JP2000084638A - Manufacture of drum - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drum manufacturing method in which the positional accuracy and the width accuracy of a fitting claw are improved, the assembling property is excellent, and generation of abnormal noises caused by loose coupling can be prevented. SOLUTION: In a drum manufacturing method in which a spline internal gear 2b is formed on an internal surface of a drum and a plurality of cam cut grooves 6 are formed on a circumference of a cylindrical part 2c on a drum opening end side, and a remaining part held by the cam cut grooves 6, 6 on both sides is a fitting claw 5, a drum having the internal gear provided with the spline internal gear 2b and the cylindrical part 2c is formed first, and then, a plurality of cut grooves 6 are formed on the circumference of the cylindrical part by a cutter while the spline internal gear 2b of the drum having the internal gear is a drum stopper in cutting the grooves.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a method of manufacturing a drum applied as a clutch drum of a multi-plate clutch of an automatic transmission.

[0002]

2. Description of the Related Art Conventionally, a method of manufacturing a drum having spline internal teeth and a cam cut groove, and using the remaining portion sandwiched between the cam cut grooves on both sides as a fitting claw has been performed by the following manufacturing method.

[0003] First, as shown in Fig. 7, a drum original manufactured by casting or the like is held at two positions on both sides of the outer periphery of the drum original by a holder of a groove cutting device, and is held by a cutter. Cut off the cam cut groove. Then, the groove cutting is performed at a plurality of positions on the circumference while rotating the drum original by using the index. After the completion of the groove cutting, spline internal teeth are formed on the inner surface of the original drum by tooth cutting or the like.

[0004]

However, in the conventional method of manufacturing a drum, since the holding of the drum original shape when performing the groove cutting process is performed by holding the peripheral surface having a low holding resistance to an external force, the cutter is not used. The contact force (the position where the blade edge hits) causes a shift in the pressing force, and this shift acts as a rotational force on the original drum shape as shown by the arrow in FIG. 7, and the cam cut groove cannot be cut to the design position. There was a problem.

As a result, when the remaining portion sandwiched between the cam cut grooves on both sides is fitted and coupled to the shell at the time of assembling as a fitting claw, shell coupling play occurs due to variations in the position and width of the fitting claw. It may cause abnormal noise. In addition, when the positions and widths of the fitting claws vary greatly, the fitting claws cannot be easily fitted and connected to the shell, so that a large number of assembling steps are required for actual matching, and furthermore, it becomes impossible to assemble. It is possible.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method of manufacturing a drum which can improve the positional accuracy and width accuracy of a fitting claw, and achieve good assembling properties and prevention of generation of abnormal noise due to coupling play. is there.

[0007]

Means for Solving the Problems (Solution 1) A first solution (Claim 1) of the above-mentioned problem is to dispose a plurality of spline teeth formed on the inner surface of the drum and a plurality of teeth on the circumference of the cylindrical portion on the drum opening end side. In the method of manufacturing a drum having a formed cam cut groove and a portion caught between the cam cut grooves on both sides and having a fitting claw, a drum with internal teeth having the spline internal teeth and a cylindrical portion is formed first, A plurality of cam cut grooves are formed on the periphery of the cylindrical portion by a cutter while the spline internal teeth of the drum with internal teeth are prevented from rotating around the drum during groove cutting. (Solution 2) The solution 2 of the above-mentioned problem (Claim 2) is:
2. The method for manufacturing a drum according to claim 1, wherein the internal toothed drum is formed with an internal toothed die on an outer periphery of a flow forming die set in a molding machine, and the preform material is ironed by a forming roller. It is characterized by being manufactured by flow forming molding in which it is plastically deformed so as to be poured into a mold. (Solution Means 3) Solution Means 3 (Claim 3) of the above problem is:
3. The method for manufacturing a drum according to claim 1, wherein the center of the root of the spline internal teeth, the center of the cam cut groove, the center of the root of the spline internal teeth, and the center of the fitting claw coincide with each other. The positional relationship between the cam cutting groove, the spline inner teeth, and the fitting claws is set to be the same for all.

[0008]

(Embodiment 1) Embodiment 1 corresponds to the first, second and third aspects of the present invention. [Regarding Drum Configuration] FIG. 1 is a longitudinal sectional view showing a drum manufactured by the manufacturing method of the first embodiment, FIG. 2 is a side view of a fitting portion showing the drum manufactured by the manufacturing method of the first embodiment, FIG. 3 is an enlarged view of a portion A in FIG. 2 showing the fitting claws of the drum.

As shown in FIG. 1, the drum D is composed of a boss 1 having a piston sliding surface 1a on the outer surface and a drum portion 2 having a piston sliding surface 2a and spline internal teeth 2b on the inner surface. The internal teeth 2b are formed up to an intermediate position on the end face of the drum opening, and a cylindrical portion 2c is formed from the end of the spline internal teeth 2b to the end face of the drum with the diameter of the root of the spline internal teeth 2b as the inner diameter.

The internal toothed drum having the spline internal teeth 2b and the cylindrical portion 2c is formed by forming an internal tooth mold 7a on the outer periphery of a flow forming mold 7 set in a molding machine, as described later. It is manufactured by flow forming molding in which the plastic forming 12 is plastically deformed so as to flow into the flow forming mold 7 by ironing with the outer forming roller 10.

In the drum with internal teeth, an oil hole 3, ring grooves 4a and 4b, a fitting claw 5, and a cam cut groove 6 are formed by post-processing.

A plurality of the cam cut grooves 6 are formed on the circumference of the cylindrical portion 2c on the drum opening end side, and the remaining portions between the cam cut grooves 6, 6 on both sides are used as the fitting claws 5.

The spline internal teeth 2b and the cam cut grooves 6
2 and 3, the center of the root 2b 'of the spline internal teeth 2b and the center of the cam cut groove 6 coincide (center line L1), and the root 2b of the spline internal teeth 2b, as shown in FIGS. 'And the center of the fitting claw 5 (center line L
2) The positional relationship between the spline internal teeth 2b and the cam cut groove 6 and the positional relationship between the spline internal teeth 2b and the fitting claw 5 is set to be the same for all. That is, when there is a cam cut groove 6 at one root 2b 'of the spline internal teeth 2b, there is a fitting claw 5 at the adjacent root 2b' position. On the other hand, eight cam cut grooves 6 and eight fitting claws 5 are formed.

An oil groove 2b "having a semicircular cross section is formed at the top of each spline internal tooth 2b. [Method of Manufacturing Drum] FIG. 4 shows a method of manufacturing a drum according to the first embodiment. FIG. 5 is a diagram showing a groove cutting apparatus for explaining the groove cutting processing in the drum manufacturing method according to the first embodiment.

In the method of manufacturing a drum according to the first embodiment, a drum with internal teeth having spline internal teeth 2b and a cylindrical portion 2c is first formed by flow forming, and groove cutting is performed on the spline internal teeth 2b of the drum with internal teeth. It is characterized in that the cam cut groove 6 is formed while preventing the rotation of the drum at the time.

First, the flow forming of the drum with internal teeth will be described.

The flow forming molding machine used is:
A boss press 9 and a flow forming die 7 capable of rotation and stroke are coaxially opposed to each other, and an outer forming roller 10 and an inner forming roller 11 are additionally provided.
It has. This molding machine passes through the material setting step, the boss part pressing step, the drum part flow forming step, and the boss part flow forming step, and the internal gear drum D
Is manufactured. Hereinafter, each step will be described.

In the material setting step, a disk-shaped preform material 12 having a center hole 12a is prepared in advance, and FIG.
As shown in (a), this is a step of matching the center hole 12a of the preform material 12 held by a holder (not shown) with the tip end 9a of the boss press die 9 and setting the flow forming molding machine. .

In the boss pressing step, as shown in FIG. 4B, the set preform material 12 is relatively pressed in the axial direction using the boss pressing die 9, thereby forming the center hole 12a. This is a step of forming a boss portion 1 that protrudes in the axial direction by using as a boss hole.

The drum part flow forming step includes:
As shown in FIG. 4 (c), while the blank 12 having the boss portion 1 formed by press molding is set in the molding machine, the flow forming mold 7 is axially moved with respect to the outer forming roller 10 whose axial position is fixed. Forming a drum portion 2 having a piston sliding surface 2a, spline internal teeth 2b, and a cylindrical portion 2c on an inner surface thereof by causing plastic deformation to be poured into a mold by ironing with an outer forming roller 10 while moving the material portion in the direction shown in FIG. It is.

In the boss portion flow forming step, as shown in FIG.
And the inner forming roller 11 is inserted instead, and the flow forming die 7 is moved in the axial direction toward the inner forming roller 11 so that the inner forming roller 11 causes the outer surface of the boss portion 1 to slide on the piston sliding surface 1a. This is a step of molding.

When the boss portion flow forming step is completed, the inner forming roller 11 is returned to the original position, and the molded product is released from the flow forming die 7 using a product release tool.

Next, a description will be given of a groove cutting process for forming the cam cut groove 6 on the drum with internal teeth formed by flow forming.

The groove cutting device used is a lower surface plate 1.
3, an upper surface plate 14, a die 15, a base block 16, a detent member 17, a cutter 18, and the like. The detent member 17 is provided with a detent ridge 17a at the outer peripheral position thereof, the detent ridge 17a corresponding to the tooth bottom 2b 'of the spline internal teeth 2b.

In the groove cutting process, the drum with internal teeth manufactured by flow forming is held on the inner surface, and the detent ridge 17a of the detent member 17 is fitted to the tooth bottom 2b 'of the spline internal teeth 2b. The cam cut groove 6 is cut off by the cutter 18 in this state. Then, the groove cutting process using the spline internal teeth 2b while maintaining the detent state is performed at eight positions on the circumference while rotating the drum with internal teeth by an index. [About automatic transmission to which drum manufacturing method is applied]
FIG. 5 is a cross-sectional view showing a part of a power transmission mechanism of an automatic transmission to which the drum D manufactured by the manufacturing method according to the first embodiment is applied.

In FIG. 5, 30 is an input shaft, 31 is a second shaft, 32 is a first multi-plate clutch, and D
Denotes a drum, 33 denotes a first clutch piston, 34 denotes a first clutch plate, 35 denotes a second multi-plate clutch, and 36 denotes a second clutch disc.
A clutch drum, 37 is a second clutch piston, 38 is a second clutch plate, 39 is a brake band, 40 is a shell, 41 is a sun gear, 42 is a pinion, 43 is a ring gear, and 44 is a pinion carrier.

The drum D of the first embodiment is applied as a clutch drum of a first multi-plate clutch 32 provided in an automatic transmission, and has spline internal teeth 2b of the drum portion 2.
The first clutch plate 34 is spline-fitted so as to be slidable in the axial direction, and an annular first clutch piston for applying a clutch fastening force to both piston sliding surfaces 1a, 2a of the boss portion 1 and the drum portion 2. 33 is slidably provided. Further, the second multi-plate clutch 35 and the shell 40 that covers the planetary gear are coupled to the cam cut groove 6 formed in the cylindrical portion 2c of the drum portion 2 by claw fitting. The rotation of the shaft 30 is changed from the second clutch drum 36 to the first clutch plate 3
4 → drum D → transmitted to the sun gear 41 via the shell 40.

Next, the function and effect will be described. [About the drum manufacturing method] In the drum manufacturing, when manufacturing by the procedure of groove cutting processing → spline internal tooth processing, since the holding resistance of the drum original shape against external force is low, the pressing force depends on how the cutter hits. The cam cut groove cannot be cut to a design position because the shift acts as a rotational force on the original drum shape. As a result, variations in the positions and widths of the fitting claws cause shell joint play and cause abnormal noise, and cannot be easily fitted and connected to the shell. Or even impossible to assemble.

On the other hand, in the first embodiment, a drum with internal teeth having spline internal teeth 2b and a cylindrical portion 2c is first formed by flow forming, and the spline internal teeth 2b of the drum with internal teeth are cut at the time of groove cutting. Since the drum manufacturing method in which the cam cut groove 6 is formed while the drum is stopped is adopted, the cam cut groove 6 can be cut accurately at the set position by the drum detent during the groove cutting process. The positional accuracy and the width accuracy of the fitting claw 5, which is the portion that remains between the grooves 6 and 6, are improved.

Therefore, a good assembling property that it can be easily fitted and connected to the shell 40 is secured, and the play of the connection with the shell 40 is reduced to a minimum amount corresponding to the high precision. Also, it is possible to prevent occurrence of abnormal noise, which is a collision noise due to relative rotation when the transmitted torque fluctuates. [Flow forming of drum with internal teeth]
First, with flow forming, set the material in the mold,
The material is rotated together with the mold, the forming roller is moved relatively along the mold while keeping the pressure of the forming roller against the forming part, and the material extruded by the ironing by the roller is cast while flowing into the mold. Rotation plastic working.

Therefore, when this flow forming is employed in the manufacture of the drum with internal teeth as in Embodiment 1, there is no springback in the elastic deformation region as in press molding, and the spline internal teeth 2b are formed at the same level of machining accuracy. Molding with high precision. As described above, since the accuracy of the spline internal teeth 2b is high, the spline inner teeth 2b can be sufficiently used as a detent during groove cutting, and the positional accuracy and the width accuracy of the fitting claw 5 can be secured at a high level of accuracy.

In the flow forming, the work hardening is large due to the cold plastic working, and the fiber flow phenomenon such as the landslide and the miniaturization of the crystal of the metal structure is utilized, so that the mechanical properties (tensile strength) are obtained.・ Toughness and fatigue strength)
There is also a merit that the strength is higher than the material strength. [Positional relationship between spline internal teeth and fitting structure] In the case of the conventional drum manufacturing method of groove cutting → spline internal tooth processing, the positional relationship between spline internal teeth and cam cut grooves and between spline internal teeth and fitting pawls is limited. It will fall apart for each drum. Therefore, when fitting the clutch plate to the spline internal teeth, the operation is performed while checking the position of the spline internal teeth by looking inside the drum, and it takes a great deal of time to fit the plates.

On the other hand, in the first embodiment, the center of the root 2b 'of the spline internal teeth 2b and the center of the cam cut groove 6 are matched, and the center of the root 2b' of the spline internal teeth 2b is fitted. Align the center of the nail 5 and set the spline teeth 2b
And the position of the cam cut groove 6 and the spline internal teeth 2b and the fitting claw 5 are set to be the same in all positions. The position can be recognized, and the clutch plate 34 can be easily fitted to the spline internal teeth 2b. (Other Embodiments) In the first embodiment, an example in which the present invention is applied to a clutch drum of an automatic transmission has been described. However, if the boss portion and the drum portion are integrally provided, the clutch drum of the automatic transmission may be used. Besides, the production method of the present invention can be applied.

In the first embodiment, the example in which the drum with the internal teeth is formed by flow forming has been described. However, the internal teeth of the spline may be machined before the groove cutting.

In the first embodiment, an example has been shown in which the positional relationship between the spline internal teeth and the cam cut groove and the positional relationship between the spline internal teeth and the fitting claws are all set to be the same.
Even if the positional relationship is not always the same according to the required number of spline internal teeth and the number of fitting claws, the present invention is included in the present invention.

[0036]

According to the first aspect of the present invention, there are provided spline internal teeth formed on the inner surface of the drum, and a plurality of cam cut grooves formed on the circumference of the cylindrical portion on the drum opening end side. In a method for manufacturing a drum in which a portion caught in a cam cut groove is a fitting claw, a drum with internal teeth having a spline internal tooth and a cylindrical portion is formed first, and groove cutting processing is performed on the internal spline teeth of the drum with internal teeth. Multiple cam-cut grooves are formed on the circumference of the cylindrical part by a cutter while preventing rotation of the drum at the time, thereby improving the positioning accuracy and width accuracy of the fitting claw, achieving good assemblability and preventing noise due to coupling play. The effect is obtained.

According to the second aspect of the present invention, there is provided the first aspect.
In the method for producing a drum according to the above,
An internal tooth mold is formed on the outer periphery of a flow forming mold set in a molding machine, and the preform material is manufactured by flow forming molding in which the preform material is plastically deformed so as to be poured into the flow forming mold by ironing with a forming roller. In addition to the effects of the described invention, a drum with internal teeth having high-precision spline internal teeth can be easily manufactured, and the precision of spline internal teeth used as detents at the time of groove cutting processing is high, so that fitting can be performed. The position accuracy and width accuracy of the dowel can also be secured at a high level of accuracy.

According to the third aspect of the present invention, there is provided the first aspect.
3. The method for manufacturing a drum according to claim 2, wherein the center of the root of the spline internal teeth and the center of the cam cut groove, the center of the root of the spline internal teeth and the center of the fitting claw coincide with each other, and the spline internal teeth, the cam cut groove and the spline. Since the positional relationship between the internal teeth and the fitting claws is set to be the same for all, the position of the spline internal teeth from the outside is determined by the positions of the cam cut grooves or the fitting claws in addition to the effects of the invention described in claim 1 or 2. It can be recognized, and the clutch plate and the like can be easily fitted to the spline internal teeth at the time of assembly.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a drum manufactured by a manufacturing method according to a first embodiment.

FIG. 2 is a side view of a fitting portion showing a drum manufactured by the manufacturing method according to the first embodiment.

FIG. 3 is an enlarged view of a portion A of FIG. 2 showing a fitting claw of a drum manufactured by the manufacturing method according to the first embodiment.

FIG. 4 is a diagram showing each step of flow forming molding in the drum manufacturing method according to the first embodiment.

FIG. 5 is a view showing a groove cutting device for explaining groove cutting in the drum manufacturing method according to the first embodiment;

FIG. 6 is a cross-sectional view showing a part of a power transmission mechanism of the automatic transmission to which the drum manufactured by the manufacturing method according to the first embodiment is applied.

FIG. 7 is an explanatory view of a groove cutting process in a conventional drum manufacturing method.

[Explanation of symbols]

 D Drum 1 Boss part 1a Piston sliding surface 2 Drum part 2a Piston sliding surface 2b Spline internal teeth 2c Cylindrical part 3 Oil groove 4a, 4b Ring groove 5 Fitting claw 6 Cam cut groove 7 Flow forming mold 7a Internal tooth mold 9 Boss press die 9a Tip 10 Outer forming roller 11 Inner forming roller 12 Preform material 12a Center hole 17 Detent member 18 Cutter

 ──────────────────────────────────────────────────の Continued on the front page F term (reference) 3J056 AA20 BA03 BE09 CB05 FA03 GA12 3J057 AA04 BB04 CA01 DA10 DA18 HH02 JJ04 4E087 AA08 CA12 CB03 EC13 HA37 HA82 HB02

Claims (3)

[Claims] An internal spline tooth formed on an inner surface of a drum and a plurality of cam cut grooves formed on a circumference of a cylindrical portion on an opening end side of the drum, and a portion remaining between the cam cut grooves on both sides is fitted. In the method of manufacturing a drum to be a dovetail, a drum with internal teeth having the spline internal teeth and a cylindrical portion is first formed, and the spline internal teeth of the internal toothed drum are prevented from rotating around the drum during groove cutting by a cutter. A method for manufacturing a drum, comprising forming a plurality of cam cut grooves on a circumference of a cylindrical portion. 2. The method for manufacturing a drum according to claim 1, wherein the internal toothed drum is formed on an outer periphery of a flow forming die set in a molding machine, and a preform material is formed by a forming roller. A method for manufacturing a drum, characterized by being manufactured by flow forming molding in which plastic deformation is performed so as to be poured into a flow forming mold by ironing. 3. The method of manufacturing a drum according to claim 1, wherein the center of the root of the spline internal teeth and the center of the cam cut groove, the center of the root of the spline internal teeth and the center of the fitting claw coincide with each other. Wherein the positional relationship between the spline internal teeth and the cam cut groove and the positional relationship between the spline internal teeth and the fitting claw are all set to the same relationship.