JPH0449072A - Paper feed apparatus of printer - Google Patents

Abstract

PURPOSE:To prevent the shift of a printing position, in a printer having a paper feed mechanism, by using a means detecting the feed shift of printing paper and a mechanism correcting the feed shift. CONSTITUTION:Paper feed rollers 8 respectively driven independently are arranged at left and right positions with respect to a paper feed direction. These left and right rollers are usually rotated in the same direction to carry out paper feed in a pair but, when correction is performed, the left and right rollers are independently rotated. Rollers 6 for feed quantity sensors are arranged so as to come to the left and right single ends of printing paper and left and right feed quantity sensors 7, 11 detect the left and right feed quantities of the printing paper by rotating the rollers 6. When the shift of feed quantities is generated by the bending of the printing paper or the slip of the paper feed rollers 8, the signals from the left and right feed quantity detection sensors 7, 11 are compared with the signal of a feed quantity timing generating circuit to judge said shift and left and right motors 9, 13 are driven.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a paper feeding device for a printing machine.

[Summary of the invention]

This invention improves the printed value by using a means for detecting paper feeding deviation of printing paper and a mechanism for correcting paper feeding deviation in a printing machine having a paper feeding mechanism. The purpose is to prevent misalignment.

[Conventional technology]

Conventionally, paper feeding devices have had a feeding mechanism only in the paper feeding direction when feeding printing paper to a printing machine.

[Problem to be solved by the invention]

However, with conventional paper feeding mechanisms, the only way to prevent printing paper from shifting is to place it on the left and right! This is done only by using a guide plate, and if the printing paper is fed in a tilted manner due to bending or the like, there is no mechanism to correct this, so there is a problem that the printing position will shift.

In order to solve these conventional problems, it is an object of the present invention to prevent paper feeding deviation of printing paper and to perform printing at an accurate paper position.

[Means to solve the problem]

In order to solve the above-mentioned problems, the present invention provides a printing machine having a paper feeding mechanism, which comprises means for detecting paper feeding deviation of printing paper and means for correcting paper feeding deviation.

[Effect]

In a printing machine configured as described above, when printing paper is fed at an angle to the paper feeding direction due to bending or roller slippage, sensors placed on the left and right sides determine the amount to be fed and the actual amount to be fed. Detects the difference in feed amount,
Independent paper feed rollers placed on the left and right perform differential correction bone feeding.

As a result, the printing paper is always fed perpendicular to the paper feeding direction.

(Example〕 Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a schematic structural explanatory diagram showing an embodiment of the invention. As shown in the figure, paper feed rollers 8 are arranged to be driven independently on the left and right sides with respect to the paper feed direction. Normally, these rollers rotate in the same way on the left and right sides, and paper is fed in pairs, but when correction is performed, the left and right sides rotate independently. Feed amount sensor roller 6
are arranged so as to be located at one end of the left and right sides of the printing paper, and as this rotates, the left and right feed amount sensor 7.11 detects the left and right feed amount.

FIG. 2 is a block diagram of the paper feeding device of the present invention.

Signals from the left and right feed amount sensors 7.11 are converted into digital signals by the A/D converter 15 and sent to the CPU 16. Usually, the CPU 16 determines the feed amount only based on the signal from the feed amount timing generation circuit 14 and sends a motor drive signal to the motor controller 17. If a deviation occurs, this is determined by comparing the signal from the left and right feed amount detection sensors 7.11 with the signal from the feed amount timing generation circuit 14, and the deviation in the left and right feed amounts is determined. A motor drive signal including the correction value is sent to the motor controller 17, and the left and right motors 9, 13 are driven.

〔Effect of the invention〕

As explained above, in a printing machine having a paper feeding mechanism, the present invention enables stable paper feeding by using means for detecting paper feeding deviation of printing paper and means for correcting paper feeding deviation, This has the effect that printing is always performed at the correct paper position.

[Brief explanation of drawings]

The figure shows an embodiment of a paper feeding device of a printing machine according to the present invention,
FIG. 1 is a schematic configuration diagram, and FIG. 2 is a block diagram. 1 ・ ・ 4 ・ ・ 6 ・ ・ 7.11. Roller left/right feed Motor feed amount timing generation circuit A/D converter CPU Motor controller

Claims (1)

[Claims] 1. A paper feeding device for a printing machine having a paper feeding mechanism, characterized in that the printing machine has means for detecting paper feeding misalignment of printing paper, and means for correcting paper feeding misalignment.