JP2003314626A - Center belt for high-load transmitting belt and high-load transmitting belt - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a center belt for a high-load transmitting belt capable of preventing the joint part of a material constituting the center belt from cracking and precluding severance of the belt resulting therefrom. <P>SOLUTION: The center belt is for a high-load transmitting belt consisting of a plurality of blocks arranged in the longitudinal direction of the center belt and fitted fast, wherein at least its inner peripheral surface is formed so that the surface of a rubber sheet G1 furnished with grooves in the width direction is covered with a canvas C1, and the joint part J between the rubber sheet G1 and the canvas C1 is located in a position inside the grooves 19 in the center belt and contacting with ridges on the blocks. <P>COPYRIGHT: (C)2004,JPO

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 belt used for applications such as continuously variable transmissions such as automobiles, motorcycles, agricultural machinery, etc., in which blocks are arranged in a longitudinal direction on a center belt. The present invention relates to a center belt and a high-load transmission belt, and relates to a center belt and a high-load transmission belt for a long-life high-load transmission belt that prevent cracks from occurring in the center belt.

[0002]

2. Description of the Related Art A belt used in a belt type continuously variable transmission is used by being wound around a variable speed pulley in which the effective groove diameter of the pulley is changed by changing the V groove width of the pulley to adjust the gear ratio. However, since the lateral pressure from the pulley increases, the belt must withstand the large lateral pressure. Further, in addition to the use of continuously variable transmission, it is necessary to use a belt that can withstand a particularly high load for a high load transmission application in which the life of a normal rubber belt is too short.

Among such belts used is a high-load transmission belt in which a block is fixed to a center belt to increase the strength in the belt width direction. As a concrete structure, a core is made of rubber or the like. No. 63-34342, in which a block relatively harder than the rubber used in the center belt is fixed and fixed to the center belt embedded in the rubber by using a fastening material such as bolts and rivets. As shown, there is a belt which has grooves on both side surfaces of the block and in which a pair of center belts are fitted in the grooves provided on the side surfaces.

The center belt used for such a belt is a member that bears tension, has a core wire of high strength and low elongation embedded in rubber, and is fitted to a block on the inner and outer peripheral surfaces of the center belt. The concave portions and the convex portions are alternately provided. For example, convex portions are provided in the grooves on both side surfaces of the block at positions corresponding to the concave portions of the center belt, and when the blocks are fitted to each other, the blocks do not move in the traveling direction of the high load transmission belt with respect to the center belt. It is fixed.

A cover canvas is laminated on the surface of the center belt for reinforcement. In addition, such a center belt is originally made endless by winding an endless rubber sheet or cover canvas around a cylindrical mold and joining the ends, and conventionally the joint between the rubber sheet and the cover canvas is Both are butt jointed.

[0006]

However, since the rubber is almost integrated by vulcanization, a sufficient joining strength can be obtained, but the cover canvas remains as a butt joint portion without being integrated. become.
When the joint part is repeatedly subjected to a large force from a block or the like and is repeatedly bent, the joint part comes off and the cover canvas peels off from the rubber, and as a result, the cover canvas is no longer reinforced, resulting in the rubber material forming the center belt. However, there is a problem that the rubber is exposed and cracks occur in the rubber that constitutes the main body of the belt, which eventually leads to the cutting of the belt.

Therefore, the present invention solves the problem that the cover canvas provided on the center belt is prevented from being detached or peeled off at the joint portion, and by doing so, the rubber portion is cracked and the belt is cut. The purpose is to provide a high-load transmission belt with a long life.

[0008]

In order to achieve the above object, in claim 1 of the present invention, a center belt having a core body embedded in rubber, and a plurality of center belts are fitted along the longitudinal direction of the center belt. A center belt used for a high-load transmission belt composed of a block fixed together, at least the inner peripheral side of which is composed of a cover sheet covering the surface of a rubber sheet provided with widthwise recesses at a predetermined pitch, In a center belt for a high load transmission belt, in which the rubber sheet and the cover canvas are jointed at at least one place, in the recessed portion provided on the inner peripheral side of the center belt, and fitted with the recessed portion when the block is mounted. It is characterized in that the joint portion of the rubber sheet is arranged at a position in contact with the ridge portion of the block.

By arranging the joint portion of the rubber sheet in such a position as to come into contact with the ridge portion of the block as described above, the joint portion is always held by the block. It bends between the blocks, and the joint part that is in contact with the ridges of the block does not put too much strain on it even when it is bent, and even if a crack occurs, the center belt cuts from it. You will never reach the situation where you do.

According to the second aspect of the present invention, the center portion for the high load transmission belt is formed by disposing the joint portion of the rubber sheet and the joint portion of the cover canvas at different positions.

By displacing the joint portion of the cover canvas in this manner, problems such as detachment and peeling at the joint portion of the cover canvas are prevented, and even if the cover canvas is detached or peeled and the rubber is exposed,
Since the rubber joint is not exposed, it is possible to prevent cracks from occurring in the rubber joint, and it is possible to prevent the belt from being cut, so that the life can be extended.

According to a third aspect of the present invention, there is provided a high load transmission belt comprising a center belt having a core body embedded in rubber, and a plurality of blocks fitted and fixed along the longitudinal direction of the center belt. The peripheral side is composed of a cover sheet covering the surface of a rubber sheet having recesses in the width direction at a predetermined pitch, and the rubber sheet and the cover sheet are jointed at at least one place in a high-load transmission belt. It is characterized in that the joint portion of the rubber sheet is arranged at a position in the concave portion provided on the inner peripheral side of the belt and in contact with the convex portion of the block fitted with the concave portion when the block is mounted. .

By arranging the joint portion of the rubber sheet in such a position as to come into contact with the ridge portion of the block as in the first aspect, the joint portion is always suppressed by the block. When the is bent, the rubber bends between the blocks,
The joint part that is in contact with the ridges of the block does not put too much load on the joint even when bent, and even if a crack occurs, the center belt will be cut from there. There is no.

According to a fourth aspect of the present invention, the high load transmission belt has the joint portion of the rubber sheet and the joint portion of the cover canvas arranged at different positions.

By displacing the position of the joint portion of the cover canvas as in the second aspect, problems such as detachment and peeling at the joint portion of the cover canvas are prevented,
Even if the cover canvas is peeled off or peeled off and the rubber is exposed, the joint part of the rubber is not exposed.
Since it is possible to prevent cracks from occurring in the rubber joint portion and further prevent cutting of the belt, it is possible to prolong the service life.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be specifically described below with reference to the drawings.

FIG. 1 is a perspective schematic view showing an example of a high load transmission belt 1 using a center belt manufactured by the method of the present invention, and FIG. 2 is a sectional view of the center belt. A high load transmission belt 1 using a center belt manufactured by the method for manufacturing a center belt for a high load transmission belt of the present invention has a rubber-like core 5 having a rope-shaped core body 5 embedded in a spiral shape and having the same width. Two center belts 3a,
3b and center belts 3a and 3b on the side surfaces 2a and 2b.
It is composed of a block 2 having grooves 14 and 15 in which are fitted.

Upper and lower surfaces 2 of the center belts 3a and 3b
It is locked and fixed in the groove portions 14 and 15 of the block 2 in the groove portions 18 and 19 formed at a predetermined pitch in the groove portions 2 and 23 as described later. Both side surfaces 2a, 2b of the block 2 are inclined surfaces that engage with the V groove of the pulley, and receive the power from the driven pulley to lock and fix the center belt 3
Power of the drive pulley is transmitted to the driven pulley by pulling a and 3b. Further, canvases 24, 25 may be laminated on the upper and lower surfaces of the center belts 3a, 3b.

As shown in FIG. 1, the block 2 includes an upper beam portion 11 and a lower beam portion 12, an upper and lower beam portions 11,
The center pillars 13 are formed by connecting the central portions of the blocks 12 to each other.
Grooves 14 and 15 into which a and 3b are fitted are formed. Further, as shown in FIG. 2, on the groove upper surface 16 and the groove lower surface 17 in the groove 15, there are convex stripes that engage with the concave stripes 18 provided on the upper surface 22 of the center belt 3 and the concave stripes 19 provided on the lower surface 23. Part 2
0, 21 are provided so that the block 2 and the center belts 3a, 3b are locked and fixed.

As shown in FIG. 2, the center belts 3a and 3b have a core body 5 buried substantially in the center in the thickness direction of the center belt, and are located on the inner layer 4a located on the inner peripheral side and on the outer peripheral side thereof. It consists of an outer layer 4b.

Such a center belt for a high load transmission belt is manufactured by the following steps. FIG. 3 is a side view of the joint of the composite sheet H on the inner die. The inner layer 4a has a cover canvas C on one side of the rubber sheet G1.
The rubber sheet G1 is made to have a thickness larger than a predetermined thickness by first rolling, and the cover canvas C1 is laminated. Then, a concave streak portion 1 for fitting the block on the surface where the cover canvas C1 is laminated by pressing
Composite sheet H which becomes inner layer 4a by forming 9
Is completed.

Next, the composite sheet H is wound around an inner mold 40 having a cylindrical shape and having a convex shape which is fitted around the concave stripe portion of the composite sheet H. A rubber sheet G in which the core wire 5 is spirally wound from above to form the outer layer 4b from above.
2. Wrap the cover canvas C2. Then, the center belt 2 is completed by covering the inner surface with an outer mold (not shown) having a convex shape as needed and vulcanizing by heating and pressing.

As described above, the inner layer 4a joins the endless composite sheet H in an endless manner on a cylindrical inner die, but in the present invention, it is within the groove 19 formed on one side of the inner layer 4a. The block is joined at a position where it comes into contact with the ridge portion 21 of the block fitted when the block is mounted.

Such a rubber center belt 3a,
In a belt in which many blocks 2 are fitted to 3b,
When the belt is wound around the pulley, it is between the blocks 2 and 2 that the center belts 3a and 3b are bent.
It can be said that the portion where the block 2 is fitted and in contact is a portion that is less likely to be bent and deformed while the belt is running. Therefore, by arranging the joint portion J of the composite sheet H forming the center belts 3a and 3b at that portion, it is possible to prevent a problem such as a crack from the joint portion J.

The composite sheet H is composed of a rubber sheet G1 portion and a cover canvas C1 portion. In Claims 2 and 4 of the present invention, the joint portion J1 of the rubber sheet G1 and the cover canvas C1 are further included. The joint part J2 is arranged at a different position.

When the joint portion J1 of the rubber sheet G1 and the joint portion J2 of the cover cloth C1 are in the same position, the joint portion J1 of the rubber cover sheet G1 is exposed when the joint portion J2 of the cover cloth C1 is cracked and opened. Then, it will rub against the ridge 21 of the block,
Although it is vulcanized and almost integrated, there is a high possibility that a problem may occur such that a crack is generated from the joint portion J1 that is weaker than other portions. However, the rubber sheet G
By arranging the joint part J1 of No. 1 and the joint part J2 of the cover canvas C1 at different positions, the joint part J1 of the rubber sheet G1 may be exposed even if the joint part J2 of the cover canvas C1 is opened. Therefore, the state protected by the cover canvas C1 can be maintained as usual.

The joint portion J1 of the rubber sheet G1 and the joint portion J2 of the cover canvas are at different positions, both of which are in the recessed portion 19 of the center belt 2 and in contact with the protruding portion 21 of the block 2. Positioning is the most preferred form.

The joint portion J1 of the rubber sheet G1 is arranged at a position in contact with the ridge portion 21 of the block, and the joint portion J2 of the cover canvas C1 is similarly arranged in the ridge portion 21 of the block.
At the position where it contacts with the joint part J of the rubber sheet
By disposing the cover sheet at a position different from 1, it is possible to prevent the joint portion J2 of the cover canvas from cracking, and even if the joint portion J2 of the cover canvas G1 cracks, the rubber sheet G
It is possible to avoid the situation in which the joint portion J1 of No. 1 is exposed and the joint portion J1 of the rubber sheet G1 is also suppressed by the projecting ridge portion 21 of the block, so that the joint portion J1 of the rubber sheet G1 is temporarily cracked. Even if it is possible, it is possible to prevent the crack from proceeding from there to cutting.

The method of heating / pressurizing is not particularly limited, and may be a method of covering with a jacket and putting it in a vulcanization can by steam, or a method of using a mold further provided with an electric heater from the outside. I do not care.

According to the present invention, the joint portion J of the composite sheet H when the inner layer 4a of the center belt is formed is located in the recessed portion 19 of the center belt and the protruding portion 21 of the block 2.
It is intended to prevent the problem such as the cutting caused by the crack from the joint portion J of the inner layer 4a of the center belt by arranging it in the position where it comes into contact with, and does not limit other steps in the manufacturing process. Absent.

The high load transmission belt 1 can be finally obtained by fitting the block 2 into the groove portions 18 and 19 of the center belt obtained as described above.

FIG. 5 shows another form of the present invention.
In the joint portion J, the joint portion J1 of the rubber sheet G1 is butted as in the above-mentioned example, but the joint portion J2 of the cover canvas C1 is lap jointed, which has the advantage that cracks are less likely to occur at the joint portion J2. I have.

FIG. 6 shows an example of another belt to which the center belt obtained by the manufacturing method of the present invention can be applied, in which the pair of side pillars 32, 33 are arranged upward from both ends of the beam portion 31. It extends and this side pillar 3
Lock parts 34 and 35 extending from the upper ends of the blocks 2 and 33 toward the center of the block 2 are provided so as to face each other. And these beam part 31 and side pillar 3
A fitting groove 30 into which the center belts 3a and 3b are fitted is formed by the reference numerals 2, 33 and the lock portions 34, 35.
The center belts 3a and 3b are inserted into the fitting groove 30 through the opening between the lock portions 34 and 35 and mounted. Further, on the fitting groove 30 side of the lock portions 34 and 35, the convex portion 37 is provided.
Are provided in the center belts 3a and 3b at predetermined pitches.
Fit to 6. As a result, the center belts 3a, 3
After mounting, b is in a state where it is hard to come off from the block 2.

Further, either a block in which an insert material such as an aluminum alloy is embedded or a block in which no insert material is embedded can be used.

Polyamide resin, polyamideimide (PAI) resin, polyphenylene sulfide (PPS) resin, polybutylene terephthalate (PBT) resin, polyimide (P) can be used as the block resin.
Synthetic resins such as I) resin, polyether sulfone (PES) resin, and polyether ether ketone (PEEK) resin are used. Among them, they have a low friction coefficient, excellent wear resistance, rigidity and elasticity against bending. It is preferable to use a resin that has properties and is not easily broken, and a polyamide resin, particularly nylon 46 is preferable.

In the present invention, it is possible to mix a fibrous reinforcing material or a whisker-like reinforcing material in the synthetic resin forming the block as described above, and the fibrous reinforcing material is 15 to 4
It is compounded in the range of 0% by weight. If it is less than 15% by weight, there is a problem that the reinforcing effect is small and the abrasion resistance of the block is not sufficient, and if it exceeds 40% by weight, it becomes difficult to mix it with the resin and injection molding becomes difficult. There is a problem, so it is not preferable.

Examples of the fibrous reinforcing material to be mixed with the synthetic resin include aramid fiber, carbon fiber, glass fiber, polyamide fiber, polyester fiber and the like. Among them, by using nylon 46, which is a preferable example of the resin forming the block, and carbon fiber in combination, the carbon fiber can improve the water absorption defect of nylon 46 and significantly improve the rigidity, In addition, the wear resistance, impact resistance, and fatigue resistance of nylon 46 can be fully utilized.

In addition to the above organic fibers, inorganic fibers such as zinc oxide whiskers, potassium titanate whiskers and aluminum borate whiskers may be blended as the fibrous reinforcing material.

Further, since the zinc oxide whiskers have a high specific gravity and a high rigidity, it is possible to reduce vibration at the time of contact with the pulley and to reduce noise generation. If the amount of this zinc oxide whisker is small, the effect of addition will not be exhibited, and if it is too large, kneading will not be possible and molding will be difficult.

By adopting such a material constitution,
It has strength such as rigidity and toughness that can withstand the lateral pressure that it receives when it comes into contact with the pulley, and it has excellent wear resistance.
Furthermore, it becomes possible to form a block that is strong against heat generated during friction, and the power received from the pulleys can be efficiently transmitted to the center belts 3a and 3b as a tensile force, and a tension transmission type high load transmission belt. Can be configured.

In addition to these, molybdenum disulfide,
The lubricity of the block 2 can also be improved by mixing at least one selected from graphite and fluorine resin. Examples of the fluorine-based resin include polytetrafluoroethylene (PTFE), polyfluoroethylene propylene ether (PFPE), tetrafluoroethylene hexafluoropropylene copolymer (PFEP), polyfluoroalkoxyethylene (PFA), and the like. .

What is used as the rubber 4 of the center belts 3a, 3b is a single material such as chloroprene rubber, natural rubber, nitrile rubber, styrene-butadiene rubber, hydrogenated nitrile rubber, or a rubber or polyurethane in which these are appropriately blended. Examples thereof include rubber. As the core body 5, a rope selected from polyester fiber, polyamide fiber, aramid fiber, glass fiber, steel wire and the like is used.

[0043]

As described above, according to the first aspect of the present invention, a high load transmission including a center belt having a core body embedded in rubber and a plurality of blocks fitted and fixed along the longitudinal direction of the center belt. A center belt used as a belt, wherein at least the inner peripheral side is constituted by a structure in which a cover canvas is coated on the surface of a rubber sheet provided with widthwise recesses at a predetermined pitch, and the rubber sheet and the cover canvas are at least at one location In a center belt for a high load transmission belt, which is jointed with, a position in the concave portion provided on the inner peripheral side of the center belt, which comes into contact with the convex portion of the block that fits with the concave portion when the block is mounted It is characterized in that the joint part of the rubber sheet is arranged in.

By arranging the joint portion of the rubber sheet in such a position as to come into contact with the ridge portion of the block as described above, the joint portion is always held by the block, so that the rubber is not bent when the belt bends. It bends between the blocks, and the joint part that is in contact with the ridges of the block does not put too much strain on it even when it is bent, and even if a crack occurs, the center belt cuts from it. You will never reach the situation where you do.

According to a second aspect of the invention, a center belt for a high load transmission belt is provided in which the joint portion of the rubber sheet and the joint portion of the cover canvas are arranged at different positions.

By displacing the position of the joint portion of the cover canvas in this way, problems such as detachment and peeling at the joint portion of the cover canvas are prevented, and even if the cover canvas is detached or peeled and the rubber is exposed,
Since the rubber joint is not exposed, it is possible to prevent cracks from occurring in the rubber joint, and it is possible to prevent the belt from being cut, so that the life can be extended.

According to a third aspect of the present invention, there is provided a high load transmission belt comprising a center belt having a core body embedded in rubber and a plurality of blocks fitted and fixed along the longitudinal direction of the center belt. The circumferential side is composed of a cover sheet covering the surface of a rubber sheet provided with a widthwise recessed portion at a predetermined pitch. The rubber sheet and the cover sheet are joined together in at least one place in a high load transmission belt. It is characterized in that the joint portion of the rubber sheet is arranged at a position in the concave portion provided on the inner peripheral side of the belt and in contact with the convex portion of the block fitted with the concave portion when the block is mounted. .

By arranging the joint portion of the rubber sheet in such a position as to contact the ridge portion of the block as in the first aspect, the joint portion is always held by the block. When the is bent, the rubber bends between the blocks,
The joint that is in contact with the ridges of the block does not put too much load on the joint even when it bends, and even if a crack occurs, the center belt will be cut from there. There is no.

According to a fourth aspect of the present invention, the high load transmission belt has the joint portion of the rubber sheet and the joint portion of the cover canvas arranged at different positions.

By displacing the position of the joint portion of the cover canvas as in the second aspect, problems such as detachment and peeling at the joint portion of the cover canvas are prevented,
Even if the cover canvas is peeled off or peeled off and the rubber is exposed, the joint part of the rubber is not exposed.
Since it is possible to prevent cracks from occurring in the rubber joint portion and further prevent cutting of the belt, it is possible to prolong the service life.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing an example of a high load transmission belt according to the present invention.

FIG. 2 is a side sectional view of a high load transmission belt.

FIG. 3 is a cross-sectional view of a composite sheet wound around an inner mold.

FIG. 4 is a cross-sectional view in which a core body, a rubber sheet on the outer layer side and a cover canvas are further wound around an inner mold.

FIG. 5 is a cross-sectional view corresponding to FIG. 3 showing another example of the present invention.

FIG. 6 is a schematic perspective view showing another example of the high load transmission belt according to the present invention.

[Explanation of symbols]

1 High load transmission belt 2 blocks 3a Center belt 3b center belt 4 rubber 4a inner layer 4b outer layer 5 mind and body 11 Upper beam section 12 Lower beam part 13 center pillars 14 groove 15 grooves 16 groove top 17 Lower surface of groove 18 Recessed part 19 Recess 20 ridge 21 ridge G1 rubber sheet G2 rubber sheet C1 cover canvas C2 cover canvas H composite sheet J joint section J1 joint section J2 joint section

Claims (4)

[Claims] 1. A center belt for use in a high load transmission belt comprising a center belt having a core body embedded in rubber and a plurality of blocks fitted and fixed along the longitudinal direction of the center belt, the center belt having at least an inner circumference. In the center belt for a high load transmission belt, the side is formed by covering the surface of a rubber sheet provided with concave portions in the width direction at a predetermined pitch with a cover canvas, and the rubber sheet and the cover canvas are jointed at at least one place. The joint portion of the rubber sheet is arranged at a position in the recessed portion provided on the inner peripheral side of the center belt and in contact with the protruding portion of the block fitted with the recessed portion when the block is mounted. A center belt for high load transmission belts. 2. The center belt for a high load transmission belt according to claim 1, wherein the joint portion of the rubber sheet and the joint portion of the cover canvas are arranged at different positions. 3. A high load transmission belt comprising a center belt having a core body embedded in rubber and a plurality of blocks fitted and fixed along the longitudinal direction of the center belt, wherein the inner peripheral side of the center belt is In a high-load transmission belt in which a cover canvas is covered on the surface of a rubber sheet provided with recessed portions in the width direction at a predetermined pitch, and the rubber sheet and the cover canvas are jointed at at least one place, a center belt inner circumference A high load transmission characterized in that a joint portion of a rubber sheet is arranged at a position in the concave portion provided on the side and in contact with the convex portion of the block fitted with the concave portion when the block is mounted. belt. 4. The high load transmission belt according to claim 4, wherein the joint portion of the rubber sheet and the joint portion of the cover canvas are arranged at different positions.