JPS647872B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention biases a leaf spring with a permanent magnet, and excites a magnetic coil provided in a magnetic path of the permanent magnet to cancel the magnetic field of the permanent magnet, thereby biasing the biased spring. The present invention relates to a print head for a dot printer that releases a leaf spring and drives a print wire by the leaf spring.

This type of conventional print head for dot printers consists of, for one print wire, an armature that supports the print wire, a leaf spring that supports the armature, a permanent magnet that attracts the armature, and a magnetic field of the permanent magnet. It was equipped with one magnetic coil to cancel out the magnetic field, and one yoke to form a magnetic path. For this reason, the conventional print head for dot printers has the drawbacks of having a large number of parts, requiring a large number of assembly steps, being expensive, and being large.

There is also a structure in which the printed wire is bent into an L-shape and fixed to the leaf spring, but in this case, a bending moment is generated at the bending point at the time of impact, resulting in a loss of impact energy.

In order to eliminate the above-mentioned drawbacks, the present invention divides the central part of a ring-shaped leaf spring into multiple pieces radially, and fixes a linear printed wire to each of the divided pieces via an armature.
The above-mentioned N print wires and N armatures are integrated into one leaf spring, and the purpose is to provide an efficient, compact and lightweight print head for dot printers that suppresses loss of impact energy. Another object of the present invention is to provide a print head for a dot printer in which the materials and shapes of each part can be optimally selected.

FIG. 1 is a sectional view showing a print head for a dot printer, explaining the principle of the present invention, and FIG. 2 is an exploded perspective view of FIG. In FIGS. 1 and 2, 1 is a first plate forming a common magnetic path, and 2 is N pieces (N=2, 3, 4...) fixed to the plate 1 facing an armature 9, which will be described later. core,
3 is a ring-shaped permanent magnet that surrounds a magnet coil 4 and is fixed to the first plate 1, which will be described later;
5 is a second plate each having a hole 5a at a position facing the plurality of cores 2 to form a common magnetic path; 6 is a second plate that is fitted to each of the N cores 2; A spacer mounted on the plate 5 to provide a predetermined gap between the second plate 5 and a leaf spring 7 to be described later; 7 is a single leaf spring whose center portion is radially divided into N pieces 7a; Reference numeral 8 denotes a printed wire fixed to each of the N divided pieces 7a of the leaf spring 7 via an armature 9, which will be described later; 9 denotes the N divided pieces 7 of the leaf spring 7;
10 is a guide frame; 11 is a wire guide that is loaded at the tip of the guide frame 10 and guides the printed wire 8; the guide frame 10 and the wire guide 11 constitute a guide member; do.

The operation in the above configuration will be explained. First, when the magnet coil 4 is not energized, the armature 9 is attracted to the opposing core 2 by the magnetic force of the ring-shaped permanent magnet 3, so that the divided piece 7a of the leaf spring 7
are all biased towards said core 2. Next, when a desired magnet coil 4 is excited, the magnetic field generated in the magnet coil 4 cancels the magnetic field of the ring-shaped permanent magnet 3, so that the armature 9 is moved from the core 2 corresponding to the excited magnet coil 4. leaves. Therefore, among the divided pieces 7a of the plate spring 7, the excited magnet coil 4
The corresponding split piece 7a is released and drives the print wire 8. Thereafter, when the magnet coil 4 is deenergized, the released segment 7a of the leaf spring 7 is biased toward the core 2 again.

FIG. 3 is a partial perspective view showing one embodiment of the present invention. As shown in the figure, an armature 9a is fixed to each of the divided pieces 7a formed by dividing the central part of the leaf spring 7 radially, and a linear printed wire 8a is fixed to the armature 9a by welding or adhesive. ing. At this time, the straight printed wire 8a is located almost directly below the wire guide 11 (see FIG. 1), and is located directly below the armature 9a.
is fixed to the leading edge of the

With the configuration shown in FIG. 3 described above, the movement of the armature 9a caused by the energization and de-energization of the magnet coil 4 (see FIG. 1) can be directly transmitted to the printed wire 8a, and the loss of impact energy can be suppressed. can. In addition, the armature 9
Fixing the straight printed wire 8a to the leading edge of the armature 9a is facilitated by increasing the thickness of the armature 9a.

As explained above, according to the present invention, a straight printed wire is fixed to each divided piece of a leaf spring whose central part is radially divided into N pieces through an armature, so that N pieces of printed wire can be printed. The wire and N armatures can be integrally attached to one leaf spring, and by assembling the parts, the number of assembly steps can be greatly reduced, and an inexpensive and highly reliable printing head can be provided.

Additionally, by attaching a straight print wire to the leading edge of the armature, loss of impact energy can be suppressed and converted into printing power efficiently, which can be expected to be effective in reducing the size and weight of the printing head.

Furthermore, since the mechanical properties required of the leaf spring and the magnetic properties required of the armature can be considered separately, the material and shape can be optimized.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a printing head for a dot printer to explain the principle of the present invention, FIG. 2 is an exploded perspective view of FIG. 1, and FIG. 3 is a partial perspective view showing an embodiment of the present invention. . DESCRIPTION OF SYMBOLS 1...First plate, 2...Core, 3...Ring-shaped permanent magnet, 4...Magnetic coil, 5...
Second plate, 6... Spacer, 7... Leaf spring,
7a...Divided piece, 8,8a...Printed wire,
9, 9a... Armature, 10... Guide frame, 11... Wire guide.

Claims (1)

[Claims] 1. The central part of a ring-shaped leaf spring is radially divided into a plurality of divided pieces, each divided piece is biased by a permanent magnet, and an armature to which a printed wire is fixed is mounted on each divided piece. In a print head for a dot printer, the biasing split piece is released by energizing a plurality of magnet coils corresponding to each split piece to cancel the magnetic field of the permanent magnet, thereby driving a print wire. The wire is straight and fixed to the tip of the armature almost directly under the wire guide, the core of the magnetic coil is placed opposite the armature, and the permanent magnet is arranged in a ring shape surrounding all the magnetic coils. A printing head for a dot printer, characterized by: