JPH0554571B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a power transmission belt, and particularly to a V-shaped cog belt for high-load transmission, which has rigidity and is excellent in suppressing noise. (Prior art) Conventionally, V-shaped cog belts for power transmission have been manufactured by laminating and pasting rubberized canvas on the surfaces of upper and lower cushion rubber layers in which rope tensile members are buried in parallel, and forming a wave-shaped belt on the lower surface of the belt, that is, the contact surface with the pulley. Since the cog group is provided, the flexibility is good, but on the other hand, the cushion rubber of the cog part is usually flexible, so it fits into the pulley and falls into the pulley, reducing the transmission force due to deformation and causing early breakage. There were problems such as causes. Therefore, in order to improve the lateral pressure resistance of such belts, attempts have been made to use not only wood but also highly rigid metal rods, pipes, resin pipes, resin rods, etc. for the belt cogs. Due to the improvements in wood, the strength of wood is high, and when heat generation conditions due to belt slipping and bending on the pulley are added to resin, various properties are greatly reduced, making it unusable due to strength and abrasion.Especially when it comes to metal, aluminum It has been found that iron-based materials have various drawbacks such as abrasion resistance and difficulty in high-speed running due to their high specific gravity. Therefore, efforts for improvement were continued after that, and as shown in FIG. A high-load power transmission belt has been proposed in which reinforcing members 13 are arranged facing each other, and fixing members 14 such as bolts are used to penetrate the reinforcing plate, flat belt, and reinforcing members, and to integrally tighten and fix the reinforcing members 13. As part of this effort, we focused on the material of the cog-shaped block reinforcing material of the flat belt, and constructed the reinforcing material with trapezoidal blocks made by impregnating canvas with rubber or thermosetting resin and forming it into a spiral shape. Further proposals were made. (Akira Jigan
(No. 58-48727) (Problem to be solved by the invention) However, the most important quality required for a bolt-fastened block belt is rigidity, and the canvas impregnated with rubber or resin Blocks made by spirally winding materials have the advantage of being more rigid than ordinary resin-impregnated canvases laminated in parallel, but if the rigidity is too high, even if the transmission force increases, the noise will be louder. On the other hand, it has contradictory advantages and disadvantages, such as reducing the rigidity of the block in order to suppress sound production, which reduces the transmission force. Moreover, in the case of products that are directly wound into a spiral shape, in actual molding, winding into a spiral shape is troublesome and workability is poor.
The increased weight, increased cost, and inconvenience in handling were unavoidable. Thus, the present invention deals with the above-mentioned actual situation and focuses on the structure of the block, and unlike the above-mentioned proposal, which directly winds canvas impregnated with rubber or resin, it uses a core material. By making it possible to select materials for the core material and the canvas-imparting compound, it is possible to maintain rigidity and eliminate the above-mentioned drawbacks.
That is, the aim is to suppress noise, improve moldability, reduce cost, and reduce weight. (Means for Solving the Problems) That is, the present invention is characterized by attaching trapezoidal blocks to a flat belt in which rope tension members are embedded in parallel in a rubber-like elastic body using fastening materials such as bolts. In a belt that is fastened and fixed, the block is made of a material made of canvas impregnated with or adhered to a rubber compound, which has a built-in core material, and is wound and molded around the core material. Here, the core material and the canvas wrapped around the core material are important elements in the present invention, and the selection of the material is extremely important. Among these, the core material is useful for suppressing noise and is made of a rubber compound, the above-mentioned rubber compound in which short fibers are dispersed, or urethane rubber, etc., and the cross-sectional shape is not limited to circular or square but is irregular. . On the other hand, the canvas wound around the core material is made of cotton fiber, polyester fiber, synthetic fiber such as nylon, carbon fiber, glass fiber, metal fiber, etc.
A woven canvas made of a species or a mixture of two or more species,
This is provided with a rubber compound. Note that the rubber compound in the present invention refers to various rubber compounds that can be used for belt construction, such as chloroprene, hypalon, epichlorohydrin, natural rubber, SBR, and urethane rubber. Methods for applying the rubber compound to the canvas include a method of impregnating the canvas with rubber paste (spreading), a method of rubbing the rubber compound into the canvas (friction), and a method of coating the canvas (coating). There are methods such as impregnating urethane rubber with urethane rubber, which can be applied at any time. Thus, the trapezoidal block in the present invention is formed into a desired trapezoidal shape by wrapping canvas coated with the rubber compound around the core material,
It is fixed to a flat belt, but in this case, the type of rubber compound in the core material and the rubber compound-applied canvas are made different, for example, the core material is made of a low-rigidity material, such as a rubber compound with a hardness (JISA) of 90 degrees. On the other hand, using cotton fabric impregnated with hard rubber with a hardness (JISA) of 96° as the rubber compounded canvas is effective and suitable for increasing the rigidity of the block and suppressing noise. . Note that the trapezoidal blocks may be arranged only on either the upper or lower sides of the flat belt, or may be arranged on both the upper and lower sides. In this way, the power transmission belt as described above maintains its rigidity by using a swirl of canvas coated with a rubber compound, and also makes it easier to wrap around the core material, improving workability, and suppressing noise by appropriately selecting the core material. death,
This is extremely suitable as it allows the necessary friction coefficient of the block to be obtained. (Example) Hereinafter, further examples of the belt of the present invention will be described based on the accompanying drawings. FIG. 1 shows an example of a high-load power transmission belt according to the present invention. A single material such as SBR (styrene-butadiene rubber), CR (chloroprene rubber), NBR (nitrile rubber), IIR (butyl rubber), Hypalon (chlorosulfonated ethylene), or a blend of these as appropriate, or rubber such as polyurethane. Consisting of a rubber-like elastic body 1, usually
Although not particularly shown on the top surface, nylon canvas,
One or more layers, for example, one to three layers, of Kevlar (trade name) canvas or bias canvas or wide-angle canvas made of warp and warp yarn are laminated and stuck, and the elastic layer 1 contains polyester, aliphatic polyamide,
High strength, low elongation rope tensile material such as aromatic polyamide or glass fiber or wire strands 2
are buried spirally in parallel, and further below is a stretchable canvas made of the same material as the upper canvas or woven with woolly-processed crimped nylon warp and normal nylon weft. and,
Blocks 3 and 4, which are the characteristics of the present invention, are arranged above and below the flat belt b as described above at regular pitches along the longitudinal direction of the flat belt b, and fastening materials 5 made of bolts and nuts are attached to the blocks. Blocks 3 and 4 are connected to the flat belt b by penetrating them
4 is fixed. FIG. 2 shows each example of the block having the above structure, which is roughly divided into a core material 6 and a rubber compound-applied canvas 7 wound spirally around the core material 6, which is inserted into a block and placed on a predetermined stand. formed into a shape. Note that the block placed on the top surface may be plate-shaped as shown in FIG. Of course, a reinforcing plate can be used instead of the upper block. Accordingly, each structure of the block in FIG. is constructed by similarly wrapping canvas coated with a rubber compound around a core material 6 having a rectangular cross section. In each of the above examples, the core material 6 is formed of a molded body made of a selected rubber compound, but in Fig. A laminate is used as the core material 6, and a canvas 7 coated with the same or different rubber compound is wound around the core material 6. In addition, it goes without saying that the blocks are not limited to those described above, and that blocks can be constructed in various combinations without departing from the gist of the present invention. Further, although bolts and nuts are used as the fastening material 5 in the illustrated example, other means such as rivets may also be used. Furthermore, when tightening with bolts, rivets, or other fastening materials, it is desirable to use spring washers, flat washers, etc., as necessary, as this will improve the tightening effect. Thus, in the example of the invention, the trapezoidal blocks 3,
4 and the flat belt b are integrated by the fastening material 5,
The blocks 3 and 4 are prevented from falling off, fatigue of the rubber layer between the tensile member and the blocks is also prevented, and excellent lateral pressure resistance is maintained, and noise is suppressed, contributing to high load transmission. The above describes the case of a flat belt in which a low-elongation, high-strength rope tension body is spirally embedded in a rubber-like elastic body, and canvas layers are laminated and pasted on both the top and bottom surfaces. The same applies to a flat belt without a rope tension member, that is, a flat belt in which a rope tensile member is spirally embedded in a rubber-like elastic body, and the same applies to a state of fastening using a fastening material such as a bolt. Below, we conducted experiments using various block materials and compared the stiffness ratio and sound pressure.The results are shown below. The rigidity ratio is a value when the bending elastic modulus of rubber alone is assumed to be 1, and the sound pressure is expressed as the sound pressure at 5000 rpm when a belt using a block is applied to a pulley.

[Table] From the table above, the sound pressure of Nos. 2 and 3 according to the present invention has increased somewhat, but compared to the rate of increase in rigidity, the degree of increase is small and is almost the same as in the case of rubber only. It turns out that nothing changes. It should be noted that a spirally wound rubberized glass canvas has great rigidity, but the sound pressure is high, so it is acknowledged that there is a problem. (Effects of the Invention) As described above, in the power transmission belt of the present invention, a trapezoidal block made of canvas material impregnated with or adhered to a rubber compound and inserted in a spiral shape around a core material is attached to a flat belt. They are arranged at a predetermined pitch, and by applying a rubber compound to the canvas and rolling it in a spiral shape, it increases the lateral pressure resistance and rigidity, and has a remarkable effect on improving the durability of the belt. By incorporating the material, the following remarkable effects can be achieved. (a) First, when manufacturing this block, it is easier to wrap the block with the core material inside it than to simply wind the canvas impregnated with a rubber compound in a spiral shape, which improves work efficiency. At the same time, it becomes easier to maintain the uniformity of the spiral shape of the canvas, which in turn leads to uniform performance of the high-load power transmission belt. (b) Since the core material is included, the belt has high rigidity in the lateral direction, and the belt does not bend and fall into the pulley, and also prevents a reduction in belt transmission force and early breakage due to bending. I can do it. (c) The area around the core material is made of canvas impregnated with a rubber compound and formed into a spiral shape.
Its rigidity is lower than that of the core material, and noise caused by collisions with the pulley can be kept low. (d) Since the core material contains a rubber compound, it has a strong affinity with the rubber compound impregnated into the spirally wound canvas, so the core material does not peel off and can maintain sufficient rigidity. be. (e) By appropriately selecting the core material, it is possible to easily obtain the necessary friction coefficient of the block and to suppress the sound generation as much as possible.

[Brief explanation of drawings]

Fig. 1 is a partial perspective view of a high-load power transmission belt according to an example of the present invention, Fig. 2 A, B, and C are cross-sectional schematic diagrams showing each embodiment of a trapezoidal block, and Fig. 3 is a conventional block. FIG. 2 is a schematic cross-sectional view showing an example of a high-load power transmission belt in use. a...High load transmission belt, b...Flat belt, 1...
Rubber-like elastic body, 2... Rope tension body, 3, 4... Block, 5... Fastening material, 6... Core material, 7... Thermosetting resin impregnated canvas.

Claims (1)

[Scope of Claims] 1. A flat belt in which low elongation and high strength rope tensile bodies are embedded in parallel in a rubber-like elastic body, and trapezoidal blocks are attached to fixing materials such as bolts at predetermined pitches in the perpendicular direction along the longitudinal direction of the belt. In the belt, the block is made of a material obtained by applying a rubber compound to canvas and winding it in a spiral shape around a core material containing the rubber compound. A high-load transmission belt that is characterized by: 2. The high-load power transmission belt according to claim 1, in which canvas is impregnated with rubber glue and wound spirally around a core material. 3. The high-load power transmission belt according to claim 1, in which a rubber compound is rubbed into canvas and wound spirally around a core material. 4. The high-load power transmission belt according to claim 1, in which canvas is coated with a rubber compound and wound spirally around a core material. 5. The high-load power transmission belt according to claim 1, wherein canvas is impregnated with urethane rubber and wound spirally around a core material. 6. According to any one of claims 1 to 5, the canvas is made of at least one type of fiber selected from the group consisting of cotton fibers, synthetic fibers, glass fibers, carbon fibers, and metal fibers. High load transmission belt. 7. The polymer according to any one of claims 1 to 6, wherein the core material is made of at least one material selected from a rubber compound, the rubber compound in which staple fibers are dispersed, and urethane rubber. Load transmission belt. 8. The high-load power transmission belt according to any one of claims 1 to 7, wherein the core material has a circular or square cross-sectional shape.