JPS62273874A - Serial printer - Google Patents

Abstract

PURPOSE:To prevent printing from occurring beyond the width of a paper, by providing a paper-detecting part and checking whether the paper is present at a printing position. CONSTITUTION:A printing-controlling part 7 supplied with printing data from a printing data receiving part 8 operates a printing head 2 to print on a paper 3 fed out from a paper feeding-out part 1 when the paper 3 is detected by a paper-detecting part 5. When the paper can not be detected by the part 5, the printing-controlling part 7 performs such a control that printing is not conducted and an error message PAPER SIZE OVER is displayed on an error display part 9. The paper-detecting part 5 judges that the paper 3 is present when both contacts 5a, 5b are out of contact with a platen 4, and it judges that the paper 3 is absent when at least one of the contacts 5a, 5b is in contact with the platen 4. When the impedance between the contacts 5a, 5b is high, they are regarded as out of contact with the platen 4. When any of the contacts 5a, 5b is grounded, it is regarded as in contact with the platen 4.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a serial printer, and particularly to a mechanism for prohibiting printing beyond the paper.

[Prior Art] Conventionally, this type of serial printer is composed of a paper sending unit, a print head, a print control unit, and a print data receiving unit, and prints by adjusting the paper width of the paper sending unit depending on the size of the paper. I was doing it.

[Problems to be solved] With the conventional serial printers mentioned above, the printable range changes depending on the width of the paper, so it is necessary to send data with care so that the print head travel range does not extend beyond the width of the paper. There is a drawback of 1.

[Means for Solving Problems] A serial printer of the present invention that solves the above-mentioned conventional problems includes: a paper sending unit that sends out paper; a print head that prints on the paper sent from the paper sending unit;
a print data reception unit that receives print data on the paper; a paper detection unit that detects whether or not the paper is present at the print position of the print head; and a paper detection unit that detects the paper when the paper is detected by the paper detection unit. a print control unit that sends print data from the print data reception unit to the print head and outputs an error display signal when the paper is not detected by the paper detection unit; and an error display from the print control unit. This configuration includes an error display section that receives a signal and displays an error indicating that the paper size is over.

[Example] Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram of a serial printer according to an embodiment of the present invention. In the figure, 1 is a paper feed section, 2 is a print head that prints on the paper 3 sent out from the paper feed section 1, 4 is a platen, and 5 is a paper detection section that detects the paper 3. Contacts 5a and 5b are card holder 6
is placed above. A detection signal of the paper 3 by the paper detection section 5 is sent to the print control section 7. The print control section 7 extracts the print data from the print data reception section 8, and when the paper detection section 5 detects the paper 3, the print control section 7 causes the print head 2 to print on the paper 3 sent out from the paper delivery section 1. Control. Further, if the paper detection section 5 cannot detect the paper, printing is not performed and the error display section 9 is controlled to display an error indicating that the paper size is over. The paper detection unit 5 determines that the paper 3 is present when both the contact 5a and the contact 5b are not in contact with the platen 4. If at least one of the contacts 5a and 5b is in contact with the platen 4, it is determined that there is no paper 3. Also, the contact point 5a.

Since the platen 4 is grounded, it is possible to determine whether the contact 5b is in contact with the platen 4 or not.
If b is high impedance, it is not in contact, and if it is grounded, it is considered to be in contact.

FIG. 2 shows an example of printing using the conventional method, in which the characters "0PQR" exceeding the paper width are printed on the platen 4.

Figure 3 shows an example of printing in this embodiment, with the characters "0PQ"
R'' is not printed, and the error display section 9 displays an error indicating that the paper size is over.

[Effects of the Invention] As explained above, the present invention prevents printing beyond the width of the paper by checking whether paper is present at the printing position and printing only when paper is present. This has the effect of preventing deterioration of the print head.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a serial printer according to an embodiment of the present invention, FIG. 2 is a diagram showing an example of printing by a conventional method, and FIG. 3 is a diagram showing an example of printing by the printer of FIG. 1. 1: Paper sending section 2: Print head 3: Paper 4 Nibraten 5: Paper detection section 5a, 5b: Contact 7: Print control section 8: Print data receiving section 9: Error display section

Claims (1)

[Claims] a paper sending unit that sends out paper; a print head that prints on the paper sent from the paper sending unit; a print data receiving unit that receives print data on the paper; a paper detection section that detects whether paper exists or not; and a paper detection section that sends print data from the print data reception section to the print head when the paper detection section detects the paper; The present invention is characterized by comprising a print control unit that outputs an error display signal when the paper is not detected, and an error display unit that receives the error display signal from the print control unit and displays an error indicating that the paper size is over. serial printer.