JPH0478109B2 - - Google Patents

Description

[Detailed Description of the Invention] [Summary] The tip of the printing wire is pressed against the tip of the wire guide using a press plate having an arcuate recess so that the pressed armatures are wrapped on the same plane.

[Industrial application field]

The present invention relates to a printing head for a wire dot printer, and more particularly to a processing method for processing the stroke of a printing wire in accordance with the shape of a platen.

In recent years, various wire dot printers have been put into practical use as printers for various computer terminals, word processors, and the like.

Wire dot printers operate a print head to form dots using a print wire to print characters, so they can be used in many types of characters and are extremely convenient and economical.

In particular, the use of devices as end devices for computers is expanding, and there is a demand for improved performance and higher reliability of the devices.

[Conventional technology]

FIG. 3 is a plan view illustrating the outline of a wire dot printer to which the present invention is applied, FIG. 4 is a side sectional view of a printing magnet that constitutes the printing head in FIG. 3, and FIG. 5 is a side sectional view showing the printing head. 6A and 6B are side views showing a conventional printing head processing method.

The wire dot printer has a side frame 9 as shown in FIG.
A cylindrical platen 10 is rotatably supported.

A printing paper 11 is wrapped around the platen 10, and the printing paper 11 is wrapped around the sprockets 12a, 1.
2b, etc., in the direction of arrow A in the figure.

On the other hand, on the front of the platen 10 (lower in the figure),
A carrier 13 is slidably fitted into a guide shaft 15 provided parallel to the platen 10.
Further, the carrier 13 is similarly screwed into a feed screw 16 provided parallel to the platen 10.

The feed screw 16 is connected to a motor 19 via a belt 17 or the like, and therefore, the feed screw 16 moves the carrier 13 as indicated by arrows B-C in the figure depending on the forward and reverse rotation of the motor 19.

An ink ribbon cassette 20 is mounted on the carrier 13, and the ink ribbon cassette 20 houses an endless ink ribbon 20a with a part thereof exposed to the platen 10 side.

Further, a print head 21 is installed in the carrier 13 surrounded by an ink ribbon cassette 20, and the print head 21 is provided with a plurality of print magnets 21a that form prints depending on dots.

As shown in FIG. 4, the printing magnet 21a has a coil 2 wound around a core 1, and an armature 3 arranged so as to come into contact with the core 1.

A holding portion 3a having a printing wire 4 fixed to the tip thereof is attached to the armature 3, and the armature 3 is made of a magnetic material and is elastically supported by a leaf spring 5a.

The magnetic path sections 6a and 6b sandwich a permanent magnet 7 between them, and a magnetic path section 6d is arranged with a spacer 6c made of a magnetic material sandwiched therebetween, thereby forming a loop-shaped magnetic path together with the core 1 and the armature 3.

Therefore, when the printing magnet 21a is not operating, the armature 3 is attracted to the core 1 by the magnetic force of the permanent magnet as shown in the figure.

As shown in FIG. 5, in the printing head 21, a printing magnet 21a concentrates the printing wires 4 at the center, and the printing wires 4 are guided and aligned by a wire guide 8 protruding from the center.

The printing magnets 21a are arranged radially around the center line D.

With this configuration, when current is applied to the printing magnet 21a of the printing head 21 so that the NS pole of the permanent magnet 7 and the pole of the core 1 are opposite, the core 1 becomes an electromagnet and attracts the permanent magnet 7. It works to cancel out the force.

For this reason, the armature 3 springs upward in FIG. 4 due to the energy stored in the leaf spring 5a.

At the same time, the printing wire 4 also protrudes from the wire guide 8 shown in FIG.

In this way, while selectively driving the plurality of printing magnets 21a in the printing head 21, the printing head 21 is moved together with the carrier 13 in the direction of arrow B-C, and the printing paper 11 is moved as shown in FIG. Performs printing operation.

In order to set the stroke of the printing wire 4 during the manufacturing stage of such printing head 21, the stroke shown in FIG.
The processing shown in and b is performed.

(FIGS. 6a and 6b are views obtained by rotating FIG. 5 by 90 degrees.) That is, the magnetic path section including the printing wire 4, the armature 3, and the wire guide 8 of the printing head 21 shown in FIG. 6d and above (arrow E-F) are assembled together to form a printing wire assembly 22.

In this printing wire assembly 22, as shown in FIG. 6a, the tip of the printing wire 4 is connected to the wire guide 8.
It protrudes from the tip 8a by the stroke length arrow L.

In this state, there is no gap with the core 1 and the stroke is zero.

Therefore, in order to obtain a stroke, a flat pressing plate 23 is prepared and is pressed against the tip of the printing wire 4 as shown in FIG.
Push it all the way.

Then, the armature 3 is pushed down by the printing wire 4 and becomes oblique as shown. This oblique part is machined using a lapping machine or the like to make it flat as shown by the dashed line.

[Problem that the invention seeks to solve]

As explained above, the printing wire protrudes from the wire guide and prints depending on the restoring force of the leaf spring, but in the conventional processing method, the stroke of the printing wire is uniform, and the opposing platens are shown in Fig. 5. When the cross-sectional shape is circular with the curvature arrow R as shown in FIG.

[Means for solving problems]

FIG. 1 is a side view showing the printing head processing method of the present invention.

As shown in the figure, the tip of the printing wire 4 is pressed against the tip 8a of the wire guide 8 by the substantially arcuate concave portion 24a of the press plate 24. This problem is solved by the present invention which wraps the problem.

[Effect]

By providing the recessed portions in the pressing plate, the amount of pushing of the printing wire increases from the center to both ends.

For this reason, the stroke similarly increases from the center to both ends, and the protruding force of the printing wire when released also increases, making it possible to prevent blurred printing during printing.

〔Example〕

Figures 1 and 2 show one embodiment of the present invention, with Figure 1 being a side view showing the print head processing method of the present invention, and Figure 2 being a side view showing the state of the print head when it wraps. be.

In the figure, 24 is a pressing plate, and 24a is a recessed portion.

Identical parts are designated by the same reference numerals throughout the figures.

In order to set the stroke of each printing wire 4 of the printing head 21, which is made up of a plurality of printing magnets attached radially, the tip of the printing wire 4 is pressed against the tip 8a of the wire guide 8 with the press plate 23, and the stroke of the printing wire 4 is set. A method of manufacturing a printing head in which the armature 3 pressed down via the printing wire 4 is wrapped in the same plane has been described with reference to FIGS. 6a and 6b.

In the present invention, as shown in FIG. 1, in the same processing method as shown in FIGS. As shown in FIG. 2, the tip of the printing wire 4 is pressed against the tip 8a of the wire guide 8 in the recess 24a so that the center line of the wire 24a coincides with the printing head.

The printing wires 4 are lined up in two rows of 12 each and protrude from the wire guide 8, and FIGS. 1 and 2 are views seen from the direction in which the 12 printing wires are lined up.

As shown in FIG. 2, when each printing wire 4 is pressed by the pressing plate 24, each armature 3 is pushed down gradually from the center to both ends of the recess 24a of the pressing plate 24 via the printing wire 4. Become.

Therefore, if each armature 3 is machined into the same plane using a lapping machine or the like in such a state, the armature 3 will be cut gradually deeper from the center to both ends.

The cutting depth at which this armature 3 is cut means the size of the gap between the core 1 and the armature 3 when the printing head is assembled as shown in Fig. 5, and a large gap means a large stroke. do.

For this reason, in the printing head processed by the processing method of the present invention, the stroke of the printing wire 4 is gradually increased in the vertical direction compared to the left and right (axial length) direction of the platen 10.

When printing is performed using such a print head, a large amount of repulsive energy is accumulated in the print wire 4 during a large portion of the stroke, and the movement of the print wire 4 to match the curvature of the opposing cylindrical platen is caused. is obtained, and good printing is performed with uniform pressure. In addition, in the present invention, the curvature of the platen and the recess 2
4a, but by forming the curvature of the recess 24a to a predetermined value, the stroke of the printing wire 4 can be increased from the center to both ends, and the above-mentioned blurred printing can be avoided. This means that the resolution of the problem will be improved compared to the conventional method. Therefore, it is not necessary to match the curvature of the platen with the curvature of the recess 24a, and good printing can be achieved by setting the curvature of the recess 24a to a predetermined value.

〔Effect of the invention〕

As explained above, by applying the print head processing method of the present invention to the print head, the operation of the print head becomes rational, and the print quality can be improved without causing blurred print etc.
Its effects on industry are significant.

[Brief explanation of drawings]

FIG. 1 is a side view showing the print head processing method of the present invention, FIG. 2 is a side view showing the state of the print head when it wraps, and FIG. 3 is a plan view illustrating the outline of a wire dot printer to which the present invention is applied. 4 is a side sectional view of the printing magnet constituting the printing head of FIG. 3, and FIG. 5 is a side sectional view showing the printing head.
FIGS. 6a and 6b are side views showing a conventional printing head processing method. In the figure, 1 is a core, 2 is a coil, 3 is an armature, 3a is a holding part, 4 is a printing wire, 5a is a leaf spring, 6a, 6b, 6d are magnetic path parts, 6c is a spacer, 7 is a permanent magnet , 8 is a wire guide, 21a
is a printing magnet, 22 is a wire assembly,
23 and 24 are pressing plates, and 24a is a recessed portion.

Claims (1)

[Claims] 1. A plurality of armatures 3 arranged radially,
In the wire assembly 22, which includes a printing wire 4 held at one end of each of the armatures 3 and protruding from the tip 8a of the wire guide 8, the protrusion of the printing wire 4 is pushed in, and each armature is A method of processing a print head in which the predetermined surfaces of the print head 3 are ground to be the same plane, and the print head is formed so that when the print wire 4 is pushed in, the amount of push of the print wire 4 increases from the center to both ends. A printing head processing method characterized by: