JPS63230245A - Die for forming grooved cup - Google Patents

Abstract

PURPOSE:To improve the pitch accuracy of a groove and to reduce a forming cost by arranging the die forming the groove forming teeth of specific pitches respectively on the inner peripheral face and outer peripheral face and a punch, and subjecting a cup like blank to push-forming into a die. CONSTITUTION:A cylindrical die 10 having groove forming teeth 11 on the inner peripheral face is provided and a circular columnar punch 12 having the teeth 13 for groove forming is arranged on the outer peripheral face as well. In this case, the teeth 11 of the die 10 are formed in equal pitches according to the number of grooves to be formed on the external case as a product and an upper end 11a is formed in the inclined face inclining in specific down slope. The external case blank stock 15 formed in cup shape in advance is set inside the die 10 and after arranging a counter punch 14 the punch 12 is descended to form a groove 16 on the blank 15. Due to the groove 16 being formed on the blank 15 with one punching the pitch accuracy of the groove 16 is improved to reduce the forming cost.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a mold for forming a grooved cup, and in particular to a mold for forming a grooved cup that can form even small pitch grooves with one punch. be.

[Conventional technology]

2. Description of the Related Art In automatic transmissions with torque converters used in passenger cars and the like, a multi-plate clutch is used as a means for transmitting power from a driving side to a driven side. This multi-disc clutch includes a cup-shaped outer case in which grooves parallel to the axis are formed at equal pitches on the inner circumferential surface, and a plurality of driving and driven discs housed in the outer case in an alternating manner. The outer circumferential edge of the driving disk is engaged with a groove in the outer case, and the inner circumferential edge of the driven disk is engaged with a driven body.

In such multi-disc clutches, grooves are generally formed on the outer case by a plastic working method using a mold.

Conventionally, as shown in FIG. 5, as a method for forming grooves in the outer case, an outer case material 3 is formed into a cup shape in a ring-shaped die 1 in which recesses 2 are formed at a predetermined pitch on the inner circumferential wall.
After that, cam punches 4 (only one is shown in the drawing, but there are as many as the recesses 2 of the die 1)
by moving the cam punch 4 in the direction of the arrow Y in FIG. 6 by moving the cam punch 4 in the direction of the arrow Y in FIG. By half-blanking from the inside to the outside, grooves 6 corresponding to the number of recesses 2 of the die 1 are formed, thereby forming the outer case 3A.

[Problem that the invention seeks to solve]

In the above-mentioned outer case forming method, the grooves 6 are formed by the cam punch 4 that is slid in the radial direction by the pressing member 5. Therefore, in order to increase the power transmission torque of the multi-disc clutch, the number of grooves in the outer case is increased. For example, even if an attempt was made to increase the cam punch 4 to twice that in the case shown in FIG. The number of grooves shown is the limit.

Therefore, for example, when trying to double the number of grooves in the outer case 3A as shown in FIG. 6, first form the grooves 6 using the cam punch 4 as shown in FIG. Set it on die 1 with a 1/2 pitch shift,
A possible method is to operate the cam punch 4 again to form new grooves between the grooves formed in the previous process. However, with this forming method, the grooves are processed in several steps, which reduces the pitch accuracy of the grooves, resulting in grooves that do not come into contact with the engaging parts of the clutch plate. There was a problem that the torque could not be obtained and the torque capacity decreased.

[Purpose of the invention]

The present invention was made in order to solve the above-mentioned problems, and an object of the present invention is to provide a mold for forming a grooved cup that can process even fine pitch grooves with one punch and has good groove pitch accuracy. shall be.

[Means for solving problems]

The mold for forming a grooved cup according to the present invention has groove forming teeth formed on the cylindrical inner circumferential surface with a predetermined pitch and notch, the groove forming teeth being an inclined surface whose material insertion side is inclined inward at a predetermined downward slope. a die, a punch that has groove forming teeth formed at a predetermined pitch on the outer peripheral surface corresponding to the teeth of the die, and that pushes the cup-shaped material into the die, and is movable from the side where the material is reversely inserted into the die. It consists of an inserted counter punch.

[Action of the invention]

In the present invention, the integrated punch pushes the cup-shaped material into the die, and the punch and the inclined parts of the teeth, which serve as cutting blades, half punch the peripheral wall of the material from the outside to the inside to form a groove. Therefore, groove machining is possible with one punch, and the pitch accuracy of the machined grooves is also improved.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 3 show an example of a mold for forming a grooved cup according to the present invention, and FIG. 1 shows the mold partially cut away, with grooves formed on the inner peripheral surface It includes a cylindrical die 10 having teeth 11, a cylindrical punch 12 having groove-forming teeth 13 on its outer peripheral surface, and a counter punch 14 inserted into the die 10 from the lower surface side.

The teeth 11 of the die 10 are formed in a uniform pinch according to the grooves formed in the outer case of a grooved cup, for example, a multi-disc clutch, and
A is a slope 1 which slopes at a predetermined downward slope from the inner circumferential surface of the die 10 to the tip. In addition, the above punch 1
The teeth 13 of the die 10 are formed at equal pitches so as to correspond to the spaces between the adjacent teeth 11 of the die 10.

When molding a grooved outer case with the mold configured as described above, as shown in FIG. 2, the outer case material 15 previously formed into a cup shape is set in the die 10,
The punch 12 is lowered to push the outer case material 15 into the die 10. Then, the material 1 that is pushed in by the punch 12
While the peripheral wall of the die 10 passes through the inclined upper end 11a of the teeth 11 of the die 10, the punch 12 is half punched from the outside to the inside due to the diametrical shear force applied to the peripheral wall. Grooves 16 corresponding to the teeth 13 are integrally formed.

Since the punch 12 is thus integrated, the precision of pinching the grooves in the molded outer case is good, and even if 16 pinches are made of a tight rope, these grooves can be formed with one punch.

In the above embodiment, the teeth 11 of the die 10 are formed integrally with the die body, but the teeth 11
may be configured separately from the die main body so that it can be attached in a nested manner. In this case, only the damaged or worn teeth can be replaced.

Further, as shown in FIG. 4, the inclined upper end 11a of the teeth 11 of the die 10 is formed to match the groove size formed in the outer case, and the front surface 11b and both side surfaces excluding the inclined upper end 11a are formed. 11C.

By providing a relief in 11C, seizure of the outer case product can be prevented.

〔Effect of the invention〕

As described above, according to the present invention, on the inner peripheral surface of the cylindrical die,
The material insertion side is provided with teeth that slope inward at a predetermined downward slope at a desired pitch, and teeth are formed on the outer circumferential surface of the punch to correspond to the teeth of the die, and the material is pushed into the die by this punch. Since the grooves corresponding to the number of teeth mentioned above are formed on the peripheral wall of the material by half punching, the pitch accuracy of the grooves formed in the cup material is improved, and even fine pitch grooves can be formed with a one-punch operation. As a result, molding costs can be reduced, the mold can be made simple, and it is also suitable for machining grooves on the outer case of multi-disc clutches.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway perspective view showing an example of a mold for molding a grooved cup according to the present invention, FIG. 2 is an explanatory diagram showing the relationship between the mold and the material during groove molding, and FIG. The figure is a partially cutaway perspective view showing the relationship between the mold and the material, showing a state in which a groove has been half-blanked into the material, and FIG. 4 is a perspective view of a die tooth portion showing another embodiment of the present invention. , Fig. 5 is a partially cutaway perspective view of a mold for molding a conventional grooved cup, and Fig. 6 is a partially cutaway perspective view showing the relationship between the mold and the material during groove molding. be. 10...Die, 11...Teeth, lla...Slope part,
12...Punch, 13...Teeth, 14...Counter punch, 15...Material. Patent applicant AIDA Engineering Co., Ltd. Figure 1 Figure 8

Claims (3)

[Claims] (1) A die with groove forming teeth formed at a predetermined pitch on the cylindrical inner circumferential surface, the material insertion side being an inclined surface inclined inward at a predetermined downward slope, and an outer circumferential surface corresponding to the teeth of the die. Molding of a grooved cup consisting of a punch that has groove forming teeth formed at a predetermined pitch and that pushes the cup-shaped material into the die, and a counter punch that is movably inserted into the die from the material reverse insertion side. Mold for use. (2) A mold for forming a grooved cup according to claim 1, wherein the teeth of the die can be installed in a nested manner. (3) A mold for forming a grooved cup according to claim 1 or 2, wherein the teeth of the die have a relief in a portion excluding the inclined portion thereof.