JPH059175Y2 - - Google Patents

Description

[Detailed explanation of the invention] [Summary] This invention relates to the structure of the printing head of a wire dot printer.The aim of this invention is to reduce costs by improving processability. The other end of the leaf spring is screwed to the outer periphery, and the side magnetic path is made of a highly permeable material whose center part protrudes to a position facing both sides of the armature. It consists of a supporting yoke, a core facing the armature, a yoke that connects the yoke and the core, and a coil wrapped around the core. It is a printing head that forms a closed magnetic path that extends to the print head, and the side magnetic path is divided into two parts.The center part facing the armature is made of a highly permeable material, and the outer periphery to which the leaf spring is screwed is made of a magnetic material with excellent machinability. It is constructed by closely joining the two materials.

[Industrial application field]

The present invention relates to the structure of a print head for a wire dot printer.

In recent years, wire dot printers that form characters and the like using dots have been put into practical use as printers for various computer terminals, word processors, and the like.

Among them, serial dot printers record characters by making up dots, so there are many types of characters, etc., and office automation (OA:
Its use as a terminal device in Office Automation is increasing.

These printers are required to be lower in cost.

[Conventional technology]

As shown in the perspective view of FIG. 2, the print head 1 includes a print wire 2, an armature 4 that holds the print wire 2 at one end via a beam 3 (or directly),
A leaf spring 5 with an armature 4 fixed at one end, and a clamper 6 that clamps the other end of the leaf spring 5 from both sides.
and the through hole 7 of the cover 7 stacked on the clamper 6.
The plate spring 5 is screwed to one end thereof with a set screw 8 through a, and a side magnetic path (bypass) 9 with the other end protruding to a position facing both sides of the armature 4 as shown in the figure, and a side magnetic path a yoke 10 supporting 9;
It consists of a core 11 facing the armature 4, a yoke 13 that connects the yoke 10 and the core 11 via a permanent magnet 14, and a coil 12 wound around the core 11. A closed magnetic path is formed through the iron 10 and the core 11 to the armature 4.

The side magnetic path 9 is formed using a highly permeable material such as Permendur, which is an alloy of iron and cobalt, in order to improve magnetic properties for high-speed printing.

Therefore, when the coil 12 is not excited,
The armature 4 is attracted to the core 11 by the magnetic path of the permanent magnet 14 in the counterclockwise direction as indicated by arrow A.

With this configuration, when the coil 12 is excited so that the NS pole of the permanent magnet 14 and the pole of the core 11 are opposite, the core 11 becomes an electromagnet and creates a clockwise magnetic path as shown by arrow B, creating a permanent magnet. It works to cancel the attractive force of the magnet 14.

For this reason, the armature 4 uses the energy stored in the leaf spring 5 to flip up the printing wire 2 upward in the figure, and prints on the printing paper via the ink ribbon.

Although not shown, the suction type print head does not have a permanent magnet in the yoke, and by energizing a coil, it attracts the armature supported by a leaf spring, and prints attached to the armature in the opposite direction to the above. The wire protrudes downward.

Although the above explanation has been made with reference to only one print head, in reality, a predetermined number of such print heads are arranged in a ring shape and used.

Therefore, the individual parts are disk-shaped or ring-shaped as shown in the exploded perspective view of FIG. 3, and are stacked one on top of the other in order to form a print head having the required number of print wires.

[Problem that the invention attempts to solve]

As mentioned above, the side magnetic paths are made using a highly permeable material such as permendile.

This side magnetic path is provided with many screw holes (tap) for screwing the leaf springs, but permendile lacks ductility and is difficult to machine, resulting in poor yields and high costs.

[Means for solving problems]

FIG. 1 is a perspective view of the side magnetic path of the print head of the present invention.

In the present invention, the side magnetic path 15 is divided into two parts, the central part 15b facing the armature 4 is made of a highly permeable material, and the outer peripheral part 1 to which the leaf spring 5 is screwed is used.
5a is a magnetic material with excellent machinability, and the two are closely joined together.

[Effect]

The outer peripheral portion 15a of the side magnetic path 15 is made of a material that is easy to machine (tap), improving yield.
Moreover, the expensive iron-cobalt alloy can be saved accordingly, leading to cost reduction.

〔Example〕

1 and 2 show an embodiment of the present invention.

Identical parts are designated by the same reference numerals throughout the figures.

As shown in the perspective view of FIG. 1, in the printing head of the present invention, the side magnetic path 15 has a donut-like structure in which it is divided into two parts, an outer peripheral part 15a and a central part 15b, and the outer peripheral part to which the leaf spring 5 is screwed. The material 15a is made of a magnetic material such as silicon iron, which has excellent machinability including the tap holder.

And the center part 15b facing the amateur 4
As in the prior art, a highly permeable material such as permendile is used.

They are butted against each other and welded together by electric resistance welding, laser welding, or the like.

Here, it is conceivable that the magnetic properties of the side magnetic path 15 would be deteriorated by making the outer circumferential part 15a of silicon iron, but in reality, the outer circumferential part 15a has a central part that must become thinner toward the tip. The area is much larger than 15b, so the influence can be ignored.

Therefore, by making only the central portion 15b, which forms the magnetic path so as to sandwich the armature 4, from a highly permeable material, it is possible to maintain the same high magnetic properties as in the prior art.

The above explanation was made using a release type print head, but
It is also applicable to suction type print heads.

[Effect of idea]

As explained above, by applying the present invention, processing of the side magnetic path becomes easier, yield is improved, and at the same time, expensive iron-cobalt alloy is saved.
It has great economic and industrial effects, such as cost reduction.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the side magnetic path of the print head of the present invention, Fig. 2 is a perspective view of the print head to which the present invention is applied, and Fig. 3 is an exploded perspective view of the print head to which the present invention is applied. be. In the figure, 1 is the printing head, 2 is the printing wire, 3 is the beam, 4 is the armature, 5 is the leaf spring,
6 is a clamper, 7 is a cover, 8 is a set screw, 9,
15 is a side magnetic path, 10 is a yoke, 11 is a core, 12 is a coil, 13 is a yoke, 14 is a permanent magnet, 15a
is the outer periphery, and 15b is the center.

Claims (1)

[Claims for Utility Model Registration] Amateur 4 holding printing wire 2 at one end
and a leaf spring 5 to which the armature 4 is fixed at one end.
The other end of the leaf spring 5 is screwed to the outer peripheral part 15a, and the center part 15b is screwed to the armature 4.
a side magnetic path 15 formed of a highly permeable material that protrudes to a position opposite to the side surface of the yoke 10 , a yoke 10 that supports the side magnetic path 15 , a core 11 facing the armature 4 , and the yoke 10 and a yoke 13 connecting the core 11 to the core 11, and a coil 12 wound around the core 11, from the armature 4 to a side magnetic path 15, a yoke 10,
It is a printing head that forms a closed magnetic path leading to the armature via the yoke 13 and the core 11, the side magnetic path 15 is divided into two, the central portion 15b facing the armature 4 is made of a highly permeable material, and the plate The printing head is characterized in that the outer peripheral part 15a to which the spring 5 is screwed is made of a magnetic material with excellent machinability, and the two are tightly joined.