JPH06238920A - Dot impact printer with selectable printing density - Google Patents

Abstract

PURPOSE:To obtain a light and shade figure at sufficient printing quality without changing dot density. CONSTITUTION:A dot impact printer whose printing density is selectable is provided with a reference density pattern generating part 12 which generates a reference density pattern P based on instructions from an operation panel 11 and a printing density setting part 13 which out puts printing head driving pulse T1, T2 widths by changing them by corresponding to printing density to be set up based on instructions through the reference density pattern generating part 12 or a high ranking device 19 or the operation panel 11 and out puts carrier driving pulse corresponding to a predetermined printing speed based on the printing density. Then a printing head 15 hitting printing paper by a plurality of printing wires through an ink ribbon, a printing head driving part 14 driving the printing head 15 based on the printing head driving pulses T1, T2 and a printing part 17 comprised of a carrier driving part 16 driving a carrier on which the printing head 15 is mounted based on a carrier driving pulse K are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dot impact printer capable of selecting print density.

[0002]

2. Description of the Related Art Conventionally, a dot impact printer of this type prints a printing paper via an ink ribbon in which cloth is impregnated with ink by a plurality of printing wires driven by a magnetic attraction force generated by a magnetic coil. Strike and print. Usually, the ink ribbon has a ring shape and can be printed repeatedly by rotating in the same direction.

[0003]

Since this conventional dot impact printer has a mechanism for repeatedly printing using a ring-shaped ink ribbon, the larger the printing amount, the smaller the amount of ink that has penetrated into the ink ribbon. ,
The print density decreases. As described above, since the print density depends on the usage time of the ink ribbon, it is not possible to make the print density selectable, and various improvements have been made with the goal of being legible even if the ink amount is reduced. ing. Therefore, when printing graphs and figures, you can change the dot density to meet the desire to express shades,
Since the printing pattern is changed to deal with it, sufficient printing quality cannot be obtained.

[0004]

A dot impact printer capable of selecting print density according to the present invention includes a standard density pattern generating means for generating a standard density pattern based on an output signal from an internal setting means, and a standard density pattern generating means. Unit or higher-level device or print density setting for outputting an output signal according to a print density set based on an output signal from the internal setting unit and an output signal according to a predetermined printing speed based on the print density And a printing unit capable of printing at a plurality of printing densities and printing speeds based on the output signal from the printing density setting unit.

Further, in the dot impact printer of the present invention capable of selecting print density, the print density setting means changes the print head drive pulse width in accordance with the print density and outputs the pulse, and further based on this print density. A print head that outputs a carrier drive pulse according to a predetermined print speed, the print means strikes a print sheet through an ink ribbon with a plurality of print wires, and the print head based on the print head drive pulse. A print head drive means for driving the print head, and a carrier drive means for driving a carrier on which the print head is mounted based on the carrier drive pulse.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. Referring to FIG. 1 which is a block diagram showing an embodiment of the present invention, in a dot density printer 18 with print density selectable according to this embodiment, a standard density pattern generation unit 12 generates a standard density based on an output signal from an operation panel 11. A pattern P is generated. The print density setting unit 13 changes the widths of the print head driving pulses T1 and T2 according to the print density set based on the output signal from the standard density pattern generating unit 12, the host device 19 or the operation panel 11, and outputs the pulse. Also, a carrier drive pulse K corresponding to a predetermined printing speed based on the print density is output. Printing part 1
Reference numeral 7 designates a print head 15 for striking a print sheet through a plurality of print wires via an ink ribbon, a print head drive unit 14 for driving the print head 15 based on print head drive pulses T1 and T2, and a carrier drive pulse K. And a carrier driving unit 16 for driving a carrier on which the print head 15 is mounted.

FIG. 2 is a sectional view of the print head 15 used in this embodiment, and FIG. 3 is a block diagram of the print head drive unit 14. Referring to FIGS. 2 and 3 together with FIG. 1, the print head 15 includes an armature 2 having a print wire 1 attached to its tip, a yoke 3, and a ring yoke 4.
And the coil 5 form a magnetic circuit. The print head drive unit 14 supplies a current to the coil 5. By supplying the print head drive pulses T1 and T2 to the switching elements 21 and 22, the current shown in FIG. As a result, the armature 2 is magnetically attracted toward the yoke 3, and the printing wire 1 attached to the tip of the armature 2 strikes the printing paper 7 via the ink ribbon 6 to print. When the current flowing through the coil 5 is cut off by the print head drive pulse T2, the armature 2 is returned to its original position by the return spring 9. FIG. 5 shows an example of the relationship between the print head drive current pulse width t2 and the print density when a new ink ribbon 6 and print head 15 are used. The relationship between the print head drive current pulse width t2 and the print density shown in FIG. 5 is specific to the ink ribbon 6 and the print head 15 to be used, but in most cases, the curve shown in FIG.

Table 1 shows the print head drive current pulse width t2 at the time of printing by the printing unit 17 according to the density setting ranks of the standard density pattern P output from the standard density pattern generating unit 12.
An example of the printing speed is shown. The standard density pattern P is rectangular and printed with the same dot density.
The higher the number, the darker the concentration. The print density setting unit 13 supplies the print head drive pulses T1 and T2 corresponding to the print head drive current pulse width t2 to the print head drive unit 14 according to the density setting rank of the standard density pattern P, and the carrier drive corresponding to the print speed. The pulse K is output to the carrier driving unit 16, respectively.

[0009]

[Table 1]

Next, the operation of this embodiment will be described with reference to FIG. 1 and Table 1. First, in order to set the standard density, the standard density pattern generator 12 outputs the standard density pattern P in accordance with an instruction from the operation panel 11. The standard density pattern P is printed by the printing unit 17 via the print density setting unit 13 based on the density setting ranks. From the print result of the standard density pattern P, for example, the density setting rank is set in the print density setting section 13 as the standard density by the operation panel 11. When the print density setting unit 13 receives a print command based on the standard density from the host device 19 or the operation panel 11, the print unit driving pulse T corresponding to the print head drive current pulse width t2 of the density setting rank t2 = 290 μs is received by the print unit 17.
1 and T2, and a carrier drive pulse K corresponding to a printing speed of 1080 Hz are output. When the print density setting unit 13 receives a density down command from the higher-level device 19 or the operation panel 11, the print density setting unit 13 causes the print unit 17 to output the print head drive current pulse width t2 of the density setting rank t2 = 270 μs.
The print head drive pulses T1 and T2 corresponding to the print speed and the carrier drive pulse K corresponding to the print speed of 1080 Hz are output. On the contrary, when the print density setting unit 13 receives a density up command from the host device 19 or the operation panel 11 when the standard density is set, the print density setting unit 13 causes the printing unit 17 to output the print head drive current pulse width t2 of the density setting rank. = 31
Print head drive pulses T1 and T2 corresponding to 0 μs
And a carrier drive pulse K corresponding to a printing speed of 1080 Hz.

As a matter of course, the set values of the print head drive current pulse width t2 and the print speed differ depending on the print head and the ink ribbon used.

[0012]

As described above, according to the present invention,
A standard density pattern is generated based on the output signal from the internal setting means, and printing is performed at a printing density and a printing speed set based on the standard density pattern to meet the desire to express light and shade. Change
Sufficient print quality can be obtained without having to change the print pattern.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

FIG. 2 is a sectional view of a print head used in this embodiment.

FIG. 3 is a configuration diagram of a print head drive unit used in this embodiment.

FIG. 4 is a waveform of a current flowing through a coil of the print head used in this example.

FIG. 5 is a diagram showing an example of a relationship between a print head drive current pulse width and print density when a new ink ribbon and a print head are used.

[Explanation of symbols]

 1 Printing Wire 2 Armature 3 Yoke 4 Ring Yoke 5 Coil 6 Ink Ribbon 7 Printing Paper 8 Platen 9 Return Spring 11 Control Panel 12 Standard Density Pattern Generating Section 13 Printing Density Setting Section 14 Printing Head Driving Section 15 Printing Head 16 Carrier Driving Section 17 Print unit 18 Dot impact printer 19 Upper device 21,22 Switching element K Carrier drive pulse P Standard density pattern T1, T2 Print head drive pulse t1, t2 Print head drive current pulse width

Claims (4)

[Claims] 1. A standard density pattern generating means for generating a standard density pattern based on an output signal from the internal setting means, and setting based on an output signal from the standard density pattern generating means or a host device or the internal setting means. Print density setting means for outputting an output signal according to the selected print density, and print means capable of printing with a plurality of print densities based on the output signal from the print density setting means. Selectable dot impact printer. 2. The printing density setting means changes and outputs a print head drive pulse width according to the printing density, and the printing means prints by striking a printing paper via an ink ribbon with a plurality of printing wires. The print according to claim 1, further comprising: a head, a print head drive unit that drives the print head based on the print head drive pulse, and a carrier drive unit that drives a carrier on which the print head is mounted. Dot impact printer with selectable density. 3. A standard density pattern generating means for generating a standard density pattern based on an output signal from the internal setting means, and setting based on the output signal from the standard density pattern generating means or a host device or the internal setting means. A print density setting means for outputting an output signal corresponding to a print density and an output signal corresponding to a printing speed predetermined based on the print density; and a plurality of print density setting means based on the output signals from the print density setting means. A dot impact printer with selectable print density, comprising: a printing unit capable of printing at a print density and a print speed. 4. The print density setting means changes and outputs a print head drive pulse width according to the print density, and further outputs a carrier drive pulse according to a print speed predetermined based on the print density. The print means includes a print head for striking a print sheet through an ink ribbon with a plurality of print wires, a print head drive means for driving the print head based on the print head drive pulse, and the carrier drive pulse. 4. The dot impact printer with selectable print density according to claim 3, further comprising carrier driving means for driving a carrier on which the print head is mounted.