JP2008025722A - Belleville spring - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a belleville spring which copes with space reduction in an axial direction in a clutch drum and secures a requested stroke length and a load generated when being flat. <P>SOLUTION: In the belleville spring 1, a plate thickness T<SB>1A</SB>of a thin plate part 10A located to an inner circumference side from a step 10C in a surface is thinner than a plate thickness T<SB>1B</SB>of a thick plate part 10B located to an outer circumference side from the step 10C. An intended stroke length ST<SB>a</SB>and the load P<SB>a</SB>generated when being flat are obtained by appropriately setting the plate thicknesses T<SB>1A</SB>and T<SB>1B</SB>of the thin plate part 10A and the thick plate part 10B. In the case of providing the belleville spring between a piston 3 of a clutch mechanism of a transportation machine and a following plate 4, the belleville spring copes with space reduction in the axial direction in the mechanism in such a way that a surface on which the step 10C is formed, is provided on a piston 3 side so as to contact the thin plate part 10A with the piston 3, and that the thick plate part 10B is provided on the following plate 4 side. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a disc spring used for absorbing shocks generated when a clutch of a multi-plate clutch device of a transport machine is engaged, and more particularly to an improvement technique of a disc spring for coping with downsizing of a multi-plate clutch device. .

  BACKGROUND ART A clutch device for a transport machine such as a CVT (Continuously Variable Transmission) vehicle or an AT (Automatic Transmission) vehicle has a wet multi-plate clutch mechanism. The wet-type multi-plate clutch mechanism includes a clutch drum having a substantially bottomed cylindrical shape, and the clutch drum has a ring-shaped disc spring between a bottom-side driven plate and a piston which are provided so as to be movable in the axial direction. (For example, Patent Document 1). The disc spring is arranged so that its inner peripheral edge is supported by the piston and its outer peripheral edge is supported by the driven plate on the bottom surface side. The disc spring absorbs a shock generated when the clutch of the clutch mechanism is engaged by elastically deforming the disc shape so as to be substantially flat.

  In the load characteristics of the disc spring, the stroke length ST defined by the difference between the height H and the plate thickness T (see FIG. 6) and the load generated when the disc spring is substantially flat during elastic deformation (hereinafter, the load generated when flat) ) Is required as a design value of the clutch mechanism. In addition, when the disc spring is substantially flat, it corresponds when the amount of displacement of the disc spring reaches the stroke length ST.

  The load generated during flatness depends on the inner diameter, outer diameter, plate thickness T, and height H of the disc spring. Among these, the inner diameter and outer diameter of the disc spring are determined in advance by the design value of the internal space of the clutch drum. ing. Thereby, the load generated at the time of flatness is adjusted by the plate thickness T and the height H.

  Recently, in order to reduce the size of the clutch mechanism, the axial space inside the clutch drum has been reduced. However, since the disc spring is required to have a characteristic satisfying the shock reduction function as described above, it is difficult to cope with the reduction in the axial space inside the clutch drum. Therefore, in order to cope with the reduction in the axial space inside the clutch drum, as disclosed in Patent Document 2, the surface of the disc spring pressed by the piston and the surface on the opposite side thereof are formed in a multistage linear shape. It is conceivable to reduce the height H of the disc spring by forming it.

JP-A-9-32918 (Summary) JP-A-9-329155 (FIGS. 7, 8, 11-14)

  However, in the technique of Patent Document 2, since the disc spring is formed in a substantially coin shape in order to reduce the height H of the disc spring, the stroke length ST is very small. For this reason, since the disc spring cannot perform a sufficient stroke, the load characteristic up to the time of substantially flattening shows a sudden change, and the required load generated during flattening cannot be obtained. In particular, in the technique of Patent Document 2, the above-described problem is serious because the contact area of the disc spring with the mating member is set large in order to suppress local high temperature generation of the disc spring in elastic deformation.

  Accordingly, the present invention provides a disc spring that can cope with the reduction in the axial space inside the clutch drum, as well as the required stroke length and flat load. It is an object.

  The disc spring according to the present invention is a ring-shaped disc spring arranged between a second member and a third member provided to be movable in the axial direction inside the cylindrical first member, By forming the step extending in the direction on one surface and forming the other surface in a flat shape, the thickness of one part on the inner peripheral side and the outer peripheral side from the step on the one surface is greater than the thickness of the other part. It is also characterized in that the other member is brought into contact with one part.

Here, the disc spring having a uniform thickness in the radial direction, as shown in FIG. 4, the inner diameter, while the outer diameter, and the stroke length ST _a constant, the thickness T from T ₂ of the point X when the thickness to _{T 1A} of the point Y, if flat when generated load is reduced from _{P a} to _{P 1A,} was increased to a plate thickness T from _{T 2} of the point X to the _{T 1B} of the point Z, the _{P a} The relationship of increasing to P _1B is shown.

In the disc spring of the present invention, by utilizing the above relationship, the plate thicknesses of one portion (hereinafter referred to as a thin plate portion) and the other portion (hereinafter referred to as a thick plate portion) on the inner peripheral side and outer peripheral side of the step on one surface are reduced. By appropriately setting, a desired stroke length and flat load can be obtained. This will be described with reference to FIG. As shown in FIGS. 2A to 2C, it is possible to reduce the space in which the axial space length between the piston 3 and the driven plate 4 of the clutch mechanism is changed from H ₂ to H ₁ (<H ₂ ). Consider the case of obtaining the disc spring 1 of the present invention having the same stroke length and flat load generated as the conventional disc spring 2. Incidentally, the conventional disk spring 2 is radially uniform thickness _{T 2,} has a height _{H 2,} the stroke length ST _a, and flat upon the generated load _{P a.}

In disc spring 1 of the present invention, in order to cope with reduction of the space, while securing the stroke length ST _a thin plate portion 10A in contact with the piston 3, a conventional disc spring plate thickness T _1A of the thin plate portion 10A 2 is set to be smaller than the thickness _{T 2.} Then, since the flat upon the occurrence load per unit area of the thin plate portion 10A is reduced compared with the conventional disc spring 2, to offset the decrease, the thickness T _1B plank portion 10B of the conventional disc springs By setting it larger than the plate thickness T _{2 of} 2, the flat load generated per unit area of the thick plate portion 10B is set larger than that of the conventional disc spring 2. Thus, flat upon the generated load of the whole of the disc spring 1 of the present invention is set to a conventional time same flat disc spring 2 generated load P _a. In the above embodiment, a step is formed on one surface and the thin plate portion is formed on the inner peripheral side of the one surface so as to contact the piston. Instead, a step is formed on the other surface and the thin plate portion is used as a driven plate. Needless to say, it may be formed on the outer peripheral side of the other surface so as to come into contact.

In disc spring 1 of the present invention, as shown in FIG. 2 (B), one surface of a step 10C formed piston having a conventional dish stroke length ST _a and flat during load characteristic P _a of the spring 2 as described above The axial space length between the piston 3 and the driven plate 4 of the clutch mechanism 1 by arranging the thin plate portion 10A in contact with the piston 3 and arranging the other surface of the thick plate portion 10B on the driven plate 4 side. Can be reduced.

  Various configurations can be used in the disc spring of the present invention. For example, two steps can be formed, and the thin plate portion can be a recess formed by two steps. In this case, by providing the mating member in contact with the inside of the groove, it is possible to suppress the radial movement of the mating member relative to the disc spring, so that the mating member is prevented from being detached from the disc spring. Can do.

  In the disc spring of the present invention, the plate thickness of one part (hereinafter referred to as a thin plate part) on the inner peripheral side and the outer peripheral side of the step on one surface is made thinner than the plate thickness of the other part (hereinafter referred to as a thick plate part). Therefore, the desired stroke length and flat load can be obtained by appropriately setting the plate thickness of the thin plate portion and the thick plate portion. In addition, when it is provided between the piston and the driven plate of the clutch mechanism of the transport machine, one surface on which a step is formed is arranged on one member side so that the thin plate portion is brought into contact with one member, and the other surface of the thick plate portion is provided. By disposing on the other member side, it is possible to cope with a reduction in axial space in the mechanism.

(1) Configuration of disc spring Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram illustrating a configuration of a disc spring 1 according to an embodiment of the present invention. 1A is a plan view, and FIG. 1B is a side sectional view taken along line 1B-1B in FIG. In addition, the partial enlarged view of the disc spring 1 is FIG. 2 (B).

As shown in FIGS. 1A, 1B, and 2B, the disc spring 1 includes a main body 10 having a ring-shaped disc shape, and a circular hole 11 is formed at the center of the main body 10. Has been. A step 10C extending in the circumferential direction is formed on one surface of the main body 10, and the other surface of the main body 10 is formed in a flat shape. Thus, the thin plate portion 10A is formed on the inner peripheral side than the step 10A of the body 10, thick plate portion 1B is formed on the outer peripheral side than the step 10C, the thickness _{T 1A} of the thin plate portion 10A is the thickness of the thick portion 10B _Thinner than T1B. In the present embodiment, the stroke length ST _a and flat when the generated load _{P a} of the disc spring 1 has a height _H 2 and having a radially uniform thickness _{T 2 (T 1A <T 2} <T 1B) (> Equivalent to a conventional disc spring 2 having H ₁ ).

In addition, the disc spring to which this invention is applied is not limited to the disc spring 1 shown by FIG. 1 (A), (B), FIG. 2 (B), A various structure can be used. For example, the shape of the thin plate portion of the present invention can be arbitrarily set so as to correspond to the shape of the piston. For example, like the disc spring 200 shown in FIG. 3, the thin plate portion 210 </ b> A can be a groove 210 </ b> D formed by two steps 210 </ b> C <b> 1 and 210 </ b> C <b> 2 extending in the circumferential direction. The thick plate portions 210B1 and 210B2 are formed on both sides of the recess 210D. The thin plate portion 210A has the same thickness T _1A as the thin plate portion 10B, and the thick plate portion 210B has the same thickness T _1B as the thin plate portion 10B. In the disc spring 200, by providing the piston 3 in contact with the inside of the recess 210D, it is possible to suppress the radial movement of the piston 3 with respect to the disc spring 200. Separation can be prevented.

Further, instead of forming the step 10C on one surface and forming the thin plate portion 10A on the inner peripheral side of the one surface so that the inner peripheral edge of the thin plate portion 10A contacts the piston 3, the step 10C is formed on the other surface. The thin plate portion can be formed on the outer peripheral side of the other surface so that the outer peripheral edge portion of the portion 10A is in contact with the driven plate. As described above in the modified example, the height H ₁ by appropriately designing the thickness of the thin portion and thick _portion, stroke length ST _a, it is needless to say it is possible to obtain a flat at the generated load P _a is there.

(2) Method for Manufacturing Disc Spring Next, a method for manufacturing the disc spring 1 will be described. First, by press working, punching the blank ring-shaped plate material having a thickness T _1B. Subsequently, while quenching the blank ring-shaped, performs a form of bending and the step 10C to dish-shaped, thin plate portion 10A having a thickness T _1A on the inner peripheral side of the one surface, the plate thickness on the outer peripheral side of the one surface forming a thick portion 10B having a T _1B. Next, by performing tempering, the disc spring 1 having the above-described configuration is obtained.

In addition, the manufacturing method of the disc spring to which this invention is applied is not limited to the said manufacturing method, A various method can be used. For example, first, using a plurality of steps single die capable of performing the (mold of the so-called progressive die), by press working, with punching a ring-shaped blanks from sheet material having a thickness T _1B, the ring By forming the step 10C on the sheet-like blank, the thin plate portion 10A having the plate thickness T _1A on the inner peripheral side of one surface and the thick plate portion 10B having the plate thickness T _1B on the outer peripheral side of the one surface are formed. Next, the blank is bent into a dish shape at room temperature, and the dish spring 1 is obtained by quenching and tempering the dish-shaped blank.

(3) Configuration of Clutch Mechanism The disc spring 1 described above can be applied to a clutch mechanism 100 as shown in FIG. FIG. 2 is an enlarged side sectional view showing the configuration of the clutch mechanism 100. The following piston 105 and driven plate 103 correspond to the piston 3 and driven plate 4 in FIGS.

  The clutch mechanism 100 includes a clutch drum 101 having a substantially bottomed cylindrical shape. On the inner peripheral surface of the clutch drum 101, a plurality of spline grooves 101A extending in the axial direction are formed at equal intervals in the circumferential direction. A cylindrical clutch hub 102 whose rotational axis line coincides with the clutch drum 101 is provided inside the clutch drum 101, and a plurality of spline grooves 102 </ b> A extending in the axial direction are arranged at equal intervals in the circumferential direction on the outer peripheral surface thereof. Is formed.

  Between the clutch drum 101 and the clutch hub 102, a driven plate 103 fitted in the spline groove 101A of the clutch drum 101 and a drive plate 104 fitted in the spline groove 102A of the clutch hub 102 move in the axial direction. They are arranged alternately at a predetermined interval. A piston 105 is disposed on the bottom surface side of the clutch drum 101 so as to be movable in the axial direction. A hydraulic chamber 106 to which hydraulic oil is supplied is formed between the clutch drum 101 and the piston 105. One end of a return spring 107 that is expanded and contracted by pressure applied thereto is fixed to the opening side surface of the piston 105. The other end of the return spring 107 is fixed to a spring retainer 108 provided on the clutch drum 101. The return spring 107 biases the piston 105 toward the bottom surface side of the clutch drum 101.

  The disc spring 1 is disposed between the driven plate 103 on the bottom side of the clutch drum 101 and the piston 105. In the disc spring 1, one surface on which the step 10C is formed is disposed on the piston 105 side, the inner peripheral edge of the thin plate portion 10A is supported by the piston 105, and the other surface is disposed on the driven plate 103 side. The outer peripheral edge is supported by the driven plate 103. Thereby, the disc spring 1 can be moved in the axial direction. A retaining plate 109 for supporting the driven plate 103 and the drive plate 104 is disposed on the opening side of the clutch drum 101. On the opening side surface of the retaining plate 109, a snap ring 110 is disposed to prevent the retaining plate 109 from being detached to the outside.

(4) Operation of clutch mechanism
Next, the operation of the clutch mechanism 100 to which the disc spring 1 is applied will be described mainly with reference to FIG.

When hydraulic oil is supplied to the hydraulic chamber 106, the piston 105 driven by the hydraulic pressure moves to the opening side in the axial direction against the urging force of the return spring 107, and the bottom side of the clutch drum 101 via the disc spring 1. The driven plate 103 is pressed. Then, the driven plate 103, the drive plate 104, and the retaining plate 109 that are alternately arranged move to the opening side in the axial direction. When the retaining plate 109 is pressed against the snap ring 110 by such movement, the friction surfaces of the driven plate 103 and the drive plate 104 facing each other are engaged and the clutch is engaged. Thereby, torque transmission between the clutch drum 101 and the clutch hub 102 becomes possible. At this time, the disc spring 1 absorbs a shock generated at the time of clutch engagement by elastically deforming the disc shape so as to become substantially flat. Flat upon the generated load of the disc spring 1 at this time is P _a.

  Next, when the hydraulic oil in the hydraulic chamber 106 is discharged, the piston 105 is pushed back to the bottom surface side of the clutch drum 101 by the urging force of the return spring 107. Then, the engagement of the friction surfaces of the driven plate 103 and the drive plate 104 is released, the clutch engagement is released, and the shape of the disc spring 1 returns to the original state.

In disc spring 1 of the present embodiment, the thickness T _1A of the inner circumferential side of the thin plate portion 10A from the step 10C in one aspect, since the thinner than the plate thickness T _1B of the outer peripheral side of the thick plate portions 10B than the step 10C by setting the thickness _T 1A of the thin plate portion 10A and the thick part _10B, the _{T 1B} appropriately, it is possible to obtain a desired stroke length ST _a and flat when the generated load _{P a.} Further, in the case of providing between the piston 105 and the driven plate 103 of the clutch mechanism 100 of the transport machine, one surface on which a step is formed is disposed on the piston 105 side, the thin plate portion 10A is brought into contact with the piston 103, and the thick plate portion 10B is provided. By disposing on the driven plate 103 side, it is possible to cope with a reduction in axial space in the mechanism.

(5) Modifications As described above, the present invention has been described with reference to the above embodiment. However, the present invention is not limited to the above embodiment, and various modifications can be made. For example, a plurality of teeth protruding outward in the radial direction may be formed on the outer peripheral portion of the disc spring 1. The teeth of the disc spring 1 are fitted into the spline grooves 101A of the clutch drum 101 in the clutch mechanism 100, and have a function of preventing the disc spring 1 from rotating relative to the clutch drum 101.

  Furthermore, in the said embodiment, although this invention was applied to the multi-plate clutch apparatus of the CVT vehicle of a motor vehicle, it is not limited to this. For example, the present invention can be applied to a multi-plate clutch device of a transport machine such as an AT car of a car, a construction machine, or a motorcycle. Moreover, in the said embodiment, although the generation load at the time of when they become substantially flat was used as generation load of the disc spring 1 in the clutch mechanism 100, it is not limited to this, They are substantially It goes without saying that the generated load at the desired stroke length ST before flattening can be used.

The structure of the disc spring which concerns on one Embodiment of this invention is represented, (A) is a top view, (B) is a sectional side view of the 1B-1B line | wire of (A). The clutch mechanism provided with various disc springs is represented, (A) is a partial sectional view showing a clutch mechanism provided with a conventional disc spring, and (B) is a portion showing the clutch mechanism provided with the disc spring of the present invention. Sectional drawing (C) is a partial sectional view for comparing the disc spring of the present invention with a conventional disc spring. It is a fragmentary sectional view of the clutch mechanism provided with the modification of the disc spring concerning one embodiment of the present invention. It is a related figure of stroke length ST of various disc springs which have a uniform plate thickness in the radial direction, and load P generated when flat. It is a sectional side view showing the structure of the multi-plate clutch mechanism to which the disc spring of FIG. 1 is applied. It is a sectional side view showing the configuration of a disc spring and showing the relationship between the stroke length ST, the plate thickness T, and the height H.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Belleville spring, 10A, 210A ... Thin plate part, 10B, 210B1, 210B2 ... Thick plate part, 10C, 210C1, 210C2 ... Step, 100 ... Clutch mechanism, 101 ... Clutch drum (first member), 4,103 ... Follower Plate (second member), 3,105 ... piston (third member)

Claims (2)

In the ring-shaped disc spring disposed between the second member and the third member provided to be movable in the axial direction inside the cylindrical first member,
By forming a step extending in the circumferential direction on one surface and forming the other surface in a flat shape, the thickness of one portion on the inner and outer sides of the step on the one surface is set to the thickness of the other portion. A disc spring characterized in that it is thinner than the plate thickness and the mating member is brought into contact with the one portion.   2. The disc spring according to claim 1, wherein there are two steps, and the one portion is a concave line formed by the two steps.

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