JPH0550728A - Ribbon feed mechanism of thermal transfer serial printer - Google Patents

Abstract

PURPOSE:To enable the unwinding of a ribbon and to extend the time interval until a ribbon end to a large extent by changing over the rotary direction of a ribbon feed motor at the time of the use of a multistrike ribbon to drive said motor. CONSTITUTION:The title mechanism is provided with a capstan roller 5 arranged on the lateral side of the thermal head 12 on a carrier 2, a pinch roller 4 pressing a ribbon 1 to the capstan roller 5, a pressure release mechanism containing the tension lever 10 separating the pinch roller 4 and the capstan roller 5, two torque pieces 6, 7 taking up the ribbon 11 and the ribbon feed motor 3 having the torque pieces 6, 7 and the capstan roller 5. At the time of the unwinding of the ribbon, the pinch roller 4 and the capstan roller 5 are separated by the reversal of the ribbon feed motor 3 through the tension lever 10 to freely unwind the ribbon 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ribbon feed mechanism for feeding an ink ribbon in a thermal transfer serial printer.

[0002]

2. Description of the Related Art In the conventional printing method of a thermal transfer serial printer, an ink ribbon is housed in a ribbon cassette which can be turned upside down, and is mounted on a carriage having one winding torque piece, a capstan roller and a pinch roller for printing. Was being done.

[0003]

In the above-mentioned conventional ribbon feed mechanism, the ribbon feed direction is only one direction. Therefore, when a multi-strike ribbon capable of printing the same portion several times is used, When this happens, the ribbon cassette that houses the multi-strike ribbon must be reversed or the ribbon cassette must be replaced to continue printing, and the time interval between the ribbon cassette inversion operation and ribbon cassette replacement operation cannot be extended. There is a drawback. Further, when the capstan roller is reversed and the ribbon rewind feed is performed, the ribbon is sandwiched between the capstan roller and the pinch roller, so that there is a drawback that ribbon wrinkles and ribbon breakage occur.

The present invention provides a ribbon feed mechanism for enabling ribbon rewind feed and extending the ribbon end detection time, and reducing the inconvenience of a ribbon cassette reversing operation or a ribbon cassette replacing operation. .

[0005]

A ribbon feeding mechanism of a thermal transfer serial printer of the present invention has a thermal head on a carrier slidable in parallel with a platen, and a ribbon wound on a sheet wound on the platen. In a thermal transfer serial printer for printing, a pinch roller for pressing the ribbon against a capstan roller installed on the carrier, two torque pieces for winding the ribbon, and a drive motor for driving the torque piece. And a pressure release mechanism for separating the pinch roller from the capstan roller when the ribbon is rewound by switching the rotation direction of the drive motor.

[0006]

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

FIG. 1 is a plan view of an embodiment of the present invention, FIG. 2 is a sectional view of a pressing force releasing mechanism of a pinch roller of this embodiment, and FIG. 3 is a plan view of a ribbon cassette of this embodiment.

In this embodiment, a capstan roller 5 installed beside the thermal head 12 on the carrier 2, a pinch roller 4 for pressing the ribbon 11 against the capstan roller 5, and the pinch roller 4 and the capstan. A pressure release mechanism including a tension lever 10 for separating the roller 5; two torque pieces 6 and 7 for winding the ribbon 11;
A ribbon feed motor 3 for driving the torque pieces 6 and 7 and the capstan roller 5 is provided.

The carrier 2 is slidable in parallel with the platen 1. The thermal head 12 is mounted on the carrier 2,
The platen 1 is pressed during printing. The ribbon feed motor 3 rotates counterclockwise, and its rotational force is transmitted to the capstan roller 5, which further rotates the torque piece 6 counterclockwise. The ribbon 11 is fed in the direction of arrow A because it is sandwiched between the capstan roller 5 and the pinch roller 4 by the pinch roller spring 9. Further, the ribbon core 21 is housed in the ribbon cassette 20 and wound around the ribbon core 21 that engages with the torque piece 6.

Next, the ribbon rewinding operation will be described. The thermal head 12 is retracted from the platen 1 side in the direction of arrow D. The ribbon feed motor 3 rotates clockwise,
The rotational force rotates the torque piece 7 in the clockwise direction and is further transmitted to the capstan roller 5. In addition, as shown in FIG. 2, the ribbon feed motor 3 that rotates clockwise is used.
Transmits a counterclockwise rotational force to the gear 19. This is transmitted to the coil spring 17 and the tension pressed by the cap 18 acts as a force for locking the tension lever 10. As a result, the tension lever 10 works in the direction of arrow B, pulls the pinch roller 4 away from the capstan roller 5, and frees the ribbon 11 to feed it in the direction of arrow C. The ribbon 11 fed in the direction of arrow C is
The ribbon cassette 20 is housed in the ribbon cassette 20 and wound around the ribbon core 22 that engages with the torque piece 7.

During printing, the mechanism works in such a direction that the gear 19 rotates clockwise and the coil spring 17 contracts, the tension lever 10 is not locked, and the relationship with the gear 19 is via the friction plate 16. And slipped. Therefore, the pinch roller 4 is brought into contact with the capstan roller 5 by the force of the pinch roller spring 9.

[0012]

As described above, the present invention makes it possible to rewind the ribbon by switching the rotation direction of the ribbon feed motor when the multi-strike ribbon is used, and to greatly reduce the time until the ribbon end. Can be stretched. Further, even in a single strike or a color ink ribbon, by rewinding the unused portion, there is an effect that the waste of the ribbon can be eliminated and the running cost of the ribbon can be reduced. Further, by pulling the pinch roller away from the multi-strike ribbon by the tension lever, it is possible to prevent wrinkles and folds of the ink ribbon at the time of rewinding and to effectively drive the ribbon.

[Brief description of drawings]

FIG. 1 is a plan view of a printing operation and ribbon rewinding according to an embodiment of the present invention.

FIG. 2 is a sectional view of a pressing force releasing mechanism of a pinch roller of the present embodiment.

FIG. 3 is a plan view of the ribbon cassette of this embodiment.

[Explanation of symbols] 1 platen 2 carrier 3 ribbon feed motor 4 pinch roller 5 capstan roller 6,7 torque piece 8 pinch roller arm 9 pinch roller spring 10 tension lever 11 ribbon 12 thermal head 13,14,15 idler gear 16 friction plate 17 Coil Spring 18 Cap 19 Gear 20 Ribbon Cassette 21, 22 Ribbon Core

Claims (1)

[Claims] 1. A thermal transfer serial printer having a thermal head on a carrier slidable parallel to a platen and printing on a paper wound around the platen via a ribbon, the thermal transfer serial printer being installed on the carrier. Pinch roller that presses the ribbon against a capstan roller, two torque pieces that wind the ribbon, a drive motor that drives the torque piece, and winding of the ribbon by switching the rotation direction of the drive motor. A ribbon feeding mechanism for a thermal transfer serial printer, comprising: a pressure releasing mechanism that pulls the pinch roller away from the capstan roller at the time of returning.