JPH04368868A - Ink ribbon feed mechanism - Google Patents

Abstract

PURPOSE:To prevent printing wrinkles by removing the slackening of the ink ribbon of a printing part by detecting the position of the ink ribbon by a sensor and shaking a crown guide roller by a solenoid through an arm to feed the ink ribbon in a meandering state. CONSTITUTION:The position of an ink ribbon 2 in the lateral direction thereof is detected by sensors 10, 11. When the sensor 10 detects that the edge of the ink ribbon 2 passes the position of the sensor 10, a crown guide roller 8 is shaken in the direction moving the ink ribbon 2 toward the position of the sensor 11 by a solenoid 12 through an arm 13 and the ink ribbon 2 is alternately changed over toward the sensor 10 or the sensor 11 in synchronous relationship to be allowed to slightly meander. By this constitution, the slackening of the ink ribbon of a printing part is removed to prevent printing wrinkles.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink ribbon feed mechanism, and more particularly to an ink ribbon feed mechanism for a thermal printer.

0002

2. Description of the Related Art A conventional ink ribbon feed mechanism has a structure in which guide rollers 15 and 17 are arranged on the left and right sides with a thermal print head 14 in between, as shown in FIG. ribbon 16
To prevent wrinkles, the center part of the roller has a crown shape that is slightly larger than the end face of the roller, and the guide roller 17
At the same time, steps with a width approximately 1 mm larger than the width of the ink ribbon 16 were provided at both ends to guide the ink ribbon 16.

0003

[Problems to be Solved by the Invention] In this conventional ink ribbon feed mechanism, in order to prevent the ink ribbon from sagging, a certain braking force is applied to the set roller on the ink ribbon supply side to apply tension to the ink ribbon, and the crown guide roller The ink ribbon is wound so that tension is created in the center, but if there are variations in the braking force, or the printing is continuously shifted to one side in the width direction of the ink ribbon, or friction is applied. There was a problem that sagging occurred on the ink ribbon, and printing wrinkles occurred due to wrinkles in the ribbon.

0004

[Means for Solving the Problems] The ink ribbon feed mechanism of the present invention has two ink ribbon width position detection sensors disposed between the crown guide roller on the take-up side of the ink ribbon to be fed and the print head, and It includes a solenoid that swings the guide roller by using one end as a fulcrum and moving the other end, and when the ink ribbon width position detection sensor detects movement in one width direction of the ink ribbon, the solenoid causes the ink ribbon to change in width. The crown guide roller is oscillated so as to move in the opposite direction, and when movement of the ink ribbon in the opposite direction in the width direction is detected, the solenoid causes the ink ribbon to move in one direction in the width direction. It is characterized by swinging the crown guide roller.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a front view of an embodiment of the present invention, and FIG. 2 is a side view.

The ink ribbon 2 in the ink ribbon cassette 1 is guided by a guide roller 5 from a set roller 4 to which a certain braking force is applied in order to apply tension to the ink ribbon when printing on paper 3, and is guided by a guide roller 5 between a thermal print head 6 and a platen 7. It passes through a crown guide roller 8 and is wound up by a feed roller 9. The crown guide roller 8 is attached so as to be able to swing around one end.

The position of the ink ribbon 2 in the width direction is detected by the sensor 10 and the sensor 11, and when the sensor 10 detects that the edge of the ink ribbon 2 has passed the position of the sensor 10, the solenoid 12 sends the crown via the arm 13. The guide roller 8 is swung in the direction in which the ink ribbon moves toward the sensor 11, and the ink ribbon 2 is alternately and slowly moved in the direction of the sensor 10 or sensor 11 at a constant cycle, and the ink ribbon 6 is moved slightly. Make it meander.

[0009]

As explained above, the present invention detects the position of the ink ribbon using a sensor, and uses a solenoid to swing the crown guide roller through the arm to feed the ink ribbon in a meandering manner. This has the effect of removing sag from the ribbon and preventing printing wrinkles.

[Brief explanation of drawings]

FIG. 1 is a front view of an embodiment of the present invention.

FIG. 2 is a side view of the embodiment shown in FIG. 1;

FIG. 3 is a side view of a conventional ink ribbon feed mechanism.

[Explanation of symbols]

1 Ink ribbon cassette 2 Ink ribbon 3 Paper 4 Set roller 5 Guide roller 6 Thermal print head 7 Platen 8 Crown guide roller 9 Feed roller 10 Sensor 11 Sensor 12 Solenoid 13 Arm 14 Thermal print head 15 Crown guide roller 16 Ink ribbon 17 Guide roller

Claims (1)

[Claims] 1. Two ink ribbon width position detection sensors are arranged between a crown guide roller on the take-up side of the ink ribbon to be fed and the print head, and the crown guide roller is oscillated by using one end as a fulcrum and moving the other end. The crown guide roller includes a solenoid for moving the ink ribbon, and when the ink ribbon width position detection sensor detects movement of the ink ribbon in one width direction, the solenoid moves the ink ribbon in the opposite direction of the width direction. and when detecting movement of the ink ribbon in the opposite direction to the width direction, the solenoid causes the crown guide roller to swing so that the ink ribbon moves in one direction in the width direction. Ink ribbon feed mechanism.