JP3104546B2 - Thermal recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal recording apparatus for printing on recording paper using a thermal head.

[0002]

2. Description of the Related Art In recent years, with the spread of personal computers and the like, printers, which are peripheral devices thereof, have become widespread. In particular, demand for thermal recording apparatuses has been increasing.

[0003] A conventional thermal recording apparatus will be described below. FIG. 6A is a plan view of a conventional thermal recording apparatus, and FIG.
Is a front view. 6, reference numeral 1 denotes a recording paper, 2 denotes a thermal head for printing on the recording paper 1 by heat generation,
Is a platen roller rotatably supported, 14 is a paper transport unit that holds the leading end of the recording paper 1 and reciprocates, and 7 is an ink sheet. The thermal head 2 can press and separate the ink sheet 7 and the recording paper 1 with respect to the platen roller 3 by a drive system (not shown), and the ink sheet 7 is properly rotated with the progress of printing by a rotary drive system (not shown). It is configured to be wound up by an amount.
The sheet holding portion A of the sheet conveying means 14 is pressed by the force of a spring (not shown) and can hold the recording sheet 1. The sheet holding portion A is pressed against the spring force by opening means (not shown). Can be opened. In addition, the ink sheet 7 in the plan view (a) is omitted.

The operation of the conventional thermal recording apparatus configured as described above will be described below. First, the thermal head 2 and the platen roller 3 are separated from each other,
7 is fed by a sheet feeding mechanism (not shown), the thermal head 2 presses the ink sheet 7 and the recording sheet 1 against the platen roller 3 as shown in FIG. Next, FIG.
As shown in FIG. 6B, the sheet holding unit A of the sheet conveying unit 14 is opened and moves in the direction B in the drawing, and the sheet holding unit A is closed. Is held. In the state shown in FIG. 6, the paper transporting means 14 moves in the direction C in the drawing, and the thermal head 2 generates heat to transfer the ink of the ink sheet 7 to the recording paper 1. When printing is completed as shown in FIG. 7C, the thermal head 2 is separated from the platen roller 3 and
The recording sheet 1 is discharged by a discharge mechanism (not shown) when the sheet holding portion A is opened. In the conventional thermal recording apparatus, printing is performed by the above operation.

[0005]

However, in the above-described conventional configuration, since the leading end of the recording sheet 1 is not regulated by any component, the height of the leading end of the recording sheet 1 depends on the curl state of the leading end. Variations increase. Therefore, if the leading end of the recording sheet 1 is curled more than the opening of the sheet holding section A, the sheet holding operation becomes impossible. In the conventional configuration, this variation is absorbed, and the leading end of the recording paper 1 is reliably moved to the paper holding section A of the paper transporting means 14.
Therefore, it is necessary to secure a sufficient opening amount of the sheet holding portion A so that the sheet holding portion A is inserted into the sheet holding portion. As a result, there is a problem that the sheet conveying means 14 becomes large because the opening amount becomes large, and the opening means and its driving source also become large at the same time. Even if the opening amount of the sheet holding unit A is larger than the curl of the leading end of the recording sheet 1 and the recording sheet 1 can be inserted into the sheet holding unit A of the sheet conveying means 14, the sheet holding operation is performed with the leading end curled. For this reason, the leading edge of the recording sheet 1 is creased or wrinkled, the holding accuracy of the recording sheet 1 with respect to the sheet conveying means 14 is deteriorated, and as a result, the printing accuracy of the recording sheet 1 is deteriorated. .

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems. The paper conveying means, the opening means, and the driving source thereof are miniaturized, and the leading end of the recording paper is not creased or wrinkled. It is another object of the present invention to provide a highly reliable thermal recording apparatus capable of improving the accuracy of holding a recording sheet with respect to a sheet transport unit and, as a result, improving the printing accuracy of the recording sheet.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned conventional problems, a thermal recording apparatus according to the present invention includes a front end and a rear end of a recording sheet at a position where a sheet holding operation is performed by a sheet conveying means. The sheet holding means includes a sheet holding means capable of positioning the leading end of the recording sheet at a specific position, and a position detecting means located near the sheet holding means and capable of detecting the positions of the recording sheet and the sheet conveying means.

[0008]

According to this configuration, when the sheet conveying means performs the sheet holding operation, even if the leading end of the recording sheet is curled, the recording sheet is pinched from both the front and back sides of the recording sheet and positioned at a specific position. can do. As a result, the opening amount of the sheet holding section can be small, and the sheet conveying means can be downsized, and at the same time, the opening means and its driving source can be downsized. Also, there is no fold or wrinkle at the leading edge of the recording paper,
Further, the accuracy of holding the recording paper with respect to the paper conveying means is improved, and as a result, the printing accuracy of the recording paper can be improved, and a highly reliable thermal recording apparatus can be realized.

[0009]

Embodiments of the present invention will be described below. FIG. 1A is a plan view of a thermal recording apparatus according to an embodiment of the present invention,
(B) is a front view. In FIG. 1, 1 is a recording paper,
Reference numeral 2 denotes a thermal head for performing printing on the recording paper 1 by heat generation, 3 denotes a platen roller rotatably supported, 4 denotes a paper transport means for holding the leading end of the recording paper 1 and reciprocating, 5
Paper holding means capable of holding the leading end of the recording sheet 1 at a position where the sheet holding operation is performed by the sheet transporting means from both front and back sides and positioning the leading end of the recording sheet 1 at a specific position;
Reference numeral 6 denotes an optical sensor serving as a position detecting unit capable of detecting the positions of the recording sheet 1 and the sheet conveying unit 4, and reference numeral 7 denotes an ink sheet.
The thermal head 2 can press and separate the ink sheet 7 and the recording paper 1 with respect to the platen roller 3 by a drive system (not shown), and the ink sheet 7 is properly rotated with the progress of printing by a rotary drive system (not shown). It is configured to be wound up by an amount. The sheet holding portion A of the sheet transporting means 4 is pressed by the force of a spring (not shown) and can hold the recording sheet 1, and the sheet holding portion A is pressed against the spring force by opening means (not shown). Can be opened. The sheet holding means 5 is divided into an upper part and a lower part. The lower part is fixed at a specific height, and the upper part is moved in the vertical direction by a control system (not shown) to change the gap between the upper part and the lower part, thereby holding the recording paper. Can be pinched and released. In addition, the ink sheet 7 in the plan view (a) is omitted.

The operation of the embodiment of the present invention configured as described above will be described below. First, after the thermal head 2 and the platen roller 3 are separated from each other and the recording paper 1 is fed by a paper feed mechanism (not shown),
As shown in (a), the thermal head 2 presses the ink sheet 7 and the recording paper 1 against the platen roller 3. Here, the upper portion of the sheet holding means 5 presses the leading end of the recording sheet 1 from the recording surface side to perform positioning as shown in FIG. 2B. Next, the sheet holding unit A of the sheet conveying unit 4 is opened and moves in the direction B in the drawing, and the sheet holding unit A is closed.
As described above, the leading end of the recording sheet 1 is held by the sheet conveying means 4, and the upper portion of the sheet holding means 5 is separated from the recording sheet 1. In this sheet holding operation, since the sheet holding means 5 positions the leading end of the curled recording sheet 1 at a specific height, the variation in the height of the leading end of the recording sheet 1 is reduced, and the sheet holding section A of the sheet conveying means 4 is reduced. The opening amount of the recording paper 1 can be reduced, and the leading end of the recording paper 1 is not broken or wrinkled. In addition, the holding accuracy of the recording paper 1 with respect to the paper transporting means 4 is improved. In the state shown in FIG. 1, the paper transporting means 4 moves in the direction C in the drawing, and the thermal head 2 generates heat to transfer the ink of the ink sheet 7 to the recording paper 1. FIG.
When printing is completed as shown in (c), the thermal head 2 is separated from the platen roller 3, the sheet holding portion A of the sheet conveying means 4 is opened, and the recording sheet 1 is discharged by a sheet discharging mechanism (not shown). . Printing is performed by the above operation.

Here, in the paper feeding operation shown in FIG. 2A, the paper feeding operation is terminated after the leading end of the recording paper 1 has passed through the optical sensor 6 and has been fed by a certain amount. FIG. 1 (b)
When the paper transporting means 4 moves, the paper transporting means 4 is stopped at a position which has passed the optical sensor 6 and has been moved by a certain amount. As described above, since the optical sensor 6 near the leading end of the recording sheet 1 and the position where the sheet conveying means 4 is stopped is detected, the stopping accuracy of the recording sheet 1 and the sheet conveying means 4 is improved. Accordingly, the accuracy of holding the recording paper 1 with respect to the paper transporting means 4 is further improved, and as a result, the printing accuracy of the recording paper 1 can be further improved. Further, as shown in FIG. 3, by passing the recording paper 1 in a state where the gap of the paper nipping means 4 is slightly wider than that of nipping the recording paper 1, variation in the height of the leading end of the recording paper 1 is reduced. In addition, the accuracy of position detection by the optical sensor 6 can be improved. By forming the sheet holding means as shown in FIG. 4, it is possible to take measures against jamming in the sheet feeding operation and the sheet conveying operation.

In this embodiment, the lower portion of the sheet holding means is fixed and the upper portion is moved. However, even if the upper portion is fixed and the lower portion is moved, both are moved. The same effect can be obtained even if both are fixed and the recording paper is guided to the paper holding means as shown in FIG.

In this embodiment, a thermal transfer type thermal recording apparatus for transferring ink on an ink sheet to recording paper has been described. However, a thermal type thermal recording apparatus for printing on thermal recording paper without using an ink sheet, It goes without saying that the same configuration can be applied to a thermal recording apparatus that performs color printing by repeating the above printing operation several times.

[0014]

As described above, according to the present invention, the leading end of the recording sheet at the position where the sheet holding operation is performed by the sheet conveying means is held from both the front and back sides, and the leading end of the recording sheet can be positioned at a specific position. Paper holding means, and a position detecting means provided near the paper holding means and capable of detecting the positions of the recording paper and the paper conveying means, whereby the paper conveying means, the opening means and the driving source thereof are miniaturized, The end of the recording paper is not creased or wrinkled, and the holding accuracy of the recording paper with respect to the paper transport means is improved. As a result, the printing accuracy with respect to the recording paper can be improved. The device can be realized, and its practical effect is great.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of a thermal recording apparatus according to an embodiment of the present invention.

FIG. 2 is a front view for explaining the operation of the thermal recording apparatus according to the embodiment of the present invention.

FIG. 3 is a front view for explaining the thermal recording apparatus according to the embodiment of the present invention.

FIG. 4 is a front view for explaining the thermal recording apparatus according to the embodiment of the present invention.

FIG. 5 is a front view for explaining the thermal recording apparatus according to the embodiment of the present invention.

FIG. 6 is a diagram for explaining a configuration of a conventional thermal recording apparatus.

FIG. 7 is a front view for explaining the operation of a conventional thermal recording apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Recording paper 2 Thermal head 3 Platen roller 4 Paper conveyance means 5 Paper holding means 6 Position detection means 7 Ink sheet

Continuing on the front page (72) Inventor Taichi Ito 1006 Kadoma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. 72) Inventor Fumihiro Ito 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Osamu Mogami 1006 Odaka Kazuma Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. JP-A-4-37567 (JP, A) JP-A-2-235672 (JP, A) JP-A-6-8492 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41J 2 / 32-2/325 B41J 13/22 B41J 11/00

Claims (2)

(57) [Claims] A thermal head for performing printing on recording paper by heat generation, a platen roller rotatably supported,
A sheet transporting unit that holds the leading end of the recording sheet and reciprocates, and the leading end of the recording sheet that is held at the position where a sheet holding operation is performed by the sheet transporting unit from both the front and back. A sheet holding means capable of positioning the sheet at a specific position. 2. A thermal recording apparatus according to claim 1, further comprising a position detecting means located near the sheet holding means and capable of detecting the positions of the recording sheet and the sheet conveying means.