JPS599062A - Print head - Google Patents

Abstract

PURPOSE:To provide a compact size print head which is easy to assemble and capable of printing at a high speed by such an arrangement wherein an iron core is arranged inside a yoke which forms the fulcrum of an armature with its attracting surface faced to the end of a guide, and the armature is arranged in front of the iron core which is the side of the guide. CONSTITUTION:Outside a yoke 8, an armature 11 extended in the direction of its center is arranged, being positioned close to the attracting surface of an iron core 10 on which an excitation coil is wound around. The armature 11 is supported by the yoke 8 and it is able to rotate around the supporting point which is used as a fulcrum. The armature 11 is brought to contact with a return spring 13 installed to the interior of a guide 12. The end of the armature 11 is connected to a print wire 14 supported by the guide 12. Said return spring 13 is formed by providing grooves on a circular plate spring and each vane divided by said groove is independently brought to contact with each of armatures 11 arranged in the direction of circumference.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present inventor uses electromagnetic force to move the movable parts of the armature, etc. in KmL,
Regarding the printing bed used for printing.

[Technical background of the invention]

No. 11 shows an example of the structure of a conventional print head of this type. An iron core 2 is arranged inside the yoke 1, and this iron core 2
An excitation coil 3 is wound around.

An armature 4 extending toward the center is disposed close to the iron core 2), and the end of the armature 4 on the center side is in contact with the printing wire 5. Further, the vicinity of the end of the armature 4 on the side of the iron core 2 is supported by a yoke l, and is rotatable about this as a fulcrum. The printing wire 5Fi is guided and held by the guide 6. When the excitation coil 3 is energized and excited, the armature 4 becomes the iron core 2f.
It is driven by being attracted by lIl, and prints by pushing out the printing wire 5 that is in contact with the tip toward the tip of the guide 6.

[Problems with background technology]

In the conventional example described above, since the iron core 2 is arranged inside the yoke 1 (one hole in the center), there is a drawback that the outer size of the print head becomes large. This increase in the external size of the print head increases the distance fJ of the movable parts such as the armature 4, making it unsuitable for high-speed driving, and has the disadvantage of making it difficult to print ('+i4 m).Also, the tip of the guide 6 Since the armature 4 was arranged behind the iron core 2, which is the farther side, the total length of the printing wire 5 became longer, and the number of guide parts to prevent buckling of the printing wire 5 was increased, making assembly easier. There were also aggravating flaws.

(Object of the Invention) In view of the above-mentioned drawbacks, an object of the present invention is to provide a print head that is small in size, capable of high-speed printing, and has good assemblability.

[Summary of the invention]

In the present invention, an iron core wrapped with a coil is placed inside a yoke that forms the fulcrum of the armature with its suction surface facing toward the tip of the guide, and the armature is placed in front of the iron core on the guide side. The above object is achieved by shortening the longitudinal dimension of the armature and shortening the wire connected to it.

[Embodiments of the invention]

FIG. 2 is an explanatory diagram showing the structure of an embodiment of the print head of the present invention. An iron core 10 around which an excitation coil 9 is wound is arranged outside the yoke 8, and an armature 11 extending toward the center is arranged close to the attracting surface of the iron core 10.

This armature 11 is supported by the yoke 8 and is rotatable about this support point as a fulcrum. A return spring 13 attached to the inside of the guide 12 is in contact with the armature 11. Also, amateur 1
1 is connected to a printing wire 14, and this printing wire 14 is held by the guide 12. Note that an armature stopper 15 is provided close to the end of the iron core 1 (Nt14) of the armature 11.

FIG. 3 is a diagram showing details of the return spring 13. Predetermined for a single circular leaf spring! ! A cut upper blade portion 16 is formed by cutting a groove with J 111n and is partitioned by the groove for each armature 11 arranged in the circumferential direction.
It is constructed so that it abuts independently. In addition, the second
A plurality of armatures, 11 of which are shown in the figure, are arranged in the circumferential direction.

Next, the operation of this embodiment will be explained. When the excitation coil 9 is energized by an external drive signal, the armature 11 is attracted in the direction of the iron core 10, so the armature 1 on the anti-attraction side]
The printing wire 14 connected to the end of the ribbon is pushed out toward the platen 17 in the opposite direction to the suction direction, and prints on the paper via the ribbon.

After the excitation coil 9 is no longer energized, the return spring 1
3, the armature 1lf1 returns to its original position, and at the same time, the printing wire 14 also returns to its original position.

and (7) [1 amateur flit amateur asto spit 1
5 and returns to the normal position. Further, the wire guide 12 has a function of aligning the printing wires 14 in a predetermined array toward the tip. , f: Characters are printed by repeating the operations described below.

According to this embodiment, since the armature 11 is disposed inside the iron core 10, the longitudinal dimension of the armature 11 can be shortened, so that the entire print head can be downsized.

Further, as the outer size of the head becomes smaller, drive parts such as the armature 11 become smaller and their mass decreases, so the drive parts can be driven at high speed and high-speed printing becomes possible. Further, the driving power can be reduced at the same printing speed as the conventional printing speed.

Also, the suction surface of the iron core 10 is on the platen 17 side (guide 12
(rule), the armature 11 is also disposed on the side of the print wire 17, and the length of the printing wire 14.

Since it is possible to shorten the length of the printing wire 14 and to omit a guide component for preventing buckling of the printing wire, the assembling efficiency can be improved completely, and high-speed printing can be performed using the short printing wire 14 in the same manner as described above. Furthermore, since the OJ return spring 13 is held by the wire guide 12, no special spring holding device is required, which improves the ease of assembly of this part and contributes to cost reduction.

〔Effect of the invention〕

As described above, the print head of the present invention has the excellent effect of being compact, capable of high-speed printing, and improving assembly efficiency.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram showing an example of the structure of a conventional print head;
The figure is an explanatory diagram showing the structure of one embodiment of the print head of the present invention, and FIG. 3 is a plan view showing the detailed structure of the return spring shown in FIG. 2. 8... Yoke 9... Excitation coil 10...
・Iron core 11...Amateur 12...Guide 13...Return spring 14...Printing wire agent Patent attorney Noriyuki Chika (and 1 other person) Figure 1 Figure 2 Figure 5 Figure 3

Claims (2)

[Claims] (1) An armature whose fulcrum is an iron core around which an excitation coil is wound and a yoke that connects and supports this iron core, and whose one end is disposed close to the attraction surface of the iron core; It has a printing wire connected to the other end of the armature and a guide member that holds this printing wire, and the armature is attracted to the iron core by energizing the excitation coil to cause the printing wire to protrude from the tip of the guide member to print. In the print head, the iron core is disposed outside the yoke, the suction surface of the iron core is disposed toward the tip of the guide member, and the armature is provided toward the tip of the guide member of the iron core. print head. (2) By inserting multiple Sts in the radial direction into one disc-shaped leaf spring to partition the member, the outer peripheral part continues to the current state and forms multiple blade-like springs in the direction of the center of the spring. A return spring consisting of the following is disposed between the rear end surface of the guide member mJ and the armature, the outer circumference of the return spring is fixed to the guide member, and the inner circumferential end of the blade is fixed to the armature. The print head according to claim 1, wherein the print head is in contact with the print head.