JP2001269745A - Gear shaping method, and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the productivity of the gear by significantly shortening the manufacturing time of a gear and remarkably improving the operational efficiency of a gear shaping device. SOLUTION: The gear shaping apparatus 10 for forging and forming a gear stock 12 has a fixed die 58 with a fixed gear cutting portion 82 formed thereon, and a movable die 96 with a movable gear cutting portion 112 formed thereon. A portion 114 is demarcated by the fixed gear cutting portion 82 and the movable gear cutting portion 112. The gear stock 12 is pressed by a punch 106 downwardly in the perpendicular direction, and the material of the gear stock 12 is allowed to flow in the tooth gear cutting 114 to form a tooth profile portion 118 of a gear 116. The fixed gear cutting portion 82 and the movable gear cutting portion 112 are joined with each other in an a state orthogonal to the perpendicular direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear forming method and apparatus for forming gears by hot forging or cold forging.

[0002]

2. Description of the Related Art In a conventional gear forming apparatus, for example,
BACKGROUND ART When a gear used for a transmission of an automobile is formed by hot forging or cold forging, the gear is formed through a plurality of manufacturing steps.

FIGS. 9A and 9B schematically show a gear forming process of a gear forming apparatus according to the prior art. First, as a first step, as shown in FIG. 9A, a gear blank 4 is placed on a mold 1 on which a tooth forming section 2 having a substantially triangular tip 3 is formed.
Then, the gear blank 4 is pressed vertically downward by a punch, and the gear blank 4 is caused to flow into the tooth forming section 2. Thereafter, the gear blank 4 whose one end is formed in a substantially triangular shape is released from the mold 1.

Next, as a second step, as shown in FIG. 9B, the other end of the gear blank 4 is divided into a tapered portion 7 and a linear portion 8.
Are housed in the mold 5 on which the tooth forming part 6 is formed. Thereafter, the gear blank 4 is pressed vertically downward by a punch, and the gear blank 4 is caused to flow into the tooth forming section 6 to form a tooth profile 9.

[0005]

However, the gear forming apparatus requires a plurality of manufacturing steps such as inverting the gear material as described above before the gear is formed, so that it takes a long time to manufacture the gear. Problems have been pointed out that the work is complicated and the cost increases. Furthermore, in order to arrange different types of dies, it is necessary to install a plurality of molding devices, which leads to an increase in equipment costs and an increase in installation space, and it has become difficult to operate the devices themselves efficiently. .

SUMMARY OF THE INVENTION The present invention has been made in view of such problems, and a gear is formed in a single manufacturing process by arranging a mold having a tooth-forming portion adapted to the shape of the gear. Reduce the production time of gears, reduce equipment costs and installation space, improve the operation efficiency of molding equipment, and reduce the production cost of molded products. It is an object of the present invention to provide a gear forming method and an apparatus therefor.

[0007]

SUMMARY OF THE INVENTION The present invention is directed to a method of forming a gear having a first mold, a second mold, and a punch facing one of the first and second molds. A gear material is stored between a first tooth forming part formed on the first mold and a second tooth forming part formed on the second mold, The end of the first tooth-forming part of the mold and the end of the second tooth-forming part of the second mold are joined so as to be perpendicular to the vertical direction, and the gear blank is formed by the punch. By pressing, the gear material is caused to flow simultaneously into the first tooth-forming portion and into the second tooth-forming portion to form the tooth portion of the gear by a single punching action.

Further, the present invention has a first mold and a second mold, wherein a first tooth forming portion formed on the first mold and the second mold are provided. And a second tooth-forming part for forming a tooth-shaped part of the gear is defined by the second tooth-forming part, the tooth-forming part having an end of the first tooth-forming part and the second tooth-forming part. It has a joint surface orthogonal to the vertical direction at the end of the tooth forming portion.

Further, the first tooth forming portion has a pair of opposed chamfer portions formed in a substantially triangular shape, and an undercut whose one main surface is inclined at a predetermined angle in a direction away from the axial direction. Part, and a linear part whose one main surface is parallel to the axial direction. The second tooth forming part has a tapered part and a top surface inclined at a predetermined angle in a direction away from the axial direction. A first straight portion, and a second straight portion inclined at a predetermined angle in a direction approaching the first straight portion in the axial direction, and an upper end of the straight portion and a lower end of the tapered portion are in a vertical direction. It is good to join orthogonally.

As described above, according to the present invention, the tooth forming part for forming the gear tooth part is formed by the first tooth forming part and the second die formed in the first mold. Second formed
And the first mold and the second mold are arranged in a single molding device, so that the gear is forged in a single manufacturing process. Can be
The gear manufacturing time can be significantly reduced. In addition, since it is not necessary to install a plurality of molding devices in which different types of dies are arranged in order to form gears, it is possible to reduce equipment costs and installation space, and dramatically improve the operation efficiency of the device itself. Thus, the manufacturing cost of the molded product can be reduced.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a gear forming method according to the present invention will be described below in detail with reference to FIGS. The use of the gear forming apparatus is not limited, but is preferably used, for example, for manufacturing a transmission gear for an automobile.

The gear forming apparatus 10 according to the present embodiment
This is for forging an annular gear blank 12 (see FIG. 8A). As shown in FIG. 1, an annular first lower mount 14 and the first lower mount 14 are fixed on the first lower mount 14. An annular second lower mount 16 having a smaller diameter than the first lower mount 14, an annular first upper mount 18 located above the first lower mount 14 and the second lower mount 16, An annular second upper mount 20 fixed to the bottom surface side of the first upper mount 18 and having a smaller diameter than the first upper mount 18; and the first and second lower mounts 14 and 16
And a fixing portion 22 and a punch portion 24 provided between the first and second upper mounts 18 and 20. A plurality of guide holders 26 are fixed to the bottom surface of the second upper gantry 20 at equal angles about the axis of the second upper gantry 20. The guide holder 26 is provided with a tip 28 having a smaller diameter. A plurality of guides 30 are erected between the distal end portion 28 of each of the guide holders 26 and the second lower frame 16, and each of the guides 30 has the second
A coil spring 32 seated on the upper surface of the lower gantry 16 and the tip portion 28 is wound.

The first lower mount 14 and the second lower mount 16 are provided substantially at the center of the first lower mount 14 and the second lower mount 16.
A hole 34 communicating with the lower frame 16 is formed. A large-diameter first opening 36 is formed substantially at the center of the first upper mount 18, and similarly, the second upper mount 20
Communicates with the first opening 36 at a substantially central portion thereof.
A second opening 38 having a smaller diameter than the opening 36 is formed. The first opening 36 and the second opening 38
Inside, there are claw portions 18a and 20a protruding inward, respectively.
Are formed, and the protruding length of the claw portion 18a is shorter than that of the claw portion 20a.

The fixed portion 22 is fitted in a first concave portion 40 formed at a substantially central portion of the second lower frame 16 and has an annular base 42 having an opening 43 formed at a substantially central portion; The base 4
The first plate 44 has a substantially cylindrical punch guide 46 erected at a substantially central portion of an upper end surface of the first plate 44. A second plate 48 and a first ring 50 are externally provided on the first plate 44 side of the punch guide 46, and a knockout punch 52 externally fitted to the punch guide 46 is provided on the first ring 50. It is fixed. 1, the lower part of the knockout punch 52 is formed as a thick part 52b, and the upper part is a thin part 52b via a taper part.
a is formed.

Further, a sleeve 54 is fixed on the first plate 44 so as to be attached to the second plate 48, and the knockout punch 5 is mounted on the sleeve 54.
A spacer 56 and a fixed mold 58 that fits over the spacer 56 are provided so as to surround the spacer 2. A space 55 is formed between the knockout punch 52 and the sleeve 54 so as to surround the knockout punch 52. An annular mounting portion 60 is formed on the first plate 44, and a second ring 62 for centering the first plate 44 and the sleeve 54 is provided on the first plate 44 and the sleeve 54. 54 is fitted to the outer peripheral surface. The second ring 62 is held on the mounting portion 60 of the first plate 44.

Claw portions 58a are provided on the outer peripheral surface of the fixed mold 58.
Is formed, and the claw portion 58a of the holder 64 is formed on the claw portion 58a.
The engagement of the base 4a pushes the base 42, the first plate 44, the second plate 48, the sleeve 54, the spacer 56, and the fixed mold 58 vertically downward. That is, the base 42 and the second
The outer side of the ring 62 and the holder 64 is provided in a first concave portion 66 formed in the second lower frame 16.
And a screw formed on the inner periphery of the second holding member 70 is screwed with a screw engraved on the outer periphery of the upper end portion of the first holding member 68, and the second holding member Bent part 7 of material 70
Since the second holding member 2 is engaged with the holder 64, the second holding member 70 is screwed into the holder 64, the fixed mold 58, the sleeve 54, the first plate 44, and the base. 42 is pressed vertically downward.

Further, on the bottom surface of the first ring 50, the first plate 44 and the second plate 4
8, a knockout pin 74 is fixed.
The knockout pin 74 extends downward in FIG. 1 through the opening 43 formed in the base 42 and into the hole 34 communicating with the first and second lower frames 14 and 16. It is connected to the piston rod 76 of the inserted hydraulic piston for fixed part.

Therefore, the knockout pin 74 is configured to be vertically movable in the axial direction by the piston rod 76 of the fixed portion hydraulic piston which is displaced under the action of the fixed portion hydraulic mechanism (not shown). The knockout punch 52 is slidable in the axial direction on the outer peripheral surface of the punch guide 46 in conjunction with the knockout pin 74.

On the other hand, as shown in FIG.
A cavity 78 that circulates between the mold and the fixed mold 58 is formed. As will be described later, the cavity 78 serves as a flow space in which the meat of the gear material 12 flows when the gear material 12 is pressed from above.

Further, as shown in FIGS. 2 and 3, the stationary mold 58 has a material placing portion 80 formed in a substantially flat shape for placing the gear material 12 thereon. The inclined chamfer portions 81 facing each other so as to be formed in a substantially triangular shape using the step portion 83 on the outer periphery of the placing portion 80
a, 81a, an undercut portion 81b whose one main surface is inclined at a predetermined angle in a direction away from the axial direction of the punch guide 46, and a straight line whose one main surface is parallel to the axial direction of the punch guide 46. Fixed tooth forming portion 82 comprising a portion 81c
Are formed. In this case, the chamfer portion 81a and the straight portion 81
c is terminated.

As shown in FIG. 1, the punch section 24 has a cylindrical first holder 84 and a second holder 86 which is provided at the upper end of the first holder 84. A protrusion 88 formed so as to protrude inside the second holder 86 abuts on the upper end surface of the first holder 84. The lower end surface of the second holder 86 is provided with a stop ring 9 which is engaged with a first claw portion 84a formed on the outer peripheral surface of the first holder 84.
0 is fitted, and the projection 88 and the retaining ring 90
By holding the holder 84, the first holder 8
4 and the second holder 86 are fixed. That is, the second stop ring 90 is locked vertically.
A screw formed inside the support ring 92 is screwed with a screw on the outer periphery of the holder 86. A bent portion 94 protruding outward is formed at an upper end portion of the second holder 86 in FIG. 1, and the bent portion 94 engages with a claw portion 20 a formed on the second upper frame 20. . The first holder 84
The second claw portion 84b formed on the inner peripheral surface of the
An annular movable mold 96 having a fixed shape is fixed, and a spacer 100 is fitted into the concave portion 98. Of course, the movable mold 96 is disposed so as to face the fixed mold 58.

A first pressing plate 102a is fixed to the upper surface of the movable mold 96 and the spacer 100 so as to include a fixing surface between the movable mold 96 and the spacer 100, and the first pressing plate 102a A second pressing plate 102b is fixed on the protrusion 88 formed on the second holder 86. Further, the second pressing plate 102b and the second pressing plate 102b are formed so as to include a fixing surface between the second pressing plate 102b and the second holder 86.
A third pressing plate 102c is fixed on the holder 86, and the third pressing plate 102c is engaged with a claw 18a formed on the first upper base 18. The first to third pressing plates 102a to 102c
Has a larger diameter in the order of the first to third pressing plates 102a to 102c.

The movable mold 96, the spacer 100, and the first to third pressing plates 102a to 102a
A rod 104 extending vertically downward penetrates substantially the center of each of the rods 02c. This rod 104
It is formed in a substantially columnar shape whose diameter decreases in four steps as it goes downward. A punch 106 is fixed to one end of the rod 104, and the other end is connected to a hydraulic mechanism (not shown) for a movable part. It can move up and down freely. Therefore, the punch 106 can also move vertically in the axial direction.

Note that, like the rod 104, the third pressing plate 102c is also connected to the movable portion hydraulic mechanism. Accordingly, the first to third pressing plates 1 fixed to each other under the operation of the movable portion hydraulic mechanism
02a to 102c are vertically movable in the axial direction. Along with this, the movable mold 96 fixed to the first pressing plate 102a can also move up and down in the axial direction, and can approach or separate from the fixed mold 58.

As shown in FIGS. 2 and 3, the movable mold 96 has a tapered portion 108 and a first surface whose upper surface is inclined at a predetermined angle in a direction away from the axial direction of the punch guide 46.
And a second linear portion 110b whose upper surface is inclined a predetermined angle abruptly in a direction approaching the axial direction of the punch guide 46 from the first linear portion 110a. Have.

The tapered portion 10 of the movable tooth forming portion 112
8 and the upper end of the straight portion 81c of the fixed tooth forming portion 82 formed in the fixed mold 58 are joined in a direction perpendicular to the vertical direction (a direction orthogonal to the axial direction of the punch guide 46). Defines a tooth forming profile 114 that forms the tooth profile 118 of the gear 116 (see FIG. 8B).

The gear forming apparatus 10 according to the present embodiment
Basically, the configuration is as described above. Next, the operation and effects will be described.

First, the punch 106 and the movable mold 96 are separated from the fixed mold 58 under the action of the movable section hydraulic mechanism (not shown), as shown in FIG. Then, the gear material 12 is placed on the material placing portion 80 formed on the stationary mold 58. Thereafter, the movable mold 96 is moved vertically downward under the action of the movable portion hydraulic mechanism,
The movable mold 96 is brought into close contact with the fixed mold 58 (see FIG. 5).

Next, similarly, the rod 104 is moved vertically downward under the action of the hydraulic mechanism for the movable part. As a result, the punch 106 is displaced vertically downward, and the upper surface of the gear blank 12 is pressed vertically downward by the punch 106 (see FIG. 6). At this time, the pressing speed of the punch 106 pressing the gear blank 12 is set to a predetermined speed in advance.

The flesh of the gear blank 12 pressed vertically downward by the punch 106 is the tooth forming section 11 defined by the fixed tooth forming section 82 and the movable tooth forming section 112.
4, and the tooth profile 118 of the gear 116 is formed (see FIGS. 6 and 8B). At the same time, the meat of the gear material 12 flows into the cavity 78 formed between the punch guide 46 and the fixed mold 58 and circulating around the punch guide 46.

Thereafter, the rod 104 is moved vertically upward under the action of the hydraulic mechanism (not shown) for the movable part. As a result, the punch 106 is displaced vertically upward, and the punch 106
Separated from 8. Similarly, the movable mold 96 is moved vertically upward under the action of the hydraulic mechanism for the movable section to be separated from the fixed mold 58 (see FIG. 7).

With the movable mold 96 and the punch 106 separated from the fixed mold 58, a hydraulic mechanism (not shown) for the fixed part is operated. The piston rod 7 of the hydraulic piston for the fixed part is operated under the action of the hydraulic mechanism for the fixed part.
6 moves vertically upward, and accordingly, the knockout punch 52 fixed to the first ring 50 via the knockout pin 74 slides vertically on the outer peripheral surface of the punch guide 46. As shown in FIG. 7, the knockout punch 52 slid vertically upward comes into contact with the gear 116 and separates the gear 116 from the material placing portion 80 formed on the fixed mold 58. Then, the gear 116
Is transported to the next step by a transport device (not shown),
Finally, machining is performed to a predetermined size and shape to complete the product.

Here, in the present embodiment, the straight portion 81c of the fixed tooth forming portion 82 formed in the fixed mold 58 is used.
And the movable tooth forming part 1 formed on the movable mold 96
The tooth forming portion 114 for forming the tooth portion 118 of the gear 116 is defined by joining the lower end of the twelve tapered portions 108 at right angles to the vertical direction. In addition, since the fixed mold 58 and the movable mold 96 are arranged in one gear forming device 10, when the gear material 12 is forged by the gear forming device 10, a single punching operation is required. The tooth profile 118 of the gear 116 can be formed. That is, the gear 116 can be forged from the gear blank 12 in one manufacturing process.

[0034]

As described above, according to the present invention,
A tooth forming part for forming a tooth part of a gear is defined by a fixed tooth forming part formed in a fixed mold and a movable tooth forming part formed in a movable mold, and the fixed mold and the movable tooth are formed. Since the mold and the mold are arranged in one forming apparatus, the gear can be forged in one manufacturing process, and the manufacturing time of the gear can be significantly reduced. In addition, since it is not necessary to install a plurality of molding apparatuses in which different types of dies are arranged for molding gears as in the prior art, it is possible to reduce equipment costs and installation space. The unique effect that the operational efficiency of the device itself is dramatically improved and the manufacturing cost of the molded product can be reduced.

[Brief description of the drawings]

FIG. 1 is a partially omitted longitudinal sectional view showing a gear forming apparatus according to an embodiment.

FIG. 2 is a partially omitted enlarged longitudinal sectional view showing a tooth forming portion in the gear forming apparatus of FIG. 1;

FIG. 3 is a partially omitted enlarged perspective explanatory view showing the tooth forming portion of FIG. 2;

FIG. 4 is a partially omitted enlarged longitudinal sectional view showing a state in which a punch portion is separated from a fixed portion in the gear forming device of FIG.

FIG. 5 is a partially omitted enlarged longitudinal sectional view showing a state where a movable mold is in contact with a fixed mold in the gear forming apparatus of FIG. 1;

FIG. 6 is a partially omitted enlarged longitudinal sectional view showing a state immediately after a gear material is pressed by a punch in the gear forming apparatus of FIG. 1;

FIG. 7 is a partially omitted enlarged longitudinal sectional view showing a state in which the gear after forging has been released from the fixed mold in the gear forming apparatus of FIG. 1;

FIG. 8A is a perspective view showing a gear material, and FIG.
FIG. 3 is a perspective view showing the gear after forging.

FIG. 9A and FIG. 9B are schematic operation explanatory views of a conventional gear forming apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Gear forming apparatus 12 ... Gear material 58 ... Fixed die 81a ... Chamfer part 81b ... Undercut part 81c ... Linear part 82 ... Fixed tooth forming part 96 ... Movable die 106 ... Punch 108 ... Taper part 110a ... First Linear portion 110b Second linear portion 112 Movable tooth forming portion 114 Gear forming portion 116 Gear 118 Gear portion

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Seichi Akimoto 8-1 Honcho, Wako-shi, Saitama F-term in Honda Motor Co., Ltd. Wako Factory (Reference) 4E087 AA10 CA14 CA22 CA33 CB01 CB03 EC13 EC18 EE02 HA05

Claims (3)

[Claims] 1. A gear forming method comprising: a first mold, a second mold, and a punch facing one of the first and second molds, wherein the first mold is provided. A gear material is housed between a first tooth forming part formed in a mold and a second tooth forming part formed in the second mold, and a first tooth forming part of the first mold is stored. The end of the part and the end of the second tooth forming part of the second mold are joined so as to be orthogonal to the vertical direction, and the gear material is pressed by pressing the gear material with the punch. And simultaneously flowing the first and second tooth-forming portions into the first and second tooth-forming portions to form the tooth portion of the gear by a single punching operation. 2. A mold having a first mold and a second mold, wherein a first tooth forming portion formed on the first mold and a second mold formed on the second mold. A tooth shaping portion for shaping the tooth shape of the gear is defined by the second tooth shaping portion, and the tooth shaping portion includes an end of the first tooth shaping portion and a second tooth shaping portion. A gear forming device having a joint surface orthogonal to a vertical direction at an end portion. 3. The gear forming device according to claim 2, wherein the first tooth forming portion is formed in a substantially triangular shape with a pair of opposing chamfer portions in a direction away from the axial direction. The main surface comprises an undercut portion inclined at a predetermined angle, and a straight portion having one main surface parallel to the axial direction. The second tooth forming portion is separated from the tapered portion in the axial direction. A first linear portion whose upper surface is inclined at a predetermined angle in the direction, and a second linear portion inclined at a predetermined angle in a direction approaching the axial direction from the first linear portion, and an upper end of the linear portion A lower end of the tapered portion and a lower end of the tapered portion are joined at right angles to a vertical direction.