JPH0430912B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printing mechanism that enables reciprocating printing in a thermal transfer printer that thermally transfers ink from an ink ribbon onto information recording paper, which is plain paper.

[Prior Art] Generally, the basic configuration of a conventional thermal transfer printer is as shown in FIG.

That is, the printer 1 includes a platen 3 that winds up the recording paper 2 upward at each line feed, a ribbon cassette 4 that stores an ink ribbon, and a ribbon cassette 4 that can approach and retreat from the platen 3, and when printing, A print head 5 that presses an ink ribbon onto the recording paper 2 to print, and a carriage 6 that reciprocates the print head 5 and the ribbon cassette 4 within a predetermined range in both left and right directions with respect to the platen 3.
have. This carriage 6 has one end slidably engaged with a guide rail 7, and the other end fixed to a timing belt 8 that moves in both left and right directions by a drive device (not shown), and is connected to the printing head 5 and the ribbon. This is for moving the cassette 4. Reference numeral 9 in FIG. 6 is a ribbon drive shaft for transporting the ink ribbon stored in the ribbon cassette 4, and this ribbon drive shaft 9 allows the ink ribbon to have a relative speed of zero with respect to the platen 3. That is, the paper is transported at substantially the same speed as the moving speed of the carriage 6, and in a direction opposite to the printing direction. On the other hand, the ribbon cassette 4
As shown in FIGS. 7 and 8, the ink ribbon 10 is unused on a reel 11.
The reel 11 is the ink ribbon 1.
is rotatably supported by a shaft pin 12 that supports 0,
On the other hand, the used ink ribbon 10, on which ink has been transferred to the recording paper through the print head 5, is wound up onto a take-up reel 13 which is supported by the ribbon drive shaft 9. Incidentally, reference numeral 14 in FIG. 7 is a guide pin for regulating the movement of the ink ribbon and allowing it to pass through the print head 5.

In the printing mechanism of a thermal transfer printer configured as described above, printing is generally performed during the forward motion in which the carriage 6 moves to the right with respect to the platen 3, and the carriage 6 starts moving to the right. When printing, the print head 5 approaches the platen 3 and presses the ink ribbon 10 against the recording paper 2, and printing is performed on the recording paper 2 by the movement of the print head 5 and the movement of the ink ribbon 10. .

[Problem that the invention seeks to solve]

However, the conventional printing mechanism described above has a problem in that it is not possible to print on the recording paper 2 when the print head 5 performs a backward movement of moving leftward with respect to the platen 3.

That is, the print head 5 starts printing from a predetermined position on the left side where printing should start, moves to the right side, and returns from the right position where a predetermined number of characters have been printed to the predetermined left side position where printing should start again. However, while the print head 5 is performing a forward movement of moving rightward with respect to the platen 3 and printing, the ink ribbon 10 is moved to the recording surface R of the print head 5 as shown in FIG. The printing head 5 is transported to the left with respect to the platen 3, and at the same speed as the print head 5. By doing this, the relative speed between the recording paper 2 and the ink ribbon 10 passing over the recording surface R of the print head 5 becomes zero, so that a clean print is made on the recording paper 2, and the recording paper 2 is not smeared with ink. Things will disappear.

By the way, when attempting to print on the recording paper 2 when the print head 5 performs a backward movement to return to a predetermined position on the left side, the ink ribbon 10 must be transported in the opposite direction to the forward movement, that is, to the right. . However, if the ink ribbon 10 is moved to the right, it is possible to reduce the relative speed between the recording paper 2 and the ink ribbon 10 to zero; Ink ribbon 1 that got twisted and the ink came out
Since 0 is returned, printing cannot be performed after all. On the other hand, if an attempt is made to print by continuing to move the ink ribbon 10 to the left during the return operation of the print head 5, the recording paper 2 and the ink ribbon 10 will rub, and the recording paper 2 will be smeared with ink, making it impossible to print. become. In this way, the thermal transfer printer has to transport the ink ribbon 10 in the opposite direction to the direction of movement of the print head 5, and since the ink ribbon is a one-time item that cannot be used again, it is difficult to perform conventional printing. The mechanism was not capable of reciprocating printing.

[Means for solving problems]

The present invention has been made in view of the above-mentioned problems, and provides a printing mechanism capable of reciprocating printing, the means of which is capable of moving forward and backward with respect to the platen, and has two Two print heads are provided corresponding to the ribbon cassettes, one of which is pressed against the platen when printing is moved to the left, and the other is pressed against the platen when printing is moved to the right. 2. A thermal transfer printer comprising: two ribbon drive shafts each configured to transport and wind up an ink ribbon passing through a print head in a direction opposite to the direction of movement of the print head during each printing. This is done by a reciprocating printing mechanism.

[Effect]

Since the present invention is a technical means having the above-mentioned configuration, during the forward movement in which the print head moves to the right, one of the print heads is used to move the ink ribbon over the recording surface relative to the platen. When the ink ribbon passes through the ink ribbon so that its speed is zero, and conversely, during the return operation in which the print head moves to the left, the other print head is used to pass the ink ribbon over the recording surface so that the relative speed with the platen is zero. By passing the recording paper through the platen, it is possible to perform reciprocating printing from both left and right directions on the recording paper that is stationary on the platen.

〔Example〕

Embodiments of the present invention will be described below based on the accompanying drawings.

1 to 3 show a reciprocating printing mechanism according to a first embodiment of the present invention.

This stamp mechanism enables reciprocating printing.
As shown in FIG. 1, there is a ribbon cassette C having two ribbon cassettes, namely a normal printing ribbon cassette 16 and a reverse printing ribbon cassette 15, and two printing heads, namely a normal printing head 1.
As shown in FIG. It is carried by a carriage 14 that reciprocates by a timing belt 8 driven by a timing belt 8, and reciprocates in both left and right directions with respect to the platen 3.

Normally, the normal printing head 18 approaches the platen 3 direction to print when the carriage 14 moves to the right in a forward motion, and when the carriage 14 moves in a backward motion to the left, the head 18 approaches the platen 3 to print. On the other hand, the reverse printing head 17 is separated from the platen 3 when the carriage 14 moves forward;
When the printer performs a backward operation, it approaches three directions of the platen and performs printing.

On the other hand, as shown in FIG. 1, the normal printing ribbon cassette 16 stores an ink ribbon 24 for normal printing.
is wound on the reel 27 in advance, and the reel 27
is rotatably supported by a shaft pin 27a. Then, the ink ribbon 24 for normal printing passes over the recording surface of the head 18 for normal printing, and is wound up onto a take-up reel 25. That is, the take-up reel 25 is
When the carriage 14 moves forward in conjunction with the ribbon drive shaft 28 for normal printing of the carriage 14 shown in FIG. 3, the ink ribbon rotates counterclockwise in FIG. 24 and the platen 3 (moved to the left with respect to the platen 3 and at the same speed as the moving speed of the carriage 14), the ink is thermally transferred onto the recording paper 2, and the ink ribbon has completed the transfer. 2
4.

On the other hand, the reverse printing ribbon cassette 15 stores an ink ribbon 19 for reverse printing, and the ink ribbon 19 for reverse printing is previously wound around a reel 22, and the reel 22 is rotatably mounted on a shaft pin 22a. It is pivoted on. Then, the ink ribbon 19 for reverse printing passes over the recording surface of the head 17 for reverse printing and is wound onto the take-up reel 20 . That is, the take-up reel 20 is interlocked with the reverse printing ribbon drive shaft 23 of the carriage 14 shown in FIG.
When the carriage 14 makes a backward movement, it rotates clockwise in FIG. The ink ribbon 19 is moved at the same speed as the moving speed of the carriage 14) to thermally transfer the ink onto the recording paper 2, and the ink ribbon 19 that has completed the transfer is wound up.

In FIG. 1, reference numeral P is a guide pin that regulates the direction of the ink ribbon, and reference numeral F is a ribbon end detection device that detects the end of the ink ribbon. When it is detected that all the ribbons are used up, the other printing mechanism is used to perform unidirectional printing.

Therefore, according to the printing mechanism according to this embodiment,
During the forward movement of the carriage 14 in the right direction, the normal printing head 18 and the normal printing ink ribbon 2
4 performs normal printing in which characters are printed from the left side to the right side, and when the carriage 14 moves back to the left, the characters are printed by the reverse printing head 17 and the reverse printing ink ribbon 19. It is possible to perform reverse printing in which the image is printed from the right side to the left side. Also, if one of the ink ribbons is used up by performing back-and-forth printing in this way, use the other ink ribbon to perform unidirectional printing (either normal printing or reverse printing), and print both directions. By using up the ink ribbon, the period in which the ink ribbon is used up can be extended and the effort of replacing the ink ribbon can be saved.

〔effect〕

As explained above, according to the printing mechanism according to the present invention, two printing heads are provided, one for normal printing and one for reverse printing, and the direction in which the ink ribbon passes through the printing heads is different from the moving direction of the printing head. Since the direction is reversed, when the print head moves forward, the normal print head can print, and when the print head moves backward, the reverse print head can print. This increases the printing speed of the thermal transfer printer, thereby increasing the recording processing capacity of the thermal transfer printer.

In addition, in the present invention, two ribbon cassettes, one for normal printing and one for reverse printing, are used to perform reciprocating printing, which simplifies the transport route of the ink ribbon and reduces the running load placed on the ink ribbon. It is possible to make the ribbon smaller and thinner. Therefore, compared to the case of Reference 1, the present application requires less heat to melt the ink, and the power consumption can be reduced by that amount, which is economical.

Furthermore, in the present invention, since the two ribbon cassettes are arranged in parallel, there is no need for an elevating mechanism to move the cassettes each time the printing direction is changed. Reciprocating printing can be achieved with a simple mechanism.

[Brief explanation of drawings]

FIG. 1 is a plan view showing the printing mechanism according to the first embodiment of the present invention, FIG. 2 is a view taken from the direction of A in FIG. 1, and FIG. 3 is a plan view showing the printing mechanism according to the first embodiment of the present invention. 4 is an overall perspective view showing a conventional thermal transfer printer, FIG. 5 is a plan view showing a conventional printing mechanism in a thermal transfer printer, and FIG. 6 is a view taken from the direction of arrow B in FIG. The perspective view, FIG. 7, is an enlarged view showing the recording section of the print head. 2... Recording paper, 3... Platen, 14... Carriage, 15... Reverse printing ribbon cassette, 16
... Normal printing ribbon cassette, 17 ... Head for reverse printing, 18 ... Head for normal printing, 19 ... Ink ribbon for reverse printing, 24 ... Ink ribbon for normal printing.

Claims (1)

[Scope of Claims] 1. The ribbon cassettes are capable of independently moving forward and backward with respect to the platen, and are provided in correspondence with the two ribbon cassettes, one of which is pressed against the platen during leftward movement printing, and rightward movement printing. Two print heads, the other of which is sometimes pressed against the platen for printing, and two ribbon cassettes are provided, respectively, and during each printing, the ink ribbon passing through the print head is moved in the opposite direction to the direction of movement of the print head. 1. A reciprocating printing mechanism for a thermal transfer printer, comprising two ribbon drive shafts for respectively transporting and winding the ribbon.