JPH0237305Y2 - - Google Patents

Description

[Detailed explanation of the idea]

(Industrial Application Field) The present invention mainly relates to a toothed belt suitable for use in automobiles. (Prior art) In recent years, the requirements for the use conditions and durability of toothed belts used in automobiles have become increasingly strict due to improvements in engine performance, body shape, engine installation position, engine reliability, etc. However, since a toothed belt is a combination of multiple elastic materials, tensile materials, and cloth, its life cannot be extended unless the life of each member is balanced. However, although it is possible to develop elastic and tensile materials with excellent heat resistance and bending fatigue resistance, there has not been much progress in the fabric that protects the most important teeth of toothed belts. Woven fabrics made of polyamide fibers, which are most widely used at present, cannot meet these requirements, and the wear and thermal deterioration of the toothed fabrics have become the greatest weakness in the lifespan of toothed belts as composites. The reason for this is that the fabric layer of the tooth must have many properties, including not only heat resistance and wear resistance, but also bending fatigue resistance and flexibility at the root of the tooth when a load is applied to the tooth. This is because no material has been found that satisfies these requirements. (Problems to be Solved by the Invention) The present invention deals with the above-mentioned actual situation and aims to find the above-mentioned material, and to solve this problem. In other words, the inventors of the present invention endeavored to develop the above-mentioned material, and as a result of investigating and examining the heat generation of the toothed belt and the abrasion of the cloth layer in particular, they found that the surface temperature of the toothed belt was 20 to 30 degrees Celsius higher than the environmental temperature. It was speculated that the cause of this was internal heat generated by the bending of the toothed belt, and frictional heat generated when the teeth of the belt bit into the teeth of the pulley. Therefore, we focused on this frictional heat and conducted research to lower the friction coefficient of the cloth layer, and came up with the idea of using metal processing, leading to the present invention. Additionally, with regard to similarly lowering the coefficient of friction, the present applicant previously proposed that a protective cloth be formed by mixing some fibers with a lower coefficient of friction than normal fibers. Although this invention has the same purpose as the present invention, surface treatment with metal is not positively described. In contrast, the present invention aims to reduce the coefficient of friction by employing surface treatment using metal in the structure of the cloth layer. (Means for Solving the Problems) That is, the feature of the present invention is that the embodiments are shown in FIGS. 1 to 4 of the attached drawings. 4, a woven fabric with a friction coefficient of less than 0.3 is used as the cloth layer 4 that protects the toothed portion 3, and the warp extending in the longitudinal direction of the belt is made of metal thread, and the friction coefficient is less than 0.3. The point is that the coefficient of friction has been lowered. Here, the metal treatment on the surface of the cloth layer means that after weaving into the cloth,
It goes without saying that the surface of the woven fabric is metal-treated, but it is also possible to use a metal-treated yarn whose surface has been metal-treated on either or both of the warp and weft yarns constituting the cloth layer. In particular, when a metal thread is used on one side, it is preferable to use it as a thread along the length of the belt. Specifically, metal surface processing includes vacuum deposition,
These methods include sputtering, ion plating, and wet plating, among which vacuum deposition is the most practical. The metals used are Ni, Cu, Co, Cr, Ag,
Examples include Al. Note that polyamide threads, polyester fiber threads, etc. are commonly used as threads to be subjected to metal treatment, and these threads usually have a coefficient of friction of 0.3 to 0.4. (Function) The belt of the present invention has the above-mentioned structure, and to explain its function, the protective cloth has a low coefficient of friction due to the above-mentioned metal surface treatment, which is less than 0.3, preferably 0.25 or less. Cloth wear and heat generation when the pulleys engage are reduced, overall extending the life of the toothed belt and improving belt performance. (Embodiments) Hereinafter, embodiments of the toothed belt of the present invention will be described further based on the accompanying drawings. FIG. 1 is a schematic perspective view showing one example of a toothed belt according to the present invention, in which a is a toothed belt main body, 1 is a tensile body, and 2 is an elastic body in which the tensile body 1 is embedded. , 3 indicates tooth portions provided at regular intervals in the longitudinal direction of the belt, and 4 indicates a protective cloth layer. Here, the tensile rope 1 embedded spirally in parallel within the elastic body 2 is made of low elongation material selected from polyester, aliphatic polyamide, aromatic polyamide (trade name: Kevlar), glass fiber, wire, etc. The elastic body 2 is made of a high-strength rope tensile body, and the elastic body 2 covering this is made of NB (natural rubber), SBR
(styrene-butadiene rubber), CR (chloroprene rubber), NBR (nitrile rubber), IIR (butyl rubber),
Hypalon (chlorsulfonated polyethylene)
It is made of a single material such as rubber or a resin material such as polyurethane or a blend of these materials as appropriate. Further, the teeth 3 provided at regular intervals in the longitudinal direction of the belt are made of the same material as the elastic body. On the other hand, the protective cloth layer 4 is the main part of the present invention and is made of polyamide fiber yarn, polyester fiber yarn, etc.
For example, if a metal-processed thread, which is a metal-processed thread on the surface of an ordinary thread, is used as the warp 5 and the weft 6,
A canvas woven into a structure similar to that of a ro is used. As described above, this protective cloth layer 4 is not limited to the one in which metallized yarn is used together with the warp 5 and the weft 6, but metallized yarn may be used in only one of them. Fig. 3 shows an example in which a metal thread is used for only one of the threads, with the structure shown in Fig. 4, in which a metal thread is used only for the warp 5, and a normal thread is used for the weft 6. ing. Although not shown in the drawings, the protective cloth layer 4 may be further subjected to a surface treatment such as metal vacuum deposition on the surface of a cloth woven with ordinary threads. Next, a comparison between a specific example of the toothed belt of the present invention and a conventional toothed belt will be given. First, protective cloth layers No. 1 to No. 3 were prepared according to the table below, and were adhered to the surface of a toothed belt to evaluate belt performance. In addition, No. 2 nickel treatment and No. 2 according to the present invention.
Copper treatment in No. 3 was performed by vacuum evaporation. In addition, for evaluation, the number of teeth hobbed S45C
Number of teeth between 18 drive pulley and 36 tooth driven pulley
83, Belt size with belt width 19mm and tooth profile ZA
A 83ZA19 belt is stretched, a 60mmΦ tension pulley is placed in the middle, a tension of 15Kgf is applied, and the ambient temperature is 100℃ at 7200r.pm and a load of 5P/S.
The back surface of the belt was detected with a thermistor, the belt surface temperature was measured, and the coefficient of friction was further measured by the Roder method. The results are shown in the table below together with the protective fabric sample. In the table, N indicates nylon, PET indicates polyester fiber, and D indicates denier.

[Table] From the above table, it can be seen that the life of samples No. 2 and No. 3 according to the embodiment of the present invention is improved by about 1.4 to 1.6 times compared to the current product No. 1. (Effects of the invention) As described above, the present invention uses a woven fabric with a friction coefficient of less than 0.3, which uses metal-processed yarn in at least the warp extending in the longitudinal direction of the belt, as a protective fabric layer for the teeth of a toothed belt. Compared to the previous protective cloth layer, it takes advantage of the property of having a small coefficient of friction, which reduces cloth abrasion and heat generation caused by interference when belt teeth and pulleys mesh, prevents belt deterioration as a whole, and improves belt performance. In addition, the expected effect is that the belt life will be increased.

[Brief explanation of the drawing]

1 and 3 are partial schematic perspective views showing respective embodiments of the toothed belt according to the present invention, and FIGS.
In the figures, A and B are enlarged views of the structure of the fabric layer that constitutes the main part of the present invention, A is a plan view, and B is a sectional view taken along A-A of A. 1... Tensile body, 2... Elastic body, 3... Teeth, 4
...protective fabric layer, 5... warp, 6... weft.

Claims (1)

[Claims for Utility Model Registration] 1. A tensile body is embedded in an elastic body and has teeth at regular intervals in the longitudinal direction at right angles to the tensile body, and the surfaces of the teeth are covered and protected with a cloth layer. In a toothed belt, a metal-processed thread is used as the fabric layer for at least the warp threads extending in the belt length direction, and the friction coefficient is 0.3.
A toothed belt characterized by using a woven fabric with a lower coefficient of friction and lowering the coefficient of friction between the belt and the pulley. 2 Metal processing includes vacuum deposition, sputtering,
The toothed belt according to claim 1, which is a treatment selected from ion plating and wet metal coating. 3 The metal to be processed is Ni, Cu, Co, Cr, Ag,
The toothed belt according to any one of claims 1 to 2, which is a metal selected from the group consisting of Al.