JPS60139460A - Serial type dot printer - Google Patents

Abstract

PURPOSE:To construct the serial type dot printer of small size, low price and high reliability, which can carry out high density printing, by a method wherein drive means are alternately arranged and printing pins are arranged on an inclined one straight line. CONSTITUTION:Printing pins 17... are arranged on an inclined one straight line and drive apparatus 15 driving those printing pins 17... are vertically alternately arranged. Thereby, the vertical pitch between the printing pins 17, 17 is lessened and the interval between the dots 23... composing a letter can be narrowed down. Further, spaces for the drive apparatus 15... can be secured. Therefore, high density printing can be carried out with the titled printer of small size, low price and high reliability.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a serial type dot printer that prints characters in a dot matrix structure.

[Technical background of the invention and its problems]

Conventionally, in the dot matrix and printers used for output from word processors, etc., one character is printed in 4i 24
24-dot printers The 24-dot printer made up of IJ boxes has been the mainstream, but recently there has been an increasing demand for higher densities to bring the quality of printing, such as kanji output, even closer to that of printed characters.

Therefore, it is desired to produce a high-density printer in which the character size is the same as before and each character is composed of 24 x 24 dot matrices or more. , it was difficult to achieve high density with dot-type line printers for the following reasons.In other words, with wire-dot-type serial printers,
It has a structure in which 24 printing wires are concentrated in a very narrow space on the printing surface.

For this reason, the printing wire must be bent using a guide or the like from the joint surface between the driving section and the printing wire arranged in a circumferential manner to the printing surface. In a very narrow space, the printing wire must be attached to the drive part using methods such as brazing to avoid contact with adjacent wires. Therefore, in order to increase the printing dot density without changing the character size, it is necessary to make the printing wire thinner. It is easy to break and the reliability is reduced. Furthermore, it is technically difficult to join a large number of printing wires and drive units in a single slot with a very narrow joining surface.

As described above, manufacturing a print head capable of high-density printing has been difficult due to reliability, manufacturability, etc.

Therefore, a dot-type line printer was developed that prints without using a printing wire. In this printer, short printing pins attached to the print hammer are arranged at equal intervals over a length equal to the width of the print medium in a straight line vcl perpendicular to the moving direction of the print medium. A one-dot line is printed on the printing medium by swinging the hammer base to which the hammer base is attached by the length of the pitch to the adjacent printing bin, and driving each hammer while keeping the timing υ. Then, after printing one dot line, the printing medium is moved by one dot pitch in a direction perpendicular to the dot line, and the next one dot line is printed by driving the hammer in the same manner. In this type of printer, short printing pins can be used instead of wires, so in order to increase the density, it is sufficient to simply reduce the diameter of the tip of the printing bottle. However, this type of printer requires a large number of hammers, so a large-capacity power source is required to drive the hammers, and a large special drive is required to swing the hammer base to which the hammers are attached. Since it also requires equipment, the printer has the disadvantage of being expensive and large.

[Purpose of the invention]

This invention was made based on the above circumstances, and its purpose is to provide a serial type dot printer that is small, inexpensive, has a high axis multiplier, and is capable of high-density printing. .

[Summary of the invention]

In order to achieve the above object, the present invention prints a character consisting of a combination of m×n dots in the vertical and horizontal directions on the printing medium while scanning the printing medium in a direction perpendicular to the direction of movement of the printing medium. The serial type dot printer includes a printing mechanism for printing on the printing medium, and a moving means for reciprocating the printing mechanism by a width greater than the printing width of the printing medium, and the printing mechanism is configured to print at a constant rate in the scanning direction. m print bins arranged on a straight line with an inclination and mfWs that correspond to the print bins V of these m IVJs and are arranged alternately with the straight line as a boundary and drive the print bins; The invention is characterized in that it is configured by providing means.

〔Effect of the invention〕

According to the present invention, by alternating the driving means, the printing mechanism becomes smaller in the width direction of the printing medium.
The printing mechanism is about the same size as a conventional wire dot type serial printer, and by arranging the print bin on a single inclined straight line, printing can be performed with the same carriage movement as a conventional wire dot type serial printer. Accordingly, it is possible to provide a serial dot printer that is small, inexpensive, highly reliable, and capable of high-density printing.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. In FIGS. 1 and 2, 1 indicates a U-shape in which the printing paper (printing medium) P is tightly wrapped around a portion of the paper by being rotationally driven by the first motor 5, and is fed in a substantially tangential direction. ing.

Further, a drive shaft 6 and a guide shaft 7 are provided between the side plates 3 and 4.
is installed parallel to the platen 1, and a carriage 9 to which a print head 8, which will be described later, is fixed is fitted to the drive i1 + decoy 16 and the guide shaft 7.

Further, a spiral groove 10 is carved on the circumferential surface of the drive shaft 6,
A protrusion 11 of a carrier tool 9 is engaged with this spiral groove 10. The drive shaft 6 is rotationally driven by the second motor 12, so that the print head 8 reciprocates beyond the printing width of the printing paper P.

As shown in FIGS. 3 and 4, the print head 8 has a configuration in which m pairs of print hammers 14 and drive devices 15 are provided on a helad base 13 having a substantially U-shaped cross section. That is, the printing hammer 14 includes a plate spring 16 attached to the head base 13, a printing pin 17 attached to the tip of the plate spring 16, and the plate spring J to form a magnetic circuit.
6 and an armature 18 made of magnetic material attached by means of brazing, etc., and a printing pin 17
... are arranged on the same straight line at equal intervals and alternately vertically. The drive device 15 also includes a pair of iron cores J9,1 attached to the head base 13.
9, and the above armature 18 via this iron core 19.19
A permanent magnet 2 that attracts the plate against the spring force of the leaf spring 16.
0 and a coil 21.2 that cancels the magnetic field of this permanent magnet 2o.
1, and are arranged alternately like the printing hammers 14 described above. Furthermore, as shown in FIGS. 3 and 5, the print head 8 configured in this manner is tilted so that the width l in the vertical direction between the print pins 17 and 17 at both ends corresponds to one character. It is attached to 9.

That is, the printing pins 17 are arranged with an inclination such that the distance between adjacent printing pins 14, 14 in the moving direction of the printing paper P is equal to the dot printing interval.

Incidentally, reference numeral 22 in FIG. 1 is a printing mark IJ, which is stretched between the printing paper P and the printing head 8. As shown in FIG.

Then, the carriage 9 is driven to scan the print paper P with the print head 8, and at the same time, each print hammer 14 of the print head r8 is moved in synchronization with the movement of the carriage 9.
to drive. Here, each printing hammer 14 is normally attracted by the magnetic attraction force of the permanent magnet 20 against the spring force of the leaf spring 16, and a minute gap exists between it and the platen 1. , 21vc is applied, the magnetic field of the permanent magnet 20 is canceled, and the spring force of the leaf spring 16 causes one dot constituting a character on the printing paper P to be applied to the platen IVC via the printing press 22 and the printing paper P. Print 23.

After one line of printing is completed, the carry tool 9 is returned to its original position, the printing paper P is fed one line, and the next line is printed.

According to the above configuration, the printing pins 17... are arranged on an inclined straight line, and the driving devices 15 for driving the printing pins 17... are arranged vertically alternately, so that printing can be performed as shown in FIG. The pitch between the pins 17, 17 in the vertical direction becomes smaller, the distance between the dots 23 . . . forming the characters can be narrowed, and the space for the drive device 15 .

Therefore, it is possible to perform high-density printing with a small size, low cost, and high reliability.

In the above embodiment, by changing the reprint angle of the print head 8, it is possible not only to print two or more lines at the same time with one reciprocating movement of the carriage 9, but also to print characters of different sizes. You can also do that.

Further, leaf springs 16 . . . forming each hammer 14 .
As shown in FIG.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a plan view, FIG. 2 is a front view, FIG. 3 is a front view showing the print head portion, and FIG. 4 is a sectional view of the print head. FIG. 5 is a diagram showing the relationship between the printing pin and the dots forming the characters, and FIG. 86 is a plan view showing another embodiment of the leaf spring. P... Printing medium (printing paper), 8... Printing mechanism (printing head), 9... Carriage horn, 17... Printing bin, 15... Drive device.

Claims (2)

[Claims] (1) In a dot printer that prints characters composed of a combination of rnXn vertical and horizontal dots on the printing medium while scanning the printing medium in a direction perpendicular to the direction of movement thereof, printing on the printing medium. a printing mechanism;
and a moving means for reciprocating the printing mechanism by a distance greater than the printing width of the printing medium, the printing mechanism includes an mm printing bin arranged on a straight line having a constant inclination with respect to the scanning direction. and mf15 driving means corresponding to the m printing bins and arranged alternately with the straight line as a boundary, and driving the printing bins. (2) The serial type according to claim 1, wherein the m number of printing bins are arranged at an inclination such that the distance between adjacent printing pins in the direction of movement of the printing medium is equal to the dot printing interval. dot printer.