JPH0237307Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field]

The present invention relates to a drive belt for a belt-driven continuously variable transmission.

[Conventional technology]

A belt-driven continuously variable transmission is one type of automatic transmission for automobiles. This continuously variable transmission is generally
For example, as shown in FIG. 7, a pair of endless metal hoops 10 and a circumferential direction
The drive belt A includes a plurality of metal V-blocks 20 that are movably incorporated in a continuous manner, and the drive belt A rotates steplessly between the drive pulley 30 and the driven pulley 40. It is now possible to move by proportion. The drive belt A has a hoop 1 with a circumference of several hundred millimeters.
It is manufactured by sequentially mounting V-blocks 20 formed with a tolerance of several microns to zero. However, during installation, a gap between the blocks inevitably remains, and if the gap between the blocks is too large, it reduces the durability of the belt and reduces the transmission efficiency. It is a common practice to incorporate several adjusting blocks of different thicknesses from the standard block inside the block to minimize the gap between the blocks (for example, Utility Model Application No. 78694/1983).

[Problem that the invention attempts to solve]

However, because the adjustment blocks imported in this way have different thicknesses, it is necessary to use different manufacturing lots from the standard blocks, so it is unavoidable that slight differences in dimensions will occur due to variations in the lots. However, when this difference occurs in the plate width direction, there is a problem in that the durability of the drive belt decreases. That is, due to lot variations, for example, the eighth
As shown in FIG. A, when the width of the adjustment block 21 is formed wider than the width of the standard block 20, when the adjustment block 21 is bitten by the pulleys 30 and 40,
Since the adjustment block 21 is pressed toward the outer circumferential side Y as shown in FIG. 2B, excessive bending stress is generated in the hoop 10. This bending stress is caused by the drive belt A
If the total number of adjustment blocks 21 is N, as shown by the arrow in FIG. become.

[Purpose of invention]

The present invention was developed in view of such conventional problems, and it is possible to minimize the negative effects even if the width dimension of the adjustment block is different from the width dimension of the standard block. An object of the present invention is to provide a drive belt for a step-change transmission.

[Means to solve the problem]

The present invention consists of an endless hoop and a plurality of V-blocks that are movably built into the hoop in succession in the circumferential direction thereof, and for adjusting the gap between the blocks in the V-block. In a continuously variable transmission drive belt including a plurality of adjusting blocks, the above object is achieved by incorporating at least two or more of the plurality of adjusting blocks in succession. Further, in the embodiment of the present invention, the above object is most effectively achieved by incorporating all of the plurality of adjustment blocks in series at one location on the belt.

[Effect]

The present invention recognizes the fact that the width of the adjustment block differs from the width of the standard block due to lot variations as an unavoidable fact, and attempts to minimize this effect. This method focuses on the fact that since the adjustment blocks have the same lot, there is no variation in width, and at least two or more adjustment blocks are successively assembled. As a result, the number of locations where bending stress occurs can be significantly reduced around the entire circumference of the drive belt.
Furthermore, since at least one side of the adjusting block is at the same height, the absolute value of the bending stress generated can be kept low, and the durability of the drive belt, especially its hoop, can therefore be improved.

【Example】

Embodiments of the present invention will be described in detail below based on the drawings. FIGS. 5 and 6 show the main parts of a belt-driven continuously variable transmission for an automobile incorporating a drive belt according to an embodiment of the present invention. In the figure, reference numeral 100 is an input shaft, and 102 is an output shaft, and the input shaft 100 is connected to an engine (not shown). A V-shaped pulley 104 is attached to the input shaft 100. This V-shaped pulley 104 includes a fixed pulley 106 fixed to the input shaft 100 and a movable pulley 108 movable in the axial direction of the input shaft 100. The movable pulley 1
A cylinder piston mechanism 110 fixed to the input shaft 100 is provided behind the input shaft 08. The cylinder piston mechanism 110 includes a movable pulley 10
A hydraulic chamber (not shown) is formed between the cylinder and the cylinder 8.
The fixed pulley 106 and the movable pulley 108 are attached with their respective inclined surfaces 106A and 108A facing each other.
The space between them is a V-groove 112. When hydraulic pressure is supplied to and discharged from the hydraulic chamber by the action of the cylinder-piston mechanism 110, the movable pulley 108 moves relative to the fixed pulley 106, and the width of the V-groove 112 changes. On the other hand, a V-shaped pulley 118 is also attached to the output shaft 102, and includes a fixed pulley 114 fixed to the output shaft 102 and a movable pulley 116 movable with respect to the output shaft 102. The width of the V-groove 122 between the fixed pulley 114 and the movable pulley 116 can be widened or narrowed by a cylinder piston mechanism 120 provided behind the pulley 116. A drive belt 124 is wound between the V-groove 112 of the V-shaped pulley 104 on the driving side and the V-groove 122 of the V-shaped pulley 118 on the driven side. This drive belt 124 includes a pair of endless hoops 126,
It consists of a plurality of V blocks 128 that are movably and consecutively incorporated into the hoop 126 in its circumferential direction, and a standard V block 128s is installed in the V block 128 to adjust the gap between the V blocks. This includes a plurality of adjusting V blocks 130 formed to have different thicknesses. The V block 128 (including the adjustment block 130; the same applies hereinafter) is a metal member, and the main body portion 13 has tapered side surfaces 132, 132.
4, a square rod-shaped connecting portion 136 that projects vertically upward from the center of the upper surface of the main body 134, and a supporting portion 138 that is formed parallel to the upper surface of the main body 134 at the upper end of the connecting portion 136. Consisting of
Further, this V block 128 is connected to the connection portion 136.
on both sides of the body portion 134 and the upper surface of the support portion 138
A pair of hoop grooves 140, 140 are provided between the hoop grooves 140, 140 and the hoops 126, 126 are inserted into and assembled into the pair of hoops 126, 126 through the hoop grooves 140, 140. This embodiment thus provides a large number of standard blocks 128s and adjustment blocks 13 for both hoops 126, as shown in FIGS.
0, the plurality of adjustment blocks 130
All of the parts are continuously installed in one place on the belt. Next, the operation of this embodiment will be explained. Standard block 128s and adjustment block 130
For example, if the width W of the adjustment block 130 increases by ΔW due to the variation in the lot,
This adjustment block 130 is connected to the V-shaped pulley 104,1
It is placed in the 18 V grooves 112, 122 and protrudes from the standard block 128s by ΔW/2tanθ in the radial direction. In this way, V-type pulley 1
04 and 118, a large inflection point occurs in the hoop 126, but conventionally, as shown in FIG. Because it was inserted in 128, the third
As shown by the broken line in the figure, extremely sharp bending stress was generated on the surface of the hoop 126 in the area where the adjustment block 130 was present. however,
In this embodiment, a plurality of adjustment blocks 130
Since all of the parts are continuously installed in one place, the number of places where bending stress is generated is reduced to only two places, and the absolute value of the bending stress is also suppressed to a small value. FIG. 4 shows the results of an experiment regarding this point.
Figure A shows a case in which the adjustment blocks 130 are inserted separately, and Figure B shows a case in which the adjustment blocks 130 are inserted successively at one location.
As is clear from this figure, when inserted separately, the frequency of bending stress corresponding to the 75.0 to 77.5Kg/ ^mm2 category is highest, and the maximum bending stress is
It has reached 117.449Kg/mm ² . On the other hand, when the adjustment blocks 130 are assembled in one place, the frequency of bending stress corresponding to 72.5 to 75.0 is the highest, and the maximum bending stress is
It can be seen that it has decreased to 95.1339Kg/mm ² . In this way, the frequency of bending stress is biased towards the lower side,
Moreover, the low maximum bending stress means that the hoop 12
This means that the bending stress burden of No. 6 is small, which means that it is more advantageous in terms of durability. In addition, in the above embodiment, adjustment block 1
All 30 parts were installed in one place in succession, but in this invention, it is not necessary to concentrate on only one place, and in some cases, it is possible to incorporate them in two places. It's not a hindrance.

[Effect of the idea]

As explained above, according to the present invention, the width dimension of the adjusting block is formed differently from the width dimension of other standard blocks due to the difference in lot, and as a result, the adjusting block has a radius different from that of the other standard blocks. Even if a phenomenon that shifts in direction occurs, an excellent effect can be obtained in that the influence can be minimized.

[Brief explanation of the drawing]

Fig. 1 is a front view showing an embodiment of the drive belt for a continuously variable transmission according to the present invention, Fig. 2 is an enlarged view of the portion indicated by the arrow in Fig. 1, and Fig. 3 is a hoop surface in the above embodiment. Figures 4A and B are diagrams showing the experimental results of bending stress vs. frequency in the conventional and above-mentioned embodiments, respectively. Figure 5 is a diagram showing the bending stress in comparison with the conventional one. FIG. 6 is an enlarged sectional view taken along the line of FIG. 5, and FIG. A perspective view showing the transmission, Figures 8A and B are diagrams for explaining the effect when the adjustment block is formed wider than the standard block, and Figure 9 is a diagram for explaining the effect when the same effect is performed. FIG. 104,118...V-type pulley, 112,12
2...V groove, 126...hoop, 128...V block, 128s...standard block, 130...
Adjustment block, 140... hoop groove.

Claims (1)

[Claims for Utility Model Registration] (1) An endless hoop, and a plurality of Vs that are movably built into the hoop in a continuous manner in the circumferential direction.
In the drive belt for a continuously variable transmission, the V-block includes a plurality of adjustment blocks for adjusting the gap between the blocks, the plurality of adjustment blocks being at least two or more. A drive belt for a continuously variable transmission, characterized in that it is assembled in a continuous state. (2) The drive belt for a continuously variable transmission according to claim 1, wherein all of the plurality of adjustment blocks are successively assembled at one location on the belt.