JPH0847743A - Forming device for clutch tooth for transmission gear - Google Patents

Abstract

PURPOSE:To simplify the structure, to reduce the number of parts and the cost, and to facilitate the assembly and the maintenance. CONSTITUTION:A die hole 33a formed on a tapered cam surface where the inner circumferential surface of an upper part is contracted downward is provided on a die main body 16, a movable receiving piece 36 is fitted to the lower part of the die hole in a vertically movable manner, and a number of die pieces 40 where a plurality of forming teeth whose thickness is increased upward are formed on an inner end part in the circumferential direction are provided, each die piece is radially arranged on an outer circumferential part of the movable receiving piece, and the outer circumferential surface of each die piece is abutted on a cam surface 33b of the die hole. An intermediate product having a number of primary clutch teeth which extend in the vertical direction on the outer circumference of the lower part of a boss part and formed in the circumferential direction at the prescribed pitch is provided, the intermediate product is loaded on the upper part of each die piece, and a punch 50 is provided where each primary clutch tooth is engaged with the forming tooth of the die piece, and each die piece is pressed downward together with the intermediate product.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speed change gear having spline tooth-shaped clutch teeth integrally formed on an outer periphery of a boss portion,
In particular, the present invention relates to a clutch tooth forming apparatus for forming the clutch teeth in a reverse taper shape in which the tooth thickness at the root portion is smaller than the tooth thickness at the shaft end portion.

[0002]

2. Description of the Related Art As a conventional technique, Japanese Patent Laid-Open No. 63-120
There was one described in Japanese Patent No. 958, that is, one shown in FIGS. 14 and 15. In FIG. 14, reference numeral 1 denotes a lower die mounting base, and the lower die 2 and the cylindrical case 3 are concentrically arranged on the upper surface of the mounting base 1 on the axial center portion and the outer peripheral portion, and fixed by bolting. An annular flange 4 is fitted between the two and the cylindrical case 3 so as to be vertically movable, and is urged upward by a spring 5.

The lower die 2 has a large number of die fitting insertion holes 2a, each having a circular cross section and a flat upper surface, formed in its upper surface in a radial direction. Each die fitting insertion hole 2a has a round bar-shaped upper surface. The die 6 cut in a flat shape is fitted so as to be slidable in the radial direction. The die 6 has a molding tooth 6a whose tooth thickness increases upward at the inner end on the axial center side, and a slope inclined inward toward the outer end and a pin hole parallel to this. (Both of which are omitted from the reference numeral).

Further, the case 3 integrally has a die presser 3a bent in the axial direction at the upper end thereof, and the die presser 3a presses down the die 6 to restrict the rotation of the die 6. Vertical cam fitting holes 7 are formed at a predetermined pitch in the circumferential direction on the outer peripheral portion of the die holder 3a of the case 3.
The cams 8 are slidably fitted into the cam fitting holes 7 and fixed to the flange 4 by bolts.

Each of the cams 8 has an upper end projecting slightly upward from the case 3, and a pin 9 is tilted inwardly and fixed upright inside the lower part, and the pin 9 is provided on the inner side surface facing the pin 9. To form a cam surface 8a having an inclination angle equal to.
Then, the outer end portion of the die 6 described above is projected into the cam fitting insertion hole 7 so that the pin hole is slidably fitted into the pin 9 and the inclined surface of the outer peripheral end of the die 6 is cam surface 8a. Abut.

Further, the intermediate product 10 is placed on the axial center of the lower mold 2 described above. As shown in FIG. 16, this intermediate product 10 has primary clutch teeth 11 of a spline tooth shape extending downward with an equal tooth thickness on the outer periphery of a boss portion whose lower portion is formed to have a small diameter. 11 is engaged with the molding tooth 6a of each die 6 described above. Then, the intermediate product 10 is pressed by the upper mold 12, the respective cams 8 are pressed downward by the upper mold mounting base (punch) 13, and the respective dies 6 are moved in the axial direction by the cam surface 8a.
The primary clutch teeth 11a are pressed in the axial direction by the molding teeth 6a of each die 6, and as shown in FIG.
The reversely tapered clutch teeth 11 are formed such that their tooth thickness is smaller than the tooth thickness of the shaft end (lower part).

[0007]

In the prior art, the lower die 2 is formed with radial die-insertion holes 2a whose upper surface is cut, and a rod-shaped die 6 is formed in the die-insertion holes 2a. It can be slidably inserted, or the case 3 can be formed with the same number of cam fitting holes 7 as the die 6 at a predetermined pitch in the circumferential direction, and piece cams 8 can be individually provided in the respective cam fitting holes 7. Since they were mated, the structure became complicated and the number of parts increased,
There are drawbacks that the manufacturing cost is high and the assembly is troublesome. SUMMARY OF THE INVENTION It is an object of the present invention to provide a novel transmission gear clutch tooth forming apparatus that solves the above-mentioned drawbacks.

[0008]

The present invention is configured as follows to achieve the above object. That is, the die main body is provided with a die hole formed in a taper-shaped cam surface whose inner peripheral surface shrinks downward, and a movable receiver is vertically movably fitted to the lower part of the die hole. A large number of die pieces each having a plurality of molding teeth formed in the circumferential direction, the tooth thickness of which increases toward the top, are provided at the end portions, and the die pieces are radially arranged on the outer peripheral portion of the movable support, and The outer peripheral surface is brought into contact with the cam surface of the die hole, an intermediate product having a large number of primary clutch teeth extending vertically and formed at a predetermined pitch in the circumferential direction is provided on the lower outer periphery of the boss portion, and each intermediate product is The punch is mounted on the upper part of the die piece, each primary clutch tooth is meshed with the molding tooth of the die piece, and a punch is provided to push and move the die piece together with the intermediate product downward. In this case, it is preferable that the die piece is formed in a fan shape in a plan view, which becomes wider from the inner peripheral side toward the outer peripheral side, and the circumferentially opposite end surfaces of the die pieces adjacent to each other in the circumferential direction are close to each other. Also, while forming a slit extending in the radial direction on the inner peripheral portion of the die piece,
It is preferable that the slits divide each molded tooth adjacent in the circumferential direction in the circumferential direction. Further, it is preferable that a conical positioning hole is formed on the lower surface of the die piece, and an engaging body that is biased upward by an elastic body to engage with the positioning hole is provided on the movable support.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. In the drawings, FIG. 1 is a sectional view of a molding apparatus for molding an intermediate product according to the present invention. In FIG. 1, reference numeral 15 denotes a primary molding device, which fits and holds a lower mold 17 on an upper part of a mold main body 16, mounts an intermediate product 25 on the lower mold 17, and mounts the mounted intermediate product 25. The punch 20 applies pressure toward the lower die 17 to form a predetermined shape.

That is, the lower die 17 is formed with a spline tooth-shaped primary forming tooth 18 having an equal tooth thickness in the vertical direction on the inner peripheral portion thereof, and an annular drawing protrusion 19 is formed on the inner peripheral side of the primary forming tooth 18.
And the punch 20 has a first inner peripheral side.
The punch 21 and the punch 22 on the outer peripheral side are fixed to the ram side, and an annular diaphragm protrusion 21a facing the diaphragm protrusion 19 is formed on the outer periphery of the lower end of the die 1 punch 21. Further, the intermediate product 25 has a rim portion 25a for gear tooth molding formed on the outer periphery thereof, and a spline tooth-shaped primary clutch tooth 26 formed on one (lower) outer peripheral surface of the boss portion 25b on the inner peripheral side.

Then, the intermediate product 25 is placed on the lower mold 17, the primary clutch teeth 26 are engaged with the primary molding teeth 18, and the punch 20 is moved downward to direct the intermediate product 25 toward the lower mold 17. And pressurizing the inner peripheral surface of the boss portion 25b of the intermediate product 25 with the squeezing projections 19 and 21a to cause plastic flow in the outer peripheral direction, that is, in the direction of the primary molding teeth 18, as shown in FIGS. First, the primary clutch teeth 26 are finished into a highly accurate spline tooth profile having a constant tooth thickness from the base of the boss portion 25b toward the lower end. In addition,
23 is an intermediate product 25 obtained by finishing the primary clutch teeth 26.
Is an extruding pin that pushes upward from the lower mold 17.

In FIG. 4, reference numeral 30 denotes a clutch tooth forming apparatus for forming the primary clutch teeth 26 in a reverse taper shape in which the tooth thickness at the root (upper end) portion is smaller than the tooth thickness at the shaft end (lower end) portion. Yes, it is as follows. That is, 31 is a mold main body, and this mold main body 31 is a cam cylinder 3 reinforced by a clamp 34 on the upper part of a cylindrical holding ring 32.
3 is fixed coaxially, and the cam cylinder 33 forms the die hole 33a. The die hole 33a is formed with a tapered cam surface 33b whose inner peripheral surface is contracted downward.
The cam cylinder 33 is integrally press-fitted and fixed to the clamp 34,
The clamp 34 is detachably fixed to the holding ring 32 by a connecting tool (not shown).

The lower portion of the retaining ring 32 is closed by a deposit (not shown), and an elastic body 35 such as rubber and a movable support 36 are sequentially stacked on the upper portion of the deposit, and the movable support 36 is inserted through the elastic body 35. Are vertically movably fitted to each other, and an annular positioning ring 39 is fixed to the outer peripheral portion of the upper portion of the movable support 36. This positioning ring 39 consists of a ball 3
The engaging bodies 37 of 9 are fitted, and each engaging body 37 is urged upward by the spring 38. The engagement body 37 may have a pin-shaped upper end formed into a conical surface or a hemispherical surface so as to urge it upward. The positioning ring 39 restricts downward movement by the stopper balls 23 provided at three positions in the circumferential direction of the lower end portion of the cam barrel 33. As a result, the positioning ring 39, the die piece 40, which will be described later, the cam cylinder 33, and the clamp 34 are detachably attached to the holding ring 32 as a unit.

A large number of die pieces 40 are radially arranged and placed on the upper surface of the positioning ring 39. Each of the die pieces 40 has the same structure, and one of them will be described with reference to FIGS. 5 to 7. The main body 40a of the die piece 40 is formed in a fan shape in plan view which becomes wider from the inner peripheral side to the outer peripheral side (see FIG. 6, FIG. 7) so that both circumferential end faces of the die pieces 40 adjacent to each other in the circumferential direction are brought close to each other. Further, two molding teeth 41 are formed at the inner end portion of the die piece main body 40a in the circumferential direction so that the tooth thickness becomes thicker in the upward direction, and the outer peripheral surface is formed in an inclined surface 42 that inclines inwardly in the upward direction. To do. Further, a slit 43 extending in the radial direction (left-right direction) is formed on the inner peripheral portion,
Forming teeth 41 adjacent to each other in the circumferential direction by the slit 43,
41 is divided in the circumferential direction. Reference numeral 44 denotes a dispersion hole formed at the inner end of the slit 43 to disperse the stress concentration. Further, a conical positioning hole 45 is formed in the center of the lower surface of the die piece main body 40a.
Further, an arc-shaped groove 47 centered on the axial center of the cam barrel 33 is formed in the middle portion of the lower portion of the die piece main body 40a in the inner / outer (left / right) direction.

The die dies 40 are arranged in a radial manner on the upper surface of the placement ring 39 described above, and a ring-shaped spring 48 made of a spring steel wire is fitted into the groove 47 to fit the die dies 40. The beveled surface 42 at the outer peripheral end of the die is brought into contact with the cam surface 33b of the die hole 33a, and the positioning hole 45 formed on the lower surface of each die piece 40 is fitted into the engagement body 37 on the side of the positioning ring 39, and the upper end of the clamp 34 is The stopper ring 46 screwed into the above restricts the die pieces 40 from moving upward. Then, the intermediate product 2 molded by the primary molding device 15
5-1 is placed on the upper part of each die piece 40, and each primary clutch tooth 26 is attached to the molding tooth 41 of each die piece 40.
The intermediate product 25-1 with the punch 50.
Each die piece 40 is pressed and moved via.

Then, each die piece 40 is moved in the axial direction by the cam surface 33b, and its molding tooth 41 presses each primary clutch tooth 26 in the axial direction, as shown in FIGS. 8 and 9. The reverse tapered clutch teeth 27 are formed so that the tooth thickness at the root portion (upper portion) is smaller than the tooth thickness at the shaft end portion (lower portion). In this case, each die piece 40 integrally has two molding teeth 41, 41 on the inner peripheral portion as shown in FIG. 6, but these molding teeth 41, 41 are slits on the inner peripheral portion. Four
By separating them by means of 3, it becomes possible to move them slightly toward and away from each other in the circumferential direction, and the primary clutch teeth 26 can be smoothly pressure-molded. Further, when the molded intermediate product 25-1 is released upward by the extrusion pin 49, each die piece 4
When the molding tooth 41 of 0 receives an upward load, each die piece 4
0 rotates slightly upward about the stopper ring 46, and the molded clutch teeth 27 are smoothly disengaged from the molding teeth 41 of each die piece 40.

FIG. 10 shows a second embodiment of the clutch tooth forming apparatus. In this product, a punch 50 is formed by a first punch 51 on the inner circumference side and a second punch 52 on the outer circumference side. The first punch 51 is lowered by a spring 53 at the center of a pressure plate 54 fixed to a ram. Then, the second punch 52 is made cylindrical and is fixed to the outer peripheral portion of the pressure plate 54. Then, the intermediate product 25-1 molded by the primary molding device 15 is pressed downward by the first punch 51, and each die piece 40 is pressed downward by the second punch 52.

The die pieces 40 are shown in FIGS.
As shown in FIG. 5, a slit 43 that divides each of the molding teeth 41, 41 in the circumferential direction is formed at the inner end (left end) of the main body 40a, and a dispersion hole 44 is formed from the slit 43 to the outer peripheral side (right side). ) Are formed so as to be spaced apart from each other, and cracks generated in the outer peripheral direction from the slits 43 due to the load at the time of molding are dispersed in the dispersion holes 4
4 is different from the above-described first embodiment in that it is regulated by No. 4, but otherwise the structure is substantially the same as in the first embodiment. The number of forming teeth 41 formed on the die piece 40 is appropriately increased or decreased depending on the number of teeth, the diameter of the clutch teeth 27, the module, and the like.

[0019]

As is apparent from the above description, according to the present invention, a plurality of molding teeth are circumferentially formed on the inner end portion of the die piece, and the die pieces are radially arranged and mounted on the movable support. Since the outer peripheral surface is brought into contact with the tapered cam surface of the die hole, the structure is simplified, the number of parts is reduced, the cost is low, and the assembly and maintenance inspection are expensive. .

[Brief description of drawings]

1 is a sectional view of a molding apparatus for molding an intermediate product according to the present invention.

FIG. 2 is a sectional view of an essential part of an intermediate product.

FIG. 3 is a view shown in FIG. 2A.

FIG. 4 is a cross-sectional view of the clutch tooth forming apparatus according to the first embodiment of the present invention.

FIG. 5 is a sectional side view of the die piece showing the first embodiment of the present invention.

FIG. 6 is a plan view of FIG.

FIG. 7 is a bottom view of FIG.

FIG. 8 is a cross-sectional view of essential parts of a molded product in which clutch teeth are molded.

9 is a view shown in B of FIG. 8. FIG.

FIG. 10 is a sectional view of an essential part of a clutch tooth forming apparatus showing a second embodiment of the present invention.

FIG. 11 is a sectional side view of a die piece showing a second embodiment of the present invention.

FIG. 12 is a plan view of FIG. 11.

FIG. 13 is a bottom view of FIG. 11.

FIG. 14 is a sectional view of a conventional clutch tooth forming apparatus.

15 is a plan view of the die fitting hole portion of FIG. 14. FIG.

FIG. 16 is a sectional view of a conventional intermediate product.

FIG. 17 is a cross-sectional view of a conventional molded product in which clutch teeth are molded.

[Explanation of symbols]

 15 Primary Molding Equipment 16 Main Mold 17 Lower Mold 18 Primary Molding Teeth 19 Drawing Protrusion 20 Punch 21 First Punch 22 Second Punch 25, 25-1 Intermediate Product 25a Rim 25b Boss 26 Primary Clutch Teeth 27 Clutch Teeth 30 Molding Device 31 Main mold 32 Holding ring 33 Cam tube 33a Die hole 33b Cam surface 34 Tightening 35 Elastic body 36 Movable receiving plate 37 Engaging body 38 Spring 39 Positioning ring 40 Die piece 41 Forming tooth 42 Slope 43 Slit 44 Stress dispersion hole 45 Positioning hole 46 Stopper ring 47 Groove 48 Spring 49 Push pin 50 Punch 51 First punch 52 Second punch 53 Spring 54 Pressure plate

Claims (4)

[Claims] 1. A die main body is provided with a die hole formed in a taper-shaped cam surface whose inner peripheral surface is reduced downward, and a movable receiver is vertically movably fitted to the lower part of the die hole. A plurality of die teeth each having a plurality of molding teeth formed in the circumferential direction at the inner end portion, the tooth thickness of which increases toward the top, and each die piece is radially arranged on the outer periphery of the movable support,
The outer peripheral surface of each die piece is brought into contact with the cam surface of the die hole, and an intermediate product having a large number of primary clutch teeth extending vertically and formed at a predetermined pitch in the circumferential direction is provided on the lower outer periphery of the boss portion, and the intermediate product Place the product on top of each die piece,
Engage each primary clutch tooth with the molding tooth of the die piece,
A device for forming clutch teeth for a transmission gear, comprising a punch for pressing and moving each die piece together with an intermediate product. 2. The die piece is formed in a fan shape in a plan view, which becomes wider from the inner peripheral side toward the outer peripheral side, and the circumferentially opposite end surfaces of the die pieces adjacent to each other in the circumferential direction are brought close to each other. The apparatus for forming clutch teeth for a transmission gear according to claim 1. 3. The die according to claim 1, wherein a slit extending in the radial direction is formed in the inner peripheral portion of the die piece, and each of the molding teeth adjacent in the circumferential direction is divided by the slit in the circumferential direction. Forming device for clutch teeth for variable speed gears. 4. A conical positioning hole is formed on the lower surface of the die piece, and an engaging body is provided on the movable receiving member to be pushed upward by an elastic body to engage with the positioning hole. A device for forming clutch teeth for a transmission gear according to claim 1, 2, or 3.