JPS59155062A - Dot printer head - Google Patents

Abstract

PURPOSE:To permit high-speed printing by lessening the equivalent mass of an armature by providing fixedly the edged plastic fulcrum to freely support armature in a vertically movable manner on one side of the attraction face of the core. CONSTITUTION:The fulcrum 20 of an armature 19 is formed on one side of the attraction face 16 of a core 13, and the distance l1 from the fulcrum 20 to the center of the core 13 is made smaller than that l2 from the fulcrum 20 to a needle 23. Therefore, the equivalent mass of the armature 19 is made smaller, high-speed printing is made possible, air gap is made smaller, and the magnetomotive forces of a bobbinless coil 14 and the magnetic force of a permanent magnet 12 are made smaller.

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD OF THE INVENTION This invention relates to a dot printer head.

Technical background of the invention and its problems Figure 1 shows the invention described in Japanese Unexamined Patent Publication No. 56-127462 as a conventional example. By the excitation action of the coil (4), the − side of the core (3) is set as the fulcrum (5).
There is a release type dot printer in which an armature (2) is actuated by the force of a leaf spring (6) and a needle (7) collides with a platen to print. The fact that the fulcrum (5) is located on the - side of the core (3) means that the distance from the fulcrum (5) to the center of the core (3) is the distance from the fulcrum (5) to the armature tip needle (force). Therefore, it is possible to perform high-speed printing by reducing the amount of paper (2 mm).Also,
The magnetic force of the permanent magnet (1) has a small air gap. However, the fulcrum (5) is the abutting edge of the armature (2) and core (3) made of magnetic material, and is inferior in durability.

It may be possible to prevent the deterioration of the fulcrum (5) by interposing a plastic film or the like between the attraction surface of the core (3) and the armature (2), but since the magnetic permeability will deteriorate, the permanent magnet (1) The magnetic force of the coil (4) and the magnetomotive force of the coil (4) must be increased.

Next, FIG. 2 and FIG. 3 show the invention described in Japanese Patent Application Laid-open No. 140118/1983 as another conventional example.
A dot printer in which a plastic fulcrum (8) is provided near the core (3) to support the armature (9), and the armature (9) is attracted to the core (3) by the excitation action of the coil (4) to perform printing. There is a head.

Since the fulcrum (8) is made of plastic material, its durability (
Increase. However, the shapes of the armature (9) and the fulcrum (8) are complicated and difficult to manufacture. Although it is possible to improve manufacturability by manufacturing the armature (9) from sintered metal, the magnetic permeability deteriorates due to the low density of the structure, and the volume of the armature (9) is low due to the low density of the structure. Must be washed. This increases the moment of inertia of the armature (9). Amateur (9) It is possible to increase the strength by completely forging, but the complexity of the shape makes it even more difficult to manufacture.

The mounting structure of the fulcrum (8) also has to be devised in consideration of positional issues and mounting strength.

Purpose of the Invention The present invention was made in view of the above-mentioned points, and it is possible to perform high-speed printing by reducing the equivalent mass of the armature, increase the durability of the fulcrum, and simplify the structure of the armature and the fulcrum, making it easy to manufacture. The purpose of this invention is to create a dot printer head that is capable of printing.

Summary of the Invention This invention reduces the distance between the fulcrum and the center of the core by forming a fulcrum on one side of the core, thereby reducing the equivalent mass of the armature, enabling high-speed printing, and reducing consumption.
The armature can be supported in a straight line by reducing force and by forming the fulcrum using plastic to increase durability.By forming the fulcrum directly on one side of the suction surface of the core, the armature can be supported in a straight line. , the surface facing the fulcrum of the armature can be made flat, and the shapes of the armature and the fulcrum are simple to facilitate manufacturing.

Embodiment of the Invention An embodiment of the invention will be described with reference to FIGS. 4 to 10. An annular yoke circle is fixed to the case (11).A donut-shaped permanent magnet (1 magnet) is fixed to the outer circumference of this yoke 0υ, and a plurality of cores (13) are fixed to the top surface of this permanent magnet (121). These cores (2)
The portion to which the bobbinless coil Q41 is attached has an L-shape with equal cross-sectional areas and a large area facing the mounting base with respect to the permanent magnet (L2).

One side of the outer side of the suction surface (16) of these cores u31 is chamfered (17), and furthermore, these cores (13)
The outer peripheral surface of the tube is covered with a high-strength plastic material such as PP8 containing carbon fiber. Therefore, on one side of the outside of the suction surface (16), there is formed an edge-shaped fulcrum made of plastic that supports the armature [9] in a straight line. This fulcrum (20) has a thicker plastin 22081 layer and is stronger by the amount of chamfering αD. The suction surface (16) is coated with plastic and then polished together with one side of the yoke circle. The armature 09) is made by fixing a pressed part υ made of silicon steel or the like and a pressed part 221 made of carbon steel. Although the plate thickness is made thinner to reduce the moment, the direction of the plate thickness is perpendicular to the direction of movement of the armature U →, so the strength is sufficient. has been done.

Next, install the needle guide (231) that holds the needle (231).
(to) and an armature (a guide holder 126) having an armature guide that guides both sides of L9. This guide holder (26) is provided with a magnetic body (5), and a presser plate 129) that presses one end of the armature spring (c) is screwed to the guide holder (26). The magnetic Q force is used to form a side magnetic path from both sides of the armature (l → is fixed.

In such a configuration, the armature (19) is attracted to the attraction surface (16) by the magnetic flux of the permanent magnet (2), and when the coil (1) is excited in a direction that cancels the magnetic flux of the permanent magnet α4, the armature (19) is attracted to the attraction surface (16) by the magnetic flux of the permanent magnet (2). is rotated about the fulcrum uO)'lz by the force of the armature spring (2), causing the needle 123 to collide with the platen. Bobbinless coil U (
Amateur u! j is a permanent magnet U
It returns to the magnetic flux of the force and comes into contact with the suction surface (L6) and stops. At this time, the armature α0 is moved to the core (19 side (31
) occurs as a fulcrum, but the excessive return movement of the armature shaft → can be prevented by the stopper (2).

The fulcrum of the armature 11 wing is formed on the suction surface (1ω-side) of the core u turbidity, so the distance 12 from the fulcrum (20) to the core f1 is
3) The distance to the center can be reduced to 4. As a result, it is possible to achieve high-speed printing by reducing the equivalent mass of the armature (i→), and by reducing the air gap, the magnetic force of the permanent magnet circle and the magnetomotive force of the bobbinless coil α force can be reduced. Save electricity.

Further, since the fulcrum (20) is formed of plastic tta, it is possible to prevent the core and the armature 9) from being worn out. This fulcrum point 4 is also formed on the - side of the suction surface t16) of the core pleasure 3), so the armature (19
) can be supported by a straight edge, and as a result, the surface of the armature 4 relative to the fulcrum (4) can be made flat, and the shape of the fulcrum (20) can also be simplified, making it extremely easy to manufacture. It is.

Furthermore, by covering the entire outer surface of the core with a plastic layer, it is possible to use a bobbinless coil (141) as the coil to reduce the overall size. 13) The bonding between the two parts is also strong.The chamfer (1'r) serves to prevent the plastic slip layer from slipping and also to reduce leakage of magnetic flux from the attraction surface α6).

Effects of the Invention Since the present invention is configured as described above, the equivalent mass of the armature can be reduced by bringing the fulcrum close to the center of the core, thereby enabling high-speed printing and reducing power consumption. Furthermore, since the fulcrum is made of plastic, durability can be increased, and by forming the fulcrum on one side of the suction surface of the core, the υ armature can be supported with a straight edge. Therefore, the shape of the armature and the fulcrum can be simplified and manufactured very easily.

[Brief explanation of drawings]

Fig. 1 is a longitudinal side view showing one conventional example, Fig. 2 is a longitudinal side view showing another conventional example, Fig. 3 is a perspective view of the amateur, and Fig. 4 is an embodiment of the invention. A longitudinal side view showing,
Fig. 5 is a longitudinal side view of a part of the armature, Fig. 6 is a side view of the core, Fig. 7 is a plan view of the core, Fig. 8 is a side view of the armature, and Fig. 9' is a side view of the armature. Plan-1
FIG. 10 is a longitudinal side view of the yoke and core showing the relationship dimensions among the fulcrum, armature, and core. 11... Yoke, 13... Core, 14... Bobbinless coil (coil), 16... Suction surface, 18...
Plastics, 19... Amateur, 2o... Fulcrum applicant Tokyo Electric Co., Ltd.'' Gozu and Z diagram l ■KonJ, I, I 9 countries planning to display JD, % JD

Claims (1)

[Scope of Claims] 1. A dot printer mid, characterized in that a plastic edge-shaped fulcrum is fixedly provided on one side of the suction surface of the core to which the coil is attached, to support the armature in an up and down manner. 2. Claim 1, characterized in that the outer surface of the core is covered with plastic to form a fulcrum on one side of the suction surface, and the coil attached to the core is a bobbinless coil.
Dot printer head as described in section.