JPH0142681Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a V-belt used in a dry transmission.

(Prior Art) Currently, gear type transmissions and hydraulic type transmissions are used as transmissions for driving automobiles. As a transmission device that combines these advantages, a belt-type continuously variable transmission device with excellent operability and good fuel efficiency is being developed.

This belt-type continuously variable transmission is constructed by attaching variable speed pulleys with variable pulley groove spacing to the drive shaft and driven shaft, and wrapping a V-belt between the two variable speed pulleys to adjust the pulley groove spacing. It changes the rotation pitch diameter and provides stepless speed change.

There are two types of belt-type continuously variable transmissions: one is a wet type transmission that uses a metal V-belt (see, for example, Japanese Patent Publication No. 1983-6783), and the other uses a rubber V-belt. This is a dry type transmission device (see, for example, Japanese Utility Model Publication No. 10408/1983).

In general, variable speed pulleys are made of metal materials such as cast iron, steel, and aluminum alloys, so metal V
Belts must be used in lubricating oil to prevent seizure and wear on friction surfaces, but rubber V-belts do not require this and are advantageous in terms of cost reduction and maintenance.

Incidentally, a transmission for driving an automobile is required to have an extremely high torque transmission capability. For example, when transmitting the maximum torque of a 1000 c.c. engine using a rubber V-belt, the V-belt must withstand side pressure of around 20 kg/cm ² .

However, the standard rubber V-belts currently in practical use are usually used at 4 to 5 kg/cm ² or less, and even high-load rubber V-belts have a load of 10 kg/cm 2 or less.
The limit is around ^cm2 . This is because the rubber V-belt undergoes buckling deformation under high lateral pressure and is destroyed with the generation of heat in the V-belt.

Therefore, the inventor developed a V-belt (see Japanese Patent Application No. 139895/1982), which is constructed by locking a plurality of blocks to an endless tension band.

(Problem to be solved by the invention) However, since materials with a high coefficient of friction are generally used for blocks for high-load transmission,
A problem arose in that the tension band was worn at the contact surface between the block and the tension band, and cracks were generated from this worn portion, leading to early breakage of the tension band.

The present invention has been developed in view of these points, and is a V-belt for high-load transmission that eliminates the problems of the rubber V-belts and metal V-belts, and in particular suppresses the wear of the elastic tension bands and prevents their early breakage. The purpose is to provide the following.

(Means for Solving the Problems) In order to achieve the above object, the present invention has a pair of endless elastic tension bands having a core body, and an engagement groove formed of a non-metallic material and opening on both sides. an engaging recess is formed on the lower surface of the elastic tension band, an engaging protrusion is formed on the lower surface of the engagement groove of the block, and the elastic tension band is formed in the engagement groove of the block. By being engaged with the elastic tension band, the engagement concave portion of the elastic tension band and the engagement convex portion of the block are engaged, and the block is locked to the elastic tension band so that it can be attached and detached only in the belt width direction. teeth,
The block body is characterized in that a lubricating resin layer is provided on at least the inner surface of the engagement groove that contacts the elastic tension band.

(Function) At least the lubricating resin layer on the inner surface of the engagement groove of the block body that contacts the elastic tension band prevents the elastic tension band from being worn out.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

As shown in FIGS. 1 and 2, V-belt 1
comprises a pair of elastic tension bands 2, 3 and a plurality of blocks 4 arranged in the elastic tension bands 2, 3 in the longitudinal direction thereof.

The side surfaces 4a, 4b of the block 4 are inclined to form an angle .alpha. which substantially matches the pulley groove angle of the speed change pulley. The upper surface 4c and lower surface 4d of the block 4 are respectively formed into a convex shape such as an arch shape and a concave shape for the purpose of reducing the weight of the V-belt. Lower opposing surface 4 between blocks 4 and 4
e, 4f, one surface 4f is inclined and the other surface 4e
is approximately vertical and forms an angle β that matches the minimum pitch diameter of the speed change pulley.

Also, as shown in detail in Figure 3, block 4
Engagement grooves 5 that open to the side surfaces 4a and 4b are provided on the sides of the
6 are formed respectively, and the upper surfaces 5a, 6 of each engagement groove are formed.
a and the lower surfaces 5b and 6b have engaging protrusions (upper surface 6a
and engagement protrusions 6c formed on the lower surfaces 5b and 6b.
and 5d and 6d only) are provided respectively.

Further, the block 4 has a lubricating resin layer 4 on the block body 4A, as shown in detail in FIGS. 6a and 6b.
B is integrally and inseparably coated. Therefore,
Even if the lubricating resin layer 4B is worn out, the block body 4A
Less peeling. This lubricating resin layer 4B is formed on the inner surfaces of the engagement grooves 5 and 6 (the upper and lower surfaces 5a, 6a, 5
b, 6b and side surfaces 5e, 6e), which alone is sufficient as a wear countermeasure for the elastic tension bands 2, 3, but as shown in FIG.
The contact surface with the speed change pulley (i.e. the side surfaces 4a, 4
Of course, all surfaces except b) may be coated with the lubricating resin layer 4D.

The material constituting the block main body 4A of the block 4 is a hard resin with a high coefficient of friction in order to contact the speed change pulley, withstand side pressure, and perform frictional transmission. On the other hand, for the lubricating resin layers 4B and 4D, resins such as polyacetal, nylon, and Teflon, which have self-lubricating properties, may be used as they are, or graphite may be used even if the resin does not have self-lubricating properties. , carbon fiber, solid lubricant such as molygden disulfide, or liquid lubricant may be added to impart lubricity.

In addition, in order to improve the adhesion between the lubricant resin layers 4B, 4D and the block body 4A, the resin A and the lubricant resin B constituting the block body 4A are made of the same base resin, and the resin A is an aromatic resin. The lubricating resin B is preferably obtained by blending a lubricant, and both A and B are molded using a two-color injection molding method, while the resin is reinforced with short polyamide fibers, glass fibers, etc. to obtain a high coefficient of friction. Further, it is preferable that the adhesive interface has an uneven shape.

The elastic tension bands 2, 3 each have a non-extensible core body 7, 7 arranged substantially in the same plane;
It is composed of rubber members 8, 9 that hold the core bodies 7, 7, and woven fabrics 10, 10 and 11, 11 embedded near the upper and lower surfaces.

One side surface 2a, 3a of the elastic tension bands 2, 3
has an inclination of substantially the same slope as the sides 4a, 4b of the block 4, but the other sides 2b, 3b need not have such an inclination. Further, as shown in FIG. 4, the upper and lower surfaces of the elastic tension bands 2 and 3 are provided with engagement recesses (elastic tension bands 3 (only engagement recesses 3c and 3d are shown) are provided.

Note that the engagement convex portion of the block 4 and the elastic tension band 2,
The engagement recess 3 connects the block 4 and the elastic tension bands 2 and 3.
It is a means of exchanging power with.

The non-extensible core bodies 7, 7 constituting the elastic tension bands 2, 3 are made of synthetic fibers such as polyamide, polyester, and polyaramid, inorganic fibers such as steel, glass, and carbon, or monofilament or blends thereof. Used as a multifilament cord or textile. It may also be used as a film or sheet.

On the other hand, the rubber members 8 and 9 are required to be made of a material with a large compressive Young's modulus and excellent wear resistance, and generally known synthetic rubber reinforced with short fibers is used.

The woven fabrics 10 and 11 are required to be made of materials with excellent flexibility and abrasion resistance, and are generally made of textile fibers such as cotton, polyamide, polyester, and polyaramid, or blends thereof. Also, a synthetic resin sheet may be used instead of woven fabric. In addition,
In the case of relatively light loads, the woven fabric and synthetic resin sheet may be omitted.

The side surfaces 2a, 3a of the elastic tension bands 2, 3 and the side surfaces 4a, 4b of the block 4 are arranged so that they are substantially on the same plane when engaged with the grooves of the speed change pulley (state of power transmission). It has been adjusted.

With the above construction, as shown in FIG.
The side surfaces 2a and 3a of the block 4 are respectively the side surfaces 2a and 3a of the block 4.
It protrudes slightly from a and 4b. This is because the compressive Young's modulus of the elastic tension bands 2 and 3 is generally determined by the rubber members 8 and 9 reinforced with short fibers, and is smaller than the compressive Young's modulus of the block 4.

FIG. 5 shows the power transmission state when the V-belt 1 engages with the speed change pulley 21 and receives side pressure.
Side surfaces 4a, 4b of block 4 and elastic tension bands 2, 3
The side surfaces 2a and 3a of are substantially on the same plane, and the friction transmission force with the speed change pulley 21 is generated on all the side surfaces. In this case, since the block 4 block main body 4A has a large compressive Young's modulus, buckling deformation does not occur, and the V-belt 1 can withstand high side pressure and has a large frictional transmission force (transmission capacity). In addition, elastic tension band 2,
The contact surface of block 3 with block 4 is a lubricating resin layer 4B.
The amount of wear is reduced due to the lubricating action of the elastic tension bands 2, 3, and no cracks or breaks occur in the elastic tension bands 2, 3.

When the V-belt 1 transitions from a separated state to an engaged state with the speed change pulley 15, the elastic tension bands 2 and 3 engage with the speed change pulley 21 and receive a compression action, and then the block 4 engages with the speed change pulley 21. match. that time,
The elastic tension bands 2 and 3 are connected to the block 4 and the speed change pulley 21.
In addition to alleviating the impact caused by engagement with the block 4, the elastic tension bands 2 and 3 are hardly worn out, and no gap is created between the block 4 and the block 4, and the fixation of the block 4 is stabilized.
Since problems such as vibration do not occur, the noise of the V-belt 1 is reduced.

The V-belt 1 includes a block 4 and elastic tension bands 2 and 3.
While engaged with the speed change pulley 21, the respective side surfaces 4a, 4b are worn and corrected to fit the pulley grooves of the speed change pulley 21. Therefore, strict dimensional accuracy is not required for the block 4 and the elastic tension bands 2 and 3.

Further, the V-belt 1 is connected to the engagement groove 5 of the block 4,
The engagement protrusion provided on the lower surface of 6 and the elastic tension band 2,
Each block 4 is fixed to the elastic tension bands 2 and 3 in the length direction of the V-belt 1 by meshing with the engagement recess provided on the lower surface of the V-belt 1. , a phase difference is generated due to slippage at the interface between the elastic tension bands 2, 3 and the block 4, and the core bodies 7, 7 are pushed up by the reaction force of the rubber members 8, 9 at the portion sandwiched between the blocks 4, 4. , prevents the core bodies 7, 7 from becoming polygonal, and suppresses bending fatigue of the core bodies 7, 7. In addition, since the block 4 can be attached and detached in the width direction, assembly is extremely easy.
V-belts are cheaper.

Furthermore, the specific gravity of Block 4 is usually less than 2.0, which makes it extremely lightweight (1/5 to 1/5) compared to metal V-belts.
Since the centrifugal force is reduced at 1/4), it is suitable for high-speed operation and is highly safe.

Since the elastic tension bands 2 and 3 are shaped like thin flat belts, they have extremely good flexibility and generate little heat.
Belt life is extended.

In the above embodiment, the side surfaces 4a and 4b of the block 4
and a V-belt 1 that obtains friction transmission force with the speed change pulley 12 at the side surfaces 2a and 3a of the elastic tension bands 2 and 3.
However, it can also be applied to a V-belt that obtains the above-mentioned frictional transmission force only from the side surfaces of the blocks.

The V-belt of the present invention is not only used in continuously variable transmissions for automobiles, but also can be applied to V-belts for continuously variable or step-variable transmissions in vehicles equipped with engines such as agricultural machinery and civil engineering and construction machinery. I can do it.
It is also ideal for high-load V-belts in general industrial machinery driven by electric motors. Furthermore, the top surface of the block can be used as a belt for conveyance or printing.

(Effects of the invention) As described above, the present invention provides a lubricating resin layer on the inner surface of the engagement groove of the block body at least with which the elastic tension band comes into contact, so that wear of the elastic tension band is suppressed. Its premature breakage is prevented.

Further, an engagement recess is formed on the lower surface of the elastic tension band, and an engagement protrusion is formed on the lower surface of the engagement groove of the block, and when the elastic tension band is engaged with the engagement groove of the block, the elastic tension is applied. The engagement concave portion of the band and the engagement convex portion of the block engage, and the block is locked to the elastic tension band so that it can be attached and removed only in the width direction of the belt, so that the assembly of the elastic tension band and the block is easy. It is easy to attach and suppresses bending fatigue of the core of the elastic tension band.

[Brief explanation of the drawing]

Fig. 1 is a side view of a V-belt showing an embodiment of the present invention, Fig. 2 is a sectional view taken along the line - - in Fig. 1, Fig. 3 is a perspective view of a block used in the V-belt shown in Fig. FIG. 4 is a perspective view of an elastic tension band used in the V-belt shown in FIG. 1, and FIG. 5 is a sectional view showing a power transmission state in which the V-belt shown in FIG. 1 is engaged with a speed change pulley.
Figure 6 a and b are the Sa-Sa line and Sb-Sb in Figure 3.
The enlarged sectional view taken along lines in FIG. 7 is similar to FIG. 6b of a variant of the block. 1... V belt, 2, 3... Elastic tension band, 3
c, 3d...Engagement recess, 4...Block, 4A...
...Block body, 4B, 4D...Lubricating resin layer,
6c, 5d, 6d... Engaging convex portion, 7... Core body.

Claims (1)

[Claims for Utility Model Registration] (1) A utility model comprising a pair of endless elastic tension bands having a core and a plurality of blocks made of a non-metallic material and having engaging grooves opening on both sides, An engagement recess is formed on the lower surface of the elastic tension band, and an engagement protrusion is formed on the lower surface of the engagement groove of the block, and when the elastic tension band is engaged with the engagement groove of the block, the elastic tension band is formed. The engaging concave portion of the block is engaged with the engaging convex portion of the block, and the block is locked to the elastic tension band so that it can be attached and removed only in the belt width direction, and the block is connected to at least the elastic tension band of the block body. A V-belt, characterized in that a lubricating resin layer is provided on the inner surface of the engaging groove that comes in contact with the engaging groove. (2) The lubricating resin layer is formed of a resin made by blending a lubricating substance with the same base resin as the block body.
V-belt as described in section.