JPH0751788A - Plastic working method for gear or gear-like material - Google Patents

Abstract

PURPOSE:To provide a method by which ironing is not executed at the opening edge part of a die hole when a gear or gear-like material formed from a blank with a pinch and a counter punch n the die member is ejected with the counter punch. CONSTITUTION:At the time of compressing the blank 20 with the punch 2 and the counter punch 6 in the die hole 11 of the die member 5, the opening edge part 11A of the die hole 11 is elastically shrinkage-deformed with a tapered member 14. A spur gear 21 with crowning is formed from the blank 20 in the die hole 11, and at the time of ejecting the gear 21 with the counter punch 6, the elastic shrinkage-deformation at the opening edge part 11A is released and the ironing is not executed to teeth of the gear 21 at the opening edge part 21A and the gear 21 can be made to eject.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a gear or a gear-like material by plastically working a material in a die member by means of a punch and a counter punch, for example, a spur gear with crowning, a helical gear, and Can be used for molding an article having a protrusion protruding outward on the outer periphery.

[0002]

BACKGROUND ART FIG. 10 shows a conventional apparatus for plastically working a gear from a material, which is a forging die set in a press machine. This mold includes a punch 102 attached to a slide 101 that moves up and down, and a bolster 1.
03 includes a die member 105 in a case 104 and a counter punch 106, and the die member 105 is constantly elastically urged toward the punch 102 by an elastic member 107, and the counter punch 106 can be pushed up by an eject pin 108. Has become.

The die member 105 is composed of an upper die portion 109 and a lower container portion 110, and the die portion 109 has a die hole 111 having an opening end portion 111A on the punch 102 side.
And a container hole 112 communicating with the die hole 111 is provided in the container portion 110.
The counter punch 106 having the upper part inserted in 2 has a die hole 1
11 can be reached.

As shown in FIG. 10A, the container hole 112
A material 120 having a vertical dimension longer than that of the die hole 111 is accommodated and set therein.
Can be received at. Thereafter, as shown in FIG. 10B, the punch 102 descends, the punch 102 pushes down the die member 105 against the elastic member 107, and the counter punch 106 compresses the material 120. As a result, the material 120 overhangs and plastically deforms in the outer peripheral direction, and the die hole 11 formed in a shape corresponding to the gear to be produced is formed.
Fill within 1. As a result, the gear 12 is
1 is molded, and the gear 121 is ejected from the die hole 111 by raising the punch 102 and then pushing up the counter punch 106 with the eject pin 108.

[0005]

FIG. 11 shows a die hole 11
2 is a cross-sectional view of a tooth 121A portion of the gear 121 in FIG. When the gear 121 is a spur gear with crowning, the tooth 121A of the spur gear 121 with crowning has the largest tooth thickness in the substantially central portion, and the tooth 121A has a shape that is slightly curved and protrudes outward. . When the gear 121 having such a tooth shape is ejected from the die hole 111 by the counter punch 106, the tooth thickness portion of the tooth 121A is ironed at the opening end portion 111A of the die hole 111 at the time of this ejection, and the tooth 121A of the tooth 121A is ironed. There is a problem that a predetermined dimensional accuracy cannot be obtained.

Further, since excessive stress acts on the opening end 111A when the gear 121 is ejected, there is a problem that the opening end 111A is easily damaged.

The present invention was invented to solve such a problem, and there is Japanese Patent Publication No. 62-34040 as a prior art which seems to be similar to the present invention. For the purpose of shrinking and deforming the die member as a whole to form a counter taper over the entire tooth, and for forming the gear stepwise from a raw material through a plurality of forging steps. However, it is not always appropriate as a device for solving the above-mentioned conventional problems.

An object of the present invention is to prevent the molded product from being ironed at the opening end of the die hole when ejecting the molded product from the die member, and thus a molded product with a predetermined accuracy can be obtained. Another object of the present invention is to provide a plastic working method for a gear or a gear-like material in which the open end of the die hole is not damaged.

[0009]

The method according to the present invention comprises:
A die hole having a shape corresponding to the gear or gear-like object to be produced is formed on the die member with the opening end facing the punch side, and the counter punch is inserted into the die member from the side opposite to the opening end of the die hole. Then, a material having a larger vertical dimension than the die hole is housed in the die member, the material is received by the counter punch, and then the punch is moved to the die member side to compress the material with the punch and the counter punch. By forming a gear or gear-like object in the die hole by filling the die hole with deformed material, the counter punch is moved to the punch side by the eject member after separating the punch from the die member. In the plastic working method of the gear or the gear-like object, the gear or the gear-like object is ejected from the inside of the die hole. The end of the opening of the die is elastically contracted and deformed more than other parts, and this elastically contracted deformation is continued until the material is expanded and deformed in the outer peripheral direction to fill the die hole, and the gear or gear formed in the die hole. It is characterized in that the opening end of the die hole is enlarged when ejecting the object with a counter punch.

There are various forms for causing the elastic contraction deformation. For example, a pressure receiving portion is provided around the opening end of the die hole in the die member, and an elastic contraction deformation is caused by applying a pressing force in the inner circumferential direction to the pressure receiving portion by a taper member provided on the punch side. A groove containing a fluid member such as oil is provided around the opening end of the die hole in the die member, and the fluid member is pressed by a pressing member on the punch side to generate a pressing force in the inner circumferential direction. This causes elastic contraction deformation, the outer peripheral portion of the die member is supported by a pressure receiving member arranged on the counter punch side of the die member, and when the pressing force from the punch is received by the die member, the entire die member is pressed. There is a case where elastic contraction deformation is generated by deforming so as to warp.

Further, the container part for containing the material to be compressed by the punch and the counter punch may be provided on the die member side or may be provided on the punch side.

Further, the molded product molded by the method according to the present invention is not limited to the spur gear with crowning,
For example, a helical gear may be used. Further, the invention is not limited to a gear, and may be one having a protrusion protruding outward on the outer peripheral portion. In short, the present invention can be used for producing a gear or a gear-like object.

[0013]

When the material is compressed by the punch and the counter punch in the die member, the opening end of the die hole is elastically contracted and deformed more than other parts, and the elastic contraction is generated in the die hole. Filled with deformed material that protrudes outward. When ejecting the gear or gear-like material obtained from the material in the die hole with the counter punch, the opening end of the die hole expands and the elastic contraction deformation is released, so the gear or gear-like object is ejected at the time of this ejection. Is not ironed at the opening end, and no excessive stress acts on the opening end.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The apparatus of each embodiment according to the present invention will be described below with reference to the drawings. FIG. 1 shows an apparatus according to the first embodiment. A punch 2 is attached to the slide 1 that moves up and down, and a bolster 3 is provided with a die member 5 incorporated in a lower case 4 and a counter punch 6. These are vertically movable, the die member 5 is always elastically biased toward the punch 2 by an elastic member 7 by a spring, and the counter punch 6 can be pushed up by an eject pin 8 which is an eject member. The die member 5 is composed of an upper die portion 9 and a lower container portion 10. The die portion 9 is provided with a die hole 11 having an opening end portion 11A on the punch 2 side. A container hole 12 communicating with the counter punch 6 is provided so that the counter punch 6 can reach the die hole 11 through the container hole 12. Die part 9
The die hole 11 formed in 1 corresponds to the shape of the spur gear with crowning to be produced.

An upper case 13 is attached to the slide 1, and a taper member 14 is provided in the upper case 13 so as to be vertically movable outside the punch 2.
An elastic member 4 is always elastically biased toward the die member 5. An inclined surface 14A is formed on the lower side surface of the taper member 14 on the punch 2 side, and the inclination direction of the inclined surface 14A is
As the inclined surface 14A extends toward the die member 5, the direction is toward the outer peripheral side of the die member 5. In the die member 5, in the outer periphery of the opening end 11A of the die hole 11,
A pressure receiving portion 5A protruding upward is formed, and an outer peripheral surface 5B of the pressure receiving portion 5A has an inclined surface 14A of the taper member 14.
And the tilt direction and tilt angle correspond to each other.

A material 20 having a larger length than the die hole 11 is accommodated and set in the container hole 12 in the die member 5, and the material 20 is received by the counter punch 6. 2A to 2D, the material 20 is punched 2 and the counter punch 6 is used.
FIG. 3 is a diagram showing the work steps for plastically working in the above to produce a spur gear with crowning in the order.

In FIG. 2A, when the punch 2 approaches the die member 5 as the slide 1 descends, the taper member 14
The inclined surface 14A starts to engage with the outer peripheral surface 5B of the pressure receiving portion 5A, and the pressure receiving portion 5A receives a pressing force from the taper member 14 in the inner peripheral direction. As shown in FIG. 2B, when the punch 2 is further lowered, the punch 2 holds the die member 5 and the elastic member 7 while the pressure receiving portion 5A receives the pressing force from the taper member 14 in the inner circumferential direction.
As a result, the material 20 is compression-plastic-processed by the punch 2 and the counter punch 6, and is expanded and deformed in the outer peripheral direction to fill the die hole 11.

As described above, when the punch 2 descends, the taper member 14 exerts a pressing force on the pressure receiving portion 5A in the inner circumferential direction, so that the pressure receiving portion 5A elastically contracts in the radial direction and also in the circumferential direction. 3 also elastically contracts, and as shown in FIGS. 3 and 4, the opening end 11A of the die hole 11 elastically contracts and deforms by the compressive force F shown by the arrow. This elastic contraction deformation is largest at the opening end portion 11A, and elastic contraction deformation occurs even in a portion below the opening end portion 11A, but this elastic contraction deformation amount becomes gradually smaller as it moves downward from the opening end portion 11A. When such elastic contraction deformation is completed, the overhang deformation of the material 20 due to the compressive load of the punch 2 and the counter punch 6 is completed, and the shape of the die hole 11 at this time is the shape with crowning to be produced. Since it exactly matches the shape of the spur gear 21, the die hole 11
The gear 21 is molded therein.

After that, when the punch 2 rises, C of FIG.
As shown in FIG. 5, the die member 5 is raised to the upper limit position by the elastic force of the elastic member 7, and at this time, the pressure receiving portion 5A moves to the taper member 1
Since 4 is separated, the elastic contraction deformation generated in the pressure receiving portion 5A is released, and the opening end portion 11A of the die hole 11 is enlarged as shown in FIG. After that, as shown in FIG. 2D, the eject pin 8 pushes up the counter punch 6, and the counter punch 6 moves from the die hole 11 to the spur gear 21 with crowning.
To eject.

When the gear 21 is ejected by the counter punch 6, since the opening end 11A of the die hole 11 is enlarged, the gear 21 is ejected without ironing the teeth 21A at the opening end 11A. Become. Therefore, the gear 21 is produced with a sufficiently high accuracy, and the opening end 11 is ejected when the gear 21 is ejected.
Since an excessive stress does not act on A, the opening end 1
There is no accident that 1A is damaged.

In the first embodiment described above, the means N for elastically contracting and deforming the opening 11A of the die hole 11 is configured to include the taper member 14 and the pressure receiving portion 5A.

Next, another embodiment of the present invention will be described. In the following description, the same reference numerals will be given to the members and the parts that have the same parts as those already described in the above embodiment, and the description thereof will be simplified or omitted. FIG. 6 shows a second embodiment of the present invention. In this embodiment, the upper case 1 attached to the slide 1
3, a taper member 34 having a downwardly extending projection 34A is provided so as to be vertically movable, and the taper member 34 is given a downward elastic biasing force by an elastic member 35.
The outer surface of the protruding portion 34A opposite to the punch 2 is an inclined surface 3
4B, and this inclined surface 34B is the inclined surface 1 of FIG.
Like 4A, it is inclined with respect to the moving direction of the punch 2, but the inclination direction is opposite to that of the inclined surface 14A. The die member 25 is provided with a pressure receiving portion 25A that protrudes straight upward on the outer periphery of the opening end portion 11A of the die hole 11.
Inner and outer members 36, 37 are fixed to the die member 25 on the outside of the pressure receiving portion 25A, and a gap is provided between the inner member 36 and the outer member 37 into which the protrusion 34A of the taper member 34 can be inserted. The inner surface 37A of the outer member 37 is an inclined surface, and its inclination direction and inclination angle are the same as those of the inclined surface 34B of the protrusion 34A.

When the punch 2 descends, the protrusion 34A enters between the inner member 36 and the outer member 37, and the protrusion 34A is elastically deformed toward the pressure receiving portion 25A by the load from the inner side surface 37A acting on the inclined surface 34B. As a result, a pressing force in the inner circumferential direction is generated from the inner member 36 to the pressure receiving portion 25A. Therefore, the opening end portion 11 of the die hole 11 is similar to the embodiment of FIG.
A is elastically contracted and deformed before and during the compression processing of the material 20 by the punch 2 and the counter punch 6. This elastic contraction deformation is released when the punch 2 rises, and the die hole 1
1 returns to its original shape.

Therefore, the elastic contraction / deformation means N of the second embodiment includes the taper member 34, the pressure receiving portion 25A, and the inner / outer member 3.
6, 37 are included.

FIG. 7 shows a third embodiment. Upper case 13
A pressing member 54 elastically biased downward by an elastic member 55 is provided to be movable up and down, and a groove 56 is provided in the die member 45 around the outside of the die hole 11. The groove 56 may be a ring-shaped one continuously formed around the die hole 11 or may be a plurality of individual grooves independently provided around the die hole 11. A fluid member 57 made of oil or a soft metal such as lead or copper is provided in the groove 56.
Are filled and the piston 58 is arranged thereon.

When the punch 2 descends, the pressing member 54 compresses the fluid member 57 via the piston 58, so that this compressive load is applied to the die hole 11 and the groove 56 in the die member 45.
This acts as an inner circumferential pressing force on the intermediate portion 45A between and, so that the opening end 11A of the die hole 11 is elastically contracted and deformed. When the punch 2 moves up, this elastic contraction deformation is released.

For this reason, the elastic contraction / deformation means N in the third embodiment includes the pressing member 54, the groove 56, and the fluid member 5.
It is configured to include 7.

FIG. 8 shows a fourth embodiment. The outer peripheral portion 65A of the die member 65 is thin and has a smaller vertical dimension than the inner peripheral portion (central portion) where the die hole 11 is formed, and the counter punch 6 is formed in the lower case 4 more than the die member 65.
A pressure receiving member 74 is vertically movably arranged on the side, and the pressure receiving member 74 is always elastically biased toward the punch 2 by an elastic member 75 having a large elastic force while supporting the outer peripheral portion 65A. The elastic member 7 that elastically biases the die member 65
Alternatively, the elastic member 75 may elastically bias both the die member 65 and the pressure receiving member 74 toward the punch 2.

When the punch 2 descends, the die member 65 that receives the pressing force from the punch 2 at the peripheral portion of the die hole 11 descends, and the outer peripheral portion 65A is supported upward by the pressure receiving member 74. The peripheral portion of the die hole 11 of 45 is elastically lowered with respect to the outer peripheral portion 65A,
The die member 6 so that A is elastically deformed upward and in the inner peripheral direction.
Since 5 is warped and deformed as a whole, the opening end 11A of the die hole 11 is elastically contracted and deformed. When the punch 2 moves up, this elastic contraction deformation is released.

Therefore, the elastic contraction / deformation means N in the fourth embodiment includes the pressure receiving member 74.

In each of the above embodiments, the die members 5, 25,
45 and 65 are elastic members which are elastically urged toward the punch 2 side, and the container holes 12 of the container portion 10 for inserting the material 20 are formed in these die members. The container member in which the material 20 to be compressed in 6 is put may be provided not on the die member side but on the punch 2 side.

FIG. 9 shows such an embodiment. The die member 85 in the lower case 4 is placed on the pedestal 87, so that the die member 85 is arranged immovably in the moving direction of the punch 2. A container member 89 is provided on the outer side of the punch 2 so as to be vertically movable, and the container member 89 is elastically biased toward the die member 85 by an elastic member 87.

As shown in FIG. 9A, after the material 20 is stored in the die hole 11 of the die member 85 while being received by the counter punch 6, the slide 1 is lowered and the punch 2 and the like are also lowered. , The upper portion of the material 20 protruding upward from the die member 85 enters the container hole 92 of the container member 89, and the punch 2 and the like are further lowered,
As shown in FIG. 9B, the outer peripheral surface of the material 20 is a die member 85.
While being restrained by the container member 89, the punch 2 and the counter punch 6 perform compression processing, and the material 2 is held in the die hole 11.
The gear 21 is molded from 0.

The elastic contraction / deformation means N in this embodiment has the same structure as in the first embodiment. That is, this means N is provided with the elastic member 9 on the punch 2 side.
5, the taper member 94 is provided so as to be movable up and down while being elastically biased, and the opening end 11 of the die hole 11 is formed in the die member 85.
The pressure receiving portion 85A is formed so as to project upward around the outer periphery of A, and the inclined surface 94A of the taper member 94 and the outer peripheral surface 85B of the pressure receiving portion 85A that come into contact with each other when the punch 2 descends. The same tilt direction and the same tilt angle.

The configuration in which the container member is provided on the punch 2 side as shown in FIG. 9 can also be adopted in the apparatus of each of the above-described embodiments.

Further, although the above embodiment is for forming a spur gear with crowning, the present invention can be used for forming a helical gear with crowning. Generally, the helical gear formed in the die hole of the die member is itself rotated and ejected by the thrust force of the counter punch. By providing a rotating member such as a bearing, the helical gear can be reliably rotated and projected.

The present invention can also be used for forming a gear with holes by providing a mandrel on the punch side. The present invention is a gear other than the above or a molded product other than the gear. It can also be used to produce a gear-shaped article having an outwardly projecting protrusion on its outer periphery.

[0038]

According to the present invention, when the material is being compressed by the punch and the counter punch in the die member, the opening end of the die hole is elastically contracted and deformed, and the die hole is projected and deformed in the outer peripheral direction. When ejecting a gear or gear-like object molded from the material filled in the die hole with a counter punch, the opening end of the die hole is expanded and elastic contraction deformation is released, so the gear is not ejected during this ejection. Or the gear is not ironed at the open end,
Therefore, it is possible to achieve high-precision molding of a gear or a gear-like object, and since excessive stress does not act on the opening end, it is possible to prevent damage to the opening end.

[Brief description of drawings]

FIG. 1 is a front sectional view showing an apparatus according to a first embodiment for carrying out the method according to the present invention.

FIG. 2 is a work process chart showing the forming work of a gear or a gear-like object by the apparatus of the first embodiment in the order.

FIG. 3 is a partial cross-sectional view of a die member showing that the open end of the die hole is elastically contracted and deformed.

4 is a sectional view taken along line IV-IV in FIG.

5 is a partial cross-sectional view of the die member showing that the elastic contraction deformation of FIG. 3 is released when the gear or the gear-like object is ejected from the die member.

FIG. 6 is a front sectional view showing an apparatus according to a second embodiment.

FIG. 7 is a front sectional view showing an apparatus according to a third embodiment.

FIG. 8 is a front view showing the device of the fourth embodiment.

FIG. 9 is a front sectional view showing the apparatus of the embodiment in which the container member is provided on the punch side, showing the raw material before compression processing and during compression processing.

FIG. 10 is a front sectional view showing a conventional device before and during compression processing of a material.

11 is a partially enlarged cross-sectional view of the die member in FIG.

[Explanation of symbols]

1 Slide 2 Punch 3 Bolster 5, 25, 45, 65, 85 Die member 5A, 25A, 85A Pressure receiving part 6 Counter punch 7 Elastic member 8 Eject pin which is an eject member 9 Die part 10 Container part 11 Die hole 11A Open end part 12 container hole 14, 34, 94 taper member 14A, 34B, 94A inclined surface 20 material 21 spur gear with crowning that is a gear or gear-like object 54 pressing member 56 groove 57 fluid member 74 pressure receiving member 89 container member N elastic shrinkage Deformation means

Claims (5)

[Claims] 1. A die member is formed with a die hole having a shape corresponding to a gear or a gear-like member and having an opening end on the punch side, and a counter punch is formed on the die member in a direction opposite to the opening end. Inserted into the die member, a material having a size longer than the die hole is accommodated in the die member, the material is received by the counter punch, and then the punch is moved to the die member side to move the material to the punch. By compressing with a counter punch, the die hole is filled with the material that is deformed so as to project outward and the gear or gear-like object is formed in the die hole, and the punch is separated from the die member. After that, the counter punch is moved to the punch side by an ejecting member to eject the gear or gear-like object from the die hole by plasticizing. In the working method, during compression processing of the material, the opening end of the die hole is elastically contracted and deformed more than other parts, and this elastic contraction deformation is caused by the overhang deformation of the material into the die hole in the outer peripheral direction. A plastic working method of a gear or a gear-like object, characterized in that the opening end is enlarged when the gear or the gear-like object is ejected from the die hole when it is filled. 2. The method for plastically working a gear or a gear-like object according to claim 1, wherein the elastic contraction deformation is caused by an inclined surface inclined with respect to a punch moving direction of a taper member provided on the punch side. A plastic working method of a gear or a gear-like object, which is produced by applying a pressing force in an inner circumferential direction to a pressure receiving portion provided on the outer periphery of the opening end of the die hole. 3. The method of plastic working a gear or a gear-like object according to claim 1, wherein the elastic contraction deformation is caused by a pressing member provided on the punch side, around an outer side of an opening end of the die hole. A method of plastic working a gear or a gear-like material, which is produced by pressurizing a fluid member inside a groove formed in the groove. 4. The method of plastic working a gear or a gear-like object according to claim 1, wherein the elastic contraction deformation is a pressure receiving member arranged closer to the counter punch than the die member is. A plastic working method of a gear or a gear-like object, which is produced by warping and deforming the die member which receives a pressing force from the punch while supporting the die. 5. The method of plastic working a gear or gear-like article according to claim 1, wherein the material is a container provided on the punch side when the punch moves to the die member side. A plastic working method of a gear or a gear-like object, characterized in that the material enters the inside of a member and in this state the material is compressed by the punch and the counter punch.