JPH0482742A - Printing head - Google Patents

Abstract

PURPOSE:To reduce resistance in a rotary motion of an armature made for a printing operation by arranging a printing head of an impact type dot matrix printer so as to set a contact point between the armature and a hold spring near a fulcrum of the rotary motion of the armature. CONSTITUTION:An armature 13 has a projection 13a with a sector-shaped cross- section sticking out in a direction of a yoke 4 on both sides of a fulcrum part thereof with a support point of a rotary motion thereof pressed on the yoke 4 by a hold spring incorporated into an outer support 1. With such an arrangement, the armature 13 can make a stable motion without the deviation of the support point of the rotary motion of the armature 13 even by a fast operation thereof 13. Thus, as a contact point between the armature 13 and the hold spring 15 is set near the support point of the rotary motion of the armature 13, a moving value of the protrusion 13a by the rotary motion of the armature 13 can be minimized thereby enabling fast printing excellent in quality of print with a reduction in possible.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a print head used in an impact type dot matrix printer.

[Conventional technology]

Figure 6 (a> and (b) and (c) and (d)
1A and 1B are a plan view, a side view, a sectional view, and a perspective view showing an armature of an example of a conventional print head.

As shown in FIG. 6, a conventional print head used in an impact-type desoto matrix printer is provided with a protrusion 56a having a triangular cross section at the outer end of the surface of the armature 56 on the stopper 54 side. Armature 56 and stopper 5
By pressing the protrusion 56a of the armature 56 toward the yoke 44 by the support portion 57a on the outer periphery of the support rubber 57 provided between the armature 56 and the yoke 44, the armature 56
The armature 5 is made stable by pressing the part that becomes the fulcrum of the rotational movement of the armature 5 against the yoke 44 to prevent the fulcrum from shifting.
6 rotational movements are performed.

[Problem to be solved by the invention]

As mentioned above, in order to stabilize the rotational movement of the armature, the printing surface of the conventional impact type dot matrix printer (
A cross-sectional or triangular protrusion is provided on the outer end of the surface (the surface opposite to the printing surface side), and by pressing this protrusion toward the yoke with the sabot l~com, the fulcrum of the rotational movement of the armature is made to the yoke. It's forcing me. When the armature hits the printing surface, it rotates around the above-mentioned fulcrum, and the protrusion of the armature moves due to the rotation, and because the distance from the fulcrum to the protrusion is long, it moves. The distance is great. The support rubber that presses the fulcrum of the armature so that it does not shift acts as a resistance to the movement of these protrusions, so conventional print heads
This has the disadvantage that the force with which the printing wire connected to the armature strikes the printing surface becomes weaker and the striking time becomes longer.

[Means to solve the problem]

The print head of the impact-type dot matrix printer of the present invention has a magnetic circuit composed of a yoke, a coil, and an armature, and prints by driving a print wire by the rotational movement of the armature and striking the print surface. In a print head that performs A plurality of hold springs are embedded in the outer support and press the protrusion of the armature toward the yoke at the other end thereof, respectively.

Further, the print head of the impact-type dot matrix printer of the present invention has a magnetic circuit composed of a yoke, a coil, and an armature, and the rotational movement of the armature drives the print wire to strike the print surface. In the print head that performs printing, a projection having a sector-shaped cross section is provided on both sides of the fulcrum part of the armature, and a groove formed of rubber and having the same radius as the radius of the circular arc part of the projection of the armature is formed by this groove. A plurality of support rubbers are provided corresponding to each of the plurality of armatures that press the protrusion toward the yoke.5 [Embodiment] Next, an embodiment of the present invention will be described with reference to the drawings. do.

FIGS. 1(a) and (b) are a plan view and a sectional view showing a first embodiment of the present invention, and FIGS. 2(a) and (b) are a hold spring and an armature of the embodiment shown in FIG. 1, respectively. FIGS. 3(a) and 3(b) are a plan view and a sectional view taken along the line A--A showing details of the outer support of the embodiment shown in FIG.

In FIG. 1, the head frame 5 has a cylindrical front portion protruding from the center, and inside the head frame 5 are
A plurality of printing wires 1 that reciprocate and intermediate guides 7 to 10 arranged in series for guiding the movement are accommodated. A main guide 6 is provided at the tip of the cylindrical portion of the head frame 5 to hold the printing wire 11 in a predetermined position. The drive unit that drives the reciprocating motion of the printing wire 11 includes a yaw 74 and a coil 3 that generates magnetic flux as a driving force.
It is becoming more and more. The armature 13 is positioned by the outer support 1 and the inner support 2, and the printing wire 11 is fixed to the tip of the armature 13 by brazing. The other end of the armature 13 is
It contacts the yoke 4 and serves as a fulcrum for its rotational movement.
The armature 13 is attracted by the magnetic flux generated by the coil 3 and rotates, thereby causing the printing wire 1
1 hits the printed surface. Immediately after this, the armature 13 returns to its original position by the force of the return spring 12, completing the series of operations. The initial position is the state before the armature 13 is attracted by the magnetic flux generated by the coil 3 for printing, and is in contact with the stopper portion of the stopper plate 14.

As shown in FIG. 3, the outer support 1 is molded and holds hold springs 15 at positions corresponding to each of the plurality of armatures 13. As shown in FIG. 2(a), the hold spring 15 has a bent shape, with its short side being held and its long side protruding toward the armature 13. (See Figure 1(b)). Armature 13
As shown in FIG. 2(b), the holding spring has a sector-shaped projection 13a on both sides of its fulcrum part, which protrudes in the direction of the yoke 4, and is incorporated in the outer support 1. 15, the fulcrum of the rotational movement is pressed against the yoke 4. By configuring like this,
The fulcrum of the rotational movement of the armature 13 is the armature 1
Its position does not shift even with the high-speed movement in step 3.
The armature 13 can perform stable motion. By providing the contact point between the armature 13 and the hold spring 15 near the fulcrum of the rotational movement of the armature 1B, the amount of movement due to the rotational movement of the protrusion 13a is reduced, so that the resistance generated is reduced.

FIGS. 4(a) and (b) are a plan view and a sectional view showing a second embodiment of the present invention, and FIGS. 5(a) and (b) are respectively a support rubber and an armature of the embodiment of FIG. 4. FIG.

The basic structure of this embodiment is the same as that of the first embodiment described above, and the parts corresponding to the hold springs are made of support rubber.

That is, in FIG. 4, the He/Sodo frame 25 is
The front part of the central part protrudes into a cylindrical shape, and inside this head frame 25, there are a plurality of printing wires 31 that reciprocate.
and an intermediate guide 27 arranged in series to guide the movement.
~30 are accommodated. A main guide 26 is provided at the tip of the cylindrical portion of the head frame 25 to hold the printing wire 31 in a predetermined position. The drive unit that drives the reciprocating movement of the printing wire 3 includes a yoke 24 and a coil 23 that generates magnetic flux serving as a driving force. The armature 33 is positioned by the outer support 21 and the inner support 22, and the armature 33
A printing wire 31 is fixed to the tip of the wire by brazing. The other end of the armature 33 contacts the yoke 24 and serves as a fulcrum for its rotational movement, and the armature 33 is attracted by the magnetic flux generated by the coil 23 and performs its rotational movement, thereby causing the printing wire 31 to rotate. Hit the printed surface. Immediately after this, the armature 33 returns to its original position by the force of the return spring 32, completing the series of operations. The initial position is a state in which the armature 33 is attracted by the magnetic flux generated by the coil 23 for printing, and is in contact with the stopper portion of the stopper plate 34.

As shown in FIG. 5(b), the armature 33 has protrusions 33a on both sides of its fulcrum portion, which protrude in the direction of the yoke 24 and have a sector-shaped cross section, and are made of rectangular parallelepiped rubber. Groove 35a of support rubber 35 (Fig. 5 (a>
(see), and the fulcrum of its rotational movement is pressed against the yoke 24. The groove portion 35a has an arcuate inner surface with a radius that is approximately the same as the radius of the arcuate portion of the protrusion 33a. The support rubber 35 has a height slightly higher than that of the outer support 21 and a width slightly narrower than the distance between two adjacent armatures 33, and is provided between the outer support 21 and the inner support 22. It is being The support rubber 35 is pressed by the stopper plate 34 to press the protrusion 33a of the armature 33 toward the yoke 24, thereby fixing the fulcrum of the rotational movement of the armature 33. With this configuration, the fulcrum of the rotational movement of the armature 33 does not shift its position even when the armature 33 moves at high speed, and the armature 33 can perform stable movement. Armature 3
3 and the support rubber 35 near the fulcrum of the rotational movement of the armature 33, the protrusion 33a
Since the amount of movement due to the rotational movement of is reduced, the resistance generated becomes smaller.

〔Effect of the invention〕

As explained above, the print head of the impact-type dot matrix printer of the present invention has a contact point between the armature and the hold spring or support rubber near the fulcrum of the rotational movement of the armature, thereby facilitating the printing operation. This has the effect of reducing resistance when the armature rotates. In addition, since the impact force of the printing wire is weakened and the impact time is shortened, there is an effect that it is possible to obtain printing with excellent printing quality and high speed printing.

[Brief explanation of the drawing]

FIGS. 1(a) and (b) are a plan view and a sectional view showing a first embodiment of the present invention, and FIGS. 2(a) and (b) are a hold spring and an armature of the embodiment shown in FIG. 1, respectively. 3(a) and (b) are a plan view and a cross-sectional view taken along line A-A of the embodiment of FIG. 1, and FIG. 4(a) and (b) are A plan view and a sectional view showing a second embodiment of the present invention, FIG.
) and (b> are respectively perspective views showing the support com and armature of the embodiment of FIG.
), (b), (c), and (d) are a plan view, a side view, a sectional view, and a perspective view showing an armature of an example of a conventional print head. 121・・・Outer support, 2・22・・・
・Inner support, 3・23...Coil, 4・
24・44・・・Yoke, 5・25・・・Head frame, 626・・・Main guide, 7~1
0.27-30... Intermediate guide, 11.31...
・Printing wire, 12・32... Return spring, 133356... Armature, 13a 33
a・56a・・・Protrusion, 14・34・・・・・・
Stopper plate, 15... Hold spring, 35, 57... Support rubber, 35a...
・Groove, 54... Stopper 57a...
・Support Department.

Claims (1)

[Claims] 1. A print head that has a magnetic circuit composed of a yoke, a coil, and an armature, and performs printing by driving a printing wire by the rotational movement of the armature and striking a printing surface. , protrusions having a fan-shaped cross section are provided on both sides of the fulcrum portion of the armature, an outer support molded on the outer periphery of the armature is provided for positioning the armature, and one end is provided inside the outer support. A print head comprising: a plurality of hold springs embedded in the plurality of armatures, each of which presses the protrusion of the armature toward the yoke at the other end thereof. 2. In a print head that has a magnetic circuit composed of a yoke, a coil, and an armature, and performs printing by driving a printing wire by the rotational movement of the armature and hitting the printing surface, the fulcrum part of the armature The plurality of parts are provided with protrusions having a fan-shaped cross section on both sides of the armature, and have a groove formed of rubber and having the same radius as the radius of the arc portion of the protrusion of the armature, and the groove presses the protrusion toward the yoke. A print head characterized by having a plurality of support rubbers corresponding to each of the armatures.