JPH01317785A - Thermal transfer printer - Google Patents

Abstract

PURPOSE:To shorten an empty feed operation time or the time required in printing without increasing the scale and capacity of a take-up shaft driving apparatus by mounting an empty feed control means for releasing a printing head from a platen and taking up an ink ribbon by the take-up shaft while feeding the same to take-up part by a ribbon feed roller. CONSTITUTION:When the ink having a color to be thermally transferred of a color ink ribbon 4 is set to the place (printing position) corresponding to a printing head 11, a motor 16 is driven in such a state that the contact of the printing head with a platen 9 under pressure is released and the ink ribbon 4 is taken up by a take-up shaft 14 while fed to a take-up part by a ribbon feed roller 15. When a marker 5 of a color to be thermally transferred is detected by a marker detector 12, the driving of the motor 16 is stopped. This ribbon empty feed is performed at the time of non-printing, for example, at the time of the return of a carriage as well as at the time of the feed of paper. The ribbon feed speed at the time of the empty feed of the ribbon is set so as to be higher than that of the ribbon at the time of printing.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a thermal transfer printer, and more particularly to a thermal transfer printer capable of performing multicolor printing using color ink ribbons.

Prior Art and Problems of the Invention For example, when performing multicolor printing with a serial thermal transfer printer, color ink ribbons are used. Color ink ribbons are generally made by applying ink in three colors, yellow, magenta, and cyan, in series on the base of a book, separated by color identification markers, and are placed in a cassette. The length of the ink application area between the markers is approximately one line. Then, by thermally transferring any one type of ink, or thermally transferring two or three types of ink in a layered manner, multicolor printing of a plurality of colors is performed.

When printing in yellow, magenta, or cyan, ink of that color is transferred.

When printing in red, green, or violet, two types of ink are thermally transferred in an overlapping manner. For example, when printing in red, yellow and magenta inks are thermally transferred in layers. Furthermore, when printing in black, three types of ink are thermally transferred in layers. Switching of the three colors of ink is performed on a line-by-line basis. Therefore, when performing multicolor printing, the print head is typically scanned three times for each line.

A thermal transfer printer is provided with a marker sensor to identify the color of ink using a color identification marker on an ink ribbon. When ink of a predetermined color is thermally transferred, the ink ribbon is continuously fed until the marker sensor detects a color identification marker in front of the ink of the color to be thermally transferred.

Conventionally, this idle feeding has been performed by the following two methods. The first step, similar to the printing process, is to press the head to the platen, move the carriage in the printing direction, pay out and take up the ribbon, and move the carriage until the marker sensor detects a predetermined color identification marker. This is a method in which the ribbon is repeatedly fed out and wound up by returning and moving the carriage. The second method is to wind up the ink ribbon by rotating a winding shaft using a winding motor provided independently of the drive motor of the carriage, without pressing the head onto the platen.

The first method has a problem in that it takes time because the carriage repeats reciprocating motion until the marker sensor detects a predetermined color identification marker. Furthermore, since the ribbon is fed with the head crimped to the platen,
When the ink is in contact with the paper, such as when printing,
There is a problem in that slips tend to occur between the ink ribbon and the recording paper, resulting in ink stains on the recording paper.

In the second method described above, the ink ribbon is fed out and wound up by winding the ink ribbon using the rotational force of the winding shaft, so when the ink ribbon winding diameter becomes large. Furthermore, since the winding motor requires a large winding torque, there is a problem in that the winding motor needs to be made larger, and it also takes time because the winding speed cannot be increased.

An object of the present invention is to provide a thermal transfer printer that can shorten the time spent on feeding the ribbon in order to set the ink of the color to be thermally transferred at the printing position, and that does not require an enlarged take-up motor. do.

Means for Solving the Problems A thermal transfer printer according to the present invention is provided between an ink ribbon winding part and a peeling part where the ink ribbon of the carriage in which the ink ribbon cassette is mounted is peeled off from the recording paper, and the ink ribbon is wound therein. A ribbon feed roller is used to send the ribbon to the take-up section, and when setting the colored ink ribbon to be thermally transferred to the printing position, the print head is released from the platen and the ink ribbon is conveyed to the take-up section by the ribbon feed roller. The present invention is characterized in that it is equipped with an idle feed control means for winding the ink ribbon onto a winding shaft.

Effect of the Invention When setting ink of a color to be thermally transferred on a color ink ribbon at a printing position, the print head is released from the platen. Then, the ink ribbon is conveyed to the winding section by the ribbon feed roller, and the ink ribbon is wound around the winding shaft.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1 to 5 show a carriage and an ink ribbon cassette attached thereto.

In Figures 1 to 3, the main winding core (2) is rotatably attached to the right side of the cassette (1), and the main winding core (2) is fitted to the left side of the winding shaft (14) of the carriage (10). A rotating winding core (3) is provided. and,
Color ink ribbon (
4) is wrapped. The color ink ribbon (4) has
As shown in FIG. 6, three colors of ink, yellow (Y), magenta (M), and cyan (C), each having a length of approximately -row, are repeatedly applied in series. and,
A color identification marker (5) for identifying the color of the ink is provided at the beginning of each color of ink.

In addition, a vertical groove (6) is formed in the center of the rear surface of the cassette (1), and a claw (7) extending in the left-right direction is formed in the center of the bottom height of this groove (8). has been done.

A claw (8) is also formed on the front surface of the cassette (11).

The carriage (lO) includes a print head (11) having a plurality of heating elements (not shown), a marker sensor (12), an original winding shaft (13), a winding shaft (14), and a ribbon feeding roller (1
5), a stepping motor (1B) for driving the winding shaft and the ribbon feed roller, an engaging protrusion (17) capable of engaging with a pawl (8) formed on the front end surface of the cassette (1), etc. are provided. .

The winding shaft (14) includes a cylindrical support shaft (22) that is rotatably fitted into a vertical shaft (21) provided on the carriage (lO) and has a flange (22a) at the bottom thereof, and a shaft (21). A winding cam (23) rotatably fitted to the upper part of the shaft so as not to come off the shaft and having a flange (23a) at the lower part; a gear (24) rotatably fitted to the spindle (22); Flange (2) of take-off cam (23)
An annular friction plate (2) interposed between the gear (24) and the gear (24)
5), the flange (22a) of the support shaft (22), and the gear (2).
4) is fitted onto the support shaft (22) and the gear (
24) toward the winding cam (23). The spindle (22) and the winding cam (2
3) is connected by the upper part of the support shaft (22) being press-fitted into the hollow part of the winding cam (23). Spring (2
B) A washer (27) is interposed between the upper end and the gear (24). The take-up core (3) of the cassette (1) is engaged with the take-up cam (23).

The ribbon feeding roller (15) is provided between the peeling section where the ink ribbon (4) is peeled off from the recording paper and the ink ribbon winding section, and is connected to a drive roller (15) rotatably attached to the carriage (10). 31) and a drive roller (31)
It consists of a pinching rubber roller (32) that can move toward and away from the roller. The diameter of the drive roller (31) is smaller than the maximum value of the winding diameter of the ink ribbon (4).

A gear (33) is provided at the lower end of the drive roller (31). The rubber roller (32) is attached to the carriage (10
) is rotatably attached to one end of a roller actuating lever (34) that is attached to be able to swing freely about the center of its length. One end is the roller actuation lever (34
), the rubber roller (32) is biased against the drive roller (31) by a coil spring (35) whose other end is fixed to the carriage (lO).

The output shaft of the Stellar pin motor (1B) has a gear (3B).
is installed. An idle gear (39) having a large gear (37) and a small gear (3B) is rotatably arranged between the Stellar pin motor (16) and the take-up shaft (14). The large gear (37) meshes with a gear (3B) provided on the output shaft. The small gear (38) meshes with the gear (24) of the winding shaft (14).

The gear (24) of the take-up shaft (14) and the gear (33) of the drive roller (31) are connected by an idle gear (40) rotatably attached to the carriage (10).

A shaft (41) extending along the rear lower edge of the cassette (1) attached thereto is rotatably attached to the carriage (lO). A cassette fixing lever (42) that can be engaged with a claw (7) on the rear surface of the cassette (1) is fixed at the center of the length of the shaft (41). A gear (43) is attached to the left end of this shaft (41). Between the left end of the shaft (41) and the roller operating lever (34), there is a movable member (44) with a rack extending in the front-rear direction.
) are arranged so that they can move freely back and forth. Movable member with rack (
A first rack (45) and a second rack (46) are formed on the rear upper surface and the front left side surface of 44), respectively.

The first rack (45) meshes with the gear (48) of the shaft (41).

A lever actuating cam (48) having a gear (47) at its lower part is rotatably disposed on the left side of the other end of the roller actuating lever (34). This gear (47) and the second rack (46) of the movable member (44) are connected to the carriage (1
0) by an idle gear (49) rotatably attached.

To attach the cassette (1) to the carriage (lO), make sure that the claw (8) on the front side of the cassette (1) is attached to the carriage (10).
the carriage (1) so as to engage with the engaging projection (17) of the
After placing the cassette (1) on the cassette (1), the cassette fixing lever (42) is rotated to engage the lever (42) with the claw (7). By rotating the lever in this way, the first rack (
45) and the gear (43) of the shaft (41) rotate in the same direction, and the movable member (44) moves rearward.

As a result, the idle gear (49) meshing with the second rack (46) rotates, and the cam (48) reaches a position where it does not interfere with the roller operating lever (34). Therefore, the rubber roller (32) attached to the roller actuation lever (34) is biased toward the drive roller (31) by the biasing force of the spring, and the ink ribbon (4) is moved between both rollers (31) ( 32). This condition is shown in FIGS. 4 and 5.

During printing, the print head (11) is connected to the platen (9).
), the carriage (10) moves,
The motor (1B) moves the ink ribbon (4) onto the take-up shaft (
14).

When setting the ink of the color to be thermally transferred on the color ink ribbon (4) to a location (printing position) corresponding to the print head (11), the pressure of the print head (11) to the platen (9) is released. In this state, the motor (16) is driven, and the ink ribbon (4) is transported to the winding section by the ribbon feed roller (15) and wound around the winding shaft (14). When the marker (5) of the color to be thermally transferred is detected by the marker detector (12), the driving of the motor (IB) is stopped. Such ribbon feeding is performed during non-printing, for example, when the carriage returns or when paper is conveyed. Further, the ribbon conveyance speed during such ribbon feeding is set higher than the ribbon conveyance speed during printing.

When removing the cassette (1) from the carriage (lO), rotate the cassette fixing lever (42) in the direction shown by the arrow in Figure 5 to release the engagement between the lever (42) and the claw (7). . Then, move the cassette (1) onto the carriage (
10) Take it out.

By rotating the lever (42) as described above,
The gear (43) of the shaft (41) that engages with the first rack (45) rotates in the same direction, and the movable member (40) moves forward.This causes it to engage with the second rack (4) as well. The idle gear (49) rotates and the cam (48)
rotates in the direction of the arrow in Fig. 4 and presses /(-(34). Therefore, the lever (34) rotates in the direction of the arrow and the rubber roller (32) moves against the drive roller (31). distance from.

Effects of the Invention In the thermal transfer printer according to the present invention, the ink ribbon is fed out during idle feeding by the rotational force of the ink ribbon feed roller rather than the rotational force of the take-up shaft. Even if the size increases, a large winding torque is no longer required. Therefore, there is no need to increase the size and capacity of the drive device for the winding shaft.

Since the ribbon conveyance speed during idle feeding can be increased, the idle feeding operation time can be shortened. In addition, since the idle feeding operation can be performed during the process of moving the carriage from one printing position to the next printing position, for example, when returning the carriage, when feeding paper, etc., the time required for printing is shortened.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a perspective view showing a carriage and an ink ribbon cassette, FIG. 2 is a partially cutaway plan view showing the carriage, and FIG. 3 is taken along the line ■-■ in FIG. 4 is a plan view showing the ink ribbon cassette mounted on the carriage; FIG. 5 is a sectional view taken along the line V-v in FIG. 4; and FIG. 6 is a partially enlarged sectional view of the ink ribbon. It is an expanded view. (1) Ink ribbon cassette, (9) Platen, (14) Take-up shaft, (15) Ribbon feed roller, (16) Stepping motor. that's all

Claims (2)

[Claims] (1) A ribbon feeding roller provided between a peeling section where the ink ribbon of the carriage to which the ink ribbon cassette is attached is separated from the recording paper and an ink ribbon winding section and for feeding the ink ribbon to the winding section; When setting the ink of the color to be thermally transferred on the color ink ribbon to the printing position, the print head is released from the platen, and the ink ribbon is wound around the take-up shaft while being conveyed to the take-up section by the ribbon feed roller. A thermal transfer printer with a free feed control means. (2) The speed at which the ink ribbon is wound onto the take-up shaft while the ink ribbon is conveyed to the take-up section by the ribbon feed roller is faster than the conveyance speed of the ink ribbon during printing.
Thermal transfer printer described.