JPS6110465A - Printing head of dot printer - Google Patents

Abstract

PURPOSE:To raise the printing speed and the working accuracy, by a method wherein after connecting the surface of an armature on the attraction side to an iron core to a plate spring, the inclined surface of a fixed angle by which the armature is face to face contacted to the end surface of iron core is formed when a hammer is kept. CONSTITUTION:In the case of carrying out printing operation, when current is flowed to the coil 8 made to be a pair together with a desired print wire with a drive circuit, the megnetic field having the reverse direction to the direction of the magnetic field generated with a permanent magnet 7 is generated in the magnetic circuit consisting of an iron core 3 and the magnetic field of the permanent magnet 7 is negated. Therefore, an armature 4 falls apart from the iron core 3 by the spring force of a plate spring 2. A print wire 5 is guided by guides 6, 6' and projected to the right from the top of a nose 12. The top of the print wire 5 collides with an ink ribbon and a paper and the dot is formed.

Description

[Detailed description of the invention] [Technical field to which the invention pertains] This invention biases a leaf spring with a permanent magnet, and excites a magnet coil provided in a magnetic path of the permanent magnet, thereby increasing the magnetic field of the permanent magnet. The biased leaf spring is released by canceling out the biased leaf spring, and the print head for the dot printer drives the print wire.

[Prior art and its problems]

In this type of conventional print head, in order to stabilize the operation and make effective use of magnetic force, one side of the iron core is formed into an inclined surface at a predetermined angle so that the armature and the iron core come into surface contact when the hammer is held. . However, due to the accuracy of the inclination angle of each iron core, it is difficult to make surface contact VC at all contact points between the many armatures and the iron core, and there are variations in the air gap between the armature and the iron core, which makes high-speed printing difficult. In some cases, variations in the operation of the hammers occurred due to differences in magnetic force due to differences in the air gap between each hammer, or due to uneven contact between the core and the armature (driving, etc.).Therefore, high-precision machining was applied to the end face of the core. However, this method had the drawback of being expensive, as the variation was minimized.

[Purpose of the invention]

The present invention improves the drawbacks of the conventional device described above, and provides a print head for a low-cost dot printer that is capable of high-speed printing, does not require high processing precision, and can perform stable operation. The purpose is to

[Summary of the invention]

The present invention biases a leaf spring with a permanent magnet, cancels the magnetic field of the permanent magnet by excitation of a magnet coil, releases the biased leaf spring, and drives the print wire in the print head of a dot printer. After attaching the side of the armature that is attracted to the iron core to the leaf spring by brazing, etc....7
This is a print head for a dot printer that can print at high speed and at a low price without requiring high-precision machining because it is formed on an inclined surface at a predetermined angle so that the armature and the end face of the iron core are in surface contact when held.

〔Effect of the invention〕

According to the present invention, by processing the back surface of the armature after joining the leaf spring and the armature, it is possible to easily reduce variations in the inclination angle and air gap to a very small level without requiring high-precision processing. Operation is stable,
It is possible to provide a low-cost printer that is capable of high-speed printing.

[Embodiments of the invention]

The present invention will be explained in full detail below with reference to the drawings.

FIG. 1 is a schematic cross-sectional view showing one embodiment of a print head for a dot printer according to the present invention, and FIGS. 2 and 3 are schematic cross-sectional views showing a hammer unit and a magnet unit of the print head for a dot printer according to the present invention. .

Code 1 has N grooves (N=1.2...)'
2 is a plate spring with N tongues, 3 is N iron cores located at positions corresponding to the grooves of the yoke plate,
4 is an N (
A solid armature, 5 is N printed wires each attached to an anti-air, 6 and 6' are guides that regulate the direction of movement of the printed wire 5, 7 is a ring-shaped permanent magnet, and 8 is wound around the iron core 3. There are N coils, 9 is a ring-shaped yoke, 10 and 11 are spacers, and 12 is a nose.

Next, the assembly and processing method will be explained. First, as shown on the right side of FIG. 2, attach the armature 4 of the leaf spring 2 by brazing, etc.
Leaf spring 21 spacer 10. Assemble the nose 12 using screws etc., attach the guide 6.6' to the nose 12, pass the printed wire 5 through the guide hole of the guide 6.6', and then
Attach four strands such as brazing to the tip of the armature,
- Configure Nununinote 13. After configuring as above, as shown on the left side of Fig. 2, attach a rebar to the nose 12 that allows the tip of the anti-air to be bent by a predetermined amount toward the iron core, and use a milling machine or the like to connect all the hangers 7. The back side of the attached second armature shown by the dotted line 1111 on the left is processed so that it becomes flush with the surface of the iron core side of the yoke grating 1. After this, the jig is cleared 7.

Next, as shown in Fig. 3, the permanent magnet 7 and yoke 9 are attached to the iron core 3 by adhesive or the like, and the coil 8 is attached to each iron core to form a metal flange 14 on the end face of the yoke. Process it.

1 & after 2, no 1 mauni noto 13. ! : A print head is created by fixing the Macnet unit 14 with screws or the like and magnetizing it. By assembling and processing as described above, the amount of air gap between each 7, N, 7 and the iron core is uniform without the need for high-precision processing, and since the contact between the iron core and the armature is surface contact, Variations in the operation of each hammer are reduced, and a print head capable of high-speed printing can be manufactured at a low cost.

Next, the operation of this print head will be explained. First, when the coil 8 is not excited, that is, when no printing operation is performed, the permanent magnet 7. York 9. Yoke plate 1. Amateur 4. In the magnetic circuit constituted by the iron core 3, the armature 4 is attracted to the end face of the iron core 3 by the magnetic force of the permanent magnet 7, so that the tongue piece of the leaf spring 2 is biased toward the iron core 3. Next, when performing a printing operation, when a current is shunted by a drive circuit (not shown) to the coil 8 paired with the desired print wire, the magnetic circuit has a direction opposite to the direction of the magnetic field generated by the permanent magnet 7. A magnetic field is generated and the magnetic field of the permanent magnet 7 is canceled, so the anteure 4 is separated from the iron core 3 by the biasing force of the leaf spring 2, and the printed wire 5 is guided by the guide 6.6' and the tip of the nose 12. The ink ribbon and paper (not shown) fly out from the print wire 5 as shown on the right side of FIG.
By again cutting off the direct current driving the coil, the armature 4 is again biased towards the iron core.

As described in detail below, according to the present invention, high precision
There is no need to perform roe. It is possible to provide a print head for a dot printer with small variations in operation.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view showing an embodiment of a print head according to the present invention, and FIGS. 2 and 3 are schematic cross-sectional views showing a method of assembling and processing the print head according to the present invention. 2: Leaf spring, 3: Iron core, 4: Amateur. 5-niblint wire, 7-permanent magnet. 8: Coil. Agent Patent attorney Noriyuki Chika (and 1 other person) Figure 1

Claims (1)

[Claims] In a print head of a dot printer that biases a leaf spring with a permanent magnet, cancels the magnetic field of the permanent magnet by excitation of a magnetic coil, and releases the biased leaf spring to drive a print wire, the print head is attached to the leaf spring. The surface of the armature on the side that is attracted to the iron core is formed into an inclined surface of a predetermined angle such that the end surface of the armature and the iron core come into surface contact when the armature is held by the hammer after the armature is joined to the leaf spring by brazing or the like. Characteristic dot printer print head.