JPH044156A - Impact dot head - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an impact dot head for an impact printer.

<Prior Art> FIG. 3 shows a sectional view of a conventional impact dot head. A disk-shaped member 325 made of metal is attached to the end face of the printing wire holding member 313 having a guide hole for holding the printing wire 314 from the armature 306 M2'11, and a disk-shaped member 325 made of metal is attached to the side surface of the disk-shaped member 325 made of metal from the armature 306. The coil spring holder 326 that houses and holds the coil spring 315 that presses the armature 306 into a standby state is arranged in a stacked manner.

<Problems to be Solved by the Invention> However, in such a configuration, after the disk-shaped member 325 made of metal is laminated on the printing wire holding member 313, the coil spring holder 326 is stacked on the disk-shaped member 32 made of metal.
5, there is a problem in that since the disk-shaped member 325 made of metal and the coil spring holder 326 are separate bodies, it takes time to assemble them, impairing the ease of assembly. In addition, the positioning of the printing wire holding member 313 and the coil spring holder 326 becomes inaccurate, and the armature 30
6 became unstable, which caused a decrease in print quality.

The present invention has been made to solve the above problems, and provides an impact dot head that is easy to assemble.

Means for Solving the Problems> The present invention provides a coil spring holding member that holds a coil spring that engages with an armature, and a thin plate member made of metal that contacts the coil spring at the seat of the coil spring. It is characterized in that it is sandwiched between a coil spring holding member and a printing wire holding member, and the coil spring holding member, a thin plate member made of metal, and the printing wire holding member are engaged and fixed together.

<Function> In the impact dot head configured as above,
Since the coil spring holding member, the metal thin plate member, and the printing wire holding member are integrally engaged and fixed, the three parts, the coil spring holding member, the metal thin plate member, and the printing wire holding member, can be handled as an integral part. Easy to assemble,
Positioning accuracy can be improved.

<Example> Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a sectional view of an impact dot head showing an embodiment of the present invention. A plurality of cores 2a are erected on a frame 2 made of a soft magnetic material, and a coil 7 in which a copper wire is wound around a coil bobbin 9 is attached around the core 2a to form an electromagnet. Two through holes are provided for each core 2a on the bottom surface of the frame 2, and the coil terminals 10 of the coil 7 are electrically fixed to a substrate 17 via an insulating plate 20 by soldering. A first yoke plate 3, a second yoke plate 4, and an armature holder 21 are stacked on the outer peripheral surface of the frame 2. Armatures 6 integrally molded by press are arranged at equal intervals on the circumference on the opposing part of the core 2a, and the tip of the armature 6 and the engagement part of the printing wire 14 are brazed at equal intervals on the circumference. It is fixed by. The armature 6 is provided with a through hole 6a, a fulcrum shaft 18 is inserted into the through hole 6a, and the armature 6 is held freely rotatable around the fulcrum shaft 18. The fulcrum shaft 18 is sandwiched between two fulcrum spacers 5 and fixed by pressure contact between the first yoke plate 3 and the armature holder 21. The printing wire 14 is attached to the tip guide 11 attached to the nose 1.
, the intermediate guide 12, and the printing wire hole 13b provided in the nose guide 13, and are guided so as to form a staggered arrangement in two vertical rows at the tip of the printing wire 14. The outer peripheral part 13a of the nose guide 13 is connected to the central opening 2 of the frame 2.
It is positioned by b. In the nose guide 13,
A metal spring seat 25 and a return spring holder 26 for storing and holding a plurality of return springs 15 are stacked and fixed and arranged as an integral part. The return spring 15 presses the armature 6 toward a damper 16 made of a material with excellent damping characteristics.

FIG. 2 shows a nose guide 13 of the present invention, a metal spring seat 25,
An exploded perspective view of the return spring holder 26 is shown. The return spring holder 26 has a plurality of through holes 26a for holding a plurality of return springs 15, and a groove 26d for guiding the armature 6 is provided at the end of the through hole 26a. The positioning shaft 26e of the return spring holder 26 is aligned with the positioning hole 25c of the metal spring seat 25 and the positioning hole 13e of the nose guide 13.
The return spring holder 26, the metal spring seat 25, and the nose position the idler 13 in the rotational direction, and the outer circumference 13c of the nose guide 13 connects with the inner hole 25b of the metal spring seat 25 and the return spring. It engages with the inner peripheral hole 26b of the holder 26 to position the centers of the return spring holder 26, metal spring seat 25, and nose guide 13. The two fixed shafts 26c of the return spring holder 26 are attached to the metal spring seat 25.
The fixing shaft 26c of the return spring holder 26 is caulked on the side of the nose guide 13 opposite to the metal spring seat 25 by passing through the two through holes 25a and the two through holes 13d of the nose guide 13. A return spring holder 26, a metal spring seat 25, and a nose guide 13 are fixed together. In this way, the three parts, the return spring holder 26, the metal spring seat 25, and the nose guide 13, can be handled as one part, and the ease of assembly can be improved.

Next, the operation will be explained with reference to FIG. In the standby state, the spring force of the return spring 15 causes the armature 6 to move to the damper 1.
It is held in a pressed state at 6. Here coil 7
When a pulse current is applied to the armature 6, the magnetic attraction force is applied to the armature 6.
This occurs between the core 2a and the core 2a. The armature 6 is accelerated by this magnetic attraction force and begins to rotate about the fulcrum shaft 18 in the direction of arrow A. Along with this, printing wire 1
4 protrudes and passes through the ink ribbon 22 to the print medium 23.
is collided and pressed onto the platen 24 to form a dot. After the collision, the armature 6 enters a return operation due to the repulsive force at the time of the collision and the spring force of the return spring 15, and is held by the damper 16 after the collision, completing one printing process.

<Effects of the Invention> As described above, according to the present application, a coil spring holding member that holds a coil spring that engages with an armature, and a thin plate member made of metal that comes into contact with the coil spring are provided on the seat of the coil spring, and the thin plate member made of metal is provided. Since the coil spring holding member and the printing wire holding member are sandwiched, and the coil spring holding member, the thin plate member made of metal, and the printing wire holding member are integrally engaged and fixed, the coil spring holding member, the thin plate member made of metal, and the printing wire are held together. Assembling the holding member becomes easier,
Assemblability can be greatly improved.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an impact dot head showing an embodiment of the present invention. FIG. 2 is an exploded perspective view of a nose guide, metal spring seat, and return spring holder showing an embodiment of the present invention. FIG. 3 is a sectional view of a conventional impact dot head. 21... Armature holder 22... Ink ribbon 23... Print medium 24...
・Platen 25...Metal spring seat 26...Return spring holder

Claims (1)

[Claims] A printing wire is engaged and fixed to the tip of an armature, a printing wire holding member for holding the printing wire is disposed near the armature, a coil spring is provided to engage with the armature, and an electromagnet is provided at a suction facing portion of the armature. In the impact dot head, the coil spring engages with the armature, and the impact dot head performs printing by driving the printing wire and applying an impact force to the printing medium by rotating the armature by the attraction force of the electromagnet. A coil spring holding member for holding the coil spring, and a thin plate member made of metal that comes into contact with the coil spring at the seat of the coil spring, and the thin plate member made of metal is held between the coil spring holding member and the printing wire holding member, and the coil spring An impact dot head characterized in that a holding member, a thin plate member made of the metal, and the printing wire holding member are integrally engaged and fixed.