JPS58183276A - Preparation of platen roller - Google Patents

Abstract

PURPOSE:To prevent the slip between a platen roller and printing paper, by planting brushes comprising a material having hardness higher than that of the material of the platen roller to the inner peripheral surface of a cylinder and the platen roller is passed through the cylinder to form a number of recessed and protruded stripes along the axial direction to the peripheral surface of the platen roller. CONSTITUTION:A plurality of brushes 22 made of a metal or synthetic resin having hardness higher than that of the material of a platen roller 21 are planted to the inner peripheral surface of a cylinder 20 having an inner diameter larger than the diameter of the platen roller 21. In this state, when the platen roller 21 is passed through the cylinder 20, a number of recessed and protruded stripes 23 along the axial direction are formed on the surface of the platen roller 21 by the brushes 22.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a platen roller, and more particularly to a method of manufacturing a platen roller that is used in typewriters and the like and also serves as a paper feeder.

Recently, typewriters have become more sophisticated, and can store printed characters electronically.Furthermore, by rotating the platen in the opposite direction, characters printed a few lines ago can be corrected using correction ribbon tape. I can do it. Accordingly, C2 is required to have an extremely high precision structure because the platen is rotated in the opposite direction to reposition the same type at the location where it has already been printed on the paper.

Such a high-precision structure can be roughly divided into the vertical feeding direction of the printing paper and the horizontal feeding direction of the carriage, but in the case of the vertical feeding direction, in addition to the accuracy of the feeding mechanism, the precision of the platen roller and the printing paper is also important. Misalignment due to slip between the parts has also become an extremely important factor in the quality of correction.

In general, typewriters and other devices feed paper using frictional force based on the coefficient of friction between the platen surface and the paper, but in order to feed paper without slipping, it is necessary to increase the friction coefficient of the platen. good.

There are two methods for increasing the coefficient of friction: using a material with a high coefficient of friction and increasing the surface roughness.

When considering how to make a material with a high coefficient of friction for the rubber that makes up the platen roller, in general, rubber with low hardness has a higher rubber content and a higher coefficient of friction. However, the hardness of the platen rubber has a large effect on printing quality in the case of impact printing. That is, if the hardness decreases, the ink transferability from the ink ribbon deteriorates, and the printed characters sink into the ink, making the periphery of the printed characters blurry and lack of sharpness. Therefore, in order to increase the friction coefficient of the platen without degrading the print quality, it is desirable to increase the surface roughness.

A conventional paper feeding device using a platen roller has a structure as shown in FIGS. 1 and 2, for example. That is, what is indicated by the reference numeral 1 in the figure is a platen roller;
A pulley 2 is fixed to one end of the rotating shaft 1a,
The other end of the belt 3, which is placed on the pulley 2, is placed on a pulley 5 fixed to the output shaft of a paper feeding motor 4, and transmits rotational force. The printing paper 6 attached to and guided by the platen roller 1 is attached to the tips of the left and right arms 7a, 7a,
A roller (paper pail roller) rotatably supported on a shaft 7b horizontally suspended between the rollers? ,L! : The printing paper 6 is pressed against the platen 1 by the feed rollers 8 and 9, and is fed by the palm friction force generated by the pressing force of these rollers and the platen roller 1.

With this structure, the platen roller 1 starts to rotate due to the rotation of the motor 4, and when it starts rotating in the direction of arrow B, the printing paper 6 and the platen roller are moved in accordance with the pressing force of the rollers 7, 8, 9 against the platen. The printing paper 6 tends to move in the direction of arrow C along the platen roller 1 due to the frictional force generated by the friction coefficient μm between the printing paper 6 and the platen roller 1. And further printing paper 6
The rollers 7 to 9 are rotated in the direction of the arrow by the frictional force generated by the friction coefficient μ2 between the rollers 7, 8 and 9.

On the other hand, there is a rotational load on the bearing portion of each roller (not shown), and this rotational load acts as a force that pulls the printing paper 6 back in the direction of arrow E. That is, the rotational load of each of the rollers 7 to 9 generates a moving load of the printing paper based on the friction coefficient μ2 and the pressing force of the rollers. This load causes slippage between the printing paper 6 and the platen roller 1.

Therefore, in an attempt to increase the frictional force by roughening the surface of the platen roller 1, platen rollers have conventionally been manufactured by the method shown in FIG. 3.

That is, the material 12 of the platen roller is rotated in the direction of the arrow 1 mm, and the rotation A o is rotated in the opposite direction of the arrow 11 to bring them into contact, and at the same time, the material 12 of the platen roller is moved in the direction of the arrow F, which is the axial direction, for polishing. In this way, the whetstone 10
The surface roughness of the material 12 becomes rougher depending on the surface roughness of the material 12.

However, numerous streaks 14 on the material 12 obtained in this manner are formed in the direction of rotation of the platen roller. In other words, it is not very useful in preventing slippage of the printing paper because it occurs in the direction of movement of the printing paper.

The present invention was made in view of the above circumstances, and an object of the present invention is to provide a method of manufacturing a platen roller that can extremely easily increase the surface roughness.

In the present invention, in order to achieve the above object, brushes harder than the material of the platen roller are implanted at a predetermined density on the inner circumferential surface of the cylindrical body.

A method was adopted in which the platen roller was moved in the longitudinal direction while in contact with the bristles, thereby forming numerous slits along the longitudinal direction of the platen roller, thereby forming rod uneven stripes.

Hereinafter, details of the method of the present invention will be explained with reference to the drawings.

4 and 5 illustrate the method of the present invention and the platen roller obtained by the method. In the figures, the reference numeral 20 is a cylinder, and 2°0 of this cylinder is the platen roller 2.
The platen roller 21 has an inner diameter larger than the diameter of the platen roller 21, and a countless number of brushes 22, which are harder than the material of the platen roller 21, are flocked centripetally on its inner peripheral surface. The brush 22 may be made of metal wire, synthetic resin, etc., for example. If the platen roller 21 is passed through the cylindrical body 20 having such a structure, the brush 22 will form countless uneven lines 23 along the axial direction on the surface of the platen roller 21. The surface roughness of the platen roller 21 can be freely controlled by changing the hardness of the brush 22 and the density of the flocked hair.

In this way, it is possible to obtain a platen roller that has a large surface roughness, a large coefficient of friction, and does not cause slippage between the platen roller and the printing paper.

As is clear from the above description, according to the present invention, a countless number of brushes that are harder than the material of the platen roller are implanted on the inner peripheral surface of the cylinder, the platen roller is passed through the cylinder, and the platen roller is Since a method is used to form countless uneven stripes along the axial direction on the top, the uneven stripes are formed perpendicular to the feeding direction of the printing paper, and there is no slippage between the paper and the printing paper. A platen roller with good printing quality can be obtained.

[Brief explanation of drawings]

1 and 2 are a perspective view and a side view of the main parts of a printing device equipped with a platen roller to which the present invention is applied, FIG. 3 is a perspective view illustrating the conventional method, and FIG. 4 is a method of the present invention. FIG. 5 is a perspective view of a platen roller obtained by the method of the present invention.

Claims (1)

[Claims] A brush whose hardness is 11 degrees harder than the material of the platen roller is implanted on the inner circumferential surface of the cylindrical body. A method for manufacturing a platen roller, characterized in that a concavo-convex strip is formed in the axial direction on a surface of the platen roller.