JPS6253843A - Printing head - Google Patents

Abstract

PURPOSE:To permit the temperature of a coil to be lowered by setting a boss- like electric heating element of good heat conductivity in proximity to the inside of the coil of an electromagnetic mechanism for driving wires. CONSTITUTION:In making printing by the printing head, electric current is selectively supplied to the coil 26 of each electromagnetic mechanism. Hereupon, an armature 27 facing the coil 26 is moved in a rocking manner against the force of a rubber 37 for restoration and attracted by the opposite iron core 25, and printing is made by wires 32 whose one ends are connected to the armature 27. Although heat is produced in the coil 26 during the printing period, the heat of the coil 126 is transmitted from a conductor 23 to a casing 21 with good efficiency and released since the conductive 23 having good heat conductivity is provided and fixed in contact with the casing 21 in proximity to the inside of the coil 26.

Description

[Detailed Description of the Invention] [Summary] The purpose of the present invention is to improve the heat dissipation effect of a wire dot print head. This objective is achieved by disposing a boss-shaped electric heating member made of a material such that the heat generated by the coil is transmitted to the electromagnet mechanism mounting member through this heat transfer member.

[Industrial application field]

The present invention relates to the structure of a print head for a wire dot printer.

The print head of a wire dot printer has multiple wires, each driven by an electromagnetic mechanism.
By activating an electromagnet mechanism corresponding to a predetermined wire, the wire is made to protrude toward the printing surface to perform printing.

[Conventional technology]

A conventional printhead of this type is shown in FIG. In the figure, l is a mounting member, 2 is a print head, and 3 is a carrier. The mounting member 1 is fixed to the carrier 3 and moves together with the carrier 3, which is guided by guide bars 4 and 5 and driven in a direction perpendicular to the plane of the drawing. The print head 2 includes a plurality of electromagnetic mechanisms 6. Each electromagnet mechanism 6 includes an iron core 7, a coil 8 wound around the iron core 7, and an armature 9, and is provided in a predetermined arrangement in the circumferential direction. The iron core 7 of each electromagnetic mechanism is fixed to a common yoke 10, and the yoke 10 is connected to a frame 11 connected to the mounting member 1.
is fixed. Further, one end of a printing wire 12 is connected to the armature 9 of each electromagnetic mechanism.

When the coil 8 of each electromagnet mechanism is not energized, the armature 9 of each electromagnet mechanism is energized by the spring 13,
The cover 14 of the frame 11 is attached to the cover 14.

During printing, the coils 8 of each electromagnetic mechanism are selectively energized. As a result, the armature 9 of the electromagnetic mechanism whose coil is energized is attracted to the opposing iron core 7 against the biasing force of the spring 13, and the wire 12 whose one end is connected to the armature 9 is attached to the end surface of the mounting member 1. Printing is performed by protruding from 16.

[Problem that the invention seeks to solve]

In the conventional printing machine having such a configuration 1 effect, the heat generated in the coil 8 by energization is transferred to the iron core 7. The heat is transmitted to the frame 11 via the yoke 10, and the heat is transmitted to the carrier 3 via the mounting member 1, where it is radiated. That is, the heat generated in the coil 8 is transferred to the iron core 7. Since the heat is transmitted through the yoke 10, it is not efficient, and the heat dissipation effect is reduced accordingly.

[Means for solving problems]

An object of the present invention is to provide a print head that can solve the above-mentioned problems, and as a means for that purpose, as shown in FIG. It adopts a configuration in which it is placed close to the inside of the coil of the drive electromagnet mechanism. This heat transfer member is fixed in contact with a mounting member that couples the electromagnet mechanism.

[Effect]

The heat generated by the coil is efficiently transferred from a heat transfer member disposed close to the coil directly to the mounting member and dissipated, thereby significantly reducing the coil temperature.

〔Example〕

The invention will now be described in detail with reference to FIG.

FIG. 1 is a side view of a print head according to the present invention, in which 2 is a housing (mounting member), 22 is an electromagnetic mechanism, 23 is a heat transfer member, and 24 is a rubber cover.

The casing 21 is made of a material with good thermal conductivity, such as an aluminum alloy, and is attached to a carrier (not shown).
It is movable with the carrier.

The electromagnetic mechanism 22 includes an iron core 25, a coil 26 wound around the iron core 25, and armatures 27, and a plurality of armatures are provided in a predetermined arrangement in the circumferential direction. The iron core 25 of each electromagnet mechanism is fixed to a common yoke 28, and the yoke 28
is fixed to a frame (mounting member) 29, supporting each armature 27 in a swingable manner.

The heat transfer member 23 is a boss-shaped member made of a material with good thermal conductivity such as aluminum or copper, and the boss portion 30 is arranged close to the inside of the coil 26 of each electromagnet mechanism, and the flange thereof The portion 31 is fixed in direct contact with the housing 21. The above-mentioned electromagnet mechanism 22 is connected to this heat transfer member 2
3, and the installation procedure is as follows.

When installing the electromagnet mechanism, first yoke 28.
The frame 29 is fitted to the outer periphery of the boss portion 30 of the heat transfer member 23. In this case, the printing wire 32, one end of which is connected to each electromagnet IR structure (7) 7, is attached to the housing 21, etc. Guide and support. And in this state,
The screw 34 inserted into the pressing plate 33 is inserted into the boss portion 3 of the heat transfer member.
When the yoke 28 is screwed onto the bottom wall 35 of the elastic member 36. The armature recovery rubber 37 is pressed through the armature 27 and the frame 29
is fitted to the back side of the flange portion 31 of the heat transfer member.

The installation of the electromagnet mechanism as shown in the figure is completed by pressure contact. In this case, the yoke 28 is accurately positioned in the circumferential direction by engagement with the positioning pin 38 fixed to the heat transfer member 23, and the wire connection side end of the armature 27 is connected to the press plate 33 by a rubber plate. Adjacent stopper 40 via 39
As shown in the figure, it is locked and separated from the iron core 25.

The rubber cover 24 is removably fitted into the frame 29 and covers the electromagnet mechanism 22.

41 is an insulating plate made of rubber or the like.

When printing is performed using the gutter, the coils 26 of each electromagnetic mechanism are selectively energized as in the conventional case. As a result, the armature 27 facing the energized coil 26 swings against the urging force of the restoration rubber 37 and is attracted to the opposing iron core 25, and printing by the wire 32 whose one end is connected to the armature 27 will be held.

The coil 26 generates heat during this printing, but in the present invention, a heat transfer member 23 with good heat conduction is provided close to the inside of the coil 26, and the heat transfer member 23 is in contact with and fixed to the housing 21. Therefore, the heat generated in the coil 26 is efficiently transmitted from the heat transfer member 23 to the casing 21 and the carrier, and is dissipated.

Note that, as in this example, each electromagnet mechanism 22 and frame 29.
If silicone rubber 42 is filled between the heat transfer members 23, the heat generated in the coil 26 is better transferred to the heat transfer members 23, and the cooling effect is further improved.

〔Effect of the invention〕

As described above, according to the present invention, the heat generated by the coil is efficiently transmitted to the mounting member via the heat transfer member and dissipated, so that the coil temperature can be lowered.

[Brief explanation of drawings]

FIG. 1 is a side view of a print head showing an embodiment of the present invention, and FIG. 2 is a side view showing an outline of a conventional print head. In the figure, 21 is a housing (mounting member), 22 is an electromagnetic mechanism, 23 is a heat transfer member, 25 is one misalignment, 26 is a coil, 27 is an armature, 2nd is a yoke, 29 is a frame (mounting member), and 32 is a wire.

Claims (1)

[Scope of Claims] A printhead including a plurality of electromagnetic mechanisms coupled to a mounting member and a plurality of wires driven by each of the electromagnetic mechanisms, the coils of each of the electromagnetic mechanisms being selectively energized. In a wire dot printer that prints by activating the armature corresponding to the coil and protruding the wire connected to the armature, a boss-shaped heat transfer member made of a material with good heat conduction is attached to each of the electromagnetic mechanisms. A print head characterized in that the heat transfer member is disposed close to the inside of a coil, and is fixed in contact with the mounting member.