JPH0549418B2 - - Google Patents

Description

Detailed Description of the Invention "Industrial Application Field" The present invention relates to a method for manufacturing a mold for deburring a casting in electrical discharge machining, and in particular, uses a casting prototype model as it is, and uses this prototype model in electrical discharge machining. This invention relates to an electrode for a device.

``Prior art'' Conventionally, when manufacturing a deburring mold, the dimensions are usually measured from a prototype model, the measurements are registered in a computer, and then mechanical means such as wire cutting, cutting, polishing, etc. are performed based on this registration. to form a mold piece, and assemble the divided mold pieces,
The primitive method of manufacturing the upper and lower molds by integrating them, or the electroforming method, involves applying copper plating to the outer surface of the original model material such as plaster or plastic made in the mold. There is a method of manufacturing a deburring mold through electrical discharge machining using this copper-plated original model (matrix), which is mainly used as a mold for masks and record discs. This method has the disadvantages that scratches, cracks, etc. left on the matrix cannot be regenerated, and that the work is complicated, such as when plastic is used as the matrix, pretreatment such as sensitization of the front side is required. There was a problem.

In addition, there is a method for manufacturing a tire molding mold by electrical discharge machining, as disclosed in Japanese Patent Publication No. 59-29369, etc., and the gist is that the tire molding mold has a tire molding surface and a plurality of protrusions on this surface. A manufacturing method in which a mold is machined by an electric discharge machining device, which includes: a machining head that is rotated within a plane corresponding to the rotation axis of the tire and rapidly fed in the feeding direction at a predetermined rotation angle position; An electrical discharge machining device having a rotatable head support portion that supports the head at the rotational angular position, a surface corresponding to the tire molding surface of the tire molding mold, and a recess portion corresponding to the protrusion portion; A structure in which a processing electrode is detachably attached to the processing head, prevents overcutting of the protrusion, and is manufactured by replacing a plurality of electrodes with predetermined shapes corresponding to the respective feeding directions. It is. The effect is that manufacturing costs can be reduced and molds with excellent shape and dimensional accuracy can be manufactured.

``Problems to be solved by the invention'' With the primitive method detailed above, it is considered difficult to adopt accurate dimensions, and it is especially difficult to measure the above-mentioned dimensions for this type of cast products that have three-dimensional features. In addition, it is possible to make incorrect measurements, and the marking work requires a high level of skill and a great deal of effort.Furthermore, as mentioned above, it takes a great deal of time and effort to measure accurately. Even so, the marking work required during mold production is time consuming and has many problems, and the current situation is that the marking work is generally dependent on experience and intuition.

Further, as mentioned above, the electroforming method has problems such as difficulty in electrodeposition and complicated work.

Furthermore, in the method for manufacturing a tire molding mold according to the above-mentioned technical literature, although it is possible to produce a mold consisting of one block and to improve the shape and dimensional accuracy, it is still difficult to use the mold for electrical discharge machining. It is still necessary to manufacture the mold separately, and a great deal of effort and skill is required in the process before manufacturing the mold.

"Means for Solving the Problems" In view of the above, the present invention provides a method that can reliably and precisely manufacture a mold for deburring by using the original casting model as it is.
The gist is that a machining gap is formed between the electrode and the deburring mold material, the feed of the electrode is controlled to control the machining gap, and a pulse waveform is formed between the electrode and the deburring mold material. A method of electrical discharge machining in which a voltage is applied, and through this electrical discharge machining, a deburring mold, that is, a lower deburring mold, and an upper deburring mold that is inserted into the lower deburring mold. In the method for manufacturing a mold, a casting original model in which the electrode is mixed with 30 to 40% copper powder is used as it is,
Then, the casting prototype is suspended horizontally from the shank of the electrical discharge machining device with either side facing up, and electrical discharge machining is carried out. When a predetermined depth is reached, the electrode is horizontally A lower mold forming a lower mold for deburring which has an enlarged tapered hole directed downward from the upper surface of the lower mold for deburring through a rocking process in the direction, and has a satin-finished end surface as a whole. The electric discharge machining process is performed using the casting original model as it is for the electrode, and suspending the casting original model horizontally with respect to the shank with one of the casting original models facing up to a predetermined depth. The upper and lower molds for deburring are manufactured by performing electrical discharge machining on the upper mold that constitutes the upper mold for deburring and having a satin-finished surface surface. be.

"Function" Next, to explain the function of the present invention, either one of the cast model 10 mixed with 30 to 40% copper powder is attached as the front side 12 to the shank 4 of the electrical discharge machining device. is the electrode 11. Then, turn on the switch (not shown) on the electrical discharge machine.
When turned ON, the lifting head 3 is lowered one after another and when a predetermined machining gap 1 is formed between it and the deburring mold material 13, a pulse discharge is started by periodically applying a pulse waveform voltage from the electrode 11. As the deburring process progresses, it is deeply carved into the deburring mold material 13. In this case, as the electrode 11 is carved into the mold material 13 for deburring, the volume of the electrode 11 starts to be consumed, so normally when the mold material 13 for deburring is slightly carved, the shank 4 is gradually caused to swing motion. be granted. Therefore, the pulse waveform generated by the electrode 11 is diffused, and an engraving with a slightly larger size than the electrode 11 whose volume has been consumed is formed. Thereafter, such oscillating electric discharge machining is performed downward, and the stroke is gradually increased, and when the removal machining is completed, a pulse discharge from the electrode 11 whose volume has been consumed is generated.
When turned off and the electrode 11 whose volume has been consumed is raised and lowered,
As a result, as shown in the figure, the tapered hole portion 14a expands downward from the upper surface of the deburring mold material 13.
A lower mold hole 14 for deburring is formed, and a lower mold 15 for deburring is manufactured therein.

Next, contrary to the above, shank 4 of the electrical discharge machine
The electrode 21 is attached as the other front side 22 of a casting model 10 mixed with 30 to 40% copper powder. Then, when the switch (not shown) of the electrical discharge machining device is turned on, the elevating head 3 is lowered one by one, and a deburring mold material 23 having an outer shell 23a similar to the original model 10 is moved.
When a predetermined machining interval 1 is formed between the deburring mold material 23, a pulse discharge is performed by periodically applying a pulse waveform voltage from the electrode 21, and the deburring mold material 23 is deeply carved. To go. When the predetermined location is reached, a pulse discharge from the electrode 21 is applied.
When the electrode 21 is turned off and the electrode 21 is raised and lowered, an upper die 24 for deburring is formed on the front side of the outer shell 23a. Incidentally, since the electrode 21 normally begins to lose its volume, the pulse waveform generated by the electrode 21 is changed by applying an oscillating motion to the shank 4 when it is slightly carved into the deburring mold material 23. It is preferable to form an engraving whose size is slightly larger than that of the electrode 1 which has been diffused and whose volume has been consumed. Thereafter, when such rocking electrical discharge machining is performed downward, an upper mold 24 for deburring is formed on the front side of the outer shell portion 23a through engraving. Here, the upper mold 25 for deburring is manufactured.

The deburring lower mold 15 manufactured in this manner is attached to a lower table of a deburring device (not shown) in such a manner that the expanded portion of the enlarged tapered hole portion 14a faces downward. Further, the deburring upper mold 25 is attached to the lifting frame, and the deburring upper mold 24 of the deburring upper mold 25 is inserted into the deburring lower mold hole 14 of the deburring lower mold 15. It will be done.

``Example'' An example of the present invention will be described in detail below based on the drawings. 1 is a column of an electric discharge machining apparatus, 2
is the shank part of that column. A lifting head 3 is built into the shank 2 of the column, and its free end 3a is located outside the shank 2 of the column, and is configured to be able to be raised and lowered relative to the shank 2 of the column. There is. 4 is a shank installed in the lifting head 3, 5 is a motor, 6 is a processing tank,
7 is the base and 8 is the cross table.

The upper and lower molds for deburring castings of the present invention are manufactured using the electric discharge machining apparatus as described above. For example, as shown in FIG. 2 and FIG. As the name suggests, this prototype model 10 uses the original casting as it is, and as will be described later, this prototype model 10 is used as the electrodes 11 and 21.
In principle, upper and lower molds for deburring with no dimensional differences are manufactured. Furthermore, these prototype models 1
30 to 40 for the purpose of improving consumption and energization of 0.
% of copper powder particles may be mixed in, or the size may be reduced by mechanical processing such as cutting and polishing, or chemical treatment using acids, etc., and copper plating corresponding to the amount of this reduction may be applied. Ideally, the electrodes 11 and 21 should be used.

The prototype model 10 manufactured in this way is employed as, for example, the electrode 11 of a lower mold for deburring.
That is, either one of the electrodes 11 is used as the front side 12, and if the front side 12 does not have a horizontal portion 12a, the horizontal portion 12a is provided by cutting or the like.
A shank 4 of the electrical discharge machining device is attached to a. At this time, the deburring mold material 13, which has a model hole 13a roughly corresponding to the deburring lower mold hole, is already attached to the mounting base 9 of the electrical discharge machining apparatus.

When the electrode 11 is attached to the shank 4 in this way, when the switch (not shown) of the discharge pressurizing device is turned on, the elevating head 3 and the shank 4 are lowered, and the electrode 11 is accordingly lowered.
also descends sequentially.

When the electrode 11 descends a predetermined distance, a predetermined machining gap 1 is formed between the electrode 11 and the deburring mold material 13 (state shown in FIG. 6A).
Here, a pulse waveform voltage is periodically applied between the electrode 11 and the deburring mold material 13 to generate a pulse discharge, and the outline of the deburring lower mold hole 14 of the deburring mold material 13 is This electrical discharge machining is sequentially repeated to advance the electrode 11 into the deburring mold material 13, and the deburring lower mold hole 14 corresponding to the electrode 11 is sequentially opened (6th Figure B).

Next, electric discharge machining is repeated, and a blade angle of 90 degrees or less is formed in the lower mold hole 14 for deburring which is opened in the lower mold 15 for deburring to ensure that the burrs are removed from the casting. In order to protect the cutting edge, when the electrode 11 reaches a predetermined dimension within the deburring mold material 13, the shank 4 and the electrode 11 are removed.
gives an oscillating motion to the machine and expands its electrical discharge machining area. Specifically, it is desirable to reach the point where the progress has been made slightly from the upper surface (state shown in Fig. 6 (c)), and from then on, such oscillating electric discharge machining is performed downward, and the stroke is gradually increased. When the punching process is completed in this manner, an enlarged tapered hole portion 14a extending downward from the upper surface portion of the lower deburring mold 15 is formed (the state shown in FIG. 6D).

Therefore, the pulse discharge from electrode 11 is turned off,
When the electrode 11 is moved up and down, as shown in FIG. 6E, a lower mold 15 for deburring is manufactured which is provided with a lower mold hole 14 for deburring having an enlarged tapered hole portion 14a. .

Thereafter, by removing the lower mold 15 for deburring from the mounting base 9, the production of the lower mold 15 for deburring is completed.

In the second invention, as described above, the lower mold hole 1 for deburring is formed in the mold material 13 for deburring by electric discharge machining.
4 is formed, the so-called deburring mold material 1
3. Perform the punching process and make the lower mold 15 for deburring.
form. After that, the lower mold 15 for deburring
The shank 4 is pulled upward from the bottom of the lower mold hole 14 for deburring formed in the shank (that is, the outward movement of the shank 4 is utilized), and the electrode 11 is swung in the horizontal direction. Through dynamic machining, an enlarged tapered hole portion 14a is formed in the lower mold hole for deburring of the lower mold for deburring 15 from the upper part toward the lower part, so that the mounting base 9
By removing the lower mold 15 for deburring, the production of the lower mold 15 for deburring is completed.

On the other hand, the prototype model 1 manufactured as described above
0 is employed as the electrode 21. That is, this electrode 2
1 as the front side 22, and if there is no horizontal part 22a on this front side 22, cut it etc. to make the horizontal part 2.
2a is provided, and a shank 4 of the electrical discharge machining device is attached to this horizontal portion 22a. At this time, the deburring mold material 23, which has an outer shell 23a that roughly corresponds to the punches of the upper mold for deburring, has already been attached to the mounting base 9 of the electrical discharge machining device (see Fig. 7, Fig. 7). condition).

After the electrode 21 is attached to the shank 4 in this way, when the switch (not shown) of the electrical discharge machining device is turned on, the elevating head 3 and the shank 4 descend, and as a result, the electrode 21
also descends sequentially.

When the electrode 21 descends a predetermined distance, a predetermined machining gap 1 is formed between the electrode 21 and the deburring mold material 23 (state shown in FIG. 7B).
Here, a pulse waveform voltage is periodically applied between the electrode 21 and the deburring mold material 23 to generate a pulse discharge, and the deburring upper mold 24 is formed on the front side of the deburring mold material 23. The upper mold surface of the similar type is subjected to electric discharge machining, and this electric discharge machining is sequentially repeated to advance the electrode 21 into the deburring mold material 23.
An upper mold surface similar to the deburring upper mold 24 corresponding to the electrode 21 is provided on the front side of the deburring mold material 23 (the state shown in FIG. 6C).

Although such electrical discharge machining is repeated, when the electrode 21 has progressed to a predetermined size within the deburring mold material 23 and when the electrode 21 is worn out, the shank 4 and the electrode 21 are subjected to a rocking motion. and expand its electrical discharge machining area. Thereafter, such rocking electrical discharge machining is performed downward, and the stroke is gradually increased, and when the engraving process is completed, the front side of the upper mold 25 for deburring has a satin-like processed surface side. The deburring upper mold 24 is formed (state shown in FIG. 7D).

Therefore, the pulse discharge from the electrode 21 is turned off,
When the electrode 21 is moved up and down, as shown in FIG. 7E, an upper mold for deburring 25 having an upper mold for deburring 24 is manufactured.

Thereafter, by removing the upper mold 25 for deburring from the mounting base 9, the manufacture of the upper mold 25 for deburring is completed.

"Effects of the Invention" As described in detail above, the present invention is an electrical discharge machining method in which a casting model is used as an electrode as it is, and this model is used as an electrode. It has the effect of increasing accuracy and can greatly contribute to speeding up and making deburring work more efficient. In addition, since the original casting model is used as the electrode, there is no need for design work such as measuring and marking, or processing work such as cutting and polishing, which is required in the past, which simplifies mold production. This will greatly help speed up the process. Further, since a clearance is created between the lower mold for deburring and the upper mold for deburring through the rocking motion processing of the prototype, the cutting edge can be protected and the deburring operation can be performed reliably.

[Brief explanation of the drawing]

The drawings show an example of the present invention, and FIG. 1 is a sectional view showing an example of a device used in the present invention, and FIG.
The figure is a perspective plan view showing an example of the prototype model, FIG. 3 is a rear perspective view showing an example of the prototype model, FIG. 4 is a perspective plan view showing an example of the electrode and the shank, and FIG. 5 is the perspective view of the electrode and the shank. 6th rear perspective view showing an example of
FIGS. 7A to 7E are diagrams for explaining the manufacturing process of the lower mold for deburring, and FIGS. 7A to 7E are diagrams for explaining the manufacturing process of the upper mold for deburring. 1: Column, 2: Shank part of column, 3: Elevating head, 4: Shank, 5: Motor, 6: Processing tank, 7: Base, 8: Cross table, 9: Mounting stand, 10: Prototype model, 11, 21: electrode, 12,
22: Front side, 12a, 22a: Horizontal part, 13, 2
3: Deburring mold material, 13a: Model hole, 14:
Lower die hole for deburring, 14a: Expanded taper hole part,
15: Lower mold for deburring, 23a: Outer shell, 2
4: Upper mold for deburring, 25: Upper mold for deburring.

Claims (1)

[Scope of Claims] 1 A processing gap is formed between an electrode and a deburring mold material, the feeding of the electrode is controlled to control the processing gap, and a processing gap is formed between the electrode and the deburring mold material. A method of electrical discharge machining in which a pulse waveform voltage is applied to In the method for manufacturing a commercial mold, a casting prototype is used as it is for the electrode, and the casting is suspended in a horizontal state with respect to the shank with one of the casting prototypes facing up, Electric discharge machining is performed, and when the specified depth is reached,
An enlarged tapered hole portion directed downward is formed from the upper surface of the lower mold for deburring through a horizontal rocking process of the electrode, and the lower mold for deburring has a satin-finished end surface as a whole. In the electric discharge machining process of the lower mold, using the original casting model for the electrode as it is, and suspending the original casting model in a horizontal state with respect to the shank so that one of the casting original models faces the front side, Electrical discharge machining is performed to the specified depth,
Production of a mold for deburring castings in electric discharge machining, characterized in that upper and lower molds for deburring are manufactured by an electric discharge machining process of an upper mold constituting an upper mold for deburring having a satin-finished front side. Method. 2 The copper powder of the casting model that will become the electrode is 30 ~
A method for manufacturing a mold for deburring a casting in electrical discharge machining according to claim 1, wherein the metal is mixed in an amount of 40%. 3. A method for manufacturing a mold for deburring a casting in electrical discharge machining according to claim 1 or 2, wherein a model hole similar to the original model is previously formed in the deburring mold material. 4. A casting for electrical discharge machining according to claim 1, in which the entire outer circumferential surface of the master model is reduced in size by etching, electrolytic polishing, or other methods, and copper plating treatment is applied in an amount corresponding to the amount of reduction in size. A method for manufacturing a deburring mold. 5. Forming a machining gap between the electrode and the deburring mold material, controlling the feeding of the electrode to control the machining gap, and applying a pulse waveform voltage between the electrode and the deburring mold material. A method of electric discharge machining, in which a deburring mold, that is, a deburring lower mold, and a deburring upper mold to be inserted into the deburring lower mold are manufactured through this electric discharge machining. In the method, the casting prototype is used as it is as the electrode, and after the casting is suspended in a horizontal state with respect to the shank with one of the casting prototypes facing up, electrical discharge machining is performed in sequence. Then, when performing a punching process on the deburring mold material to form a deburring lower mold hole in the deburring mold material, and pulling up the casting prototype from the deburring lower mold hole, Through horizontal rocking processing of this casting prototype model, an enlarged tapered hole section directed downward from the top is formed in the deburring lower mold hole of the deburring lower mold, and a satin-finished end surface is formed on the entire surface. an electric discharge machining process of a lower mold constituting a lower mold for deburring, and using a casting original model as it is for the electrode, and placing one of the casting original models in a horizontal state with respect to the shank; Hang it so that the front side is
The upper and lower molds for deburring are manufactured by performing electric discharge machining to a portion reaching a predetermined depth, and the electric discharge machining process of the upper mold constituting the upper mold for deburring having a satin-finished surface surface. A method for manufacturing a mold for deburring castings in electrical discharge machining. 6 Copper powder is added to the casting model that will become the electrode.
A method for manufacturing a mold for deburring castings in electric discharge machining according to claim 5, wherein the metal is mixed in an amount of 40%. 7. A method for manufacturing a mold for deburring a casting in electrical discharge machining according to claim 5 or 6, wherein a model hole similar to the original model is previously formed in the deburring mold material.