JP2000094786A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To print on various kinds of recording papers with different numbers of superimposition by the optimum printing mode by reading a mark showing the number of superimposed recording paper sheets provided on the recording papers inserted from a recording paper inserting opening by a reading means, and switching the printing mode according to the reading result. SOLUTION: After turning on the power source, a recording paper 6 is inserted from a recording paper inserting opening 7. When the tip of the recording paper 6 reaches at the position of a transmission type sensor 9, the recording paper 6 is detected by the transmission type sensor 9. When the transmission type sensor 9 detects the recording paper 6, a reflection type sensor 12 is turned on so as to start the reading operation of a mark 11 by the reflection type sensor 12. The reading operation is executed until the mark 11 is read out, or the tip portion of the recording paper 6 reaches at the printing position so that a conveying motor is stopped. In the case the mark 11 is read out, the printing mode is switched according to the number of the black lines in the mark 11 so that a printing mode switching means is driven.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording sheet having two or more superposed sheets (for example, a copy slip) and a recording sheet having one superposed sheet (i.e., 1 sheet).
The present invention relates to a printer capable of performing printing with improved print quality on a normal recording paper made of a sheet of paper.

[0002]

2. Description of the Related Art Conventionally, in a thermal printer capable of performing printing on a recording sheet having two or more superposed sheets and a recording sheet having one superposed sheet, such a recording paper is used. Printing such as the application time and application timing of the thermal head, the transport speed of the recording paper at the time of printing, and the pressing force of the thermal head against the platen, so that printing with good print quality can be performed even when the number of superposed papers is different. The mode can be adjusted. For example, when printing is performed on recording paper having one superimposed sheet, the application time of the thermal head is shortened, the transport speed of the recording paper is increased, and the pressing force of the thermal head is reduced. The print mode is switched to. On the other hand, when printing is performed on a plurality of recording papers in which the number of superposed papers is plural, the application time of the thermal head becomes longer, the conveyance speed of the recording paper becomes lower, and the pressing force of the thermal head becomes stronger. The print mode is switched to.

The above-described print mode switching is manually performed by an operator of the thermal printer in accordance with the number of sheets to be superimposed on each recording sheet.

[0004]

It is very complicated for the operator to manually switch the print mode of the thermal printer every time printing is performed. In addition, when the print mode is switched by a manual operation, the print mode may be erroneously changed, and the print quality is degraded by erroneously switching the print mode.

Accordingly, the present invention can automatically switch the print mode in accordance with the number of sheets to be superimposed on each recording sheet, eliminating the need for the printer operator to switch the print mode manually. It is another object of the present invention to provide a printer capable of improving the printing quality of each recording sheet.

[0006]

According to a first aspect of the present invention, there is provided a printer comprising: a platen; a print head pressed against an outer peripheral surface of the platen; and a recording paper inserted from a recording paper insertion slot. Conveying means for conveying to a printing position pressed by the platen, reading means for reading a mark provided on the recording paper until the recording paper is conveyed to a predetermined position, the mark indicating the number of superposed sheets of the recording paper; Print mode switching means for switching the print mode to a print mode corresponding to the number of sheets of recording paper to be superimposed according to the result of reading by the reading means.

Accordingly, the recording paper inserted from the recording paper insertion slot is conveyed to a predetermined position by the conveying means, and a mark indicating the number of superposed sheets of the recording paper provided on the recording paper during the conveyance is read by the reading means. Read. The print mode for printing on the recording paper is switched by the print mode switching means in accordance with the reading result of the reading means,
Printing is performed on the recording paper in a print mode suitable for the number of sheets of recording paper to be superimposed. For this reason, even when the number of superposed sheets of each recording sheet is different, printing is performed in the most suitable print mode on each recording sheet, and the printing quality is improved.

According to a second aspect of the present invention, there is provided the printer according to the first aspect, wherein the reading means cannot read a mark on the recording sheet before the recording sheet is conveyed to a predetermined position. The printing mode switching means switches the printing mode to a printing mode corresponding to a recording sheet having one superimposed sheet.

Accordingly, for a recording sheet having one superposed sheet, that is, a recording sheet composed of one sheet,
There is no need to provide a mark indicating the number of sheets of recording paper to be overlaid. In addition, printing can be performed on various types of recording paper made of one sheet on which no mark is provided by using a print mode suitable for the recording paper, and print quality can be improved.

According to a third aspect of the present invention, in the printer according to the first or second aspect of the present invention, there is provided a pressing mechanism for pressing the print head against the platen, and the print mode switching means is read by the reading means. The pressing force of the pressing mechanism is switched according to the number of sheets of recording paper to be overlaid.

Therefore, the pressing force of the print head against the platen is switched according to the number of sheets of recording paper to be superposed. By switching this pressing force so as to increase as the number of superposed sheets of recording paper increases, the print quality can be improved in various types of recording paper having different numbers of superposed sheets.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing the entire structure of the thermal printer, and FIG. 2 is a vertical sectional side view thereof. In this thermal printer, a platen 2 and a thermal head 3 as a print head are provided in a main body case 1. The thermal head 3 is rotatably provided around a support shaft 4,
The torsion spring 5 urges the outer peripheral surface of the platen 2 in a direction of pressing the outer peripheral surface.

A recording paper insertion slot 7 into which the recording paper 6 is inserted is formed in the front part of the main body case 1, and the recording paper is directed from the recording paper insertion opening 7 to a printing position where the thermal head 3 is pressed against the platen 2. A transfer path 8 through which the transfer sheet 6 is transferred is formed. A transmissive sensor 9 for detecting that the recording paper 6 has been inserted through the recording paper insertion port 7 and a recording paper 6 inserted through the recording paper insertion port 7 are conveyed to the printing position on the transport path 8. A pull-in roller 10 as a conveying unit and a reflection type sensor 12 as a reading unit for reading a mark 11 printed on an edge of a front surface of the recording paper 6 in the conveying direction are arranged.

A transport motor 13 for rotating and driving the platen 2 and the pull-in roller 10 is provided on an outer peripheral portion of the main body case 1.
And a pressing force switching motor 14 for switching the pressing force with which the thermal head 3 is pressed against the platen 2.

Here, in this thermal printer, printing is performed on a normal recording sheet 6 made of one sheet and on a copy type recording sheet 6 in which two or more sheets are overlapped.
In the recording paper 6 on which two or more papers are superimposed, a mark 11 indicating the number of superimposed papers is printed on the surface side edge of the recording paper 6 and outside the printing area 6a of the recording paper 6. (See FIGS. 1 and 3). These FIGS. 1 and 3
Indicates recording paper 6 in which two sheets are superimposed,
The mark 11 is formed by two black lines drawn in a direction orthogonal to the transport direction of the recording paper 6. If the number of superposed sheets is three, the mark 11 consisting of three black lines is printed, and if the number of superposed sheets is four, four marks are printed. A mark 11 consisting of a black line is printed. In the case of the recording paper 6 made of one sheet, the mark 11 is not printed.

FIGS. 5 to 7 show the structure of a pressing mechanism 15 for pressing the thermal head 3 against the platen 2. FIG.
The pressing mechanism 15 includes a pressing force switching motor 14, a gear 16 fixed to a motor shaft of the pressing force switching motor 14, and a gear 1.
The idle gear 18 meshed with the gear 6 and the gear 17, a cam 19 rotating integrally with the gear 17, one end of which is rotatably connected to the cam 19, and a substantially central portion is rotatably mounted around the support shaft 4. Pair of arms 20, pair of arms 20
Shaft 21 and stopper projection 2 for restricting rotation of arm 21 from a predetermined position in a counterclockwise direction.
2. The torsion spring 5 is wound around the support shaft 4 and has one end locked to the connection shaft 21 and the other end locked to the thermal head 3.

FIG. 6 shows a state in which the pressing force of the thermal head 3 against the platen 2 is the smallest. FIG. 7 shows a state in which the cam 19 is rotated in the direction of arrow A from the position shown in FIG. 6 through the gears 16 and 17 and the idle gear 18 by the driving of the pressing force switching motor 14, and the torsion angle of the torsion spring 5 is shown. Is the smallest, and the platen 2 of the thermal head 3
Pressing force is the strongest. The switching of the pressing force of the thermal head 3 against the platen 2 can be performed steplessly by appropriately adjusting the rotational position of the cam 19.

A projection 19a is formed on a part of the outer peripheral portion of the cam 19. The projection 19a comes into contact with the thermal head 3 while the cam 19 rotates from the position shown in FIG. 6 to the position shown in FIG. 7, and temporarily separates the thermal head 3 from the platen 2.

Next, the thermal printer includes a transmission type sensor 9, a reflection type sensor 12, and a transport motor 13
And a control unit (not shown) to which the pressing force switching motor 14 is connected. Further, the thermal printer is provided with print mode switching means for automatically switching the print mode according to the number of sheets of recording paper 6 to be superimposed. This print mode switching means will be described with reference to the flowchart of FIG. 8 and the timing chart of FIG.

After the power switch is turned on, the recording paper 6 is inserted from the recording paper insertion slot 7, and when the leading end of the recording paper 6 reaches the position of the transmission sensor 9, the recording paper 6 is moved by the transmission sensor 9. It is detected (step S1). When the transmission type sensor 9 detects the recording paper 6, the reflection type sensor 12 is turned on (step S2), and the mark 11 is read by the reflection type sensor 12 (step S3). The reading of the mark 11 is performed until the mark 11 is actually read.
Alternatively, the process is performed until the leading end of the recording paper 6 reaches the printing position and the transport motor 13 stops (step S4).

FIG. 4 is a timing chart showing an output signal when the reflection type sensor 12 reads the mark 11.
(A) is a case where the number of superposed sheets is one recording sheet 6;
(B) is a case where the number of sheets of superimposed paper is two recording papers 6,
(C) shows an output signal in the case where the number of superposed sheets is n of recording paper 6. The transmission type sensor 12 outputs a black level signal immediately after being turned on. When the leading end of the recording paper 6 reaches a position facing the transmission type sensor 12, the white level (the ground color of the recording paper 6) is output. Level) signal. After the white level signal is output, the mark 1
A signal of a black level is output by facing 1 (the number of black lines). In the case of (a), the signal of the black level is output 0 times, in the case of (b), twice, and in the case of (c), n times.

By the time the transport motor 13 stops, the mark 1
If the reading of the recording paper 6 cannot be performed, it is determined that the recording paper 6 is one recording paper 6 and the printing mode is changed to the printing mode corresponding to the one recording paper 6. Switching is performed (step S5). Here, the print mode switching means is executed.

If the mark 11 has been read, the mode is switched to a print mode corresponding to the mark 11 (the number of black lines) (step S6). Here, the print mode switching means is executed.

Here, the switching of the printing mode is to switch the application time and application timing of the thermal head 3, the transport speed of the recording paper 6 during printing, and the pressing force of the thermal head 3 against the platen 2. Specifically, when the number of superposed sheets is one recording sheet 6,
The application time of the thermal head 3 becomes the shortest, and the recording paper 6
Is the highest, and the pressing force of the thermal head 3 is the weakest. As the number of sheets of the recording paper 6 to be superimposed increases, the application time of the thermal head 3 increases, the transport speed of the recording paper 6 decreases, and the pressing force of the thermal head 3 increases.

In such a configuration, when the recording paper 6 is inserted from the recording paper insertion slot 7, the mark 11 indicating the number of superposed sheets of the recording paper 6 printed on the recording paper 6 is read by the reflection sensor 12. The printing mode is switched according to the reading result. For this reason, printing on the recording paper 6 can be performed in an optimal printing mode according to the number of sheets of the recording paper 6 to be superimposed, and the printing quality can be improved. In addition, the trouble of the operator manually switching to the print mode corresponding to the number of sheets of recording paper 6 to be superimposed is eliminated.

If the transmission type sensor 9 cannot read the mark 11, the mode is switched to a print mode suitable for printing on the recording paper 6 having one superimposed sheet. For this reason, when the number of superposed sheets is one recording paper 6, the mark 1
The trouble of printing 1 is not required. In addition, high-quality printing can be performed on various types of recording paper 6 made of one sheet.

In the present embodiment, a thermal printer has been described as an example of a printer to which the present invention is applied. However, the present invention can be applied to a dot impact printer.

In this embodiment, the recording paper 6
In the above description, the mark 11 is printed as an example of the mark 11 provided. However, the mark 11 may be formed by attaching a seal or by forming a hole or notch.

[0029]

According to the printer of the first aspect of the present invention, the reading means reads the mark provided on the recording paper inserted from the recording paper insertion slot and indicating the number of superposed sheets of the recording paper, and reads the mark. Since the print mode for the recording paper is switched by the print mode switching means according to the result, it is possible to eliminate the trouble that the printer operator manually switches to the print mode corresponding to the number of sheets of recording paper to be superimposed. In addition, printing can be performed in an optimum print mode on various types of recording paper having different numbers of superposed papers, and the print quality on each recording paper can be improved.

According to the printer of the second aspect of the present invention,
In the printer according to the first aspect of the present invention, if the reading means cannot read the mark on the recording paper before the recording paper is conveyed to a predetermined position, the printing mode switching means sets the number of superimposed paper sheets to be smaller. Since the print mode is switched to the print mode corresponding to one sheet of recording paper, the number of sheets of superimposed paper indicates the number of sheets of superposed paper for a single sheet of recording paper, that is, a single sheet of recording paper. It is not necessary to provide a mark. In addition, printing can be performed on various types of recording paper made of one sheet in a print mode suitable for the recording paper, and the printing quality can be improved.

According to the printer of the third aspect of the present invention,
3. The printer according to claim 1, further comprising a pressing mechanism for pressing the print head against the platen, wherein the print mode switching means presses the pressing mechanism in accordance with the number of sheets of recording paper read by the reading means. When the number of sheets of recording paper is large, the pressing force is increased, and when the number of sheets of recording paper is small, the pressing force is reduced. The printing quality can be improved on different types of recording paper.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a thermal printer according to an embodiment of the present invention.

FIG. 2 is a vertical sectional side view showing the thermal printer.

FIG. 3 is a plan view showing recording paper on which marks are printed.

FIG. 4 is a timing chart showing an output signal at the time of reading a mark of the reflection type sensor.

FIG. 5 is a perspective view showing a pressing mechanism.

FIG. 6 is a side view showing the pressing mechanism in a state where the pressing force is minimized.

FIG. 7 is a side view showing the pressing mechanism in a state where the pressing force is maximized.

FIG. 8 is a flowchart illustrating a mode switching unit.

[Description of Signs] 2 Platen 3 Printhead 6 Recording paper 7 Recording paper insertion port 10 Conveying means 11 Mark 12 Reading means 15 Pressing mechanism

Claims (3)

[Claims] 1. A platen, a print head pressed against the outer peripheral surface of the platen, and a conveying means for conveying recording paper inserted from a recording paper insertion port to a printing position where the print head is pressed against the platen. Reading means for reading a mark provided on the recording paper until the recording paper is conveyed to a predetermined position, the mark indicating the number of superposed sheets of the recording paper; and recording a print mode in accordance with a result of reading by the reading means. A printer having print mode switching means for switching to a print mode corresponding to the number of sheets of paper to be overlaid. 2. The printing mode switching means, if the reading means cannot read a mark on the recording paper until the recording paper is conveyed to a predetermined position, the printing mode switching means sets the number of superposed sheets to one. 2. The printer according to claim 1, wherein the printing mode is switched to a printing mode corresponding to the recording paper. 3. A printing mechanism comprising a pressing mechanism for pressing the print head against the platen, wherein the printing mode switching means switches the pressing force of the pressing mechanism in accordance with the number of sheets of recording paper read by the reading means. Claim 1
Or the printer according to 2.