JPS5935231B2 - writing recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a recording method in which a large number of mutually insulated recording electrodes are arranged on a burnable metal layer of a record carrier, and the recording electrodes are moved under the recording electrodes by an applied voltage. The present invention relates to a writing/recording device that burns and destroys the surface portion of a metal layer of a carrier.

The apparatus of the present invention uses so-called recording metal paper as a record carrier.

This recording metal paper is a paper in which a black lacquer layer is first applied as a contrast layer, and an aluminum layer is applied thereon as a recording layer. When a current is passed through the electrode, the metal layer, preferably the aluminum layer, is substantially evaporated under the electrode by Joule heating, and a contrast-rich lacquer layer appears as a recording trace. As the metal layer, for example, a mixed layer of zinc and cadmium can be used instead of aluminum. Recording metal paper refers to the entire structure of base paper, contrast layer of lacquer, and metal layer that can be destroyed by firing.

The structure of this type of recording metal paper is basically known.
"Burn destruction" essentially means, as already explained, the evaporation of the metal layer under the electrode by Joule heat.

At this time, the lower part of the metal layer of the electrode disappears and adheres to other parts around the burned-out part. In some areas, an arc also forms under the electrode, and the metal layer is oxidized, resulting in metal oxides and hydroxides as well. Some of these metal oxides and hydroxides adhere to the recording metal paper and some to the electrodes around the burned-out area. In the case of devices of the type mentioned at the beginning, the record carrier (RMP-
The recording electrode (band) always moves in the same direction, as a result of which the fixed recording electrode causes worn metal particles of the metal layer to adhere to the tip of the recording electrode, forming burnout residues and oxide whiskers.

These oxidized whiskers (electrification properties) can lead to short-circuits in recording electrodes arranged in parallel with a small distance, such as character decoding recorders and perforation recorders. In this case, the metal layer of the record carrier is destroyed in an unfavorable manner under both recording electrodes which are shorted to each other. An object of the present invention is to render short-circuit bridges between recording electrodes harmless in a simple manner.

According to the present invention, this problem is solved as follows.
That is, during recording, a burn-out voltage is applied to the recording electrodes via a switching device, and at the same time, during the recording operation of some recording electrodes that are recording, other recording electrodes that are not recording are switched on. It was designed to be directly grounded.

The present invention will be explained in detail below using examples shown in the drawings.

FIG. 1 shows a recording head 20 for character and symbol decoding recording having a large number of recording electrodes 21 arranged in parallel.

These recording electrodes are mutually insulated by a thin mica layer. A band 22 made of recording metal paper moves in the direction of the arrow below the recording electrode 21, and the metal layer is grounded via a wide electrode 23. The entire structure of this recording metal paper has already been described. The strip 22 then runs over rollers 24, which press it with the necessary pressure against the ends of the earth electrode and the recording electrode. During recording, at least a portion of the recording electrodes are not supplied with recording signals. In order to eliminate short-circuit bridge disturbances occurring between the recording electrodes 21 due to the adhesion of chargeable residues, the non-recording electrodes are grounded by an electronic switching device 25.
That is, all non-recording electrodes that are part of the total recording electrodes are grounded, and the recording pulses of each adjacent electrode burn out the shorted bridge. There is no need for a forced shutdown in order to remove the shorted bridge by burning out. A burnout voltage is applied to the recording electrode 21 via the switching device 25 during recording, and during the recording operation of some of the electrodes that are recording during the recording,
The other electrodes that were not recording were directly grounded.

If a shorting bridge 28 is formed between two adjacent recording electrodes 21, when a negative burn-out pulse is applied to one of both recording electrodes 21, current flows to the adjacent recording electrode that does not record. The subsequent short-circuit current flowing to ground via the switching device 25 causes the short-circuit bridge 28 to burn out without sustaining an arc between the two recording electrodes 21. In order to prevent the recording electrode 21 from short-circuiting due to dust adhesion or small metal pieces with a relatively large cross-section, the end surface of the recording electrode 21 is coated with an insulating layer 27 made of mica.
Only the narrow tip portion of the electrode end face is not coated. The burn-out voltage for short circuit bridge removal is generally a DC voltage applied to each electrode as a recording voltage.

This voltage is typically a negative DC voltage, for example about 20-50 volts. Instead of a negative voltage, a positive voltage can also be used, but applying a negative recording voltage will result in a comparative A favorable situation can be obtained. Basically, a negative voltage or a positive voltage may be used as the recording voltage or the burning breakdown voltage. The recording voltage for the recording electrode is therefore at least partially applied to the short-circuit bridge and the adjacent electrode connected to earth, and at the same time serves as the breakdown voltage of the short-circuit bridge. That is, one voltage serves both as the burning breakdown voltage for recording and as the voltage for removing short-circuit bridges. Next, the specific operation of the switching device will be explained.

The switching device 25, which connects the non-recording electrode to ground, is schematically illustrated in FIG. 1 as an electromechanical switching device. In practice, the device is preferably constructed as an electronic switching device using transistors. As can be seen from FIG. 1, some of the recording electrodes that are not recording out of all the recording electrodes are all connected together and simultaneously to ground by the switching device, in which case this connection is of course This can be done via a common electronic switch or via individual electronic switches. Incidentally, it is clear to the person skilled in the art that the circuit can be designed such that the current flowing through the short-circuit bridge is no greater than the current required for burnout removal.

The magnitude of this current depends on the arrangement of the electrodes and other devices and can be easily determined by experimentation with each arrangement.

[Brief explanation of the drawing]

Figure 1 shows a character with recording electrodes connected to a switching device.
Figure 3 shows a perspective view of the recording head of the symbol decoder and recorder. 20... Recording head, 21... Recording electrode, 22... Band, 23... Earth electrode, 25... Switching device, 28・・・・・・Conductive bridge.

Claims (1)

[Claims] 1 A number of mutually insulated recording electrodes are arranged on a burnable metal layer of a record carrier, and the recording electrodes burn the surface portion of the metal layer of the record carrier moving under the recording electrodes by an applied voltage. In a write-recording device that is subject to destruction, a burnout voltage is applied to the recording electrode 21 via a switching device 25 during recording, and the recording operation is simultaneously performed by some of the recording electrodes that are recording at the time of recording. A writing/recording device characterized in that other recording electrodes that are not grounded are directly grounded.