JP3208255B2 - Printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer and, more particularly, to a printer having a characteristic paper guide portion.

Conventionally, in a printer as shown in FIG. 5 , a flat platen 1 made of a material such as rubber is provided, and a carriage 3 on which a print head 2 is mounted at a position facing the platen 1 is mounted on the platen. 1, a paper feed roller 4 and a pressure roller 5 are provided below the platen 1. A paper 6 is sandwiched between the paper feed roller 4 and the pressure roller 5 so that a print head is formed. 2 is carried. In addition, the platen 1
A paper discharge roller 7 for discharging the paper 6 after printing is disposed above the printer. Then, a paper guide 8 for guiding the paper 6 to the paper discharge roller 7 is formed in a V-shape, and one side of the paper guide 8 serves as a paper guide portion 9 so that the paper 6 moves in the outer peripheral direction of the paper discharge roller 7 It is inclined to be guided.

According to the printer having such a configuration, the print head 2 is pressed against the platen 1 via the paper 6 and the ink ribbon (not shown) conveyed by the paper feed roller 4 to perform printing. Do. After the printing, the paper feed roller is further rotated to convey the paper 6 so as to be wound around the paper discharge roller 7. On this occasion,
The sheet 6 is reliably guided to the holding portion of the sheet discharge roller 7 according to the inclination of the sheet guide section 9 of the sheet guide 8.

Further, in the case of color printing, when printing of one color is completed, the paper feed roller 4 and the paper discharge roller 7 are rotated in the reverse direction to reversely transport the paper 6 to an initial printing start position. Printing with the ink ribbon of the next color is repeated.

[0005]

However, according to the above-mentioned conventional printer, the paper guide 8 moves the paper guide section 9 to smoothly transport the transported paper 6 to the discharge roller 7. 6 are arranged to be inclined with respect to the direction in which they are transported. Therefore, the distance from the print head 2 to the paper pressing position by the paper guide 8 is large, and the leading end of the paper 6 flaps, which may adversely affect printing.

In order to suppress the slack between the paper discharge roller 7 and the paper feed roller 4 when the paper 6 is conveyed, the rotation amount of the paper discharge roller 7 is controlled by the rotation of the paper feed roller 4. Although slightly larger than the amount, when the paper 6 is reversely conveyed for color printing or the like, there is a problem that the paper 6 sags due to the difference in the rotation amount.

The present invention has been made in view of these points, and there is provided a printer which eliminates the influence of the rotation amount difference between the paper discharge roller 7 and the paper feed roller 4 and suppresses the fluttering of the paper 6 being conveyed. It is intended to provide.

[0008]

In order to achieve the above-mentioned object, a printer according to the present invention comprises a carriage having a print head which can be moved toward and away from a platen, and a paper for transporting a paper to a printing position by the print head. a feed roller, a paper discharge roller for discharging the the paper after printing is completed, use of the print position
With a canopy disposed downstream in the paper transport direction.
The canopy has a sheet contact portion that comes into contact with a sheet near a printing position during a printing operation and an outer periphery of the sheet discharging roller during sheet discharging.
Together with a paper discharge auxiliary section adjacent to the surface, the paper abutment or paper discharge auxiliary section of the canopy to the position of the paper
A drive source for moving the canopy is provided for selectively restricting the canopy to an operating position in response to the request .

[0009]

According to the present invention having the above-described structure, paper feeding
When the paper is transported to the print position by the print head by the rollers, and the carriage moves along the platen,
A print head presses the platen via the paper to perform printing. During this printing operation, the position of the canopy is regulated by the paper contact portion so as to press the paper, and the fluttering of the paper is suppressed. At this time, the paper is not affected by the paper discharge roller for discharging paper auxiliary section of the canopy is separated from the sheet discharging roller. On the other hand, at the time of paper discharge after printing is completed, the canopy moves the paper discharge auxiliary unit so as to be close to the paper discharge roller, and the paper discharge auxiliary unit of these canopies is moved.
The sheet is held between the sheet ejection rollers and discharged.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments shown in the drawings. It is to be noted that the same components as those of the conventional one described above are denoted by the same reference numerals in the drawings.

FIGS. 1 to 4 show a thermal transfer printer as an embodiment of the printer according to the present invention, in which a flat platen 1 made of an elastic material such as rubber is provided. Thermal head 2 at a position facing
Is provided so as to run along the platen 1 by a driving source (not shown). When the carriage 3 moves to the printing position along the platen 1, the thermal head 2 comes into pressure contact with the platen 1 via an ink ribbon (not shown) and the paper 6 to form a paper 6.
Will be printed. Below the pressure contact surface between the platen 1 and the thermal head 2, a paper feed roller 4 and a pressure contact roller 5 for sandwiching the paper 6 and transporting the paper 6 to the pressure contact surface are disposed in contact with each other. The paper feed roller 4 conveys the paper 6 in the direction of the paper discharge roller 7 and rotates in the reverse direction during color printing to feed the paper 6 back. Further, a paper discharge roller 7 is disposed at a position slightly separated laterally from an extension of an imaginary line connecting the contact surface and the pressure contact surface. The paper discharge roller 7 conveys the paper 6 after printing to a discharge port (not shown). On the other hand, near the paper discharge roller 7, a paper discharge auxiliary part 10 formed in a curved shape along the outer peripheral surface of the paper discharge roller 7, and a paper contact part 11 formed by a rotatable roller The paper contact portion 11 is retracted from a paper discharge path on the downstream side of the thermal head 2 by a drive source (not shown) such as a CSF motor. At the same time, the position where the discharge assisting portion 10 approaches the outer peripheral surface of the discharge roller 7, the position where the discharge assisting portion 10 separates from the outer peripheral surface of the discharge roller 7, and the position where the paper contact portion 11 is It is arranged to be rotatable between a position facing the paper discharge path on the downstream side of the head 2.

Therefore, when the canopy 12 is rotated in the direction of arrow A in FIG. 1, the paper contact portion 11 presses the paper 6 from one direction, stably prints, and transports the paper 6. In this case, the paper 6 is rotated to transport the paper 6 smoothly. At this time, since the paper discharge auxiliary unit 10 is separated from the paper discharge roller 7, the paper 6 is not wound around the paper discharge roller 7 provided at the conveyance destination, and the paper discharge It is not affected by the rotation of the paper roller 7.

When the canopy 12 is rotated in the direction of arrow B as shown in FIG. 2, the paper 6 enters the back of the canopy 12 from the gap between the canopy 12 and the carriage 3 and paper jam occurs. Further, as shown in FIG. 3, at the time of paper discharge, the curved surface portion of the paper discharge auxiliary unit 10 comes close to the outer periphery of the paper discharge roller 7, and the paper contact unit 11 Is inclined such that the sheet 6 is retracted from the sheet ejection path and is guided in the outer circumferential direction of the sheet ejection roller 7, and the sheet 6 is moved in accordance with the inclination in the vicinity of the sheet ejection roller 7 and the sheet ejection auxiliary unit 10. It is made to guide between.

Next, the operation of this embodiment having the above-described configuration will be described.

First, the thermal head 2 is pressed against the platen 1 via a paper 6 conveyed by a paper feed roller 4 and a pressure roller 5 while the carriage 3 is pressed.
Are printed along the platen, and printing is performed line by line.

On the other hand, when the paper 6 is conveyed at the beginning of printing, the canopy 12 is rotated to the position shown in FIG.
And prevents the paper from being jammed by entering the back of the canopy 12 through the gap between the canopy 12 and the canopy 12 and serves as a paper guide. When the paper 6 is transported to a position where there is no risk of entering the back of the canopy 12, the paper 6 is rotated to the position shown in FIG. 1 and the paper contact section 11 presses the paper 6 from one direction. In addition, the flapping of the paper 6 is suppressed, and the printing is performed satisfactorily. At this time, since the paper discharge auxiliary section 10 of the canopy 12 is separated from the paper discharge roller 7,
The paper 6 is not pinched between the paper discharge roller 7 and the paper discharge auxiliary unit 10, and is not affected by the paper discharge roller 7. Therefore, when the paper 6 is back-fed, the slack of the paper 6 caused by the rotation amount of the paper discharge roller 7 being larger than the rotation amount of the paper feed roller can be prevented.

Further, the when printing by the thermal head 2 to the sheet 6 is completed, in order to discharge the sheet 6, CF S motor the canopy 12 by a drive (not shown) or the like times in the direction of arrow B To move to the position shown in FIG. At this time, the sheet contact portion 11 is retracted from the sheet discharge path, and is inclined so as to guide the conveyed sheet 6 toward the outer periphery of the sheet discharge roller 7.
The paper discharge auxiliary unit 10 is close to the paper discharge roller 7 along the outer circumference. Therefore, the paper 6 is conveyed according to the inclination of the paper contact portion 11, is sandwiched between adjacent portions by the paper discharge roller 7 and the paper discharge auxiliary portion 10, and is discharged to a discharge port (not shown). .

According to such a configuration, during the printing operation or when the paper 6 is back-fed, it is not affected by the paper discharge force of the paper discharge roller 7, so that the paper feeding accuracy can be improved. In this case, there is no adverse effect due to the difference in the rotation amount between the paper discharge roller 7 and the paper feed roller. In other words, it is possible to prevent the slack of the paper 6 that occurs when the paper 6 is back-feeded as in the related art.

FIG. 4 (this embodiment) and FIG. 5 (conventional example)
As is clear from the comparison with the canopy 1 of this embodiment,
The second paper contact portion 11 presses the paper 6 in the vicinity of the printing position, so that the flapping of the paper 6 can be sufficiently suppressed and good printing can be performed. Accordingly, the top margin of the paper 6 can be reduced, and printing can be performed over a large area of the paper 6.

It should be noted that the present invention is not limited to the above-described embodiments, but can be modified as needed.

For example, a plurality of paper guides 8 may be provided between the platen 1 and the paper discharge roller 7 or the paper feed roller to assist in transporting the paper 6 in a predetermined direction.

[0022]

As described above, according to the present invention, since the influence of the paper discharge roller during the printing operation is eliminated, the paper produced by the difference in the feed amount between the paper discharge roller and the paper feed roller during reciprocal printing. it is possible to prevent the slack. Also, since the paper contact portion of the canopy presses the paper in the vicinity of the printing position, it is possible to suppress the fluttering of the paper and perform good printing, and further reduce the top margin of the paper and print over a large area of the paper. Can be.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a main part showing an embodiment during a printing operation of a printer of the present invention.

FIG. 2 is a schematic diagram illustrating a main part of an embodiment of the printer according to the present invention at the time of initial conveyance.

FIG. 3 is a schematic diagram illustrating a main part of a printer according to an embodiment of the present invention when paper is discharged.

FIG. 4 is a diagram illustrating a range of a top margin in the printer according to the embodiment of the invention.

FIG. 5 is a schematic configuration diagram of a main part showing a conventional printer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Platen 2 Thermal head 3 Carriage 4 Paper feed roller 5 Pressure contact roller 6 Paper 7 Discharge roller 10 Discharge auxiliary part 11 Paper contact part 12 Canopy

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B41J 13/00-13/32 B65H 29/52

Claims (1)

(57) [Claims] And 1. A carriage having a separable possible print head against the platen, a paper feed roller for conveying the sheet to the printing position by the print head, a paper discharge roller for discharging the the paper after printing is completed , Paper transport direction of the printing position
And a canopy disposed downstream.
Roh pin, along with a paper discharge auxiliary section adjacent to the outer peripheral surface of said discharge roller when discharging the paper abutting against the paper abutment on the paper at a printing position near the time of the printing operation, for the the canopy
A printer provided with a drive source for moving the canopy to selectively restrict a paper contact portion or a paper discharge auxiliary portion to an operation position according to a position of a sheet .