Patent Application
20070057431
The present invention relates to a roller with surface friction, and more particularly to a roller having a coarsened layer and a finished layer formed on an outer circumferential surface thereof, and a plurality of micro sharp points formed on the finished layer to produce high surface friction on the roller.
A roller is an important element frequently used in different machines to push feed sheet material. For example, a roller is frequently used in a printer, a photocopier, and many other office machines to roll on a top of a stack of sheet paper, so as to push and feed the sheet paper at the highest position of the stack.
Most of the conventional rollers are produced to have a smooth outer circumferential surface that provides insufficient frictional force in push feeding the sheet material and results in idling of the roller. One of the conventional ways to solve this problem is to form patterns on the roller by engraving the outer circumferential surface of the roller. This solution is highly labor and time consuming, particularly for a metal roller.
Another conventional solution is to put a soft rubber sleeve over the circumferential surface of the roller, in order to increase the frictional force of the roller. However, the putting of the rubber sleeve over the roller increases not only the manufacturing cost but also the manufacturing process of the roller. Moreover, the rubber sleeve has low thermal plasticity and durability, and tends to become worn out or hardened after being used over a prolonged time, preventing the roller from stably push feeding the sheet material.
It is therefore tried by the inventor to develop a roller with surface friction to eliminate the drawbacks existed in the conventional rollers.
A primary object of the present invention is to provide a roller with surface friction, so that the roller is suitable for push feeding sheet material.
To achieve the above and other objects, the roller with surface friction according to the present invention includes a coarsened layer and a finished layer formed on an outer circumferential surface of the roller from inner to outer side. The coarsened layer is formed by way of subjecting the roller to coarsening, and the finished layer is formed by way of subjecting the roller to a predetermined surface finishing. And, a plurality of micro sharp points are formed on the finished layer to give the roller with high surface friction, so that the roller is suitable for push feeding sheet material.
The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein
Please refer to FIGS. 1 to 3, in which a roller 10 according to the present invention is shown. As shown, the roller 10 includes a coarsened layer 11 and a finished layer 12 sequentially formed on an outer circumferential surface of the roller 10 from inner to outer side. The coarsened layer 11 is formed by way of subjecting the outer circumferential surface of the roller 10 to coarsening. The finished layer 12 is formed on the coarsened layer 11 by way of subjecting the coarsened layer 11 of the roller 10 to a predetermined surface finishing, such as metal plating, metal spraying, etc., so as to form a metal layer on the coarsened layer 11. As can be clearly seen from
The micro sharp points 13 are formed on the finished layer 12 by way of etching, engraving, pressing or scooping, and have a size about 40μ to 100μ each. The micro sharp points 13 so formed produce a gripping force to grip a sheet material without the risk of piercing through the sheet material, and therefore enable the roller 10 to serve as a roller suitable for push feeding sheet material.
The present invention has been described with a preferred embodiment thereof and it is understood that many changes and modifications in the described embodiment can be carried out without departing from the scope and the spirit of the invention that is intended to be limited only by the appended claims.
