JPS5838171A - Magnetic ink recorder - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention The method of the present invention relates to a magnetic ink recording device, which improves selectivity by reducing the meniscus radius at the tip of a needle electrode that attempts to fly magnetic ink using an electrical signal, thereby reducing recording noise. The purpose is to eliminate this problem and lower the recording voltage.

FIG. 1 is a matrix configuration diagram of a recording head of a conventional magnetic ink device.

As shown in FIG. 1, every other needle electrode 1 is electrically short-circuited (the number forming the matrix is arbitrary). Connected to circuit 3. On the other hand, the same selection signal as the selection signal applied to the needle electrode 1 is applied to the counter electrode 2 according to the image signal applied to the needle electrode 1 facing the counter electrode 1 by the counter electrode control circuit 6 and the counter electrode high voltage switching circuit 4. A voltage pulse is applied at the appropriate timing.

FIG. 2 shows a schematic diagram of the recording section of the recording apparatus. Ink chamber 1
The same static pressure is always applied to the magnetic ink 11 contained in the magnetic ink 2 by a means for keeping the liquid level constant. The magnetic ink 11 supplied to the raised magnet 8 by the slit magnet 9 for supplying magnetic ink is affected by the magnetic retention force of the tip of the needle electrode 1 magnetized by the raised magnet 8, the surface tension of the magnetic ink 11, and the magnetism. A meniscus is formed at the tip of the needle electrode 1 due to the balance with the gravity acting on the ink 11. On the other hand, a counter electrode 2 is provided opposite the needle electrode 1 with a recording paper 13 in between.

The control circuit 6 shown in FIG. 1 sequentially sends selection signals a t b t c + d + e + f as shown in FIG.
+ ... @ Needle electrodes 1 a , 1 b , 1 c in which J constituted a matrix.

1d, fe, 1f yen...Added to 11. On the other hand, voltage pulses controlled by control signals from the counter electrode control circuit 6 indicated by A and B in FIG. 3 are applied to the counter electrodes 2a, 2b, etc. Furthermore, between the needle electrode 1 and the counter electrode 2,
A bias voltage is always applied by the bias power supply. FIG. 4 is a diagram schematically showing the tip meniscus shape of the needle electrode 1 immediately after a recording signal is applied. Needle electrode 1
When a voltage pulse is applied to the needle electrode 1, charges 14 appear on the meniscus surface due to charge injection from the needle electrode 1 or polarization.

At this time, when a voltage pulse corresponding to the image signal is simultaneously applied to the counter electrode 2, the charge 14 is attracted to the electric field created between this charge 14 and the counter electrode 2, as shown in FIG. , the tip of the meniscus is pulled toward the counter electrode 2, and as a result, the radius of curvature of the meniscus becomes smaller.As shown in FIG. fly upwards. The element that determines the flight of this magnetic ink is the initial meniscus shape, and the smaller the radius of curvature of the meniscus, the lower the voltage and the shorter the response time that the magnetic ink starts flying. However, due to the precision of the arrangement interval of the needle electrodes 1, the precision of the magnetic field line distribution of the bump magnet 8, etc., even in the same recording head, not all menisci are always the same. This means that if a voltage pulse is applied to the counter electrode 2 from the needle electrode 1 to which no selection signal is applied, the magnetic ink 11 will fly toward the counter electrode 2 only by this voltage pulse and the electric field from the bias power supply 7. It shows that it is possible. In other words, since there is no distinction in the initial state between the needle electrode 1 for recording and the needle electrode for non-recording, noise is generated and the printed image is spoiled.

The present invention aims to eliminate such drawbacks and to provide a magnetic ink recording device that can obtain recorded images with less noise.

An embodiment of the present invention will be described below with reference to FIGS. 7 to 10. FIG. 7 is a block diagram showing a matrix configuration of a recording head section of a magnetic ink recording apparatus according to an embodiment of the present invention, FIG. 8 is a timing chart diagram of the same, FIG.
FIG. 10 is an explanatory diagram of the same operation. The matrix configuration shown in FIG. 7 includes the needle electrode control circuit 16. Counter electrode control circuit 16
The needle electrodes 1, which are the same as those in FIG. It is connected to the high voltage switching circuit 3.

On the other hand, the counter electrode 2 receives a voltage pulse at the same timing as the selection signal to be recorded by the counter electrode 1 by the counter electrode high voltage switching circuit 4 according to the image of the needle electrode 1 facing the counter electrode 1 by the counter electrode control circuit 16. is applied.

FIG. 8 shows l, m in the needle electrode selection signals by this device.

A timing chart of n, O, p, . . . t and the counter electrode control signals RI and E is shown. Needle electrode selection signal k.

1, m, fl, Q, p,...1
1. Each has a pulse signal with a wide time width for performing the original recording, and a pulse signal with a narrower time width before and after it.

1. The needle electrode selection signal shown in FIG. m, n.

' + p...t is the needle electrode high voltage switching circuit.

3b, 3a, 3d, 3e, 3f... are added to 3j, respectively.

Figure 9 shows needle electrode 1C when recording an image with needle electrode 1c.
Shows the state of the tip.

A wide voltage pulse is applied to the needle electrode 1c from a needle electrode high voltage switching circuit 3C controlled by a needle electrode selection signal m. At this time, at the same time, the needle electrodes 1b, 1
d also has needle electrode selection signal 1. Needle electrode high voltage switching circuit 3b controlled by n.

3d, a voltage pulse with a narrow time width is applied.

Then, charges 14 appear in the magnetic ink 11 at the tips of the needle electrodes 1b, 1c, and 1d due to polarization or charge injection. Since this electric charge 14 has the same polarity, the electric charges of needle electrodes 1b and 1c, 1d and 10 repel each other as shown by the arrows in FIG. 9, and as a result, as shown in FIG. 10. In this manner, the radius of curvature of the meniscus at the tip of the needle electrode 1c becomes small, creating a condition in which the magnetic ink 11 is extremely easy to fly.

As described above, according to the present invention, in addition to the original selection signal, pulses with a narrow time width are added before and after the needle electrode control signal.
By electrically reducing the radius of curvature of the meniscus formed at the tip of the needle electrode, it becomes possible to improve the selectivity of the needle electrode and obtain high-quality recorded images with less noise.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the matrix configuration of the recording section of a conventional magnetic ink recording device, Fig. 2 is a perspective view schematically showing the recording section of the same magnetic ink recording device, and Fig. 3 is a needle electrode selection in the same device. FIG. 4 is a timing chart diagram of signals and counter electrode control signals. 5 and 6 are explanatory diagrams of the operation of the leading end of the recording section of the same apparatus, FIG. 7 is a block diagram showing the matrix configuration of the recording section of a magnetic ink recording apparatus according to an embodiment of the present invention, and FIG. Timing charts of the needle electrode selection signal and counter electrode control signal in the same apparatus, and FIGS. 9 and 10 are explanatory diagrams of the operation of the recording section tip of the same apparatus. 1...Needle electrode, 2...Counter electrode, 3.
...Needle electrode high voltage switching circuit, 4...
・Counter electrode high voltage switching circuit, 5... Counter electrode control circuit, 6... Needle electrode control circuit, 7...
...Bias power supply, 8...Elevation magnet, 9.
...Supply slit magnet, 1o...Base,
11... Magnetic ink, 12... Ink chamber,
13...Recording paper, 14...Electric charge, 15.
...Needle electrode control circuit, 16...Counter electrode control circuit.

Claims (1)

Scope of Claims: (1) A plurality of needle electrodes each having magnetic ink held at their tips and a plurality of opposing electrodes are provided using magnetic force, and a selection signal is applied to the needle electrodes and an image is applied to the opposing electrodes. configured to apply a signal and cause magnetic ink to fly from the needle electrode onto a recording paper disposed near the counter electrode to form an image;
A magnetic ink recording device characterized in that a recording signal is applied to a needle electrode for causing magnetic ink to fly according to an image, and at the same time, a signal is also applied to one or both needle electrodes adjacent to the needle electrode. (2. In the statement of claim 1, the signal to be applied to one or both needle electrodes adjacent to the needle electrode to be recorded at the same time has a narrower time width than the selection signal. A magnetic ink recording device characterized by: (3) In the description of claim 1, the signal applied to one or both needle electrodes adjacent to the needle electrode at the same time as the needle electrode to be recorded is set to have a waveform higher than the selection signal. A magnetic ink recording device characterized by having a low high value.