JPS6216829B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a printing hammer, and more particularly to a printing hammer for a printer device used as an input/output device for an information processing device.

In general, line printers, serial printers, etc., which are printing devices for electronic computers, have a configuration in which an electrical signal is applied to a printing hammer drive circuit to cause the printing hammer to repeat the operation of stamping the printing surface, thereby continuously performing printing operations. It is becoming. As this type of printing hammer, a moving coil type, a clamper type, a plunger type, a spring charge type, and the like are used.

FIG. 1 shows a conventional spring-type printing hammer of this type. In FIG. 1, a yoke 2 around which a coil 1 is wound is arranged so as to come into contact with a permanent magnet 3. This permanent magnet 3
and the yoke 2 are connected to a spring 5 by a screw 4.
A printing pin 6 is fixed to this spring 5.

In such a conventional printing hammer, when no current flows through the coil, the magnetic flux generated from the permanent magnet 3 causes the upper end of the spring 5 to which the printing pin 6 is fixed to the magnetic pole surface at the tip of the yoke 2. be attracted. In this state, when a current is applied to the coil 1 in a direction that cancels out the magnetic flux generated by the permanent magnet 3, the attraction is canceled. As a result, the spring 6 returns to its free position, and the printing pin 6 collides with the printing surface (not shown) to print a predetermined character. In this case, in order to achieve high-speed printing, it is generally considered to increase the mechanical resonance frequency of the spring 6 to increase the response wave number of the spring. However, as the resonant frequency is increased, the stiffness of the spring is typically increased correspondingly, and as a result, the suction force required to deflect the spring required for the printing operation must be significantly increased. On the other hand, the magnetic flux that is the source of the attractive force generated by the permanent magnet 3 has its own upper limit within a predetermined dimension due to the limitations of the magnetic circuit formed by the yoke 2. Therefore, the conventional structure shown in FIG. However, the disadvantage was that faster printing operations could not be achieved.

SUMMARY OF THE INVENTION An object of the present invention is to provide a printing hammer in which a recess is provided in the yoke to increase magnetic flux in order to solve the above-mentioned conventional problems.

The printing hammer of the present invention includes a plate spring having a printing pin at one end, and an opening toward the plate spring at one end opposite to the one end of the plate spring. a yoke provided with a U-shaped recess; a permanent magnet fixed between the other end of the yoke and the other end of the plate spring; and a permanent magnet wound around the one end of the yoke. the one end of the plate-shaped spring is brought into attraction contact with the bottom surface of the recess of the yoke by the magnetic flux of the permanent magnet to store an elastic force, and responds to energization of the coil. The magnetic flux generated by the magnetic flux cancels the magnetic flux of the permanent magnet, so that the one end of the plate spring separates from the bottom surface of the recess of the yoke to perform printing.

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 2 is a schematic configuration diagram showing the first embodiment.
In FIG. 2, a suction end 12a is formed at one end of the yoke 12 around which the coil 11 is wound.
A U-shaped recess 12a ₁ is formed in the yoke 12, and the yoke 12 is arranged so as to come into contact with the permanent magnet 13. The permanent magnet 13 and the yoke 12 are fixed to a spring 15 by a screw 14. In this case, the spring 15 is attracted to the bottom of the recess _12a1 of the yoke 12, and the spring 15
A printing pin 16 is fixed to.

3A and 3B are cross-sectional views of the suction portion between the spring 15 and the yoke 12 in the first embodiment, and FIGS. 3C and 3D are the conventional spring 5 shown in FIG. 1. 12b and 2b are magnetic fluxes perpendicular to the attraction surface, and 12c is a magnetic flux flowing on both sides of the spring 15. FIG.

Figure 4 shows the characteristics. In FIG. 4, X ₀ is the distance between the yoke 12 and the spring 15, F ₀ is the force generated in the spring 15 when the spring 15 is deflected by x ₀ , and a is the attraction force curve of the present invention shown in FIG. 2. , b are the conventional attraction force curves shown in FIG. 1, and c and d are straight lines indicating spring stiffness (F ₀ /x ₀ ).

In the first embodiment of the printing hammer having the above configuration, when no current flows through the coil 11, the spring 15 is attracted to the attraction end 12a of the yoke 12. In such a state, as shown in FIG. 3A, in addition to the magnetic flux 12b that is almost perpendicular to the attraction surface, magnetic flux 12 flows in from both sides of the spring 15.
c exists. However, in the conventional FIG. 3B, there is no magnetic flux corresponding to the magnetic flux 12c. Further, when the attraction force is released by passing a current through the coil 11, FIG. 3B of the present invention and FIG.
In both figures D, printing is performed by moving the springs 5 and 15 to the free ends in the same principle. Further, when the current in the coil 11 is cut off, the recess 12a ₁ of the yoke 12 begins to attract the spring 15. In this case, the third
As shown in Figures A and 3B, the attractive force exerted on the spring 15 due to the presence of the magnetic flux 12c is as shown in Figure 3C.
Also, compared to FIG. 3D, it effectively acts on the spring located at a relatively far position, and the suction force becomes high. That is, in FIG. 4, it is possible to make the suction curve a of the present invention relatively higher than the conventional suction curve b. Therefore, it is possible to increase the force generated in the spring 15 as shown in FIG.
Since the corresponding spring stiffness in Figures C and 3D can be increased from line c to line d, the resonant frequency of spring 15 can be increased.

FIG. 5 is a schematic configuration diagram showing a second embodiment.
In FIG. 5, the yoke 22 and the permanent magnet 23 each extend in the printing line direction. Each of the suction end portions 22a ₁ to 22 an formed by dividing the yoke 22 has a U-shaped recess 22 .
a ₁₁ to 22a ₁ n are formed, and such a yoke 22
is arranged so as to be in contact with the permanent magnet 23. The permanent magnet 23 and the yoke 22 are fixed to a spring 25 by a screw 24, and in this case, the spring 25 is attached to the recess 22a ₁₁ of the yoke 22.
The printing pins 26 are fixed to the _springs 25.

The second embodiment of the printing hammer according to the groove formation also exhibits the same functions and effects as the first embodiment shown in FIGS. 2 to 4. In this second embodiment, one line of character codes can be printed at the same time _.
A synergistic effect with the suction effect of ~22a ₁ n achieves high-speed printing operation.

As explained above, the present invention has the effect of enabling high-speed printing because the resonant frequency is increased by attracting a spring having relatively high stiffness due to an increase in the amount of magnetic flux.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram of the conventional printing hammer;
3A to 3D are cross-sectional views of the suction portion between the spring and the yoke in FIGS. 1 and 2, and FIG. FIG. 4 is an explanatory diagram showing the characteristics of the suction section in FIGS. 1 and 2, and FIG. 5 is a schematic diagram showing a second embodiment of the printing hammer according to the present invention. 11,21 ₁ to 21n...Coil, 12,22
... Yoke, 12a, 22a ₁ - 22an ... Suction end, 12a ₁ , 22a ₁₂ - 22a ₁ n ... Recess, 13,
23... Permanent magnet, 15, 25... Spring,
16,26 ₁ ~ n... Printing pin.

Claims (1)

[Scope of Claims] 1. A plate spring having a printing pin at one end; and an opening toward the plate spring at one end opposite to the one end of the plate spring. a yoke provided with a U-shaped recess; a permanent magnet fixed between the other end of the yoke and the other end of the plate spring; and a permanent magnet wound around the one end of the yoke. the one end of the plate-shaped spring is brought into attraction contact with the bottom surface of the recess of the yoke by the magnetic flux of the permanent magnet to store an elastic force, and responds to energization of the coil. The printing hammer is characterized in that the one end of the plate spring separates from the bottom surface of the recess of the yoke to perform printing by canceling out the magnetic flux of the permanent magnet.