JPS62259944A - Paper skew compensating mechanism - Google Patents

Abstract

PURPOSE:To make the compensation of paper skew ever so easy, by making a conveyor roller go into reverse and moving paper backward if the paper skew is detected at the time of feeding a sheet of cut paper, and again feeding it progressively by a paper feed roller, making it collide with the conveyor roller. CONSTITUTION:A sheet of paper 1 on a hopper 2 is delivered piece by piece by a paper feed roller 3, and it is made to collide with a conveyor roller 4, making it into a curl form. then, this conveyor roller 4 is driven, feeding the paper 1 to a printing part 6. When a tilt of the paper 1 is detected to be more than the specified value by the sensor 5 installed between the conveyor roller 4 and the printing part 6, the conveyor roller 4 and the paper feed roller 3 both are reversed, feeding the paper 1 backward to the feed roller 3, and these rollers 3 and 4 are stopped. Next, the same operation as the first is carried out and, after it is repeated till the tilt of the paper 1 is set within the specified value, the paper is fed to the printing part 6. With this constitution, skewing of the paper 1 is automatically compensated, thus deterioration in quality of a printed latter of a printer is prevented from occurring.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a paper feed mechanism for a printer that uses cut paper, and more particularly to a paper skew correction mechanism.

[Conventional technology]

Most paper feeding mechanisms of conventional printers using cut paper do not have means for detecting skew feeding.

Therefore, since the paper feeding operation was completed in one pass, the paper may be printed in the printing section while being skewed and then ejected, or the paper may become jammed in the printing section, causing a shard, which may cause problems in the printing operation. It had stopped.

[Problems to be solved]

In the conventional paper feeding system, the paper feeding operation was completed in one operation, so even if skew feeding occurred, there was no means to correct it, and there was a possibility that the paper would be printed while being skewed. In addition, skew feeding has been a factor that has a negative effect on the print quality of the printer.

Solution to Problem C] In order to solve the above-mentioned conventional problems, the paper skew correction mechanism of the present invention corrects at least two left and right skews of paper in the paper feed section for printing using cut paper. means for detecting with a detector; and means for reversely rotating the shoe conveyance roller to reversely feed the paper when the skew is detected by the means;
means for correcting the skew by causing the reversely fed paper to hit the stationary transport roller again by the paper feed roller;
The apparatus is configured to include means for forwardly rotating the conveyance roller again to convey the paper toward the printing section.

〔Example〕

Next, the present invention will be specifically described with reference to the accompanying drawings.

FIG. 1 is a cross-sectional view showing an embodiment of the paper skew correction mechanism of the present invention. FIG. 2 is a top view of the embodiment of the invention shown in FIG. FIG. 3 (al~(C1) is an explanatory diagram of the operation after skew detection of the embodiment of FIG. 1 of the present invention.

First, the configuration of the paper skew correction mechanism of the present invention will be explained.

The paper skew correction mechanism of the present invention has a hopper 2 loaded with paper 1, and a zero-order paper feeder having a paper feed roller 3 that can be rotated in forward and reverse directions to sequentially feed and unload the papers in the hopper 2 one by one. A conveying roller 4 configured of a pair of upper and lower parts and capable of forward and reverse rotation is used to send the printed paper 1 to the printing unit 5, and a detection device for detecting printing skew on the paper fed by the roller 4. It is composed of two vessels.

Furthermore, the operation of the paper skew correction mechanism of the present invention will be explained.

In Fig. 1, the first paper feeding operation V'i begins by driving the paper feeding roller 3 clockwise for a certain period of time to bring the leading edge of the paper into contact with the stationary transport roller 4, causing the paper to curl as shown by the broken line. state. This is done to correct the skew feeding of the paper from side to side.

Next, the conveyance roller 4 is driven in the direction of the arrow in FIG.
Performs feeding operation to all print sections.

Therefore, the skew detector 5 provided between the conveyance roller 4 and the printing section measures the difference in detection time between the left and right sides of the paper. If the time difference is smaller than the specified value, it is determined that the paper is normal, and the paper is sent out from the conveyance roller 4 as it is, fed into the printing section, and a printing operation is performed. If the time difference is larger than the specified value, it is determined that the feed is skewed, the feeding operation is temporarily stopped, and then the operations shown in FIGS. 3(a) to 3(C) are performed. In other words, after determining that the feeding is skewed, the paper feeding roller 3 and the conveying roller 4 are moved to the position shown in FIG.
), the paper is reversely fed between the transport roller 4 and the paper feed roller 3, and then stopped. Next, in the same way as the initial paper feeding operation, the paper feed roller 3 is driven as shown in Fig. 3, and the leading edge of the paper is brought into contact with the stationary transport roller again to curl it, thereby correcting the skew of the paper. . Next, the conveyance roller 4 is driven in the direction of the arrow C1 in Figure 3 (C1), the paper is fed, and skew detection is performed again. Printing has stopped due to a feed error.

The above is a detailed description of the present invention. By adopting the present invention, it is possible to completely improve the reliability of skewing that occurs during sheet feeding.

〔Effect of the invention〕

As described above, the present invention has the effect of preventing deterioration in print quality of the printer because skew is automatically corrected.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing one embodiment of the paper skew correction mechanism of the present invention, FIG. 2 is a top view of the embodiment of FIG. 1 of the present invention, and FIG.
Figures (al to (C)) are explanatory diagrams of the operation after skew detection of the embodiment in Figure 1 of the present invention. 1... Paper 2... Hopper 3... Paper feed roller 4... Conveyance Roller 5... Oblique exhibition 6... Printing department agent Patent attorney Mura 1)
Stem Male Figure 1 Figure 2 f+ 4 Figure 3

Claims (1)

[Claims] In the paper feed section of a printer that uses cut paper, there is a means for detecting skew feeding of paper on the left and right sides when paper is fed, and a means for detecting skew feeding on the left and right sides of the paper when paper is fed, and a means for detecting skew feeding on the left and right sides of the paper when the paper is fed, and a paper conveying roller when the skew feeding is detected by the means. means for rotating the paper in the reverse direction and feeding the paper in the reverse direction;
Means for correcting the skew by causing the reversely fed paper to hit the stationary conveyance roller again by the paper feed roller, and means for rotating the conveyance roller in the forward direction again to convey the paper toward the printing section. A paper skew correction mechanism characterized by comprising: