JPH02184456A - Printing head - Google Patents

Abstract

PURPOSE:To prevent a printing wire from being broken by being caught by a ribbon and reduce wear of the tip of the wire by a construction wherein a printing wire of a printing head is caused to strike a rubber film, and a hygroscopic metallic printing pin containing an ink therein prints on a printing paper. CONSTITUTION:A porous, hygroscopic metallic printing 19 is provided with protruding parts 19a, 19b. Rubbers 20a, 20b are provided on the printing direction side of the parts 19a, 19b, and a rubber film 21 is provided on the opposite side. A plurality of the printing pins 19, each of which is provided with the rubbers 20a, 20b and the rubber film 21, are fitted into a plurality of guide holes provided in a frame 22 mounted on a printing head, correspondingly to and on the forward side of the printing wires 2 with respect to the printing direction of the wires. The frame 22 is provided also with an ink-supplying pipe 23 and an ink tank 24 for supplying the printing pins 19 with an ink at any desired time. In this construction, when the printing wire 2 supported by a guide member 15 is caused to strike the rubber film 21, the porous printing pin 19 containing the ink is caused to strike a printing paper 17 and a platen 18, thereby printing.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a print head for use in an impact type dot matrix printer.

[Conventional technology]

Conventionally, a print head used in this type of printing device performs printing by pressing a printing wire against a printing paper or a platen through an ink ribbon.

[Problem to be solved by the invention]

The conventional print head described above prints by pushing the print wire against the print paper and platen through the ink ribbon, which can cause the ribbon to get caught, causing accidents such as breakage of the print wire, or There was a drawback that the leading edge in the printing direction was significantly worn, leading to a deterioration in printing quality.

Furthermore, many of the ink ribbons used in conventional printing devices are of the endless type, which has the disadvantage that the print density decreases with each stop during use.

On the other hand, an ink dot type print head has been considered as a means to solve the above-mentioned problems, but it has the drawback of being complicated in structure and very expensive.

An object of the present invention is to provide a print head that solves the above problems.

[Means to solve the problem]

In order to achieve the above object, the present invention has a plurality of electromagnetic actuators formed by a yoke, an armature, and a coil, and a printing method that aligns a plurality of printing wires with a plurality of guide members to perform printing in a predetermined manner. In the head, a plurality of hygroscopic metal printing pins having a rubber film on the side opposite to the printing direction are placed in the plurality of guide holes of play 1 to face the printing wire ahead of the tip of the printing wire in the printing direction. Further, an ink section for supplying ink to the printing pin is attached.

〔Example〕

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

FIG. 2 is a half sectional view showing the structure of the print head. In the figure, inside the nose 1a of the head frame 1 are a plurality of printing wires 2 that reciprocate and their guide members 1.2.
13, 14, and 15 are stored. The armature 7 is pressed against the ring yoke 4 by a support rubber 8, and the pressed end 7a is connected to an armature guide 9.
It is positioned by being pressed against it. The armature 7 is rotatable between the stopper plate 10 and the suction surface 3a. Further, a spring 6 is provided adjacent to the magnetic coil 5 and has one end in contact with the armature 7, and the armature 7 is pressed against the stopper plate 10. Here, the spring 6
is a coil spring, which is housed in the spring holder 11.

On the other hand, the printing wire 2 has its rear end fixed to the rotating end of the armature 7. The tip of the wire 2 is inserted into the guide holes 12a, 13a of the guide members 12, 13, 1.4 housed in the nose 1a of the head frame 1.

Guide hole 15 provided in guide member 15 via 1.4a
It is held in place by a.

In such a structure, when the magnetic coil 5 is selectively energized, the magnetic coil 5 emits magnetism, and at this time, the armature 7 rotates around the end 7a pressed by the support rubber 8, and at the same time the armature 7 The tip of the printing wire 2 attached to the tip of the ink ribbon 16. Printing is performed by pressing the printing paper 17 and platen 18. After printing, when the magnetic coil 5 is de-energized, the armature 7 is returned to the initial position together with the printing wire 2 by the spring 6. Here, the initial position refers to a position where the rotating end of the armature 7 is pressed against the stopper plate 10.

A partially enlarged sectional view of an embodiment according to the present invention is shown in FIG.

A protrusion 19a is provided on a porous hygroscopic metal printing pin 19.

19b, and rubber 20a, 20b is provided on the printing direction side of the projections 19a, 19b.
, 19b, a rubber film 21 is provided on the side opposite to the printing direction. The aforementioned rubber 20a is placed in a plurality of guide holes of a frame 22 attached to the print head so as to face the print wire 2 ahead of the printing direction of the print wire 2 of the print head.

20b, a plurality of printing pins 19 provided with a rubber film thickness z1 are attached.

The frame 22 also includes a printing pin 19 made of porous metal.
The ink supply pipe 23.
An ink tank 24 is provided.

In such a structure, by pressing the rubber film 21 with the printing wire 2 held by the guide member 15, the porous metal printing pin 19 containing ink is attached to the printing paper 1.
7. Printing is performed by pressing the platen 18. After printing, the printing pin is moved by the elasticity of the rubbers 20a and 20b. Return to the position before the printing operation was performed.

Ink is supplied from the ink tank 24 through the supply pipe 23 to the printing pin 19 as needed.

〔Effect of the invention〕

As explained above, in the present invention, the printing wire of the print head presses against the rubber film, and the printing pin made of an ink-containing hygroscopic metal prints on the printing paper. Breakage accidents are eliminated, wear of the tip of the printing wire in the printing direction is reduced, and a printing head with extremely high reliability can be provided. Furthermore, ink is constantly supplied from the ink tank to the hygroscopic metal printing pins, so that printing with a constant density is always achieved and high quality printing is maintained.

On the other hand, according to the present invention, it is possible to provide a print head that has a simpler structure and is less expensive than the conventional ink dot type print head.

[Brief explanation of the drawing]

FIG. 1 is a partially enlarged sectional view showing an embodiment of the present invention, and FIG. 2 is a half sectional view showing a conventional print head. Head frame 2...Printing wire 3...Yoke 3a...Yoke suction surface 4...Ring yoke 5...Coil 6...Spring
7... Armature 7a Armature end
8. Support rubber 9... Armature guide

Claims (1)

[Claims] (1) In a print head that has a plurality of electromagnetic actuators formed by a yoke, an armature, and a coil, and performs printing in a predetermined manner by aligning a plurality of printing wires with a plurality of guide members, a plurality of plates are used. A plurality of hygroscopic metal printing pins having a rubber film on the side opposite to the printing direction are provided in the guide hole facing the printing wire beyond the tip of the printing wire in the printing direction, and A print head characterized by being equipped with an ink section that supplies ink.