JPS635954A - Electromagnetic printing mechanism - Google Patents

Abstract

PURPOSE:To enable the printing at a high speed by enabling the use of the armature spring high in spring constant, by a method wherein both sides of the armature spring are extended in the direction different from the moving direction of an armature and the opposed face for attracting the armature spring is provided to a side yoke. CONSTITUTION:An armature spring 30 is a cantilever plate spring. Its one end is fixed to a yoke 27 via a spacer 29 and a side yoke 28 and its free end is wider than the width of an armature block 31, which has the face 30a opposed to the face 28 of the side yoke 28 of which both sides fare extended in the direction different from the moving direction of the armature. In addition to the attractive force between a yoke 23 and the armature block 31, magnetic fluxes d, e flow between the opposed faces 30a, 28a of the armature spring 30 and the side yoke 28 and intensive attractive force likely to bring the armature block 31 onto the yoke side 23 works. Because the attractive force can be enlarged, the armature spring high in spring constant can be used. Then, the natural frequency of a vibration system can be raised and the printing at a high speed becomes possible.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electromagnetic printing mechanism having a side yoke used in a dot matrix printer.

[Prior art] Regarding the conventional electromagnetic printing mechanism with side yokes, the third
This will be explained using FIG. This type of printing mechanism usually has a configuration as shown in FIG. The permanent magnet 6 is sandwiched between a yoke 7 and a yoke 5, and a yoke 3 is coupled to the yoke 5 so as to face an armature block 11.

A coil 4 for operating the printing mechanism is wound around the yoke 3. - side armature spring 10 is a cantilevered leaf spring with one end connected to spacer 9 and side yoke 8
An armature block 11 is fixed to the free end of the armature spring 10, and a printing wire 1 is further connected via an armature arm 2. In addition, the side yoke 8 has a small gap (usually 0.1 mm to 0.0 mm) with both sides of the armature block 11.
．． 2mm).

Next, the operation of the printing mechanism will be explained. Normally (when not in operation), the armature block 11 is attracted to the yoke 3 by the magnetic force of the permanent magnet 6, and the armature spring 10, whose free end is connected to the armature block 11, is bent as shown in FIG. Next, when current is applied to the coil 4 as required, the magnetic force of the permanent magnet 6 is canceled out, and the energy stored in the armature spring 10, which has been bent, causes the armature block 11 to leave the yoke 3, and the armature A printing wire 1 connected to an armature block 11 via an arm 2 operates to print dots on a sheet of paper (not shown) through an ink ribbon.

Furthermore, the suction force that pulls the armature block 11 will be explained using FIG. 4. f, g in the figure.

h represents the magnetic flux emitted from the permanent magnet 6, the magnetic flux f flowing through the yoke 3 flows to the armature block 11, the - part returns to the permanent magnet 6 through the armature spring 10,
The magnetic fluxes g and h flow to the side yoke 8 through a minute gap and return to the permanent magnet 6. Here, it is well known that the attractive force acting between the yoke 3 and the armature block 11 is determined by the amount of magnetic flux flowing between the yoke 3 and the armature block 11.

[Problems to be Solved] As mentioned above, in the conventional electromagnetic printing mechanism, the attraction force is determined by the amount of magnetic flux flowing between the yoke 3 and the armature block 11, so in order to increase the attraction force, The contact area between the yoke 3 and the armature block 11 must be increased. However, since a print head is usually configured by arranging multiple printing mechanisms in a circle, there is a limit to increasing the contact area between the yoke 3 and the armature block 11, and therefore, with conventional printing mechanisms, the suction force is limited. Limited, high spring constant armature spring 10
Since it was not possible to use the oscillation system, it was not possible to increase the natural frequency of the vibration system, and as a result, it was not possible to realize a high-speed print head.

Solution to Problem E] The present invention has been made by focusing on the above-mentioned conventional problems, and has a small size, yet has a large suction force, and as a result, it is possible to use an armature spring with a high spring constant. The present invention aims to provide an electromagnetic printing mechanism that can thereby increase the natural frequency of the vibration system and enable high-speed printing.

Therefore, in an electromagnetic printing mechanism having a side yoke, the present invention extends both sides of the armature spring in a direction different from the slow movement direction of the armature, and provides the side yoke of the armature spring with an opposing surface for attracting the armature spring. The present invention provides an electromagnetic printing mechanism characterized by the following.

[Example] Next, an example of the present invention will be described with reference to FIGS. 1 and 2.

FIG. 1 is a side view showing an electromagnetic printing mechanism according to an embodiment of the present invention. The permanent magnet 26 is connected to the yoke 25 and the yoke 27.
A yoke 23 is coupled to the yoke 25 so as to face an armature block 31 as an armature.

Further, this yoke 23 has a coil 2 for operating the printing mechanism.
4 is wrapped. The - side armature spring 30 is a cantilever leaf spring, the - end is fixed to the yoke 27 via the spacer 29 and the side yoke 28, the free end is wider than the width of the armature block 31, and both sides of the armature Side yoke 2 extended in a direction different from the slow movement direction
It has a surface 30a opposite to the surface 28a of No. 8. An armature block 31 is coupled to the free end of this armature spring 30, and a printing wire 21 is further coupled via an armature arm 22. Further, the side yoke 28 is connected to the armature block 31 as shown in FIG.
The armature spring 30 maintains a small gap (approximately 0.1 to 0.2 mm) with both sides of the armature spring 30 and is deflected by the suction force of the yoke 23 when the printing mechanism is not operating (standby).
and the opposing surfaces of the side yoke 28 are arranged so as to be in contact with each other.

Next, the operation will be explained. Normally (when not in operation), the armature block 31 is moved to the yoke 2 by the magnetic force of the permanent magnet 26.
The armature spring 30, which is attracted to the armature spring 3 and whose free end is connected to the armature block 31, is bent as shown in FIG. Next, when a current is passed through the coil 24 as necessary, the magnetic force of the permanent magnet 26 is canceled out, and the armature block 31 leaves the yoke 23 due to the energy stored in the armature spring 30, which has been bent. A printing wire 21 connected to an armature block 31 via an armature arm 22 operates to print dots on a sheet of paper (not shown) through an ink ribbon.

Therefore, conventionally, the suction force worked only between the yoke 3 and the armature block 11 as described above, but in this embodiment, in addition to the conventional suction force, the suction force acts between the opposing surfaces 30a and 28a of the armature spring 30 and the side yoke 28 Also magnetic flux d, e
flows, the armature block 31 is connected to the yoke 23.
A strong suction force works to pull it to the side.

In this embodiment, the armature spring 30 and the side yoke 28 are in contact with each other when the printing mechanism is not in operation. Although the suction power is smaller, it can provide stronger suction power than conventional ones.

[Effect of the Invention 1] As explained above, the present invention provides an electromagnetic printing mechanism having a side yoke, in which both sides of the armature spring are extended in a direction different from the direction of slow movement of the armature, and the armature spring is attached to the side yoke. Since the electromagnetic printing mechanism is characterized by having a facing surface for armature spring suction, it is possible to provide a printing mechanism that is small but has a large suction force.Also, since the suction force can be increased, the spring constant can be reduced. It becomes possible to use a high armature spring, thereby increasing the natural frequency of the vibration system, which has the effect of enabling high-speed printing.

[Brief explanation of the drawing]

FIG. 1 is a side view of an electromagnetic printing mechanism according to an embodiment of the present invention, FIG. 2 is an enlarged sectional view taken along line A-A in FIG. 1, and FIG. 3 is a side view of a conventional printing mechanism. A side view, and FIG. 4 is an enlarged sectional view taken along line BB in FIG. 3. 21: Printing wire 22: Armature arms 23, 25, 27: Yoke 26: Permanent magnet 28: Side yoke 28a: Opposing surface 29 Ni spacer 30: Armature spring 30a: Opposing surface 31: Armature block

Claims (1)

[Claims] An electromagnetic printing mechanism having a side yoke, characterized in that both sides of the armature spring are extended in a direction different from the slow movement direction of the armature, and opposing surfaces for armature spring attraction are provided on the armature spring and the side yoke. Electromagnetic printing mechanism.