JP2821995B2 - 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, and the punch cannot be cut into the toothed portion of the internal spline to the required depth, thereby forming a snap ring groove. Accuracy deteriorates, and furthermore, it is necessary to extend the second slider to the outer position of the drive cam to form a bent portion at the outer end thereof, so that the outer diameter of the molding device becomes large. In view of the above, an object of the present invention is to provide a compact 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 includes a first drive cam vertically suspended from the upper die, and the lower end of the first slider is radially outer end of the first slider when the upper die is lowered. The first cam is configured to push the first slider inward in the radial direction with the portion as an action point, and the second cam mechanism is inserted into the hollow work support member so as to be vertically movable, and the upper die is lowered. A second drive cam which is pushed down, and the second drive cam is moved downward so that the radially inner end of the second slider is actuated as a second point.
The slider is configured to be pushed radially outward. In this case, the second cam mechanism is provided so as to be slidable in the radial direction through the second drive cam and a radial guide hole formed in a lower portion of the work supporting member.
A first driven cam pushed radially outward by a downward movement of the second driving cam, and a radially outward movement of the first driven cam externally vertically movably mounted on a lower outer periphery of the work supporting member. And a cylindrical second driven cam pushed up by the second slider, and the second driven cam is brought into contact with an inclined surface at a radially inner end of the second slider by upward movement of the second driven cam to move the second slider in the radial direction. It is desirable to be configured so as to be pushed outward, and downward facing the radial outer end of the first slider with a radial gap at the radial outer end of the second slider. And an annular return concentric with the work supporting member, which enters the gap from below to move the first slider and the second slider back radially outward and radially inward, respectively. A cam is urged upward on the lower die and the return cam is moved downward by the first drive cam. It is desirable to form an abutment which abuts.

[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, the second slider is extended radially inward and protrudes into the work supporting member, and the protruding end is pressed to the second drive cam so as to push the second slider radially outward. Although it is conceivable to constitute the second cam mechanism, it is necessary to provide the same number of the second sliders as the number of teeth of the internal spline. Therefore, in order to project the second slider into the work supporting member as described above, The circumferential width of the protruding end of the slider must be considerably narrowed, and the contact area of each second slider with the second drive cam becomes small, so that the surface pressure increases and the durability deteriorates.

On the other hand, when the second cam mechanism is composed of the second driving cam, the first driven cam and the second driven cam as described above, each of the first and second driven cams is provided outside the work supporting member having a margin in the circumferential direction. Since the inner end of the second slider can be brought into contact with the second driven cam, a large contact area of each of the second sliders with the second driven cam can be secured, and the first driven cam is located around the second driven cam. What is necessary is just to provide so that a push-up force may act equally at a plurality of places, and therefore the number of the first driven cams may be relatively small, and therefore, the protruding end of each of the first driven cams projecting into the work supporting member. By increasing the circumferential width, the contact area of each of the first driven cams with the second drive cam can be made large, and the durability is improved.

Further, when the upper die is raised, the first slider and the second slider
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 can be radially outwardly and radially inwardly moved by a single return cam when the upper die is raised. And the structure can be simplified. When the upper die is lowered, the return cam is pushed down by the contact of the first drive cam with the contact portion, and the first and second sliders allow the first and second sliders to move in the radial direction without interfering with the return cam. It is pushed to the outside and the outside.

The first drive cam of the present invention is provided at substantially the same position as the above-mentioned conventional drive cam, but in the present invention, the radial outer end of the second slider is extended to the outer position of the first drive cam. There is no need to extend, and the outer diameter of the molding device can be made smaller than in the conventional example.

[0011]

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 toothed portion B of an internal spline formed on a peripheral wall portion 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 for 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 that is urged upward by a spring 4a is provided on the flange portion 3a.

A cylindrical guide block 5 is provided on 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 connected to 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 equal pitches in the circumferential direction, for example, six at a pitch of 60 °. The first sliders 6 are provided at the radial inner end of the first slider 6 on the outer peripheral surface of the clutch drum A. 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 second sliders 7 are provided in the same number as the number of teeth of the internal splines, and rise up at the radially inner end of each second slider 7 in the space below the flange 3a of the work supporting member 3. Forming a bent portion 7a;
The punch 9 was attached to the upper end of the. At the tip of the punch 9, as shown in FIG.
A groove forming blade 9a, and constraint portions 9b protruding forward from both ends in the blade length direction of the groove forming blade 9a and abutting on the tooth side surfaces on both sides of the tooth ridge portion B, extending on both sides in the blade thickness direction of the groove forming blade 9a. Are formed.

The first slider 6 is pushed radially inward via the first cam mechanism 10 by the lowering of the upper die 2, and the second slider 7 is moved by the lowering of the upper die 2 to the second cam mechanism. 11 to be pushed radially outward.

In more detail, the first cam mechanism 10 includes:
The upper mold 2 is constituted by a first drive cam 10a vertically suspended one by one corresponding to each of the first sliders 6, and is formed at the lower end inner portion of the first drive cam 10a when the upper mold 2 is lowered. The slope 10b comes into contact with a slope 10c formed at the radially outer end of the first slider 6, so that the first slider 6 is pushed inward in the radial direction.

The second cam mechanism 11 slides in the radial direction through a second driving cam 11a which is inserted vertically into the work supporting member 3 and a radial guide hole 3b formed in the lower part of the work supporting member 3. It is composed of a first driven cam 11b that is freely provided, and a cylindrical second driven cam 11c that is externally movably mounted on the outer periphery of the lower part of the work supporting member 3. The second drive cam 11a is pushed down via the contact portion 11d fixed to the mold 2, and the tapered surface 11e at the lower end of the second drive cam 11a comes into contact with the slope 11f at the radial inner end of the first driven cam 11b. The first driven cam 11b is pushed radially outward, the slope 11g at the radially outer end of the first driven cam 11b abuts against the tapered surface 11h at the lower part of the second driven cam 11c, and the second driven cam 11c is moved. Pushed up and above the second driven cam 11c The tapered surface 11i each second slider 7
Each second slider 7 is brought into contact with a slope 11j at the radially inner end of
Is pushed radially outward. First driven cam 1
Four 1b are provided at a 90 ° pitch so that the second drive cam 11c can be evenly pushed up at four locations around the second drive cam 11c. The number of the first driven cams 11b may be three. In any case, the number of the first driven cams 11b is much smaller than that of the second slider 7 provided in the same number as the number of teeth of the internal spline. Since the circumferential width of the end portion can be widened, the surface pressure acting on the slope 11f at the inner end of the first driven cam 11b can be reduced. Further, since the radial inner end of the second slider 7 is located outside the work supporting member 3, a relatively large circumferential width can be ensured, and the surface pressure acting on the slope 11j at the inner end of the second slider 7 is also reduced. Not as big as left,
The durability of the second cam mechanism 11 is improved.

When the upper die 2 is raised, the second drive cam 11a is moved upward by the spring 11k and the first driven cam 11
b is returned radially inward by the spring 11l, the second driven cam 11b is returned downward, and the return cam 12 causes the first slider 6 and the second slider 7 to move radially outward, respectively. The work receiver 8 and the punch 9 are moved back inward in the radial direction, and separate from the outer peripheral surface of the clutch drum A and the tooth ridge B, respectively.

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. 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 first drive cam 10a protrudes. The return cam 12 is urged upward by cushion pins 12c as urging means provided at four places in the circumferential direction. When the upper die 2 is raised, the return cam 12 is pushed up by the urging force of the cushion pin 12c. The cam portion 12a enters the gap, and the tapered surface 12d on the inner periphery of the cam portion 12a comes into contact with the inclined surface 12e at the radially outer end of the second slider 7, so that the second portion is formed.
The slider 7 is moved inward in the radial direction and the cam portion 1 is moved.
The tapered surface 12f on the outer periphery of 2a abuts on the slope 12g at the lower end of the bent portion 6a of the first slider 6, so that the first slider 6 is moved outward in the radial direction.

The upper die 2 is provided with a work holder 13 in addition to the first drive cam 10a and the contact portion 11d. The work holder 13 is a guide bar 13 suspended from the upper mold 2.
a and is urged downward by a spring 13b. The above-mentioned springs 4a, 11k, 13
b is formed of urethane rubber.

In 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 spring 4a. It faces between the receiver 8 and the punch 9. Next, the first drive cam 10a comes into contact with the contact portion of the return cam 12, and the return cam 10a is pushed down. Further, the first drive cam 10a pushes the first slider 6 radially inward to work the workpiece. The receiver 8 comes into contact with the outer peripheral surface of the clutch drum A, and then the second driving cam 11a is pushed down, so that the first driven cam 11b and the second driven cam 11
c, the second slider 7 is pushed radially outward.

According to this, the groove forming blade 9a of the punch 9 bites into the toothed portion C of the internal spline as shown in FIGS. 1 and 5, 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 groove forming blade 9a is The snap ring groove C is accurately formed without being affected by the deflection of the slider 7 to the required depth.

Further, the flesh tends to protrude on the tooth side surface of the tooth ridge B as the groove forming blade 9a bites in. However, the flesh is prevented from protruding by the restraining portion 9b formed in the punch 9, and the burr is formed on the tooth side surface. Does not occur. By the way, when a punch is formed in a plate shape and a groove forming blade and a groove forming tooth which abuts on the tooth side surface of the tooth ridge portion B are formed at the tip thereof, and a constraint portion having an equal thickness is formed, Can be prevented, but the protrusion of the flesh to the tooth side on both sides in the blade thickness direction of the groove forming blade cannot be prevented, and the snap ring groove C is formed on the tooth side.
Burrs are formed at both edges in the groove width direction. On the other hand, in the present embodiment, since the restraining portion 9b extends on both sides in the blade thickness direction of the groove forming blade 9a, no burrs are generated on the edge.

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.

[0026]

As is apparent from the above description, according to the present invention, the snap ring groove can be formed with high precision, and the forming apparatus can be made compact.
By configuring the second cam mechanism as in the invention, the durability can be improved, and by providing the return cam as in the invention of claim 3, the structure can be simplified.

[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 punch.

FIG. 4 is an enlarged plan view of a main part showing a groove forming state.

FIG. 5 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 3b Guide hole 6 First slider 6
a bent portion at outer end 7 second slider 7a bent portion at inner end 8
Work receiver 9 Punch 10 First cam mechanism 10a
1st drive cam 11 2nd cam mechanism 11a 2nd drive cam 11
b 1st driven cam 11c 2nd 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 includes a first driving cam vertically suspended from the upper die,
When the upper mold is lowered, the first drive cam is configured to push the first slider radially inward with the radially outer end of the first slider as an action point, and the second cam mechanism is formed to be hollow. A second drive cam inserted vertically movably into the work supporting member and pushed down by a downward movement of the upper die; A snap ring groove forming device for a clutch drum, wherein the device is configured to push a slider radially outward. 2. The second cam mechanism, wherein the second cam mechanism is provided below the second drive cam so as to be slidable in a radial direction through a radial guide hole formed in a lower portion of the work supporting member. A first driven cam pushed radially outward by movement, and a cylindrical shape pushed up by a radially outward movement of the first driven cam, which is externally moved up and down on the outer periphery of a lower portion of the work supporting member. A second driven cam, and when the second driven cam is moved upward, the second driven cam is brought into contact with the inclined surface of the radially inner end of the second slider to push the second slider radially outward. 2. The apparatus according to claim 1, wherein the snap ring groove forming apparatus is configured to: 3. A downwardly bent portion is formed at a radially outer end of the first slider at a radially outer end of the second slider so as to face a radially spaced gap. The first and second sliders are moved in radially outward and radially inward, respectively, and are urged upward to the lower die by an annular return cam concentric with the work supporting member. And a contact portion formed on the return cam so as to come into contact with the first drive cam by a downward movement thereof.
Or a snap ring groove forming device for a clutch drum according to item 2.