JP2821998B2 - Snap ring groove forming device for clutch drum - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circumferential direction in which a snap ring for retaining a clutch plate mounted in a clutch drum is fitted into a toothed portion of an internal spline formed on a peripheral wall portion of the clutch drum. The present invention relates to an apparatus for press-forming a snap ring groove extending.

[0002]

2. Description of the Related Art Conventionally, this type of apparatus has been disclosed in Japanese Unexamined Patent Publication No.
The thing described in 41858 gazette is known. This device has a lower die and an upper die that can move up and down. A work support member that can externally set the clutch drum is set up on the lower die, and the diameter of the clutch drum is set outside the arrangement portion of the work support member. A first slider and a second slider slidable in two directions are provided in upper and lower two stages, and a work receiver that can be brought into contact with the outer peripheral surface of the clutch drum is fixed to a radially inner end of the upper first slider, An upwardly bent portion is formed at the radially inner end of the lower second slider, and a punch that can contact the toothed portion of the internal spline is fixed to the upper end of the bent portion, and the upper die is lowered. The first slider and the second slider are respectively pushed radially inward and radially outward through a cam mechanism through the cam mechanism. Form a snap ring groove by cutting a punch into the tooth ridge It is way.

In this cam mechanism, a drive cam capable of abutting on a radially outer end of a first slider is suspended from an upper die, and a second slider is extended to an outer position of the drive cam. An upward bending portion is formed at the outer end, and the first slider is pushed inward in the radial direction with the radial outer end portion as an action point by lowering the driving cam, and the second slider is moved outward in the radial direction. It is configured to be pushed radially inward with the bent portion at the end as the point of action.

[0004]

In the above-mentioned prior art, the point of action of the cam mechanism with respect to the second slider is at the bent portion of the outer end of the second slider, so that the cam mechanism is attached to the bent portion of the inner end of the second slider. The distance between the punch to be applied and the point of action is increased, so that the second slider is easily bent during molding, so that the punch cannot be cut into the teeth of the internal spline to the required depth, and the snap ring groove is formed. There is a problem that accuracy is deteriorated. In view of the above, an object of the present invention is to provide a molding device capable of accurately molding a snap ring groove.

[0005]

In order to achieve the above object,
The present invention is an apparatus for press-forming a snap ring groove extending in a circumferential direction at a tooth portion of an internal spline formed on a peripheral wall portion of a clutch drum, comprising a lower die and an upper die that can be raised and lowered. In addition, a work support member capable of externally setting the clutch drum is provided upright, and a first slider and a second slider slidable in the radial direction of the clutch drum are provided in two stages vertically outside the arrangement portion of the work support member. And a work receiver that can be brought into contact with the outer peripheral surface of the clutch drum is fixed to a radially inner end of the upper first slider, and an upwardly bent portion is formed to a radially inner end of the lower second slider. Is formed, and a punch that can contact the toothed portion of the internal spline is fixed to the upper end of the bent portion, and the first slider and the second slider are respectively moved in the radial direction via the cam mechanism by lowering the upper die. Push inward and outward in the radial direction to A cam mechanism for driving a first slider, wherein the cam mechanism drives a first slider, in which a snap ring groove is formed by making a punch bite into a toothed portion of an internal spline in a state where a workpiece receiver is in contact with an outer peripheral surface of a drum. And the second
A second cam mechanism for driving the slider, wherein the first cam mechanism pushes the first slider radially inward with the radial outer end of the first slider as an action point when the upper die is lowered. The second cam mechanism is provided on the lower side of the second slider, the first driven cam which is pushed inward in the radial direction when the upper die is lowered, and is provided on the outer periphery of the lower portion of the work supporting member. A second driven cam which is responsively moved upward by a radially inward movement of the first driven cam, and a second slider having a radially inner end of the second slide as an action point when the second driven cam is moved upward. Are configured to respond radially outward. In this case, in a state where the upper edge of the sliding portion of the radial inner end of the second slider with respect to the second driven cam is equal to or higher than the arrangement height of the punch and the punch bites into the toothed portion of the internal spline. It is preferable that the second driven cam is configured to contact the sliding contact portion over the upper edge thereof,
The first cam mechanism is constituted by a drive cam provided on the upper die, which comes into contact with a radially outer end of the first slider when the upper die is lowered, and the first cam mechanism is provided on a radially outer end of the first slider. A downward bent portion is formed at a radially outer end of the second slider so as to have a radial gap therebetween, and enters the gap from below to separate the first slider and the second slider from each other in the radial direction. An annular return cam concentric with the work supporting member, which is to be moved backward and inward in the radial direction, is provided so as to be urged upward to the lower mold and pushed down by the drive cam when the upper mold is lowered, Further, it is preferable that the first driven cam is pushed radially inward by the downward movement of the return cam.

[0006]

When the upper die is lowered, the first cam mechanism causes the first die to move.
The slider is pushed inward in the radial direction so that the work receiver comes into contact with the outer peripheral surface of the clutch drum, and the second slider is pushed outward in the radial direction by the second cam mechanism, so that the punch is moved to the tooth of the internal spline. Then, the snap ring groove is press formed. Here, the point of action of the second cam mechanism on the second slider is the radially inner end of the second slider, so that the second slider is positioned radially outward as close as possible to the punch attached to the bent portion of the inner end. As a result, the bending accuracy of the snap ring groove does not deteriorate due to the bending of the second slider. By the way, a horizontal forming reaction force caused by the internal spline biting into the tooth ridge portion acts on the punch at the time of groove forming, and bending stress due to the forming reaction force is applied to the punch mounting portion at the bent portion at the inner end of the second slider. , The fatigue of the punch mounting portion is caused by the repeated forming operation, and a crack starting from the punch mounting portion may be formed in the bent portion. However, as described above, if the second driven cam contacts the sliding contact portion of the second slider over the upper edge of the sliding contact portion which is set at the same level or higher than the height of the punch, the forming reaction force acting on the punch is reduced. The second driven cam is received on the line of action of the reaction force, so that bending stress does not act on the punch mounting portion of the second slider, the forming accuracy of the snap ring groove is further improved, and the punch mounting portion is formed. Fatigue hardly occurs and durability is improved.

Further, when the upper die is raised, the first slider and the second slider are moved.
It is necessary to move the slider back and forth radially inward and radially inward, respectively, to separate the work receiver and the punch from the outer peripheral surface of the clutch drum and the toothed portion of the internal spline, respectively. Conventionally, each first slider and each second slider are urged radially outward and radially inward by separate urging members, respectively. And the structure becomes complicated. On the other hand, if the return cams are provided as described above, all the first sliders and all the second sliders return to the radially outward and radially inward directions by a single return cam when the upper die is raised. And the structure is simplified. Further, the return cam is pushed down by the drive cam constituting the first cam mechanism when the upper die is lowered, and the first driven cam of the second cam mechanism is pushed in the radial direction with the pushing down. Therefore, the return cam also functions as a drive cam of the second cam mechanism, and the structure can be further simplified.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the illustrated embodiment, the present invention is applied to an apparatus for press-forming a snap ring groove C extending in a circumferential direction at a tooth ridge B of an internal spline formed on a peripheral wall of a clutch drum A shown in FIG. It was done. In addition, snap ring groove C
A snap ring is fitted into the clutch drum A to prevent the clutch plate to be fitted and engaged with the internal spline.

As shown in FIG. 1, the forming device of the snap ring groove C includes a lower die 1 and an upper die 2 which is raised and lowered by a ram (not shown). The lower die 1 is provided with a hollow work supporting member 3 on which a clutch drum A can be externally set, and a large-diameter flange portion 3a is formed at an upper end of the supporting member 3 so as to form the flange 3a. A tooth profile that engages with the internal spline of the clutch drum A is formed on the outer periphery, and a knockout plate 4 is provided on the flange portion 3a, and the plate 4 is biased by a spring or the like provided on the inner periphery of the lower end portion of the work supporting member 3. It was urged upward by means 4a via rod 4b.

A cylindrical guide block 5 is provided in the lower die 1 so as to surround the work supporting member 3, and the upper first slider 6 and the lower second slider 7 are mounted on the guide block 5 by a clutch drum. A was slidably supported in the radial direction of A. The guide block 5 is composed of three members: a lower block 5a that supports the second slider 7, an upper block 5b that supports the first slider 6, and an upper lid 5c.

A plurality of the first sliders 6 are provided at a constant pitch in the circumferential direction, for example, six at a pitch of 60 °. The abutting work receiver 8 was attached. Workpiece holder 8
Are formed on the radially inner end face of the clutch drum A to fit into the concave portion of the outer peripheral surface of the clutch drum A which matches the tooth ridge portion B of the internal tooth spline. Is formed with a concave groove 8a serving as a place where the meat escapes when the groove is formed.

The number of the second sliders 7 is equal to the number of teeth of the internal spline. The second sliders 7 rise upward at the radially inner end of each second slider 7 in the space below the flange portion 3a of the work supporting member 3. Forming a bent portion 7a;
The punch 9 was attached to the outside of the upper end of the.

The first slider 6 is pushed inward in the radial direction via the first cam mechanism 10 by the lowering of the upper mold 2, and the second slider 7 is moved by the lowering of the upper mold 2 to the second cam mechanism. 11 and is pushed radially outward through the upper die 2.
The first slider 6 and the second slider 7 are moved back by the return cam 12 radially outward and radially inward at the time of rising.

In more detail, the first cam mechanism 10 includes:
The upper die 2 is composed of one drive cam 10a provided corresponding to each first slider 6. According to the lowering of the upper die 2, the slope 10b formed on the inside of the lower end of the drive cam 10a has the first shape. The first slider 6 is pressed inward in the radial direction by contacting the slope 10 c formed at the radially outer end of the slider 6.

The return cam 12 is formed in an annular shape concentric with the work supporting member 5 and is externally movably mounted on the outer periphery of the guide block 5, and is provided at a radially outer end of the first slider 6 with a second slider. 7, a downwardly bent portion 6a facing the radially outer end portion with a gap in the radial direction is formed, and a cam portion 12a facing the gap is projected from the return cam 12, and
A contact portion 12b facing the lower end of the driving cam 10a is provided in a protruding manner. Then, the return cam 12 is urged upward by urging means 12c such as springs provided at four locations in the circumferential direction, and when the upper die 2 is raised, the return cam 12 is pushed up by the urging force of the urging means 12c. The cam portion 12a enters the gap and the cam portion 1
The tapered surface 12d on the inner periphery of 2a abuts on the slope 12e at the radially outer end of the second slider 7, and the second slider 7 is moved inward in the radial direction, and the tapered surface 12f on the outer periphery of the cam portion 12a. Is the slope 12 at the lower end of the bent portion 6a of the first slider 6.
g, and the first slider 6 is moved outward in the radial direction.

The second cam mechanism 11 includes a first driven cam 11 a which is positioned below the second slider 7 and is slidably inserted in the radial direction in the guide block 5, and is vertically mounted on a lower outer periphery of the work supporting member 3. And a cylindrical second driven cam 11b externally slidably mounted on the first cam 11b.
It is used as a driving cam for the second cam mechanism 11 which cooperates with the driven cam 11a. When the return cam 12 is pushed down via the drive cam 10a of the first cam mechanism 10 due to the lowering of the upper die 2, the tapered surface 11c at the lower inner peripheral portion of the return cam 12 is moved radially outward of the first driven cam 11a. The first driven cam 11a is pushed inward in the radial direction by contacting the inclined surface 11d at the end, and the inclined surface 11e at the radially inner end of the first driven cam 11a contacts the tapered surface 11f below the second driven cam 11b. The second driven cam 11b is pushed up in contact with the second driven cam 11b, and the upper tapered surface 11g of the second driven cam 11b is
The second slider 7 is pushed outward in the radial direction by contacting the slope 11h at the radially inner end of the second slider 7. First driven cam 11
A plurality is provided in the circumferential direction by equal pinching so that the second driven cam 11b can be evenly pushed up at a plurality of locations around the second driven cam 11b.

The slope 11h serving as a sliding contact portion of the second slider 7 with the second driven cam 11b is formed so that the upper edge thereof is at the same level or higher as the height at which the punch 9 is arranged. The second driven cam 11b abuts on the slope 11h over the upper edge thereof in a state where the second driven cam 11b bites into the tooth ridge portion B.

The upper die 2 is provided with a work holder 13 in addition to the drive cam 10a described above. The work retainer 13 is vertically movably supported by a guide bar 13a suspended from the upper die 2, and is urged downward by urging means 13b such as a spring.

When forming the snap ring groove C, the clutch drum A is extrapolated and set on the work supporting member 3 with the upper die 2 raised, and then the upper die 2 is lowered. According to this, first, the work presser 13 comes into contact with the shoulder A1 of the clutch drum A, and the clutch drum A is pushed down together with the knockout plate 4 against the urging force of the urging means 4a. Faces between the work receiver 8 and the punch 9. Next, the first slider 6 is pushed inward in the radial direction by the driving cam 10a to
Abuts on the outer peripheral surface of the clutch drum A, and further, the drive cam 10a comes into contact with the contact portion 12b of the return cam 12, and the return cam 12 is pushed down, via the first driven cam 11b and the second driven cam 11c. The second slider 7 is pushed radially outward.

According to this, the punch 9 bites into the tooth ridge B of the internal spline, and the snap ring groove C is press-formed. In this case, according to this embodiment, the second slider 7 is pressed radially outward by the second cam mechanism 11 as close to the punch 9 as possible, so that the punch 9 The snap ring groove C is formed with high accuracy without being affected by the bending of the groove. Also,
When the punch 9 bites into the tooth ridge B, the second driven cam 1
1b is in contact with the second slider 7 over a range equal to or higher than the height at which the punch 9 is arranged, so that the horizontal forming reaction force acting on the punch 9 is moved along the line of action of the reaction force by the second driven cam. 11b. Therefore, the second slider 7
No bending stress due to the forming reaction force acts on the punch mounting portion of the bent portion 7a, and the generation of cracks due to fatigue of the punch mounting portion is effectively prevented.

When the snap ring groove C is formed as described above, the upper die 2 is then raised. According to this, the return cam 12 moves upward, and the first slider 6 and the second slider 7 are moved. The workpiece receiver 8 and the punch 9 are respectively displaced from the outer peripheral surface of the clutch drum A and the toothed portion B respectively, and are then moved outward in the radial direction and inward in the radial direction, respectively. The restraint is released and the clutch drum A is pushed up by the knockout plate 4. Then, when the upper mold 2 is completely lifted, the clutch drum A is removed from the work supporting member 3, and one operation is completed.

[0022]

As is apparent from the above description, according to the present invention, the snap ring groove can be formed with high precision, and the second driven cam of the second cam mechanism is provided on the second slider. The durability can be improved by contacting as described above, and the structure can be simplified by providing the return cam as in the invention of claim 3.

[Brief description of the drawings]

FIG. 1 is a cutaway side view of an example of the device of the present invention.

FIG. 2 is a plan view cut along the line II-II of FIG. 1;

FIG. 3 is a perspective view of a clutch drum.

[Explanation of symbols]

A Clutch Drum B Tooth C
Snap ring groove 1 Lower mold 2 Upper mold 3
Work support member 6 First slider 6a Outer end bent portion 7
Second slider 7a Bend at inner end 8 Work receiver
9 Punch 10 First cam mechanism 10a Drive cam 1
1 second cam mechanism 11a first driven cam 11b second driven cam
12 Return cam

Claims (3)

(57) [Claims] An apparatus for press-forming a snap ring groove extending in a circumferential direction at a tooth portion of an internal spline formed on a peripheral wall portion of a clutch drum, comprising: a lower die and an upper die that can move up and down. A work support member on which a clutch drum can be externally set is set up on the mold, and a first slider and a second slider slidable in the radial direction of the clutch drum are arranged vertically outside the arrangement portion of the work support member. Provided on the stage, the upper first
A work receiver that can be brought into contact with the outer peripheral surface of the clutch drum is fixed to the radially inner end of the slider, and an upwardly bent portion is formed at the radially inner end of the lower second slider. At the upper end of the part, a punch that can contact the toothed part of the internal spline is fixed, and the first slider and the second slider are respectively moved radially inward and radially outward through the cam mechanism by lowering the upper die. And forming a snap ring groove by making a punch bite into the toothed portion of the internal spline in a state where the workpiece receiver is brought into contact with the outer peripheral surface of the clutch drum. And a second cam mechanism for driving the second slider. The first cam mechanism has a first slider having a radial outer end portion of the first slider as an operation point when the upper die is lowered. Is configured to push inward in the radial direction. The second cam mechanism includes a first driven cam provided on a lower side of the second slider and pressed inward in a radial direction when the upper die is lowered, and a first driven cam provided on an outer periphery of a lower portion of the work supporting member. A second driven cam which is pushed upward by a radial inward movement of the second slider, and moves the second slider in the radial direction with the radially inner end of the second slide as an action point when the second driven cam is moved upward. A snap ring groove forming device for a clutch drum, characterized in that the device is configured to be pushed outward. 2. An upper edge of a slidable portion of a radially inner end of the second slider with respect to the second driven cam is equal to or higher than an arrangement height of the punch, and the punch bites into a toothed portion of an internal spline. 2. The snap ring groove forming device for a clutch drum according to claim 1, wherein the second driven cam is in contact with the sliding portion over the upper edge thereof in the state. 3. The first cam mechanism is constituted by a drive cam provided on an upper die, which is in contact with a radially outer end of the first slider when the upper die is lowered, and wherein the first cam mechanism has a radial direction. At the outer end, a downward bent portion is formed at the radially outer end of the second slider with a radial gap therebetween, and enters into the gap from below to form the first slider and the second slider. Urges the lower return die, which is concentric with the work supporting member, upward toward the lower die and is pushed down by the drive cam when the upper die is lowered. 3. The snap ring according to claim 1, wherein the first driven cam is pushed radially inward by the downward movement of the return cam. Groove forming device.