WO2010023824A1

WO2010023824A1 - V belt for transmitting heavy load

Info

Publication number: WO2010023824A1
Application number: PCT/JP2009/003693
Authority: WO
Inventors: 坂中宏行
Original assignee: バンドー化学株式会社
Priority date: 2008-08-27
Filing date: 2009-08-03
Publication date: 2010-03-04

Abstract

The V belt (B) for transmitting a heavy load has multiple blocks (10) and a pair of endless tensile bands (20). The upper surface of each engagement part (11) of each of the multiple blocks (10) is formed into a flat surface, while a convex engagement part (12) is formed on the lower surface. The upper surface of each pair of tensile bands (20) is formed into a flat surface, while the concave engagement parts (21), which engage with the convex engagement parts (12) formed on the lower surface of the engagement parts (11) of the blocks (10), are formed on the lower surface.

Description

V belt for high load transmission

The present invention relates to a V-belt for high load transmission and a belt transmission device using the same.

2. Description of the Related Art Belt-type continuously variable transmissions that can improve operability during shifting, improve fuel consumption rates, and the like are known as transmissions for agricultural machines, automobiles, and the like (for example, Patent Documents 1 to 3). . The V-belt for high load transmission used in such a belt-type continuously variable transmission has a configuration in which a number of blocks are locked and fixed in an endless tension band at intervals in the belt length direction. When wound on the pulley, both side surfaces can withstand high side pressure from the pulley.

Japanese Utility Model Publication No. 63-37845 JP 2000-120794 A Japanese Patent Laid-Open No. 9-25999

The inventor has conventionally considered that a mechanism in which a tension band fitted in a fitting portion of a block holds the block by fitting both the upper and lower projections and transmits torque is actually, The present inventors have found that the fitting of the unevenness on the lower side of the tension band plays most of the functions and arrived at the present invention.

The V belt for high load transmission of the present invention is
A plurality of blocks each having slit-shaped fitting portions that are open laterally on both sides in the belt width direction,
Each of a pair of endless tension bands fitted to connect the plurality of blocks to the fitting portions of the plurality of blocks,
With
Each of the plurality of blocks is configured such that the upper surface of each fitting portion is a flat surface and the fitting convex portion is formed on the lower surface,
Each of the pair of tension bands has a flat upper surface and is formed with a fitting recess on the lower surface to be fitted to the fitting convex portion on the lower surface of the fitting portion of the block.

The belt transmission device of the present invention has a continuously variable transmission mechanism configured by winding the V-belt for high load transmission of the present invention around a driving pulley and a driven pulley.

It is a perspective view of the V belt for high load transmission. It is II-II sectional drawing in FIG. It is a side view of a block. It is a side view of a tension belt. (A) And (b) is a figure which shows the pulley layout of a belt transmission. (A) And (b) is explanatory drawing which shows the effect | action of the force which rock | fluctuates a block with respect to a tension belt.

Hereinafter, embodiments will be described in detail based on the drawings.

1 and 2 show a high load transmission V-belt B according to the present embodiment. The high load transmission V-belt B is used for a belt-type continuously variable transmission in an agricultural machine, an automobile, or the like.

The high load transmission V-belt B according to the present embodiment has a configuration in which a plurality of blocks 10 are connected by a pair of endless tension bands 20 on both sides. The high load transmission V-belt B has, for example, a belt length of 450 to 750 mm and a belt pitch width of 20 to 30 mm. In the high load transmission V-belt B, for example, the number of blocks 10 is 90 to 375 and the block pitch is 2 to 5 mm.

FIG. 3 shows block 10.

Each block 10 is formed with a slit-like fitting portion 11 that opens laterally on both sides in the belt width direction of a trapezoidal plate-like body whose upper base is longer than the lower base in plan view. "Is arranged in a shape that the letter" "is horizontal. Each block 10 is formed so that the upper part from the fitting part 11 has a uniform thickness in a side view, while the lower part from the fitting part 11 becomes thinner as it goes downward. . Each block 10 has, for example, a height of 10 to 16.5 mm, a width of 20 to 30 mm, and a thickness of 2 to 5 mm. The angle formed by both sides, that is, the belt angle is, for example, 15 to 26 °.

Each fitting part 11 of each block 10 is formed so as to extend horizontally at a uniform interval from the back part on the center side toward the opening on the side part. Each fitting part 11 has a flat upper surface and a fitting convex part 12 formed of a protrusion having an arcuate cross section extending in the belt width direction on the lower side. Each fitting part 11 is comprised by the surface which the back part continued inclining to the back | inner side from the upper side surface, and the surface which continued to the surface, inclines outside, and continues to a lower side surface. Each fitting portion 11 is, for example, a belt thickness direction of the clearance gap _{t 1} is 1 ~ 3 mm, and the depth of the belt width direction is 2 ~ 5 mm. The fitting convex portion 12 has a radius of curvature of, for example, 1.0 to 1.5 mm.

Each block 10 has a configuration in which a metal reinforcing material 13 disposed in the center so as to form a skeleton is covered with a hard resin coating material. The entire metal reinforcing material 13 does not need to be covered with the hard resin coating material. It is sufficient that at least the contact portion with the tension band 20 and the pulley is covered, and the metal reinforcing material 13 is exposed in the other portions. It may be.

The metal reinforcing member 13 is formed in a shape that has the letter “H” beside it, like the block 10, and the center pillars 13c vertically move between the center portions of the upper and

lower beams

13a and 13b extending in the belt width direction. It has the structure connected to. The metal reinforcing material 13 is made of, for example, a lightweight aluminum alloy having high strength and high elastic modulus. In the metal reinforcing member 13, for example, the height of the upper beam 13a is 5.0 to 9.5 mm, and the height of the lower beam 13b is 5.0 to 9.5 mm.

The hard resin coating material is formed from, for example, a hard thermosetting phenol resin material, and aramid short fibers or milled carbon fibers may be mixed. The hard resin coating material has a layer thickness of, for example, 0.8 to 1.5 mm.

FIG. 4 shows the tension band 20.

Each tension band 20 is formed in an endless flat band shape. Each tension band 20 is chamfered on the upper side and the lower side so that one side corresponds to the shape of the back part of the block 10, and the other side corresponds to the inclination of the side part of the block 10. Formed on the inclined surface. Each tension band 20 has a flat upper surface, and fitting recesses 21 formed of circular arc grooves in the belt width direction are formed at a constant pitch in the belt length direction on the lower surface. Each tension band 20 has, for example, a length of 450 to 750 mm, a width of 20 to 30 mm, and a thickness of 2 to 5 mm. Particularly the thinnest portion (fitted into partial) _{t 2} is for example 1.0 ~ 3.0 mm in thickness in the fitting recess 21. The fitting concave portion 21 has a radius of curvature larger than that of the fitting convex portion 12, for example, 0.8 to 1.8 mm.

Each tension band 20 has a core wire 23 embedded in a spiral shape having a pitch in the belt width direction at the center of the shape retaining rubber layer 22 constituting the main body in the belt thickness direction. Each tension band 20 has an upper reinforcing cloth 24 on its upper side and a lower reinforcing cloth 25 on its lower side.

The shape-retaining rubber layer 22 is formed of a rubber composition using H-NBR, EPDM or the like as a raw rubber. The rubber composition constituting the shape-retaining rubber layer 22 is preferably reinforced by adding an unsaturated carboxylic acid metal salt such as zinc dimethacrylate or zinc diacrylate to the raw rubber. The rubber composition constituting the shape retaining rubber layer 22 is preferably reinforced by blending organic short fibers such as aramid short fibers and nylon short fibers in addition to carbon black or silica as a reinforcing material. Furthermore, the rubber composition constituting the shape-retaining rubber layer 22 is preferably crosslinked with an organic peroxide such as dicumyl peroxide. The rubber composition constituting the shape-retaining rubber layer 22 preferably has a rubber hardness of 75 ° or more as measured with a JIS-C hardness meter.

The core wire 23 is dipped in a resorcin / formalin latex aqueous solution (RFL aqueous solution) after being immersed in a twisted yarn or braid of high-strength fibers such as aramid fiber, PBO fiber, carbon fiber, etc. and / or dipped in rubber paste and then dried. It is made up of processed ones. The core wire 23 is composed of, for example, a filament bundle of 2640 to 4400 dtex and has an outer diameter of 0.55 to 0.70 mm.

Each of the upper and lower reinforcing

fabrics

24 and 25 is a process of heating after immersing in an RFL aqueous solution in woven fabric, knitted fabric, or non-woven fabric such as aramid fiber or nylon fiber, and / or dipping or coating rubber paste on rubber paste It is made up of those that have been subjected to a drying process. Each of the upper and lower reinforcing

cloths

24 and 25 has a thickness of, for example, 0.6 to 1.2 mm.

In this high load transmission V-belt B, a tension band 20 is fitted into the fitting portions 11 of the plurality of blocks 10 so as to connect them. Specifically, the tension band 20 is inserted into each fitting portion 11 of each block 10 from one side portion chamfered, and the upper side surface of the flat surface of the fitting portion 11 is the tension band 20. While being in contact with the upper side surface of the flat surface, the fitting convex portion 12 on the lower side surface of the fitting portion 11 is fitted into the fitting concave portion 21 on the lower side surface of the tension band 20 and tension is applied to the inner portion of the fitting portion 11. The tension band 20 is fitted in the fitting part 11 so that one side part of the band 20 contacts. As a result, the high load transmission V-belt B has a structure in which a plurality of blocks 10 are locked and fixed to the pair of tension bands 20 at intervals in the belt length direction. Moreover, the other side part of the tension | tensile_strength band 20 exposed to the both sides and the outer side of the some block 10 is comprised by the power transmission part which contacts a pulley. In this high load transmission V-belt B, the center of gravity of the block 10 is preferably on the belt pitch line.

In this high load transmission V-belt B, the gap t ₁ of the gap of the fitting portion 11 of the block 10 is slightly smaller than the thickness t ₂ of the fitting recess 21 of the tension band 20. Accordingly, the tension band 20 is fitted into the fitting portion 11 of the block 10 in a compressed state. Here, the tightening allowance t ₂ -t ₁ is, for example, 0.03 to 0.15 mm, and the tightening allowance is a ratio of the tightening allowance t ₂ -t ₁ to the gap t ₁ of the gap of the fitting portion 11 of the block 10. When the rate is expressed by α = {(t ₂ −t ₁ ) / t ₁ } × 100, α = 1 to 5% is preferable.

Further, in this high load transmission V-belt B, the tension band 20 is provided in a state of protruding from the side of the block 10, and thereby the impact when the high load transmission V-belt B enters the pulley. Can be relaxed by the tension band 20 protruding. Here, the allowance Δd is, for example, 0.03 to 0.15 mm, and the insertion pitch width w of the tension band 20 in the belt pitch line is, for example, 7.5 to 12.0 mm. The output allowance rate, which is the ratio of the output allowance Δd to the insertion pitch width of the tension band 20 at the tenth tension band engagement position (or half the block pitch width at the tension band engagement position of the block 10) w, is expressed as β = (Δd / When expressed as w) × 100, β is preferably 0.3 to 1.5%. Note that the allowance Δd can be easily measured by scanning the side surface of the V belt B for high load transmission with a tracer (contour shape measuring device).

5 (a) and 5 (b) show a belt transmission device 30 using the above-described high load transmission V-belt B. FIG.

The belt transmission device 30 includes a drive shaft 31 and a driven shaft 33 arranged in parallel thereto, a drive pulley 32 on the drive shaft 31, and a substantially the same diameter as the drive pulley 32 on the driven shaft 33. The following driven pulleys 34 are provided. The drive pulley 32 includes a fixed sheave that is rotatably and non-slidably fixed on the drive shaft 31, and a movable sheave that is rotatably and slidably supported so as to face the fixed sheave. ing. Similarly, the driven pulley 34 includes a fixed sheave that is rotatably and non-slidably fixed on the driven shaft 33, and a movable sheave that is rotatably and slidably supported so as to face the fixed sheave. It is equipped with. Each of the driving pulley 32 and the driven pulley 34 has a V-groove between the fixed sheave and the movable sheave, and the high load transmission V-belt B is bridged between the V-groove of the driving pulley 32 and the driven pulley 34. Has been. Each of the driving pulley 32 and the driven pulley 34 is configured to be variable within a pulley pitch diameter range of 55 to 155 mm.

In this belt transmission device 30, the power required for belt transmission is supplied on the drive shaft 31 side and consumed on the driven shaft 33 side, and the belt winding diameter of the drive pulley 32 and the belt winding diameter of the driven pulley 34 are also shown. Is changed so that the traveling speed of the high load transmission V-belt B is changed. Specifically, when the movable sheave of the drive pulley 32 is brought close to the fixed sheave and the movable sheave of the driven pulley 34 is moved away from the fixed sheave, as shown in FIG. This is larger than the belt winding diameter of the driven pulley 34. As a result, the high load transmission V-belt B travels at a high speed. Conversely, when the movable sheave of the drive pulley 32 is moved away from the fixed sheave and the movable sheave of the driven pulley 34 is moved closer to the fixed sheave, as shown in FIG. Becomes smaller than the belt winding diameter of the driven pulley 34. As a result, the high load transmission V-belt B travels at a low speed. That is, in the belt transmission device 30, the continuously variable transmission mechanism is configured with the above configuration.

By the way, in the conventional high-load power transmission V-belt, fitting protrusions are formed on each of the upper side and lower side of the fitting part of the block, and fitted on each of the upper side and lower side of the tension band. A concave portion is formed, and the block is locked and fixed to the tension band by fitting the fitting convex portion into the fitting concave portion at the top and bottom.

However, since the tension band is inserted into the fitting portion of the block in a compressed state, compression strain is always generated in the tension band, and repeated bending distortion is generated in the tension band during belt running. For this reason, the heat generation of the high load transmission V-belt during belt running is remarkable, and the thermal expansion of the tension band further increases the heat generation. And, during long-term use, the tension band becomes distorted due to permanent strain, so that a gap is created between the tension band and the block, increasing the degree of freedom of the block. There is a problem that it is damaged when input is made.

However, according to the high load transmission V-belt B of the present embodiment, as shown in FIG. 6A, the upper side surface of the fitting portion 11 of the block 10 is configured to be a flat surface, and the tension band 20 Since the upper side surface is configured as a flat surface, a convex portion is formed on the upper side surface of the fitting portion of the block 10 ′ shown in FIG. 6B, and the convex portion is fitted on the upper side surface of the tension band 20 ′. Compared to the conventional configuration in which the concave portion to be joined is formed, the distance l from the rotation center of the swing of the action point of the force F that swings the block 10 with respect to the tension band 20 in the portion wound around the pulley. Therefore, if the moments acting on the block 10 are the same, the force that causes the block 10 to swing with respect to the tension band 20 is small, so that damage to the block 10 can be suppressed. In addition, the height of the upper beam 13a of the metal reinforcing member 13 can be increased and the reinforcing effect can be increased by the amount that does not have the upper concave-convex fitting structure as compared with the conventional configuration.

Next, a method for manufacturing the high load transmission V-belt B will be described.

-Preparation process of sheet-like uncrosslinked rubber composition-
A raw material rubber is kneaded into a rubber kneading machine such as a Banbury mixer, and then a rubber compounding agent is added thereto and kneaded. Then, the kneaded uncrosslinked rubber composition is processed into a sheet by a calender roll.

-Core preparation process-
A cord 23 is obtained by subjecting a twisted yarn or braid to a treatment of heating after being immersed in an RFL aqueous solution and / or a treatment of drying after being immersed in rubber paste. In addition, you may perform the process dried after immersing in twisted yarn etc. in an epoxy solution or an isocyanate solution before these processes.

-Upper and lower reinforcing fabric preparation process-
Upper and lower reinforcing

cloths

24, 25, which are woven fabric, knitted fabric or non-woven fabric subjected to heating treatment after being immersed in an RFL aqueous solution and / or drying treatment after being immersed in rubber paste or coated with rubber paste, To do. In addition, you may perform the process dried after immersing in an epoxy solution or an isocyanate solution to a woven fabric etc. before these processes.

-Tension band forming process-
A cylindrical mold in which protrusions extending in the mold axial direction of the fitting recess shape of the tension band 20 are provided at an equal pitch in the circumferential direction is covered with a lower reinforcing cloth 25 formed in a cylindrical shape, and a sheet shape is formed thereon. An uncrosslinked rubber composition processed into a predetermined layer is provided.

Next, a cylindrical mold is placed in the heating and pressurizing apparatus, the interior of the apparatus is set to a predetermined temperature and pressure so that the crosslinking of the uncrosslinked rubber composition proceeds about half, and the state is maintained for a predetermined time. At this time, the cross-linking of the uncrosslinked rubber composition proceeds about half and the shape of the lower half of the shape-retaining rubber layer 22 is molded, and the uncrosslinked rubber composition flows and is provided in the cylindrical mold. The strip presses the lower reinforcing cloth 25 to form the fitting recess 21.

Subsequently, the cylindrical mold is taken out from the heating and pressurizing apparatus, the core wire 23 is spirally wound at an equal pitch from above the semi-crosslinked rubber composition, and the uncrosslinked rubber composition is processed into a sheet shape again thereon. A predetermined layer is provided, and an upper reinforcing cloth 24 formed in a cylindrical shape is placed thereon.

Next, a cylindrical sleeve with a flat inner peripheral surface is placed on the outermost layer.

Then, a cylindrical mold in which a material is set is placed in the heating and pressurizing device, the inside of the device is set to a predetermined temperature and pressure, and the state is maintained for a predetermined time. At this time, crosslinking of the semi-crosslinked and uncrosslinked rubber composition proceeds to form the shape retaining rubber layer 22. Further, the adhesive on the surface of the core wire 23 and the shape-retaining rubber layer 22 are mutually diffused so that the core wire 23 is integrally bonded to the shape-retaining rubber layer 22 and is attached to the upper and lower reinforcing

cloths

24 and 25. The upper and lower reinforcing

cloths

24 and 25 are integrally bonded to the shape-retaining rubber layer 22 by the mutual diffusion of the adhesive and the shape-retaining rubber layer 22. As described above, a cylindrical slab is formed on the surface of the cylindrical mold.

Finally, the cylindrical mold is taken out from the heating and pressurizing device, the cylindrical slab formed on the peripheral surface is removed from the mold, this is cut into a band with a predetermined width, and chamfering is performed. The tension band 20 is formed.

-Block molding process-
After the metal reinforcing material 13 is set in the cavity formed in the block mold and the mold is clamped, the hard resin coating material is injected into the cavity and then the mold is opened after cooling. The metal reinforcing material 13 is placed in the hard resin coating material. The block 10 which is the inserted molded product is taken out. And the various processing required in order to raise intensity | strength is given to the shape | molded block 10. FIG.

-Assembly process-
The fitting convex portion 12 of the block 10 is made to correspond to the fitting concave portion 21 of one tension band 20, and the fitting convex portion 12 of the block 10 is fitted into the fitting concave portion 21. The tension band 20 is inserted, and the block 10 is locked to the tension band 20. This operation is performed for the entire circumference of the tension band 20. Similarly, the other tension band 20 is inserted into the other fitting portion 11 of the block 10, thereby obtaining the high load transmission V-belt B.

(V-belt for high load transmission)
A V-belt for high load transmission for the following test evaluation was produced. Each configuration is also shown in Table 1.

<Example 1>
A V-belt for high load transmission having the same configuration as that of the above embodiment, the belt length is 612 mm, the belt angle is 26 °, the belt pitch width is 25 mm, the block pitch is 3 mm, the block thickness is 2.95 mm, the block The rubber composition of the rubber composition constituting the shape-retaining rubber layer of the tension band has a rubber hardness of 81 °, a tightening margin (t Example in which ₂₋ t ₁ ) is 0.05 mm, the tightening allowance α is 1.67%, the allowance Δd is 0.05 mm, the allowance β is 0.50%, and αβ is 0.83 It was set to 1.

<Example 2>
The tightening allowance (t ₂ -t ₁ ) is 0.03 mm and the tightening allowance rate α is 1.00%, the allowance allowance Δd is 0.06 mm, the allowance allowance β is 0.60%, and αβ is 0.60. Except for this, a V-belt for high load transmission having the same configuration as that of Example 1 was designated as Example 2.

<Example 3>
The tightening allowance (t ₂ -t ₁ ) is 0.06 mm and the tightening allowance rate α is 2.00%, the allowance Δd is 0.03 mm, the allowance allowance β is 0.30%, and αβ is 0.60. Except for this, a V-belt for high load transmission having the same configuration as that of Example 1 was designated as Example 3.

<Example 4>
The rubber composition of the shape-retaining rubber layer of the tension band has a rubber hardness measured by a JIS-C hardness meter of 75 °, an interference (t ₂ -t ₁ ) of 0.09 mm, and an interference margin α of 3.00. %, The output allowance Δd is 0.09 mm, the output allowance β is 0.90%, and αβ is 2.70, and the high load transmission V-belt having the same configuration as in Example 1 is did.

<Example 5>
The tightening allowance (t ₂ -t ₁ ) is 0.12 mm and the tightening allowance rate α is 4.00%, the allowance Δd is 0.12 mm, the allowance allowance β is 1.20%, and αβ is 4.80. Except for this, a V-belt for high load transmission having the same configuration as that of Example 1 was designated as Example 5.

<Example 6>
The fastening allowance (t ₂ -t ₁ ) is 0.10 mm, the fastening allowance rate α is 3.33%, the allowance Δd is 0.15 mm, the allowance allowance β is 1.50%, and αβ is 5.00. Except for this, a V-belt for high load transmission having the same configuration as that of Example 1 was designated as Example 6.

<Example 7>
The tightening allowance (t ₂ -t ₁ ) is 0.15 mm and the tightening allowance rate α is 5.00%, the allowance allowance Δd is 0.10 mm, the allowance allowance β is 1.00%, and αβ is 5.00. Except this, Example 7 is a high-load transmission V-belt having the same configuration as Example 1.

<Example 8>
The tightening allowance (t ₂ -t ₁ ) is 0.03 mm and the tightening allowance rate α is 1.00%, the allowance Δd is 0.14 mm, the allowance allowance β is 1.40%, and αβ is 1.40. Except for this, a V-belt for high load transmission having the same configuration as that of Example 1 was designated as Example 8.

<Example 9>
The tightening allowance (t ₂ -t ₁ ) is 0.14 mm, the tightening allowance rate α is 4.67%, the allowance Δd is 0.03 mm, the allowance allowance β is 0.30%, and αβ is 1.40. Except for this, a V-belt for high load transmission having the same configuration as in Example 1 was designated as Example 9.

<Example 10>
A high load transmission V-belt having the same configuration as that of Example 1 except that the block height was 11.5 mm was taken as Example 10.

<Example 11>
A high load transmission V-belt having the same configuration as that of Example 1 except that the upper beam height of the metal reinforcing material was 4 mm was taken as Example 11.

<Comparative Example 1>
The tightening allowance (t ₂ -t ₁ ) is 0.04 mm and the tightening allowance rate α is 1.33%, the allowance Δd is 0.04 mm, the allowance allowance β is 0.40%, and αβ is 0.53. The high load transmission V having the same configuration as in Example 1 except that a convex portion is formed on the upper side surface of the fitting portion of the block and a concave portion is formed on the upper side surface of the tension band. The belt was designated as Comparative Example 1.

<Comparative example 2>
The tightening allowance (t ₂ -t ₁ ) is 0.13 mm and the tightening allowance ratio α is 4.33%, the allowance allowance Δd is 0.14 mm, the allowance allowance β is 1.40%, and αβ is 6.07. The high load transmission V having the same configuration as in Example 1 except that a convex portion is formed on the upper side surface of the fitting portion of the block and a concave portion is formed on the upper side surface of the tension band. The belt was referred to as Comparative Example 2.

<Comparative Example 3>
The tightening allowance (t ₂ -t ₁ ) is 0.03 mm and the tightening allowance rate α is 1.00%, the allowance Δd is 0.17 mm, the allowance allowance β is 1.70%, and αβ is 1.70. The high load transmission V having the same configuration as in Example 1 except that a convex portion is formed on the upper side surface of the fitting portion of the block and a concave portion is formed on the upper side surface of the tension band. The belt was referred to as Comparative Example 3.

<Comparative example 4>
The fastening allowance (t ₂ -t ₁ ) is 0.17 mm, the fastening allowance rate α is 5.67%, the allowance Δd is 0.03 mm, the allowance allowance β is 0.30%, and αβ is 1.70. The high load transmission V having the same configuration as in Example 1 except that a convex portion is formed on the upper side surface of the fitting portion of the block and a concave portion is formed on the upper side surface of the tension band. The belt was referred to as Comparative Example 4.

<Comparative Example 5>
A high load transmission V-belt having the same configuration as that of the first embodiment except that a convex portion is formed on the upper side surface of the fitting portion of the block and a concave portion is formed on the upper side surface of the tension band. Was designated as Comparative Example 5.

<Comparative Example 6>
A convex portion is formed on the upper side surface of the fitting portion of the block, and a concave portion is formed on the upper side surface of the tension band, and a lower surface of the fitting portion of the block is formed on a flat surface. A high-load transmission V-belt having the same configuration as that of Example 1 except that the lower side surface is formed as a flat surface is referred to as Comparative Example 6.

(Test evaluation method)
The following belt running test was conducted using a belt running tester in which a driving pulley and a driven pulley were provided in the chamber.

<High speed heat resistance and high load durability test>
The high load transmission V-belts of Examples 1 to 11 and Comparative Examples 1 to 6 are wound around a drive pulley having a pulley pitch diameter of 133.6 mm and a driven pulley having a pulley pitch diameter of 61.4 mm, and the driven pulley is 2500 N The dead pulley was loaded and the driving pulley was rotated at a rotational speed of 5016 ± 60 rpm with a driving shaft torque of 70 N · m while blowing warm air of 120 ° C. into the chamber, and the maximum traveling time was 500 hours (Example 10 is 700). It was run until the belt broke down as time). The running time until the belt breaks was defined as a high speed heat resistant high load durability life.

<Low speed heat resistance and high load durability test>
The high load transmission V-belts of Examples 1 to 11 and Comparative Examples 1 to 6 are wound around a driving pulley having a pulley pitch diameter of 65.0 mm and a driven pulley having a pulley pitch diameter of 130.0 mm, and 4800 N around the driven pulley. A dead pulley of 90 ° C. was loaded into the chamber and the drive pulley was rotated at a rotational speed of 2600 ± 60 rpm with a drive shaft torque of 89 N · m while blowing 90 ° C. warm air into the chamber. It was run until the belt broke down as time). The running time until the belt breaks was defined as the low speed heat resistant high load durability test life.

<Transmission characteristics test>
The high load transmission V-belts of Examples 1 to 11 and Comparative Examples 1 to 6 are wound around a drive pulley having a pulley pitch diameter of 65.0 mm and a driven pulley having a pulley pitch diameter of 130.0 mm, and 4000 N around the driven pulley. The dead weight was loaded and the driving pulley was rotated at a rotation speed of 2600 ± 60 rpm while blowing warm air at 90 ° C. into the chamber, and the transmission characteristics were obtained with a slip ratio of 2%. In addition, the belt temperature at the beginning of running was measured.

(Test evaluation results)
The results are shown in Table 2.

The high-speed heat-resistant high-load durability life is 500 hours or more for Examples 1 to 11 (700 hours or more for Example 10), 300 hours for Comparative Example 1, 255 hours for Comparative Example 2, 230 hours for Comparative Example 3, Comparative Example 4 was 260 hours, Comparative Example 5 was 350 hours, and Comparative Example 6 was 200 hours. In all of Comparative Examples 1 to 6, the failure mode was block failure.

The low-speed heat-resistant and high-load durability life is 100 hours or more in Examples 1 to 11 (250 hours or more in Example 11), 50 hours in Comparative Example 1, 30 hours in Comparative Example 2, and 24 hours in Comparative Example 3. Comparative Example 4 was 30 hours, Comparative Example 5 was 70 hours, and Comparative Example 6 was 30 hours. In all of Comparative Examples 1 to 6, the failure mode was block failure.

The transmission characteristics are 83.0 N · m in Examples 1 to 9 and Comparative Examples 1 to 5, 86.0 N · m in Example 10, 90.0 N · m in Example 11, and 70.0 N · m in Comparative Example 6. m.

The belt temperature at the beginning of running was 106 ° C. in Example 1, 106 ° C. in Example 2, 105 ° C. in Example 3, 108 ° C. in Example 4, 108 ° C. in Example 5, 114 ° C. in Example 6. Example 7 was 115 ° C, Example 8 was 108 ° C, Example 9 was 110 ° C, Example 10 was 100 ° C, Example 11 was 110 ° C, and Comparative Example 1 was 110 ° C, and Comparative Example 2 was 145 ° C. Comparative Example 3 was 125 ° C., Comparative Example 4 was 145 ° C., Comparative Example 5 was 112 ° C., and Comparative Example 6 was 130 ° C.

From the above results, it can be seen that Examples 1 to 11 are more durable than Comparative Examples 1 to 6.

The present invention is useful for a V-belt for high load transmission and a belt transmission device using the same.

B High-load transmission V-belt 10 Block 11 Fitting part 12 Fitting convex part 13 Metal reinforcing material

13a Upper beam

13b Lower beam

13c Center pillar 20 Tension band 21 Fitting concave part 22 Shape-retaining rubber layer 23 Core wire 24 Upper reinforcing part Cloth 25 Lower reinforcing cloth 30 Belt transmission device 31 Drive shaft 32 Drive pulley 33 Drive shaft 34 Drive pulley

Claims

A plurality of blocks each having slit-shaped fitting portions that are open laterally on both sides in the belt width direction,
Each of a pair of endless tension bands fitted to connect the plurality of blocks to the fitting portions of the plurality of blocks,
With
Each of the plurality of blocks is configured such that the upper surface of each fitting portion is a flat surface and the fitting convex portion is formed on the lower surface,
Each of the pair of tension bands is configured such that the upper side surface is configured as a flat surface, and the lower side surface is formed with a fitting concave portion that fits into the fitting convex portion on the lower side surface of the fitting portion in the block. V belt for load transmission.
In the high load transmission V-belt according to claim 1,
Each of the plurality of blocks is a high load transmission V-belt whose center of gravity is on the belt pitch line.
In the high load transmission V-belt according to claim 1 or 2,
Α = {(t 2 −t 1 ) / t 1 , where t 1 is the gap between the fitting portions of the block, and t 2 is the thickness of the fitting portion of the tension band into the fitting portion of the block. } The fastening margin rate α represented by × 100 is 1 to 5%,
In addition, when the amount of protrusion of the tension band protruding from the fitting portion of the block is Δd and the insertion pitch width of the tension band at the tension band engagement position of the block is w, β = (Δd / w) The birth rate β expressed by × 100 is 0.3 to 1.5%,
Furthermore, a V-belt for high load transmission with α × β of 0.6 to 5.0.
In the high load transmission V-belt according to claim 3,
A high load transmission V-belt having a tightening allowance represented by t 2 -t 1 of 0.03 to 0.15 mm.
In the V belt for high load transmission according to claim 3 or 4,
A high-load power transmission V-belt with an allowance represented by Δd of 0.03 to 0.15 mm.
In the V belt for high load transmission according to any one of claims 3 to 5,
A V-belt for high load transmission having an insertion pitch width represented by w of 7.5 to 12.0 mm.
A belt transmission device having a continuously variable transmission mechanism in which the high-load transmission V-belt according to any one of claims 1 to 6 is wound around a driving pulley and a driven pulley.