WO2000006331A1

WO2000006331A1 - Press die and method for treating surface of press die

Info

Publication number: WO2000006331A1
Application number: PCT/JP1999/001700
Authority: WO
Inventors: Seiji Satou; Akihiro Goto
Original assignee: Mitsubishi Denki Kabushiki Kaisha
Priority date: 1998-07-31
Filing date: 1999-03-31
Publication date: 2000-02-10
Also published as: JP2000042838A

Abstract

A die having a good abrasion resistance even at a cutting side face (104) including a die hole inner circumferential face and a long life and not inviting an increase in deform of a press-formed article due to the wear of the cutting side face after a long use by forming, on a cutting side face (104), a modified layer (108) of an electrode wear fused substance of a discharge electrode (15) produced by electric discharge energy of submerged electric discharge machining or of reaction products of the electrode wear fused substance.

Description

Description Press working die and surface treatment method of press working die

The present invention relates to a stamping die and a surface treatment method of the stamping die, and particularly to a stamping die used for shearing such as punching and punching, and a surface treatment method of such a stamping die. It is about. Background art

Pressing dies used for shearing such as drilling and punching require high wear resistance, especially at the cutting edge, in order to obtain the required durability (die life).

Conventionally, press working dies are generally made of high-hardness metal materials such as carbon tool steel and alloy tool steel, and their heat resistance has been improved by heat treatment.

Extending the life of a die in press working is one of the most important issues. ^ With the increasing precision and diversification of press working, the demands on the life of punching dies etc. are becoming more and more severe. It has become increasingly difficult to ensure the required durability in surface treatments.

In response to this, the surface layer on the upper surface of the material of the punch press die such as a die is melted by high energy such as a laser, and the hardened material having good wear resistance such as metal carbide The surface-treated string portion impregnated with the hard component by adding the components is formed into a ring shape, and then a die hole is formed along the surface-treated string portion by wire electric discharge machining. No. 84 discloses this. In the case of stamping dies, considering the life of the mold and the quality of the stamped product, not only the cutting edge but also the cutting edge (cutting edge) The peripheral surface) is also required to have excellent wear resistance.

However, in the prior art as described above, a hard component-impregnated portion is locally provided at the cutting edge 緣 portion. As a result, the surface treatment of the cutting edge side surface that is continuous with the cutting edge edge cannot be performed, that is, relatively wide surface treatment cannot be performed, and the wear resistance of the cutting edge side surface is improved. I can't let it. For this reason, there is a limit to the improvement of the service life of the press-working die, and it is inevitable that the amount of shear in the sheared portion of the press-worked product increases due to wear of the cutting edge side surface due to repeated use.

The present invention has been made in order to solve the above-mentioned problems, and has a good abrasion resistance on a cutting edge side surface constituted by an inner peripheral surface of a die hole and the like, and has an excellent die life. The object of the present invention is to provide a press-working die and a surface treatment method of a press-working die which do not cause an increase in the droop amount of a press-processed product due to wear of the cutting edge side even when used for a long time. I have. Disclosure of the invention

According to the press-working die according to the present invention, since the reformed layer is formed on the side surface of the cutting edge by a discharge surface treatment by a gap discharge in the liquid, the molten material or the reactant thereof is used to greatly improve the life of the die. To improve.

Further, according to the press-working die according to the present invention, the wear resistance of the cutting edge side surface is improved because the cutting edge side surface is covered with the hard coating generated by the discharge surface treatment by the gap discharge in liquid. The mold life is greatly improved.

Further, according to the press working mold according to the present invention, WC the cutting edge side, T i Z r C. VC, carbides such as _{T a C, T i B 2} , Z r B 2 , etc. borides, T i Since a modified layer is formed by a single or combination of nitrides such as N and TrN, the wear resistance of the cutting edge side is improved, and the mold life is greatly improved.

Further, according to the press working die according to the present invention, since the modified layer is formed on the inner surface of the die hole that is continuous with the cutting edge formed by the opening edge of the die hole of the die, the die life of the die is reduced. Is greatly improved.

Further, according to the surface treatment method of the press working die according to the present invention, the electrode depleted molten material is formed on the side surface of the cutting edge of the press working die by the discharge surface treatment by the gap discharge in the liquid. Alternatively, since the reformed layer is formed in a planar shape by the reaction product thereof, the life of the stamping die can be greatly improved.

In addition, according to the surface treatment method for a press-working die according to the present invention, the reaction between the electrode material and the HC of the electric discharge machining oil causes the cutting edge side surface to be hardened such as TiC, ZrC, VC, TaC or the like. Since it is coated with a porous coating, the abrasion resistance of the cutting edge side is improved, and the life of the mold can be greatly improved.

Further, according to the surface treatment method for a press die according to the present invention, a simple shape electrode is used, the gap between the cutting edge side surface and the simple shape electrode is kept at a predetermined value, and the simple shape electrode and the processing target are pressed. Since the reforming layer is formed on the side of the cutting edge by displacing the cutting die relative to the side of the cutting edge determined by the press processing shape, there is no need to prepare an electrode for each pressing die shape. The use of shaped electrodes makes it possible to significantly improve the service life of micro-shaped press dies typified by IC lead frames. Further, according to the surface treatment method of the press die according to the present invention, the machining used in the wire electric discharge machining for forming the die while maintaining the gap between the side surface of the cutting edge of the die die and the simple shape electrode at a predetermined value. Using a program to relatively displace the simple shape electrode and the die to be processed and forming a modified layer on the side surface of the cutting edge, the press can be performed without the need for a special processing program for surface treatment. The surface treatment of the cutting blade side surface of the mold can be performed. Further, according to the surface treatment method for a press-working die according to the present invention, a simple shape electrode is used, and the gap between the cutting edge and the simple shape electrode is controlled by a gap. The gap between the shape electrode and the shape electrode is maintained at a predetermined value, and the simple shape electrode and the pressing die to be processed are displaced relative to each other according to the shape of the cutting edge side surface determined by the pressed shape, and the modified layer is formed on the side surface of the cutting edge. Forming a hard coating on the side surface of the cutting edge makes it possible to significantly improve the life of the press die and significantly reduce the time required for surface treatment.

Further, according to the surface treatment method of the press die according to the present invention, the wire electrode is used and the gap between the cutting edge side surface and the wire electrode is maintained at a predetermined value, and the wire electrode and the target to be pressed are processed. Relative to the mold according to the cutting edge side shape determined by the pressed shape Because it displaces and forms a modified layer on the side surface of the cutting edge, there is no need to prepare an electrode for each press die shape, greatly improving the die life of a fine-shaped press die represented by an IC lead frame. It becomes possible. In addition, surface treatment can be performed without being conscious of electrode wear, and a modified layer can be formed on the side surface of the cutting blade with high precision. Further, according to the surface treatment method of the press die according to the present invention, the machining program used in the wire electric discharge machining of the die while maintaining the gap between the cutting edge side surface of the die die and the wire electrode at a predetermined value is provided. The simple shape electrode and the die to be processed are relatively displaced to form a modified layer on the side surface of the cutting edge, so a special processing program for surface treatment is not required. Surface treatment of the cutting edge side surface can be performed. Further, according to the surface treatment method for a press-working die according to the present invention, the same wire discharging machine is used to perform mold processing using the wire electrode for wire electric discharge machining, and thereafter, the wire for surface treatment is used. Since the modified layer is formed on the side surface of the cutting edge using electrodes, it is possible to form a hard film on the side surface of the cutting edge by setting the same processing for the shape processing and surface treatment of the cutting edge. In addition to greatly improving the life of the surface, the time required for surface treatment can be significantly reduced.

According to the surface treatment method for a press die according to the present invention, a modified layer is formed on the upper surface of a die material by a discharge surface treatment before the die hole is formed, and after the die hole is formed, Since the modified layer is formed on the side surface of the cutting edge, the life of the die can be further improved. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a configuration diagram showing Embodiment 1 of a surface treatment apparatus used for carrying out a surface treatment method for a press working die according to the present invention, and FIG. 2 is a press working die according to the present invention. FIG. 3 is a perspective view showing a state in which a modified layer is formed on a cutting blade side surface of a die using a simple shape electrode in the surface treatment method of FIG. 3, and FIG. FIG. 4 is an explanatory view showing the correction procedure of the movement path of the simple shape electrode in the processing method, and FIG. 4 is a graph showing the correction value characteristics of the movement path of the simple shape electrode. FIG. 5 is a cross-sectional view showing a punch die having a modified layer formed on a side surface of a cutting edge by the surface treatment method for a press die according to the present invention, and FIG. 6 is a press die according to the present invention. FIG. 7 is a configuration diagram illustrating a second embodiment of a surface treatment apparatus used for performing a surface treatment method of a mold. FIG. 7 is an explanatory diagram illustrating a moving path of a simple shape electrode by inter-pole servo. FIG. 8 is a configuration diagram showing Embodiment 3 of a surface treatment apparatus used for performing the surface treatment method for a press working die according to the present invention, and FIG. 9 is a press working metal according to the present invention. FIG. 10 is a perspective view showing a state in which a modified layer is formed on a side surface of a cutting edge of a die using a wire electrode in the surface treatment method of the die. FIG. Embodiment of the surface treatment device used for performing the mold surface treatment method FIG. 11 is an explanatory view showing a surface treatment method and a mold processing procedure of a stamping die according to the present invention, and FIG. (A) to (c) are explanatory views showing a surface treatment method for a press-working die and a procedure of the die working according to the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

With reference to the accompanying drawings, embodiments of a press processing die and a press processing die surface treatment method according to the present invention will be described in detail below.

FIG. 1 shows a first embodiment of a surface treatment apparatus used for carrying out a surface treatment method for a press die according to the present invention.

This surface treatment device is a kind of electric discharge machine, and has a superposed structure of an X-axis table 1 movable in the horizontal X-axis direction and a Y-axis table 3 movable in the horizontal Y-axis direction. A work table 5 is provided, and a processing tank 7 is fixed on the work table 5.

A processing material mounting table 9 is provided in the processing tank 7, and a pressing die as a processing material, in the illustrated example, a die mold 100 is mounted and fixed on the processing material mounting table 9. You. A processing liquid is supplied into the processing tank 7 from a processing liquid supply device (not shown), and a die 100 on the workpiece mounting table 9 is immersed in the processing liquid. An electrode support bed 11 movable in the vertical Z-axis direction is provided above the processing tank 7, and a rotary electrode support device 13 is provided below the electrode support bed 11. It has been. The electrode support device 13 exchangeably supports the simple shape electrode 15 by a rod and can rotate the simple shape electrode 15 around the electrode axis. The simple shape electrode 15 is in the shape of a round bar, and its outer diameter is selected according to the size of the material to be processed. When the material to be processed is a die 100, the size may be set so that the simple shape electrode 15 is included in the die hole 102.

The X-axis table 1, Y-axis table 3, and electrode support bed 11 are positioned and driven by X-axis servo motor 17, Y-axis servo motor 19, and Z-axis servo motor 21, respectively. The X-axis servo motor 17, Y-axis servo motor 19, and Z-axis servo motor 21 are position-controlled by the axis commands output by the locus movement controller 25 of the numerical controller 23. You.

The trajectory movement control unit 25 of the numerical controller 23 receives the trajectory movement data (electrode path information) from the electrode movement trajectory generation CAM device 27, and based on the trajectory movement data, the X-axis, Y-axis, and Z-axis. Generate a position index for each axis.

When the surface treatment method for a press-working die according to the present invention is performed using the surface treatment apparatus having the above-described configuration, the die mosquito L 102 is processed by grinding or wire electric discharge machining. For the shape of the cutting edge 106 of the mold, the die 100 already formed is set on the work table 9 and the processing liquid is stored in the processing tank 7 to process the work table. The die 100 on 9 is immersed in the working fluid.

In the machining fluid in the machining tank 7, the cutting edge side surface 104 provided by the inner peripheral surface of the die hole 100 of the die 100 and the simple shape electrode 15 are fixed to a predetermined discharge gap g ( (See Fig. 3). A pulse voltage is applied between the cutting edge side surface 104 and the simple-shaped electrode 15 with the pulsed discharge generated. As a result, the electrode-consumed molten material generated by the discharge energy or a reaction product of the electrode-consumed molten material and the machining fluid component adheres and deposits on the cutting edge side surface 104 connected to the cutting edge 106 formed by the opening edge of the die hole 102. Then, the modified layer 108 (see Fig. 2) made of electrode-consumed molten material or its reactant is compared to the cutting edge side surface 104. It is formed in a wide area.

The modified layer 108 is a hard coating having excellent wear resistance. The material of the modified layer 108 is a carbide such as WC, TiC :, ZrC, VC, TaC, etc. _{, T i B 2, Z r} B boride such as _2, T i N, single nitrides such as T r N, or also be mentioned that by a combination thereof.

In addition, as the simple shape electrode 15, a powder of a hard metal such as Ti, Zr, V, Ta, or a green compact electrode obtained by compression-molding a powder of a hydride thereof, or a metal of these metals Using electrodes and using EDM oil containing HC as the machining fluid, metal carbides such as TiC, ZrC, VC, and TaC are formed by the reaction between the electrode material and HC in the EDM oil. The hard coating can be efficiently and satisfactorily formed on the cutting edge side surface 104.

The method for forming the modified layer 108 by pulse discharge as described above conforms to a method called a discharge surface treatment method using gap discharge in liquid. This discharge surface treatment method is disclosed in It is shown in Japanese Patent Application Laid-Open No. 826266, Japanese Patent Application Laid-Open No. H8-2587841, Japanese Patent Application Laid-Open No. 9-198028, and Japanese Patent Application Laid-Open No. 9-1929337. .

The formation of the reformed layer 108 is performed uniformly over the entire circumference of the cutting edge side surface 104. To this end, the gap g between the cutting edge side surface 104 and the simple shape electrode 15 is maintained at a predetermined value, and the fine simple shape electrode 15 and the die mold 100 which is a pressing die to be processed. It is necessary to make a relative displacement according to the cutting edge side shape determined by the press working shape (die hole plane shape), and this relative displacement causes the modified layer 108 to cover the entire periphery of the cutting edge side 104. Can be formed.

The relative displacement between the simple shape electrode 15 and the mold 100 following the cutting edge side shape can be performed by moving the X-axis table 1 in the X-axis direction and the Y-axis table 3 in the Y-axis direction. .

The trajectory movement control unit 25 provided inside the numerical controller 23 is a simple shape electrode 15 for surface treatment based on the electrode movement path information created by the electrode trajectory generation CAM 27 in advance. Relative movement control of the X axis table 1 and Y axis table The drive control of the bull 3 is performed so that the locus movement of the simple shape electrode 15 traces the cutting edge side surface 104. Here, the simple shape electrode 15 is controlled in the Z-axis direction (depth direction) to have a constant height in accordance with the position of the cutting blade 106 in the Z-axis direction.

In the above-described embodiment, the electrode moving program of the electric discharge surface treatment processing is such that the die hole 100 of the force die 100 created by using the dedicated CAM is formed by wire electric discharge. In this case, the simple shape electrode 15 and the die 100 are relatively displaced using the machining program used in wire electric discharge machining of the die hole, and the cutting edge side surface 102 is modified. Layer 108 can also be formed.

FIG. 2 shows a state in which a discharge surface treatment is performed on a side surface of a cutting edge of a die 100 as a material to be processed. The formation of the modified layer 108 on the cutting edge side surface 104 of the die 100 is performed by using the side surface of the simple shape electrode 15 as shown in FIG.

In this discharge surface treatment, the electrode material is consumed with the progress of the discharge surface treatment, so that the side surface of the simple shaped electrode 15 is worn and thinned, and the discharge state is not stable. Therefore, in order to stabilize the discharge state, the simple electrode 15 is rotated around the electrode axis by using the rotary electrode support device 13.

When the discharge surface treatment is performed by tracing the cutting edge shape using the side surface of the simple shape electrode 15, the simple shape electrode 15 is consumed as the discharge surface treatment progresses, and the electrode diameter gradually increases. Therefore, as shown in FIG. 3, it is necessary to correct the electrode moving path P in a direction in which the electrode moving path P approaches the material to be processed, according to the moving amount (machining distance) of the simple shape electrode 15.

If the machining feed amount and the electrode rotation speed are both constant, the amount of electrode consumption with respect to the machining distance is constant if the machining feed amount and the electrode rotation speed are constant. Thus, a linear proportional relationship is obtained with a proportional constant. Therefore, it is sufficient to perform linear tool diameter correction with respect to the machining distance in the normal direction of the cutting edge shape with the correction amount c g.

As described above, the simple shape electrode 15 is moved so as to trace the side surface of the cutting edge, The surface of the die 100 is subjected to a discharge surface treatment while maintaining a proper gap (discharge gap) g while giving a correction value cg for the electrode consumption in the normal direction of the cutting edge shape. The modified layer 108 made of a hard coating can be formed in a plane over the entire region of No. 4.

Using the method described above, a hard coating was formed on the side of the cutting edge of the punching die by electric discharge surface treatment, and a press punching test was performed. The drooping amount of the pressed product at the time of 100,000 shots was 1 Z 2 or less, and the longevity of the die was realized.

If electrodes with a fine shape of about 0.1 mm 15 are used as electrodes for discharge surface treatment, hard coating can be applied to the side of the cutting edge of a micro-shaped press die such as an IC lead frame. The mold life can be greatly improved.

The above description describes a method of forming a hard coating on the cutting edge side surface of the die by electric discharge surface treatment. As shown in FIG. 5, the cutting edge side surface of the punch die 200 Similarly, the modified layer 204 can be formed by the discharge surface treatment using the gap discharge in the liquid.

In addition, by performing discharge surface treatment on the upper surface of the cutting blade, forming a hard coating on the upper surface of the cutting blade, and improving the wear resistance of this portion, the mold life can be further improved. Needless to say.

FIG. 6 shows a second embodiment of a surface treatment apparatus used for carrying out the surface treatment method for a press die according to the present invention. In FIG. 6, portions corresponding to FIG. 1 are denoted by the same reference numerals as those in FIG. 1, and description thereof will be omitted.

In this embodiment, in order to perform inter-electrode servo control, a U-axis moving means 31 for moving the simple shape electrode 15 in the horizontal U-axis direction on the electrode support portion and a simple shape electrode 15 V-axis moving means 33 for moving in the V-axis direction is provided. The U-axis moving means 31 and the V-axis moving means 33 are driven by the U-axis servomotor 35 and the V-axis servomotor 37, respectively. Evening 3 7 The position is controlled by each axis command output from the gap servo movement controller 39 of the numerical controller 23.

The gap servo movement control unit 39 inputs the average voltage between the simple shape electrode 15 and the material to be processed detected by the average voltage detecting means 41, and based on the average voltage (detection result), The U-axis position command and V-axis position command are output so that the distance g between the surface to be processed (cutting side surface 104) and the simple shape electrode 15 is kept constant.

In this embodiment, as shown in FIG. 7, the shape of the simple shape electrode 15 is adjusted so that the distance between the cutting edge side surface 104 and the simple shape electrode 15 becomes constant with respect to electrode wear. Performs inter-pole servo by U-axis control and V-axis control according to the decrease in electrode diameter. As a method of inter-pole servo, the average voltage of the material to be processed and the simple shape electrode 15 is detected using the average voltage detecting means 41, and the average voltage is generally kept constant in the electric discharge machine. An average voltage constant servo for movement control is taken.

FIG. 7 shows the direction of the electrode movement path and the gap between the electrodes. As for the direction of the gap-to-pole servo, a side surface relief is taken in the normal direction to the electrode movement path.

As described above, the discharge surface treatment is performed so as to trace the cutting edge shape while removing the gap between the cutting edge side surface 104 to be processed and the simple shape electrode 15 between the poles. By forming a hard coating on the side surface 104 of the cutting edge, it is possible to significantly improve the life of the mold as in the first embodiment, and at the same time remove the gap between the poles. Since the discharge surface treatment is performed, the effect that the machining time can be reduced can be obtained.

FIG. 8 shows a third embodiment of a surface treatment apparatus used for carrying out the surface treatment method for a press die according to the present invention. In FIG. 8, portions corresponding to FIG. 1 are denoted by the same reference numerals as those in FIG. 1, and the description thereof is omitted.

This surface treatment device is a type of wire electric discharge machine, in which an X-axis table 51 movable in the horizontal X-axis direction and a Y-axis table 5.3 movable in the horizontal Y-axis direction are overlapped. It has a work table 55 with a matching structure. A work table 57 is provided on the worktable '55, and the work table 57 is provided on the work table 57. A press die as a base material, in the illustrated example, a die die 100 is mounted and fixed.

X-axis table 5 KY-axis table 53 are driven by X-axis servo motor 59 and Y-axis servo motor 61, respectively, and X-axis servo motor 59 and Y-axis servo motor 61 are numerically controlled. The position is controlled by each axis control command output by the trajectory movement control unit 25 of the device 23.

Wire electrode guides 63, 65 are provided above and below the workpiece mounting table 57, respectively, and the wire electrode 69 for surface treatment unreeled from the wire bobbin 67 is provided with the wire electrode guide 63. It is designed to run vertically between 65. The wire electrode 69 is positioned between the wire electrode guides 63 and 65 in the die hole 102 of the die 100 on the workpiece mounting table 57 with respect to the cutting edge side surface 104. Run up and down while maintaining the prescribed discharge gap.

A machining fluid is sprayed from a machining fluid nozzle 71 to a discharge gap between the wire electrode 69 and the cutting edge side surface 104.

When the surface treatment method for a press-working die according to the present invention is performed using the surface treatment apparatus having the above-described configuration, the die hole 102 is processed by grinding or wire electric discharge machining. The die 100 having the shape of the cutting edge 106 already formed is set on the workpiece mounting table 57, and the processing liquid is sprayed from the processing liquid nozzle 71.

In this state, the cutting edge side face 104 provided by the inner peripheral surface of the die hole 100 of the die 100 and the wire electrode 69 face each other with a predetermined discharge gap, and the cutting edge side face 10 0 A pulse voltage is applied between the wire 4 and the wire electrode 69 to generate a pulse discharge in the machining fluid ejected from the machining fluid nozzle 71. As a result, the electrode consumable molten material generated by the discharge energy or the reaction product of the electrode fluid and the machining fluid component adheres and accumulates on the cutting edge side surface 104 connected to the cutting edge 106 forming the opening edge of the die hole. As shown in FIG. 9, a reformed layer 108 made of the electrode consumable molten material or a reaction product thereof is formed on the cutting edge side surface 104 in a relatively wide area.

Wire electrode 69 made of hard metal such as Ti, Zr, V, Ta, etc. Using an EDM oil containing HC as the machining fluid, and by reacting the electrode material with HC in the EDM oil, the metal carbides such as TiC, ZrC, VC :, and TaC The hard coating can be efficiently and satisfactorily formed on the cutting edge side surface 104.

The formation of the reformed layer 108 is performed uniformly over the entire circumference of the cutting edge side surface 104. To this end, the gap between the cutting edge side surface 104 and the wire electrode 69 is maintained at a predetermined value, and the wire electrode 69 and the die die 100 to be processed are pressed. It is necessary to make relative displacement according to the cutting edge side shape determined by the press processing shape (die hole plane shape), and the relative displacement causes the modified layer 108 to cover a relatively wide area all around the cutting edge side surface 104. Can be formed.

The relative displacement between the wire electrode 69 and the mold 100 following the shape of the cutting edge side surface is performed by moving the X-axis table 51 in the X-axis direction and the Y-axis table 53 in the Y-axis direction. Can be.

The trajectory movement control unit 25 provided inside the numerical control device 23 is based on the electrode movement path information created in advance by the electrode trajectory generation CAM 27 as in the first embodiment. The lateral movement of the wire electrode 69 for surface treatment, ie,

The drive control of the X-axis table 51 and the Y-axis table 53 is performed so that the locus movement of the wire electrode 69 traces the cutting edge side surface 104.

In the above-described embodiment, the electrode moving program for the electric discharge surface treatment is a special C

Although it is created using AM, if the die hole 102 of the die 100 is formed by wire electric discharge, the machining program used for wire electric discharge machining of the die hole is used. The wire electrode 69 and the die 100 are relatively displaced using

A modified layer 108 can be formed on 104.

The formation of the modified layer 108 on the cutting edge side surface 104 of the die 100 is performed using the wire electrode 69 as shown in FIG. Power consumption \ New wire electrode 69 for surface treatment is always supplied from wire bobbin 67, so discharge surface treatment can be performed without being aware of the wear of wire electrode 69

. Therefore, as the movement path of the wire electrode 69, the electrode movement of wire electric discharge machining It may be as simple as a path.

As described above, by performing the surface treatment by moving the wire electrode 69 so as to trace the side surface of the cutting edge, the modified layer of the hard coating is formed on the side surface of the cutting edge in a relatively wide area. Can be formed.

As a result, a press-working die similar to that in the first embodiment can be obtained, and the life of the die can be prolonged.

FIG. 10 shows a fourth embodiment of a surface treatment apparatus used for carrying out the surface treatment method for a press die according to the present invention. In FIG. 10, portions corresponding to those in FIG. 8 are denoted by the same reference numerals as those in FIG. 8, and description thereof will be omitted.

In this embodiment, in order to perform die machining such as die hole formation and electric discharge surface treatment in one wire electric discharge machine, wire electric discharge machining is performed separately from wire electrode 69 for surface treatment. A wire electrode 73 for surface treatment and a wire electrode 73 for wire electric discharge machining are switched and used by a wire electrode switching means 75. .

The wire electrode 69 for surface treatment is paid out from the wire bobbin 67, guided by the wire electrode guide 63, reaches the wire electrode switching means 75, and the wire electrode switching means 75 and the wire electrode guide 6 are provided. Run vertically between 5.

The wire electrode 73 for wire electric discharge machining is drawn out from the wire bobbin 77, guided by the wire electrode guide section 79 to the wire electrode switching means 75, and the wire electrode switching means 75 and the wire electrode guide section. Drive vertically between 6 and 5.

Next, the operation of this embodiment will be described. Here, a case where the material to be processed is used as a punch die is described. The machining procedure is as follows: First, as a setup operation, a wire electrode 69 for surface treatment and a wire electrode 73 for wire electric discharge machining are set. 7 Set on top.

After the above-mentioned setup work is completed, the first step is the wire electrode for wire electric discharge machining. The die hole 102 is machined by wire electric discharge machining in a state where the machining fluid is jetted from the machining fluid nozzle 71 to the discharge gap portion by using 73 to form a cutting blade 106. When the die machining (the first step) is completed, the wire electrode to be used is changed from the wire electrode for wire electric discharge machining 73 to the wire electrode for surface treatment 69 9 by the wire electrode switching means 75. In the second step, a wire electrode 69 for surface treatment was used, and a machining fluid nozzle 7 1 was attached to the discharge gap between the wire electrode 69 and the cutting edge side surface 104 as in the second embodiment. The surface of the cutting edge side 104 of the die moss L102 processed by wire electric discharge machining was sprayed with a machining fluid, and the surface of the cutting edge 104 was modified with a hard coating on the side surface 104. 0 8 (see Fig. 9).

At the time of wire electric discharge machining, which is the first step, as shown in FIG. 11 (a), the trajectory of the wire electrode 73 is moved so as to machine the cutting edge 106 on the mold material 100a. (Electrode movement path P a) needs to be controlled. The trajectory movement control unit 25 provided inside the numerical control device 23 is based on the electrode path information created in advance by the electrode trajectory generation CAM 27, and is located next to the wire electrode 73 for wire electric discharge machining. Direction relative movement control, that is, axis control of the X-axis table 51 and Y-axis table 53, so that the trajectory movement of the wire electrode 73 conforms to the processing shape of the cutting edge type It shall be done.

At the time of the surface treatment, which is the second step, as shown in FIG. 11 (b), the locus movement of the wire electrode 69 was changed to the cutting edge shape (die hole shape) of the die 100. It needs to be controlled to a solid one. In this case, the locus movement control unit 25 of the numerical controller 23 is based on the electrode path information created in advance by the electrode locus generation CAM 27 in the same manner as the normal finishing process of wire electric discharge machining. The axes of the X-axis table 51 and the Y-axis table 53 are controlled, and the trajectory of the wire electrode 69 is traced along the side surface 104 of the cutting blade.

As mentioned above, the cutting edge processing of a press die such as a die is performed by wire electric discharge machining, and after the cutting edge processing, the discharge surface treatment by gap discharge in liquid is performed on the side surface of the cutting edge into a cutting edge shape. By tracing and forming a hard coating on the cutting edge side 104, As in the first embodiment, the mold life can be greatly improved.

Further, in this case, since the cutting edge processing and the surface treatment processing of the press die can be performed in the same setup, there is an effect that the processing time is shortened and the setup work can be greatly simplified.

In this embodiment, the wire electrode 73 for wire electric discharge machining and the wire electrode 69 for surface treatment are automatically switched using the electrode switching means 75. The machining may be performed later by replacing the wire electrode manually. In this case, the trouble of replacing the wire electrode is increased, but there is a merit that the electrode switching means 75 can be omitted and the device can be provided at low cost.

As shown in FIGS. 12 (a) to 12 (c), before forming the die hole 102 of the die 100, the rod-shaped surface treatment electrode 81 is used. A modified layer 110 is formed on the upper surface of the die material 100a by electric discharge surface treatment, and after forming a die hole 102 by wire electric discharge machining, a modified layer is formed on the side surface 104 of the cutting edge. It can also be formed.

In this case, the processing steps are as follows: surface treatment (cutting blade upper surface part), wire electric discharge machining (cutting blade shape processing), and surface treatment processing (cutting blade side surface). Since the hard coating is formed on the side surface of the cutting edge by the discharge surface treatment, the life of the mold is further improved. Industrial applicability

As described above, the press die and the surface treatment method of the press die according to the present invention include a press die used for shearing such as punching and punching, and a surface of a press die of such type. Suitable for processing.

Claims

The scope of the claims

1. Discharged electrode material of the discharge electrode generated by the discharge energy due to submerged electric discharge machining on the side of the cutting edge, and the reactant of the electrode is deposited and deposited on the side of the cutting edge. A press-working die, characterized in that a pressurized layer is formed.

2. The press working die according to claim 1, wherein the modified layer is a hard coating.

3. The modified layer is WC, Ti C :, ZrC :, VC , carbides such as _{TaC, Ti B 2, Zr B} 2 , etc. borides, TiN, single nitrides such TrN or due combinations, The press-working die according to claim 1, wherein:

4. The press working according to claim 1, wherein in the die, the modified layer is formed on an inner surface of the die hole that is continuous with a cutting edge formed by an opening edge of the die hole. Mold.

5. In the working fluid, the cutting edge side of the press die and the discharge electrode are opposed to each other with a predetermined discharge gap, and a discharge is generated between the cutting edge side and the discharge electrode. The press-forming die, which specializes in depositing the generated electrode consumable molten material or its reactant on the side of the cutting edge and forming a reformed layer of the electrode consumable molten material or its reactant on the side of the cutting edge. Surface treatment method.

6. As the discharge electrode, use a powder of a hard metal such as Ti, Zr, V, or Ta, or a compact electrode formed by compressing and molding these hydride powders, or a metal electrode made of these metals Forming a reformed layer using EDM oil containing HC as the machining fluid 6. The surface treatment method for a press-working die according to claim 5, wherein:

7. The simple shape electrode is used, and the gap between the cutting edge side and the simple shape electrode is maintained at a predetermined value, and the simple shape electrode and the pressing die to be processed are set to the cutting edge side shape determined by the pressed shape. 6. The surface treatment method for a press-working die according to claim 5, wherein the modified layer is formed on a side surface of the cutting edge by relatively displacing the same.

8. The stamping die to be processed is a die formed by wire discharge machining, using a simple shape electrode and maintaining the gap between the cutting edge side and the simple shape electrode at a predetermined value. 6. A modified layer is formed on a side surface of a cutting edge by relatively displacing a simple shape electrode and a die to be processed using a machining program used in wire electric discharge machining. 4. The surface treatment method for a press-working die according to 4. above.

9. The gap between the cutting edge side and the simple shape electrode is maintained at a predetermined value by using a simple shape electrode and performing inter-electrode servo control between the cutting edge side and the fine simple shape electrode, 6. The modified layer is formed on the side surface of the cutting edge, wherein the electrode having a simple shape and the pressing die to be processed are relatively displaced in accordance with the shape of the side surface of the cutting edge determined by the pressing shape. 4. The surface treatment method for a press-working die according to 4. above.

10. Using a wire electrode, the gap between the cutting edge side and the wire electrode is kept at a predetermined value, and the wire electrode and the pressing die to be processed are shaped according to the cutting edge side shape determined by the pressing shape. 6. The surface treatment method for a press-working die according to claim 5, wherein the modified layer is formed on the side surface of the cutting edge by relative displacement.

1 1. The die to be processed is a die formed by wire electric discharge machining. The wire discharge is performed by using a wire electrode and maintaining the gap between the cutting edge side surface and the wire electrode at a predetermined value. Using the processing program used in the processing 6. The surface treatment method for a press-working die according to claim 5, wherein a modified layer is formed on a side surface of the cutting edge by relatively displacing the elephant die.

1 2. In the same wire electric discharge machine, perform die machining using wire electrodes for wire electric discharge machining, and then form a modified layer on the side surface of the cutting edge using wire electrodes for surface treatment. 6. The surface treatment method for a press-working die according to claim 5, wherein:

1 3. The die to be processed is a die, and before forming the die hole of the die, a modified layer is formed on the upper surface of the die material by discharge surface treatment, and after forming the die hole. 6. The surface treatment method for a press-working die according to claim 5, wherein a modified layer is formed on a side surface of the cutting blade.