JPH0534145B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the construction of a print head for a dot printer.

Various input/output devices are used as peripheral devices for computers, one of which is a printing device.

Printing devices can be broadly classified into impact type and non-impact type, and both are directly connected to terminal equipment to record various information.

The requirements for such a printer are that it should be capable of high-quality, high-speed printing, and that it should operate stably with little noise.

Figure 2 explains the printing operation of a dot line printer.
An ink ribbon 3 is placed in front of the ink ribbon 3 with a slight gap between the ink ribbon 3 and the ink ribbon 3. The ink ribbon 3 is moved at a very small speed in a direction perpendicular to the traveling direction of the continuous paper and is wound up.

Further, in front of the printing head 5 is a printing head 5 equipped with a driving device for printing wire 4, and is configured to horizontally reciprocate by a motor.

That is, the printing head 5 is composed of a plurality of printing wire drive devices, and upon receiving a signal, a specific printing wire protrudes and collides with the platen 1, so that the ink of the ink ribbon 3 is printed on the continuous paper 2. .

Multiple pieces (for example 24 pieces) depending on the signal like this
The printing wire selectively protrudes and hits the platen 1, thereby printing characters, figures, etc. However, the problem with such wire dot printers is noise, which is caused by the printing wire hitting the platen 1. The noise is generated when the armature with printing wires is drawn into the yoke, but due to the large number of printing wires 4, the noise generated from one printer exceeds 70 dB, and this noise control has become an issue that requires an urgent solution.

[Conventional technology]

FIG. 1 shows the structure of a printing section of a wire dot printer, and a plurality of such printing sections are arranged to form a printing head.

That is, an excitation coil 8 is provided at one end of a U-shaped yoke 7 formed with a permanent magnet 6 in the center, while a leaf spring 10 having an armature 9 at its tip is fixed to the yoke 7 together with a side magnetic path 11. has been done.

Further, a printing wire 4 is provided at the tip of the armature 9.

Here, the armature 9 has been made of a silicon steel plate, etc., and the side magnetic path 11-
Since a closed magnetic path passing through the armature 9 and the yoke 7 is formed, the armature 9 is connected to the end face 12 of the yoke 7.
is attracted to.

When a signal current is applied to the excitation coil 8 in this state, the resulting magnetic field is designed to cancel out the magnetic flux forming the conventional closed magnetic path, so the armature 9 is brought into an attracted state by the elasticity of the leaf spring 10. The printing wire 4 is released and restored, and due to this restoring force, the printing wire 4 protrudes and hits the platen to perform printing.

Next, when the signal current to the excitation coil 8 stops, a closed magnetic path is again formed by the permanent magnet 6, and the armature 9 is attracted to the end surface 12 of the yoke.

Here, the noise of a wire dot printer is generated not only when the printing wire 4 hits the platen, but also when the armature 9 is attracted to the end surface 12 of the yoke and collides with the end surface. This is a drawback.

[Problem that the invention seeks to solve]

As described above, in wire dot printers, it is a problem to suppress the noise generated when the armature provided with the printing wire collides with the end face of the yoke forming the printing section.

[Means for solving problems]

The problem with upper air is that there is a permanent magnet at one end of the yoke equipped with an electromagnet, and a closed circuit is formed by the armature held by a leaf spring, and when the electromagnet is energized, the magnetic field passing through the armature is canceled out and the armature is activated. In the printing head where suction is released and the wire provided on the armature is made to protrude by the elasticity of the leaf spring to perform printing, the armature is made of (13-17) Cr-(1-4) Al-remaining Fe,
This problem can be solved by a print head for a dot printer, which is characterized by being made of a soft magnetic material that has a soundproofing effect.

[Effect]

(13-17) Cr-(1-4)Al-An anti-vibration alloy made of a soft magnetic material with the remaining Fe absorbs the vibrations generated when the armature collides, thereby reducing the noise level. It is.

The anti-vibration alloy is a metal material that itself has a high damping ability against vibrations, and ferromagnetic, twin-crystal, dislocation-type, etc. are known. (Reference: Compiled by the Japan Institute of Metals, Metals Handbook, page 971) In other words, a typical ferromagnetic type is a ferromagnetic material with a composition of 12Cr-2Al-86Fe called Silentalloy, which is subjected to external stress. The direction of spontaneous magnetization that forms the domain is what absorbs. However, as a result of research, the inventors found that in order to increase the soundproofing effect, the composition ratio (13
~17) It was discovered that the composition of Cr-(1-4)Al-remaining Fe is superior, and the present invention uses such a ferromagnetic type vibration-proof alloy to form an armature to prevent the occurrence of collisions. This is to reduce the noise level.

〔Example〕

In the present invention, the armature is formed using a soft magnetic material consisting of 13 to 17% Cr, 1 to 4% Al, and the remainder Fe. Experiments have shown that if the composition ratio of Cr is more or less than this, sufficient soundproofing effect is not achieved. Not obtained, on the other hand
It has been found that if the composition ratio of Al is less than 1%, a sufficient soundproofing effect cannot be obtained, and if it is more than 4%, the saturation magnetic flux density decreases, making it impractical.

Here, we will discuss the case where the armature 9 is formed using a soft magnetic material of 15Cr-3Al-82Fe. The noise generated when colliding with the end face 12 of the yoke 7 was reduced to 50 dB compared to 75 dB when a conventional silicon steel plate was used, and a remarkable effect could be obtained.

〔Effect of the invention〕

As described above, the present invention has been made to reduce the noise generated during operation of a wire dot printer, and by constructing the armature with a soundproof material made of a soft magnetic material, the noise level can be reduced.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the configuration of a printing section of a wire dot printer, and FIG. 2 is a plan view illustrating the configuration of the wire dot printer. In the figure, 4 is a print wire, 5 is a print head, 6 is a permanent magnet, 7 is a yoke, 8 is an excitation coil, 9 is an armature, 10 is a leaf spring, and 12 is an end face.

Claims (1)

[Claims] 1. A permanent magnet is provided at one end of a yoke equipped with an electromagnet, and a closed circuit is formed by an armature held by a leaf spring, and the electromagnet is energized to offset the magnetic field passing through the armature, thereby increasing the strength of the armature. In the printing head where the suction is released and the wire provided on the armature is made to protrude by the elasticity of the leaf spring to perform printing, the armature is made of 13 to 17% chrome, 1 to 4% chrome.
A printing head for a dot printer, characterized in that it is formed using a soft magnetic material consisting of % aluminum and the remainder iron.