JPH0550727A - Ink ribbon feed mechanism of thermal transfer 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 the rotary direction of a ribbon feed motor at the time of the use of a multistrike ribbon to drive said motor. CONSTITUTION:The pinch roller 4 arranged on the lateral side of the thermal head 10 on a carrier 2, a planetary capstan roller 5 pressing a ribbon 9 along with the pinch roller 4, two torque pieces 6, 7 taking up the ribbon 9 and a reversibly rotatable ribbon feed motor 3 driving the torque pieces 6, 7 through idler gears 11, 12, 13 and also driving the planetary capstan roller 5 are provided. At the time of the unwinding of the ribbon, the pressure contact of the pinch roller 4 and the planetary capstan roller 5 is released by the reversal of the ribbon feed motor 3 to unwind the ribbon 9.

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 Conventionally, a ribbon feeding mechanism of this type is
The ribbon is fed by one capstan roller and one pinch roller provided on the winding side of the ribbon, and the completed ribbon is wound by the torque piece.

[0003]

In the above-described conventional ribbon feed mechanism, the ribbon feed direction is only one direction, so ribbon end detection in the case of using a multi-strike ribbon capable of printing the same portion several times. Occasionally, the ribbon cassette in which the multi-strike ribbon is stored must be reversely mounted, or the ribbon cassette must be completely exchanged to continue printing, which has the disadvantage that the time interval for ribbon cassette exchange operation cannot be extended.

The present invention provides an ink ribbon feed mechanism for enabling ribbon rewind feed and extending the ribbon end detection time and reducing the troublesome operation of reversing the ribbon cassette or replacing the ribbon cassette. is there.

[0005]

An ink ribbon feeding mechanism of a thermal transfer printer according to the present invention has a thermal head on a carrier slidable in parallel with a platen, and this thermal head interposes an ink ribbon and recording paper. In a thermal transfer printer having a roller pair that performs printing while moving in the digit direction while being in contact with the platen, and that includes a capstan motor and a pinch roller and is driven by a motor to frictionally drive the ink ribbon on the carrier, When the printable ink ribbon is rewound, a release mechanism is provided which separates the pressure contact between the capstan roller and the pinch roller in association with the reverse rotation of the motor for performing the ribbon feeding operation.

[0006]

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

FIG. 1 shows a printing operation according to an embodiment of the present invention. FIG. 1 (a) is a plan view, FIG. 1 (b) is a side view taken along arrow A in FIG. 1 (a), and FIG. FIG. 3 is a plan view of the present embodiment when the ribbon is rewound, and FIG. 3 is a plan view of the ribbon cassette of the present embodiment.

In this embodiment, a pinch roller 4 installed beside the thermal head 10 on the carrier 2, a planet capstan roller 5 that presses the ribbon 9 by the pinch roller 4, and two rolls for winding the ribbon 9 are provided. The torque feeds 6 and 7 and the torque feeds 6 and 7 via the idler gears 11, 12 and 13 and the planetary capstan roller 5 are also driven.
And have.

As shown in FIG. 1, the carrier 2 can slide in parallel with the platen 1. The thermal head 10 is mounted on the carrier 2 and is pressed by the platen 1 during printing. The planet capstan roller 5 is driven in the direction of arrow (a) when the ribbon feed motor 3 rotates counterclockwise. Further, the ribbon feed motor 3 rotates the torque piece 6 counterclockwise. The pinch roller 4 is supported by a carrier cover 8 and carries the ribbon 9 together with the planet capstan roller 5 in the direction of arrow B by a frictional force sandwiched between them. Further, the ribbon 9 is stored in the ribbon cassette 14 and wound around the ribbon core 15 that engages with the torque piece 6.

In the ribbon rewinding operation of this embodiment shown in FIG. 2, the thermal head 10 is retracted from the platen 1 side. The ribbon feed motor 3 rotates in the clockwise direction, and the rotational force thereof rotates the torque piece 7 in the clockwise direction, and further drives the planet capstan roller 5 to rotate in the arrow B direction and separates it from the pinch roller 4. The ribbon 9 is released from the planet capstan roller 5 and the pinch roller 4, is conveyed in the direction of arrow C, is stored in the ribbon cassette 14, and is wound around the ribbon core 16 that engages with the torque piece 7.

[0011]

As described above, according to the present invention, when the multi-strike ribbon is used, the ribbon feed motor can be driven by switching the rotation direction of the ribbon feed motor, so that the ribbon can be rewound and the time interval until the ribbon end is greatly increased. Can be extended to. Even for single strike ribbons and color ribbons, unused parts (the amount of ribbon feed from the pressing of the thermal head platen to the start of printing,
Alternatively, by rewinding (a ribbon feed amount from the end of printing to the retracting of the platen of the thermal head), there is an effect that the waste of the ribbon can be eliminated and the running cost can be reduced. Further, by releasing the ribbon at the time of reverse rotation by the planet capstan roller, it is possible to prevent wrinkles of the ink ribbon and ribbon breakage at the time of rewinding, and to effectively drive the ribbon. Further, by releasing the planet capstan roller at the ribbon end, there is an effect that the time and effort for exchanging the ribbon cassette can be reduced.

[Brief description of drawings]

1A and 1B show a printing operation of an embodiment of the present invention, FIG. 1A is a plan view, and FIG. 1B is a side view taken along arrow A in FIG. 1A.

FIG. 2 is a plan view at the time of rewinding the ribbon 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 planetary capstan roller 6,7 torque piece 8 carrier cover 9 ribbon 10 thermal head 11,12,13 idler gear 14 ribbon cassette 15,16 ribbon core

Claims (1)

[Claims] 1. A thermal head is provided on a carrier that is slidable in parallel with a platen, and the thermal head is in contact with the platen via an ink ribbon and a recording paper while moving in the digit direction to perform printing. In a thermal transfer printer having a roller pair that includes a stun motor and a pinch roller and is driven by a motor to frictionally drive the ink ribbon on the carrier, a ribbon feed operation is performed when the ink ribbon that can be printed many times is rewound. An ink ribbon feeding mechanism for a thermal transfer printer, comprising: a releasing mechanism that separates the pressure contact between the capstan roller and the pinch roller in association with the reverse rotation of the motor.