JP2000179626A - V-belt for continuously variable transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress generation of the wear of an element and a side wall of a pulley V-shaped groove by setting the clearance at a lower end part of a fitting part to be formed by a fitting projection of the element and a fitting hole to be smaller than the clearance at an upper end part to suppress the floating of the element. SOLUTION: Elements 20, 20 adjacent to each other are mutually bent to transmit the pressing force. The preceding element 20 can be floated by the clearance r20 present at a lower end part of a fitting part which is formed by a fitting projection 20p and a fitting hole 20h. Since r20 is set to be smaller than the clearance r1 (r20<r1), the maximum floating at an outlet part of an input pulley can be reduced even when every element to which the pressing force is applied is continuously floated. Generation of the wear of the element 20 and a side wall of a V-shaped groove of the pulley can be suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a V-belt which transmits power by being wound around a conical pulley of a continuously variable transmission.

[0002]

2. Description of the Related Art Conventionally proposed general V-belt type continuously variable transmissions include, for example, Japanese Utility Model Laid-Open No. 63-72347.
As described in Japanese Patent Application Laid-Open Publication No. H10-209, there has been widely known an apparatus including main parts schematically shown in FIGS. 8 and 9. In addition, FIG.
It is the conceptual diagram which showed FIG. 8 from the side. The continuously variable transmission includes a pulley V of the input pulley 21 that is driven to rotate about the axis Oi.
The V belt 1 is wound around the groove side wall 21a and the pulley V groove side wall 22a of the output pulley 22 rotated around an axis Oo parallel to the axis Oi. From the above configuration, the power of the input pulley 21 is transmitted to the output pulley 22 via the V-belt 1, and during the transmission of this power, the movable flanges 21b of the input / output pulleys 21 and 22, as shown in FIG.
22b is displaced in the axial direction as shown by arrows A and B,
By moving the movable flange 21b closer to the fixed flange 21c and moving the movable flange 22b away from the fixed flange 22c, the effective radius of the V belt 1 around the input / output pulleys 21 and 22 is continuously changed.
It functions as a continuously variable transmission. Such a V
As one of the V-belts used in the belt-type continuously variable transmission, a laminated ring configured by laminating a plurality of endless rings, and a connecting ring are arranged so as to be able to abut each other in the circumferential direction of the laminated ring. V-belts composed of a number of V-type elements are widely known (for example, Japanese Patent Publication No. 55-55).
No. 6783).

FIGS. 10 and 11 show a front view and a side view of a general element 2 used for such a V-belt, respectively. To explain this, the element 2 has inclined side surfaces 2d, 2d that come into frictional contact with the V groove side wall of the input / output pulley.
And concave slits 2s, 2s are formed,
The V-belt 1 is configured as shown in FIGS. 8 and 9 by fitting the lamination ring 3 from left and right into a slit of an annular assembly formed by arranging and connecting the elements 2 in an annular manner. Reference numerals 2a and 2a denote sliding surfaces with the laminated ring 3. The front end face 2f of the element 2 is formed with a slope 2m whose wall thickness decreases toward the lower side.
m, the adjacent elements 2 and 2 are relatively bent about the rocking edge 2e, which is the starting position of the m.
Around the pulley V-groove side walls 21a, 22a. A cylindrical (or conical) fitting projection 2p is provided above the front end face 2f of the element 2.
In addition, a fitting hole 2h is formed concentrically above the rear end face 2b, and as shown in FIG.
(the direction in which p faces is the traveling direction) The fitting projection 2p of the subsequent element 2 is fitted to the fitting hole 2h of the element 2 that is adjacent thereto, so that the adjacent element 2,
The positions of the elements 2 are regulated with each other, and the elements 2 arranged in a ring are continuously positioned. Therefore, in the linear portion of the V-belt 1 wound between the input and output pulleys, the displacement between the adjacent elements 2 and 2 is suppressed, so that the element 2 is smoothly engaged with the input and output pulleys, Vibration and noise of the V-belt are reduced. The method of continuously positioning and arranging the elements by fitting the fitting projection and the fitting hole in this manner is as follows.
JP-A-55-100443 and JP-A-55-10
It is widely known, for example, from US Pat.

[0004]

However, in the above-structured V-belt for a continuously variable transmission, the element 2
A clearance is required between the fitting projection 2p and the fitting hole 2h to allow the element 2 to bend at the pulley winding portion. FIG. 13 is an enlarged view showing a state in which the fitting projection 2p of the element 2 and the fitting hole 2h are fitted in the linear portion of the V-belt 1, and the X axis and the Y axis are respectively shown. Element 2 width (left and right) direction and height (up and down)
Indicates the direction. Here, the fitting projection 2p and the fitting hole 2h
Since both have a perfect circular cross section, a certain clearance exists in the entire circumferential direction between the fitting projection 2p and the fitting hole 2h. Note that in FIG.
1 and r2 respectively indicate the clearance between the upper end and the lower end of the fitting portion formed by the fitting projection and the fitting hole,
The relationship is r1 = r2. Next, FIG. 12 is a view showing a cross section of two adjacent elements in a bent state viewed from the side. In this figure, the angle θ is the radius at which the V belt 1 has the smallest radius. It shows the relative bending angle between adjacent elements 2, 2 when wound between input and output pulleys. By setting the clearance of the fitting portion to a minimum dimension where the fitting projection 2p and the fitting hole 2h do not interfere (bend is allowed) in such a maximum bending state, the fitting projection 2p and the fitting hole 2h are adjacent to each other. The positioning of the elements 2 and 2 is most reliably performed. However, because of the clearance provided to allow the bending of the element 2, the positional deviation between the adjacent elements 2, 2 is allowed.
When a pushing force acts on the element 2 on the input pulley 21, a floating phenomenon occurs in which the winding radius of the element 2 becomes larger than an ideal radius locus (constant radius), as shown in FIG. In FIG. 14, an element in which the colored element 2 transmits the pressing force is shown, and this lifting is caused by the radial component of the pressing force acting on the element 2 from the front and rear elements. It is generated by being pushed outward in the radial direction, and the relative lifting amount of the adjacent elements 2, 2 is:
In the bent state, it is equal to the sum of the vertical clearance of the fitting portion formed by the fitting projection 2p and the fitting hole 2h. To explain this, for example, as shown in FIG.
In a state in which the adjacent elements 2 and 2 are relatively bent by the angle θ, the preceding element 2 is separated from the adjacent subsequent element 2 by the fitting projection 2p and the fitting hole 2h. Since the clearance r2 (= r1) existing at the lower end of the formed fitting portion can be lifted (the clearance r1 at the upper end existing in a linear state has disappeared), as shown in FIG. All the elements 2 on which the force acts are continuously raised (in a stepwise manner), and the maximum lifting (hereinafter referred to as dR1) occurs at the V-belt engaging portion of the input pulley 21. When the element 2 floats on the input pulley in this way, the contact surface pressure between the raised element 2 and the V groove side wall 21a of the input pulley 21 decreases. 21
The contact surface pressure with the V-groove side wall 21a increases, and the inclined end surface 2d of the element 2 and the input pulley 2
There was a problem that the V groove side wall 21a was liable to be worn.

The present invention has been made in view of the above problems, and suppresses the lifting of an element which occurs when a V-belt transmits a pressing force at a pulley-wound portion, thereby causing abrasion of the element and the side wall of the pulley V-groove. It is an object of the present invention to provide a V-belt for a continuously variable transmission that can suppress the occurrence of a vehicular belt.

[0006]

To achieve the above object, a V-belt for a continuously variable transmission according to the first aspect of the present invention comprises a laminated ring formed by laminating a plurality of endless rings, It is composed of a large number of V-shaped elements which are arranged so as to be able to contact each other in the circumferential direction of the laminated ring, and an inclined surface with a reduced thickness is formed below each of these elements.
A V-belt for a continuously variable transmission that transmits power by being wound between input / output pulleys by adjacent elements being relatively bent, wherein the V-belt is one of a front surface and a rear surface in the traveling direction of each element. At least one or more fitting protrusions on one surface and a fitting hole on the other surface are formed,
In a continuously variable transmission V-belt in which adjacent elements are positioned relative to each other, a clearance at a lower end of a fitting portion formed by a fitting projection and a fitting hole of the element is set to be smaller than a clearance at an upper end. It is characterized by doing. A V-belt for a continuously variable transmission according to a second aspect of the present invention is the V-belt for a continuously variable transmission according to the first aspect, wherein the fitting projection and the fitting hole of the element are formed in a cylindrical shape or a conical shape, respectively. The vertical center of the joint projection is set to be offset below the vertical center of the fitting hole. A V-belt for a continuously variable transmission according to a third aspect of the present invention is the V-belt for a continuously variable transmission according to the first or second aspect, wherein a lower end portion of a fitting portion formed by a fitting projection and a fitting hole of the element. Is set to zero.

[0007]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. 1 and 2 show a front view and a side view, respectively, of an element 20 according to the first embodiment of the present invention. This element 20 is provided in place of the element 2 of the conventional example.
The same components as those in the conventional example are denoted by the same reference numerals, and redundant description will be omitted.

The fitting projection 20p and the fitting hole 20h of the element 20 are both formed in a cylindrical shape whose cross section is a perfect circle, and the center of the fitting projection 20p in the vertical direction is the top and bottom of the fitting hole 20h. It is offset by δ below the center of the direction.

FIG. 3 shows a V composed of elements 20.
FIG. 4 is an enlarged view showing a state in which a fitting projection 20p of the element 20 and a fitting hole 20h are fitted in a straight portion of the belt 10. Here, r1 and r20 are the fitting protrusions 2
0p and the clearance at the upper end and the lower end of the fitting portion formed by the fitting hole 20h, respectively.
In the present embodiment, r20 <r1 because the vertical center of the fitting hole 20h and the fitting hole 20h are offset.
Note that the clearance r1 at the upper end of the present embodiment is set equal to the clearance r1 at the upper end of the conventional example.

FIG. 4 is a side view of a cross section of two adjacent elements in a bent state. In this figure, the angle .theta.
Indicates the relative bending angle between the adjacent elements 20, 20 when wound between the input / output pulleys 21, 22 with the smallest radius.

Hereinafter, the operation of the element 20 configured as described above will be described. In FIG. 4, considering the state in which the adjacent elements 20, 20 are bent and transmit the pressing force to each other, the preceding element 20 is adjacent and follows as in the above-described conventional example. The element 20 can be lifted up by the clearance r20 existing at the lower end of the fitting portion formed by the fitting projection 20p and the fitting hole 20h (the clearance r1 at the upper end existing in a linear state disappears. However, since r20 in the present embodiment is set to be smaller than the clearance r2 in the above-described conventional example (r20 <r2 = r1), as in the above-described conventional example, all of the portions to which the pressing force acts are used. Of the element 2 of the input pulley 21, even if the element 2 of the input pulley 21 is continuously raised (in a stepwise manner).
Is the lifting amount dR in the conventional example shown in FIG.
It can be smaller than one (see FIG. 5).

As described above, the element 2 of the present embodiment
0, the bending of the V-belt 10 at the pulley wrapping portion is allowed in the same manner as the conventional V-belt, while the element 20 generated when the V-belt 10 transmits the pressing force at the pulley wrapping portion. Of the element 20 and the side walls 21a, 22 of the pulley V-groove can be reduced.
a can be suppressed from occurring.

FIG. 6 is a front view of an element 20 'according to a second embodiment of the present invention. The element 20 'is provided in place of the element 2 of the conventional example, and the same elements as those of the conventional example are denoted by the same reference numerals, and redundant description is omitted.

The fitting hole 20h 'of the element 20' is
Although the cross-sectional shape is formed in a perfect circular cylindrical shape, the fitting projection 20p 'formed concentrically with the fitting hole 20h' is formed in a shape combining semi-cylindrical shapes having different radii in the upper and lower directions. Have been.

FIG. 7 is an enlarged view showing a state in which a fitting projection 20p 'and a fitting hole 20h' of the element 20 'are fitted in a straight portion of a V-belt 10' (not shown) composed of the element 20 '. FIG. Here, r1 and r20 ′ denote the clearance between the upper end and the lower end of the fitting portion formed by the fitting projection and the fitting hole, respectively, and have a radius of the semi-cylindrical shape of the upper half of the fitting projection 20p ′. Is set to be smaller than the radius of the lower half-cylindrical shape, so that r20 ′ <r1 in the present embodiment.

Therefore, the V-belt 10 ′ is also provided in the element 20 ′ of the present embodiment, just like the first embodiment.
In the same manner as the conventional V-belt, it is possible to reduce the lifting of the element 20 'which occurs when the V-belt 10' transmits the pushing force at the pulley-wrapping portion, while allowing the bending at the pulley-wrapping portion as in the conventional V-belt. Possible, element 2
It is possible to suppress the occurrence of wear on the 0 ′ and the pulley V-groove side walls 21a, 22a.

In the first and second embodiments,
In this case, if the clearance at the lower end of the fitting portion formed by the fitting projection and the fitting hole of the element is set to zero, the vertical positional deviation of the adjacent element is reduced by about Since it can be reduced by half, the effect and effect of suppressing the generation of wear on the side wall of the element and the pulley V-groove can be obtained most remarkably.

[0018]

As described above, in the V-belt for a continuously variable transmission according to the first aspect of the present invention, the clearance at the lower end of the fitting portion formed by the fitting projection and the fitting hole of the element is reduced. Since it was set smaller than the clearance at the upper end,
The lifting of the element, which occurs when the V belt transmits the pressing force at the pulley winding portion, is reduced, and the occurrence of wear on the element and the side wall of the pulley V-groove can be suppressed. In the V-belt for a continuously variable transmission according to the second aspect of the present invention, the fitting projection and the fitting hole of the element are each formed in a cylindrical shape or a conical shape, and the center of the fitting projection in the vertical direction is fitted. Since the hole is set to be offset below the center in the vertical direction, the operation and effect of the invention described in claim 1 can be reliably obtained. In the V-belt for a continuously variable transmission according to the third aspect of the present invention, the clearance at the lower end of the fitting portion formed by the fitting projection and the fitting hole of the element is set to zero. The operation and effect of the invention described in claim 2 are most remarkable.

[Brief description of the drawings]

FIG. 1 is a front view showing a first embodiment according to the present invention.

FIG. 2 is a side view of FIG.

FIG. 3 is an enlarged view of a main part showing a fitting state of a fitting projection and a fitting hole of the element according to the first embodiment.

FIG. 4 is a side view showing a fitting state of a fitting projection and a fitting hole of the element according to the first embodiment.

FIG. 5 is a conceptual diagram showing lifting of an element on a pulley according to the first embodiment.

FIG. 6 is a front view showing a second embodiment according to the present invention.

FIG. 7 is an enlarged view of a main part showing a fitting state of a fitting projection and a fitting hole of an element according to the second embodiment.

FIG. 8 is an explanatory diagram showing a main part of a V-belt type continuously variable transmission.

FIG. 9 is a conceptual diagram showing FIG. 8 from the side.

FIG. 10 is a front view showing a conventional element.

FIG. 11 is a side view of FIG. 10;

FIG. 12 is a side view showing a fitting state of a fitting projection and a fitting hole of a conventional element.

FIG. 13 is an enlarged view of a main part showing a fitting state of a fitting projection and a fitting hole of a conventional element.

FIG. 14 is a conceptual diagram showing the lifting of a conventional element on a pulley.

[Explanation of symbols]

 2a Sliding surface 2b Back end surface 2d Inclined side surface 2e Locking edge 2f Front end surface 2h Fitting hole 2m Inclined surface 2p Fitting protrusion 2s Slit 3 Lamination ring 10 V belt 10 'V belt 20 Element 20' Element 20h Fitting hole 20h ' Fitting hole 20p Fitting projection 20p 'Fitting projection 21 Input pulley 21a Pulley V groove side wall 21b Movable flange 21c Fixed flange 22 Output pulley 22a Pulley V groove side wall 22b Movable flange 22c Fixed flange

Claims (3)

[Claims] 1. A laminated ring constituted by laminating a plurality of endless rings, and a large number of V-shaped elements which are arranged so as to be able to contact each other in the circumferential direction of the laminated ring. A continuously variable transmission that transmits power by being wound between input and output pulleys by forming an inclined surface with a reduced plate thickness below each element so that adjacent elements bend relatively to each other. V-belt for
A continuously variable transmission in which at least one or more fitting protrusions and a fitting hole are formed on one of one of a front surface and a rear surface in the traveling direction of each of the elements so that adjacent elements are positioned relative to each other. In the V-belt for a continuously variable transmission, the clearance at the lower end of the fitting portion formed by the fitting projection and the fitting hole of the element is set smaller than the clearance at the upper end. V belt. 2. The fitting projection and the fitting hole of the element are each formed in a cylindrical shape or a conical shape, and the vertical center of the fitting projection is lower than the vertical center of the fitting hole. 2. The V-belt for a continuously variable transmission according to claim 1, wherein the V-belt is set so as to be offset. 3. A clearance set at a lower end portion of a fitting portion formed by a fitting projection and a fitting hole of the element is set to be zero. The V-belt for a continuously variable transmission according to the above.