portion) and a groove-shaped receiving portion 18 (first receiving portion) formed on the Y axis direction positive side (one side). The receiving portions 17 and 18 are formed along the X-axis direction, respectively. As shown in FIGS. 2 and 3A, the groove-shaped receiving portions 17 and 18 have sliding members 19 and 20 that suppress friction. The (first sliding member) is fixed by an adhesive. That is, the table 11 includes receiving portions 17 and 18, and the receiving portions 17 and 18 include sliding members 19 and 20, respectively.

In the present embodiment, as shown in FIG. 3 (A), the sliding members 19 and 20 are synthetic resins that are long along the X-axis direction, and are molded by mixing Teflon (registered trademark) and gunmetal particles. ing. As shown in FIGS. 2 and 3A, the sliding member 19 has a plate-like horizontal portion 19a arranged horizontally and a plate-like shape formed continuously on the Y axis direction positive side of the horizontal portion 19a. The sliding member 20 includes a horizontally extending plate-like horizontal portion 20a and a plate-like hanging portion 20b continuously formed on the Y axis direction negative side of the horizontal portion 20a. .
In addition, in FIG. 1, description of the sliding members 19 and 20 is abbreviate | omitted.

As shown in FIGS. 2 and 4, the saddle 13 has convex guides 21 and 22 (first guides) on the upper side that are long in the X-axis direction. A guide 21 provided on the negative side in the Y-axis direction of the saddle 13 is fitted into the receiving portion 17 so as to be slidable on the receiving portion 17 while being in surface contact with the horizontal portion 19a and the hanging portion 19b of the sliding member 19. It is connected. A guide 22 provided on the positive side in the Y-axis direction of the saddle 13 is fitted into the receiving portion 18 so as to be slidable on the receiving portion 18 while being in surface contact with the horizontal portion 20a and the hanging portion 20b of the sliding member 20. It is connected.

The guide 21 is longer in the X-axis direction than the receiving portion 17, and on the upper side, a planar portion 21 a that makes surface contact with the horizontal portion 19 a of the sliding member 19 and a planar portion 21 b that makes surface contact with the hanging portion 19 b of the sliding member 19. And. The guide 22 is longer in the X-axis direction than the receiving portion 18, and on the upper side, a planar portion 22 a that makes surface contact with the horizontal portion 20 a of the sliding member 20 and a planar portion 22 b that makes surface contact with the hanging portion 20 b of the sliding member 20. And.

As shown in FIG. 2, a motor 24 to which a screw shaft 23 is connected is fixed to the saddle 13, and a nut 25 fixed to the table 11 is attached to the screw shaft 23 arranged in the X-axis direction. Yes. The screw shaft 23 is supported by a bearing (not shown).
The driving direction of the motor 24 can be switched, and the screw shaft 23 can be rotated left and right. The nut 25 moves to the X axis direction positive side (one side) along the screw shaft 23 when the screw shaft 23 rotates counterclockwise, and rotates along the screw shaft 23 when the screw shaft 23 rotates clockwise. Move to the negative side (other side) in the axial direction.

The table 11 is guided by the guides 21 and 22 by the drive of the motor 24 and advances and retreats in the X-axis direction together with the nut 25. The table 11 and the saddle 13 are connected in a state where the sliding member 19 and the guide 21 are in contact with the horizontal portion 19a, the flat portion 21a, the hanging portion 19b, and the flat portion 21b, respectively, and the frictional force is suppressed. 20 and the guide 22 are connected in a state in which the horizontal portion 20a and the planar portion 22a and the hanging portion 20b and the planar portion 22b are in surface contact with each other and the frictional force is suppressed.

Here, the guides 21 and 22 are hardened steel having a hardness of HS 65 to 75, and the planar portions 21a and 21b and the planar portions 22a and 22b are reduced in surface roughness by polishing (in this embodiment, the surface Roughness Ra is 0.3 μm or less) and flattening (in this embodiment, flatness over the entire length in the X-axis direction is 10 μm or less), and the sliding members 19 and 20 are respectively connected to the guides 21 and 22. Since the contact portion is processed uniformly, the frictional force between the guide 21 and the sliding member 19 and the frictional force between the guide 22 and the sliding member 20 are reduced. Therefore, the table 11 can move smoothly in the X-axis direction with respect to the saddle 13.

Further, as shown in FIG. 1, an oil supply means 26 for feeding lubricating oil to the table 11 is connected to the table 11 via a pipe 27. The table 11 is connected to the pipe 27 as shown in FIG. The flow path 28 connected to is provided. And the discharge ports 29 and 30 of the lubricating oil which are the exit side of the flow path 28 are each arrange | positioned at the receiving parts 17 and 18, as shown to FIG. 2, FIG. 3 (A).

As shown in FIG. 3A, the sliding members 19 and 20 of the present embodiment are provided with grooves 31 and 32 that are open on the lower side, respectively. The groove 31 is provided at the center in the width direction (Y-axis direction) of the horizontal portion 19a of the sliding member 19 with one linear portion 31a formed along the X-axis direction and a linear portion provided along the Y-axis direction. A plurality of straight portions 31b orthogonal to 31a, and the groove 32 is also formed in the center of the horizontal portion 20a of the sliding member 20 in the width direction (Y-axis direction) along the X-axis direction. And it is provided with the some linear part 32b provided along the Y-axis direction and orthogonal to the linear part 32a. A plurality of discharge ports 29 are provided at a predetermined pitch in the X-axis direction at the bottom of the groove 31 (ie, the sliding member 19), and a plurality of discharge ports are provided at the bottom of the groove 32 (ie, the sliding member 20). 30 are provided at a predetermined pitch in the X-axis direction.

The groove provided in the horizontal portion of the sliding member is not limited to the shape of the grooves 31 and 32. For example, as shown in FIG. 3B, a shape in which a plurality of Z (alphabet Z) are connected. It may be a groove.
Note that a lubricant outlet and a groove are also formed in the drooping portion 19 b of the sliding member 19 and the drooping portion 20 b of the sliding member 20.

The lubricating oil sent from the oil supply means 26 passes through the pipe 27 and the flow path 28 and is sent out from the plurality of discharge ports 29 and 30. Lubricating oil that has exited from the plurality of discharge ports 29 travels along the groove 31 and is supplied from the entire groove 31 to the portion where the sliding member 19 and the guide 21 are in surface contact. Along the groove 32, the sliding member 20 and the guide 22 are supplied from the entire groove 32 to a surface contact portion. The frictional force generated on the contact surface between the sliding member 19 and the guide 21 and the frictional force generated on the contact surface between the sliding member 20 and the guide 22 are reduced by the supplied lubricating oil.

In the present embodiment, in the horizontal portion 19 a of the sliding member 19, a plurality of convex portions that are in surface contact with the flat portion 21 a of the guide 21 in the region excluding the groove 31, and are recessed by 2 to 3 μm from the convex portions ( That is, a plurality of recesses (located above) are provided uniformly. Lubricating oil is stably supplied to the contact region between the horizontal portion 19a of the sliding member 19 and the flat portion 21a of the guide 21 using the plurality of recesses as flow paths. The total area of the plurality of convex portions is 15 to 25% of the entire area excluding the groove 31 of the horizontal portion 19 a of the sliding member 19. The same applies to the horizontal portion 20a of the sliding member 20 in that a plurality of convex portions and a plurality of concave portions are provided.

Here, the lubricant outlets 29 and 30 can be provided not in the receiving portions 17 and 18 but in the guides 21 and 22, respectively. However, when provided in the receiving portions 17 and 18, when provided in the guides 21 and 22, respectively. In comparison, the lubricating oil can be efficiently supplied to the entire region where the receiving portion 17 and the guide 21 are in contact and the entire region where the receiving portion 18 and the guide 22 are in contact. When the lubricant outlets 29 and 30 are provided in the guides 21 and 22, the flow path 28 connected to the oil supply means 26 via the pipe 27 is provided in the saddle 13.
In addition, in the present embodiment, since the lubricating oil is continuously supplied, the occurrence of stick slip can be stably suppressed as compared with the case where the lubricating oil is supplied intermittently.

Further, as shown in FIGS. 1, 2, and 4, the saddle 13 has groove-shaped receiving portions 33 and 34 (second receiving portions) on the lower side. The receiving portion 33 is provided along the Y-axis direction on the positive side of the saddle 13 in the X-axis direction, and the receiving portion 34 is provided along the Y-axis direction on the negative side of the saddle 13 in the X-axis direction. As shown in FIGS. 2 and 4, the receiving portions 33 and 34 are formed by mixing Teflon (registered trademark) and gunmetal particles at the bottom and sliding members 37 and 38 (second Sliding members).
The sliding member 37 includes a plate-like horizontal portion 37a and a hanging portion 37b continuously formed on the X-axis direction negative side of the horizontal portion 37a. The sliding member 38 includes a plate-like horizontal portion 38a and a horizontal portion. A drooping portion 38b formed continuously on the X axis direction positive side of 38a is provided.

The base 14 has guides 41 and 42 (second guides) that are long along the Y-axis direction on the upper side. As shown in FIG. 4, the guides 41 and 42 protruding upward are provided at an interval in the X-axis direction. The guide 41 has a flat surface portion 41 a that is in surface contact with the horizontal portion 37 a of the sliding member 37 and a flat surface portion 41 b that is in surface contact with the hanging portion 37 b of the sliding member 37, and the guide 42 is horizontal to the sliding member 38. The flat portion 42a is in surface contact with the portion 38a, and the flat portion 42b is in surface contact with the hanging portion 38b of the sliding member 38.

2 and 4, the receiving portion 33 slides on the guide 41 in a state where the horizontal portion 37a and the hanging portion 37b of the sliding member 37 are in surface contact with the flat portions 41a and 41b of the guide 41, respectively. The receiving portion 34 is slidably connected to the guide 42 in a state where the horizontal portion 38a and the hanging portion 38b of the sliding member 38 are in surface contact with the flat portions 42a and 42b of the guide 42, respectively. Yes.

As shown in FIG. 1, an oil supply means 26 is connected to the saddle 13 via a pipe 27, and the pipe 27 is connected to a flow path 46 formed in the saddle 13 as shown in FIG. Yes. The sliding members 37 and 38 have the same shape as that of the groove 31 including one linear portion along the Y-axis direction at the center in the X-axis direction and a plurality of linear portions provided along the X-axis direction. A plurality of outlets 47 for the lubricating oil on the outlet side of the pipe 27 are formed in the grooves (that is, the receiving portions 33 and 34) of the sliding members 37 and 38, respectively.

Lubricating oil sent from the oil supply means 26 to the flow path 46 via the pipe 27 passes through a groove from the discharge port 47 formed in the sliding member 37, and the sliding member 37 and the guide 41 are in surface contact. It is supplied to the portion, and is supplied from the discharge port 47 formed in the sliding member 38 to the portion where the sliding member 38 and the guide 42 are in surface contact through the groove.
In the present embodiment, even in the horizontal portion 37a of the sliding member 37, a plurality of convex portions that are in surface contact with the flat portion 41a of the guide 41 in the region excluding the groove, and are recessed by 2 to 3 μm from the convex portions ( That is, since a plurality of recesses (which are located above) are provided uniformly, the lubricating oil has the plurality of recesses as flow paths, and the horizontal portion 37a of the sliding member 37 and the flat portion 41a of the guide 41. The contact area is stably supplied. The same applies to the horizontal portion 38a of the sliding member 38 in that the plurality of convex portions and the plurality of concave portions are provided.

Similarly to the guides 21 and 22, the guides 41 and 42 are hardened steel having a hardness of HS 65 to 75, and the planar portions 41a and 41b and the planar portions 42a and 42b are reduced in surface roughness by polishing ( In the present embodiment, surface roughness Ra is 0.3 μm or less) and flattening (in this embodiment, flatness over the entire length in the Y-axis direction is 10 μm or less), and the sliding members 37 and 38 are The portions that contact the guides 41 and 42 are processed uniformly. Therefore, the guide 41 and the receiving portion 33 are connected in a state where the frictional force between the guide 41 and the sliding member 37 is suppressed, and the guide 42 and the receiving portion 34 are also connected to the friction between the guide 42 and the sliding member 38. It is connected in a state where the force is suppressed.

As shown in FIG. 2, a motor 49 to which a screw shaft 48 is coupled is fixed to the base 14, and the screw shaft 48 arranged in the Y-axis direction has a saddle as shown in FIGS. 2 and 4. A nut 50 fixed to 13 is mounted. The screw shaft 48 is supported by a bearing (not shown).
The motor 49 can rotate the screw shaft 48 clockwise and counterclockwise, and the nut 50 moves to the Y axis direction positive side (one side) along the screw shaft 48 when the screw shaft 48 rotates right. When the screw shaft 23 rotates counterclockwise, it moves along the screw shaft 48 to the Y axis direction negative side (other side).

As shown in FIG. 1, a long column 51 is connected to the base table 14, and a slide block 53 is mounted on the upper side of the column 51 so as to be able to advance and retreat on a guide 52 arranged in the Y-axis direction. Is placed. A support block 54 that is movable in the X-axis direction with respect to the slide block 53 is attached to the slide block 53, and an elevating member 55 that moves up and down with respect to the support block 54 is attached to the support block 54. . In FIG. 1, description of drive sources that move the slide block 53, the support block 54, and the elevating member 55 is omitted.

An upper wire guide 56 is fixed to the elevating member 55, and a lower wire guide 58 fixed to the lower side of the upper wire guide 56 is attached to the support member 57 fixed to the column 51. The upper wire guide 56 moves by adjusting the positions of the slide block 53, the support block 54 and the elevating member 55. The wire electrode 12 is supplied from a wire supply means (not shown) and is supported in a stretched state by an upper wire guide 56 and a lower wire guide 58.
In FIG. 1, the description of the upstream portion of the wire electrode 12 from the upper wire guide 56 and the downstream portion of the lower wire guide 58 are omitted.

The angle of the stretched portion between the upper wire guide 56 and the lower wire guide 58 of the wire electrode 12 with respect to the workpiece W is changed by the movement of the upper wire guide 56.
The workpiece W is mainly processed by changing the position of the workpiece W with respect to the portion between the upper wire guide 56 and the lower wire guide 58 of the wire electrode 12 by adjusting the position of the table 11. Then, by adjusting the angle of the stretched portion between the upper wire guide 56 and the lower wire guide 58 of the wire electrode 12, the workpiece W can be tapered.

Next, an experiment conducted for confirming the effect of the present invention will be described.
In the first experiment, the table to which the workpiece is fixed is moved, and the workpiece is orthogonal to the direction of travel of the table (hereinafter also simply referred to as “travel direction”) (hereinafter simply “orthogonal”). The amplitude (the width of displacement) oscillating in the “direction”) was measured. The amplitude is measured by bringing a direct-acting rolling bearing into contact with the guide and connecting the receiving portion to the guide so that the receiving portion can be moved, and connecting the receiving portion to the guide so as to be slidable. This was carried out for each of Example 1. The experimental results of the comparative example and Example 1 are shown in FIGS. 5 and 6, respectively.

In the graphs of FIGS. 5 and 6, the horizontal axis indicates the amount of movement of the workpiece in the traveling direction, and the vertical axis indicates the amplitude of the workpiece in the orthogonal direction. The graphs of FIGS. 5 and 6 have the same vertical scale.
D1 in FIG. 5 and D2 in FIG. 6 are the amplitude of one vibration of the workpiece in the comparative example and the amplitude of one vibration of the workpiece in Example 1, respectively, and D1 = 0.25 μm, D2 = 0.05 μm. Needless to say, the smaller the amplitude, the higher the machining accuracy.
From the experimental results, it is clear that the amplitude of Example 1 is smaller than that of the comparative example. Therefore, it was confirmed that Example 1 can be processed in a state in which vibration is suppressed as compared with the comparative example.

In the second experiment, a work piece was worked on Example 2 in which lubricating oil was intermittently supplied to a portion where the sliding member and the guide are in surface contact, and Example 3 in which lubricating oil was continuously supplied. We compared the state of movement. Specifically, after the workpiece is moved forward by 3.75 μm, the movement of the workpiece when a command signal for moving backward by 3.75 μm is given to the motor. The output is a graph in which the vertical axis indicates the amount of movement of the workpiece. The graphs corresponding to Examples 2 and 3 are as shown in FIGS. 7A and 7B, respectively. In Example 2, lubricating oil was supplied every 5 minutes.

In the graphs of FIGS. 7A and 7B, an increase in the movement amount means advancement of the workpiece, and a decrease in the movement amount means retraction of the workpiece. D3 and D4 represent the total advance distance of the workpiece in Example 2 and the total advance distance of the workpiece in Example 3, respectively. D3 = 2.54 μm and D4 = 3.54 μm. . Therefore, it was confirmed that the workpiece in Example 3 has advanced by a distance close to the target value as compared with Example 2. Also in the backward movement of the workpiece, the workpiece moved by a distance closer to the target value in the third embodiment than in the second embodiment.

In the second experiment, the unit feed amount of the table by the motor is set to 0.25 μm, and when the workpiece is moved forward by 3.75 μm (the same goes backward), the table unit feed is made 15 times in total. The control that performs was performed by a motor. Therefore, when the workpiece performs the target movement, there are 15 steps having the same size in the graph.

In this regard, in the graph of Example 3, there are 15 steps in each region corresponding to the advance and retreat of the workpiece, whereas in the graph of Example 2, it corresponds to the advance of the workpiece. There were 14 steps in the region. This is considered to be because stick slip occurred in the part indicated by the arrow in Example 2 as shown in FIG.
Furthermore, the variation in the size of each step in the graph is smaller in Example 3 than in Example 2, and in Example 3, the workpiece can be moved more stably than in Example 2. It was confirmed that.

In the third experiment, 30 workpieces were machined according to Examples 2 and 3 respectively, and variations in machining dimensions were measured. In the graph of FIG. 8 in which the measurement result is output, the vertical axis indicates the variation in the machining dimension of each workpiece when the machining dimension of the first workpiece is used as a reference (machining dimension = 0 μm). . Square points and circle points in the graph indicate the measured values of Example 2 and the measured values of Example 3, respectively.

From the experimental results, the variation in the processing dimension of each workpiece is generally smaller in Example 3 than in Example 2, and further, even in the difference between the maximum value and the minimum value of the workpiece after processing. Example 3 = 0.7 μm, Example 2 = 1.2 μm, and Example 3 was about 58% of Example 2. Therefore, it was confirmed that Example 3 can be processed with higher accuracy than Example 2.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and all changes in conditions and the like that do not depart from the gist are within the scope of the present invention.
For example, the numbers of the first and second receiving portions and the first and second guides are not limited.
Further, the first and second sliding members are not necessarily required, and supply of lubricating oil is not always necessary.
And when supplying lubricating oil, it is preferable to supply lubricating oil continuously, but you may be made intermittently.

10: Wire electric discharge machine, 11: Table, 12: Wire electrode, 13: Saddle, 14: Base stand, 15: Support member, 16: Processing tank, 17, 18: Receiving part, 19: Sliding member, 19a: Horizontal part, 19b: hanging part, 20: sliding member, 20a: horizontal part, 20b: hanging part, 21: guide, 21a, 21b: flat part, 22: guide, 22a, 22b: flat part, 23: screw shaft , 24: motor, 25: nut, 26: oil supply means, 27: piping, 28: flow path, 29, 30: discharge port, 31: groove, 31a, 31b: linear portion, 32: groove, 32a, 32b: Linear part, 33, 34: receiving part, 37: sliding member, 37a: horizontal part, 37b: hanging part, 38: sliding member, 38a: horizontal part, 38b: hanging part, 41: guide, 41a, 41b: Plane portion, 42: guide, 42a, 42b: Surface part, 46: flow path, 47: discharge port, 48: screw shaft, 49: motor, 50: nut, 51: column, 52: guide, 53: slide block, 54: support block, 55: lifting member, 56: Upper wire guide, 57: support member, 58: lower wire guide, W: workpiece

Claims (4)

In a wire electric discharge machine that moves the table on which the workpiece is fixed and changes the position of the workpiece relative to the wire electrode,
A saddle for placing the table so as to be movable back and forth in the X-axis direction; and a base table for placing the saddle so as to be able to advance and retreat in the Y-axis direction perpendicular to the X-axis direction;
The table has a first receiving portion on the lower side, and the saddle has a first guide on the upper side and a second guide that is slidably connected with the first receiving portion in surface contact. The base is provided with a second guide slidably connected to the upper side in a state where the second receiving part is in surface contact. Wire electric discharge machine. 2. The wire electric discharge machine according to claim 1, wherein the first receiving portion includes a first sliding member that is in surface contact with the first guide, and the second receiving portion is the second guide. 3. A second sliding member in surface contact with the first sliding member and the first guide in surface contact with each other, and the second sliding member and the second guide in surface contact with each other. A wire electric discharge machine characterized in that a lubricating oil is supplied to a portion to perform. 3. The wire electric discharge machine according to claim 2, wherein the lubricating oil discharge port is formed in the first and second receiving portions. 4. The wire electric discharge machine according to claim 2, wherein the lubricating oil is continuously supplied.

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