CS242415B1 - Device for precise feed of non-perforated paper - Google Patents

Abstract

The purpose of the invention is to ensure accurate movement of non-perforated paper during repeated back and forth movement. This purpose is achieved by a device having pairs of wheels, each of which consists of a drive and a pressure wheel, where the drive wheels are formed of non-yielding corundum or diamond grinding wheels. These drive wheels are coaxial, the movement of the paper is accurate over a wide range of pressure forces and various types of paper, while this paper is not damaged. The device is particularly suitable for IY recorders, but it can also be used for printers, registration devices, etc.

Description

(54)

Device for precise feeding of perforated paper

The purpose of the invention is to ensure accurate displacement of the unperforated paper with repeated movement back and forth.

This is achieved by a device having pairs of wheels, of which each consists of a drive and a pressure wheel, wherein the drive wheels consist of rigid corundum or diamond grinding wheels. These drive wheels are coaxial, the movement of the paper is accurate over a wide range of pressing force, and various types of paper, while the paper is undamaged. The device is particularly suitable for IY recorders, but can also be used for printers, recording machines, etc.

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242 415

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BACKGROUND OF THE INVENTION The present invention relates to an apparatus for accurately feeding unperforated paper, e.g.

The hitherto known devices consist of pairs of wheels, each with one drive and one pressure roller. These devices use rubber driving wheels or made by special technological processes. The rubber wheels are inexpensive and show very good adhesion to the paper, but they are not able to ensure accurate paper feed when repeating back and forth. Production of drive wheels from special materials resp. with special surface treatment is expensive and additionally protected by patents.

Also known are the devices used, for example, in copiers where an aluminum alloy roller, roughened by sandblasting and subsequent electrolytic etching, is used to feed the unperforated paper at a constant speed. The paper is pressed by a stationary sheet of Teflon. The disadvantage of this device is, on the one hand, the sophisticated technology of the roll production, the necessity of occasional cleaning of the device due to the low grain size of the roll surface and greater resistance of the moving paper when pressed by the stationary sheet of teflon.

The aforementioned drawbacks are overcome by the device for precisely feeding the perforated paper according to the invention. In essence, the device formed by the pairs of the drive and thrust wheels, where the drive wheels are coaxial, the drive wheels are formed by rigid corundum or diamond grinding wheels.

The device according to the invention ensures the exact movement of the unperforated paper over a wide range of pressing force exerted on the pressure rollers for a wide range of types of paper used. There is no damage to the paper feed, and the machine allows high feed accuracy to be maintained while significantly reducing production costs.

One example of the arrangement of the device according to the invention is shown schematically in the attached drawing. This exemplary embodiment is designed for a simple and inexpensive XY recorder. The device is shown in the drawing in a front view in the direction of movement of the paper being fed.

In this case, the apparatus consists of two pairs of wheels, each pair consisting of one drive wheel 1 and one pressure roller 2 and a base plate 2 for laying unperforated paper. The drive wheels 1 are coaxial and consist of CARBORUNDUM ELECTRITE grinding wheels type A99B and machined to exactly the same diameter. The drive wheels 1 are mounted on a common shaft 7, which is rotatably mounted on the ends 4 at both ends. The pressure wheels 2 are made of Teflon and have a conical shape. They can also be made of other compliant materials. These pressure wheels 2 are located on the movable pressure arm 2 each against the drive wheel 1.

The device for precisely feeding the non-perforated paper operates by placing the perforated paper 6 on the base plate 2d @ of the desired initial position with the pressure arms 2 raised. After its adjustment, the pressure arms 2 are folded to the working position, where the paper 6 is firmly gripped between the drive wheels 1 and the pressure wheels 2. The movement of the paper 6 is effected by rotating the drive wheels 1, which can be secured in various ways, for example by a stepper.

The device according to the invention can be used in particular in the implementation of XY recorders, possibly for printers, recording devices and the like.

Claims (1)

SUBJECT OF THE INVENTION 242 415 Apparatus for accurately feeding unperforated paper, for example, for recorders, printers, and recorders, comprising pairs of drive and thrust wheels, wherein the drive wheels are coaxial, characterized in that the drive wheels (1) consist of rigid corundum or diamond grinding wheels.