JPH0538264Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a toothed belt having a toothed cloth coated on the surface of the toothed portion, and particularly to an improvement of the toothed cloth of a toothed belt for automobiles. .

(Prior art) Toothed belts generally receive the load from the pulley on the teeth, so the teeth are made of an elastic elastomer material and a stretchable cloth covering the surface.
In addition, due to the high speed rotation of the engine, each tooth section is repeatedly deformed hundreds to thousands of times per minute, so it is necessary to firmly bond the tooth cloth to the elastic elastomer material, so the tooth cloth is impregnated with adhesive and elastomer material. Generally, it is used after being treated to

(Problem that the invention aims to solve) However, in recent years, with the improvement of engine performance, the usage conditions for toothed belts for automobiles have become harsher, and the tooth cloth that protects the toothed belt part from high heat has become particularly harsh. There are many cases where the teeth are damaged due to thermal deterioration and wear, shortening the life of the belt.

Therefore, as a preventive measure, the
- It has been proposed to apply ceramic powder to the surface of the tooth cloth as in No. 1253, but as the running time increases, the surface of the pulley is ground and forms small streaks or grooves, which causes the skin roughening phenomenon of the pulley. It has been found that the tooth cloth is scraped, and sometimes the grinding debris of the tooth cloth sticks to the pulley surface, assisting the grinding of the new tooth cloth, rapidly reducing the belt life and causing early breakage.

The present invention addresses the above-mentioned circumstances and aims to improve the problem by preventing the roughening phenomenon of the toothed belt pulley and improving the wear resistance of the toothed portion of the toothed belt. The purpose of this method is to mix short fiber powder into the elastomer material that is coated or impregnated in the tooth cloth to reduce roughness (damage) of the toothed belt, reduce fatigue and wear of the tooth cloth, and improve the belt life. It is something to do.

(Means for Solving the Problems) Therefore, the feature of the present invention, which is suitable for the above-mentioned purpose and aims to solve the above-mentioned problems, is that in the above-mentioned toothed belt, short fiber powder such as short fiber powder is used as the tooth cloth. This method uses a canvas coated with an elastomer material mixed with an abrasion-resistant substance by coating or impregnation.

Here, the above-mentioned feature is that the atmospheric temperature is
Drive pulley (number of teeth 18T, rotation speed
7200R.PM) and driven pulley (36T, 3600R.PM)
Size 83ZA19 (number of teeth 83, tooth profile ZA, belt width)
This is based on the results of observing the state of damage to the tooth cloth by suspending a toothed belt (19 mm) with a 52 mm tension pulley and running under a load of 5 P/S. It has been found that by mixing various short fiber powders into the belt, damage to the tooth cloth can be prevented and the belt life can be increased.

Here, the short fiber powder mixed as the wear-resistant substance is typically glass fiber, glass beads, carbon fiber, or aramid fiber, but is not particularly restricted thereto.

Regarding the length and amount of these short fiber powders, if the length is less than 0.5μ, the short fibers will be less exposed to the surface and the effect will be poor, and if the length is more than 10mm, the dispersion state in the elastomer will be insufficient. It becomes uniform and the wear resistance effect decreases.

On the other hand, if the amount of the mixture is less than 3%, the probability that it will appear on the surface of the elastic body is small and the reinforcing effect will be low.If the amount is more than 35%, it will be difficult to apply the coating uniformly to the surface of the canvas, and the amount of adhesion on the bottom of the teeth will be uneven. With belt
Increasing the variation in PLD and causing malalignment,
Extremely reduces belt life.

Therefore, the length of the short fiber powder to be mixed is as follows:
It is preferably about 0.5 μm to 10 mm, and the amount mixed is preferably about 3 to 35% by volume based on 100 parts of the elastomer material.

On the other hand, examples of elastomer materials mixed with short fiber powder include CR (chloroprene rubber), NBR (nitrile rubber), H-NBR (hydrogenated nitrile rubber), and CSM.
(chlorosulfonated polyethylene rubber), CHM
Synthetic rubbers include (epichlorohydrin rubber), ACM (acrylic rubber), and polyurethane.
These can be used alone or in a blend.

(Example) Hereinafter, an example of the toothed belt of the present invention will be described with reference to the attached drawings.

FIG. 1 shows an example of a toothed belt according to the present invention, and in the figure, a indicates the toothed belt main body, and the belt a has a low elongation, high strength rope tensile body 1 spirally stretched with a rubber layer. 2, and the tooth portion 3 is formed on the lower surface (the upper surface is shown for convenience of explanation in the figure) of the same rubber as the extension rubber layer 2, and the teeth are formed on the surface of the tooth portion. It is constructed by covering the cloth 4.

Here, the tensile rope 1 buried in parallel in a spiral shape is made of a low elongation and high strength rope tensile material selected from polyester, aliphatic polyamide, aromatic polyamide, rayon, glass fiber, steel wire, etc. The rubber forming the extension rubber layer 2 and tooth portion 3 in which this is buried is NB (natural rubber), SBR (styrene, butadiene rubber),
CR (chloroprene rubber), NBR (nitrile rubber),
It is made of a single material such as IIR (butyl rubber), or a blend of these as appropriate, or polyurethane rubber.

On the other hand, the tooth cloth 4 is made by coating or impregnating a required knitted fabric or canvas with the elastomer material 5 mixed with short fiber powder, and a typical example is a woolly-processed crimped nylon warp and a normal nylon warp. This is a stretchable canvas with elastomer, which is made by coating or impregnating a canvas woven with nylon wefts with the elastomer material 5 mixed with the short fiber powder 6.

The tooth cloth 4 is usually attached to the surface of the toothed portion 3 of the toothed belt main body a using an adhesive to protect the surface of the toothed portion 3.

In this case, in the tooth cloth 4, the ratio of the short fiber powder 6 mixed in the elastomer material 5 to be coated or impregnated and the length of the short fiber powder 6 are selected within the above-mentioned ranges.

Next, we will discuss the results of a comparative experiment on the performance of belts by changing the ratio of short fiber powder to the elastomer material impregnated into the tooth cloth and the type of short fibers mixed in.

Experimental example 1 Glass fiber powder, carbon fiber powder, and aramid (aromatic polyamide) powder were added as short fiber powder to the elastomer material to be impregnated into the tooth cloth, and the length was 1 μ to 10 μm.
For 100 parts of the elastomer material, change up to mm.
These mixtures were each dissolved in a solvent to form a paste-like material, and this was applied or impregnated onto a tooth cloth to produce a toothed belt according to known predetermined conditions.

Next, this toothed belt was suspended between a driving pulley and a driven pulley in an atmosphere of 80°C as described above, and was run under the load conditions described above to examine the life index of the belt. The results were as shown in Figure 2.

Here, the belt life index represents the ratio of belt life.

From the results shown in Figure 2, the length of the short fiber powder is 5 μ~
It has been found that 6 mm is optimal and that it is uniformly dispersed, improving wear resistance and increasing the belt life index at the same time, but if it is 10 mm or more, the dispersion state in the elastomer becomes uneven and the reinforcing effect is significantly reduced. It was discovered.

Therefore, from a practical point of view, the length of short fiber powder is 0.5μ.
It is understood that ~10 mm is preferred.

Experimental Example 2 After adhering 10% by volume of various short fiber powders mixed into the elastomer material to the tooth cloth, the tooth cloth was dispersed between the molds during toothed belt molding, and the toothed belt was vulcanized (heated, cured). Various types of toothed belts were made by press-fitting and adhering the toothed belts to the surface of the cloth at the time of pressure (pressure), and these belts were run under the same driving conditions as in Experimental Example 1 to examine the life of the belts. The results were as shown in Figure 3.

From the results shown in Figure 3, it can be seen that toothed belts in which various short fiber powders such as carbon fiber, aramid fiber, and glass fiber are mixed in the tooth cloth have a higher belt life index than toothed belts without additives. Approved.

(Effects of the invention) As described above, the toothed belt of the present invention is made by mixing short fiber powder into the elastomer material coated or impregnated on the tooth cloth, and the abrasion resistance of the tooth surface is improved by mixing the short fiber powder. This is further improved, and when ceramic powder is mixed, the ceramic eliminates the grinding of the tooth cloth caused by roughening of the pulley surface and early breakage of the belt life, resulting in an excellent effect of increasing the belt life.

In addition, there is almost no decrease in adhesive strength due to the short fiber powder mixed in, and the strong adhesion of the tooth cloth is not inhibited in any way, and a sufficiently strong adhesive strength can be maintained.

[Brief explanation of the drawing]

Figure 1 is a partial perspective view showing an example of the toothed belt of the present invention, and Figure 2 shows toothed belts with various short fiber lengths that are press-fitted and adhered to the tooth cloth surface during belt vulcanization. FIG. 3 is a chart showing the life index of toothed belts at various times. FIG. a... Toothed belt main body, 1... Rope tensile body,
2...Extensible rubber, 3...Tooth portion, 4...Tooth cloth, 5...
...Elastomer material, 6...Short fiber powder.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. A tooth formed by embedding low elongation, high strength rope tension members in parallel in a rubber layer, and having a tooth portion, with a tooth cloth affixed to the surface thereof. A toothed belt characterized in that the tooth cloth is made of a canvas coated with an elastomer material mixed with an abrasion-resistant substance by coating or impregnation, and the surface of the tooth portions is coated with the canvas. 2 The elastomer material is CR (chloroprene rubber),
One type selected from the group consisting of NBR (nitrile rubber), H-NBR (hydrogenated nitrile rubber), CSM (chlorosulfonated polyethylene rubber), CHM (epichlorin hydrin rubber), ACM (acrylic rubber), and polyurethane. The toothed belt according to claim 1 of the above-mentioned utility model registration claim. 3. Utility model registration claim 1 or 2, in which the wear-resistant substance is at least one kind selected from the short fiber powder group consisting of glass fiber powder, glass beads, carbon fiber powder, aramid fiber powder, or a combination thereof. The toothed belt described in item 2. 4. The toothed belt according to claim 3, wherein the short fiber powder has a length of 0.5 μm to 10 mm. 5. The toothed belt according to claim 3, wherein the proportion of short fiber powder mixed is 3 to 35% by volume based on 100 parts of elastomer.