JPH0219240Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a paper feeding device for a printing device that is capable of adjusting and correcting the skew of paper.

In particular, there are the following problems with paper feeding devices of printing devices that use continuous paper. That is, the problem is that the ruled lines on the paper do not match the ruled lines of the printed result, and this is called skew feeding of the paper. This skew feeding of paper is a particularly noticeable problem in dot printers that print in dot row units. For this equality, a paper skew adjustment mechanism is required.
This will be explained below with reference to FIGS. 1 and 2.

A pair of paper feed tractors 1 are rotationally driven by a paper feed motor 2 to which a pulley 3 is attached, via a drive shaft 6 to which a belt 4 and a driven pulley 5 are attached. Both ends of the drive shaft 6 are rotatably supported by first and second frames 8 and 9 via bearings 7. The second frame 9 is attached to the first frame 8 with a bolt 1.
0, but the positioning pin 1
1. It is positioned by hitting the adjustment plate 12 attached with bolts 13. Printing is performed in units of dot rows by a hammer unit 16 having printing hammers for dot printing provided at equal intervals in the digit direction. The platen 15 supports the impact of the printing hammer during printing.

Generally, the center line of one line shown in FIG. 2A after printing is inclined with respect to the paper 14 as shown. This is because the position error of the left and right tractors 1 with respect to the hammer unit 16 appears due to the accumulation of errors in many parts, and this inclination is the skew of the paper 14. This skewing of the paper 14 is corrected by adjustment when the second frame 9 is attached using the positioning pins 11 and the adjustment plate 12. By moving the second frame 9 in the vertical direction in the figure, the inclination angle of the drive shaft 6 in the digit direction can be changed and adjusted.

A relatively large second frame 9 for this adjustment
There is a problem that the paper feeding device becomes expensive and the rigidity of the frames 8 and 9 decreases due to the need for positioning pins 11, adjustment plates 12, etc. used when attaching and detaching. be. When the rigidity of the frames 8 and 9 decreases, the vibration caused by the reciprocating motion of the hammer unit 16 becomes particularly large, especially in the direction of the digits at the tip of the second frame 9, which causes slight displacement of the paper 14 in the direction of the digits. This had the disadvantage of deteriorating print quality.

The purpose of the present invention is to eliminate the above-mentioned drawbacks of the prior art, improve the rigidity of the frame, and provide a paper feeding device at a low cost.

The present invention focuses on the fact that changing the mounting position of the drive shaft is necessary to adjust the skew of paper, and has devised a way to change only the mounting position of the bearing that supports the drive shaft. . The present invention will be described below with reference to the drawings.

As shown in FIG. 3, the frame 80 extends to the upper end, and the drive shaft 6 is inserted into the elongated hole 81 extending in the paper feeding direction.
A bearing 70 that rotatably supports the is movably attached. The bearing 70 is attached to the frame 80 through the elongated hole 71 with a screw 72. Therefore, while looking at the printing results, move the left bearing 70 vertically in the figure so that the paper 14 does not skew.
After the skew has been corrected, the bearing 70 is fixed to the frame 80 by tightening the screw 72.

As described above, the present invention eliminates the relatively large second frame and moves the bearing to adjust the inclination of the drive shaft. This improves the rigidity of the frame and eliminates the need for positioning pins and adjustment plates. Since the configuration is simple, the paper feeding device can be provided at low cost.

[Brief explanation of the drawing]

Figures 1 and 2 are side and front views showing an example of a conventional device, Figure 3 is a side view of an embodiment of the device of the present invention, and Figure 4 shows the vicinity of the bearing that constitutes the device of the present invention. The enlarged side view shown in Fig. 5 is the BB of Fig. 4.
FIG. In the figure, 1 is a tractor, 6 is a drive shaft, and 70
80 is a bearing, and 80 is a frame.

Claims (1)

[Claims for Utility Model Registration] A hammer unit that stores and holds a plurality of dot printing hammers provided at equal intervals along the digit direction and moves back and forth along the digit direction, and a hammer unit provided above the hammer unit. A pair of left and right paper feed tractors,
A dot line printer having a drive shaft that drives the tractor, and bearings that rotatably support both ends of the drive shaft and are attached to a frame, comprising: a long hole provided in the frame and extending in the paper feeding direction; A bearing is mounted in the elongated hole so as to be movable along the paper feeding direction, and has an elongated hole in the flange portion extending in the paper feeding direction, and a screw passes through the elongated hole of the bearing and fixes the bearing to the frame. 1. A paper feeding device for a dot line printer, characterized in that at least one of the bearings is mounted on a frame so as to be movable in a paper feeding direction.