JPH05131651A - Wire dot printing head - Google Patents

Abstract

PURPOSE:To provide a wire dot printing head used in a printer capable of performing efficient printing by minimizing the loss of the printing energy from an intermediate guide at an impact time. CONSTITUTION:An intermediate guide 23 guiding the advance and recession of a wire 22 is provided in the guide frame 21 of a wire dot printing head and the springs 24 energizing the intermediate guide 23 in a printing direction to position the same are provided in the guide frame 21. Recessed parts are provided in the vicinity of both ends of the rear of the intermediate guide 23 and one ends of the springs 24 are engaged with the recessed parts.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire dot print head used in a printer device.

[0002]

2. Description of the Related Art FIG. 3 is a side view showing a structure of a conventional multi-layer structure (two-layer structure) print head. In the drawing, 1 is a print element group of A layer and 2 is a print element group of B layer. .. Each of the printing element groups 1 and 2 comprises a plurality of printing elements 3 arranged at equal intervals in the circumferential direction. The structure and operation of each print element group will be described below, taking the upper left one (layer B) in FIG. 3 as an example.

The printing element 3 comprises a core 4, an armature 5, a permanent magnet 6 and a coil 7. The armature 5 is supported by a leaf spring 8 in a cantilever manner, and a wire 9 for printing is attached to the armature 5 via a beam 10. Although not shown, a side magnetic path is provided on the side of the armature 5 to compensate for the insufficient cross-sectional area of the leaf spring 8 as a magnetic path.

During non-printing, the coil 7 is not energized,
The armature 5 is attracted to the core 4 against the biasing force of the leaf spring 8 by the magnetic flux formed by the permanent magnet 6 passing through the core 4 and the like.

At the time of printing, the coil 7 is energized for a predetermined time. As a result, a part of the magnetic flux is canceled out, and the armature 5 which is biased by the leaf spring 8 is released from the attraction by the core 4 and is rotated by a predetermined amount. Printing is performed by (9) an operation of striking the platen via a ribbon paper.

The energization of the coil 7 is stopped immediately before the completion of printing, and the wire 9 that has completed printing returns to the original position together with the armature 5 attracted to the core 4. The configuration and operation of the other printing elements are the same.

In the print head having the above-described structure and operation, the intermediate guide 11 for guiding each wire 9 is provided.
Are held in the grooves 13 of the guide frame 12, as shown in detail in FIG. Each wire 9 is guided by the intermediate guide 11 and the guide portion 14 of the guide 12 of the guide frame 12 to move forward and backward.

[0008]

However, in the above-mentioned conventional structure, the intermediate guide 11 has the recess 1 with some backlash.
Since the wire 9 is held within the wire 3, the wire 9 can be moved in the vertical direction in FIG. 4 at the time of impact, and the printing energy is lost accordingly.

An object of the present invention is to provide a wire dot print head capable of performing efficient printing by minimizing the loss of printing energy from the intermediate guide at the time of impact.

[0010]

To achieve the above object, in the present invention, in a wire dot print head in which an intermediate guide for guiding a wire is held in a guide frame, the intermediate guide is provided in the guide frame. Is provided with a spring for urging and positioning the sheet in the printing direction (first configuration).

In addition, in the wire dot print head of the above-mentioned first configuration, recesses are provided near both ends of the back surface of the intermediate guide, and one end of the spring is engaged in the recess (second configuration). Configuration).

[0012]

During the impact operation of the wire, the intermediate guide is biased and positioned by the spring to be in a fixed state, so that the loss of printing energy which has been a problem in the past is eliminated. In addition, when the wire returns after impact, the intermediate guide has a degree of freedom, and lateral deflection of the wire after impact is reduced by the wire positively hitting the intermediate guide.

Particularly, in the case of the second structure, the holding of the intermediate guide by the spring is stable and effective.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is an explanatory view of the structure of the main part of the wire dot print head of this embodiment (FIG. 1A shows a wire reset state, and FIG. 1B shows a state immediately after impact). Reference numeral 21 is a print head guide frame, 22 is a wire, 23 is an intermediate guide, and 24 is a spring.

The guide frame 21 has a groove 25 and a guide portion 26, and the intermediate guide 23 is held in the groove 25. The wire 22 is guided by the intermediate guide 23 and the guide portion 26 to move back and forth. The spring 24 is arranged in the groove 25 and biases the intermediate guide 23 in the printing direction (upward direction in FIG. 1).
Are positioned as shown in FIG. 1 (A) at the time of wire reset (abutting on the upper wall of the groove 25).

During the impact operation of the wire 22, the wire 22 advances while the intermediate guide 23 is positioned as described above, so that the loss of printing energy, which has been a problem in the past, is eliminated. Also, after impact, the wire 22
When is returned, the intermediate guide 23 has a degree of freedom,
Lateral movement of the wire 22 after impact is reduced by the wire 22 positively hitting the intermediate guide 23.

As shown in FIG. 2, the intermediate guide 23
Recesses 27 are provided in the vicinity of both ends of the back surface (lower surface in FIGS. 1 and 2) of the spring, and one end of the spring 24 (upper end in FIG. 1) is provided in the recess 27.
By engaging with, the holding of the intermediate guide 23 becomes stable, and the wire returning operation becomes smoother. 28 is a hole for guiding the wire 22.

[0019]

As described above, according to the present invention, it is possible to minimize the loss of printing energy from the intermediate guide at the time of impact of the wire, and it is possible to perform efficient printing. If the recesses are provided near both ends of the back surface of the intermediate guide and one end of the spring is engaged with the recesses, the returning operation of the wire becomes smoother.

[Brief description of drawings]

1A and 1B are structural explanatory views of a main part of a wire dot print head according to an embodiment of the present invention, in which FIG. 1A shows a wire reset state and FIG. 1B shows a state immediately after impact.

FIG. 2 is a sectional view of an intermediate guide according to an embodiment of the present invention.

FIG. 3 is a side view showing the structure of a conventional wire dot print head.

FIG. 4 is a detailed view of an essential part of FIG.

[Explanation of symbols]

 21 Guide Frame 22 Wire 23 Intermediate Guide 24 Spring 25 Groove 27 Recess

Claims (2)

[Claims] 1. A wire dot print head having an intermediate guide (23) for guiding a wire (22) held in a guide frame (21), wherein the intermediate guide (2) is provided in the guide frame (21).
3) The spring (2) that urges and positions the print direction.
4) A wire dot print head characterized by being provided. 2. A recess (27) is provided near both ends of the back surface of the intermediate guide (23), and a spring (2) is provided in the recess (27).
4. The wire dot print head according to claim 1, wherein one end of 4) is engaged.