JP2869871B2 - Cylindrical housing for multi-plate clutch and molding method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Objects of the Invention (1) Field of the Invention The present invention relates to a cylindrical housing for a multi-plate clutch and a method of forming the same.

(2) Prior art The applicant of the present application has previously described, as a housing of this type,
As described in JP-A-64-35123, a product formed through drawing and ironing has been developed.

10, as shown in FIG. 11, the housing 1 ₀ includes a cylindrical body 3, provided with an end wall 5 connected to one end of the cylindrical body 3, the inner peripheral surface of the cylindrical body 3, a plurality of driving clutch A spline Sp that slidably fits the plate, and a circlip mounting groove 14 arranged in a ring across the tooth surface of the spline Sp. A protrusion 39 is provided in a region corresponding to 12, and a recess 40 is provided in a region corresponding to each spline tooth 13.

The reason for forming this way the respective spline grooves 12 and spline teeth 13 is projected to the cylindrical body 3 alternately radially inwardly and outwardly, the housing 1 ₀ by using a thin steel plate having a plate thickness of the blank This is to reduce the weight of the device.

According to the housing 1 _0, by increasing the contact area between the driving clutch plates and the splined Sp enables high torque transmission and in which the sliding of the driving clutch plate can be smoothly performed.

(3) In accordance problem however to be Solved, it was added various investigations on the housing 1 _0, since each concave 40 resides in correspondence with the spline teeth 13, the thickness of each spline tooth 13 becomes thin and 11 when chamfering the race processing or the like to the opening outer circumferential edge of the housing 1 ₀ as shown in FIG line e, Kakutotsujo 39 and each ridge 39 due to the outer diameter difference of each concave 40 The amount of cutting increases,
As a result, it was found that the strength around each mounting groove 14 tends to decrease.

In this case, in order to improve the strength around each mounting groove 14, a blank may be formed from a thick steel plate and the outer peripheral surface of the cylindrical body 3 may be formed as a cylindrical surface. and the at the reference will not be able to comply the demand for weight reduction for the weight of the housing 1 ₀ is increased (the publication, reference Fig. 10).

In view of the above, an object of the present invention is to provide the housing and a method of molding the housing, which can improve the strength around each mounting groove without impairing the weight reduction.

B. Configuration of the Invention (1) Means for Solving the Problems The present invention includes a cylinder and an end wall connected to one end of the cylinder, and a plurality of drive clutch plates are provided on an inner peripheral surface of the cylinder. A multi-plate clutch cylindrical housing having a circlip mounting groove arranged in a ring across the spline of the spline and slidably fitted to the spline. An area including a portion corresponding to the mounting groove is formed on the cylindrical surface from the end face of the opening of the cylindrical body, and each spline tooth is formed on the outer peripheral surface of the cylindrical body from the cylindrical surface to the end wall. Are provided, and the bottom surface of each recess and the cylindrical surface are smoothly continued.

A method of forming a tubular housing for a multi-plate clutch according to the present invention includes a tubular portion and an end wall connected to one end of the tubular portion, and slides a plurality of drive clutch plates on the inner peripheral surface of the tubular portion. By subjecting a blank to drawing processing, an intermediate body roughly formed with a spline groove of a spline that fits freely and a spline tooth that forms a mounting groove for a circlip arranged in a ring across the tooth surface is drawn into a blank. By forming, then, by positioning the end wall on the front side in the processing direction and performing ironing on the cylindrical portion, a cylindrical body having the spline grooves and spline teeth of complete accuracy on the inner peripheral surface, and the cylindrical body An end wall present at one end is formed, and at the same time, a region including a portion corresponding to the mounting groove from the end surface of the opening of the cylindrical body is formed into a cylindrical surface on the outer peripheral surface of the cylindrical body, and the end wall is formed from the cylindrical surface. Area leading to Corresponding to each spline teeth, and characterized by forming a recess smoothly by continuous bottom to the cylindrical surface.

(2) Operation When the cylindrical surface is formed on the outer peripheral surface of the housing as described above, the decrease in the thickness of each spline tooth due to the mounting groove can be minimized, and the chamfering of the outer peripheral edge of the opening of the housing is performed. Can be performed uniformly over the entire circumference. Thereby, the strength around each mounting groove can be improved.

Further, since concave portions are formed on the outer peripheral surface of the housing corresponding to the spline teeth, the weight of the housing can be reduced by these concave portions. In addition, since the bottom surface of each concave portion is smoothly continuous with the cylindrical surface, there is no stress concentration portion between the cylindrical surface and each concave portion, thereby improving the durability of the housing.

In the above forming method, when drawing and ironing are performed, each spline groove, each spline tooth, a cylindrical surface, and each concave portion are formed with high precision by the cooperation of the punch and the die without causing the fiber flow to be cut. The obtained high strength housing can be obtained efficiently.

(3) Embodiment FIG. 1 shows a multiple disc clutch C provided with a tubular housing 1 obtained according to the present invention.

The housing 1 which is rotated by the drive shaft 2 includes a cylindrical body 3 having a small diameter cylinder 3 ₂ provided continuously to the larger-diameter tubular 3 ₁ and its larger-diameter tubular 3 ₁ of the other end having an opening at one end, a small diameter tube 3 _{And an} annular end wall 5 connected to one end of the end wall ₂ .
The boss 6 which is spline-fitted to the drive shaft 2 is welded so as to protrude inward.

Disc-shaped piston 7 between the boss 6 outer peripheral surface and a small-diameter tube 3 _second inner peripheral surface is slidably fitted in the hydraulic chamber 8 is defined between that piston 7 and the end wall 5. An oil passage 9 communicating with the hydraulic chamber 8 is formed in the boss 6.
Are linked.

The inner peripheral surface of the large diameter cylinder 3 _1, spline Sp fitting the driving clutch plate 11 slidably is formed. In the larger-diameter tubular 3 ₁ of the opening inner surface, spline teeth between Aitonaru splines 12
A circlip mounting groove 14 is formed in the annular groove 13 across the tooth tip surface, and a circlip 15 is mounted in the mounting groove 14. Spline Sp on the inner surface of circlip 15
The driven clutch plates 17 are interposed between the end plates 16 and the driving clutch plates 11 and between the adjacent driving clutch plates 11, respectively, and each driven clutch plate 17 is driven. A member 18 is slidably fitted to a spline 19. G is a gear fitted to the driven member 18.

In the above configuration, when hydraulic pressure is supplied to the hydraulic chamber 8, the piston 7 advances by the hydraulic pressure, the drive clutch plate 11 is pressed against the driven clutch plate 17, and the clutch C is connected.
As a result, power is transmitted from the drive shaft 2 to the driven member 18. On the other hand, when the supply of the hydraulic pressure to the hydraulic chamber 8 is released, the piston 7 retreats due to the elastic force of the return spring 10 and the clutch C
Is cut off, whereby the power transmission is released.

2 to 4 show the housing 1 before the boss mounting hole 5a is formed. The housing 1 is rough drawn by a cooperation of a punch and a die using a circular blank having a small plate thickness, drawn and processed. It is formed by continuously performing ironing.

In the outer peripheral surface of the large diameter cylinder 3 _1, area a ₁ including a portion corresponding to the mounting groove 14 from the opening end face 3a is formed on the outer diameter is equal cylindrical surface b.

Also in the region a ₂ leading to annular end wall 5 from the cylindrical surface b, recesses 20 corresponding to the land portions 13 are formed. The bottom surface c and the cylindrical surface b of each recess 20 are smoothly continued via the slope d.

When the above method is adopted, each spline groove 12, each spline tooth 13, without causing the fiber flow to be cut.
The high strength housing 1 in which the cylindrical surface b and each recess 20 are formed with high precision can be obtained efficiently.

In the housing 1, when forming the large-diameter cylinder 3 ₁ outer peripheral surface the cylindrical surface b as described above, it is possible to minimize the decrease wall thickness of the spline teeth 13 by the mounting groove 14, also large the chamfer for opening outer periphery of the cylinder 3 ₁ can be uniformly performed to the outer peripheral edge of such diameter over its entire circumference, as shown in FIG. 4 line e. Thereby, the strength around each mounting groove 14 can be improved.

Furthermore the large-diameter tubular 3 ₁ outer circumference, since the concave portion 20 corresponding to the spline teeth 13 are formed, lightweight housing 1 is achieved by the recesses 20. In addition, since the bottom surface c of each recess 20 is smoothly continuous with the cylindrical surface b via the slope d, there is no stress concentration point between the cylindrical surface b and each recess 20, thereby improving the durability of the housing 1. Can be done.

The end face f of spline grooves 12 in the small diameter cylinder 3 ₂ side as best shown in Figure 4 has a substantially right angle with respect to the small diameter cylinder 3 _second inner peripheral surface, the spline grooves 12 and spline teeth 13 rolling When formed by processing, the end face f of each spline groove 12 forms an arc surface as shown in FIG. 4A, and the end face f and the small diameter portion
Since 3 and inner ₂ peripheral surface is continuously provided via an extension g of the arcuate surface, in order to ensure the operation stroke h of the piston 7 the axial length of the housing 1 ₁ in response to the extension portion g k
Must be as long, but the result the housing 1 ₁ is large, the size of the problem in the housing 1 according to the present invention has been solved.

5 and 6 show a molding apparatus for obtaining the housing 1, and FIG. 5 shows an upper mold 21 and a lower mold 22 before the start of molding.
Fig. 6 shows the relationship between the two dies 21 and 2
The relationship of 2 is shown respectively. The molding apparatus is drawn so as to correspond to the cross section of the housing 1 in FIG.
22 is configured to be able to move up and down with respect to the fixed upper mold 21.

The upper die 21 includes an upper holder 23, a punch 24 held by the upper holder 23, and a blank positioning rod 25 serving also as a knockout rod attached to the upper holder 23 so as to penetrate the center of the punch 24. The fitting projection 25a at the lower end of the positioning rod 25 projects from the lower end surface of the punch 24. Punch 24 is convex shaping the large diameter portion 24a corresponding to the large-diameter cylinder 3 _1, and a small diameter portion 24b corresponding to the small diameter portion 3 _2, the spline grooves 12 on the outer peripheral surface of the large diameter portion 24a A ridge 26 and a concave ridge 27 between adjacent ridges 26 for forming each spline tooth 13 are provided. The end surfaces 26a, 27a of the convex ridges 26 and the concave ridges 27 on the small diameter portion 24b side are orthogonal to the axis of the punch 24.

The lower mold 22 includes a lower holder 28, a die 29 held by the lower holder 28 and cooperating with the punch 24, and a knockout block slidably fitted to a lower portion of the die hole 30 of the die 29.
31 and a knockout pin 32 penetrating through the center of the bottom of the die 29 and the lower holder 28 so that the distal end faces the lower surface of the knockout block 31. Knockout block 31 has a positioning hole 31a on its upper surface for fitting with the fitting projection 25a.

The die hole 30 has the following regions from the top in order. That is, the blank placement area existing in the opening
m ₁ , rough drawing region m ₂ , drawing region m _3, and ironing region m ₄ . The ironing area m ₄ is the housing 1
An upper zone n corresponding to the large-diameter cylinder 3 _1, the more the lower zone p corresponding to the small diameter cylinder 3 _2.

The blank mounting region m ₁ has a maximum diameter in the die hole 30, also a rough drawing area m ₂ has a diameter that gradually decreases downward. In drawing area m _3, the lower diameter mold
22 are set equally over the entire length in the elevating direction. In the ironing top zone n processing region m _4, the upper half n ₁ is intended to be used for forming the cylindrical surface b, a diameter equal over the lifting direction entire length of the lower mold 22, and drawing smaller than the diameter of the region m _3. On the other hand, the lower half n _2, the recesses
In order to form 20, the ridge 33 corresponding to each ridge 27 of the punch 24
And, in order to form a convex portion 34 between each concave portion 20, a concave line 35 corresponding to each convex line 26 of the punch 24 is provided. The upper end of the Kakutotsujo 33 is continuous to the upper half n ₁ via a gentle slope r.

Hitting the molding of the housing 1 is positioned by fitting the circular blank 37 formed the positioning hole 37a in the center, as shown in FIG. 5 blank placing area m ₁ die 29.

As shown in FIG. 7, the lower mold 22 is raised to allow the fitting projection 25a to penetrate the positioning hole 37a of the blank 37, and
The raises subjected to rough drawing the blank 37 in cooperation with the punch 24 and die 29 in the rough drawing area m _2.

As shown in FIG. 8, subsequently raising the lower mold 22 is subjected to drawing process blank 37 in cooperation with the punch 24 and die 29 in the drawing area m _3. By this drawing, the cylindrical part
An intermediate body having an end wall 38b at one end of the cylindrical portion 38a, and the spline grooves 12 and the spline teeth 13 of the spline Sp roughly formed on the inner peripheral surface of the cylindrical portion 38a.
Get 38.

As shown in FIG. 9, to further raise the lower die 22, in cooperation with the punch 24 and die 29 in the ironing area m _4, the cylindrical portion of the intermediate 38 which was positioned an end wall 38b in the processing direction front side 38a is ironed, and the fitting projection 25a is positioned
Fits 31a. In this ironing process, the cylindrical portion 3 of the intermediate body 38
Since the material flows upward in 8a, the molding of the housing 1 can be performed with the completion accuracy without cutting the fiber flow.

That is, the small diameter cylinder 3 ₂ is molded in the lower area p cooperation with the small-diameter portion 24b and the die hole 30 of the punch 24. The large-diameter 3 in the upper zone n cooperation with the large-diameter portion 24a and the die hole 30 of the punch 24 ₁
Is molded. At this time, each spline groove 12 and each spline tooth 13 are formed by each ridge 26 and each ridge 27 of the punch 24.
But also the cylindrical surface b by halves n ₁ on the upper zone n is each recess 20 is formed in each complete accuracy the ridges 33 of the lower half of n ₂ further.

After the above operation, the lower mold 22 is lowered, and then the knockout block 31 is raised by the knockout pin 32 to release the housing 1.

As described above, when roughing, drawing and ironing are continuously performed by a pair of punches 24 and dies 29,
The molding operation of the housing 1 can be performed efficiently.

A circlip mounting groove 14 is formed by machining in each spline tooth 13 of the housing 1 thus formed.

C. Effects of the Invention According to the invention described in the first aspect, it is possible to provide a durable cylindrical housing for a multi-plate clutch which is lightweight and has improved strength around the mounting groove for the circlip. it can.

According to the invention of the second aspect, by using both drawing and ironing, good dimensional accuracy can be obtained.
In addition, a high-strength cylindrical housing can be efficiently produced.

[Brief description of the drawings]

1 is a longitudinal sectional view of a multi-plate clutch, FIGS. 2 to 4 show a housing, FIG. 2 is a perspective view, FIG. 3 is a plan view of a partly broken main part, and FIG. 4A is a sectional view taken along line IV, FIG. 4A is a sectional view of a main part of a comparative example housing corresponding to FIG. 4, FIGS. 5 and 6 show a housing forming apparatus, FIG.
FIG. 6 is a cross-sectional view showing the relationship between the punch and the die.
7 to 9 are longitudinal sectional views for explaining a housing forming process, FIG. 10 is a perspective view of a conventional housing, and FIG. 11 is FIG. XI-XI. It is a line sectional view. Sp ...... spline, a _1, a ₂ ...... region, b ...... cylindrical surface, c
…… Bottom, m ₃ … Drawing area, m ₄ … Ironing area, 1… Housing, 3… Cylinder, 3a… Opening end face, 5
…… End wall, 11… Drive clutch plate, 12… Spline groove, 13… Spline teeth, 14… Mounting groove, 24… Punch, 29… Dice, 33 …… Protrusion, 37 …… Blank , 38 ...
… Intermediate, 38a …… cylindrical part, 38b …… end wall

Claims (2)

(57) [Claims] A cylinder (3), an end wall (5) connected to one end of the cylinder (3), and an inner peripheral surface of the cylinder (3);
A multi-plate type having a spline (Sp) for slidably fitting a plurality of drive clutch plates (11) and a circlip mounting groove (14) arranged in a ring across the tooth surface of the spline (Sp). In the clutch cylindrical housing, an area (a ₁ ) that is located on the outer peripheral surface of the cylindrical body (3) and includes a portion corresponding to the mounting groove (14) from the opening end surface (3a) of the cylindrical body (3). ) Is formed on a cylindrical surface (b), and each spline tooth () is located on an outer peripheral surface of the cylindrical body (3) and extends from the cylindrical surface (b) to the end wall (5) (a ₂ ). A cylindrical housing for a multi-plate clutch, wherein concave portions (20) corresponding to (13) are provided, and a bottom surface (c) of each concave portion (20) and the cylindrical surface (b) are smoothly continued. A cylindrical portion (38a) and an end wall (38b) connected to one end of the cylindrical portion (38a);
a) A spline groove (12) of a spline (Sp) into which a plurality of drive clutch plates (11) are slidably fitted on an inner peripheral surface;
Mounting grooves for circlip (1
4) The spline teeth (13) to be formed and the roughly formed intermediate (38) are formed by drawing a blank (37), and then the end wall (38b) is moved forward in the processing direction. By ironing the cylindrical portion (38a) while being positioned, the spline groove (1
A cylinder (3) having 2) and spline teeth (13);
Forming an end wall (5) at one end of the cylindrical body (3);
At the same time, on the outer peripheral surface of the cylindrical body (3), the cylindrical body (3)
A region (a ₁ ) including a portion corresponding to the mounting groove (14) from the end surface (3a) of the opening is formed into a cylindrical surface (b) and extends from the cylindrical surface (b) to the end wall (5). For a multi-plate clutch, a recess (20) corresponding to each spline tooth (13) in the area (a ₂ ) and having a bottom surface (c) smoothly connected to the cylindrical surface (b) is formed. A method for forming a cylindrical housing.