JPS59209153A - Apparatus for recording magnetic flowable substance - Google Patents

Abstract

PURPOSE:To obtain a recording image having high resolving power and high quality, by providing a magnet for protruding a flowable toner at the leading end of a single tapered magnetic metal needle or each of a plurality of tapered magnetic metal needles provided in corresponding relation to a recording surface. CONSTITUTION:When magnetic flowable toner 4 is distributed on a magnetic metal needle 10, it is held in the vicinity 11b of the leading end of the magnetic metal needle 10 in a slightly large amount. If the magnetic field in the vicinity 11b of the leading end of the magnetic needle 10 is intensive as shown by this phenomenon, the stream of the flowing magnetic flowable toner 4 becomes fast and the supply capacity of the magnetic flowable toner 4 to the leading end 11a of the magnetic metal needle 10 is enhanced because the amount of the magnetic flowable toner 4 held in the vicinity 11b of the leading end of the magnetic metal needle 10 is much. Therefore, the magnetic flowable toner 4 flies toward a recording surface from the leading end 11a of the magnetic metal needle 10 and rapidly supplied even if the magnetic flowable toner 4 held by the leading end 11a of the magnetic metal needle 10 is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention holds and bulges magnetic fluid toner by magnetic force on a single or plural magnetic metal needles, and applies a Coulomb force to the bulged magnetic fluid toner to make the magnetic fluid toner magnetic. This relates to a magnetic fluid recording device that prints on the recording surface by flying fluid toner.By increasing the magnetic force near the tip of the magnetic metal needle and forming a slightly strong magnetic field, it Improves the supply of magnetic fluid toner,
The present invention aims to provide a magnetic fluid recording device that can obtain high resolution, high quality recorded images, and high speed recording.

The magnetic metal needle of conventional magnetorheological recording devices has high resolution,
In order to obtain high-quality recorded images, thin magnetic wires obtained by drawing with good dimensional accuracy and easy production are cut to a certain size and used singly or in multiple lines. An example of a conventional device is shown in FIGS. 1 and 2.

FIG. 1 is a front view of the main part, showing the state in which the magnetic fluid toner is held. FIG. 2 is a right side view of FIG. 1, showing the output of magnetic lines of force and the state of retention of the magnetic fluid toner. A plurality of magnetic metal needles 1 are arranged on a substrate 2 at equal intervals. A protrusion magnet 3 for magnetizing the magnetic metal needle 1 is adhered to the magnetic metal needle 1 at a distance A behind the magnetic metal needle tip 1a. The particles forming the magnetic metal needle 1 are arranged in the drawing direction (direction B), the so-called axial direction (hereinafter referred to as axial direction B), because the magnetic wire material obtained by drawing processing is used. Therefore, when the magnetic metal needle 1 is magnetized, it tends to be strongly magnetized in the axial direction B. Also, when a magnetic material is magnetized,
Corners of magnetic materials tend to generate stronger magnetic force than smooth surfaces. Therefore, when the magnetic metal needle 1 was magnetized by the bump magnet 3, a strong magnetic force was generated at the tip 1avCid of the magnetic metal needle, and a strong magnetic field was formed, as shown by the lines of magnetic force (arrow lines) C in FIG. However, since the portion 1b near the tip of the magnetic metal needle is strongly magnetized in the axial direction B, there is little magnetic force leaking from the outer peripheral surface of the magnetic metal needle 1, and the outer peripheral surface of the magnetic metal needle 1 is a smooth surface. Because of this, there was no place to generate strong magnetic force, and only a weak magnetic field was formed. When magnetic fluid toner is externally supplied onto the magnetic metal needle 1 and the bump magnet 3 that have been magnetized in this way, the magnetic fluid toner will respond to the strength of the magnetic field as shown in FIGS. 1 and 2. A magnetic fluid toner 4 is disposed on the magnetic metal needle tip 1a and the bump magnet 3 in a large amount, and a large amount is applied 171 on the magnetic metal needle tip vicinity portion 1b.
j. A small amount of magnetic fluid toner 4 is retained. Further, the magnetic fluid toner 4Fi held by the magnetic metal needle tip 1a,
A protuberance 5 is formed to cover the magnetic metal needle tip 1a.

The size of the tip radius R of the bulge 5 shape is the size of the magnetic metal needle tip 1.
The stronger the magnetic field a, the stronger the intensity, and the greater the amount of externally supplied magnetic fluid toner.

Reference numeral 6 denotes a control electrode, which is provided facing and spaced apart from the magnetic metal needle 1. Reference numeral 7 denotes recording paper, and the surface of the recording paper facing the magnetic metal needle 1 is in contact with the control electrode 6. 8 is a control circuit that causes the magnetic fluid toner 4 to fly onto the recording medium 7.

A control circuit 8 [Thus, when electricity and pressure are applied between the magnetic metal needle 1 and the control electrode 6, a Coulomb force acts on the tip of the protuberance 6,
The magnetic fluid toner 4 flies toward the recording medium 7, and a print is obtained on the recording medium T. The smaller the radius R of the tip of the protuberance 5, the lower the applied voltage required to make the magnetic fluid toner fly. Just like that, flying magnetic fluid toner 4
The amount of N increases as the radius R of the tip of the protuberance 5 increases, and as the amount of flying magnetic fluid toner 4a increases, a recorded image with a higher print density can be obtained.

When the magnetic fluid toner 4a flies toward the recording medium 7, the amount of the magnetic fluid toner 4 that can be held at the magnetic metal needle tip 1aK decreases, and the tip radius R of the bump 5 becomes small σ.
Due to the magnetic force, the magnetic fluid toner 4 on the bumping magnet 3 is supplied through the magnetic metal needle tip vicinity portion 1b.

However, as mentioned above, the magnetic field near the tip of the magnetic metal needle 1b is weak due to the small leakage magnetic force from the outer peripheral surface.
Therefore, the flow of the magnetic fluid toner 4 flowing through the magnetic metal needle tip vicinity portion 1b is slow, and the amount of magnetic fluid toner 4 held by the magnetic metal needle tip vicinity portion 1b is small, and the magnetic fluid toner 4 flows through the magnetic metal needle tip vicinity portion 1b. The supply ability of the magnetic fluid toner 4 was low. In order to always obtain a recorded image with uniform print density, it is necessary to keep the amount of flying magnetic fluid toner 4a constant at all times, and for this purpose, it is necessary that the radius R of the tip of the bulge 5 when flying is constant. It is.

Therefore, if the amount of magnetic fluid toner 4 held by the magnetic metal needle tip 1a always reaches a certain amount at the start of flight,
A recorded image with uniform print density is always obtained.

However, as described above, in the conventional configuration, the ability to supply the magnetic fluid toner 4 to the magnetic metal needle tip 1a in the vicinity of the magnetic metal needle tip 1bvC was low, so that a recorded image with uniform print density could not be obtained. When I tried to record it, I couldn't record it at high speed. Furthermore, when high-speed recording was performed, only recorded images were obtained in which the print density decreased as the recording progressed. Unfortunately, due to the difference in information density, the amount of magnetic fluid toner 4 held by the magnetic metal needle tip 1a at the start of flight changes, so the amount of flying magnetic fluid toner 4a increases or decreases, causing printing on the recorded image. There was uneven density. In addition, in order to increase the supply capacity in the vicinity of the magnetic metal needle tip 1b, the bumping magnet 3 is provided close to the magnetic metal needle tip 1a, so that the magnetic fluid toner 4 flows through the magnetic metal side tip vicinity 1b. When the supply capacity was improved by shortening the distance, the supply performance of the magnetic fluid toner was improved, but the magnetic field of the magnetic metal needle tip 1a became stronger, and the magnetism held by the magnetic metal needle tip 1a became stronger. Since the amount of fluid toner 4 increased, the amount of flying magnetic fluid toner 42L increased, and the resolution of the recorded image became extremely poor.

The present invention solves the above-mentioned conventional drawbacks, and will be explained below based on drawings showing an embodiment of the present invention. ○ Figures 3 to 5 are side views of essential parts showing an embodiment of the present invention. be. FIG. 6 shows how magnetic lines of force emerge and how magnetic fluid toner is held in an embodiment of the present invention. 10 is a magnetic metal needle provided on the substrate 2. On the magnetic metal needle 10, a protruding magnet 3 for magnetizing the magnetic metal side 10 is adhered at a distance A behind the magnetic metal needle tip 11a. 112L indicates a portion near the tip of the magnetic metal needle, and a portion ILb [gradient surface] near the tip of the magnetic metal needle.

The magnetic metal needle 10 is formed into a tapered shape by providing a tapered surface or the like.

As an example of forming the magnetic metal needle 1o into a tapered shape, at least one sloped surface is provided as shown in FIG. As another embodiment, it is formed into a substantially conical or substantially truncated conical shape, as shown in FIG. The bent magnetic metal needle tip 11b'' is tapered stepwise as shown in FIG. A leakage magnetic force is generated on the end face 110 of the nine stages of the outer circumferential surface of the approximately truncated conical shape, and the magnetic metal needle near the tip 11
A somewhat strong magnetic field is formed at points b, etc. (C is a line of magnetic force).

Therefore, when the magnetic fluid toner 4 is placed on the magnetic metal needle 1o, as shown in FIG.
A slightly larger amount of magnetic fluid toner 4 is held in 1b.

In this way, when the magnetic field near the tip of the magnetic metal needle 11b is strong, the portion near the tip of the magnetic metal needle 11 is
Since the flow of the magnetic fluid toner 4 flowing along the magnetic metal needle tip 11b is fast, and the amount of the magnetic fluid toner 4 held by the magnetic metal needle tip vicinity portion 11b is large, the magnetic fluid toner 4 flows to the magnetic metal needle tip 11a. The supply ability is improved, and the magnetic fluid toner 4a is distributed from the magnetic metal needle tip 112L toward the recording surface.
Even if the magnetic fluid toner 4 held by the magnetic metal needle tip 112L decreases due to flying, the magnetic metal needle tip 11& is quickly replenished with the magnetic fluid toner 4, and the density of the recorded image does not change.

As described above, according to the present invention, a gradient surface is formed in the vicinity of the tip of the magnetic metal needle, or the vicinity of the tip of the magnetic metal needle is formed into a substantially conical or truncated conical shape, or a step is formed in the vicinity of the tip of the magnetic metal needle. By forming the magnetic metal needle into a tapered shape,
The magnetic field near the tip of the magnetic metal needle is formed to be slightly stronger, and the ability to supply the magnetic fluid toner to the tip of the magnetic metal needle is improved. Therefore, the amount of magnetic fluid toner retained by the tip of the magnetic metal needle can be maintained at a nearly constant amount, and the amount of flying magnetic fluid toner can also be maintained at a nearly constant amount, regardless of the information density even during high-speed recording. , it is possible to always record with a substantially constant print density, and a recorded image with good print quality can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a front view of the main parts of a conventional magnetic fluid recording device.
Figure 2 is a right side view, Figures 3 and 4. FIG. 5 is a side view of a main part showing an embodiment of the present invention, and FIG. 6 is a side view showing how magnetic lines of force emerge and the state of holding magnetic fluid toner in an embodiment of the present invention. 10---Magnetic metal needle, 11&, 11a', 11a''・
...Magnetic metal needle tip, 11b, 11b', 11b''-
... Near the tip of the magnetic metal needle. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
Factor Figure 3 Δ Factor 4 Figure 5 Δ

Claims (1)

[Claims] a single or plural magnetic metal needles provided corresponding to the recording surface; a bumping magnet for raising magnetic fluid toner at the tip of the magnetic metal needle; and a bumping magnet for magnetic fluid toner raised at the tip of the magnetic metal needle. 1. A magnetic fluid recording device, comprising: a control means for causing a magnetic metal needle to fly or migrate to a recording surface in response to an image signal, and wherein the magnetic metal needle has a tapered shape.