JPH0914356A - V belt for high load transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid shortening of longevity of a belt caused by an offsetting property by extensively minimizing the one-sided property of a V belt due to inclination of a core wire of each tension belt in the belt traveling direction at the time of engaging and fixing a large number of blocks on an air of the left and right endless tension belts provided in the belt cross direction in parallel wit a specified pitch interval in the belt longitudinal direction on the V belt for high load transmission. SOLUTION: A core wire 3 of a left side tension belt 1 is spiral wound so as to be inclined leftward relative to a belt traveling direction R, while a core wire 3 of a right side tension belt 1 is spirally wound so as to be inclined rightward relative to the belt traveling direction R.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high load transmission V-belt used in a belt transmission such as a belt type continuously variable transmission in an automobile or a general-purpose machine for agriculture.
In particular, the present invention relates to a technique for reducing deviation in the belt width direction when traveling while being wound around a pulley.

[0002]

2. Description of the Related Art For example, a gear type or a fluid type is widely used as a transmission for agricultural machines such as combine and tractor and automobiles, but in recent years,
Belt-type continuously variable transmissions are being developed with the aim of improving the operability during shifting and the fuel consumption rate. The belt of such a transmission is required to have an extremely high torque transmission capability. Therefore, a general rubber V-belt cannot endure the high lateral pressure in the pulley groove and causes buckling deformation. Therefore, it cannot be put to practical use.

Therefore, conventionally, for example, Japanese Patent Laid-Open No. 60-4
The V-belt for high load transmission described in JP-A-9151, JP-A-61-103029 and JP-A-62-146033 is used.
As shown schematically in FIG. 7, each of these has a core wire a.
A pair of left and right endless tension bands b, which are embedded in a rubber-like elastic body in a spirally wound state, are made of a hard material having a large friction coefficient and excellent wear resistance. The blocks c, c, ... Are locked and fixed at a predetermined pitch in the belt length direction, and the left and right side surfaces of each block c are slidable contact portions d with the pulley groove. It can withstand high lateral pressure and can sufficiently transmit high load torque.

[0004]

By the way, in the tension band b used in the V-belt, the core wire a is inclined spirally by a predetermined angle θ with respect to the belt running direction R. There is. Therefore, when belt tension is applied to each tension band b while the V-belt is wound around the pulley and travels, the tension band b is pulled in the inclination direction of the core wire a, and therefore the belt width with respect to the belt. A biasing force F in the direction is generated, and one sliding contact portion d of each block c
Excessive surface pressure is applied only to the left sliding contact portion d in the example shown in FIG. 7. As a result, the abrasion of the sliding contact portion d becomes large, and the trouble that the life of the belt is shortened due to damage of the block c, heat generation, or the like easily occurs.

In order to solve the above problems, it is conceivable to change the twisting direction between the lower twist and the upper twist when manufacturing a core wire, for example. However,
Although such measures may be able to suppress the deviation a little, it is difficult in principle to eliminate it completely. On the contrary, since the twisting direction is restricted, the flexibility of designing the core wire is narrowed.

The present invention has been made in view of the above points, and its main object is to provide a high load transmission V-belt used in a belt transmission such as a belt type continuously variable transmission with a tension band. Paying attention to the fact that it is used on both the left and right sides of the belt, and by devising the combination of both tension bands, the deviation of the V-belt is greatly reduced, and the belt life due to such deviation is shortened. It is to be able to avoid shortening the life.

[0007]

In order to achieve the above-mentioned object, in the invention of claim 1, two kinds of tension bands, in which the spirally wound core wires are wound in opposite directions to each other, are combined. By using this, the biasing forces between both tension bands are canceled by each other.

Specifically, according to the present invention, a large number of blocks are locked and fixed to a pair of left and right endless tension bands arranged side by side in the belt width direction with a predetermined pitch in the belt length direction. It is a prerequisite for the high load transmission V-belt.

Each of the tension bands is an elastic body, and a core wire embedded in the elastic body and spirally wound so as to be aligned in the belt width direction in a state of being inclined at a predetermined angle with respect to the belt running direction. And. Further, it is assumed that the cores of both tension bands are spirally wound so as to incline in opposite directions with respect to the belt running direction.

With the above structure, the high load transmission V-belt is wound around the pulleys to be driven and run, and each tension band is
A tension for pulling the tension band toward the belt running direction and a tension for pulling toward the direction inclined by a predetermined angle with respect to the belt running direction of the cord are added,
As a result, as a resultant force of both tensions, when a biasing force in the belt width direction is generated in each tension band, the core lines of the left and right tension bands are inclined to be opposite to each other in the belt running direction. Since it is wound in a spiral shape, the directions of the offset forces between the tension bands are also opposite to each other. Therefore, in the high load transmission V-belt, the biasing forces due to the tension bands cancel each other out.

According to a second aspect of the present invention, in the above first aspect of the invention, the core wire of the left tension band is inclined leftward with respect to the belt running direction, and the core wire of the right tension band is inclined rightward. It shall be wound.

With the above structure, the offset force of the left tension band is generated leftward in the belt running direction, while the offset force of the right tension band is generated rightward. The action is carried out concretely.

According to a third aspect of the present invention, in the above-mentioned first aspect of the invention, the left tension band has a core extending rightward with respect to the belt running direction, and the right tension band has a core extending in a leftward spiral. It shall be wound.

With the above construction, contrary to the second aspect, the biasing force of the left tension band is generated rightward in the belt running direction, while the biasing force of the right tension band is generated leftward. . Therefore, also in the present invention, the action in the invention of claim 1 is specifically carried out.

According to the invention of claim 4, based on the same premise as that of the invention of claim 1, each tension band is an elastic body and is embedded in the elastic body and is inclined by a predetermined angle with respect to the belt running direction. And a core wire wound in a spiral shape so as to be aligned in the belt width direction, while each block is provided on both left and right side surfaces of the block, and a sliding contact portion capable of sliding contact with the groove surface of the pulley, The block has slit-shaped fitting portions which are provided on both left and right sides of the block so as to extend in the belt width direction and which fit the tension bands. On the upper and lower surfaces of the tension band, upper and lower corresponding locking portions are provided with a predetermined pitch interval in the belt length direction, and on the upper and lower edges of the fitting portion of each block, respectively. An engaging portion that engages with the locking portion of the tension band is provided, and each block is locked and fixed to the tension band by the engagement of the locking portion of the tension band and the engaging portion of each block. I shall. Further, it is assumed that the cores of both tension bands are spirally wound so as to incline in opposite directions with respect to the belt running direction. Therefore, the same operation as in the case of the first aspect of the invention is performed.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 2 shows the overall construction of a high load transmission V-belt according to Embodiment 1 of the present invention. Although not shown, the high load transmission V-belt constitutes a belt-type continuously variable transmission that is wound around two drive-side and follow-side shift pulleys, each of which includes a fixed sheave and a movable sheave. It is used at the time, and a large number of blocks 8, 8, ... Are attached to a pair of left and right endless tension bands 1, 1.
Are locked and fixed at a predetermined pitch in the belt length direction.

Each of the tension bands 1 has the same cross-sectional shape and size, and the shape-retaining layer 2 made of a rubber-like elastic material.
And is buried in the upper and lower central portions of the shape-retaining layer 2,
As shown in FIG. 3, the core wires 3, 3, ... Are spirally wound so as to be arranged at a predetermined pitch in the belt width direction in a state of being inclined at a predetermined angle θ with respect to the belt traveling direction R. That is, the number of buried cores 3 (the number of windings of the cores 3) between the tension bands 1 and 1 is equal to each other. Further, the upper surface of the shape-retaining layer 2 is covered with an upper canvas 4 and the lower surface thereof is covered with a lower canvas 5.

On the upper surface of each of the tension bands 1, a large number of upper surface grooves 6 extending in the belt width direction and having a concave cross section are formed.
, ..., and the lower surface has the upper surface grooves 6, 6 ,.
A plurality of lower surface grooves 7, 7 ... Which extend vertically in the belt width direction and have an arcuate cross section are provided at predetermined pitch intervals in the belt length direction. The upper surface groove 6 and the lower surface groove 7 constitute the locking portion of the present invention.

On the other hand, each of the blocks 8 has a substantially inverted trapezoidal plate shape, and the left and right side surfaces thereof are slidable contact portions 9, 9 which slidably contact the groove surfaces of the speed change pulley. Also, each block 8
Slit-shaped fitting portions 10 that penetrate the belt in the length direction and are open to the side are provided on both left and right sides of the belt so as to extend in the belt width direction. This fitting part 1
The upper edge portion of 0 has a reverse convex shape in cross section that protrudes downward, and is a downward protrusion 11 that engages with the upper surface groove 6 of the tension band 1. On the other hand, the lower edge of the fitting portion 10 has an arcuate cross-section that bulges upward, and serves as an upward protrusion 12 that engages with the lower surface groove 7 of the tension band 1. The engaging portions of the present invention are constituted by these ridges 11 and 12.

As a characteristic of the present invention, as schematically shown in FIG. 1, the core wires 3 of the tension bands 1 and 1 are spirally formed so as to be inclined in directions opposite to each other with respect to the belt running direction R. It is rolled.

Specifically, the core wire 3 of the left tension band 1 is
Is spirally wound so as to be inclined leftward with respect to the belt traveling direction R, while the core wire 3 of the right tension band 1 is
It is spirally wound so as to be inclined rightward with respect to the belt traveling direction R. This is the core wire 3 at the time of manufacturing the tension band.
Expressed in the winding direction viewed from the winding end end side, the core wire 3 of the left tension band 1 is left-handed (counterclockwise wound state).
On the other hand, the core wire 3 of the right tension band 1 is right-handed (clockwise wound).

Next, the biasing force applied to the V-belt for high load transmission when the V-belt for high-load transmission is wound around both speed change pulleys and travels will be described.

When the high load transmission V-belt is driven to run, tensions are applied to the tension bands 1 to pull the tension bands 1 in the belt running direction R. Then
Each tension band 1 is also applied with tension to pull it in the direction of inclination of the core wire 3. As a result, a biasing force F in the belt width direction is generated in each tension band 1 as a resultant force of both tensions.

At this time, between the tension bands 1 and 1 on both the left and right sides, since the respective cords 3 are inclined in the directions opposite to each other with respect to the belt running direction R, the direction of the offset force F in each tension band 1 is also. The directions are opposite to each other. That is, the offset force F of the left tension band 1 is generated leftward, while it is generated rightward in the right tension band 1. Therefore, as a V belt for high load transmission,
When both tension bands 1 and 1 are separated from each other, each biasing force F
Will be canceled each other.

Therefore, according to this embodiment, since the deviation of the high load transmission V-belt can be made substantially zero, the shortening of the belt life due to such deviation can be avoided. it can.

In the first embodiment described above, the V-belt for high load transmission used in the belt type continuously variable transmission has been described. However, it may be a belt transmission configured to transmit a rotational force between a plurality of pulleys. It can be applied to the belt.

(Embodiment 2) FIG. 3 schematically shows a V-belt for high load transmission according to Embodiment 2 of the present invention, and the same parts as those in Embodiment 1 are designated by the same reference numerals. The explanation is omitted.

Further, as a feature of the present invention, the core wire 3 of the left tension band 1 is spirally wound so as to be inclined rightward with respect to the belt traveling direction R, contrary to the case of the first embodiment. On the other hand, the core wire of the right tension band is spirally wound so as to be inclined leftward with respect to the belt traveling direction R.

In other words, the core wire 3 of the left tension band 1 is right-handed (when it is wound clockwise when viewed from the winding end side), while the core wire 3 of the right tension band 1 is left-handed (winding). It is a state in which it is wound counterclockwise as seen from the end end side).

Therefore, according to this embodiment, in the tension band 1 on the left side, the offset force F is generated in the right direction, while
In the tension band 1 on the right side, a biasing force F is generated leftward. Therefore, in this case, the biasing forces F of the tension bands 1 and 1 can be canceled with each other in a state where the tension bands 1 and 1 are close to each other, and this embodiment can also achieve the same effect as that of the first embodiment. it can.

In the first and second embodiments, each block 8 has the fitting portions 10, 10, ... Opened to the side on both left and right sides. As the block of the transmission V-belt, various types can be used. Here, as an example,
The first to third modifications will be described with reference to the drawings.

-Modification 1- FIG. 4 shows a high load transmission V-belt according to Modification 1,
Here, each block 18 is composed of an upper block 12 forming an upper beam extending in the belt width direction, and a lower block 13 including a lower beam 13a arranged in parallel with the upper beam. The lower block 13 is erected at the center of the lower beam 13a, and the upper ends of the center pillars 13b are integrally connected to the lower surface of the central portion of the upper block 12, and are erected at the left and right ends of the lower beam 13a, respectively. Left and right pillars 13c and 13d whose upper ends are integrally connected to the lower surfaces of the left and right ends of the upper block 12 are provided.

The upper block 12 and the lower beam 13a of the lower block 13 are provided on the left and right sides of the blocks 18, respectively.
And a pair of fitting portions 20 and 20 formed of rectangular through holes formed by the pillars 13b to 13d, respectively, and the tension bands 1 are inserted into the fitting portions 20 and 20, respectively. Since the other configurations are the same as those of the first embodiment, the same parts are designated by the same reference numerals and illustrated, and the description thereof is omitted.

-Modification 2- FIG. 5 shows a V-belt for high load transmission according to Modification 2,
In this modification, each block 28 has a shape similar to that of the lower block 13 of Modification 2 described above. That is, each block 28 has a lower beam 28a extending in the belt width direction.
And a center pillar 28b standing upright at the center of the lower beam 28a, and left and right pillars 28c and 28d standing upright at both left and right ends of the lower beam 28a. Further, insertion holes 21, 21, ... Having a circular cross section that penetrate in the belt width direction are provided at the upper ends of the pillars 28b to 28d. An upper beam 22 having a circular cross section is inserted into and held in these insertion holes 21, 21 ,.

The upper beam 22 and the lower beam 2 of the block 28 are provided on both left and right sides of each block 28.
8a and the pillars 28b to 28d are formed with a pair of fitting portions 30 and 30 formed of rectangular through holes, and the tension bands 1 are inserted into the fitting portions 30 and 30, respectively. . Since the other configurations are the same as those of the first embodiment, the same parts are designated by the same reference numerals and illustrated, and the description thereof is omitted.

-Modification 3- FIG. 6 shows a high load transmission V-belt according to Modification 3,
Here, each block 38 includes an upper block 31 and a lower block 32 that extend in the belt width direction. The blocks 31 and 32 are vertically connected by two coupling pins 33 and 33 arranged in the belt width direction.

Between the upper and lower blocks 31 and 32, there are formed slit-like fitting portions 40 which are open to the left and right sides. Then, one tension band 1 is inserted into the fitting portion 40 in a state of being joined to each other in the belt width direction.

On the upper surface of the tension band 1, there are upwardly protruding ridges 6 ', 6', ... Which extend in the belt width direction and project upward, and on the lower surface thereof, the upward ridges. Downward projecting strips 7 ', 7', ... having a reverse convex cross section that extend in the belt width direction corresponding to the upper and lower sides of the projecting strips 6 ', 6', and project downward are respectively provided in the belt length direction. It is provided at a predetermined pitch interval.

On the other hand, the upper edge of the fitting portion 40, that is, the lower side of the upper block 31, is provided with an upper groove 11 'extending in the belt width direction and having an inverted concave cross section. Lower blocks 12 'extending in the belt width direction and having a concave cross section are provided on the upper side of the block 32, respectively. Since the other configurations are the same as those of the first embodiment, the same parts are designated by the same reference numerals and illustrated, and the description thereof is omitted.

In the high load transmission V-belt of the type of this modified example, conventionally, each block 38 is hooked and fixed to one tension band. In other words, in this modified example, the above-mentioned one tension band is divided into a pair of left and right tension bands 1,1 and, between these tension bands 1,1, each core wire 3 extends in the belt running direction. On the other hand, it is supposed to be wound in a spiral shape so that they are inclined in opposite directions, and with these things,
Even in a high-load transmission V-belt of the type having one tension band, it is possible to avoid shortening the belt life due to the deviation of the tension band.

[0041]

As described above, according to the inventions of claims 1 and 4, in the high load transmission V-belt, there are a pair of left and right endless tension bands arranged in parallel in the belt width direction,
When locking and fixing a number of blocks in the belt length direction at a predetermined pitch, the cores of the tension bands are spirally wound so as to incline in opposite directions with respect to the belt running direction. Since the biasing forces of the tension bands can be canceled by each other, the biasing property due to the cores of the tension bands tilting spirally with respect to the belt running direction can be significantly reduced. It is possible to avoid shortening the life of the belt due to such deviation.

According to the second aspect of the invention, the core wire of the left tension band is spirally wound so as to be tilted leftward with respect to the belt running direction, while the core wire of the right tension band is tilted rightward.
Further, in the invention of claim 3, the core wire of the left tension band is inclined to the right, while the core wire of the right tension band is inclined to the left. Therefore, according to any one of the inventions of claim 2 and 3, The effect of the invention of claim 1 can be specifically obtained.

[Brief description of the drawings]

FIG. 1 is a plan view schematically showing a part of a high load transmission V-belt according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a part of a high load transmission V-belt.

FIG. 3 is a view equivalent to FIG. 1 and schematically showing a part of a high load transmission V-belt according to a second embodiment of the present invention.

FIG. 4 is a view corresponding to FIG. 2, showing a modified example 1 of the V-belt for high load transmission.

FIG. 5 is a view, corresponding to FIG. 2, showing a modified example 2 of the V-belt for high load transmission.

FIG. 6 is a view corresponding to FIG. 2 showing a modified example 3 of the V-belt for high load transmission.

FIG. 7 is a view corresponding to FIG. 1 schematically showing a conventional high load transmission V-belt.

[Explanation of symbols]

 1 Tension band 3 Core wire 6 Upper surface groove (locking part) 7 Lower surface groove (locking part) 8, 18, 28, 38 Block 11 Downward projecting ridge (engaging part) 12 Upward projecting ridge (engaging part) R Belt Traveling direction

Claims (4)

[Claims] 1. A V-belt for high load transmission in which a large number of blocks are locked and fixed to a pair of left and right endless tension bands arranged side by side in the belt width direction at predetermined pitch intervals in the belt length direction. The tension bands include an elastic body, and a core wire that is embedded in the elastic body and is spirally wound so as to be aligned in the belt width direction with a predetermined angle with respect to the belt traveling direction. A V-belt for high-load transmission, characterized in that the cores of both tension bands are spirally wound so as to incline in opposite directions to the belt running direction. 2. The V-belt for high load transmission according to claim 1, wherein the core wire of the left tension band is spirally wound so as to incline leftward with respect to the belt running direction, while the core wire of the right tension band. The V-belt for high load transmission is characterized in that the line is spirally wound so as to be inclined rightward with respect to the belt traveling direction. 3. The V-belt for high-load transmission according to claim 1, wherein the core wire of the left tension band is spirally wound so as to be inclined rightward with respect to the belt running direction, while the core wire of the right tension band. The V-belt for high load transmission is characterized in that the line is spirally wound so as to be inclined leftward with respect to the belt traveling direction. 4. A high-load transmission V-belt in which a large number of blocks are locked and fixed to a pair of left and right endless tension bands arranged side by side in the belt width direction at predetermined pitch intervals in the belt length direction. The tension bands include an elastic body, and a core wire that is embedded in the elastic body and is spirally wound so as to be aligned in the belt width direction with a predetermined angle with respect to the belt traveling direction. Each of the blocks is provided on both left and right side surfaces of the block and slidably contactable with the groove surface of the pulley, and on both left and right sides of the block so as to extend in the belt width direction. The tension band has slit-shaped fitting portions, and the upper and lower surfaces of the tension band are respectively provided with engaging portions corresponding to the upper and lower sides at predetermined pitch intervals in the belt length direction. , The upper and lower edges of the fitting part of each block above Each of the blocks is provided with an engaging portion that engages with the locking portion of the tension band, and each block is locked and fixed to the tension band by the engagement of the locking portion of the tension band and the engaging portion of each block. A V-belt for high-load transmission, characterized in that the cores of both tension bands are spirally wound so as to incline in mutually opposite directions with respect to the belt running direction.