JPH0141506B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Technical Field of the Invention The printing head armature forming method of the present invention achieves good suction surface precision between the armature and core of a release type printer and guarantees high quality of printing. Regarding amateur processing methods.

(b) Technical Background Figure 1 is an overall overview of an open-release serial printer. A frame 1 rotatably supports a platen 2 with its longitudinal direction as an axis, and is intermittently rotated by a motor (not shown) via a gear 3. The paper 4 is attached to sprockets 5 provided at both ends of the platen 2.
a and 5b, and is sent by the rotation of the platen 2. The carrier 6 is guided by a rotating feed screw 8 via a belt 10 from a guide shaft 7 and a space motor 9, and moves in space along the platen 2 in the direction of arrow A. The printing head 11 is mounted on the carrier 6, and is provided with a plurality of printing wires 26 and an electromagnetic mechanism for driving them.The electromagnetic mechanism is selectively driven in synchronization with the movement of the carrier 6. The ink ribbon 13 is built into the ink ribbon cassette 12, and is connected to the print head 11 and the paper 4.
Run between.

FIG. 2 is a side sectional view of print head 11 in FIG. An electromagnet generated by coil excitation composed of a wound core 21 and a permanent magnet 20 are provided in the same magnetic path, and within this magnetic path, one end of the armature 25 is held on a cantilever by supplementing with a spacer 23, and the other end is held free. The printing wire 26 is fixed to the end side, and the free end is normally attached to the core 21 by bending the gap G caused by the spacer 23 using the magnetic attraction force of the permanent magnet 20, and when printing, the coil 22 is energized. By doing so, the attractive force of the permanent magnet 20 is cut off and the amateur 2
5 separates from the core 21 due to the elastic force caused by the bending. With this operation, the printing wire 26 rapidly approaches the platen 2 and hits the platen 2 hard through the ink ribbon 13 and the paper 4. When the ink from the ink ribbon 13 adheres to the paper 4, printing is performed. .
Next, when the coil 22 is de-energized, the printing wire 26 whose free end is attracted to the core 21 by the attractive force of the permanent magnet 20 returns to its original position.

(c) Conventional technology and problems Figure 3 shows amateur 25 when it comes to conventional technology.
FIG. 3 is a diagram of an adsorption state between the core 21 and the core 21 . Amachiyua 2
5 is attracted to the core 21, but when it comes into contact with point a indicated by the dotted line circle in the figure, if the spring constant of the armature spring part (the reverse concave part of the armature arm in the figure) is stiff, the dotted circle mark
A gap remains at point a' and magnetic flux leaks, weakening the attraction force of the armature and weakening the striking force of the printing wire 26 against the platen 2 when the attraction is released.
There was a drawback that the print quality deteriorated. On the other hand, when the spring constant of the armature is weak, the dotted circle mark a' is strongly attracted, resulting in excessive deformation of the bent shape of the armature 25, which causes the problem of early brittle fatigue of the armature material.

(d) Object of the invention The object of the invention is to provide an amateur molded article that solves the above-mentioned problems.

(e) Structure of the Invention The printing head amateur molding method of the present invention which achieves the above-mentioned object has a plurality of pieces protruding from the entire periphery toward the center, each of which has a spring portion corresponding to the protruding position. An armature serving as a suction part and a printing wire attachment part is placed, and the peripheral part of the armature is fixed together with a side magnetic path member via a spacer to an electromagnetic mechanism consisting of a core equipped with a permanent magnet and a winding ring that forms a magnetic path. In positioning the gap between the armature and the core of a print head of a release type printer in which the armature is attracted to the core by the attraction force of the permanent magnet, a predetermined amount of stroke is applied to the suction portion in the direction of a predetermined reference plane. After giving and holding,
A gap between the scraped surface and the core when the stroke is returned is determined by scraping off a portion of the suction part that exceeds the predetermined reference plane.

(f) Examples of the invention will be described in detail below using figures. FIG. 4 is an explanatory diagram showing one embodiment of the present invention, in which A and B are explanatory diagrams when the gap between the armature and the core is different in the initial state, and C in the diagram is the state after molding. It is an explanatory diagram. In the figure, 25 is amateur, 21 is core, S
is the stroke, H-H' is the reference plane, d1, d2 are the protruding lengths from the reference plane H-H', D1, D2
is the gap before forming, D is the gap after forming, b
1 and b2 are the target parts to be scraped off.

In Fig. 4 A and B, the gap D1 before molding,
Although D2 is different, the predetermined stroke S(A,
The lower part b of the armature 25 is pushed below the reference plane H-H' by applying an external force (the same stroke amount for both b)
If only 1 and b2 (b1>b2 in the figure) are removed by polishing, the stroke S
The gap D obtained when removing is the same gap D in both A and B. That is, in case A, the gap D1 is small, so the portion (scraped portion b1) that exceeds the reference plane H-H' is large due to the predetermined stroke S, while in B, the gap D2 is large, so the predetermined stroke S
The part exceeding the reference plane H-H' (scraped part b
2) becomes smaller, so the gap D after molding becomes the same value in A and B mentioned above.

At this time, the value of stroke S is amateur 2.
5 as long as the spring constant provides the design value. Therefore, in this embodiment, a predetermined stroke is given by external forces P and P', but the external force shown in FIG. According to the relationship diagram between P and stroke S, the stroke S or external force P may be any value (stroke or external force) that provides a predetermined spring constant k.

For the scraping operation of the target parts b1 and b2 that are lower than the reference plane by applying the above-mentioned stroke, it is possible to apply the stroke while maintaining the external force P, for example, using a jig (not shown), or by applying the stroke. It is also possible to braze the entire armature while it is still in place and then scrape it off. After being shaved off by brazing, the solder material is melted and removed to set a predetermined gap D.

(g) Effects of the Invention According to the printing head armature forming method of the present invention, when assembling the armature to the printing head, even if the armature material is individually warped before molding, it can be formed into a uniform core. Gap can be guaranteed,
The striking force of the printing wire against the platen when the suction is released becomes uniform, which has a great effect in printing good characters on paper.

[Brief explanation of drawings]

Fig. 1 is an overall overview of the release type printer, Fig. 2 is a side sectional view of the printing head, Fig. 3 is a diagram of the suction state of the armature according to the prior art, and Fig. 4 is an explanatory diagram of the armature forming method of the present invention. FIG. 5 is a diagram showing the relationship between the external force applied to the armature during molding and the stroke. In the figure, 21 is the core, 25 is the armature, S is the stroke, H-H' is the reference plane, P and P' are the external forces,
D1, D2, D are gaps, d1, d2 are protrusion widths from the reference plane, and b1, b2, b1', b2' are parts to be scraped off.

Claims (1)

[Scope of Claims] 1. A plurality of pieces protrude from the entire periphery toward the center, each of which has an armature that serves as a spring part, a suction part, and a printing wire attachment part, corresponding to the protruding position,
The peripheral part of the armature is fixed together with a side magnetic path member via a spacer to an electromagnetic mechanism consisting of a core equipped with a permanent magnet forming a magnetic path and a winding ring, and the armature is attached to the core by the attractive force of the permanent magnet. In positioning the gap between the armature of the print head of the released type printer and the core, the suction section is given a predetermined amount of stroke in the direction of the predetermined reference surface and held, and then the suction section exceeds the predetermined reference surface. By scraping off the
A method for forming an amateur print head, which comprises positioning a gap between the scraped surface and the core when the stroke is returned. 2. The printing head amateur molding method according to item 1, characterized in that the holding after the stroke is applied is solidified with a solder material.