JPH0533799Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a flat belt, and more particularly to a flat belt for precision high-speed transmission.

[Conventional technology]

Conventionally, as shown in Figure 5A, flat power transmission belts are made by integrally laminating a tension layer A made of synthetic fibers with a woven fabric B on one side and a rubber sheet C on the other side. is publicly known.

[Problems with conventional technology]

However, the flat belt with the above structure has a woven fabric B
Due to the difference in shrinkage rate between the rubber sheet C and the rubber sheet C, the belt bends in the width direction as shown in FIG.

In particular, in the case of flat belts for precision high-speed transmission, the contact pressure of the belt surface in contact with the pulleys (not shown) is not uniform in the width direction, resulting in irregular slips caused by load fluctuations, etc. There were drawbacks that hindered the

[Problems solved by invention]

This invention was made in consideration of the above problems, with the object of providing a flat belt which substantially eliminates the difference in shrinkage rate between the woven fabric layer and the rubber sheet layer which sandwich the tension layer, and which can always maintain a flat state without warping in the width direction.

[Technology to solve problems]

That is, the flat belt of this invention has a rubber-like elastic layer in which a tension layer is embedded.
The rubber-like elastic layer is characterized in that short inorganic fibers having a length of 1 mm or less are uniformly mixed with the main orientation direction of the fibers being in the belt width direction.

〔Example〕

Next, this invention will be explained using examples.

FIG. 1 is a cutaway perspective view of essential parts of an embodiment of this invention.

The flat belt 1 of this invention has a rubber-like elastic layer 3 embedded with a tension layer 2 made of a synthetic fiber with no elongation and excellent tensile strength, such as polyester or polyaramid.
In the rubber-like elastic layer 3, inorganic short fibers 4...4 having a length of 1 mm or less are uniformly mixed with the main arrangement direction (arrow M) of the fibers 4...4 being the belt width direction. There is. In the figure, 5 is a woven fabric layer provided on the other side of the tension layer 2.

In addition, as the above-mentioned example, inorganic short fiber 4...
As 4, glass fiber or ceramic fiber is preferably used.

The short fibers 4...4 preferably have a thickness of 10 to 30 microns and an aspect ratio of 50 or less.

In this invention, the length of the short fibers is set to 1 mm or less in order to orient the short fibers 4 in the thickness direction of the rubber-like elastic layer 3, which is shown enlarged in Fig. 2. As shown, on the surface of the rubber-like elastic body 3,
This is to cause some portions 4' of the fibers 4 .

Therefore, if the length of the short fibers is longer than 1 mm, the above-mentioned protrusion will decrease, and an increase in the coefficient of friction cannot be expected so much, which is inappropriate.

In the above embodiment, a rubber-like elastic layer 3 is provided on one side with a tension layer 2 in between, and a woven fabric layer 5 is provided on the other side, but as shown in FIG.
... 4 may be arranged and mixed in the width direction as rubber-like elastic layers 3, 3, or as shown in FIG. 4, the rubber-like elastic layer 3 may be provided only on one side.

[Effect]

In the flat belt of this invention, the short fibers 4...4 are mixed in the rubber-like elastic layer 3 in a manner arranged in the belt width direction. By reinforcing the short fibers in the width direction, mutual shrinkage rates are made uniform, and warpage of the belt caused by these differences is effectively prevented. Also, the fourth
As shown in Fig. 5, even if the belt is flat without the woven fabric layer 5, the belt is reinforced in the width direction by the short fibers 4...4, so the crown usually provided on the pulley (not shown) Also, warpage in the width direction of the belt caused by initial tension is also prevented.

Furthermore, since some of the short fibers protrude above the surface of the rubber-like elastic body, they can be caught on the surface, increasing the coefficient of friction and preventing slippage.

〔effect〕

Since this invention is constructed as described above, warping in the width direction can be eliminated even if the flat belt is made by integrally laminating a woven fabric layer and a rubber-like elastic layer with a tension layer in between. The contact condition with the pulleys in the belt width direction can be made uniform, and the short fibers that partially protrude on the surface of the rubber-like elastic layer increase the friction coefficient of contact with the pulleys, reducing irregular slips. This prevents this from occurring and enables precise, high-speed transmission.

[Brief explanation of drawings]

FIG. 1 is a cutaway perspective view of the main parts of an embodiment of this invention.
Figure 2 is an enlarged sectional view of the main parts of the embodiment, Figures 3 and 4.
The figure is a sectional view of another embodiment, and FIGS. 5A and 5B are explanatory views of the conventional example.

Claims (1)

[Claims for Utility Model Registration] (1) In a flat belt having a rubber-like elastic layer in which a tension layer is embedded, the rubber-like elastic layer includes:
1. A flat belt comprising inorganic short fibers having a length of 1 mm or less mixed uniformly with the main orientation direction of the fibers being in the width direction of the belt. (2) The flat belt according to claim 1, wherein the inorganic short fibers are glass fibers or ceramic fibers.