JPS62161558A - Electrode head - Google Patents

Abstract

PURPOSE:To obtain an inexpensive electrode head having high resolving power and high reliability, by constituting the electrode head so that a large number of grooves are formed to the surface of a first electric insulating support and electrode needles are provided to respective grooves and the grooved surface of the first support is covered with a second electric insulating support to fill the gaps formed by the first and second supports and the electrode needles with a resin. CONSTITUTION:Grooves are processed to the surface of a first electric insulating support 101 and, as the material quality of the support, for example, a sintered body of hexagonal boron nitride or gypsum having softness imparting no damage to the surface of recording paper other than an electric insulating property is pref. used. Further, in a composite such as a resin, hexagonal boron nitride, calcium carbonate and talc etc. may be used as a filler and a second support 102 also has the same material quality. As an electrode needle, a coated copper wire is pref. from an aspect for preventing the shortcircuit with the adjacent electrode needle generated when electrode needles are arranged at high density. The firsts and second supports 101, 102 and the electrode needles 103 are fixed by filling the spaces formed by all of them with a resin 104. By this method, an electrode head having high resolving power can be inexpensively manufactured and high reliability can be realized and an excellent recording apparatus can be provided.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a writing electrode head for a recording device that records electrical signals as visible images.

BACKGROUND OF THE INVENTION Among various recording apparatuses, recording apparatuses that conduct electricity through electrode needles, such as discharge recording apparatuses, electrolytic recording apparatuses, and energization recording apparatuses, are superior in terms of high speed, record storage stability, and economical efficiency. However, the print quality of these devices was not very good.

That is, the resolution was not very good, typically 5 to 6 dots/mm.

Problems to be Solved by the Invention Regarding the above-mentioned recording device, for example, a discharge recording device, the resolution of the discharge phenomenon itself is higher, and the recording speed is also lower than that of a paper-width multi-stylus (multi-electrode head).
Even though it would be possible to write for one second per A4 sheet if there were, the reason why the performance is kept low is due to the writing electrode head. The tip of the electrode head (the part that comes into contact with the recording paper) becomes extremely hot, so the electrode needle was forced to protrude. Furthermore, because of this, high-density (high-resolution) electrode heads use thin electrode needles, which pose a problem of bending. An embedded type electrode head without protruding electrode needles was considered, but this was not possible due to the lack of a good material that could withstand high temperatures and the lack of a method for embedding the electrode needles in a dense array.

Problems related to such high-density electrode heads are not limited to discharge breakdown recording devices (they are also common to other recording devices, such as electrolytic recording devices and energization recording devices that conduct electricity through electrode needles). Met.

Means for Solving the Problems In order to solve the above problems, the present invention has an electrode head structure in which a plurality of grooves are formed on the surface of an electrically insulating first support, and an electrode needle is placed in each groove. An electrically insulating second support is provided thereon, and a space formed by the first and second supports and the electrode needles is filled with resin.

Operation The present invention realizes a higher-resolution, cheaper, and more reliable electrode rad with the above-described configuration.

Example The present invention will be described below with reference to the drawings.

FIG. 1 shows a perspective view of an embodiment of the electrode head of the present invention. In Fig. 1, 101 is an electrically insulating first
102 is an electrically insulating second support. Grooves are formed on the surface of the electrically insulating first support. The material of the support should not only be electrically insulating but also soft enough not to damage the surface of the recording paper since it runs in contact with the recording paper. For example, a sintered body of 60,000-crystalline boron nitride or gypsum may be used. In addition, in the case of a composite with a resin or the like, it is preferable to use 60,000 boron nitride, calcium carbonate, talc, etc. as a filler. The material of the support body 102 is the same. The electrode needle 103 is a commonly used conducting wire having a circular or square cross section. Copper wire is the easiest to handle. Among these, coated copper wires (often called enamelled wires) are preferable in order to prevent short circuits with adjacent electrode needles when electrode needles are arranged in a high density manner. Tungsten wire, nickel wire, or stainless steel wire may also be used. However, nickel wire is expensive, and other wires have problems that must be overcome in making electrode heads, such as difficulty in connecting them to electrical circuits. 104 is the first support 101 and the second support 1
This is a resin that fills the space created by 02 and electrode needle 103 and fixes each of them. Otherwise, if the resin does not fill the space, for example, in Figure 1, apply the resin only to the lower part that does not belong to the record, or apply the resin only to the peaks of the grooves of the support. Not only does the mechanical strength become weaker, but the space becomes clogged with dirt and print quality deteriorates.

Example 1 A sintered body of boron nitride in the form of a plate (length 20 mm x width 20 mm x thickness 20 mm) was prepared as a first support.

On this surface, 128 grooves with a width of 40 μm, a depth of 40 μm, and a pitch of 63 μm (16 grooves/dragon) were cut using a dicing saw for processing semiconductor wafers. A copper wire with a diameter of 30 μm was wound around the groove of this sintered body of hexagonal crystal boron nitride using a winding machine, and a commercially available room temperature curing epoxy resin (Araldite manufactured by Ciba Corporation) was applied thereon. Next, a plate-shaped (length 20n) was used as the second support.
A sintered body of 60,000-crystalline boron nitride (width x 20 weights x 1 mm thick) was stacked on top of the epoxy resin and left at room temperature to harden the resin. The tip was ground so that it would come into contact with the recording paper, and each of the coated copper wires that came out on the other side was connected to the drive circuit shown in FIG. 2. FIG. 2 shows only the output portion of one of the 128 circuits. 201 is an NPN) transistor, the emitter is connected to the negative power supply (-45V),
The base was connected to a signal source. 202 is a protection resistor.

203 is a capacitor. In the experiment, each was 100Ω.
, 0.01 μF was used. Point 204 was extended and connected to the covered copper wire. Then, when the tip of this electrode head was pressed against the discharge recording paper and the surface of the recording paper was connected to the ground and moved at 3 cm/sec, characters of 16 doso/liter could be printed finely.

In Example 1, a coated copper wire was used as the wire, but it is clear that a bare copper wire or other conductive wire may be used. However, in that case, measures must be taken to prevent the parallel wires from coming into contact with each other. It is clear that the cross section of the wire can be of any shape, but a circular shape is common and inexpensive. Furthermore, in the first embodiment, the present invention has been explained by adopting a wire winding method as the manufacturing method of the electrode head, but there is no necessity to stick to this method at all.

Example 2 An electrode head was fabricated in Example 1 by replacing the resin with an acrylic instant adhesive (trademark: Aron Alpha). When the same experiment as in Example 1 was conducted, similar results were obtained.

Example 3 Assembled in Example 1 without applying resin, tightened and fixed with a vise used in machining, poured Aron Alpha used in Example 2 through the gap between the support and the electrical conductor, and hardened it to form the electrode head. Had made. Using this electrode head, the same experiment as in Example 1 was conducted, and the same results were obtained.

Example 4 A plate-shaped material (length 20 x width 20 x 2 x thickness) made of a composite material made by mixing and curing 90% by weight of 60,000-crystalline boron nitride powder and epoxy resin (bisphenol A type resin). A first support was prepared. A similar second support was also prepared. Groove processing similar to that in Example 1 is applied to the first support,
Assembled similarly.

゛When the same experiment as in Example 1 was conducted, good printing was obtained.

Example 5 A first support in the form of a plate (length 20fi x width 20n x thickness 2mm) made of a composite obtained by mixing and curing 80% by weight of talc powder and epoxy resin (bisphenol A type resin) was prepared. did. A similar second support was also prepared. This time, we made grooves 60μ wide, 60μ deep, and 125μ pitch. A 50μ bare copper wire was used as an electrode needle.

When assembled in the same way and conducted a similar experiment, the diameter of the dots increased, but printing with gaps between the dots was obtained. Therefore, the printing quality was somewhat inferior to that of Examples 1.2.

Effects of the Invention As is clear from the above explanation, in order to solve the above problems, the present invention has an electrode head structure in which a plurality of grooves are formed on the surface of an electrically insulating first support, and each groove is filled with a plurality of grooves. Electrode needles are provided, covered with an electrically insulating second support, and the space created by the first and second supports and the electrode needles is filled with resin. As a result, a high-resolution electrode head can be manufactured at low cost, high reliability can be achieved, and an excellent recording device can be provided.

[Brief explanation of drawings]

FIG. 1 is a block diagram of the electrode head of the present invention, and FIG. 2 is a circuit diagram of a drive circuit used in the experiment. 101... Electrically insulating first support, 102
...Electrically insulating second support, 103...
...Electrode needle, 104...Resin, 201...
...Transistor, 202...Protection resistor, 2
04... Capacitor. Name of agent: Patent attorney Toshio Nakao Haka1 person t03--
-Electric St body IO2----'lN 1st diagram 2nd diagram

Claims (4)

[Claims] (1) An electrode head used in a recording device that records images using an electric needle, in which a plurality of grooves are formed on the surface of an electrically insulating first support, and an electrode needle is inserted into each of the grooves. The electrode head is provided with an electrically insulating second support covering the electrode needle, and a space formed by the first and second supports and the electrode needle is filled with resin. . (2) The electrode head according to claim 1, wherein the first support and the second support are made of a sintered body of hexagonal boron nitride. (3) Claims 1 to 2, characterized in that the first support and the second support are composites made of hexagonal boron nitride powder and thermosetting resin. The electrode head according to any of the above. (4) The electrode head according to claim 1, wherein the electrode needle is a covered conductor.