JPS6156592B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a magnetic bubble memory device. Generally, magnetic thin films have magnetic domains with easy magnetization axes in the in-plane direction, but in some types of magnetic thin films, such as orthoferrite and magnetic garnet, magnetic domains have easy magnetization axes perpendicular to the film plane. When no external magnetic field is applied to this thin film, the magnetic domains with upward magnetization direction and the magnetic domains with downward magnetization direction alternate in a striped pattern with approximately equal area. As the magnetic field is added, the upward magnetic domain becomes narrower, the downward magnetic domain expands, and finally the upward magnetic domain becomes a cylindrical magnetic domain with a diameter of several micrometers. This cylindrical magnetic domain is called a bubble domain. Since the bubble domains can be moved freely within the magnetic thin film due to the gradient of the magnetic field, magnetic bubble memory devices utilize these bubble domains as memory elements. FIG. 1 shows an example of this magnetic bubble memory device. To briefly explain this, the chip 1 is mounted on an insulating substrate 2, and drive coils 3 and 4 are provided around it orthogonally to give a horizontal rotating magnetic field to the chip 1, and these are molded. Alternatively, it is inserted into the resin case 5 and is further inserted into a shield case 9 which also serves as a yoke together with the bias magnet 7 and the magnetic shunt plate 8 which are fitted into a mold or a recess formed on the outside of the resin case 5. .

In this way, in the magnetic bubble memory device, the bias magnet 7 and the magnetic shunt plate 8 are bonded with adhesive, and then bonded to the recessed part of the resin case 5 with adhesive, and then an adhesive is applied thereon. The shield case 9 is loaded. Therefore, in such a magnetic bubble memory device, a layer of adhesive is formed between the bias magnet 7 and the magnetic shunt plate 8, and between the bias magnet 7 and the shield case 9, and the thickness of the adhesive layer is Causes variation. This causes variations in the magnetic resistance of the magnetic circuit and variations in the heat dissipation effect. The present invention has been devised to improve this drawback.

For this reason, the present invention includes a resin case into which a magnetic bubble memory chip and a coil for driving the bubbles of the chip are inserted, and a bias magnet and a magnetic shunt plate fitted into a recess formed on the outside of the resin case. In a magnetic bubble memory device that is inserted into a shield case that also serves as a yoke, a bias magnet and a magnetic shunt plate are inserted into the recesses of the resin case, and then the resin case is inserted into the shield case, and then it is removed from the outside. By magnetizing the bias magnet, the bias magnet and the magnetic shunt plate are bonded to the shield case by magnetic force, and then a filler is injected into the gap between the shield case and the resin case to close the bias magnet. and fixing the magnetic field shunt plate.

Embodiments of the present invention will be described in detail below based on the accompanying drawings.

FIG. 2 shows an exploded perspective view of a magnetic bubble memory device assembled by the method of the present invention. However, the chip, insulating board, and coil inserted into the resin case are not shown. In the figure, reference numeral 10 is a resin case, 11, 11' are bias magnets, 12,
12' is a magnetic field shunt plate, and 13 is a shield case that also serves as a yoke. The resin case 10 has holes 10a for inserting chips, insulating substrates, coils, etc., and bias magnets 11, 11' and magnetic shunt plates 1.
A recessed portion 10b into which the portions 2 and 12' are fitted is formed. Each of these members is assembled in the following manner.

First, the insulating board with the chip mounted thereon and the coil are inserted and fixed into the hole 10a of the resin case 10, and then the magnetic shunt plate 12 or 1 is inserted into the recess 10b of the resin case 10.
2' and the bias magnet 11 or 11' are fitted together and inserted into the shield case 13 in this state. Thereafter, the bias magnets 11, 11' are magnetized from outside the shield case 13, and the bias magnets 11, 11' and the magnetic shunt plates 12, 12' are brought into close contact with the shield case 13 by the magnetic force. Next, as shown in FIG. 3, a filler 14 is injected into the grooves 10c and 10c' of the resin case 10 to fill the gaps between the recess 10b of the resin case 10, the bias magnet 11 or 11', and the magnetic shunt plate 12 or 12'. do.

The magnetic bubble memory device assembled in this way includes a shield case 13 and a bias magnet 1.
1, 11', and bias magnet 1
Since there is no adhesive or filler between the magnetic field shunt plates 1, 11' and the magnetic field shunt plates 12, 12', heat conduction is good, magnetic resistance is reduced, and variations in these are also reduced. Furthermore, it is safe against vibrations because it is fixed by the filler 14.

As explained above, the method for manufacturing a magnetic bubble memory device of the present invention improves the heat dissipation and magnetic properties of the magnetic bubble memory device by using magnetic force to bond the shield case, the bias magnet, and the magnetic shunt plate. Furthermore, by omitting the bonding process using adhesive, it is possible to reduce assembly man-hours.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an example of a conventional magnetic bubble memory device, FIGS. 2 and 3 are diagrams for explaining an embodiment of the present invention, and FIG. 2 is an exploded perspective view of the magnetic bubble memory device. FIG. 3 is an assembled sectional view thereof. 10... Resin case, 11, 11'... Bias magnet, 12, 12'... Magnetic shunt plate, 13...
Shield case, 14...Filling material.

Claims (1)

[Claims] 1. A resin case into which a magnetic bubble memory chip and a coil for driving the bubbles of the chip are inserted;
In a magnetic bubble memory device, a bias magnet and a magnetic shunt plate fitted into a recess formed on the outside of the resin case are inserted into a shield case that also serves as a yoke. After fitting the magnetic shunt plate, the resin case is inserted into the shield case, and then the bias magnet is magnetized from the outside, and the bias magnet and the magnetic shunt plate are bonded to the shield case by magnetic force. . A method of manufacturing a magnetic bubble memory device, which comprises: thereafter injecting a filler into the gap between the shield case and the resin case to fix the bias magnet and the magnetic shunt plate.