JPH10169719A - V-belt for continuously variable transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the durability of rings on the inner peripheral side and the whole of a laminated ring. SOLUTION: In a V-belt for continuously variable transmissions, which is made up of a laminated ring 11 formed in a laminar manner by fitting plural endless-like rings on each other, and a number of V-type elements mutually connected and arranged in the circumferential direction of the laminated ring so that they can abut on each other, a fitting clearance between adjacent rings is set to a minus clearance. Thus, the peripheral length of the rings on the outer peripheral side becomes shorter, tensile stress acting on the endless-like rings becomes larger on the outer peripheral side where bending stress is small, and tensile stress of the endless-like rings is reduced on the inner peripheral side where bending stress is large.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an improvement in a V-belt for a continuously variable transmission.

[0002]

2. Description of the Related Art A conventional V-belt for a continuously variable transmission is shown in FIGS.
As shown in FIG. 9, a plurality of endless rings 1 a to 1 n are fitted to each other and stacked in a layered manner, and connected to each other in the circumferential direction of the stacked ring 1 so as to be able to contact each other. And a number of V-shaped elements 2 arranged in a row.

As shown in FIGS. 10 and 11, this type of V-belt for a continuously variable transmission has an input pulley 3 connected to an engine or the like and an output pulley 4 connected to an output shaft.
Around the V-shaped side 2 of the element 2
a and the conical surfaces 3a, 4a of the input / output pulleys 3, 4 transmit the rotational force by the contact frictional force. The input and output pulleys 3 and 4 are configured so that the width of the V-shaped groove can be changed.
By changing the friction contact position of the V-belt to the input / output pulleys 3 and 4 inward and outward in the radial direction, the running radius of the V-belt, that is, the speed ratio is continuously changed to function as a continuously variable transmission (actually opened (See, for example, JP-A-63-72347).

[0004]

In such a conventional laminated ring 1 for a V-belt for a continuously variable transmission, the peripheral lengths of the endless rings 1a, 1b, 1c,. And fitting them together.

That is, the inner diameter d1 of the non-terminal ring 1a, which is the innermost circumference, is determined so as to have a predetermined peripheral length, and the non-terminal ring 1b is closely fitted to the outer circumference of the non-terminal ring 1a. The inner diameter d2 of the endless ring 1a
In anticipation of 1, it is determined that d2 = d1 + 2 × t1. Next, the inner diameter d3 of the endless ring 1c is adjusted so that the endless ring 1c is closely fitted to the outer periphery of the endless ring 1b.
In consideration of the plate thickness t2 of b, d3 = d2 + 2 × t2 is determined. Hereinafter, the above contents are sequentially repeated to determine the circumferential length of the outermost endless ring 1n. As shown in FIG. 9, the endless rings 1a, 1b, 1c,. Thus, the laminated ring 1 is manufactured.

However, in such a laminated ring 1, when the V-belt is formed and wound around the pulleys 3 and 4, each of the endless rings 1 a, 1 b, 1 c, and ... Because the winding radius of 1n increases toward the outer circumference by the thickness of the ring, the bending stress acting on the inner circumference ring becomes larger than the bending stress acting on the outer circumference ring due to the difference in the winding radius. The durability of the inner peripheral ring, especially the innermost peripheral ring 1a, is relatively reduced.

While the endless rings 1a, 1b, 1c,... 1n are subjected to tensile stress when power is transmitted by the V-belt, when the durability of the inner peripheral ring is reduced,
This may affect the entire laminated ring 1.

[0008] The present invention is to equalize the stress generated in each endless ring constituting the laminated ring,
The purpose is to solve such problems.

[0009]

According to a first aspect of the present invention, there is provided a laminated ring in which a plurality of endless rings are fitted and formed in a layered form, and the laminated ring is connected to each other in a circumferential direction so as to be able to contact each other. In a V-belt for a continuously variable transmission composed of a number of V-shaped elements arranged, the clearance between adjacent rings of the laminated ring is set to a minus clearance.

According to a second aspect of the present invention, there is provided a laminated ring in which a plurality of endless rings are fitted and formed in a layer shape, and a large number of V arranged so as to be in contact with each other in the circumferential direction of the laminated ring. In a V-belt for a continuously variable transmission including a mold element, a fitting clearance between adjacent rings of the laminated ring is set in a range of 0 to −5 μm.

According to a third aspect of the present invention, in the first or second aspect, a clearance between adjacent rings of the laminated ring is a sectional shape of the endless ring, a circumferential length of the laminated ring, a laminated ring when a belt is used. Is set based on the minimum radius of curvature of.

According to a fourth aspect of the present invention, in the first or second aspect, the fitting clearance between adjacent rings of the laminated ring is such that stress generated from the innermost peripheral ring to the outermost peripheral ring of the laminated ring when the belt is used. Set to be almost equal.

According to a fifth aspect of the present invention, there is provided a laminated ring in which a plurality of endless rings are fitted and formed in a layered form, and a plurality of Vs arranged so as to be able to contact each other in the circumferential direction of the laminated ring. In a V-belt for a continuously variable transmission including a mold element, an outer peripheral length of an inner ring before fitting between adjacent rings of the laminated ring is equal to or longer than an inner peripheral length of the outer ring.

[0014]

According to the first aspect of the invention, when the belt is set between the pulleys, the bending stress acting on each endless ring of the laminated ring becomes larger toward the inner peripheral side, but the bending stress acting on the adjacent ring of the laminated ring increases. In order to set the mating clearance to a negative clearance, the ring circumference on the outer peripheral side is shortened, and the tensile stress acting on the non-terminal ring increases on the outer peripheral side where the bending stress is smaller, and the bending stress is larger. On the peripheral side, the tensile stress of the endless ring is reduced.

Therefore, the total stress generated in each endless ring can be equalized, and the durability of the inner peripheral ring and the entire laminated ring can be greatly improved.

According to the second aspect, by setting the fitting clearance between the adjacent rings of the laminated ring in the range of 0 to -5 μm, the durability of the inner peripheral ring and the entire laminated ring can be easily achieved. Can be improved.

According to the third aspect, the fitting clearance between the adjacent rings of the laminated ring can be properly set.

According to the fourth aspect, the durability of the inner peripheral ring and the entire laminated ring can be improved by setting the fitting clearance.

According to the fifth aspect, the durability of the inner peripheral ring and the entire laminated ring can be improved by setting the respective ring lengths.

[0020]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a laminated ring 11 according to the first embodiment.
Is shown.

The laminated ring 11 is assembled by fitting a total of ten endless rings 11a to 11n with each other.

The clearance between the adjacent rings of the endless rings 11a to 11n is set to a minus (negative) clearance.

That is, the plate thicknesses of the endless rings 11a to 11n are t1 to t10, and the inner diameters in a perfect circle state are d1 to t1.
d10, when the fitting clearance is δ, d2 = d1 +
2 × t1 + δ, d3 = d2 + 2 × t2 + δ, d4 = d3
+ 2 × t3 + δ,... D10 = d9 + 2 × t9 + δ.

Next, as shown in FIG. 7, FIG. 8, FIG. 10, and FIG. The operation of the laminated ring 11 in the case of (1) will be described assuming specific dimensions.

FIG. 2 shows each of the endless rings 11a to 11n.
The cross-sectional shape is 0.2 mm thick x 9 mm wide, the inner diameter d1 of the innermost peripheral ring 11a is about 190 mm (perimeter 600 mm),
The elastic coefficient of the ring material is 1.9 × 10 ⁵ MPa, the tension acting on the entire laminated ring 11 is ⁵ kN, and the innermost ring 1
When the minimum radius of curvature of 1a was 30 mm and the fitting clearance δ between the endless rings was −2 μm, the total stress (tensile stress + bending stress) generated in each of the endless rings 11a to 11n was calculated on the desk. The results are shown in the graph.

On the other hand, FIG. 6 shows a result of a desk calculation for a conventional laminated ring. FIG. 6 shows the total stress (tensile stress + tensile stress) generated in each endless ring in the case of a laminated ring assembled with the fitting clearance δ between each endless ring being 0.
This is a result of desk-top calculation of bending stress) under the same conditions as above.

Referring to FIG. 6, in the conventional laminated ring, the tensile stress acting on each endless ring is almost equal in all the endless rings, but the bending stress is larger on the inner circumferential side. Therefore, the generated total stress becomes larger toward the inner circumference side and becomes maximum at the innermost circumference ring.

This is because, as described above, the winding radius of each endless ring constituting the laminated ring increases as the thickness of the ring increases toward the outer periphery by the thickness of the ring, so that the bending stress acting on the inner peripheral ring is reduced. This is because the bending stress acting on the outer ring is larger than the bending stress.

On the other hand, in the present laminated ring 11, as shown in FIG.
The tensile stress acting on 11n increases on the outer peripheral side, and decreases on the inner peripheral side where the bending stress is large.

That is, since the tensile stress increases on the outer peripheral side where the bending stress is small, each of the endless rings 11a to 11n
, The total stress (tensile stress + bending stress) is more uniform than in the conventional example, in other words, it is in an advantageous state in terms of durability.

Next, FIG. 3 shows the generated stress σ1 of the innermost peripheral ring 11a and the outermost peripheral ring 11a of the present laminated ring 11.
10 shows the result of a desk calculation of the relationship between the absolute value of the difference between the generated stresses σ10 of n and the fitting clearance δ between adjacent rings.
However, the sectional shape of each of the endless rings 11a to 11n,
Conditions such as the inner diameter d1 of the innermost peripheral ring 11a, the elastic modulus of the ring material, the tension acting on the entire laminated ring 11, the minimum radius of curvature of the innermost peripheral ring 11a, and the like are the same as described above.

In this case, since the absolute value of the difference between the generated stress σ1 of the innermost peripheral ring 11a and the generated stress σ10 of the outermost peripheral ring 11n becomes minimum (= 0) when δ ≒ −2 μm, the laminated ring If the fitting clearance δ between all the 11 adjacent rings is set to approximately −2 μm, the total stress generated in all the non-terminal rings 11 a to 11 n can be equalized.

On the other hand, depending on the specifications of the continuously variable transmission, the circumferential length, cross-sectional area, minimum radius of curvature, and the like of the laminated ring may differ from the present calculation conditions. The total stress (tensile stress + bending stress) generated in
Approximately the same value (standard value) regardless of the specifications of the continuously variable transmission
Therefore, in almost all of the specifications of the continuously variable transmission, by setting the fitting clearance δ between the adjacent rings of the laminated ring to approximately -2 μm, The total stress generated in the ring can be equalized.

Of course, depending on the specifications of the continuously variable transmission, the circumference of the laminated ring, the cross-sectional area (cross-sectional shape of the endless ring),
The fitting clearance δ between adjacent rings of the laminated ring may be set based on the minimum radius of curvature (when used).

Therefore, by using the present laminated ring, the total stress generated in each endless ring can be equalized, and the durability of the entire laminated ring as well as the inner peripheral ring can be greatly improved.

The fitting clearance δ between adjacent rings of the laminated ring is determined based on the circumference, cross-sectional area (cross-sectional shape of the endless ring), and minimum radius of curvature (when used) of the laminated ring.
, A clearance suitable for a continuously variable transmission can be obtained.

FIG. 4 shows a second embodiment in which the fitting clearance δ between adjacent rings of the laminated ring 11 is set in the range of 0 to −5 μm.

In this case, each of the endless rings 11a to 11
n is between 0 and -5 μm.
, But the distribution and absolute amount of each clearance are random.

FIG. 5 shows these endless rings 11a to 11a.
11n, the total stress (tensile stress + bending stress) generated in the first
Each of the endless rings 11a to 11
The cross-sectional shape of n is 0.2 mm in thickness and 9 mm in width, and the inner diameter d1 of the innermost peripheral ring 11a is about 190 mm (perimeter 600 m).
m), the elastic modulus of the ring material is 1.9 × 10 ⁵ MPa,
The table shows the results of desk calculations, where the tension acting on the entire laminated ring 11 is 5 kN, and the minimum radius of curvature of the innermost ring 11a is 30 mm.

In the laminated ring 11 of the second embodiment as well, as shown in FIG.
The tensile stress acting on 1n becomes larger on the outer peripheral side, the tensile stress decreases on the inner peripheral side where the bending stress is large, and the tensile stress increases on the outer peripheral side where the bending stress is small, so that the endless rings 11a to 11n It can be seen that the resulting total stress (tensile stress + bending stress) is in a more uniform state than in the conventional example, in other words, a more durable and advantageous state.

That is, even if the fitting clearances δ between all adjacent rings in the laminated ring 11 are not fixed, if the respective fitting clearances δ are in the range of 0 to −5 μm, each of the endless rings 11 a to It is possible to substantially equalize the total stress generated in 11n, and therefore, it is possible to improve the durability of the entire laminated ring.
Further, the manufacture of the laminated ring 11 can be facilitated.

In this case, the inner fitting clearance δ is preferably relatively negative (-2 μm or more on average).

In the second embodiment, the outer peripheral length of the inner ring before fitting (before assembling) between adjacent rings of the endless rings 11a to 11n is longer than the inner peripheral length of the outer ring.

[Brief description of the drawings]

FIG. 1 is a front view of an assembled state of a laminated ring according to a first embodiment.

FIG. 2 is a graph showing calculation results of stress acting on a lamination ring.

FIG. 3 is a graph showing a relationship between a stress difference between an innermost peripheral ring and an outermost peripheral ring and an inter-ring fitting clearance.

FIG. 4 is a graph showing an example of an inter-ring fitting clearance showing the second embodiment.

FIG. 5 is a graph showing calculation results of stress acting on a lamination ring.

FIG. 6 is a graph showing calculation results of stress acting on a conventional laminated ring.

FIG. 7 is a front view of the elements of the V-belt.

FIG. 8 is a side view of an element of the V-belt.

FIG. 9 is a front view of an assembled state of the lamination ring.

FIG. 10 is a side view of a V-belt wound between pulleys.

FIG. 11 is a top view of a V-belt wound around pulleys.

[Explanation of symbols]

 11 Laminated ring 11a-11n Non-terminal ring

Claims (5)

[Claims] 1. A laminated ring comprising a plurality of endless rings fitted and formed in a layered form, and a number of V-shaped elements which are arranged so as to be connected to each other in the circumferential direction of the laminated ring. In the V-belt for a continuously variable transmission, comprising: a clearance between adjacent rings of the laminated ring,
A V-belt for a continuously variable transmission, wherein a negative clearance is set. 2. A laminated ring comprising a plurality of endless rings fitted and formed in a layered form, and a plurality of V-shaped elements arranged so as to be able to contact each other in the circumferential direction of the laminated ring. In the V-belt for a continuously variable transmission, comprising: a clearance between adjacent rings of the laminated ring,
A V-belt for a continuously variable transmission, wherein the V-belt is set in a range of 0 to -5 [mu] m. 3. The clearance between the adjacent rings of the laminated ring is set based on the sectional shape of the endless ring, the peripheral length of the laminated ring, and the minimum radius of curvature of the laminated ring when using a belt. Or the V-belt for a continuously variable transmission according to 2. 4. A fitting clearance between adjacent rings of the laminated ring is set so that stresses generated from an innermost peripheral ring to an outermost peripheral ring of the laminated ring when the belt is used are substantially equal. 5. The V-belt for a continuously variable transmission according to item 1. 5. A laminated ring in which a plurality of endless rings are fitted to each other to form a layer, and a number of V-shaped elements which are arranged so as to be in contact with each other in the circumferential direction of the laminated ring. Wherein the outer peripheral length of the inner ring before fitting between adjacent rings of the laminated ring is equal to or longer than the inner peripheral length of the outer ring. For V-belt.