JPS6230174Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic head, and particularly to a head in which a thin film magnetoresistive magnetic head chip is accurately loaded into a post.

In a post-type MR head in which a magnetoresistive magnetic head (hereinafter simply referred to as MR head) chip is incorporated into a conventional post, its positioning,
For fixing, insert square hole 2 into post 1 as shown in Figure 1.
A method is used in which a head chip 3 is inserted into the head chip. However, the square hole 2 itself is quite difficult to form with high precision. Furthermore, since the thin film pattern surface 4 of the MR head is inserted into the square hole 2 in contact with the inner surface thereof, there are problems such as the protective film on the thin film pattern surface 4 being torn. Furthermore, during assembly, the head chip 3 was completely removed from the square hole 2.
This caused problems such as the assembly accuracy could not be confirmed after the chip was inserted, and this led to variations in the characteristics of the finished product.

The present invention improves the conventional method of fixing a head chip using a square hole, and is easy to manufacture and does not damage the thin film pattern surface of the head chip.
The present invention provides a post-type MR head that can be assembled while checking assembly accuracy.

An embodiment of the present invention will be described in detail below with reference to the drawings.

Figure 2 shows the overall configuration of a post-type MR head. A non-magnetic metal film 6 is wrapped around the portion of the post 5 that comes into sliding contact with the magnetic tape, and a head chip is sealed inside the post 5 with resin. In addition, 7
is the lead wire connected to the head chip.

FIG. 3 is a detailed view of the head chip assembly. The non-magnetic film 6 is wrapped tightly around the post 5 and fixed with adhesive, and its ends are welded to form a magnetic tape sliding portion. The head tip 8 is attached to a stepped portion 12 of the post 5, which will be described later, and is adhered while being pressed by a presser plate 9. The tip thereof is fixed at a position where it contacts the inner surface of the non-magnetic metal film 6. A lead wire 7 is soldered to the rear of the head chip 8. After being assembled in this state, the space portion (lead extraction portion) 15 is sealed with resin.

FIG. 4 is a perspective view of the post 5. Notch part 1
0 is the "barge" at the tip of the cap screw when attaching and fixing the entire post-type MR head to the device to be used. The upper slope 11 has the function of acting as a "shade" for the magnetic tape when inserting the magnetic tape and the function of indicating the direction of the post 5. post 5
The notch 12 in the center of the front face is for inserting and positioning the head tip 4, and its width W ₁ and step A are such that the head tip 4 is flush with the upper surface 13 without any gap. ing.
The upper surface 13 is the adhesive part of the presser plate 9, and its width is
W ₂ is wider than W ₁ . The cutout portion 14 is
This is a "edge" for assembling the head tip 8 and the presser plate 9, and is formed by cutting off approximately one-fourth of the circumference of the post 5, and the cutout 12 is provided on the bottom of the post 5. There is. A hollow portion 15 on the rear surface of the post 5 is a portion for drawing out the lead wire 7 and fixing it with resin.

FIG. 5 is a detailed view of the head chip 8. The width 17 and thickness 18 of the substrate 16 correspond to the notch 1 of the post 5.
2, the MR element 20, leads 21, and terminals 21 are formed by vapor deposition on one main surface 19, and the insulating protective film 22 is formed in the area indicated by the broken line. is deposited in the area. The lead wire 7 is soldered to the rear end of the vapor-deposited lead terminal 21.

The position of the MR element 20 is determined by accurately controlling the dimension 23 from the tip of the substrate 16.

Next, the assembly procedure will be explained.

After a plurality of MR elements 20 and lead terminals 21 are vapor-deposited on one substrate (not shown), this substrate is cut to a predetermined size to produce a head chip 8, and the MR element 20 is inserted from the tip of the head chip 8. The tip of the head tip is finished by accurately controlling the dimension 23 up to. The lead wire 7 is soldered to the rear end of the lead terminal 21 of the head chip 8 completed above to form a head chip unit.

The completed head chip unit is inserted into the notch 12 of the post 5 together with adhesive, and the presser plate 9 is covered at the same time. With the dimension from the MR element 20 to the outer peripheral surface of the post 5 accurately positioned using a microscope, the adhesive is cured by heating at a temperature of 80 to 100°C.

Next, a non-magnetic metal film 6 is wrapped around a predetermined position and fixed to complete the process. With the above structure, the tape sliding surface, which has a large effect on playback characteristics, can be
The dimensions up to the MR element can be accurately managed.

As mentioned above, an arc-shaped cavity is provided on the front side of the post leading to the lead pull-out section on the rear side, and a step is provided in this cavity for positioning the head tip. You can get the following effect.

(1) There is no risk of the vapor deposited film of the head chip coming into contact with the post during assembly, so there is no problem such as the protective film being torn.

(2) Since the set position of the MR element can be confirmed using a microscope, variations in the distance from the magnetic tape contact surface to the MR element can be reduced.

(3) Since the notch is formed by providing a step in the notch cavity, the machining accuracy is high.
The MR element of the head chip can be reliably positioned on the center line of the post.

(4) Even if the dimensions from the tip of the head chip to the MR element vary depending on the head chip itself, the position can be adjusted accurately during assembly.

(5) During assembly, the head chip can be loaded from above the cutout cavity, so assembly can be easily automated.

(6) After fixing the head chip to the post, it is possible to observe the quality of the vapor-deposited surface of the head chip before resin sealing.

As described above, since high-precision assembly can be efficiently realized, variations in output characteristics due to assembly can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the structure of the main parts of a conventional magnetic head, FIG. 2 is an overall configuration diagram of an embodiment of the magnetic head according to the present invention, FIG. 3 is a perspective view of the main parts, and FIG. The figure is a perspective view showing the structure of the post before the head chip is assembled, and FIG. 5 is a perspective view of the head chip unit. 5...Post, 6...Nonmagnetic metal film, 7
... Lead wire, 8 ... Head chip, 9 ... Pressing plate, 12 ... Step portion, 13 ... Upper step surface, 14 ...
Notch portion, 15...Cavity portion, 16...Substrate, 2
0... Magnetoresistive element, 21... Lead terminal,
22...Insulating protective film.

Claims (1)

[Scope of utility model registration request] A part of the front surface of the post is provided with an arc-shaped notch cavity having a width slightly wider than the head tip width and communicating with the lead pull-out portion on the rear surface of the post, and the bottom surface of the cavity is provided with a notch cavity having a width slightly wider than the head tip width. A magnetic head characterized in that a step portion is provided such that the thin film pattern surface is located on the center line of the post, and the head chip is fixed to the step portion.