JPH0548746B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a wire type dot printer head, and more particularly to an armature position regulating structure.

[Prior art] As a conventional wire-type dot printer head,
For example, the one shown in Japanese Patent Publication No. 57-54312 is known. This structure prevents the plunger fixed to the armature from colliding with the core when the armature (actuating plate) is attracted by the coil, so that the armature collides with the sub-yoke (driven member mounting body). It is composed of

[Problems to be Solved by the Invention] However, in the conventional structure, since the entire surface of the armature on the sub-yoke side contacts the sub-yoke, the kinetic energy of the forward stroke is absorbed during this contact, and the return speed of the armature decreases. depends largely on the spring force of the spring that biases the armature toward the return stroke. Therefore, if the spring force is increased in order to improve the return speed of the armature, the forward stroke speed decreases, resulting in the problem that the attraction force of the plunger by the core must be increased. Furthermore, since the sub-yoke forms part of the magnetic circuit and is made of a magnetic material, there is a problem in that when the armature comes into contact with the sub-yoke, the speed of the return stroke decreases due to the influence of residual magnetism.

SUMMARY OF THE INVENTION An object of the present invention is to provide a wire-type dot printer head that can achieve a high printing speed by increasing the return speed of the armature without increasing input energy.

[Means for Solving the Problems] In order to solve the above problems, the present invention fixes a centering ring made of a non-magnetic metal member to the main yoke inside a plurality of coil bobbins.
The operating stroke of the armature is regulated by the collision between the armature and the centering in the attracted state, and gaps are formed between the core and the plunger, and between the sub-yoke and the armature. The kinetic energy of the armature is stored as the energy of the deflection of the armature, and this energy is used in a double stroke to return the armature at high speed.

[Example] Hereinafter, the present invention will be explained with reference to illustrated examples.
FIG. 1 shows an embodiment of a wire type dot printer head according to the present invention. This embodiment is composed of a wire unit 10 shown in FIG. 2, an electromagnet unit 20 shown in FIG. 3, and an armature unit 30 shown in FIG.
0, 20, and 30 are fixed together by means not shown.

Wire unit 10 (see FIGS. 1 and 2) The wire unit 10 has a nose 12 on which a plurality of wires 11 are arranged. The plurality of wires 11 are slidably guided by the nose 12, and have straight ends and circumferential rear ends. Further, the plurality of wires 11 are urged rearward by a wire return spring 14 disposed between a wire pin 13 fixed to the rear end and the nose 12.

Electromagnet unit 20 (see Figures 1, 3, and 4) The electromagnet unit 20 includes a cup-shaped main yoke 2.
A cylindrical center ring 22 made of non-magnetic metal is fixed to the center of the bottom surface of the wire 1 by spot welding or the like, and a cylindrical core 23 is provided outside the center ring 22 to correspond to the plurality of wires 11. and fixed in a circumferential manner. A cylindrical coil bobbin 25 having flanges at both ends, around which a coil 24 is wound, is attached to each of the cores 23, and the coil bobbin 25 has two positioning legs 25.
a, 25a, and this leg 25a has a conductive pin 2.
6 is buried. The winding start and winding ends of the coil 24 are connected to the conductive pins 26, respectively.
Fixed.

A flexible printed board 28 is connected to the opposite side of the main yoke 21 from the core 23 via an insulating plate 27.
The main yoke 21 and the insulating plate 27 are provided with positioning holes 21a and 27a into which the legs 25a of the coil bobbin 25 are inserted, and the flexible printed board 28 is provided with the conductive pins 26. A pin hole 28a is provided for insertion. The legs 25a of the coil bobbin 25 and the conductive pins 26 are inserted into the positioning holes 21a of the main yoke 21, the positioning holes 27a of the insulating plate 27, and the pin holes 28a of the flexible printed board 28, and the conductive pins 26 are inserted into the flexible printed board 28. It is soldered and fixed to 28. Thereby, the coil bobbin 25, main yoke 21, insulating plate 27, and flexible printed board 28 are assembled into one body. Further, a notch portion 25b is formed in the flange portion of the coil bobbin 25 on the side of the flange portion of the adjacent coil bobbin 25. In the figure, the cutout portion 25b is formed only on one adjacent side, but the cutout portion 25b may be formed on both sides.

Armature unit 30 (see FIGS. 1 and 5) The armature unit 30 has a cover 31 that is fitted around the outer periphery of the main yoke 21. A cylindrical portion 31a is formed inside the corresponding portion. A guide groove 31b is formed in the cylindrical portion 31a to guide one end of an armature 32 provided corresponding to each of the plurality of cores 22. Further, the cover 31 is formed with a sub-yoke mounting portion 31c on which the sub-yoke 33 is placed between the portions where the armature 32 is disposed. A plunger 34 is fixed to the armature 32 at a portion corresponding to the core 23.
A protrusion 32a is formed by half-blanking on the outer side of the protrusion 32a. The sub-yoke 33 is formed with a protrusion hole 33a into which the protrusion 32a is inserted. Further, a chamfered portion 34a is formed at the tip of the plunger 34 on the side of the core 22 at an angle at or near the rotation angle of the armature 32. Further, an armature spring 35 is disposed between the cover 31 and the armature 32, and the armature spring 35 causes the protrusion 3 of the armature 32 to
2a is inserted into the projection hole 33a of the sub-yoke 33, and the other end of the armature 32 is biased so as to come into contact with an O-ring 37, which will be described later. A thin plate 36, an O-ring 37 made of rubber, and a thin plate 38 are disposed inside the cylindrical portion 31a of the cover 31 to receive one end of the armature 32.

Therefore, the armature unit 30 is assembled as follows. A thin plate 36, an O-ring 37, and a thin plate 38 are sequentially installed inside the cylindrical portion 31a of the cover 31.
Place. Further, an armature spring 35 is disposed outside the cylindrical portion 31a. Next, insert the inner part of the armature 32 into the guide groove 21b of the cover 31.
and place the outer part of the armature 32 on the armature spring 35. After that, the sub-yoke 33 is placed on the sub-yoke mounting portion 32 of the cover 31.
Then, the protrusion of the armature 32 is engaged with the protrusion hole 33a of the sub-yoke 33. This completes the assembly of the armature unit 30.

Overall assembly The entire assembly is performed as follows. First, each unit 10, 20, 30 is assembled separately in advance as described above. Then, the plunger 34 of the armature unit 30 is connected to the coil bobbin 2.
The end of the main yoke 21 of the electromagnet unit 20 is placed on the sub-yoke 33 so as to be located inside the sub-yoke 33. Next, the center of the nose 12 of the wire unit 10 is inserted into the center of the electromagnet unit 20, and the nose 12 is brought into contact with the flexible printed board 28 of the electromagnet unit 20. Then, the outer periphery of the nose 12 and the outer periphery of the cover 31 are sandwiched using fixing metal fittings (not shown). As a result, each unit 1
0, 20, and 30 are fixed together.

In the thus assembled state, the centering 22 protrudes from the sub-yoke 33 toward the armature 32 by about 60 μm. Therefore, when the armature 32 comes into contact with the centering 22, a gap s is created between the armature 32 and the sub-yoke 33 on the centering 22 side. Further, the lengths of the plunger 34 and the core 23 are formed so that a gap t is created between the plunger 34 and the core 23 when the armature 32 comes into contact with the centering 22.

Operation Next, the operation will be explained. When the coil 24 is not energized, the armature 32 is in contact with the thin plate 38 due to the biasing force of the wire return spring 14. When the coil 24 is energized, the core 2
3, the plunger 34 is pulled, and the armature 32 rotates around the projection hole 33a of the sub-yoke 33 and comes into contact with the centering 22. As a result, the rear end of the wire pin 13 is broken and the wire 11 protrudes from the front surface of the nose 12, and the paper is pressed against the platen via an ink ribbon (not shown) to perform dot printing. When the excitation of the coil 24 is cut off, the armature 32 returns to rotation around the protrusion hole 33a of the sub-yoke 33, and the thin plate 38
comes into contact with. Also, the wire 11 is connected to the armature 32
The wire is returned by the biasing force of the wire return spring 14 so as to flow.

Effects of the Embodiment As described above, the centering 22 made of a non-magnetic material is fixed to the main yoke 21 inside the plurality of coil bobbins 25. The collision between the sub-yoke 33 and the armature 3 is restricted by the collision with the centering 22.
2, so when the armature 32 collides with the centering 22, the kinetic energy of the forward stroke is stored as the energy of the deflection of the armature 32, and is released in the return stroke of the armature 32. can do. As a result, the return speed of the armature 32 is increased without increasing the input energy for driving the armature, and a high printing speed can be obtained. Furthermore, since the centering ring 22 is made of a non-magnetic material, even if the armature 32 comes into contact with the centering ring 22, there is no attraction phenomenon due to the influence of residual magnetism, and the return characteristic is good.

[Effects of the Invention] As is clear from the above description, according to the present invention, a centering made of a non-magnetic metal member is fixed to the main yoke inside the plurality of coil bobbins, and the operating stroke of the armature is controlled. In the attracted state, the armature is regulated by collision between the armature and the centering, and gaps are formed between the core and the plunger, and between the sub-yoke and the armature, so that the return speed of the armature is improved. High printing speed can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the wire type dot printer head according to the present invention, FIG. 2 is a sectional view of the wire unit, and FIG. 3 is an electromagnet unit. 4 shows an electromagnetic coil, a is a sectional view, b is a front view, and FIG. 5 is an armature unit, a is a sectional view and b is a front view. 11: wire, 21: main yoke, 22: centering, 23: core, 24: coil, 32: armature, 33: sub yoke, 34: plunger.

Claims (1)

[Claims] 1. A main yoke in which a plurality of cores are planted in a circular shape, and a coil is wound around each core, a sub-yoke that faces the main yoke and is disposed close to the tip of the core, and an outer yoke. The armature includes an armature whose end side is swingably provided on the sub-yoke, a plunger fixed to the armature facing the core, and a wire that is pressed and driven to protrude from the inner end side of the armature. In the wire type dot printer head, a centering ring made of a non-magnetic metal member is fixed to a portion of the main yoke inside the plurality of coil bobbins, and the operating stroke of the armature is such that the armature and the centering ring are connected in a attracted state. 1. A wire-type dot printer head characterized in that a gap is formed between the core and the plunger, and between the sub-yoke and the armature, the gap being regulated by collision with the core and the plunger.