JP4573646B2 - Dry composite belt - Google Patents

Description

The present invention relates to a dry composite belt used for a belt type continuously variable transmission for automobiles and the like.

Currently, a V-belt type continuously variable transmission is being developed as a transmission for automobiles, and is partially put into practical use. Among these, the V-belt used for the dry type continuously variable transmission has an endless tension band and a fitting portion for fitting the tension band, and is locked to the tension band at equal pitch intervals in the longitudinal direction. This is a composite belt consisting of a large number of blocks. The block is composed of a core material made of metal and the like, and a resin layer that covers the surface of the core material, and the friction surface with pulleys provided on both the left and right sides of the block is formed with a resin layer, so that high load transmission A V-belt suitable for the above has been proposed.

In Patent Document 1, a convex portion is provided at the central portion in the vertical direction of one main surface of the block, and a concave portion that is fitted to the convex portion of the adjacent block is provided at the central portion in the vertical direction of the other main surface. A dry composite belt formed only on the resin layer has been proposed. By providing the concavo-convex part, the moment behavior of the block held by the pair of left and right tension bands cancels out by interfering with the concavo-convex parts of the front and rear blocks, and as a result, the heat generation of the tension band is suppressed, It has the effect of minimizing thermal degradation damage to the tension band.
However, in the case of the above structure, when the belt is bent, the concavo-convex portions are in point contact, and the resin layers are in contact with each other. Therefore, there is a problem that the heat generation suppressing effect of the tension band is lost.

Patent Document 2 proposes a dry composite belt in which a concave portion and a convex portion of a block each have a circular arc cross section.
In this case, since the concavo-convex portion is in contact with the circular arc surface, the wear is relatively small. However, since it is necessary to process not only the resin layer but also the core material in order to form the concavo-convex portion, there is a disadvantage that the processing is difficult and the cost is increased. A structure in which the concavo-convex part is provided only on the resin layer is also conceivable. However, since the fitting depth and angle are shallow, this may cause the convex part to run over the concave part, and the convex part strength decreases and the convex part. May be lost, and there is a problem that the durability of the tension band is lowered.
Japanese Patent Laid-Open No. 10-73149 Japanese Utility Model Publication No. 3-62251

SUMMARY OF THE INVENTION An object of the present invention is to provide a dry composite belt that can suppress the wear of the concavo-convex portion and ensure the strength of the bulge portion and maintain the heat generation suppressing effect of the tension band.

In order to achieve the above-mentioned object, the invention according to claim 1 has an endless tension band and a fitting part for fitting the tension band, and is locked to the tension band at equal pitch intervals in the longitudinal direction. The block includes a core material and a resin layer that covers the surface of the core material, and a convex portion is provided at the center in the vertical direction of one main surface of the block. In the dry composite belt in which a concave portion that fits with the convex portion of the block adjacent to the vertical central portion of the surface is provided, and the convex portion and the concave portion are formed in the resin layer, the resin layer is the central portion in the vertical direction of the block Is formed in the thickest resin part, and the convex part and the concave part are formed in the thickest resin part, and the convex part has a long cylindrical shape having linear upper and lower edges extending in the width direction of the block or a rectangular prismatic and collision from the surface of the resin layer in the upper and lower edge portions Flat wall is provided for, the recess is oval or rectangular shape with a straight upper and lower edge portions extending in the width direction of the block, and falls from the surface of the resin layer in the upper and lower edge portions Provided is a dry composite belt characterized in that a flat wall surface is provided, and when the belt is bent, one of the upper and lower edges of the convex portion and the upper and lower edges of the concave portion are in line contact .

As the belt wraps around the pulley and rotates, the belt is bent. At this time, since the convex portions and the concave portions of the adjacent blocks are fitted, the vertical displacement of the blocks is suppressed, and the repeated bending stress applied to the tension band can be alleviated. In particular, since the convex part is a horizontally long oblong cylinder or rectangular prism, and the concave part is also an oval or rectangular hole, when the belt is bent, the convex part and the concave part are in line contact, and the resin Even if the concavo-convex part is provided only on the layer, the wear of the convex part can be reduced and the occurrence of rattling can be suppressed.
In addition, since the contact part of the uneven part of the long cylindrical shape or rectangular prism shape increases compared to the cylindrical shape, the vertical dimension can be reduced compared to the conventional cylindrical shape, and the height of the convex part is the same However, the concave / convex fitting depth can be increased. As a result, the vertical movement of the block can be further suppressed, and the stress applied to the tension band can be reduced.

As is apparent from the above description, according to the first aspect of the present invention, a horizontally long long cylindrical or rectangular prismatic convex portion is provided on one main surface of the block, and the convex portion is fitted on the other main surface. Since the oval or rectangular hole is provided, the convex portion and the concave portion come into contact with each other when the belt is bent, and wear of the convex portion made of the resin layer can be reduced, and the occurrence of rattling can be suppressed. Moreover, since the convex portion is not a conventional hemispherical convex portion, the fitting depth and angle of the concave and convex portions can be increased, the strength of the convex portion can be ensured, and the heat generation suppressing effect of the tension band can be maintained.

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

As shown in FIGS. 1 to 3, the dry composite belt A includes a plurality of blocks 1 in which a pair of left and right fitting grooves 2 are formed on both sides, and each of the pair of fitting grooves 2 has an endless shape. The plurality of blocks 1 are engaged with each other at a constant pitch in the longitudinal direction by a pair of tension bands 10. A plurality of endless core wires 11 are embedded in the rubber part of the tension band 10 in parallel in the width direction.

The block 1 is composed of a metal core 1a that is a core material and an abrasion-resistant resin layer 1b that covers the periphery of the core. At least both side surfaces 3 that contact the pulley are resin layers 1b. It is covered. On the upper and lower inner surfaces of the fitting groove 2, protrusions 4, 5 called cogs are continuously provided from the back of the fitting groove 2 toward the opening, and these protrusions 4, 5 are provided on the surface of the tension band 10. By engaging the concave grooves 12 and 13 formed on the back surface, the block 1 is locked at an equal pitch in the belt longitudinal direction. Here, the upper protrusion 4 has a square cross section, and the lower protrusion 5 has an arc of a cross section.

The block 1 of this embodiment is thickest at the central portion in the vertical direction, and is gradually thinned toward the upper and lower end portions. A line 6 indicates a ridge line provided at the center pillar portion at the center in the width direction of the block 1. A concave portion 7 is formed in the central portion of the main surface of the block 1 in the vertical direction (center pillar portion), and is fitted into the concave portion 7 of the block 1 adjacent to the central portion of the other main surface in the vertical direction (center pillar portion). Protrusions 8 are formed. The concave portion 7 and the convex portion 8 are formed only in the resin layer 1b. The convex portion 8 is a horizontally long oblong column extending in the width direction of the block 1, and the concave portion 7 is also an oval hole into which the convex portion 8 can be fitted. A mountain ridge portion 8 a is provided at the center in the vertical direction of the convex portion 8. The adjacent blocks 1 are positioned in the vertical and horizontal directions by the fitting of the uneven portions 7 and 8.

Here, the effect | action of the recessed part 7 and the convex part 8 is demonstrated with reference to FIG. 4, FIG.
4A shows a fitting state of the uneven portion when the belt is not bent, and FIG. 4B shows a fitting state of the uneven portion when the belt is bent.
When the belt is not bent, the ridge portion 8 a of the convex portion 8 is in contact with the bottom surface of the concave portion 7. Since the adjacent blocks 1 are relatively inclined when the belt is bent, the upper and lower edges 7 a of the recess 7 come into contact with the upper and lower edges 8 b of the protrusion 8.

As shown in FIG. 5 (a), in the case of the columnar convex portion 20, the upper and lower edge portions 21 are substantially point-contacted with the concave portion as shown by a broken line, whereas FIG. In the case of the horizontally long long cylindrical convex portion 8, the upper and lower edge portions (straight line portions) 8 b are in line contact with the edge portion 7 a of the concave portion 7 as indicated by broken lines. That is, since the contact area is longer than that of the cylindrical convex portion 20, even if the belt is repeatedly bent, wear of the contact portion is reduced.

In FIG. 4, an example has been described in which one of the upper and lower edges 7 a of the concave portion 7 contacts the upper and lower edges of the convex portion 8 when the belt is bent, but the apex angle of the ridge portion 8 a of the convex portion 8 is the ridgeline of the block 1 If it is larger than the apex angle at 6, the upper or lower edge of the top surface of the convex portion 8 contacts the bottom surface of the concave portion 7 when the belt is bent. Also in this case, since the linear portion 8b of the convex portion 8 is in line contact with the bottom surface of the concave portion 8, wear is reduced.

FIG. 6 shows the convex portion 8 of the first embodiment and the convex portion 8 ′ of the second embodiment in comparison.
6A shows the long cylindrical projection 8 of the first embodiment shown in FIG. 5B, and FIG. 6B shows the second embodiment in which the vertical width is shortened. A long cylindrical convex portion 8 'is shown. When the width dimensions in the vertical direction are W1 and W2, respectively, and the lengths of the straight portions 8b are L1 and L2, respectively, they are set as follows. In addition, the protrusion heights H1 and H2 of both convex parts 8 and 8 'are equal.
W1> W2
L1 <L2
H1 = H2

FIG. 7 shows a fitting state of the two types of convex portions 8 and 8 ′ with the concave portions 7 and 7 ′.
In the case of the convex portion 8 having a wide width dimension W1, as shown in FIG. 7 (a), the fitting depth D1 with the concave portion 7 is shallow, whereas in the convex portion 8 ′ having a narrow width dimension W2, The fitting depth D2 with the recess 7 ′ is deepened.
D1 <D2
Thus, even if the protrusion heights H1 and H2 of the protrusions are the same, the fitting depth D2 with the recess 7 can be increased and the straight line portion L2 can be increased by reducing the vertical width W2. . Therefore, the vertical movement of the block 1 can be more effectively suppressed.
In the case of the convex portion 8 ′, the strength is lower than that of the convex portion 8 due to the narrow width dimension W 2, but the length in the lateral direction is smaller than that of the cylindrical convex portion (see FIG. 5A). Since it is long, there is no possibility that the convex portion 8 'will break.

FIG. 8 shows the convex portion 8 of the first embodiment and the convex portion 8 ″ of the third embodiment in comparison.
In the first and second embodiments, the convex portion and the concave portion have a horizontally long and long cylindrical shape. However, if the shape has a linear portion at the top and bottom, it has a substantially rectangular column shape as shown in FIG. Also good. In the case of the substantially rectangular columnar convex portion 8 ″, even if the width dimensions W1 and W3 are the same, the length L3 of the straight portion 8b is longer than that of the long cylindrical convex portion 8, and therefore the contact pressure per unit length. Can be reduced, and wear can be further suppressed.

The present invention is not limited to the above embodiments.
Although the example which has the ridge part 8a in the center part of the convex part 8 was demonstrated in the said Example, what the convex part 8 does not have a ridge part, ie, a top surface may be flat. In the case of a convex portion that does not have a ridge portion when the belt is bent, one of the upper and lower edges of the top surface of the convex portion 8 contacts the bottom surface of the concave portion 7. Also in this case, since the straight portion 8b of the convex portion 8 is in line contact with the bottom surface of the concave portion 8 as described above, wear is reduced.
Further, the example in which the central portion in the vertical direction of the block 1 has the thickest structure has been described. This is, for example, pressed by a tension roller from the outside of the belt as described in Japanese Patent Nos. 3267596 and 3290647. Thus, the structure is suitable for a continuously variable transmission that obtains belt tension. That is, the structure is suitable when the direction of bending along the pulley and the direction of bending along the tension roller are opposite. On the other hand, in the case of a composite belt used in a continuously variable transmission that does not press from the outside with a tension roller, a block having a shape in which the thickness of the lower half is thinner than the upper half may be used.

It is a one part perspective view of the dry type composite belt concerning this invention. It is the front view, back view, and side view of the block concerning this invention. It is sectional drawing of the block concerning this invention at the time of belt bending. It is an expanded sectional view of the uneven | corrugated | grooved part at the time of the non-bending of a belt, and a bending. It is a front view which compares and shows the conventional cylindrical convex part and the long cylindrical convex part concerning this invention. It is a front view which contrasts and shows the 1st Example and 2nd Example of the convex part concerning this invention. It is sectional drawing of the state which two convex parts shown in FIG. 6 fitted with the recessed part. It is a front view which compares and shows the 1st Example and 3rd Example of the convex part concerning this invention.

Explanation of symbols

A Dry composite belt 1 Block 1a Core 1b Resin layer 2 Fitting groove 7 Recess 8 Protrusion 8a Ridge 8b Straight line

Claims (1)

It has an endless tension band and a plurality of blocks that have a fitting portion that fits the tension band and is locked to the tension band at equal pitch intervals in the longitudinal direction.
The block includes a core material and a resin layer covering the surface of the core material,
A convex portion is provided at the center in the vertical direction of one main surface of the block, and a concave portion is provided that fits with the convex portion of the adjacent block at the central portion in the vertical direction of the other main surface. In the dry composite belt formed in
The resin layer is formed so that the central part in the vertical direction of the block is the thickest,
The convex part and the concave part are formed in the thickest resin part,
The convex portion has a long cylindrical shape or a rectangular prism shape with straight upper and lower edges extending in the width direction of the block , and a flat wall surface protruding from the surface of the resin layer is provided on the upper and lower edges. And
The concave portion is an oval shape or a rectangular shape having linear upper and lower edges extending in the width direction of the block , and the upper and lower edges are provided with flat wall surfaces that fall from the surface of the resin layer,
A dry composite belt characterized in that when the belt is bent, one of the upper and lower edges of the convex portion and the upper and lower edges of the concave portion are in line contact .

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