JPS6016633B2 - magnetic display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention has a permanent memory retention function without power consumption,
The present invention also relates to a rewritable magnetization reversal type magnetic display device.

An example of a conventional magnetic display device is “A Magn
etic 1 Parecles Display
lEEETransactions on Elec
tron DEvices, Vol. ED-Matsu, No.
9, September975. It has been known.

According to this paper, half of a spherical magnetic particle with a diameter of about 10 mm is painted black and white and magnetized, and this single magnetic particle is formed into a flat plate with a diameter of 15 mm and a wall thickness of 2 mm. 5〆m
The magnetic particles are sealed together with a liquid in a container, and a magnetic display device is formed by rotating the magnetic particles using a magnetic field from a drive unit placed on the back side. However, with this method, it is not easy to make magnetic particles with a diameter of about 10 rudders into a truly spherical shape with uniformity, and there are problems with actual manufacturing, such as defects in the matrix, the size of the display, and the assembly of the driving board. It seems that there are many problems. The purpose of the present invention is to eliminate these drawbacks by forming a colloidal liquid in which magnetic fine particles with a diameter of 100 to 150 angstroms are stably and uniformly dispersed at a high concentration into a flat plate. Each formed element is filled and sealed, and the magnetization of a portion of a plurality of magnets arranged for each element is reversed from the outside by a coil, thereby functioning as a display device, which will be described in detail below. do.

FIG. 1 is a diagram illustrating the principle of one element of a magnetic display device explaining a first embodiment of the present invention.

FIG. 1a is a top perspective view in a state where no display is made, and FIG. 1b is a sectional view taken along the line A--A in FIG. 1a. 1 is usually black magnetic fine particles.

2 is a water or hydrocarbon liquid containing magnetic fine particles 1 at a high concentration.

The liquid 2 may be colored white or another color, or may be transparent. 3 is a container that can transmit light.

4 and 5 are magnets, and 6 is a coil attached to the magnet 5.

Numerals 7 and 8 are shielding plates arranged opposite to the magnets 4 and 5 to make the magnetic fine particles 1 invisible when viewed from the direction of the arrow 9.

As shown in FIG. 1b, when the magnetization direction of the magnet 4 and the magnetization direction of the magnet 5 by the coil 6 are set in the same direction, the magnetic fine particles 1 are concentrated around the magnets 4 and 5, and are concentrated on the back surfaces of the shielding plates 7 and 8. Since it is stationary, when viewed from the direction of arrow 9, the colored liquid 2 can be seen through the container 3, and if the liquid 2 is transparent, the hair wall 10 of the container 3 can be seen.

FIG. 1c is an explanatory diagram in which the arrangement of the coil 6 in FIG. 1b is changed, and the coil 12 formed on the insulating plate 11 is attached to the surface of the magnet 5, and is particularly suitable for miniaturized displays. This is an effective winding mounting configuration in the device.
FIG. 1d is an explanatory diagram of erasing the display using a permanent magnet, and by moving the permanent magnet 14 in the direction of the arrow 13, the cover magnetic direction of the magnets 4 and 5 becomes the same direction as in FIG. 1b. In other words, it can be brought into a state where it is not displayed as a magnetic display device.

FIG. 1e is a top perspective view of the displayed state, and FIG. 1f is a sectional view taken along the line B--B in FIG. 1e.

When the coil 6 is energized and the magnetization direction of the magnet 5 is reversed,
Due to the mutual magnetic force between the magnets 4 and 5, the magnetic fine particles 1 move in the liquid 2 so as to connect the magnets 4 and 5. Therefore, when viewed from the direction of arrow 9, black magnetic particles 1 can be seen through container 3, and it can be seen that characters and figures can be written by reversing the magnetization of the magnet by coil 6. In this case, it is necessary that the magnet 4 is not affected by the magnetization by the coil 6. In addition, in the explanation of the entrustment, the coil 6 is made up of one piece and the magnetization is reversed by changing the current direction, but the coil 6 can be made up of two pieces and each coil can be used for writing and erasing. . An example in which the single element described above is configured as an aggregate will be described with reference to FIG. 2.

FIG. 2a shows an example of displaying magnetic characters and figures by magnetization reversal, and FIG. 2b is a sectional view taken along the line C--C in FIG. 2a.
A grid-like convex portion 16 is formed on the container 15 integrated into a flat plate shape to constitute each element unit, and the liquid 1
7 and magnetic fine particles 18 are enclosed. Here magnets 19, 20
The coil 21 is attached to the magnet 20'. In such a configuration, the coil 21 is first passed through the coil 21, the magnetization direction of the magnet 20 is made the same as that of the magnet 19, and then the coil 21 is
By selectively energizing or not energizing, a magnetic display can be operated by magnetization reversal.

In addition, as shown in FIG. 1d, by the movement of the permanent magnet 14,
By making the magnetization direction of the magnet 20 the same as that of the magnet 19 and then selectively energizing or not energizing the coil 21, it is possible to operate as a magnetic display. Note that 22 is a shielding plate. As described above, in the first embodiment, writing and erasing of the display device is possible by reversing the magnetization of the magnet by the coil, and rewriting is also easy.

Further, since each display element has a magnet and a coil, it is easy to partially rewrite the data after writing is completed as a device. Furthermore, since the display uses magnets, it has a permanent memory function and can retain the display even when no electricity is applied. It has many advantages in terms of price, such as being low in price because it uses general-purpose materials, and being highly stable against changes over time. FIG. 3 shows a second embodiment of the present invention, in which three magnets 26, 27, and 28 are arranged outside a container 25, and a coil 29 is attached only to the magnet 27.

FIG. 3a shows the erased state as a display, and the magnets 26, 27, and 28 have the same magnetization direction, and the magnetic fine particles 24 are connected to the shielding plates 30, 31, and 32, and the magnet 26.
, 27, and 28, respectively. This state can also be achieved by moving the permanent magnet 14 as shown in FIG. 1d. FIG. 3b shows a state in which the magnetization of the magnet 27 is reversed by energizing the coil 29, and the magnetic fine particles 2
4 rests between the magnets 26 and 27 between the magnets 27 and 28, and the display is in a writing state. The second embodiment is considered to be more effective when used in large-sized displays than the first embodiment. FIG. 4 shows a third embodiment of the present invention, in which magnets 34, 3 are placed on the outside of the container 33.
A coil 36 is attached to the magnet 35, and a magnet 37 is arranged opposite the magnet 35.

FIG. 4a shows the erased state as a display. In FIG. 4a, the magnetization directions of the magnets 34, 35, and 37 are the same, and the magnetic fine particles 38 are
It remains stationary between the magnets 35 and 37 due to mutual magnetic force. This state can also be achieved by moving the permanent magnet 14 as shown in FIG. 1d. FIG. 4b shows a state in which the magnetization of the magnet 35 is reversed by the coil 36, the magnetic fine particles 38 are stationary between the magnet 34 and the magnets 35 and 37, and the display is in a writing state. FIG. 5 shows a fourth embodiment of the present invention, in which magnets 40, 4 are placed on the outside of the container 39.
1 are arranged, and coils 42 and 43 are attached to each.

Further, magnets 44 and 45 are arranged opposite to the magnets 40 and 41. In FIG. 5a, facing magnets 40
, 44 and the magnets 41, 45 are the same, but the magnets 40, 41 are magnetized in opposite directions. In this case, the magnetic fine particles 46 are placed between the magnets 40 and 44 and between the magnets 41 and 45.
The display is in a blank state. FIG. 5b shows magnets 40 and 41 connected to coils 42 and 4, respectively.
3, the magnetization is reversed by magnetic fine particles 46.
is stationary between magnets 40, 44 and magnets 41, 45, and the display is in a writing state. Compared to the first and second embodiments, the third and fourth embodiments have a structure in which a magnet is disposed in the shielding plate portion, so that the magnetic effect is strengthened and the effect as a high-speed display is large.

As described above in detail with the embodiments, the present invention erases and writes characters and figures on magnetic particles in a liquid by the action of a magnet and a coil, and is easy to rewrite, has a memory function, and can be mass-produced. It has advantages such as low cost, resistance to aging, etc., and is suitable for large and small displays and can be used in a wide range of applications.

[Brief explanation of the drawing]

FIG. 1 shows a first embodiment of the present invention, in which FIG. 1a is a top perspective view with no display;
Figure b is a sectional view taken along the line A-A in Figure 1a, Figure 1c is an explanatory diagram of the coil arrangement, Figure 1d is an erased view of the permanent magnet display, and Figure 1e is the displayed state. top perspective view of
Fig. 1f is a sectional view taken along line B-B in Fig. 1e, Fig. 2 shows an assembly of display elements, Fig. 2a is an example of its display, and Fig. 2b is a 3A is a cross-sectional view taken along the line C-C in FIG. 3, which shows a second embodiment of the present invention, in which FIG. 3A shows an erased state, FIG. 3B shows a written state, FIG. 4 shows a third embodiment of the present invention, in which FIG. 4a shows an erased state, FIG. 4b shows a written state, and FIG. 5 shows a third embodiment of the present invention. Embodiment 4 is shown in which FIG. 5a shows an erased state, and FIG. 5b shows a written state. 1, 18, 24, 38, 46...magnetic fine particles, 2,
17...Liquid, 16...Protrusion, 3,15,
25, 33, 39... Container, 4, 5, 19, 20, 26
,27,28,34,35,37,40,41,44,
45...Magnet, 6, 12, 21, 29, 36, 42, 4
3...Coil, 7, 8, 22, 30, 31, 32...
·Shield. Figure 'o Figure - Figure b Figure - Figure c Figure l Figure d Figure - Figure e Figure - Figure f Figure 2. Figure 2b Figure 3o Figure 3b Figure 4o Figure 4b Figure 5o Figure 5b

Claims (1)

[Claims] 1. A planar container in which a plurality of element units are formed by forming lattice-like protrusions on a flat plate that can transmit light, and each element unit is filled and sealed with a colloidal liquid consisting of a liquid and magnetic fine particles; a magnet arranged at one end or both ends of each element unit on one side of the planar container; and a coil arranged at the other end or intermediate part of each element unit on the same side of the planar container corresponding to the magnet. What is claimed is: 1. A magnetic display device comprising a magnet with a coil, and writing and erasing of each element is performed by reversing the magnetization of the magnet with a coil.