JP2001090786A - Heavy load transmission v belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heavy load transmission V belt realizing high dimensional accuracy, reducing noise at traveling time and being excellent in durability. SOLUTION: This heavy load transmission V belt has an endless tension belt and a large number of same-shaped blocks 7 being locked on and fixed to the tension belt at plural kinds of pitches by being juxtaposed in the belt lengthwise direction and arranging a contact part for contacting with a pulley groove on a belt width directional side surface. The respective blocks 7 have an engaging projection 13 arranged on a belt lengthwise directional one surface and an engaging hole 14 arranged on the other surface, and has a reinforcing member 12 embedded so that the engaging projection 13 of one block 7 of a pair of mutually adjacent blocks 7 engages with the engaging hole 14 of the other block 7 and the thickness center is positioned on the engaging projection 13 side more than the thickness center of the whole block 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a high-load transmission V-belt.

[0002]

2. Description of the Related Art For example, as disclosed in Japanese Utility Model Laid-Open No. 1-55344, Japanese Utility Model Laid-Open No. 6-69490 and Japanese Patent Laid-Open No. 5-272595, a large number of resin blocks are connected to a rubber tension band. A high-load transmission V-belt locked and fixed using an uneven meshing structure of a block and a tension band has been developed for many years. For example, two V-belts including a fixed sheave and a movable sheave, a driving side and a driven side, are provided. It is used in the field of a continuously variable transmission wound around a speed change pulley.
With this type of V-belt,
The fixing of each block to the tension band is performed not by bonding but by a physical locking state (meshing state).
Specifically, this V-belt is provided with a pair of left and right tension bands a, a arranged in the belt width direction, as shown in the cross-section of the belt in FIG. As shown in the figure, upper and lower concave portions e, e,... And lower concave portions f, f,. It is provided. On the other hand, as shown in FIG. 8 (c), a pair of left and right fitting portions h, notched grooves for locking the tension bands a, a on the belt width direction side portion of each block g, respectively. h is formed, and an upper convex portion i as an upper meshing portion is formed on the upper surface of each fitting portion h.
In addition, lower projections j are provided on the lower surface as lower engagement portions, respectively. Then, the tension bands a, a are press-fitted into the right and left fitting portions h, h of the blocks 7, respectively, and the blocks g are locked and fixed to the tension bands a, a.

In the V-belt, the mesh thickness (t ₂ ) of the tension band a is set to be larger than the mesh gap (t ₁ ) of the block g, and the tension band a is compressed in the thickness direction. An interference is provided so as to be inserted and fitted into the fitting portion h of g. The play between the tension band a and the block g is maintained at a necessary level by an initial interference (s = t ₁ -t ₂ ) provided at the time of assembling the belt. Try to suppress fatigue. Further, as shown in FIG. 8 (a), there is provided a protrusion k in which the tension band a protrudes from the side surface of each block g by about 100 μm. Noise can be reduced.

[0004] In order to maintain the effect of noise reduction by the extra k even after the belt has been running for a long time, as shown in Japanese Utility Model Application Laid-Open No. 5-17517, the extra k is required.
And the rubber elastic modulus is increased, the depth abutting angle (α) of the tension band a fitted to the block g is optimized as proposed in Japanese Patent Application No. 10-290829, Improvements have been made such as buffing the contact surface of the pulley of the belt a to suppress the heat generation of the belt and minimize the dimensional change over time of the run-out k. These improvements were effective in suppressing the temporal change of noise in the initial stage of belt running. That is, if the generation k is maintained,
The noise could be reduced accordingly.

However, in the process of running the belt, the resin of the block g and the protrusion k of the tension band a are competitively worn, the protrusion amount of the protrusion k gradually decreases, and the noise increases. The belt of the shape and the material will emit a certain level of noise soon. The noise in the latter half of the belt running is caused by the pitch sound when the pulley enters or comes off the block g due to the limit of the buffering effect on the pulley entry of the block due to the rise k.

In order to solve the problem of the pitch sound, as described in Japanese Utility Model Laid-Open Publication No. Sho 62-96146 and Japanese Patent Laid-Open Publication No. Hei 7-305745, the pitch at which the blocks are attached to the tension band is fixed. Randomly mixed blocks with chamfered edges at the entrance of the pulley,
An attempt was made to randomize the pitch at which the block enters the pulley.

[0007]

However, since the resin surface on which the block receives the surface pressure of the pulley is located at the position where the reinforcing member exists, the pitch sound of the block is not largely dispersed and the contact area of the block with the pulley is reduced. for,
There is a problem that the resin constituting the block is worn and the resin is chipped. Furthermore, it is necessary to manufacture blocks of different shapes with different molds. If the meshing gap of the blocks, the block pitch width or the block angle varies, the above-mentioned tightening allowance and protrusion allowance are increased.
It is conceivable that the surface pressure may vary within the book, the surface pressure from the pulley applied to the block becomes uneven, and the durability reliability of the belt is hindered.

Therefore, it is desirable to use a block of a single shape as a means for reducing the noise during running of the belt. As such a means, there is a technique in which a plurality of types of mounting pitches of the block to the tension band are used, that is, a plurality of types of pitches of the upper and lower concave portions of the tension band.

In order to increase the strength of the block, the block is formed of a resin in which a reinforcing member having a high elastic modulus is buried at a substantially central position in the thickness direction of the block. For example, as shown in a side cross-sectional view of the center in the belt width direction in FIG. 9, an engagement protrusion 1 is provided at a position substantially at a belt pitch line on one surface in the belt length direction of each block g, and is provided on an opposite surface. Are provided with engaging holes m, respectively, and when the blocks g are mounted on the tension band at an equal pitch, the displacement of the blocks g in the vertical and horizontal directions is restricted by their engagement.
The engaging projection 1 and the engaging hole m are formed of resin. As described in Japanese Patent Application Laid-Open No. 10-73149, the engaging hole m is formed in the reinforcing member n where these are formed.
In order to secure the shear strength of the engagement projections 1 while maintaining the strength without making a hole or the like for forming the holes, they are formed in a truncated cone shape or a truncated hemisphere shape.

[0010] If the above-mentioned method of using a plurality of types of mounting pitches of the block g to the tension band is attempted with the block g having the above configuration, the following problem occurs. That is, FIG. 10 shows the positional relationship of the block g when the block g is randomly attached to the tension band at a pitch of p ₁ (small pitch) and p ₂ (large pitch). Is provided at the center in the thickness direction, so that the depth of the engagement hole m cannot be increased, so that the height of the engagement protrusion 1 is low and the pitch is p ₂ (large pitch).
In this case, the engagement of the engagement projection 1 with the engagement hole m is no longer possible, and the displacement of the block g is no longer restricted. If the effect of restricting the displacement of the block g is lost, the block g enters the pulley irregularly, causing vibration and wear, and significantly lowering the durability of the belt. Here, it is conceivable to combine two types of blocks having different heights of the engagement protrusions. However, the engagement relationship between the block and the tension band, the block pitch width or angle within one belt, and the like, are several tens of. Since high dimensional accuracy on the order of μm is required, it is difficult to realize the dimensional accuracy by forming the belt with two types of blocks.

SUMMARY OF THE INVENTION The present invention has been made in view of the foregoing, and an object of the present invention is to provide a high-load transmission V-belt which realizes high dimensional accuracy, has low running noise, and has excellent durability. It is in.

[0012]

SUMMARY OF THE INVENTION The present invention achieves high dimensional accuracy by using a block of a single shape, and reduces noise during belt running by attaching the block to a tension band at a plurality of types of pitches. The height of the engaging projections and the depth of the engaging holes are sufficiently ensured so that the engagement between the engaging projections and the engaging holes for regulating the displacement of the block is effective even at a large pitch. The burial position of the reinforcing member is positioned closer to the engagement protrusion than the center of the thickness of the block so that the durability of the belt is enhanced.

More specifically, the invention of the present application relates to an endless tension band, a plurality of types of pitches arranged side by side in the belt length direction in the tension band, and a pulley groove formed on a side surface in the belt width direction. A high-load transmission V-belt comprising a plurality of blocks of the same shape provided with contact portions that come into contact with each other, wherein each of the blocks includes an engagement protrusion provided on one surface in a belt length direction and the other. And an engagement hole provided on the surface of the block, an engagement protrusion of one of the pair of blocks adjacent to each other is engaged with an engagement hole of the other block, and the center of thickness is the entire block. A reinforcing member buried so as to be located closer to the engagement protrusion than the center of the thickness.

According to the above configuration, since the belt is formed of a single-shaped block, variations such as the meshing gap of the block, the interference, and the allowance can be minimized. The dimensional accuracy is good, and the surface pressure from the pulley on the block is uniform, so that the durability durability of the belt is also excellent.

Further, since the blocks are locked and fixed to the tension band at a plurality of kinds of pitches, the pitch sound of the blocks generated when the belt is run is dispersed at a plurality of frequencies, and the pitch sound is generated when the belt runs. Noise can be reduced.

Here, the ratio of the difference between the maximum pitch and the minimum pitch to the minimum pitch among the plurality of types of block pitches is preferably 5 to 20%. Various studies have been made on whether a pitch shifted from the pitch with reference to a certain pitch (for example, 3.0 mm) can reduce the noise peak of the pitch frequency and reduce the noise. As a result, when the difference between the maximum pitch and the minimum pitch is less than 5% of the minimum pitch (for example, when the minimum pitch is 3.0 mm and the maximum pitch is less than 3.15 mm), noise reduction during belt running is reduced. The effect is small and 10% (for example, the minimum pitch is 3.
When the distance is 0 mm, the maximum pitch is 3.3 mm). On the other hand, if the pitch is larger than 20% (for example, when the minimum pitch is 3.0 mm and the maximum pitch is larger than 3.6 mm), the total number of blocks is reduced, and a portion where the large pitch continues is a large force on the pulley. (The shared power per block increases), resulting in sacrificing high load durability. Further, when the belt is bent at a large pitch portion, the core wire is bent greatly in a polygonal manner, and the bending fatigue resistance of the core wire is also sacrificed. From the above viewpoint, the ratio of the difference between the maximum pitch and the minimum pitch to the minimum pitch is preferably 5 to 20%, and
It is even better to set it to 3%. Furthermore, the engagement protrusion provided in each block engages with the engagement hole of the adjacent block, whereby the displacement of the block in the vertical and horizontal directions is restricted,
As a result, the block smoothly enters the pulley, and vibration and wear of the block are suppressed. Here, since the thickness center of the reinforcing member embedded in the block is located closer to the engagement protrusion than the thickness center of the entire block, the depth of the engagement hole provided in the block is limited. Can be relaxed and this can be increased,
Accordingly, the height of the engagement protrusion can be increased.
Therefore, the engagement of the engagement projection with the engagement hole is effectively performed even in a portion where the pitch between the blocks is large. In this case, the thickness of the entire block refers to the maximum diameter of the block thickness excluding the engagement protrusion.

In order to obtain a belt that can withstand high torque by increasing the block strength, it is desirable that the thickness of the reinforcing member be as large as possible. For high-load transmission that satisfies all of high dimensional accuracy, durability and low noise by means of mounting a single-shaped block at multiple pitches to the tension band while ensuring displacement control in the vertical and horizontal directions between them. A V-belt can be obtained.

Here, the engaging projection may have a truncated conical or hemispherical shape. If the engaging projection is increased to increase the shear strength, it is necessary to make the engaging hole deeper, and in some cases, it is necessary to drill a hole in the reinforcing member. By doing so, it is possible to increase the shear strength of the engagement projections, and to provide the engagement holes with which the engagement projections are engaged without reducing the strength by drilling holes in the reinforcing member.

Further, a portion on the inner peripheral side of the belt from the engaging projections or the engaging holes on both surfaces of the block is formed as an inclined surface which is inclined toward the center of the block thickness toward the inside of the belt. The configuration may be such that the inclination angle of the engagement hole side is larger than that of the engagement projection side. Such an inclined surface is necessary to avoid contact between the blocks when the belt is wound around the pulley, but the reinforcing member embedded in the block is positioned closer to the engagement protrusion than the center of the block thickness. Therefore, the inclination angle of the inclined surface that can be provided on the engagement protrusion side must be small. Therefore, by making the inclined surface on the engagement hole side larger than the engagement protrusion side as in the above configuration, the shortage of the inclination angle on the engagement protrusion side is compensated for by the inclination angle on the engagement hole side. Therefore, contact between the blocks is avoided.

In this case, the block is provided with a fitting portion into which the tension band is press-fitted and fitted. The upper engaging portion is provided on the upper surface of the fitting portion, and the upper engaging portion is provided on the lower surface. The lower meshing portion formed of a ridge having a symmetrical cross section in the thickness direction of the block opposed to the portion is formed,
The tops of the upper and lower meshing portions of the block may be configured so as to be shifted from the center of the thickness of the entire block so that the heights of both ends in the block thickness direction of the lower meshing portion from the block lower end are substantially the same. . If the inclination angle between the inclined surface on the engagement projection side and the inclined surface on the engagement hole side is different as described above, when the block thickness center of the upper and lower meshing portions and the thickness center of the entire block are matched, the protrusion There is a difference in height from the block lower end at both ends in the block thickness direction of the lower meshing portion composed of, and imbalance occurs in a fitting state with a tension band or a bending state of the belt. By displacing the center of the block thickness of the portion and making the heights of both ends of the protrusion from the lower end of the block substantially the same, such imbalance does not occur.

[0021]

As described above, according to the present invention, the belt is formed by a block having a single shape.
Variations such as the meshing gap of the blocks can be minimized, and the dimensional accuracy of the belt is good, and the surface pressure from the pulley applied to the block is uniform, so the durability durability of the belt Will also be excellent.

Further, since the blocks are locked and fixed to the tension band at a plurality of types of pitches, the pitch sound of the blocks generated when the belt is run is dispersed at a plurality of frequencies, and the pitch noise is generated when the belt runs. Noise can be reduced.

Further, since the engaging projections provided on each block engage with the engaging holes of the adjacent blocks, the displacement of the blocks in the vertical and horizontal directions is regulated, whereby the blocks smoothly enter the pulley. As a result, vibration and wear of the block are suppressed. Here, since the thickness center of the reinforcing member embedded in the block is located closer to the engagement protrusion than the thickness center of the entire block, the depth of the engagement hole provided in the block is limited. Therefore, the height of the engaging projection can be increased. Therefore, the engagement of the engagement projections with the engagement holes can be effectively applied even in a portion where the pitch between the blocks is large. In order to obtain a belt that can withstand high torque by increasing the block strength, it is desirable that the thickness of the reinforcing member is as thick as possible. However, according to the present invention, the strength between the blocks is reduced without lowering the block strength as compared with the conventional block. A high-load transmission V that satisfies all of high dimensional accuracy, durability and low noise by means of mounting a block of a single shape at a plurality of pitches in a tension band while ensuring displacement control in the vertical and horizontal directions. You can get a belt.

[0024]

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

(Embodiment 1) FIG. 1 shows Embodiment 1 of the present invention.
1 shows a high load transmission V-belt B according to the present invention.
Consists of a pair of left and right endless tension bands 1, 1 and a large number of blocks 7, 7,... Which are continuously locked and fixed to the tension bands 1, 1 in the belt length direction.

As shown in FIG. 2, each tension band 1 has a plurality of high-strength, high-modulus core wires 1b, 1b,... (Core body) made of aramid fiber or the like inside a shape-retaining layer 1a made of hard rubber. ) Are spirally arranged and buried, and on the upper surface of each tension band 1, groove-shaped upper concave portions 2, 2, as upper engaged portions extending in the belt width direction corresponding to the respective blocks 7. But,
On the lower surface, lower concave portions 3, 3, as lower engaged portions extending in the belt width direction corresponding to the upper concave portions 2, 2,.
Are formed respectively. The upper concave portion 2 and the lower concave portion 3 have a plurality of types of pitches (for example, 3.0 mm).
And 3.3 mm) are provided so as to appear randomly along the length direction of the tension band 1, and the ratio of the difference between the maximum pitch and the minimum pitch to the minimum pitch is 5 to 20%. Further, canvases 4 and 4 are adhered to the upper and lower surfaces of the tension band 1 for the purpose of improving the wear resistance and the like.

The hard rubber which forms the shape-retaining layer 1a is heat-resistant by, for example, mixing H-NBR rubber reinforced with zinc methacrylate with short fibers such as aramid fibers and nylon fibers to strengthen the rubber. It is considered to be excellent and hard to be permanently deformed. The hardness of the hard rubber requires a rubber hardness of 75 ° or more as measured by a JIS-C hardness tester.

On the other hand, each block 7 is composed of upper and lower beams 7a and 7b extending in the belt width direction (left and right direction) and a center pillar 7c connecting the left and right central portions of both beams 7a and 7b up and down. It is formed in a substantially H shape. Notched groove-shaped fitting portions 8, 8 opened on the left and right sides in the belt width direction are formed so as to be surrounded by the upper and lower beams 7a, 7b and the center pillar 7c. Then, the tension bands 1 are detachably fitted to the fitting portions 8 in the width direction. The surfaces of the upper beam 7a and the lower beam 7b that form the side surfaces of the block 7 are respectively an upper contact portion 11a and a lower contact portion 11 that contact the pulley groove surface (not shown) of the V pulley.
b. Further, the belt angle formed by the left and right side surfaces of the block 7 is the same as the angle of the pulley groove surface. By press-fitting the tension bands 1 and 1 into the fitting portions 8 and 8 of each block 7, respectively, the blocks 7 are continuously inserted into the tension bands 1 and 1 in the belt length direction. Fixed.

That is, as shown in FIG. 3A, the upper wall surface of each fitting portion 8 in each block 7 has a projection as an upper meshing portion meshing with each upper concave portion 2 on the upper surface of the tension band 1. An upper convex portion 9 formed of a ridge, and a lower portion formed of an arc-shaped projecting ridge on a lower wall surface of the fitting portion 8 as a lower meshing portion meshing with each lower concave portion 3 on the lower surface of the tension band 1. Convex part 10
Are formed in parallel with each other, and the upper and lower convex portions 9 and 10 of each block 7 are engaged with the upper and lower concave portions 2 and 3 of the tension band 1 so that the blocks 7, 7,. The tension bands 1 and 1 are locked and fixed by press-fitting in the belt length direction, and in this locked state, both the outer side surface of each tension band 1 and the contact portion 11 which is the side surface of each block 7 contact the pulley groove surface. And the upper and lower protrusions 9 of the block 7,
Power is transmitted and received by meshing of the upper and lower concave portions 2 and 3 (meshed portions) of the tension bands 1 with the meshing portions 10 (meshed portions). In this manner, the V-belt B is formed by locking and fixing a large number of blocks 7, 7,... To the pair of tension bands 1, 1 at a plurality of types of pitches in the belt length direction.

Each of the blocks 7 is made of a hard resin material, and has a reinforcing member 12 made of a lightweight aluminum alloy or the like embedded therein. The reinforcing member 12 includes, for example, upper and lower protrusions 9 and 10 (meshed portions with the tension band 1) and left and right side contact portions 11 and 11 (sliding contact portions with the pulley groove surface).
In this case, it is embedded in the hard resin and does not appear on the surface of the block 7 (that is, these portions are made of the hard resin), but other portions may be exposed on the surface of the block 7.

Further, the center pillar 7 on the surface of the block 7 on the belt running direction side (the front side in FIG. 1).
4C, a truncated cone-shaped engagement projection 13 is provided, and as shown in FIG. 4, an engagement hole 14 that engages with the engagement projection 13 is provided on the other surface. And block 7
When is attached to the tension band 1, the engagement of the engagement projections 13 and the engagement holes 14 restricts the displacement of the block in the vertical and horizontal directions, and suppresses the swing of the block. Here, it is desirable that the height of the engagement hole 13 and the depth of the engagement protrusion 14 be as large as possible in order to ensure the above-mentioned engagement even when the pitch between the blocks 7 is large. Therefore, the thickness center of the reinforcing member 12 is the thickness of the entire block 7 (here, the thickness of the entire block 7 refers to the maximum diameter of the thickness of the block 7 excluding the engagement protrusion 13 and the engagement hole 14). The same applies to the following.) The position is located closer to the engagement protrusion 13 than the center. Therefore, the resin thickness on the engagement protrusion 13 side is small, and the resin thickness on the engagement hole 14 side is large. In this manner, the depth of the engagement hole 14 is
And the height of the engagement projections 13 is set to a height that does not interfere with the engagement holes 14 when the pitch between the blocks 7 is small. The lower portion of the top surface of the engagement projection 13 is formed as an inclined surface extending downward and inward from the pitch line in consideration of the bending of the belt.

The lower part (the inside of the belt) of the surface of the block 7 on the side of the engaging projection 13 and the side of the engaging hole 14 is bent to a certain curvature when the belt is wound around the pulley, and the blocks 7 and Since it is necessary to avoid contact between the belts 7, they are formed on an inclined surface directed toward the center of the block thickness toward the inside of the belt. Block 7 of V belt B
Then, as shown in FIG.
Side, the inclination angles on both sides are not equal, the surface on the side of the engagement projection 13 is a small angle (β ₁ ), and the surface on the side of the engagement hole 14 is a large angle (β ₂ ).

Further, as shown in FIG. 3A, the tops of the upper and lower projections 9 and 10 of the block 7 are connected to the lower projection 1.
The configuration is such that both ends of the block 7 in the thickness direction at 0 from the lower end of the block 7 are substantially the same, and are shifted toward the engagement protrusion 13 by δ from the center of the thickness of the entire block 7.

As a feature of the present invention, the V belt B
Is formed by a block 7 having a single shape, variations in the engagement gap, the interference, and the allowance of the block 7 are minimized, the dimensional accuracy is improved, and the pulley on the block 7 is improved. Surface pressure is made uniform, and the durability durability of the belt becomes excellent.

Further, since the block 7 is locked and fixed to the tension band at a plurality of kinds of pitches (for example, 3.0 mm and 3.3 mm), the different pitches are set at a certain ratio (for example, 60 mm).
(If the belt is 0 mm in length, 101 blocks of 3.0 mm pitch and 90 blocks of 3.3 mm pitch)
By randomly attaching to the tension bands 1 and 1 (the 3.0 mm pitch and the 3.3 mm pitch are stochastically arranged at random), a plurality of block pitch sounds are generated when the belt runs. , And the V-belt B has low noise.

Here, the ratio of the difference between the maximum pitch and the minimum pitch to the minimum pitch among the plurality of types of pitches is 5 to 5.
Since it is set to 20%, noise reduction during running of the belt can be properly performed.

Further, since the engaging projections 13 provided on each block 7 are engaged with the engaging holes 14 of the adjacent blocks 7, the displacement of the blocks 7 in the vertical and horizontal directions is restricted. Will smoothly enter the pulley, and vibration and wear will be suppressed.

The center of the thickness of the reinforcing member 12 embedded in the block 7 is located closer to the engaging protrusion 13 than the center of the thickness of the entire block 7, so that the engaging hole provided in the block 7 is provided. The restriction on the depth of the projection 14 is relaxed and provided deep, and the height of the engagement projection 13 is accordingly increased. Therefore, the engagement of the engagement projections 13 with the engagement holes 14 is effective even in a portion where the pitch between the blocks 7, 7 is large.

Here, a plurality of types of mounting pitches of the block 7 to the tension band 1 will be considered, and engagement between the blocks 7 at small pitch and large pitch will be considered. As shown in FIG. 4, the height t of the engagement projection 13, the total thickness T of the block 7, the block mounting pitch p ₁ (small pitch), p ₂
Kakarigodai d _1, d ₂ to the engaging hole 14 of when the (large pitch) engaging projections 13, d ₁ = t flush against _{p 1 (T-p 1)} d with respect to p _{2 2} = T− (T−p ₁ ) − (p ₂ −p ₁ ), and when d ₁ , d ₂ > 0, the engagement protrusion 13 is engaged with the engagement hole 14.
, Which is a condition for restricting the displacement of the block 7 in the vertical and horizontal directions.

Since the engaging projection 13 is formed in a truncated conical shape having a large diameter, the shear strength is increased, and the engaging hole 14 with which the engaging projection is engaged is formed in the reinforcing member 12 to reduce the strength. It will be provided without making it do. That is, if the engaging projections 13 are increased to increase the shear strength, it is necessary to make the engaging holes 14 deep, and in some cases, it is necessary to make a hole in the reinforcing member 12. By making the shape of a truncated cone,
The above-described engagement hole 14 with which the engagement protrusion 13 engages can be provided while increasing the shear strength of the engagement protrusion 13.

As shown in FIG. 4, the portion of the block 7 on the inner peripheral side of the engagement projections 13 or the engagement holes 14 on both sides of the block 7 is directed toward the center of the thickness of the block 7 toward the inside of the belt. Since the inclined surface on the side of the engaging hole 14 has a larger inclination angle than the inclined surface on the side of the engaging projection 13, the blocks 7, 7 adjacent to each other are formed. Contact will be avoided. The inclined surfaces on both sides of the block are necessary to avoid contact between the blocks 7, 7 when the V belt B is wound around the pulley, but the reinforcing member 12 embedded in the block 7 has a thickness center of the block 7. Since it is located closer to the engagement protrusion 13 side, the inclination angle of the inclined surface that can be provided on the engagement protrusion 13 side must be small. However, by providing the inclined surface on the side of the engaging hole 14 larger than that on the side of the engaging projection 13, the shortage of the inclined surface on the side of the engaging projection 13 is compensated for by the inclination angle of the inclined surface on the side of the engaging hole 14. Will be done.

As shown in FIG. 3A, the center of the thickness of the block 7 of the upper and lower projections 9 and 10 of the block 7 is the lower end of the block 7 at both ends in the thickness direction of the block 7 of the lower projection 10. Is shifted by δ from the center of the thickness of the entire block 7 so that the height from the block 7 is substantially the same.
It is assumed that no imbalance occurs in the fitting state of the V belt and the tension belt 1 or the bent state of the V-belt B. That is, if the inclination angles of the inclined surface on the side of the engagement projection 13 and the inclined surface on the side of the engagement hole 14 are different, the top positions of the upper and lower convex portions 9 and 10 coincide with the thickness center of the entire block. In this case, as shown in FIG.
There is a difference in the height of both ends of the block 7 in the thickness direction from the lower end of the block 7 and an imbalance occurs in the fitting state with the tension band 1 or the bending state of the V-belt B. Unbalance will not occur.

In order to increase the block strength and obtain a belt that can withstand high torque, it is desirable that the thickness of the reinforcing member be as large as possible. The high load transmission V-belt B satisfies all of the high dimensional accuracy, durability and low noise by means of mounting the block of a single shape to the tension band at plural pitches while ensuring the displacement in the direction. It is something to do. (Embodiment 2) FIG. 5 shows a vertical section of a high load transmission V-belt C according to Embodiment 2 of the present invention. The same parts as those in the first embodiment are denoted by the same reference numerals. In the V-belt C, the engagement protrusion 13 and the engagement hole 14 have a hemispherical shape. And, in the part where the assembly pitch of the block is large,
The gap c generated between the engagement protrusion 13 and the engagement hole 14 is larger than the gap b (see FIG. 4) in the V-belt B according to the first embodiment. Therefore, the V belt B according to the first embodiment is superior from the viewpoint of restricting the vertical and horizontal displacement of the block.

Other configurations, functions and effects are the same as those of the first embodiment.
Is the same as

[0045]

Next, a specific embodiment will be described. <Preparation of Evaluation Belt> For test evaluation, a high load transmission V-belt having the following components was prepared. Table 1 also shows the configuration of each belt. -Example 1-The belt length is 612 mm, the width of the block at the belt line is 25 mm, the belt angle is 26 °, and the inclination angle of the inclined surface below the block is 3.2 on both the engaging protrusion side and the engaging hole side.
°, the thickness of the block is 2.9 mm, the pitch of the block in the belt length direction is a constant pitch of 3.0 mm, the number of blocks is 204, the height of the engagement protrusion is 0.35 mm, and the depth of the engagement hole is Is 0.40 mm, the engagement allowance between the engagement protrusion and the engagement hole is 0.25 mm, and the tops of the upper and lower protrusions are located at the center of the thickness of the block.
Example of a high-load transmission V-belt in which a reinforcing member made of a lightweight, high-strength aluminum alloy of ± 0.5 mm is insert-molded in phenolic resin so that the center of thickness matches the center of thickness of the block. It was set to 1.

Example 2 The pitch of the blocks in the belt length direction is 3.0 mm and 3.0 mm.
3 mm, and they are arranged at random. When the pitch is 3.0 mm, the engagement allowance is 0.25 mm, and when the pitch is 3.3 mm, the engagement allowance is −0. .05 mm (the engagement protrusion and the engagement hole were not engaged), and the number of blocks was 195.
A high-load transmission V-belt having the same configuration as that of Example 1 except that the belt was used was used as Example 2. Here, 105 of the 195 blocks had a pitch of 3.0 mm, and 90 had a pitch of 3.3 mm. -Example 3-The inclination angle of the inclined surface below the block is 2.0 on the engagement protrusion side.
°, the engagement hole side was 4.0 °, the pitch of the block in the belt length direction was 3.0 mm and 3.3 mm, and they were randomly arranged. Is 3.00 mm, the engagement allowance is 0.50 mm, and when the pitch is 3.3 mm, the engagement allowance is 0.20 mm.
mm, the height of the engagement protrusion is 0.60 mm, the depth of the engagement hole is 0.65 mm, and the tops of the upper and lower protrusions are 0.15 mm from the thickness center of the block. A high load having the same configuration as that of Example 1 except that the reinforcing member is located on the engaging projection side and the center of thickness of the reinforcing member is located 0.25 mm from the center of thickness of the block. The transmission V-belt was Example 3. Here, 105 out of the 195 blocks had a pitch of 3.0 mm, and 90 blocks had a pitch of 3.3 mm.

[0047]

[Table 1] <Test evaluation method> A durability running test was performed on the belts of each example, and the belt noise was measured both at the initial stage of the running and at the running time after a lapse of a predetermined time. The belt durability running test conditions are as follows. That is, as shown in FIG. 6, a driving pulley 21 having a diameter of 126 mm and a diameter of 70.8 m
m is wound around the driven pulley 22, and a load is applied to the driven pulley 22 so that the axial load becomes 1764 N, and the driving pulley 21 is set to 63.4 N · at an ambient temperature of 100 ° C. m drive torque and 5285 rpm
, And the durability of the belt 23 was evaluated.
At this time, a torque of 113.2 N · m was generated in the driven pulley 22, and the driven pulley 22 was rotated at a rotation speed of 9435 rpm.

On the other hand, the noise test of the belt 23 in each example was performed using the noise level meter after removing the belt 23 from the running test device at each evaluation time. That is, as shown in FIG. 7, the belt 23 of each example is wound around the driving pulley 21 having a diameter of 64 mm and the driven pulley 22 having a diameter of 128 mm, and a load is applied to the driven pulley 22 so that the axial load becomes 1960N. ,
At room temperature, the driven pulley 22 is set to no load,
Is rotated at a rotation speed of 2500 rpm, and the microphone is located at a position 50 mm closer to the driven pulley 22 from the driving pulley 21 and 100 mm away from the driving pulley 21 on a plane passing through the rotation axis of the driving and driven pulleys 21 and 22. Was installed and the noise was measured. <Test Evaluation Results> Table 2 shows the test evaluation results of the V belts according to the respective examples. According to the table, it can be seen that, compared to Example 1, in Examples 2 and 3, the two types of block assembling pitches were arranged at random, thereby reducing noise during belt running. In the result of the frequency spectrum, a peak occurs at a frequency corresponding to an average pitch of 3.05 mm and a pitch of 3.15 mm, but is dispersed by the pitches of 3.0 mm and 3.3 mm. Is a few decibels lower.

The second embodiment uses the same blocks as the first embodiment. The reinforcing member buried to secure the block strength is designed to be thick and the center line of the reinforcing member thickness is made to coincide with the center line of the block thickness. Therefore, the height of the engaging projections (depth of the engaging holes) cannot be increased. When the assembly pitch is 3.3 mm, the engaging projections do not engage with the engaging holes as shown in FIG. As a result, the function of regulating the displacement of the block in the vertical and horizontal directions is not performed. On the other hand, in Example 3, as shown in FIG. 4, the center line of the reinforcing member thickness is shifted by 0.25 mm from the center line of the block thickness. Can be increased, and even if the assembly pitch is set to 3.3 mm, the allowance remains, and the function of regulating the displacement of the block in the vertical and horizontal directions can be properly performed. In view of the above, even in Examples 2 and 3 in which a plurality of types of block mounting pitches were used in the same manner, in Example 2, a resin chip of the block occurred, which caused a problem in durability reliability. In Example 3, since the engagement between the blocks was reliable, it was possible to reduce the noise without affecting the durability reliability.

[0050]

[Table 2]

[Brief description of the drawings]

FIG. 1 is a perspective view of a high-load transmission V-belt according to Embodiment 1 of the present invention.

FIG. 2 is a side view of the high-load transmission V-belt according to the first embodiment of the present invention.

3A is a side view of a block of a high-load transmission V-belt according to Embodiment 1 of the present invention, and FIG. 3B is a side view of a block of a high-load transmission V-belt according to another embodiment of the present invention. It is.

FIG. 4 is a side sectional view of the high-load transmission V-belt according to the first embodiment of the present invention.

FIG. 5 is a side sectional view of a high-load transmission V-belt according to a second embodiment of the present invention.

FIG. 6 is a schematic diagram showing a layout of a belt durability test apparatus.

FIG. 7 is a schematic diagram showing a layout of a belt noise test device.

8A is a sectional view of a conventional high-load transmission V-belt, FIG. 8B is a side view of a tension band, and FIG. 8C is a side view of a block.

FIG. 9 is a side sectional view of a high-load transmission V-belt according to a conventional example.

FIG. 10 is a side cross-sectional view of a conventional high-load transmission V-belt when the block pitch is random.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 tension band 1 a shape-retaining layer 1 b core wire 2 upper concave portion 3 lower concave portion 4 canvas 7 block 7 a upper beam 7 b lower beam 7 c center pillar 8 fitting portion 9 upper convex portion 10 lower convex portion 11 a upper contact portion 11 b lower side Contact portion 12 Reinforcement member 13 Engagement protrusion 14 Engagement hole 21 Drive pulley 22 Follower pulley 23 Belt a Tension band b Minimum gap between the engagement protrusion surface of V-belt B and the surface constituting the engagement hole c V-belt C minimum gap Kakarigodai e upper recess f lower recesses g block h engagement with Kakarigodai d ₂ larger portion of the pitch of a small portion of d ₁ pitch and the surface constituting the engaging projection surface and the engaging hole part i upper protrusions j lower protrusion k projection l engaging projection m engaging holes n reinforcing member p ₁ height smaller pitch p ₂ greater pitch t engagement projection t ₁ meshing clearance t ₂ mesh thickness T block Overall thickness α tension Shift length from the back abutment angle beta ₁ engaging protrusion-side inclined angle beta ₂ engaging hole side inclination angle δ vertical engagement portion block thickness thickness center of the entire block of the center of the inclined surface of the inclined surface of the band

Claims (5)

[Claims] An endless tension band, a plurality of contact portions which are fixed to a plurality of pitches along the belt length direction and are provided in contact with the pulley groove on a side surface in a belt width direction. A high-load transmission V-belt comprising: a block having the same shape as described above, wherein each of the blocks includes an engagement protrusion provided on one surface in a belt length direction and an engagement hole provided on the other surface. With
The engagement protrusion of one block of the pair of adjacent blocks is engaged with the engagement hole of the other block, and the center of thickness is located closer to the engagement protrusion than the center of thickness of the entire block. A high-load transmission V-belt comprising a reinforcing member embedded as described above. 2. The V-belt for high-load transmission according to claim 1, wherein the engagement protrusion has a truncated cone shape or a hemispherical truncation shape. 3. The high-load transmission V-belt according to claim 1, wherein a portion of the engagement protrusion or the engagement hole on both surfaces of the block on the inner peripheral side of the belt is blocked inward of the belt. A high load transmission V formed on an inclined surface inclined toward the center of the thickness, wherein the inclined surface on the side of the engaging hole has a larger inclination angle than the inclined surface on the side of the engaging projection. belt. 4. The high-load transmission V-belt according to claim 3, wherein the block has a fitting portion into which the tension band is press-fitted and fitted, and an upper meshing portion is provided on an upper surface of the fitting portion. However, a lower meshing portion is formed on the lower surface, the lower meshing portion facing the upper meshing portion and having a symmetrical cross section in the thickness direction of the block, and a top portion of the upper and lower meshing portions of the block is a lower meshing portion. A high-load transmission V-belt, which is provided so as to be shifted from the thickness center of the entire block so that the height of both ends in the block thickness direction from the lower end of the block is substantially the same. 5. The high-load transmission V-belt according to claim 1, wherein a ratio of a difference between a maximum pitch and a minimum pitch to the minimum pitch among a plurality of types of pitches is 5 to 5. A high-load transmission V-belt characterized by being 20%.