JPH01197029A - Insert split die and its manufacture - Google Patents

Abstract

PURPOSE:To enable the die manufacture by non-discharging and to improve the accuracy and die service life by dividing a bending recessed part into the die having a linear recessed part by sectioning it at the bending part. CONSTITUTION:The outer peripheral part 41 of a bevel gear 4 is regulated by an annular 1st die 1 in a bevel gear die, for instance. A 2nd die 2 is then formed in annular shape on the whole corresponding to the inner periphery of the 1st die 1 and the linear inclined recessed part 21 regulating a bevel gear inclining tooth part 42 and the rise part 22 regulating a bevel gear inclining root part 43 are alternately formed on the upper end peripheral face thereof. Moreover, a 3rd die 3 is formed in annular shape on the whole corresponding to the inner periphery of the 2nd die 2, and on the upper end peripheral face thereof the linear inclining recessed part 31 regulating a bevel gear horizontal tooth part 44 and the rise part 32 regulating the inclining root part continued to the bevel gear inclining root part 43 are formed. Consequently, the working is remarkably facilitated because the die recessed part of the bending part is divided so as to become in a linear part.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a split mold used in the field of female molds that are subjected to electrical discharge machining using electrodes of the same shape, such as bevel gears, and a method for manufacturing the same.

(Prior art and its problems) When manufacturing the bevel gear etc. shown in Fig. 4, generally, as shown in Fig. 5, a pre-processed female mold material W is inserted and fixed into the mold holder H (a). (see), electrical discharge machining is performed 3 to 4 times using electrode E, which has approximately the same shape as the bevel gear (see (b)), and finally LP finishing is applied to produce a female mold, but many There are problems.

That is, ■den el! It takes a lot of time to create.

■ Machining accuracy is poor, and not only does it take a long time to finish the electrical discharge machined surface, but the finishing accuracy is also likely to deteriorate.

■The electric discharge machining process is long and tends to be expensive, and the mold life is short because a white layer remains on the mold due to electric discharge machining. ■If the mold material is a superhard alloy, there is a drawback that electrical discharge machining is difficult.

Therefore, other machining methods have been proposed in place of electric discharge machining, but it is difficult to machine the bent parts of female molds where the teeth change two-dimensionally, such as in bevel gears. is the current situation.

(Problems to be Solved) Therefore, the present invention aims to provide a bevel gear mold structure that can be manufactured by non-discharge machining and a preferable manufacturing method thereof. It is difficult to process the female mold at the bent part, but if the mold is divided so that the mold concave part becomes a straight part at the bent part, it has been found that it can be manufactured by, for example, polishing. The present invention has now been completed.

(Configuration to Achieve the Problems) The present invention provides a bevel gear mold consisting of a mold holder and an insert mold that is inserted and fixed into the mold holder to form a bevel gear part. A second mold having a linearly inclined concave portion for regulating the bevel gear inclined tooth portion, and a third mold having four linearly inclined portions for regulating the bevel gear horizontal tooth portion are assembled. The gist of the insert is in the split mold.

Although the present invention is mainly directed to female molds for bevel gears,
Since it is based on dividing the bent recess at the bent part into molds having linear recesses, it has the same two-dimensional change and can be manufactured by electric discharge machining using electrodes with a similar shape to the product. It can be used for female molds.

In the present invention, there is no particular restriction on the division form of the raised part of the mold, but considering the strength of the raised part at the divided part, it is preferable to avoid edges that form an acute angle. It is preferable to consider ensuring the integrity of the molds when assembling them. Therefore, if the end of the raised part of the second mold on the third mold side is formed to cover the end of the raised part of the third mold on the second mold side, the strength of the end of the raised part is increased. This is a preferable form because it also ensures integrity during assembly.

According to the above-mentioned insert split mold, the mold recess is divided into straight parts at the bending part, which is considered difficult to machine, so machining becomes extremely easy, so even if electrical discharge machining is used, the electrode Formation becomes easy, and a cutting method can also be employed. However, in any case, a final polishing step is required, so it is preferable to perform all steps by polishing. Therefore, the present invention provides an insert mold that is inserted and fixed into a mold holder and forms a bevel gear part, and has a first mold part that regulates the outer peripheral part of the bevel gear, and a first mold part that has a linearly inclined recess that regulates the bevel gear inclined tooth part. 2 mold parts and a 3rd mold part that has a linearly inclined recess that regulates the horizontal teeth of the bevel gear! +1, a bevel gear mold whose gist is to form the linearly inclined concave portion by a polishing method! !
! ! It is also a way of capturing the 1st construction method.

Hereinafter, the present invention will be described in detail based on specific examples shown in the accompanying drawings.

(Example) Fig. 1 is a plan view showing the insert mold part of a female bevel gear mold according to the present invention, and Fig. 2 is a cross-sectional view taken along the line ■-■.
As shown in FIG. 3, a ring-shaped first mold (1) inserted into a mold holder H is inserted into a second mold (2) and a third mold (3) as shown in FIG. ) in the assembled state to obtain the fourth
The bevel gear shown in the figure can now be manufactured.

Specifically, the first mold (1) regulates the outer circumference 41 of the bevel gear (4) and has a ring shape. Next, the second mold (2) is formed into a ring shape as a whole corresponding to the inner periphery of the first mold (1), and has a linearly inclined recess 21 on its upper peripheral surface that regulates the bevel gear inclined teeth 42. The raised portions 22 that restrict the bevel gear inclined valley portions 43 are alternately formed. Furthermore, - the third mold (3) is the second mold (
1) is formed into a ring shape as a whole corresponding to the inner circumference of
On the upper end circumferential surface thereof, linearly inclined recesses 31 for regulating the bevel gear horizontal tooth portion 44 and raised portions 32 for regulating the inclined valley portion continuous to the bevel gear inclined valley portion 43 are alternately formed.

The raised part 22 of the second mold has a substantially rectangular shape, and the raised part 22 of the second mold has a substantially rectangular shape.
Continuing with the triangular raised portion 32 of the mold, the second
An end 22a of the raised portion 22 of the mold on the third mold side forms a substantially right angle, and is formed to cover an end 32a of the third mold on the second mold side.

The first to third molds to be divided are manufactured by preforming a predetermined material, and then polishing and boring the linearly inclined recesses 21 and 31, and polishing and molding the protrusions 22 and 32.

(Effects of the Invention) As is clear from the above description, according to the present invention, in a bevel gear mold consisting of a mold holder and an insert mold inserted and fixed into the mold holder to form a bevel gear part, conventional A bent recess, which could only be produced by electrical discharge machining, is divided at the bending part, and the insert mold has a first mold that restricts the outer circumference of the bevel gear, and a second mold that has a linearly inclined recess that restricts the bevel gear's inclined teeth. Since the mold and the third mold having a linearly inclined recess for regulating the horizontal teeth of the bevel gear are assembled and constructed separately, the mold can be manufactured by non-discharge machining. As a result, a female mold with high precision can be manufactured in a short time and at a low cost, and the life of the mold can be improved, compared to the conventional monolithic manufacturing using electric discharge machining. Moreover, it is possible to manufacture molds using super hard alloy materials in response to the demands of the times.
Its utility value in mold production is immeasurable.

Of course, even if the electrical discharge machining method is used as in the past, it also has the advantage of solving the difficulties of electrode production.

In particular, in the present invention, both electric discharge machining and cutting methods can be employed, but since the entire process of mold manufacturing can be performed by the polishing method, mold manufacturing can be carried out efficiently. .

The present invention has been described above using the production example of a bevel gear as a specific example, but it is widely applicable to female molds that have the same two-dimensional change as bevel gears and are manufactured by electric discharge machining using electrodes with a similar shape to the product. It is possible.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing the insert mold portion of the bevel gear female mold according to the present invention, and FIG. 2 is a cross-sectional view taken along the line n-■.
Fig. 3 is a sectional view showing the assembled state of the insert mold shown in Fig. 1, Fig. 4 is a perspective view of a bevel gear manufactured using the above mold, and Fig. 5 Fa) and (b) are views of the conventional mold. It is a process diagram showing an example of mold manufacturing. (ll...first mold, (2)...second mold, (3)...
Third mold, 22.32... linear recess

Claims (3)

[Claims] (1) In a bevel gear mold consisting of a mold holder and an insert mold inserted and fixed into the mold holder to form a bevel gear part, a first
The mold is divided into a second mold having a linearly inclined recess for regulating the bevel gear's inclined teeth, and a third mold having a linearly inclined recess for regulating the bevel gear's horizontal teeth. Features a split insert mold. (2) The end of the raised part of the second mold on the third mold side covers the end of the raised part of the third mold on the second mold side, and is formed so as to be continuous. The bevel gear mold according to item 1 above. (3) An insert mold that is inserted and fixed into the mold holder and forms a bevel gear part; a first mold part that regulates the outer peripheral part of the bevel gear; and a second mold that has a linearly inclined concave part that regulates the bevel gear inclined tooth part. A method for manufacturing a bevel gear mold, characterized in that the mold is divided into a second mold part and a third mold part having a linearly inclined recess that regulates a bevel gear horizontal tooth part, and the linearly inclined recess is formed by a polishing method.