JPH05334636A - Magnetic head and method for adjusting height of magnetic head - Google Patents

Abstract

PURPOSE:To enable the adjustment of a track height after adhesion of head chips to be carried out by constituting a head base of the construction laminated with ray absorbing members and a glass base material and irradiating the ray absorbing members with rays, thereby causing the bending deformation of the head base. CONSTITUTION:Chromium is deposited by evaporation on both surfaces of the base material 1a consisting of quartz glass to form the ray absorbing members 1b, 1c, by which the head base 1 having the laminates structure is formed. Further, the side irradiated with lasers of an arrow A is provided with window parts 2 by etching to expose the glass base material 1a. The head chip adhering part of the base 1 is divided by slits to the parts for plural pieces of the head chips and the head chips 3 are adhered thereto by an epoxy resin. The base 1 is bent and deformed to the side irradiated with the lasers if the base exclusive of the window parts 2 is irradiated with the YAG laser beams B1 to B3. The base is bent and deformed to the opposite direction if the window parts 2 are irradiated with the laser beams B4 to B6. Then the respective head positions are matched with the target values.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the structure of a magnetic head used in a magnetic recording / reproducing apparatus.

[0002]

2. Description of the Related Art In recent years, a multi-channel head using a plurality of heads has been put into practical use in order to simultaneously record and reproduce a large amount of signals in a digital VTR or the like.

In a multi-channel head, it is necessary to accurately match the track heights of a plurality of head chips (the positions of the gap ends of the head chips).

In the case of the head directly fixed to the cylinder, the head base is usually pushed up by a screw provided on the cylinder for adjustment.

Further, in the dynamic tracking system in which the reproducing head is attached to a driving means such as a bimorph and is controlled so as to follow the recording track according to the rotation of the cylinder, since the head is attached to the tip of the bimorph, the height adjusting screw is used. Since it is not possible to provide the target track height by cutting the head chip accurately, measuring the size from the end surface of the head chip to the gap end, selecting the head chip with the correct size and adhering it to the head base. Is gaining

[0006]

However, in the above-mentioned conventional technique, when the gap pitch between the head directly fixed to the cylinder and the adjacent head chip is narrowed, the place where the height adjusting screw is provided in the cylinder is narrowed. Therefore, adjustment with screws is difficult.

When the track pitch for recording / reproducing becomes narrower, the track height accuracy of the head is required to be 1 μm or less. However, it is difficult to obtain a target track height with a high yield simply by measuring the dimensions of the head chip and adhering it as described above, due to variations in the thickness of the adhesive, inclination of the end surface of the head chip, and the like.

The present invention solves the conventional problems, and an object of the present invention is to provide a head structure that enables adjustment of the track height after adhesion and a method therefor.

[0009]

In order to achieve this object, the present invention provides a plurality of head chips for recording and reproducing,
A magnetic head comprising a head base into which a head chip bonding portion for connecting them is divided, wherein the head base has a structure in which a light absorbing member and a glass base material are laminated, and the light absorbing member absorbs light rays. It is characterized in that each head position is adjusted to the target value by directly or through the glass base material, irradiating and heating, and bending and deforming the irradiated part as a boundary.

[0010]

When the head base composed of the light absorbing member and the glass base material is irradiated with YAG laser light or the like, the laser light is absorbed by the light absorbing member, and the interface between the glass base material and the light absorbing material is heated to a high temperature in a short time. The head base is melted and solidified, and due to the strain generated at that time, the head base is bent and deformed at the laser irradiation portion. Therefore, the track height can be accurately adjusted by appropriately controlling the laser output and the focus distance.

A window portion is provided on the surface of the glass base material of the head base on the laser light irradiation side so that the glass base material is exposed, and a light absorbing member is provided. By stacking the members, the bending direction of the head base can be changed without changing the laser light irradiation direction. More specifically, the head base can be bent and deformed toward the laser light irradiation direction by directly irradiating the light absorbing member with the laser light while avoiding the window provided in the head base. When the window portion provided on the head base is irradiated, the laser light passes through the glass base material and is absorbed by the light absorbing member on the surface facing the window portion, so that the head base is bent and deformed in the direction opposite to the laser light irradiation direction. Can be made.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. FIG. 1 is a perspective view of a magnetic head of the present invention. Reference numeral 1 denotes a head base, which has a laminated structure in which metal chrome is formed on both surfaces of a glass base material 1a using quartz glass by vapor deposition to form light ray absorbing members 1b and 1c. Further, the light absorbing member 1b on the YAG laser irradiation side indicated by arrow A is provided with a window 2 by etching, and the glass base material 1a is exposed. A head chip 3 is attached to the head base 1 with an epoxy resin. The head chip bonding portion of the head base 1 is divided by the slits 4 into the number of head chips.

As the material of the light absorbing member, the example of chrome is shown in this embodiment, but as the metal material, aluminum or the like, or ceramic material such as silicon oxide can also be used.

In this embodiment, the exposed portion of the glass member is a window, but it may be in the form of a strip connected to adjacent window portions.

Next, a method of adjusting the track height of the magnetic head having the above structure will be described with reference to FIGS. FIG. 2 is a perspective view showing a deformed state of the head base, in which the shape of the head base before the deformation is indicated by a broken line and the shape of the head base after the deformation is indicated by a solid line, and FIG. 3 shows a bending deformation method of the head base.

In FIG. 2A, arrows B1, B2, B
Reference numeral 3 indicates the position and direction of the YAG laser light with which the light absorbing member 1b is directly irradiated while avoiding the window 2 provided in the head base 1, and the head base 1 before deformation indicated by the broken line is indicated by the solid line. In addition, it is bent and deformed in the direction of the YAG laser irradiation side.

In FIG. 2B, arrows B4, B5, B
Reference numeral 6 indicates the position and direction of the YAG laser light emitted to the window 2 provided in the head base 1. The undeformed head base 1 shown by the broken line is in the opposite direction to the YAG laser irradiation side as shown by the solid line. It is bent and deformed.

In FIG. 3, reference numeral 5 denotes a piezoelectric ceramic element in which two plates of barium titanate or the like used for dynamic tracking are sandwiched, for example DC50.
A displacement of about 50 μm can be obtained at 0V. Head chip 3
The head base 1 to which is adhered is adhered to the piezoelectric ceramic element 5 with an epoxy resin or the like. here,
The head chip 3 is precisely cut so that the dimension from the head end surface to the gap end portion becomes a target value when a gap-formed rod composed of a plurality of head chips is in a state. Next, after the magnetic tape sliding surface of the head chip 3 is polished, the head chip 3 is positioned and adhered on the head base 1 so that the gap distance, the protrusion amount, and the direction of the sliding surface have target values. Here, the position of the head gap end of the bonded head chip 3 could be secured within ± 5 μm with respect to the target dimension from the surface of the head base 1. Next, the piezoelectric ceramic element 5 is attached to the upper cylinder 6 so that the positional relationship such as the protrusion amount of the head chip 3 from the upper cylinder 6 becomes accurate.

The observation microscope 7 and the monitor television 8 are used to measure the distance TH from the predetermined position 9a of the lower cylinder 9 to the head gap end 10. YA so that the distance TH is set for each head chip
The G laser light 11 is applied to a predetermined position of the head base 1, and the YAG laser light irradiation side or the opposite side is bent and deformed to adjust the height to a target value. Here, the YAG laser light 11 is passed through a hole 6a provided in the upper cylinder 6 corresponding to the irradiation portion of the head base 1, and the surface of the light absorbing material of the head base 1 (or the surface of the glass base material exposed in the window portion). ), Adjust the laser beam diameter by defocusing and
The distance TH could be adjusted to 1 μm or less with respect to the target value by selecting conditions such as energy adjustment of J or less and irradiating. Also, the azimuth angle can be adjusted by shifting the irradiation position with respect to the center of the head chip and adjusting it.

In this embodiment, the case of using dynamic tracking in which the head base is bonded to the piezoelectric ceramic element has been described, but it is also possible to use a fixed type in which the head base is directly bonded to the upper cylinder. In the head base of the embodiment, the tip is separated by the slit and the original is 1.
Although an example in which they are connected to each other is shown, there is no problem even if the original part is divided for each head chip.

[0021]

As described above, according to the present invention, the head base has the laminated structure of the light absorbing material and the glass base material,
The head base can be bent and deformed in the laser light irradiation direction side or the opposite side by providing a window portion without the light absorbing material on a part of the light absorbing material and exposing the glass base material. The head height can be adjusted with high accuracy and high yield. Further, since the glass base material of the head base has a specific gravity of 2.5, which is smaller than the specific gravity of aluminum of light metal of 2.7, and can be quantified, it is possible to easily obtain the amplitude by mounting it on the dynamic tracking drive means. it can.

[Brief description of drawings]

FIG. 1 is a perspective view of a magnetic head of the present invention.

FIG. 2A is a perspective view showing a deformed state of the present invention. FIG. 2B is a perspective view showing a deformed state of the present invention.

FIG. 3 is a perspective view showing the height adjustment of the head of the present invention.

[Explanation of symbols]

 1 Head Base 1a Glass Base Material 1b Light Absorbing Member 1c Light Absorbing Member 2 Window 3 Head Chip 4 Slit

Claims (4)

[Claims] 1. A magnetic head comprising a plurality of head chips for recording / reproducing and a head base into which a head chip bonding portion for connecting the head chips is divided, the head base including a light absorbing member and a glass base material. A magnetic head having a laminated structure of. 2. The magnetic head according to claim 1, wherein the light absorbing member is made of a metal material or a ceramic material. 3. The magnetic head according to claim 1, wherein a window portion is provided in a part of the light absorbing member, and the glass base material is exposed. 4. A light ray is directly applied to a light ray absorbing member, or
A height adjusting method of a magnetic head, characterized in that each head position is adjusted to a target value by transmitting through a glass base material, irradiating and heating, and bending and deforming the irradiated portion as a boundary.