JPS6315629Y2 - - Google Patents

Description

[Detailed explanation of the invention] This invention relates to a low edge type V-belt.
This relates to belt improvements.

In general, low-edge type V-belts have the advantage of having a high friction coefficient on the side surfaces and being easy to manufacture, but when it comes to high rotation and high torque transmission, the apparent friction coefficient when using the V-belt and the above-mentioned side friction coefficient There was a problem that the noise was more likely to be generated due to the synergistic effects of the noise.

Conventionally, in order to solve this problem, as seen in Japanese Patent Publication No. 55-41910, Japanese Patent Publication No. 54-36630, and even Japanese Patent Application Laid-Open No. 54-31849, efforts were made to reduce the surface frictional resistance of the side surface of the V-belt. However, as the effect disappears when the side surface layer wears out due to contact with the pulley, there is a problem in the sustainability of the effect.
As seen in No. 95661, it has been proposed to adjust the apparent coefficient of friction by making the belt cross section into a two-step angle, but it is technically difficult to form a two-step angle, and the compression part In order to compensate for the reduction in lateral pressure, it was necessary to use high-quality materials, which caused problems such as poor versatility. It has also been proposed to add cogs or unequal pitch unevenness to the inner and outer peripheral surfaces of the V-belt to improve the flexibility of wrapping around the pulleys and to adjust the lateral pressure at the same time. Further, when cutting and forming the cog etc., the work process becomes complicated, and in any case, there is a drawback that manufacturing equipment or labor is required.

In view of the various problems mentioned above, this idea was developed to create a low-edge type V that generates less noise and is easy to manufacture.
This is a low-edge type V-belt that is made for the purpose of providing a belt, in which the entire compressed part inside the tensile strength member is made of a fiber-reinforced rubber-like elastic body, and the compressed part is made of a fiber-reinforced rubber-like elastic body. It is characterized in that a large number of rod-like bodies made of a soft rubber-like elastic body and having variable cross-sectional areas are inserted through and integrated into the compression part in a non-uniform arrangement in the width direction of the compression part.

Next, this invention will be explained using examples.

FIG. 1 is a side view of an embodiment of this invention, and FIG. 2 is a sectional view taken along the line -- in FIG.

The low edge type V-belt (hereinafter referred to as V-belt) 1 of this invention has a compression section 3 located inside the tensile strength member 2.
The entire body is made of a rubber-like elastic body 4 such as rubber kneaded with short fibers, such as stiffflex rubber, and the compressed portion 3 is made of a rubber-like elastic body 4 that is softer than the rubber-like elastic body 4. A large number of rod-shaped bodies 6 having an irregular cross-sectional area 5 are inserted through the compressed portion 3 in a non-uniform arrangement in the width direction (arrow P) and are integrated.

In the above embodiment, the hardness of the rubber-like elastic body 4 constituting the compression section 3 is JIS A78° to 84° in the case of stiff flexible rubber, and the hardness of the rod-shaped body 6 is JIS A60° to 70°. It is said to be ゜.

Next, the means for manufacturing the V-belt of this invention will be explained.

First, short fibers of cotton, nylon, Kevlar, or polyester are kneaded into a chloroprene rubber base using a known method, and a sheet is formed using a calendar roll. Cut this sheet to a certain width, twist it 90 degrees and join it. Next, this sheet 7
As shown in Figure 3, cut into appropriate lengths l ₁ , l ₂ ...,
As shown in FIG. 4, a strip 8 cut out from a separately prepared soft rubber sheet is inserted between the cut pieces 7'.
Join the joint ends.

Next, the rubber sheet thus obtained is placed in the compression section of the V-belt, and thereafter the V-belt is compressed by normal means.
It forms the belt.

The compression section 3 of the V-belt 1 of this invention has high elasticity in the lateral direction due to the integrated soft rubber-like elastic material that is inserted through the V-belt 1 at random, so the surface friction of the compression section is lower than that of the conventional low edge type. Although it is the same as a V-belt, it generates less noise because it absorbs lateral pressure due to its elasticity. In addition, the noise of the belt becomes large at the resonance point between the pulley and the belt, but the natural frequency of the V-belt 1 is substantially indeterminate due to the shape and arrangement of the compression part and the soft rubber-like elastic material that penetrates in the lateral direction at random. Therefore, even if the natural frequency of the pulley side is constant, resonance phenomenon is less likely to occur.
Noise generation is also reduced.

Incidentally, when the relationship between the ratio of soft rubber in the stiffness of the compression section of the V-belt 1 and noise and the relationship between rubber hardness and life ratio were tested using the test equipment shown in Figure 5, the results shown in Figures 6 and 6 were tested. The results shown in Figure 7 were obtained.

The test device in FIG. 5 includes a drive pulley 10,
Consists of a driven pulley 11 and an idler 12,
A V-belt 1 is wound between these, and a microphone 13 is placed in the center to measure the noise.The diameter of the drive and driven pulleys is each 120.7φ, the idler is 63.5φ, the rotation speed of the drive pulley is 4900rpm, A load of 120 pounds is applied to the idler in the direction of the arrow.

Figure 6 shows the correlation between the ratio of soft rubber in the stiffness of the compression section and the noise (dBA).
It has been found that good results are obtained when the ratio is between 20 and 40%. The belt used was made of three randomly placed layers of soft rubber having a hardness of 65°, a thickness of 1.2 m/m, and a width of 5 to 15 m/m.

Figure 7 shows the correlation between the hardness of soft rubber and the life of the belt.
The case where various soft rubbers are randomly filled is shown for the 80° one. The belt used has a soft rubber ratio of 30%, a thickness of 1.2m/m, and a width of 1.2m/m.
Three layers of 5m/m to 15m/m were used at random. According to the results, it was found that soft rubber hardness of around 60° to 70° is good, and this range is the most desirable in terms of correlation with life ratio.

As mentioned above, the V-belt 1 of this invention is
It has various practical effects, such as being less likely to generate noise even when the V-belt is idling and under high load and high rotation conditions, and being easy to manufacture since it can be manufactured using almost any conventional technology.

[Brief explanation of drawings]

Fig. 1 is a side view of an embodiment of this invention, Fig. 2 is a sectional view taken along the line - - of Fig. 1, Figs. 3 and 4 are explanatory diagrams of the manufacturing state of the embodiment, and Fig. 5 is a concept of the test device. 6 and 7 are graphs showing the test results. DESCRIPTION OF SYMBOLS 1... Low edge type V belt, 2... Tensile strength body, 3... Compression part, 4... Rubber-like elastic body, 5...
Cross section, 6... Soft rubber-like elastic body.

Claims (1)

[Scope of utility model registration request] In a low edge type V-belt, the entire compression section inside the tensile strength member is made of a fiber-reinforced rubber-like elastic material, and the cross-sectional area is constant. 1. A low edge type V-belt, characterized in that a large number of rod-shaped bodies are inserted through and integrated into the compression part in a non-uniform arrangement in the width direction of the compression part.