JPH04170710A - Magnetic head for floppy disk device - Google Patents

Abstract

PURPOSE:To reduce the resistance at the time of fitting of a back core and thereby make the fitting smooth by providing a slant such that the thickness of the back core decreases toward the front side in the direction of insertion, in a corner part on the insertion side. CONSTITUTION:A back core 11 is formed of a magnetic material in the shape of a rod, and a slant 11d tilted at an angle theta is formed in a part wherein a lateral surface 11b on the opposite side to a lateral surface 11a to be brought into contact with a front core 1 so that it faces the latter intersects a lower surface 11c. The slant 11d is positioned at the part which is a corner part on the side of insertion of the core 11 into a back core holding part of a spring 3 and whereat the core 11 is brought into pressure contact with a pressing piece 5. The slant 11d is so tilted that the thickness of the core 11 decreases gradually toward the lower surface 11c side. When a magnetic head is assembled by using this core 11, the core 11 is fitted in the back core holding part of the spring 3 retained temporarily by the core 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic head used in a floppy disk drive, and particularly to the structure of a back core forming a part of the magnetic head.

[Conventional technology]

Conventionally, the magnetic head of a floppy disk device was
Some have a back core that is held in pressure contact with a front core by a leaf spring. This type of magnetic head will be explained with reference to FIGS. 3 and 4.

FIG. 3 is a perspective view showing a conventional magnetic head for a floppy disk device, and FIG. 4 is an enlarged side view showing a part of the conventional magnetic head for a floppy disk device in which a puncture core is attached. In these figures, numeral 1 denotes front cores in contact with a magnetic recording medium (not shown), and three front cores are arranged in a row. Note that 1a indicates a contact portion that comes into contact with the magnetic recording medium. 2 is a rod-shaped back core that spans all of these front cores 1 and forms a magnetic circuit together with the front cores 1; this back core 2 is formed with a rectangular cross section;
It is held in pressure contact with the front core 1 by a spring 3, which will be described later.

The spring 3 includes a flat plate part 4 that is in contact with one side of the front core 1, and a pressing piece 5 that is formed in series on the flat plate part 4 and forms a hack core holding part with a U-shaped cross section together with the flat plate part 4.
It is formed from. As shown in FIG. 4, the pressing piece 5 is formed to have an oval-shaped cross section, and a portion parallel to the flat plate portion 4 is bent to have a dogleg-shaped cross section. The upper end portion thereof is inclined so as to gradually move away from the flat plate portion 4 toward the upper side. Two pressing pieces 5 are provided so as to intervene between the three front cores 1.

Next, a procedure for assembling the conventional magnetic head configured as described above will be explained. First, as shown in FIG. 4, the springs 3 are temporarily held on the three front cores 1 arranged in a row. At this time, the two pressing pieces 5 of the spring 3
is interposed between the front cores L. Then, the back core 2 is pushed into the back core holding portion of the spring 30 from above (the side opposite to the contact portion 1a of the front core 1).

When pushing in, insert one side of back core 2 into front core 1.
At the same time, the other side surface is brought into sliding contact with the pressing piece 5, and the pressing piece 5 is pushed and spread. The hack core 3 is installed by simultaneously pushing the hack core 3 into two hack core holding parts.

[Problem B to be Solved by the Invention] However, in the conventional magnetic head configured as described above, when pushing the back core 2 into the back core holding portion of the spring 3, the pressing piece 5 has a lower corner of the hack core 3. Since the corners first come into contact, the pressing pieces 5 must be pushed and spread at these corners. For this reason, there was a problem in that the resistance increased, making it difficult to insert the back core 2 into the back core holding portion, and the working time becoming longer. Moreover, if the hack core 2 was forced in, the front core 1 sometimes broke.

[Means to solve the problem]

The magnetic head for a floppy disk device according to the present invention includes:
At the corner of the back core on the side where the leaf spring is inserted into the clamping part and pressed against the elastic piece of the clamping part, an inclined surface is provided so that the thickness of the hack core becomes gradually thinner toward the front in the insertion direction. It is something.

[For production]

When the hack core is attached, the inclined surface provided on the hack core first comes into contact with the elastic piece, and when the hack core is pushed into the holding part of the leaf spring, the elastic piece is pushed and spread out while sliding on the inclined surface. Therefore, the resistance when attaching the back core is reduced.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2.

FIG. 1 is a perspective view of a back core used in the magnetic head for a floppy disk device according to the present invention, and FIG. 2 is a side view showing an enlarged view of the back core mounting section in the magnetic head for a floppy disk device according to the present invention. It is. In these figures, the same or equivalent members as those explained in FIGS. 3 and 4 are given the same reference numerals and detailed explanations will be omitted. The magnetic head according to the present invention has an M-structure except for the shape of the back core, which is different from the conventional one. In FIGS. show. This hack core II is formed into a rod shape from a magnetic material, and has a side surface 11b opposite to a side surface 11a that is in contact with the front core 1, and a lower surface (surface on the magnetic recording medium side) 11c.
An inclined surface 11d inclined at an angle θ is formed at the intersection of the two. The inclined surface 11d is positioned at a corner of the back core 11 on the side where the spring 3 is inserted into the back core holding portion, and is in pressure contact with the pressing piece 5. This inclined surface lid is inclined so that the thickness of the back core 11 becomes gradually thinner toward the lower surface 11c side (the front side in the direction of insertion into the back core holding portion).

In order to assemble a magnetic head using the back core 11 configured as described above, the back core 11 is attached to the back core holding portion of the spring 3 temporarily held on the front core 1 in the same manner as in the conventional method. The work of installing the hack core 11 is carried out by placing the side surface 11a in sliding contact with the front core 1 with the inclined surface forming part facing down. When the hack core 11 is brought into contact with the front core 1 and pushed down, the inclined surface lid first comes into contact with the pressing piece 5 of the spring 3. When the hack core 11 is further pushed into the back core holding portion, the pressing pieces 5 slide on the slope lid and are pushed and spread by the slope lid.

Therefore, the resistance when attaching the back core is reduced, and the hack core 11 can be attached smoothly without sudden stress being applied.

〔Effect of the invention〕

As explained above, the magnetic head for a floppy disk device according to the present invention has a plate spring in a corner part of the back core on the side where the plate spring is inserted into the clamping part, and which is in pressure contact with the elastic piece of the clamping part. Because we created an inclined surface where the thickness of the back core gradually becomes thinner as you move towards it,
When the back core is attached, the inclined surface provided on the back core first comes into contact with the elastic piece, and when the back core is pushed into the holding part of the leaf spring, the elastic piece is pushed and spread out while sliding on the inclined surface. Therefore, the resistance when attaching the back core is reduced, and the hack core can be attached smoothly without stress being applied in sudden heat.

Therefore, the back core mounting work can be carried out in a short time, and the front core can be reliably prevented from breaking due to the back core mounting work, thereby improving the yield of the assembly. Furthermore, it is possible to prevent deterioration of characteristics such as reproduction output and resolution due to cracks, etc., and the yield in characteristic inspection is also improved.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a back core used in the magnetic head for a floppy disk device according to the present invention, and FIG. 2 is a side view showing an enlarged view of the back core mounting section in the magnetic head for a floppy disk device according to the present invention. It is. FIG. 3 is a perspective view showing a conventional magnetic head for a floppy disk device, and FIG. 4 is an enlarged side view showing a back core mounting portion in a conventional magnetic head for a floppy disk device. ■...Front core, 3...Spring, 5.
...Press piece, 11...Back core, lid...
・Slope surface.

Claims (1)

[Claims] Multiple front cores are lined up in contact with the magnetic recording medium,
In a magnetic head for a floppy disk device, in which a back core spanning all the front cores is held in pressure contact with the front core by a leaf spring having a gripping portion having a substantially U-shaped cross section into which the back core is inserted. The back core is characterized in that an inclined surface is provided at a corner part on the insertion side of the clamping part, which is pressed against the elastic piece of the clamping part, so that the thickness of the back core becomes gradually thinner toward the front in the insertion direction. A magnetic head for floppy disk drives.