JP3372668B2 - Apparatus for forming clutch teeth for transmission gears - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission gear having a spline-type clutch integrally formed on the outer periphery of a boss.
In particular, the present invention relates to a clutch tooth forming apparatus in which the clutch teeth are formed in a reverse tapered shape in which the tooth thickness at the root is smaller than the tooth thickness at the shaft end. 2. Description of the Related Art As a prior art, Japanese Patent Laid-Open Publication No. 63-120
No. 958, namely FIG. 11 and FIG.
No. 12 was found. In FIG. 11 , reference numeral 1 denotes a lower die mounting base, and a lower die 2 and a cylindrical case 3 are concentrically arranged on a shaft core portion and an outer peripheral portion of the upper surface of the mounting die 1 and fixed by bolts. An annular flange 4 is fitted between the case 2 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 plurality of die insertion holes 2a having a circular cross section and a flat upper surface cut in the upper surface in a radial direction, and each die insertion hole 2a has a round bar-shaped upper surface. The die 6 cut into a flat shape is slidably fitted in the radial direction. The die 6 has a molding tooth 6a having a tooth thickness increasing upward at an inner end portion on the shaft center side, a slope inclined upward and inward at an outer end portion, and a pin hole parallel thereto. (All symbols are omitted). [0004] The case 3 integrally has a die holder 3a which is bent in the axial direction at the upper end thereof. The die holder 3a holds down the die 6 described above to regulate the rotation of the die 6. Up and down cam insertion holes 7 are formed at a predetermined pitch in the circumferential direction on the outer periphery of the die holder 3a of the case 3;
A cam 8 is slidably fitted in each of the cam fitting holes 7 and fixed to the flange 4 by bolting. Each of the cams 8 has an upper end protruding slightly upward from the case 3, and a pin 9 is fixed to the lower inside of the cam 8 by being inclined inward and standing on an inner surface facing the pin 9. To form a cam surface 8a having an inclination angle equal to.
The outer end of the die 6 is projected into the cam insertion hole 7 so that the pin hole is slidably inserted into the pin 9, and the slope of the outer peripheral end of the die 6 is cam surface 8 a. Contact. The intermediate product 10 is placed on the shaft center of the lower die 2 described above. The intermediate product 10, as shown in FIG. 13, the outer periphery of the boss portion in which the lower is a smaller diameter, having a primary clutch teeth 11 a of the spline teeth extending downward with an equal tooth thickness, these respective primary clutch engaging the teeth 11 a on splines 6a of each die 6 described above. Then, while the intermediate product 10 is pressed by the upper die 12, each cam 8 is pressed and moved downward by the upper die mount (punch) 13, and each die 6 is moved in the axial direction by the cam surface 8 a. The primary clutch teeth 11a are formed by forming teeth 6a of the die 6.
Pressurized in the axial direction, as shown in FIG. 14, the tooth thickness of the root portion (upper) forms a reverse tapered clutch teeth 11 becomes smaller than the tooth thickness of the shaft end portion (bottom). [0007] In the above-mentioned conventional one, a die-insertion hole 2a having a circular cross section with a cut upper surface is radially formed in the lower die 2, and a rod-like hole is formed in the die-insertion hole 2a. The dies 6 are slidably inserted, and the same number of cam insertion holes 7 as the dies 6 are formed in the case 3 at a predetermined pitch in the circumferential direction. Were individually fitted, the structure became complicated and the number of parts increased,
There are drawbacks that the manufacturing cost is increased and the assembly is troublesome. SUMMARY OF THE INVENTION An object of the present invention is to provide a novel gear tooth forming apparatus for a transmission gear that has solved the above-mentioned disadvantages. [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 tapered cam surface in which an upper inner peripheral surface is reduced downward, and a movable receiver is vertically movably fitted to a lower portion of the die hole. At the end, a number of die pieces are provided in which a plurality of molding teeth whose tooth thickness increases upward in the circumferential direction are provided, and each die piece is directed from the inner peripheral side to the outer peripheral side.
It is formed into a fan shape in plan view that is wide, and the inner end
A short slit that divides each of the molded teeth in the circumferential direction
A dispersion hole at a position spaced from the slit to the outer peripheral side.
Each die piece is formed in the respective circumferential direction.
Both end surfaces are brought close to each other and radially arranged on the outer peripheral portion of the movable receiving member, and the outer peripheral surface of each die piece is brought into contact with the cam surface of the die hole, and extends vertically in the lower outer periphery of the boss portion and extends in the circumferential direction. An intermediate product having a large number of primary clutch teeth formed at a predetermined pitch is provided, the intermediate product is placed on top of each die piece, and each primary clutch tooth is engaged with a molding tooth of the die piece, and each of the die A punch for pressing and moving the piece downward together with the intermediate product is provided. 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 portion of a mold main body 16, places an intermediate product 25 on the lower mold 17, and removes the placed intermediate product 25. Pressing is performed toward the lower mold 17 by the punch 20 to form a predetermined shape. That is, the lower mold 17 has primary spur teeth 18 having the same tooth thickness in the vertical direction on the inner peripheral part thereof, and an annular throttle projection 19 on the inner peripheral side of the primary teeth 18.
And the punch 20 is provided on the inner peripheral side with the first punch.
The punch 21 and the outer peripheral side. The second punch 22 is fixed to the ram side, and the aperture
An annular throttle projection 21a facing 9 is formed. Also,
Intermediate product 25 is rim portion 25a of the gear teeth formed on the outer periphery are formed, it is formed primary clutch teeth 26 of the spline teeth are on the outer peripheral surface of one (bottom) of the inner peripheral side of the boss portion 25b to Do <br/> You. 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 to the lower mold 17. 2 and 3, while the inner projection of the boss 25b of the intermediate product 25 is pinched by the squeezing projections 19 and 21a to plastically flow in the outer peripheral direction, that is, in the direction of the primary molding teeth 18, as shown in FIGS. Then, the primary clutch teeth 26 are finished to a high-precision spline tooth profile having an equal tooth thickness from the base of the boss 25b toward the lower end. In addition,
23 is an intermediate product 25 having finished the primary clutch teeth 26
Is an extruding pin that pushes out from the lower mold 17 upward. In FIG. 4, reference numeral 30 denotes a clutch tooth forming device for forming the primary clutch teeth 26 in a reverse taper shape in which the tooth thickness at the root (upper end) is smaller than the tooth thickness at the shaft end (lower end). Yes, as follows: That is, 31 is a mold main body, and the mold main body 31 is provided on the upper part of a cylindrical holding ring 32 by a cam cylinder 3 reinforced by a clamp 34.
3 is coaxially fixed, and a die hole 33 a is formed by the cam barrel 33. The die hole 33a is formed in a tapered cam surface 33b whose upper inner peripheral surface is reduced downward.
The cam cylinder 33 is press-fitted and fixed integrally with a clamp 34,
The clamp 34 is detachably fixed to the holding ring 32 by a connector (not shown). The lower part of the holding ring 32 is closed by a deposit (not shown), and an elastic body 35 such as rubber and a movable receiver 36 are sequentially stacked on the upper part of the deposit, and the movable receiver 36 is interposed via the elastic body 35. Are fitted so as to be able to move up and down, and an annular positioning ring 39 is fixed to the outer peripheral portion of the upper part of the movable receiver 36. The engaging members 37 made of a ball are fitted to the positioning ring 39, and each of the engaging members 37 is urged upward by a spring 38. The engaging body 37 may have a pin-shaped upper end formed into a conical surface or a hemispherical surface to urge upward. The positioning ring 39 restricts downward movement downward by stopper balls 23 provided at three circumferential positions at the lower end of the cam barrel 33. As a result, the positioning ring 39, a die piece 40, a cam cylinder 33, and a clamp 34, which will be described later, are detachably attached to the holding ring 32 as a unit. On the upper surface of the positioning ring 39, a number of die pieces 40 are radially arranged and mounted. 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 40 a of the die piece 40 is formed in a fan shape in a plan view that becomes wider from the inner peripheral side to the outer peripheral side (FIG. 6, FIG. 7) so that the circumferentially opposite end surfaces of the die pieces 40 adjacent in the circumferential direction are brought closer to each other. Also, two formed teeth 41 whose tooth thickness increases upward in the circumferential direction are formed at the inner end portion of the die piece main body 40a in the circumferential direction, and the outer peripheral surface is formed on a slope 42 that is inclined inward downward. I do. In addition, each of the above
As shown in FIGS. 5 to 7, each of the molded teeth 41, 4
1 extending in the radial direction (left / right direction) that divides 1 in the circumferential direction
The lit 43 is formed short on the inner end (left end) of the main body 40a.
And the dispersion holes 44 are formed on the outer peripheral side (right
Side) and separate them according to the load during molding.
The cracks generated in the outer peripheral direction from the
4 will be regulated. Further, a conical positioning hole 45 is formed in the center of the lower surface of the die piece main body 40a,
An arc-shaped groove (not shown) centered on the axis of the cam cylinder 33 is formed at the middle part in the inside and outside (left and right) directions of the lower part of the die piece main body 40a. The die pieces 40 are arranged and mounted on the upper surface of the above-described positioning ring 39 in a radial pattern, and a spring 48 formed of a spring steel wire into a ring shape is fitted into the groove to form the die pieces 40. The inclined surface 42 at the outer peripheral end is fixed to the cam surface 3 of the die hole 33a.
3b, and a positioning hole 45 formed in the lower surface of each die piece 40 is engaged with the engaging body 37 on the positioning ring 39 side.
The die ring 40 is restricted from moving upward by a stopper ring 46 screwed to the upper end of the clamp 34.
Then, the intermediate product 25-
1 is placed on the upper part of each die piece 40, and each primary clutch tooth 26 is engaged with the molding tooth 41 of each die piece 40, and each die piece 40 is punched through the intermediate product 25-1 through the intermediate product 25-1. Is moved downward. Then, each die piece 40 is moved in the axial direction by the cam surface 33b, and the 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 such that the tooth thickness at the root (upper) is smaller than the tooth thickness at the shaft end (lower). In this case, as shown in FIG. 6, each die piece 40 has two molded teeth 41, 41 integrally in the inner peripheral portion, and these molded teeth 41, 41 are slits in the inner peripheral portion. 4
3 and a crack extending from the slit 43 to the dispersing hole 44 to allow a slight circumferential contact and movement of each other, so that the respective primary clutch teeth 26 can be pressed smoothly. Further, when the molded teeth 41 of each die piece 40 receive an upward load when the molded intermediate product 25-1 is released upward by the extrusion pin 49, each die piece 40 moves the stopper ring 46. As a result, the formed clutch teeth 27 smoothly separate from the formed teeth 41 of each die piece 40. FIG. 10 shows a second embodiment of the clutch tooth forming apparatus. In this apparatus, a punch 50 is formed by a first punch 51 on an inner peripheral side and a second punch 52 on an outer peripheral side, and the first punch 51 is moved downward by a spring 53 at the center of a pressing plate 54 fixed to a ram. The second punch 52 is fixed to the outer peripheral portion of the pressure plate 54 in a cylindrical shape. Then, a point which is adapted by the first punch 51 presses the intermediate product 25-1 molded by the primary molding apparatus 15 downwardly to press the respective die pieces 40 downward by the second punch 52, is above
Unlike the first embodiment described above, the others are substantially the same as the first embodiment.
It has a structure. It is formed on the die piece 40.
The number of molded teeth 41 is the number of teeth of clutch teeth 27, diameter,
Increase or decrease as appropriate depending on the size of the device. As is apparent from the above description, according to the present invention, a plurality of molding teeth are formed at the inner end of the die piece in the circumferential direction .
And each die piece widens from the inner circumference to the outer circumference.
It is formed in a fan shape in a plan view to be the width, and each of the above-mentioned
A short slit that divides the teeth in the circumferential direction
A dispersion hole is formed at a position away from the outer periphery of the die , and the die pieces are radially arranged and mounted on the movable receiver, and the outer peripheral surface is brought into contact with the tapered cam surface of the die hole. , the number of components is reduced as well as the structure is simplified, an effect of assembly and maintenance is facilitated with less expensive.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of a forming apparatus for forming an intermediate product according to the present invention. FIG. 2 is a sectional view of a main part of an intermediate product. FIG. 3 is a view showing A in FIG. 2; 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 of the present invention. FIG. 6 is a plan view of FIG . 5; FIG. 7 is a bottom view of FIG . 5; FIG. 8 is a sectional view of a main part of a molded product in which clutch teeth are molded. FIG. 9 is a diagram shown in B of FIG. 8; FIG. 10 is a sectional view of a main part of a clutch tooth forming apparatus according to a second embodiment of the present invention. FIG. 11 is a sectional view of a conventional clutch tooth forming apparatus.
It is. FIG. 12 is a plan view of a die fitting hole of FIG . 11; FIG. 13 is a sectional view of a conventional intermediate product. FIG. 14 shows a conventional molded product in which clutch teeth are molded.
FIG. [Description of Signs] 15 Primary molding device 16 Mold main body 17 Lower mold 18 Primary molding teeth 19 Squeezing projection 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 Mold main body 32 Holding ring 33 Cam cylinder 33a Die hole 33b Cam surface 34 Clamp 35 Elastic body 36 Movable catch 37 Engaging body 38 Spring 39 Positioning ring 40 Die piece 41 Molding tooth 42 Slope 43 Slit 44 Stress distribution hole 45 Positioning hole 46 Stopper ring 48 Spring 49 Extrusion pin 50 Punch 51 First punch 52 Second punch 53 Spring 54 Pressure plate

Continuation of the front page (56) References JP-A-4-231140 (JP, A) JP-A-53-69998 (JP, A) JP-A-4-251616 (JP, A) JP-A-55-57341 (JP, A) , A) JP-A-7-71566 (JP, A) JP-A-2-16246 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B21J 1/00-13/14 B21J 17/00-19/04 B21K 1/00-31/00 F16D 11/00

Claims (1)

(1) A die hole (33a) formed in a tapered cam surface (33b) whose upper inner peripheral surface is reduced downward in a mold main body (31). And a movable receiving metal (36) is vertically movably fitted to a lower portion of the die hole (33a), and a plurality of molding teeth (41) having a tooth thickness increasing upward at an inner end thereof in a circumferential direction. It provided a number of forming dies piece (40), each
The die piece (40) becomes wider from the inner circumference to the outer circumference.
In addition to forming the fan shape in a plan view,
A short slit (43) for dividing the teeth (41) in the circumferential direction
At a position separated from the slit (43) to the outer peripheral side.
Each of the die pieces is formed with a divergent hole (44).
(40) are arranged radially on the outer peripheral portion of the movable receiver (36 ) with their respective circumferential end surfaces close to each other , and the outer peripheral surface of each die piece (40) is formed in a die hole (33a). ) Abuts on the cam surface (33b) of the intermediate product (25-), which has a large number of primary clutch teeth (26) extending vertically in the lower periphery of the boss (25b) and formed at a predetermined pitch in the circumferential direction. 1), the intermediate product (25-1) is placed on top of each die piece (40), and each primary clutch tooth (26) is engaged with the molding tooth (41) of the die piece (40). Combine the die pieces (40) with the intermediate product (25-
A gear forming apparatus for a transmission gear, comprising: a punch (50) for pressing and moving downward together with 1).