JPH0111478Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a special paper feeding tractor belt for printing devices used in computers and printers.

Conventionally, sprocket wheels or chains with pins have been used to feed paper, but these have the drawbacks of slack in the paper and misalignment of the first and second sheets of paper, which is also fatal to office machines. However, there was a problem with the generation of noise, which is a major drawback. Therefore,
Recently, some paper feeding tractor belts have been put into practical use, as shown in Japanese Utility Model Publication No. 42-14208, in which protrusions are integrated into the surface (back side) of the toothed belt. are made of the same hardness, so if the entire belt has high hardness, the wear resistance of the protrusions is good, but the belt is too rigid and there is a problem with flexibility, and conversely, if the entire belt has low hardness, In this case, the flexibility was good, but the problem was that the protrusions were subject to severe wear.

The present invention aims to address and improve the above-mentioned problems by improving the flexibility of the belt and improving the abrasion resistance of the protrusions by devising the structure of the belt surface. This is the purpose.

In other words, the feature of the present invention is that among polyurethane belts having a plurality of protrusions on the surface of the toothed belt body, the protrusions and a part of the belt surface (back surface) have normal hardness over the required thickness. The reason is that the other parts of the belt are made harder than the back surface of the belt under the tensile member and the teeth.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The paper feeding tractor belt according to the present invention will be explained below with reference to the accompanying drawings.

FIG. 1 is a partial cross-sectional perspective view of a paper feeding tractor belt according to the present invention, in which a is the main body of the paper feeding tractor belt, 1 is glass fiber,
Low elongation, high tensile strength rope tensile materials such as stranded ropes made of polyester, aliphatic polyamide, aromatic polyamide, etc. or steel wires are buried in parallel along the longitudinal direction in the tensile section 2 made of polyurethane elastic material. A toothed part 3 made of the same material is integrated with the tension part 2 on the lower surface of the tension part 2, and a conical protrusion 4 made of polyurethane is integrated with the surface of the tension part 2, that is, the back surface of the belt. It is set up as a standard.

However, this paper feeding tractor belt a
As shown in Fig. 2, the thickness H of the thin surface portion of the protruding portion 4 and the belt tension portion 2 is 90° (JIS-A hardness).
On the other hand, the back side of the lower surface of the tensile member 1 of the belt tensioning portion 2 and the toothed portion 3 are made of polyurethane with a low hardness of about 80°, which is lower than the projection portion 4. Here, the thickness H of the surface part of the belt tensioning part 2 is usually 0.5 mm or less, and if it becomes 0.5 mm or more, the high hardness urethane rubber layer becomes too thick and the rigidity increases, causing the problem of decreasing the flexibility. Therefore, the thickness H of the surface part needs to be 0.5 mm or less.
In addition, the protrusion 4 is usually made of a high hardness rubber layer of about 90 degrees, but by mixing a lubricant such as graphite, Teflon, or molybdenum disulfide powder into this, the wear resistance can be improved. Together with the protrusion 4
It is also possible to lower the coefficient of friction of the paper and improve the slippage of the paper.

As described above, the paper feeding tractor belt of the present invention has a plurality of protrusions provided at a constant pitch on the surface of the polyurethane toothed belt body. It has excellent abrasion resistance because the protrusions are particularly hard, and when a large number of sheets of paper are being fed, it has excellent abrasion resistance and prevents the early damage noise of the protrusions. This invention has the advantage of eliminating slack in the belt and stabilizing smooth paper feeding, but this invention also makes a part of the belt surface hard, and the back surface of the belt and the teeth are made of a urethane rubber layer with a lower hardness than that of the belt. This belt has features such as low rigidity, improved flexibility, and ability to reduce torque when driving the belt, making it a particularly suitable belt for use as a tractor belt for paper feeding in office equipment.

[Brief explanation of the drawing]

FIG. 1 is a partial cross-sectional perspective view of a paper feeding tractor belt according to the present invention, and FIG. 2 is a partial side cross-sectional view of the same belt. a... Belt body, 1... Rope tensile body, 2...
... tension part, 3 ... tooth-shaped part, 4 ... conical projection.

Claims (1)

[Claims for Utility Model Registration] 1. A belt in which a plurality of protrusions are provided at a constant pitch on the surface of a polyurethane toothed belt body,
A tractor belt for paper feeding, characterized in that each protrusion and a part of the belt surface are made harder than other parts of the belt. 2. The paper feeding tractor belt according to claim 1, wherein the hardened belt surface has a thickness of 0.5 mm or less on the belt surface side. 3. The paper feeding tractor belt according to claim 1 or 2, wherein the hard part of the belt has a hardness of 90° or more, and the other parts have a hardness of around 80°.