JPH02136264A - Paper feed mechanism of printer device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Summary] To enable stable paper feeding by preventing misalignment between layers that occurs during feeding when multiple sheets of copy paper are stacked for printing, regarding a paper feeding mechanism of a printer device. A mechanism for transporting the paper by engaging with a paper feed hole, a platen, and a pair of pinch rollers are arranged in a 111q order, and the continuous paper is pushed by the paper transport mechanism. In the paper feeding mechanism that pinches and transports the paper with pinch rollers after printing on the platen, rotational driving force is applied to both of the pair of pinch rollers, and the feed amount of the roller on the platen side is adjusted to the side opposite to the platen. The feed amount is set to be larger than the feed amount of the roller.

[Industrial application field]

The present invention relates to a paper feeding mechanism of a printer device.

[Conventional technology]

The paper feeding mechanism of a conventional printer device is shown in Fig. 3 (a).
), the platen 2 includes a sprocket 1, a platen 2, and a pail roller 3 pressed against the platen, and overfeeds the continuous paper 4 sent out from the sprocket 1 relative to the sprocket 1. There are also those that are conveyed by being pinched with a pail roller 3, and those that are equipped with a sprocket 1, a platen 2, and a pair of pinch rollers 5 and 6, as shown in FIG. A device is used in which the book paper 4 is held and conveyed by two pinch rollers 5 and 6 that are driven to overfeed the sprocket 1.

[Problem to be solved by the invention]

In the above-mentioned conventional paper feeding mechanism, when paper is fed when printing multiple sheets of copy paper one on top of the other, the upper layer paper 4' is in front of the lower layer paper 4# with respect to the platen 2, as shown in Fig. 4. will occur. This especially occurs when the holding force between sheets is weak, such as when multiple sheets of paper are stapled together.

This misalignment between the paper sheets also causes interlayer misalignment on the printing surface, which is undesirable as the printing position shifts.Also, if the interlayer misalignment progresses further, the sprocket pin and the hole in the paper will not fit properly. This can cause problems such as the paper coming off the pins and causing a jam.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, it is an object of the present invention to provide a paper feeding mechanism for a printer device that prevents misalignment between layers that occurs during paper feeding and enables stable paper feeding.

[Means to solve the problem]

FIG. 1 is a diagram explaining the principle of the present invention.

In the figure, 1 is a sprocket that engages with a paper feed hole to transport the paper, 2 is a platen, 5 and 6 are pinch rollers, and 7 is a print head, which is conveyed by the sprocket 1. After printing is performed on the paper 4 by the print head 7 on the platen 2, the paper 4 is discharged in the direction of arrow P by the rotational force of a pair of pinch rollers 5.6 located above the platen 2. At this time, if the paper feed amounts of the sprocket 1, the pinch roller 5 on the platen side, the pinch roller 6 on the opposite side are c, a, and b, respectively, (
Set <baa.

[For production]

For the feed itc of sprocket 1, pinch roller 5.
By increasing the feeds ia and b of 6, the slack in the paper between sprocket 1 and pinch rollers 5 and 6 is eliminated.
Furthermore, by making the feed amount of the pinch roller 6 on the opposite side of the platen smaller than the feed amount FJa of the pinch roller 5 on the platen side, it is possible to prevent the paper on the outside of the platen 2 from leading the paper on the inside. be able to.

[Example] FIG. 2 is a diagram showing an embodiment of the present invention.

In this embodiment, as shown in the figure, a sprocket 1 and a platen 2. A pair of pinch rollers 5 and 6 are arranged in sequence in the paper conveyance direction, and the sprocket 1 is a small gear driven by a drive motor (not shown). It is driven clockwise as shown by the arrow from 8 to a large gear 9, a small gear 10 coaxial with the large gear, and an intermediate gear 11, and then a gear 12 coaxial with the sprocket 1. Further, the platen 2 is rotationally driven in a counterclockwise direction from a small gear 8, via a large gear 9, and a small gear 10, by a gear 13 coaxial with the platen 2, as shown by the arrow. Further, the pinch rollers 5 and 6 are moved from the gear 13 of the platen 2 via the intermediate gear 14 to the gears 15 and 16, so that the pinch roller 5 on the inside (as viewed from the paper 4) of the platen 2 is moved counterclockwise, and the pinch roller 6 on the outside are each rotated clockwise. and gear 8, 9.10.11.1
Gear train consisting of 2 and gears 8, 9, 10, 13, 14
, 15.16, the gear train is set so that (< baa .

In this embodiment configured as described above, the paper feed ilc of the pinch rollers 5 and 6 is
1. By increasing a and b, the slack in the paper between the sprocket l and the pinch rollers 5 and 6 is eliminated, and by reducing the paper feed amount s of the pinch roller 6 relative to the paper feed ia of the pinch roller 5, the platen It is possible to prevent the outer paper from leading to the second paper.

〔Effect of the invention〕

As explained above, according to the present invention, by changing the paper feed amount of a pair of pinch rollers and making the paper feed amount of the inner pinch roller larger than the paper feed amount of the outer pinch roller with respect to the platen, multiple sheets can be printed. When printing on copy paper, it is possible to prevent misalignment between layers and to enable stable paper feeding, even on paper that has weak holding power between sheets, such as paper stapled paper.

[Brief explanation of the drawing]

FIG. 1 is a diagram explaining the principle of the present invention, FIG. 2 is a diagram showing an embodiment of the present invention; FIG. 3 is a diagram showing the paper feeding mechanism of a conventional printer device. FIG. 4 is a diagram for explaining the problems of the prior art. In the figure, 1 is the sprocket, 2 is the platen, 4 is paper, 5.6 is a pinch roller, 7 is the print head shows.

Claims (1)

[Claims] 1. A mechanism (1) that engages with a paper feed hole to transport the paper, a platen (2), and a pair of pinch rollers (
5 and 6) are arranged in sequence, the continuous paper (4) is pushed and conveyed by the paper transport mechanism (1), and after printing on the platen (2), the paper is removed by pinch rollers (5, 6). (4
), the paper feed mechanism applies rotational driving force to both of the pair of pinch rollers (5, 6), and also controls the feeding amount of the roller (5) on the platen side by adjusting the feed amount of the roller (5) on the opposite side of the platen ( 6) A paper feeding mechanism for a printer device, characterized in that the feeding amount is larger than the feeding amount of item 6).