JPH10296372A - Method for forming one body type drum having inner thread and outer thread - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a forming method of one body type drum, by a short time forming, having highly precise and highly strong inner thread and outer thread while realizing to surely keep a high quality of an article, to prevent a thread from inclining, to prevent the axial enter of an inner thread and an outer thread from discrepancy and to prevent the die of outer thread from cracking, etc. SOLUTION: This is a horning method with one clamp which forms an inner thread 1a on the internal face of a 1st drum part 1 with a cold plastic deformation with a flow forming, which forms an outer thread 2a on the outer face of a 2nd drum part 2 with a cold plastic deformation with roll forming while the axial centers of a mandrel and a pressure plate are coincided and the boss part 3 of one circular meal plate is clamped and fixed with them, and on outer thread base face is formed so that the outer diameter at a wall side is smaller than at an end part side in the outer thread base face forming process as a pre-process of the rolling outer thread forming process by using an outer thread die.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention belongs to the technical field of an integrated drum forming method for forming an integrated drum having internal teeth and external teeth by a flow forming machine.

[0002]

2. Description of the Related Art Conventionally, as a drum member for fitting a clutch plate of a two-plate clutch in a transmission mechanism of an automatic transmission, for example, those shown in FIGS. 10 and 11 are known.

[0003] As shown in FIG.
The first drum on which the inner spline teeth are formed and the second drum on which the outer spline teeth are formed are manufactured by press molding, and the first and second drums are overlapped and subjected to electron beam welding (FIG. 11). This is what is integrated.

[0004]

However, in the above-mentioned conventional drum member, two independent first and second drums are manufactured, and the two drums are welded to have internal teeth and external teeth. Since the drum member is configured, there are the following problems.

(1) In manufacturing a drum member, the first
Since the press forming of the drum, the press forming of the second drum, and the electron beam welding operation of both drums must be performed, the production time is long.

(2) The first drum and the second drum are welded by an electron beam. However, after welding, it is not possible to apply a force to both drums at the manufacturing stage to check unwelded portions.
There is a possibility that a drum member having an unwelded portion may be supplied as a product, and a welding operation with great care is required to maintain high product quality.

(3) Since the first and second drums are welded by an electron beam, welding distortion caused by material heating during welding and an axis in which the axes of the first and second drums are shifted at least within a tolerance range. Misalignment is inevitable, the spline teeth are inclined by welding distortion, and the fitting gap with the clutch plate cannot be kept constant due to misalignment of the shaft.

As a result, the clutch plate fitted to the spline teeth cannot move smoothly along the spline teeth when the clutch is engaged or released, and dragging occurs.
When the clutch plate is fitted in the inclined state, the plate wear may cause uneven wear in which the plate is partially biased.

In the above description of the prior art, an example in which a drum is manufactured by press molding has been described.
As described in Japanese Patent No. 51781, flow forming has recently been known as a method for processing internal teeth with high accuracy and high strength.

[0010] Flow forming refers to cold forming in which a forming roller is pressed against a material, a rotating material is moved in an axial direction while maintaining a high pressing force, and the extruded material is poured into an inner tooth forming die inside. A method of forming internal teeth on the inner surface of a material by deformation. Therefore, teeth can be formed with high accuracy without springback in the elastic deformation region as in press molding, and fiber flow phenomena such as landslides and finer crystals of the metal structure occur, resulting in higher than material. Strength.

Therefore, assuming that a drum member having internal teeth and external teeth is constituted by using a drum having internal teeth by flow forming described in FIG. 1 of Japanese Patent Application Laid-Open No. 7-51781, Further, since a drum having external teeth is separately formed and both drums are integrated by welding, the above problem remains unsolved.

The problem to be solved by the present invention is to achieve high product quality, prevent the inclination of the teeth, prevent the axial center deviation between the internal teeth and the external teeth, and prevent the external tooth dies from cracking. It is an object of the present invention to provide a method for forming an integral drum by short-time forming having internal teeth and external teeth with high accuracy and high strength.

[0013]

[Means for Solving the Problems]

(Solution 1) Solution 1 of the above problem 1 (Claim 1)
In the integrated drum forming method for forming an integrated drum integrally including a first drum portion having internal teeth formed thereon, a second drum portion having external teeth formed thereon, and a boss portion from a single circular plate material, Forming a large-diameter internal tooth forming die, a small-diameter second drum inner surface die, and a step wall on the outer periphery of a mandrel that is a mold, sandwiching the circular plate between a mandrel and a pressure plate, A plate material fixing step of pinching and fixing the boss by aligning the axis of the plate with the plate, and a drum for preliminarily forming a portion to be the first drum portion and a portion to be the second drum portion from the rotating circular plate material Preforming step, and pressing the preformed second drum portion in the radial direction by using a pressing roller to deform the step wall to conform to the wall surface of the step wall and the shape of the inner surface of the second drum portion. Side outer diameter to end side outer diameter An external tooth base surface forming step of forming an external tooth base surface having a smaller diameter, and two forming rollers arranged opposite to each other at a rotational axis symmetric position of the mandrel, and two rollers are formed on a preformed first drum portion. And forming the internal teeth on the inner surface of the first drum portion by cold plastic deformation by flow forming in which the first drum portion is moved in the axial direction while maintaining the roller pressing. Cold plastic deformation by rolling using a backup roller that supports the external tooth dies and the pressure plate opposite to the tooth base surface at the position opposite to the external tooth dies, and moves the external tooth dies synchronized in rotation in the radial direction Rolling external teeth forming step of forming external teeth on the outer surface of the second drum portion.

(Solution 2) Solution 2 of the above problem 2
According to a second aspect of the present invention, in the method of forming an integral drum having the internal teeth and the external teeth according to the first aspect, the pressing roller used in the external tooth base surface forming step is a taper pressing roller, so that the wall side is edged. It is characterized in that an external tooth base surface having a smaller diameter than the part side is formed.

(Solution 3) Solution 3 of Problem 3
(Claim 3) is the internal tooth of claim 1 or claim 2.
In the integrated drum forming method having external teeth, the step wall is an intermediate step wall having a step surface smaller in diameter than the internal tooth forming die and larger in diameter than the inner surface mold of the second drum portion, and a mandrel is provided on the outer periphery of the pressure plate. Forming an axially protruding portion inner surface mold having the same outer diameter as the second drum portion inner surface mold, and in the external tooth base surface forming step, using a pressing roller, radially move the preformed second drum portion to be the second drum portion The axial protrusion protrudes outward from the boss by being pressed to crush the gap, and deformed to conform to the shape of the inner diameter side wall surface of the intermediate step wall, the inner surface of the second drum portion, and the shape of the inner surface of the axial protrusion. And forming an external tooth base surface having the following.

(Solution 4) Solution 4 of the above-mentioned problem 4
(Claim 4) is an internal tooth according to claims 1 to 3.
In the integrated drum forming method having external teeth, the processing of each of the above-described steps is performed in the order of a plate material fixing step, a drum part preforming step, an external tooth base surface forming step, a rolling external tooth forming step, and a flow forming internal tooth forming step. It is characterized by performing.

(Solution 5) Solution 5 of the above problem 5
(Claim 5) is the internal tooth of claim 1 to claim 4.
In the integral drum forming method having external teeth, the internal teeth are spline teeth, the external teeth are involute teeth, and the formed integral drum is used as spline teeth and involute teeth of clutch plates of two multi-plate clutches, respectively. The present invention is characterized in that it is applied as a drum member provided in a transmission mechanism of a fitted automatic transmission.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) The embodiment 1 is defined as claims 1 to 5
An integrated drum molding method having internal teeth and external teeth corresponding to the described invention.

First, the structure of the integrated drum will be described.

FIG. 1 is a sectional view showing an integrated drum having internal teeth and external teeth formed by the method of forming an integrated drum having internal teeth and external teeth according to the first embodiment. FIG. FIG. 3 is a view showing teeth of an integrated drum, and FIG. 4 is an automatic drum to which an integrated drum formed by an integrated drum forming method having internal teeth and external teeth according to the first embodiment is applied. FIG. 3 is a cross-sectional view illustrating a transmission mechanism of the transmission.

As shown in FIG. 1, the integrated drum A is formed by using a single circular plate as a raw material. The first drum portion 1 on which the spline internal teeth 1a are formed and the involute external teeth 2a are formed. The second drum portion 2 is formed integrally with a boss portion 3 extending radially from the second drum portion 2, and an intermediate portion is provided between the first drum portion 1 and the second drum portion 2. A step portion 4 is set.

As shown in FIG. 2, the spline internal teeth 1a are formed with a plurality of trapezoidal teeth at equal intervals, and the involute external teeth 2a are formed as involute teeth as shown in FIG. A plurality are formed at intervals.

As shown in FIG. 3, the integrated drum A is applied as a high clutch drum provided in a transmission mechanism of an automatic transmission.

In FIG. 3, 5 is an input shaft, 6 is an oil pump cover, 7 is a reverse clutch drum connected to a sun gear of a front planetary gear (not shown), and A is a high clutch drum connected to the input shaft 5. 8 is a band brake that is engaged in the second and fourth forward speeds, 9 is a reverse clutch (multi-plate clutch) that is engaged in the reverse stage, and 10 is a high clutch that is engaged in the third and fourth forward speeds (Multi-plate clutch), 11 is a reverse clutch piston, and 12 is a high clutch piston.

The driven plate 10a of the high clutch 10 is fitted to the spline internal teeth 1a of the integrated drum A, and the involute external teeth 2a of the integrated drum A are
The drive plate 9a of the reverse clutch 9 is fitted.

Next, the structure of the integrated drum molding machine will be described.

FIG. 5 is a schematic front view showing an integrated drum forming machine used in the integrated drum forming method according to the first embodiment.

In FIG. 5, 20 is a machine frame, 21 and 22 are swing arms, 23 and 24 are arm guides, 25 is a bending roller support slide base, 26 and 27 are roller support slide bases, 28 is a material bending roller, 29 is a forming roller, 30 is a backup roller, 31 is an external tooth die, 32 is a pressing and forming roller, and 33 is a mandrel.

The pressing and forming roller 32 is a dual-purpose roller having a pressing roller portion and a forming roller portion. The pressing roller portion is formed as a taper pressing roller portion having a tapered surface.

The mandrel 33 performs a rotating operation and a sliding operation of moving while maintaining the rotation axis.
It is fixed to the forming shaft 34 and is disposed at a position surrounded by the material bending roller 28, the forming roller 29, the backup roller 30, the external tooth die 31, and the pressing and forming roller 32.

The rollers and the like used in each process are as follows:
By the swing operation by the swing arms 21 and 22 and the slide operation by the support slide bases 25, 26, and 27, the arrangement and replacement are performed as needed, and the amount of radial movement of the roller is also given.

Next, a method of forming an integrated drum having internal teeth and external teeth will be described.

Prior to the description of the integral drum molding method, the structure of the molding material clamp will be described with reference to FIG.

The outer diameter of the mandrel 33 is set to be larger than the outer diameter of the pressure plate 36, and is fixed to a first forming shaft 34 via a die-cutting ring member 35.
On its outer periphery, an inner tooth forming die 33a is formed in a large diameter part, and a second drum part inner surface die 33b is formed in a small diameter part having the same diameter as the outer diameter of the pressure plate 36. An intermediate step wall 33c is formed between the inner mold 33b and the drum portion.

The pressure plate 36 is fixed to a second shaping shaft 38 via a synchronous gear 37, and has an inner surface die 36a of the second drum portion 2 in the axial direction on the outer periphery thereof.

Further, centering projections 3 fitted to each other are provided at the ends of the mandrel 33 and the pressure plate 36.
3d and a centering recess 36b are formed.

The integral drum A is formed by a plate material fixing process.
It is performed in the order of the drum part preforming step, the external tooth base surface forming step, the rolling external tooth forming step, and the flow forming internal tooth forming step. Hereinafter, each step will be described separately.

[Sheet fixing step] In the sheet fixing step, FIG.
As shown in a portion below the axis O of FIG. 2, a circular plate material A ′ whose outer peripheral portion is slightly bent to the mandrel 33 side is formed into a mandrel 33 having an internal tooth forming die 33 a on the outer periphery and an outer peripheral surface of the second drum portion 2. The boss portion 3 is sandwiched and fixed between the pressure plate 36 serving as the inner surface mold 36a of the axially projecting portion, the mandrel 33 and the axis O of the pressure plate 36 being aligned.

In this plate material fixing step, the centering convex portion 33d and the centering concave portion 36b are fitted to make the axis O of the mandrel 33 and the pressure plate 36 coincide with each other. The shape of the part 3 is used.

[Drum Part Preforming Step] In the drum part preforming step, as shown in the portion above the axis O in FIG.
Using the material bending roller 28, the rotating circular plate material A '
Is bent toward the mandrel 33, and a portion to be the first drum portion 1 and a portion to be the second drum portion 2 are preliminarily formed.

[External Tooth Base Surface Forming Step] In the external tooth base surface forming step, as shown in FIG. 7, a preformed second drum portion 2 is formed in a radial direction by using a pressing and forming roller 32. The gap is crushed by pressing, and is deformed in accordance with the shape of the inner diameter side wall surface of the intermediate step wall 33c, the shape of the second drum portion inner surface die 33b, and the shape of the axially projecting portion inner surface die 36a, thereby protruding outward from the boss portion 3. An external tooth base surface having an axial projection is formed.

In this step, as shown in the enlarged view of the portion C in FIG. 7, the pressing roller portion of the pressing and forming roller 32 is formed of a tapered surface having a taper angle α with a larger roller outer diameter on the wall side. Therefore, the outer tooth base surface of the molding material has a smaller outer diameter on the wall side than the outer diameter on the end side.

[Rolled External Teeth Forming Step] In the rolled external tooth forming step, as shown in FIG. 8, the external tooth dies 31 and the pressure plate 36 arranged opposite to the external tooth base surface are placed opposite to the external tooth dies 31. Using the backup roller 30 which is supported at the position, the externally toothed dies 31 which are rotationally synchronized are radially centered on the axis O.
The outer teeth 2a are formed on the outer surface of the second drum portion 2 by cold plastic deformation due to rolling which is moved toward.

Here, the rotation synchronization of the external tooth dies 31 is achieved by providing the external tooth dies 31 on a rotary shaft 40 provided with a synchronous gear 39 meshing with the synchronous gear 37.

In the rolling external tooth forming step, the external tooth dies 31 are formed.
When the is moved toward the axis O in the radial direction, the molding material flows to the wall side and the end side due to plastic deformation, and the external tooth base surface is an axially parallel cylindrical surface in the external tooth base surface forming step. in case of,
There is no relief for the molding material flowing to the wall side due to the flow molding, so that a large load is applied to the external tooth dies 31 and there is a concern that the external tooth dies 31 may be cracked. Is formed as a tapered surface having a smaller diameter than the outer diameter on the end side, so that the tapered recess formed by the tapered surface flows toward the wall by the flow molding as shown in the enlarged view of the portion D in FIG. And the load on the external tooth dies 31 is reduced to prevent die cracks and increase the flowability of the molding material.

[Flow Forming Internal Tooth Forming Step] As shown in FIG. 9, the flow forming internal tooth forming step includes forming roller 29 and pressing / forming roller 3 which are arranged to face each other at a rotational axis symmetric position of mandrel 33.
2, two rollers 29, 32 are pressed against the preformed first drum unit 1 (shown in FIG. 8) from the end position,
Internal teeth 1a are formed on the inner surface of the first drum unit 1 by cold plastic deformation by flow forming in which the first drum unit 1 is moved in the axial direction while maintaining the roller pressing.

That is, the deformation of the plate becomes plastic deformation flowing into the internal tooth forming die 33a due to the movement while maintaining the roller pressing, and the internal teeth 1a are formed on the inner surface of the first drum portion 1 as the internal tooth forming die 33a. Is done. At this time, there is an overflow in which the plate material flows in the moving direction and a back flow in which the plate material flows in the direction of the second drum portion 2. The overflow portion is cut off by post-processing, and the back flow portion is cut off by the intermediate step portion 4. 2a is absorbed without overlapping.

Next, the effects will be described.

(1) A first drum portion 1 having internal teeth 1a formed thereon and a second drum having external teeth 2a formed from one circular plate material A '.
In an integrated drum forming method having an internal tooth and an external tooth for forming an integrated drum A integrally having a drum portion 2 and a boss portion 3, a circular plate material A is formed by aligning the axes O of a mandrel 33 and a pressure plate 36. The external teeth 2a are formed on the outer surface of the second drum portion 2 by cold plastic deformation by rolling while the boss portion 3 of the ′ ′ is fixed by pinching, and the first drum portion 1 is formed by cold plastic deformation by flow forming. In the method of forming the internal teeth 1a on the inner surface, and in the external tooth base surface forming step which is a pre-process of the rolled external tooth forming step using the external tooth dies 31, the outer diameter of the wall side is changed to the outer side of the end side. Since the external tooth base surface having a diameter smaller than the diameter is formed, high product quality is ensured, the inclination of the teeth is prevented, and the axial center of the internal teeth 1a and the external teeth 2a is prevented from shifting.
It is possible to provide a method of forming the integrated drum A by short-time forming having the high-precision and high-strength internal teeth 1a and the external teeth 2a while preventing the external tooth dies 31 from cracking.

That is, instead of integrating two drums having internal teeth and external teeth by welding as in the prior art, a method of processing an integrated drum A having external teeth 2a and internal teeth 1a with one clamp. Therefore, the problems caused by welding are eliminated, high product quality is ensured, tooth inclination is prevented,
It is possible to prevent the axial deviation of the internal teeth 1a and the external teeth 2a,
By the simultaneous molding, the integrated drum A can be manufactured in a short time.

Further, since both the inner teeth 1a and the outer teeth 2a are formed by cold plastic deformation, a highly accurate and high-strength tooth surface can be obtained.

(2) The external tooth base surface whose wall side is smaller than the end side is formed by using a taper pressing roller portion as the pressing roller portion of the pressing and forming roller 32 used in the external tooth base surface forming step. As a result, not only the load on the external tooth dies 31 is reduced to prevent die cracking, but also the tapered recess formed by the tapered surface serves as a relief for the molded material flowing toward the wall side by the flow molding, thereby increasing the fluidity of the molded material. .

(3) The step wall is an intermediate step wall 33c having a smaller diameter than the internal tooth forming die 33a and a step surface having a larger diameter than the second drum inner surface die 33b, and the second mandrel 33 on the outer periphery of the pressure plate 36. An axially projecting portion inner surface mold 36a having the same outer diameter as the drum portion inner surface mold 33b is formed. In the external tooth base surface forming step, a part to be the preformed second drum portion 2 is formed by using a pressing and forming roller 32. By pressing in the radial direction, the gap is crushed, and the intermediate step wall 33c is pressed.
The outer tooth base surface having the axially projecting portion projecting outside the boss portion 3 is formed by deforming according to the shapes of the inner diameter side wall surface, the second drum portion inner surface die 33b and the axially projecting portion inner surface die 36a. Due to this method, when the external tooth dies 31 are pushed into the external tooth base surface, a flow pattern is created in which excess material due to plastic deformation flows to the axial protrusion, and the external teeth can be formed in an orderly manner. Dimensional control of the axial protrusion amount after the external teeth are formed can also be performed.

(4) Since each of the processes is performed in the order of the plate material fixing process → the drum portion preforming process → the external tooth base surface forming process → the rolled external tooth forming process → the flow forming internal tooth forming process, When the external teeth 2a are formed by molding, the inclination of the external teeth 2a caused by the axial offset positional relationship between the external tooth dies 31 and the backup roller 30 causes the internal teeth 1a.
Is modified by flow forming to form
As compared with the case where the external teeth 2a are formed after the formation of the external teeth 2a, the highly accurate external teeth 2a in which the meshing axis coincides with the rotation axis can be obtained.

(5) The internal teeth are the spline internal teeth 1a, the external teeth are the involute external teeth 2a, and the formed integral drum A is used as the plates 9a, 10 of the two clutches 9, 10.
a is applied as a high clutch drum provided in a transmission mechanism of an automatic transmission fitted to the spline internal teeth 1a and the involute external teeth 2a, respectively.
a can be smoothly moved along the internal teeth 1a and the external teeth 2a when the clutches 9, 10 are engaged or released, without the plates 9a, 10a being fitted to be inclined. Wear is prevented and the clutch 9,
10 can improve the durability reliability.

(Other Embodiments) In the first embodiment, an example is shown in which the formed integral drum is applied as a drum member provided in a transmission mechanism of an automatic transmission. Can be applied as a speed change mechanism,
Furthermore, the present invention is also applicable to a gear in which the internal teeth and the external teeth are gear teeth, the internal gears are one sun gear and the external teeth are the other ring gear in two adjacent planetary gear sets, and both gears are connected by a rotating member. can do.

In the first embodiment, an example is shown in which the rolling external tooth forming step is performed in the order of the flow forming internal tooth forming step. Conversely, the flow forming internal tooth forming step is performed in the order of the rolling external tooth forming step. You may do it.

In the first embodiment, the example in which the second drum portion and the boss portion are T-shaped has been described. However, the second drum portion has an inverted L-shape in which the second drum portion extends in the axial direction from the end position of the boss portion. Is also good.

In the first embodiment, an example is shown in which the tapered roller is used to form the external tooth base surface with the wall side smaller than the end side. However, the flowability of the molding material is somewhat inferior, but the stepped roller is used to form the wall side. An example in which the external tooth base surface having a smaller diameter than the end side may be formed.

[0060]

According to the first aspect of the present invention, the first drum portion having the internal teeth formed from a single circular plate material, the second drum portion having the external teeth formed thereon, and the boss portion are integrally formed. In an integrated drum forming method having internal teeth and external teeth for forming an integrated drum, as described in claim 1, the boss portion of the circular plate material is pinched and fixed by matching the axes of the mandrel and the pressure plate. The method of forming external teeth on the inner surface of the first drum part by cold plastic deformation by flow forming and forming the external teeth on the outer surface of the second drum part by cold plastic deformation by rolling, that is, In the method of processing the teeth and the internal teeth by one clamp, and in the external tooth base surface forming step which is the pre-process of the rolled external tooth forming step using the external tooth dies, the outer diameter of the wall side is the end side. External tooth base surface smaller than outer diameter is formed High precision and high strength internal and external teeth, while ensuring high product quality, preventing tooth inclination, preventing axial deviation between internal and external teeth, and preventing external tooth dies from cracking. A method for forming an integrated drum by short-time molding can be provided.

According to the second aspect of the present invention, the first aspect is provided.
In the integrated drum forming method having the internal teeth and the external teeth according to the above, the external tooth base surface having a smaller diameter than the end side by making the pressing roller used in the external tooth base surface forming step a taper pressing roller. Due to the molding, in addition to the above-described effects, the tapered concave portion formed by the tapered surface serves as a relief for the molded material flowing toward the wall side by the flow molding, and the fluidity of the molded material can be increased.

According to the third aspect of the present invention, there is provided the first aspect.
Or in the integral drum forming method having internal teeth and external teeth according to claim 2, the step wall is an intermediate step wall having a step surface smaller in diameter than the internal tooth forming die and larger in diameter than the second drum part inner surface type, An axially projecting portion inner surface mold having the same outer diameter as the second drum portion inner surface mold of the mandrel is formed on the outer periphery of the pressure plate. In the external tooth base surface forming step, a pressing roller is used.
The gap is crushed by pressing the preformed second drum portion in the radial direction to fit the shape of the inner side wall surface of the intermediate step wall, the inner surface of the second drum portion, and the inner surface of the axial protrusion portion. Since the external tooth base surface having the axial projection protruding outward from the boss portion by deforming is formed, in addition to the effect of claim 2, when the external tooth die is pushed into the external tooth base surface, A flow pattern is created in which excess material due to plastic deformation flows to the axial projection, so that the external teeth can be formed neatly and the dimension of the axial projection after the external teeth are formed can be controlled.

In the invention according to claim 4, claim 1
In the integrated drum forming method having internal teeth and external teeth according to claim 3, the processing of each step is performed by a plate material fixing step → a drum part preforming step → an external tooth base surface forming step → a rolled external tooth forming step → Since the method is performed in the order of the flow forming internal tooth forming step, in addition to the above-described effects, the inclination of the external teeth caused by the axial offset positional relationship between the external tooth dies and the backup roller at the time of forming the external teeth by rolling reduces the internal teeth. It is possible to obtain the external teeth which are corrected by the flow forming to be formed and have higher meshing shaft accuracy than the case where the external teeth are formed after forming the internal teeth first.

In the invention according to claim 5, claim 1 is
The method of forming an integral drum having internal and external teeth according to claim 4, wherein the internal teeth are spline teeth, the external teeth are involute teeth, and the formed integral drum is a clutch plate of two multi-plate clutches. Since the present invention is applied as a drum member provided in a transmission mechanism of an automatic transmission fitted to spline teeth and involute teeth, in addition to the above effects, the clutch plates fitted to the internal teeth and the external teeth are set to be inclined. In addition, when the multi-plate clutch is engaged or released, the multi-plate clutch can move smoothly along the internal teeth and the external teeth, preventing clutch drag and uneven wear of the clutch plate, and improving the durability reliability of the multi-plate clutch.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an integrated drum having internal teeth and external teeth formed by an integrated drum forming method having internal teeth and external teeth according to a first embodiment.

FIG. 2 is a view showing internal teeth of an integrated drum.

FIG. 3 is a view showing external teeth of an integrated drum.

FIG. 4 is a cross-sectional view showing a transmission mechanism of an automatic transmission to which an integrated drum formed by an integrated drum forming method having internal teeth and external teeth according to Embodiment 1 is applied.

FIG. 5 is a schematic front view showing an integrated drum forming machine used in the integrated drum forming method according to the first embodiment.

FIG. 6 is a process explanatory diagram of a plate material fixing step and a drum part preforming step of the integrated drum forming method according to the first embodiment.

FIG. 7 is an explanatory diagram of an external tooth base surface forming step of the integral drum forming method according to the first embodiment.

FIG. 8 is an explanatory diagram of a rolling external tooth forming step of the integral drum forming method according to the first embodiment.

FIG. 9 is an explanatory diagram of a flow forming internal tooth forming step of the integral drum forming method according to the first embodiment.

FIG. 10 is a sectional view showing a drum member for an automatic transmission according to a conventional molding method.

FIG. 11 is an enlarged sectional view showing an electron beam welded portion (part B in FIG. 10) of a drum member for an automatic transmission according to a conventional molding method.

[Explanation of symbols]

 A 'Circular plate material A Integrated drum 1 First drum part 1a Internal teeth 2 Second drum part 2a External teeth 3 Hub 9 Reverse clutch (multi-plate clutch) 10 High clutch (multi-plate clutch) 28 Material bending roller 29 Forming roller Reference Signs List 30 backup roller 31 external tooth die 32 pressing and forming roller 33 mandrel 36 pressure plate

Claims (5)

[Claims] 1. An integrated drum forming method for forming an integrated drum integrally including a first drum portion having internal teeth formed thereon, a second drum portion having external teeth formed thereon, and a boss portion from a single circular plate material. Forming a large-diameter internal tooth forming die, a small-diameter second drum inner surface die, and a step wall on the outer periphery of a mandrel that is a forming die, and sandwiching the circular plate material between the mandrel and the pressure plate; A plate material fixing step in which the mandrel and the pressure plate are axially aligned and the boss portion is clamped and fixed, and a portion serving as the first drum portion and a portion serving as the second drum portion are preliminarily formed from the rotating circular plate material. The preforming step of the drum part to be formed, and pressing the part to be the preformed second drum part in the radial direction by using a pressing roller, thereby deforming according to the shape of the wall surface of the stepped wall and the inner surface of the second drum part. Let the outer diameter of the wall side An external tooth base surface forming step of forming an external tooth base surface having a diameter smaller than the outer diameter of the part side; and a first drum preformed using two forming rollers arranged to face each other at a rotational axis symmetric position of the mandrel. Flow forming internal teeth forming to form internal teeth on the inner surface of the first drum part by cold plastic deformation by flow forming in which two rollers are pressed against the part and the first drum part is moved in the axial direction while maintaining roller pressing A step of rolling the external tooth dies, which are rotationally synchronized with each other in the radial direction, using a backup roller that supports the external tooth dies and the pressure plate at a position opposite to the external tooth dies, the external tooth dies being opposed to the external tooth base surface. Forming an external tooth on the outer surface of the second drum portion by cold plastic deformation by a rolled external tooth forming step, wherein the integrated drum having internal teeth and external teeth is provided. Method. 2. The method of forming an integral drum having internal teeth and external teeth according to claim 1, wherein the pressing roller used in the external tooth base surface forming step is a taper pressing roller, so that the wall side is the end side. An integrated drum forming method having internal teeth and external teeth, characterized by forming an external tooth base surface having a smaller diameter. 3. The method of forming an integral drum having internal teeth and external teeth according to claim 1 or 2, wherein the step wall has a diameter smaller than that of an internal tooth forming die and larger than that of a second drum part inner surface die. An intermediate step wall having a step surface, an inner surface mold of an axially protruding portion having the same outer diameter as the inner surface mold of the second drum portion of the mandrel is formed on the outer periphery of the pressure plate, and in the outer tooth base surface forming step, a pressing roller is formed. The gap is crushed by radially pressing the preformed second drum portion to be used to form the inner wall surface of the intermediate step wall, the inner surface of the second drum portion, and the inner surface of the axial protrusion portion. An integrated drum forming method having internal teeth and external teeth, wherein an external tooth base surface having an axial projection protruding outward from the boss is formed by deforming together. 4. The method for forming an integrated drum having internal teeth and external teeth according to claim 1, wherein the processing in each of the steps comprises: a plate material fixing step → a drum part preforming step → external tooth base surface forming. An integrated drum forming method having internal teeth and external teeth, which is performed in the order of a step, a rolling external tooth forming step, and a flow forming internal tooth forming step. 5. The integrated drum forming method according to claim 1, wherein the internal teeth are spline teeth, and the external teeth are involute teeth. Wherein the clutch plate of the two multi-plate clutches is applied as a drum member provided in a transmission mechanism of an automatic transmission in which the clutch plates are fitted to spline teeth and involute teeth, respectively. Method.