JPH04239678A - Printer - Google Patents

Abstract

PURPOSE:To always perform the printing at a correct position by a method wherein a sensor which detects a position of printing paper installed to a platen is provided and output of a printing data to a printing hammer is controlled. CONSTITUTION:When a printing data is sent, a control part moves a carriage 4 and makes a print hammer face successively from a most left end position to a right end of a platen 2. Thereby, a sensor detects a position of printing paper 1 and vary its output signal to a state of 'no paper' 'paper exists' 'no paper'. The output signal of the sensor is sent to a printing position regulation part of the control part. The printing position regulation part recognizes a position installed to the platen 2 of the printing paper 1 and a width of the printing paper 1 based on the output signal of the sensor. The control part outputs the printing data to the printing hammer 3 so that the previously inputted printing data is accurately printed on the printing paper 1 based on the position installed to the platen 2 of the printing paper 1 and the width of the printing paper 1.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing device that prints by mounting printing paper at any position on a cylindrical platen.

0002

[Prior Art] A conventional printing device that prints by attaching printing paper to an arbitrary position on a cylindrical platen has a carriage that reciprocates parallel to the axis of the platen, and a carriage mounted on the carriage that performs the printing operation. Although the printer is equipped with a printing section having a print hammer for performing the printing, it is usually not equipped with a detection mechanism specifically for detecting the width of the printing paper attached to the platen.

0003

[Problems to be Solved by the Invention] In the conventional printing device as described above, when loading printing paper, the operator places the printing paper in line with the specified insertion position of the printing paper on the printing device. There is a need to. For this reason, the operator must know the insertion position of the print paper specified on the printing device, and if the print paper is installed in the wrong position, the print paper may not be present for some print data. Since the printing operation is performed at a location where the printing is not performed, there is a drawback that not only the print data of that portion is not left on the printing paper, but also that the print hammer and platen that perform printing are damaged.

0004

[Means for Solving the Problems] A printing device of the present invention includes a cylindrical platen for mounting printing paper at an arbitrary position, a carriage that reciprocates in parallel with the axis of the platen, and a carriage mounted on the carriage. The printing device includes a printing unit having a print hammer that performs a printing operation, and a sensor that is mounted on the carriage and detects printing paper on the platen, and a sensor that performs a printing operation on the platen based on a signal from the sensor. A control section having a printing position adjustment section for adjusting the printing position is provided.

[0005]

Embodiments Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing the main parts of an embodiment of the present invention, FIG. 2 is a plan view showing the operation of the embodiment of FIG. 1, and FIG. 3 shows an output signal of the sensor of the embodiment of FIG. FIG. 4 is a block diagram showing the relationship among the sensor, print hammer, and control section of the embodiment of FIG. 1.

In FIG. 1, printing paper 1 can be mounted at any position on a cylindrical platen 2. As shown in FIG. The printing paper 1 mounted on the platen 2 is pressed against the platen 2 by a pinch roller (not shown), and is fed by the rotational movement of the platen 2. print hammer 3
is mounted on a carriage 4 and performs a printing operation on the printing paper 1 mounted on the platen 2 via an ink ribbon 7. The carriage 4 has two fixed shafts 5 and 6.
is used as a guide to perform reciprocating motion parallel to the axis of the platen. The carriage 4 is also equipped with a sensor (for example, a reflective photosensor) 8 for detecting the presence or absence of the printing paper 1 at a position near the print hammer 3 and facing the printing surface of the printing paper 1.

As shown in FIG. 4, the control section 9 has a print position adjustment section 10, which inputs the output signal of the sensor 8 and adjusts the mounting position of the printing paper 1. The printing position on the printing paper 1 by the print hammer 3 is adjusted based on the detection result.

Next, the operation of the printing apparatus constructed as described above will be explained with reference to FIGS. 2 and 3.

When print data is sent from a host device (not shown) to the printing device, the printing device inputs the print data to the control section 9. Before starting the printing operation, the control section 9 moves the carriage 4 to the left so that the print hammer 3 faces the leftmost position of the platen 2. FIG. 2(a) shows the state at this time. At this time, since the sensor 8 is located away from the printing paper 1, its output signal indicates a state of "no paper". Control unit 9
Then, the carriage 4 is moved to the right. sensor 8
detects the left edge of the printing paper 1 by this movement (state shown in FIG. 2(b)) and changes its output signal to the "paper present" state (reference numeral A in FIG. 3). The control unit 9 continues to move the carriage 4 to the right. The sensor 8 thereby detects the right edge of the printing paper 1 and changes its output signal to the "no paper" state (reference numeral B in FIG. 3). The output signal of the sensor 8 is sent to the print position adjustment section 10 of the control section 9, and the print position adjustment section 10 adjusts the mounting position of the print paper 1 relative to the platen 2 and the width of the print paper 1 based on the output signal of the sensor 8. The controller 9 then controls the print hammer 3 to correctly print the previously inputted print data on the print paper 1 based on the mounting position of the print paper 1 relative to the platen 2 and the width of the print paper 1. Output data.

[0011]

As explained above, in the printing device of the present invention, a sensor for detecting the position of printing paper attached to a cylindrical platen is mounted on a carriage that is mounted with a print hammer and moves back and forth in parallel with the axis of the platen. By controlling the output of print data to the print hammer so that the print data is printed correctly on the print paper in a control unit having a print position adjustment unit based on the output signal, the print data can be printed at any position on the platen. It has the effect of being able to always print in the correct position on the paper.
Therefore, it is possible to prevent the print data from being left on the print paper due to a printing operation performed in a place where there is no print paper, and also to prevent damage to the print hammer or platen.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the main parts of an embodiment of the present invention.

FIG. 2 is a plan view showing the operation of the embodiment of FIG. 1;

FIG. 3 is a waveform diagram showing an output signal of the sensor of the embodiment of FIG. 1;

FIG. 4 is a block diagram showing the relationship among a sensor, a print hammer, and a control unit in the embodiment of FIG. 1;

[Explanation of symbols]

1 Printing paper 2 Platen 3 Print hammer 4 Carriage 5 Fixed axis 6 Fixed axis 7 Ink ribbon 8 Sensor 9 Control section 10 Print position adjustment section

Claims (1)

[Claims] 1. A printing section comprising: a cylindrical platen on which printing paper is mounted at an arbitrary position; a carriage that reciprocates in parallel with the axis of the platen; and a print hammer mounted on the carriage to perform a printing operation. A printing device comprising: a sensor mounted on the carriage to detect printing paper on the platen; and a print position adjustment section that adjusts a position at which a printing operation is performed with respect to the platen based on a signal from the sensor. A printing device characterized by comprising a control section.