JP3089369B2 - Molding device for cup-shaped products with splines having snap ring grooves - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for forming a splined cup-shaped product having a snap ring groove for fitting a snap ring, used for a clutch drum of a hydraulic clutch of an automatic transmission for a vehicle.

[0002]

2. Description of the Related Art Conventionally, a cup-shaped product of this type has a snap ring groove in which a spline is formed on a peripheral wall of a cup-shaped material made of sheet metal and a part of a spline protruding inwardly of the peripheral wall is depressed outward. It is manufactured by molding. The snap ring groove is generally formed in a separate step after the spline molding. However, an apparatus for simultaneously forming the spline and the snap ring groove is also known from Japanese Patent Application Laid-Open No. 62-14040. This molding device includes a lower die and an upper die, and a die in which a cup-shaped material can be set downward and a tooth groove corresponding to a spline shape is formed on a peripheral surface of the lower die,
A spline forming punch which is radially advanced and retracted toward the tooth space in conjunction with the vertical movement of the upper die is provided, and a snap ring groove forming punch projecting into the tooth groove in the die, and a spline forming punch are provided in the spline forming punch. It is provided with a relief part for the snap ring groove forming punch, and the spline forming punch is advanced radially inward by lowering the upper die, and the peripheral wall of the cup-shaped material is pushed into the tooth groove to form the spline peak. At the same time, the peripheral wall portion corresponding to the relief portion of the punch is prevented from being pushed into the tooth groove by the snap ring groove forming punch, and the groove processing punch is cut into the peak portion with the formation of the spline peak portion, and the snap ring is formed. The groove is formed. However, the product cannot be removed from the die if the groove forming punch bites into the spline ridge, so in this case, the peripheral wall that becomes the open end of the product by reducing the groove width of the lower part of the tooth groove groove forming punch The gap between the peaks of the spline on the lower end side is widened, and the groove forming punch is rotated around the axis of the die by a half pitch of the spline in conjunction with the rise of the upper die, thereby causing the groove forming punch to rotate around the peripheral wall. The product is pulled out of the die while being kept within a wide space between the peaks of the lower end spline.

[0003]

In the above-described apparatus, the width of the ridge on the opening end side of the product becomes narrower, and the pressure receiving area acting on the opening end side acting on the snap ring decreases. There is a problem that the supporting strength of the steel sheet decreases. In view of the above, the present invention provides a forming apparatus for simultaneously forming a spline and a snap ring groove, in which a product can be removed from a die without forming a peak portion on the opening end side of the product to be narrow. Its purpose is to do.

[0004]

In order to achieve the above object,
The present invention is an apparatus for simultaneously forming a spline and a snap ring groove on the peripheral wall of a cup-shaped material made of sheet metal, comprising a lower mold and an upper mold, and the lower mold can be set with the cup-shaped material facing downward. And a die having a tooth groove corresponding to a spline shape formed on a peripheral surface thereof, and a spline forming punch which is moved radially toward and away from the tooth groove in conjunction with the vertical movement of the upper die. In a device in which a snap ring groove forming punch projecting into a tooth groove and a spline forming punch are provided with an escape portion for the snap ring groove forming punch, the snap ring groove forming punch is inserted into a die so as to be protruded and retracted into the tooth groove. And an interlocking mechanism for moving the snap ring groove forming punch in the radial direction in conjunction with the vertical movement of the upper die.

[0005]

The spline forming punch advances radially inward toward the tooth space during the machining of the upper die, and the peak of the spline and the snap ring protruding into the tooth space are formed by the cooperation of the punch and the tooth space. The snap ring groove is formed at the same time by the cooperation of the groove forming punch and the relief of the spline forming punch.
Although this point is not particularly different from the above-described conventional apparatus, according to the present invention, when the upper die is raised, the snap ring groove forming punch is moved inward in the radial direction via the interlocking mechanism and sinks into the groove bottom of the tooth space. Thus, the product can be extracted from the die without forming the peak of the spline on the open end side of the product to be narrow.

[0006]

In the embodiment shown in FIG. 3, as shown in FIG. 3, a spline peak Wa protruding inward from the peripheral wall, and a part of the peak Wa is recessed outward to fit the snap ring a. This is a molding device for forming a cup-shaped product W comprising a clutch drum, having a snap ring groove Wb formed in an opposite direction.

As shown in FIG. 1, the molding apparatus includes a lower die 1 and an upper die 2 that can move up and down. The lower die 1 can be set with a sheet-shaped cup-shaped material facing downward. 2, and a plurality of spline forming punches 4 which are located around the die 3 and which can move back and forth in the radial direction as shown in FIG. The die 3 is formed in a cylindrical shape, a plurality of tooth grooves 3a corresponding to a spline shape are formed on the outer peripheral surface of the die 3, and each punch is formed via a driver cam 5 which is vertically provided by the lowering of the upper die 2. 4 is advanced radially inward toward each tooth space 3a,
The peripheral wall of the material is formed in the tooth groove 3 by the tooth ridge 4a at the tip of each punch 4.
a to form a spline peak Wa.

The die 3 is provided with a plurality of snap ring groove forming punches 6 protruding into the tooth grooves 3a corresponding to the tooth grooves 3a, and the snap ring groove forming punches of the tooth ridges 4a of the spline forming punch 4 are provided. A recess 4b is formed in a portion facing the outer periphery of the spline forming punch 4 so that when the spline forming punch 4 is advanced inward in the radial direction to form the spline peak Wa, the snap ring groove forming punch 6 and the escape portion are formed. 4b, the snap ring groove Wb is formed.

The snap ring groove forming punch 6 is slidably inserted into and supported by a radial guide hole 3 b formed in the die 3, and radiates the punch 6 via an interlocking mechanism 7 when the upper die 2 moves up and down. Moved back and forth in the direction. The interlocking mechanism 7 has a bell crank-shaped lever 8 having one end engaged with a vertically long hole 6a formed in the snap ring groove forming punch 6, and a roller 8a facing the inner periphery of the die 3 attached to the other end. And a cam pin 9 which is slidably mounted on the inner periphery of the die 3 and urged upward by a spring 9a. And
A pad 10 for holding the bottom wall of the cup-shaped material between the die 3 and the die 3 is attached to the upper die 2 by urging downward with a spring 10a, and the cam pin 9 is pushed down via the pad 10 when the upper die 2 is lowered. At this depressed position, the portion of the cam pin 9 facing the roller 8a was formed in the small diameter portion 9b, and the portion of the cam pin 9 facing the radially inner end of the snap ring groove forming punch 6 was formed in the large diameter portion 9c.

By lowering the upper mold 2, FIG.
As shown in (a), the large-diameter portion 9c pushes the snap ring groove forming punch 6 radially outward and protrudes into the tooth groove 3a, and in this state, the spline forming punch 4 advances radially inward. The peak Wa of the spline and the snap ring groove Wb are formed as shown in FIG. After the molding, if the upper mold 2 is raised, the cam pin 9 moves upward by the urging force of the spring 9a,
The large-diameter portion 9c separates above the inner end of the snap ring groove forming punch 6, and the outward pressing of the punch 6 is released. Then, the large-diameter portion 9c contacts the roller 8a and the lever 8 is released. 1 is rotated clockwise in the drawing with the pivot 8b as a fulcrum.
As shown in (b), the snap ring groove forming punch 6 is moved inward in the radial direction and sinks into the groove bottom of the tooth groove 3a. Thus, the punch 6 is not caught on the spline peak Wa below the snap ring groove Wb, and the spline peak w
The product W can be extracted from the die 3 even if a is formed into the same cross-sectional shape over the entire length.

[0011]

As is apparent from the above description, according to the present invention, the product can be removed from the die without forming the peak of the spline at the open end of the product to be narrow. This has the effect of securing a large pressure receiving area against the pressing force to the opening end acting on the snap ring, and improving the support strength of the snap ring.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the apparatus of the present invention, in which (a)
Is a sectional view at the time of molding, and (b) is a sectional view at the time of opening the mold.

FIG. 2 is an enlarged sectional plan view taken along the line II-II of FIG.

FIG. 3 is a perspective view of a product.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lower die 2 Upper die 3 Die 3a Tooth groove 4 Spline forming punch 4b Relief part 6 Snap ring groove forming punch 7 Interlocking mechanism

Continued on the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B21D 53/26 B21D 53/28 B21D 22/30 B21D 37/08 B21D 53/86 B21D 53/88 F16D 13/68

Claims (1)

(57) [Claims] 1. A device for simultaneously forming a spline and a snap ring groove on a peripheral wall of a cup-shaped material made of sheet metal, comprising a lower mold and an upper mold, and setting the cup-shaped material in a lower mold with the cup-shaped material facing downward. A die having a freely formed spline-shaped tooth groove on the peripheral surface thereof, and a spline forming punch radially moved toward and away from the tooth groove in conjunction with the vertical movement of the upper die. In the case where a snap ring groove forming punch projecting into the tooth groove and a spline forming punch are provided with an escape portion for the snap ring groove forming punch, a die is formed so that the snap ring groove forming punch is protruded and retracted into the tooth groove. A snap ring groove forming punch, which is supported in a radially movable manner in a radial direction, and which moves a snap ring groove forming punch in a radial direction in conjunction with the vertical movement of the upper die. A molding device for cup-shaped products with splines having a pulling groove.