JP2632627B2 - Wire electric discharge machining - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire electric discharge machining method. In particular, the thickness of the cutting edge is thin, and the thickness of the main body is thick,
The present invention relates to a wire electric discharge machining method provided with an R portion between a side surface of a cutting edge and a main body portion and suitable for manufacturing a scraping punch tool.

[0002]

2. Description of the Related Art Conventionally, a scraping punch tool has been manufactured by grinding using a disk-shaped grinder grindstone or electric discharge machining using a rod-shaped electrode.

[0003]

However, in the manufacture of a scraping punch tool by grinding, since the workpiece is in contact with the grindstone, dimensional changes due to frictional heat and dimensional changes due to frictional resistance are likely to occur. In order to prevent these dimensional changes, a work is required to be received, and an operator's unique technology is required. On the other hand, in the production of a scraping punch tool by electric discharge machining, it is necessary to make electrodes and to set electrodes accurately.

[0004] It is an object of the present invention to solve the above-mentioned problems, and to provide a processing method having high dimensional accuracy and simple manufacturing setup.

[0005]

SUMMARY OF THE INVENTION The object of the present invention is to provide a wire electric discharge machining method according to claim 1, that is, a disk-shaped rotating method for supporting a wire from one side at an intermediate position between an upper wire guide portion and a lower wire guide portion. A guide, wherein the thickness of the circumferential end of the rotary guide is equal to the wire diameter, the thickness increases toward the center, and the taper angle is 15 to 45 °. From the upper wire guide portion to the rotary guide in a vertical straight line, the wire is supported in an arc shape by the circumferential end of the rotary guide, and the wire is further supported from the rotary guide to the lower wire guide. Up to the horizontal straight line, arrange the vertical straight wire, the arcuate wire and the horizontal straight wire in the same plane, The while traveling to retract from the upper wire guide portion to the drawer the rotary guide through along the circumferential edge the lower wire guide ear,
The vertical linear wire is kept perpendicular to the cutting edge of the workpiece, and the vertical linear wire and the arcuate wire and the workpiece are relatively moved while being discharged while being discharged. This is achieved by a wire electric discharge machining method, wherein a side surface of a cutting edge and an R portion in contact therewith are simultaneously processed on a workpiece.

Another object of the present invention is to provide a wire electric discharge machining method according to claim 2, that is, a disk-shaped fixed guide for supporting a wire from one side at an intermediate position between an upper wire guide portion and a lower wire guide portion. The thickness of the circumferential end of the fixed guide is equal to the diameter of the wire, and the thickness increases toward the center, and the taper angle is 15 mm.
Using a fixed guide that is ~ 45 °, the wire is stretched vertically straight from the upper wire guide section to the fixed guide, and then the wire is supported in an arc shape by the circumferential end of the fixed guide, Further, the wire is stretched in a horizontal straight line from the fixed guide to the lower wire guide, and the vertical linear wire, the arc-shaped wire, and the horizontal linear wire are arranged in the same plane, and the wire is disposed. While pulling out from the upper wire guide portion and running along the circumferential end of the fixed guide to pull into the lower wire guide, the vertical linear wire is kept perpendicular to the cutting edge of the workpiece,
The vertical straight wire and the arc-shaped wire and the workpiece are discharged and relatively moved while being discharged, thereby simultaneously processing the cutting edge side surface and the R portion in contact with the workpiece. This is also achieved by a wire electric discharge machining method.

Further, the object is a wire electric discharge machining method according to claim 3, that is, a partially arc-shaped fixed guide for supporting a wire from one side at an intermediate position between an upper wire guide portion and a lower wire guide portion. Then, the thickness of the end of the arc-shaped portion of the fixed guide is equivalent to the wire diameter, the thickness increases toward the center, using a fixed guide having a taper angle of 15 to 45 °,
The wire is stretched in a vertical straight line from the upper wire guide portion to the fixed guide, and subsequently, the wire is supported in an arc shape by a circumferential end of the fixed guide, and further,
The wire is stretched in a horizontal straight line from the fixed guide to the lower wire guide, and the vertical linear wire, the arc-shaped wire, and the horizontal linear wire are arranged in the same plane, and the wire is placed in the upper portion. While pulling out from the wire guide portion and running along the circumferential end of the fixed guide and pulling into the lower wire guide, the vertical linear wire is kept perpendicular to the cutting edge surface of the workpiece, and the vertical The wire is characterized in that the straight wire and the arc-shaped wire and the workpiece are relatively moved while being discharged while the workpiece is being processed, thereby simultaneously processing the cutting edge side surface and the R portion in contact with the workpiece. This can also be achieved by an electric discharge machining method.

[0008]

In the wire electric discharge machining method according to the present invention, the wire and the workpiece are subjected to electric discharge machining in a non-contact state while being immersed in water or oil, and the circumferential end of the rotating guide or the circumference of the fixed guide. Since electric discharge machining is performed using the wire supported by the end, an R portion having the same shape and dimensions as the circumferential end can be machined. By keeping the vertical straight wire perpendicular to the cutting edge of the workpiece and moving it relative to the workpiece while discharging between the vertical straight wire and arcuate wire, the vertical straight wire In addition, the cutting edge side surface corresponding to the locus of the arc-shaped wire and the R portion in contact with the cutting edge side surface can be simultaneously processed into the workpiece.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A wire electric discharge machining method according to an embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

Embodiment 1 FIG. 1 is a schematic diagram of a wire electric discharge machining apparatus used in a wire electric discharge machining method according to a first embodiment. FIG. 2 and FIG.
2 is an enlarged view of a portion A in FIG. 1, FIG. 2 is a front view thereof, and FIG. 3 is a side view thereof.

A wire 2 is stretched between the upper wire guide 1 and a lower wire guide (not shown),
At the intermediate position between the upper and lower wire guides, wire 2 is placed on one side (left side in the figure)
A disk-shaped rotary guide 3 is provided to support the rotary guide 3 from above.
The thickness of the circumferential end 31 of the rotating guide 3 is substantially equal to the diameter of the wire 2. In order to guide the wire 2 stably, a groove having a semicircular cross section is provided at a circumferential end portion 31 of the rotation guide 3 and is designed to fit with the wire. The rotation guide 3 is pivotally supported at its center 32 by the support member 5 and can rotate freely around the center 32.
The thickness increases from the circumferential end 31 toward the center 32, and the cross-sectional shape is V-shaped. The taper angle θ near the circumferential end is 15 to 45 °. The curvature of the circumferential end of the rotary guide is substantially equal to the curvature of the R portion of the scraping punch tool to be obtained by machining. Therefore, it is necessary to prepare rotation guides having various curvatures according to the design dimensions of the scraping punch tool, and to replace and use them.

Next, an electric discharge machining method using the above-described wire electric discharge machine will be described. The lower portion or the main body of the workpiece 6 is simply held and fixed by holding it with the clamp 7. As the material of the workpiece 6, an electrically conductive material such as bearing steel, cemented carbide, or electrically conductive ceramic can be used. It should be particularly noted that hard metals that are hard to wear can also be processed by the method of the present invention. It is desirable that the clamp be installed on an automatic indexing table that can be finely moved and rotated in XYZ. Then, the workpiece is immersed in water or oil. In this way, a workpiece to be processed is set. In the illustrated embodiment, the clamp is located at the bottom. However, the clamp can be changed so that the upper wire guide portion is located at the bottom and the clamp is located upside down.

The position of the rotary guide is finely adjusted by moving the position of the rotary guide left and right in FIG. 1 so that the wire stretched between the upper wire guide portion 1 and the rotary guide is vertical. Similarly, the position of the rotation guide is moved up and down in FIG. 1 so as to be finely adjusted so that the wire stretched between the lower wire guide portion and the rotation guide is horizontal. Next, in order to obtain the processing dimensions of the workpiece 6, X
The workpiece 6 is moved up, down, left, and right in FIG. Since the radius of curvature of the R portion is determined by the radius of the rotary guide, it is exchanged in advance with a rotary guide having design dimensions. On the other hand, in the case where the intermediate machining is repeatedly performed in several steps until the final machining dimension is obtained, in order to obtain the machining dimensions of the intermediate machining in that time, an automatic indexing that can perform XYZ fine movement and θ rotation can be performed. Using the table, the workpiece 6 is moved up, down, left, and right for fine adjustment.

The finishing process using the wire electric discharge machining method of the first embodiment will be described in detail. FIG. 9 is an explanatory diagram of finishing processing using the wire electric discharge machining method of the first embodiment.

The shape of the workpiece 6 is constant because its cross section perpendicular to the reference plane 68 perpendicular to the cutting edge surface is formed by an arc (R portion 65) and a straight line (cutting edge side surface 61) in contact with the arc. The lower part of the workpiece 6 is held and fixed by holding it with a clamp 7. The clamp 7 is attached to an automatic indexing table 8, and the automatic indexing table 8 can linearly move in the X direction and the Y direction in the horizontal plane and can rotate the angle θ,
Furthermore, it can also move linearly in the vertical direction (Z direction). The workpiece 6 is formed with a rough finish surface having a constant cross section composed of an arc and a straight line in contact with the central reference surface 68 on one side of the center reference surface 68 by the intermediate processing. The rough-finished surface has a cutting edge side surface 61 parallel to the reference surface 68 and an R side contacting the cutting edge side surface 61.
A portion 65 and a main body 66 connected to the R portion. The cutting edge side surface 61 is surrounded by vertices 601, 611, 612, and 602, and the R portion 65 includes vertices 611, 621, and 6
22 and 612, and a straight line connecting the vertex 611 and the vertex 612 is a horizontal line, and forms a boundary between the cutting edge side surface 61 and the R portion 65.

On the other hand, the wire 2 extends vertically straight from the upper wire guide portion (not shown) to the rotary guide 31, and then the wire 2 is supported by the circumferential end of the rotary guide 31 in an arc of about 90 °. Further, the wire 2 is stretched in a horizontal straight line from the rotation guide 31 to the lower wire guide (not shown), and the wire 201 of the vertical straight portion, the wire 203 of the arc portion, and the wire 204 of the horizontal straight portion are co-planar. Deploy. The radius of the rotary guide 31 is determined by considering the depth of the groove formed on the circumferential end face of the rotary guide 31, the diameter of the wire 2, the discharge gap, and the discharge machining depth. A dimension corresponding to the radius of curvature of the portion 65 is selected.

Next, the relative position between the workpiece 6 and the wire 2 is adjusted. In the first embodiment, the position of the workpiece 6 is moved. First, after confirming that the workpiece 6 is not in contact with the wire 2, the workpiece 6 is slightly moved in the Z direction, and the height of the horizontal line connecting the apex 611 and the apex 612 of the workpiece 6 and the wire The height of the contact point 202 between the wire 201 of the vertical straight portion and the wire 203 of the circular arc portion in 2 is matched. Further, the workpiece 6
Is slightly rotated in the θ direction, and the reference surface 6 on the workpiece 6 is
8 and the wire 201 of the vertical straight part in the wire 2;
The wire 203 of the circular arc part and the wire 20 of the horizontal straight part
4 so as to be orthogonal to the plane 90. Subsequently, the workpiece 6 is slightly moved in the X direction and the Y direction,
, A straight line connecting the vertex 601 and the vertex 611 is close to the wire 201 of the vertical straight line portion of the wire 2, and an arc connecting the vertex 611 and the vertex 621 of the workpiece 6 is close to the wire 203 of the arc portion of the wire 2. To be placed. Of course, it is necessary to provide a predetermined discharge gap between the workpiece 6 and the wire 2.

Subsequently, the workpiece 6 is moved at a predetermined speed in the Y direction while generating an electric discharge between the workpiece 6 and the wire 2. This wire discharge occurs between the cutting edge side surface 61 of the workpiece 6 and the wire 201 of the vertical straight line portion of the wire 2 and at the same time, between the R portion 65 of the workpiece 6 and the wire 203 of the arc portion of the wire 2. Also occurs. Further, since the blade is moved in the Y direction at a constant speed while maintaining a constant discharge gap, the edge side surface 61 and the R portion 65 can be dug to a certain depth to form an extremely smooth surface. Further, since the workpiece 6 and the wire 2 are not in contact with each other, the workpiece 6 is not elastically deformed and the wire 2 is not worn, so that the shape and dimensions as designed are changed with time from the start of processing to the end of processing. Obtained without change. At the time of wire discharge, the wire 2 travels in the same manner as in the prior art, so as to be sent out from the upper wire guide portion, pass through the arc portion of the rotary guide, and be drawn into the lower wire guide portion.

In the first embodiment, the R portion 65 has an arc shape. However, if it is desired to form an elliptical arc, the workpiece 6 is slightly rotated in the θ direction to Wire 2 in a vertical straight line portion between reference plane 68 and wire 2
01, the plane 90 including the wire 203 of the arc portion and the wire 204 of the horizontal straight portion may be inclined.

When the machining of the straight portion and the R portion is completed for one side of the workpiece as described above, the automatic indexing table on which the clamp 7 holding the workpiece is mounted is rotated by 180 ° in a horizontal plane. After that, electric discharge machining of the opposite surface is performed in the same manner as described above. In the present invention, the workpiece and the wire are not in contact with each other due to wire electric discharge machining, and no excessive force acts on the workpiece. Therefore, it is not necessary to support and fix the workpiece to the clamp. Therefore, the preparation for switching to the reverse surface processing after the one-side processing can be performed extremely easily and in a short time. In some cases, the workpiece and the clamp may be attached to water or oil at 180 °.
It can also be rotated, eliminating the need to remove water or oil from the workpiece or clamp, and keeping the hands clean.

Embodiment 2 FIG. 4 is a schematic view of a wire electric discharge machining apparatus used in a wire electric discharge machining method according to a second embodiment. FIG. 5 and FIG.
5 is an enlarged view of a portion B in FIG. 4, FIG. 5 is a front view thereof, and FIG. 6 is a side view thereof.

A wire 2 is stretched between the upper wire guide 1 and a lower wire guide (not shown),
At the intermediate position between the upper and lower wire guides, wire 2 is placed on one side (left side in the figure)
A partially arc-shaped fixed guide 4 is provided to support the fixed guide 4. The thickness of the circumferential end 41 of the fixed guide 4 having a partially arc shape is substantially equal to the diameter of the wire 2. In order to stably guide the wire 2, a groove having a semicircular cross section is provided at the circumferential end 41 of the rotary guide 3, and the rotary guide 3 is designed to be fitted with the wire. The thickness increases from the circumferential end 41 toward the center 42, and the cross-sectional shape is V-shaped. The taper angle θ near the circumferential end is 15 ~
45 °. The curvature of the circumferential end of the rotary guide is substantially equal to the curvature of the R portion of the scraping punch tool to be obtained by machining. Therefore, it is necessary to prepare rotation guides having various curvatures according to the design dimensions of the scraping punch tool, and to replace and use them.

The electric discharge machining method using the wire electric discharge machine of the second embodiment is the same as that described in the first embodiment.

Embodiment 3 FIG. 7 is a view showing the formation of a deep groove by wire electric discharge machining in a third embodiment. The side surface 6 is attached to the cutting edge side 61 of the workpiece 6.
2. A deep groove consisting of the back surface 63 and the side surface 64 can be formed by the wire electric discharge machining of the third embodiment. That is, as shown in FIG. 7A, the center 32 of the rotary guide 3 is tilted with respect to the
Is perpendicular to the edge side 61. The wire is discharged while rotating the rotation guide 3, and gradually proceeds to the back to the back 63.
To reach. Next, wire discharge is performed while moving the rotation guide 3 to the center of the width along the deep surface 63 of the deep groove. The inclination of the rotation guide 3 is returned to make the center 32 parallel to the cutting edge side surface 61 (see FIG. 7B). Furthermore, the rotation guide 3 is inclined so that the lower left surface of the rotation guide 3 is perpendicular to the cutting edge side surface 61. Then, the rotation guide 3 is moved to the side surface 64 along the deep surface 63 of the deep groove.
The wire discharge is performed until the intersection with (see FIG. 7 (c)).

FIG. 8 is a perspective view of a scraping punch tool in which a deep groove is formed by wire electric discharge machining according to the third embodiment. A deep groove 67 is formed in the edge side surface 61 of the scraping punch tool 6. R between the main body 66 and the cutting edge side surface 61
There is a part 65. The width is the cutting edge side surface 61, the R part 65, the main body part 6.
6 are the same, and are substantially symmetrical with respect to the plane of symmetry in the width direction. The scraping punch tool 6 is vertically fixed on an automatic indexing table 8 capable of XYZ fine movement and rotation by a clamp 7.

Embodiment 4 FIG. 10 is an explanatory view showing a wire electric discharge machining method according to a fourth embodiment, and is a plan view of a scraping punch which is a workpiece 6 as viewed from above. The upper surface 630 of the cutting edge is hatched in FIG. 10, but has a complicated shape. The main body includes left side 631, right side 632, front 633, rear 6
The plane shape surrounded by 34 is a rectangle.
The blade side surface (not shown) is formed perpendicular to the upper surface 630, and an R portion is provided between the lower end of the blade surface and the main body. While moving the wire from the surface of the left side surface 631 to the inside like a dashed line, the wire discharges and digs and the wire 25
8 has been reached. In principle, if the plane 90 including the vertical straight line portion, the arc portion and the horizontal straight line portion of the wire is kept perpendicular to the cutting edge side surface, a smooth cutting edge side surface is obtained. However, when it has a sharp corner like a groove dug from the right side,
The planes 91 and 92 are inclined with respect to the cutting edge surface so that the side surface 33 of the rotation guide 3 does not contact the cutting edge side surface.

[0027]

(1) The wire electric discharge machining method according to the present invention is a non-contact machining method, and no excessive force acts on a workpiece. Therefore, it is sufficient to hold the workpiece only by clamping one end thereof, and the work is simple, can be performed in a short time, and has an effect that skill is not required.

(2) In the wire electric discharge machining method according to the present invention, as described in (1) above, the work piece is held only by clamping one end thereof, and there is no need to reinforce the work piece. . Therefore, the preparation for switching to the reverse surface processing after the one-side processing is completed simply requires rotating the automatic indexing table on which the clamps are mounted by 180 ° in the horizontal plane, improving the work efficiency and mounting the workpiece. The effect that an error hardly occurs is obtained.

(3) The wire electric discharge machining method according to the present invention is a non-contact machining method, and no excessive force acts on the workpiece. For this reason, since the workpiece is not deformed by the force, an effect that the processing accuracy is high without skill is obtained.

(4) The wire electric discharge machining method according to the present invention is a non-contact machining method, and no force acts on the machining tool. Therefore, unlike the conventional grinding method, the processing tool is not deformed or worn by the force, so that there is an effect that the processing accuracy is not deteriorated even if the processing is performed for a long time.

(5) In the wire electric discharge machining method according to the present invention, machining is performed in a state of being immersed in water or oil. Therefore, the workpiece is sufficiently cooled, the deformation of the workpiece due to heat can be suppressed as much as possible, and there is an effect that high processing accuracy can be obtained.

(6) In the wire electric discharge machining method according to the present invention, the thickness of the circumferential end portion of the guide is equal to the diameter of the wire, the thickness increases toward the center, and the taper angle is 15 to 45. °, a fine deep groove can be formed on the side surface of the cutting edge of the punching tool.

[Brief description of the drawings]

FIG. 1 is a schematic view of a wire electric discharge machining apparatus used in a wire electric discharge machining method according to a first embodiment.

FIG. 2 is an enlarged front view of a portion A in FIG.

FIG. 3 is an enlarged side view of a portion A in FIG. 1;

FIG. 4 is a schematic diagram of a wire electric discharge machining apparatus used in a wire electric discharge machining method according to a second embodiment.

FIG. 5 is an enlarged front view of a portion B in FIG. 4;

FIG. 6 is an enlarged side view of a portion A in FIG. 4;

FIG. 7 is a view showing formation of a deep groove by wire electric discharge machining of a third embodiment.

FIG. 8 is a perspective view of a scraping punch tool having a deep groove formed by wire electric discharge machining according to a third embodiment.

FIG. 9 is an explanatory diagram of finishing processing using the wire electric discharge machining method of the first embodiment.

FIG. 10 is an explanatory view showing a wire electric discharge machining method according to a fourth embodiment, and is a plan view of a scraping punch, which is a workpiece, as viewed from above.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Upper wire guide part 2 Wire 201 Wire of vertical straight part 202 Contact 203 Wire of arc part 204 Wire of horizontal straight part 231 Wire 232 Wire 233 Wire 234 Wire 235 Wire 236 Wire 237 Wire 238 Wire 239 Wire 240 Wire 250 Wire 251 Wire 252 wire 253 wire 254 wire 255 wire 256 wire 257 wire 258 wire 3 rotation guide 31 circumferential end 32 center 33 side 4 partly arc-shaped fixed guide 41 circumferential end 42 center 5 support member 6 workpiece 61 cutting edge Side surface 62 Side surface 63 Back surface 64 Side surface 65 R portion 66 Main body portion 67 Deep groove 68 Reference surface 601 Vertex 602 Vertex 611 Vertex 612 Vertex 621 Point 622 apex 630 blade upper surface 631 left side surface 632 right side surface 633 front 634 rear 7 clamps 8 of the automatic indexing table 90 plane 91 plane 92 plane

Claims (3)

(57) [Claims] 1. A disk-shaped rotary guide for supporting a wire from one side at an intermediate position between an upper wire guide and a lower wire guide, wherein a thickness of a circumferential end of the rotary guide is equal to a wire diameter. Using a rotating guide whose thickness increases toward the center and a taper angle of 15 to 45 °, a wire is stretched vertically straight from the upper wire guide portion to the rotating guide,
Subsequently, the wire is supported in an arc shape by the circumferential end of the rotary guide, and further, the wire is stretched in a horizontal straight line from the rotary guide to the lower wire guide, and the vertical linear wire and the arc shape are connected. The wire and the horizontal straight wire are arranged in the same plane, and the wire is pulled out from the upper wire guide portion, travels along the circumferential end of the rotary guide, and is drawn into the lower wire guide. By keeping the vertical linear wire perpendicular to the cutting edge of the workpiece, the vertical linear wire and the arcuate wire and the workpiece are relatively moved while being discharged while being discharged. A wire electric discharge machining method comprising simultaneously machining a side surface of a cutting edge and an R portion in contact with the workpiece. 2. A disk-shaped fixed guide for supporting a wire from one side at an intermediate position between an upper wire guide and a lower wire guide, wherein the thickness of the circumferential end of the fixed guide is equal to the wire diameter. Using a fixed guide whose thickness increases toward the center and whose taper angle is 15 to 45 °, a wire is stretched vertically straight from the upper wire guide portion to the fixed guide,
Subsequently, the wire is supported in an arc shape by a circumferential end portion of the fixed guide, and further, the wire is stretched in a horizontal straight line from the fixed guide to the lower wire guide, and the vertical linear wire and the arc shape are connected. The wire and the horizontal straight wire are arranged in the same plane, and the wire is pulled out from the upper wire guide portion, travels along the circumferential end of the fixed guide, and is drawn into the lower wire guide. By keeping the vertical linear wire perpendicular to the cutting edge of the workpiece, the vertical linear wire and the arcuate wire and the workpiece are relatively moved while being discharged while being discharged. A wire electric discharge machining method comprising simultaneously machining a side surface of a cutting edge and an R portion in contact with the workpiece. 3. A partially arcuate fixed guide for supporting a wire from one side at an intermediate position between an upper wire guide and a lower wire guide, wherein the thickness of the end of the arcuate portion of the fixed guide is reduced. It is equivalent to the wire diameter, the thickness increases toward the center, and the taper angle is 1
Using a fixed guide that is 5 to 45 °, the wire is stretched vertically straight from the upper wire guide portion to the fixed guide, and then the wire is supported in an arc shape by the circumferential end of the fixed guide. Further, the wire is stretched in a horizontal straight line from the fixed guide to the lower wire guide, and the vertical linear wire, the arc-shaped wire, and the horizontal linear wire are arranged in the same plane, Is pulled out from the upper wire guide portion, and is passed along the circumferential end of the fixed guide, and is run so as to be drawn into the lower wire guide, while keeping the vertical linear wire perpendicular to the cutting edge surface of the workpiece. The workpiece is discharged by relatively moving the vertical linear wire and the arc-shaped wire and the workpiece while discharging. Wire electrical discharge machining method characterized by machining the edge sides and R portion in contact with it at the same time at the object.