JPH03288311A - Magnetic head and production thereof - Google Patents

Abstract

PURPOSE:To extremely decrease the fluctuations in the track height occuring in the thickness of an adhesive, etc., by providing parts where the adhesive is absent between a base plate stuck with a head chip and a head base and adjusting the track height in these parts. CONSTITUTION:A groove 6 is formed on the surface of the base plate 2 to be adhered to the head base 1. The adhesive does not exist at the boundaries between the surfaces 5 at both ends and the head base 1 where the respective surfaces are in contact with each other. The head exactly determined with the track height from the surface 8 of the head base 1 is, therefore, obtd. if the size h form the end faces 5 of the base plate 2 up to the bottom end 7 of the magnetic gap of the head chip 3 is exactly adjusted. The position of the magnetic gap end 7 is based on the surface 8 of the head base 1 if such head is mounted to the cylinder of a VTR and, therefore, the track height of the plural heads is exactly controlled to the prescribed value and the need for height adjustment is eliminated. The stage for assembling cylinders is thus greatly simplified.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic head in which the position of the gap of the head chip is controlled with high precision with respect to the head base, and a method of manufacturing the same.

BACKGROUND ART In a recording/reproducing device in which a cylinder rotates, such as a VTR, the positions of the gaps between the plurality of magnetic heads on the cylinder are such that, for example, the lower end of the gap is located on a plane perpendicular to the axis of rotation of the cylinder. adjusted. Since the head chip is attached to the cylinder mounting surface of the head base, the distance from this surface to the bottom of the gap is 11 (1
-Rank height) can be adjusted by using a spacer inserted between the head base and cylinder, or by pressing with a screw protruding from the cylinder! One verse is said.

Problems to be Solved by the Invention When a large number of heads are mounted close to each other on a cylinder, the structure in which the track height is adjusted by protruding screws from the cylinder has significant dimensional limitations. Furthermore, when mounting a head on a piezoelectric bimorph element for special playback, the overall weight of the head including the track height adjustment mechanism is limited due to the driving force of the piezoelectric element, and this is combined with dimensional constraints. This makes it difficult to realize such a system.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a base to which a head chip is bonded, and a base that is joined to the base with at least a portion in contact without using an adhesive. It is characterized in that the magnetic head is constructed from a head base.

Function: Since the head of the present invention has a part without adhesive between the base to which the hentochinob is attached and the head base, it is possible to adjust the trunk height in this part after the head tip is attached to the base. , variations in track height caused by the thickness of the adhesive, etc. that occur at the bonded portion can be greatly reduced. With a head configured like this, the track height from the cylinder mounting surface of the head base is regulated with high precision, so there is no need to adjust the trunk height after the head is mounted on the cylinder, making it easier to assemble the cylinder. The process becomes easier. Furthermore, if a piezoelectric bimorph element is used as the head base, it becomes possible to realize a head with a very lightweight structure in which a plurality of head chips have the same track height.

EXAMPLE A first example of the magnetic head of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 1 is a perspective view of the head of the present invention, and FIG. 2 is a front view seen from the direction of arrow A in FIG. The head chip 3 is glued to the base 2 with adhesive 4, and the base 2 is attached to the base 2.

It is joined to the dohes 1. Head base 1 of base 2
A groove 6 is formed on the surface to be joined with the surface 5 at both ends.
There is no adhesive at the interface between the head base 1 and the head base 1, and their respective surfaces are in contact with each other.

Therefore, if the dimension from the end surface 5 of the base 2 to the lower end 7 of the magnetic gap of the head chip 3 is accurately determined in advance, the trunk height from the surface 8 of the head base L can be determined accurately. You will get the head. When such a head is attached to a VTR cylinder, the position of the magnetic gap end 7 is based on the surface 8 of the head base 1, so the track height of the plurality of heads on the cylinder is accurately set to a predetermined value. This eliminates the need for a section with a height of m, and greatly simplifies the cylinder assembly process. In addition, even if the head base is a piezoelectric bimorph element for auto-tracking, if you attach a base with adjusted track height, it will be extremely lightweight and you can create a head equipped with multiple hendochins with matching track heights. Obtainable.

FIGS. 2 and 3 show the method for manufacturing the head of the present invention.
This will be explained based on the diagram. After the head chip 3 with a radius of 160 μm is adhered to the base 2 with an Epoquin adhesive, the dimension from the end face 5 of the base to the lower end of the gap is measured on the measurement stage 9 (FIG. 3).

h is made smaller than the target dimension, divided into layers according to the film thickness required for the target value, and then a thin film of chromium, quartz, etc. is deposited on the bottom surface 5 of the base 2 using a sputtering device or the like. By doing so, it is possible to easily and highly accurately match h to the target dimension within 1 μm. After positioning this base on the head mousse 1, the surface 8 of the head base 1 is
and the end surface 5 of the base 2 are bonded with an epoxy adhesive 10 so that no adhesive enters the interface. Since nothing is present at the interface between the head base 1 and the base 2, the target value of the dimension from the surface 8 of the head hesse 1 to the lower end 7 of the gap is accurately reproduced. For this reason, the trunk height of the head chip joined to the head base can be very closely matched to the design value, and when multiple heads are installed on the Soriadder, the track height of each head can be increased without adjustment. Match precision.

In the above embodiment, a method was described in which the thickness of the base was made smaller and a thin film was formed to cover the insufficiency, but it is also possible to make the base thicker and reduce it to the target value by etching, lapping, grinding, etc. The mounting base has exactly the same dimensions. In addition, even if the base mounting part of the head base is cut to match the target dimension instead of the base surface, the dimension from the surface 8 of the head base 1 to the lower end of the gap 7 of the head chip 3 will be accurate to the target value. You can get what suits you.

In the above embodiment, the method of joining the base and head base is to form a groove on the joint surface of the base and use adhesive in the groove. However, there are other ways to connect the base and head base. There are two methods for welding the contact part between the base and the head base, such as welding by passing electric current ff111 between them (Fig. 4) and welding the boundary between the base and the head base using a laser beam 12 (Fig. 5). Various methods are possible that do not change the spacing.

Effects of the Invention According to the present invention, it is possible to obtain a head in which the track height of the head chip on the head head matches the target value with high precision. The gap position of each head can be matched to the desired height with respect to the cylinder surface without adjustment, and the cylinder assembly process is also simplified. Also, when mounting multiple head chips on a piezoelectric bimorph element, there is no need for a complicated track height adjustment mechanism for each chip.
It becomes possible to mount a large number of heads within the limit of the driveable weight of the piezoelectric bimorph element.

[Brief explanation of drawings]

FIG. 1 is a perspective view of the head of the present invention, FIG. 2 is a front view of the head of FIG. 1 viewed from direction A, and FIGS. 3 to 5 are diagrams showing a method of manufacturing the head of the present invention. 1...Head base, 2...Base, 3
...Head chip, 4...Adhesive, 6
...Groove, 7...Gap bottom end, 8...
...Head base surface, 9...Measurement stand, l
O...Adhesive, 12...Laser beam.

Claims (6)

[Claims] (1) A magnetic head comprising a base to which a head chip is adhered, and a head mounting substrate (head base) to which the base is joined with at least a portion in contact without an adhesive. . (2) The magnetic head according to claim (1), wherein a recess for an adhesive reservoir is formed on the head-base joint surface of the base to which the head chip is joined. (3) After bonding the head chip to the base, measure the dimension from the head base joint surface of the base to the end of the gap of the head chip, adjust the excess or deficiency with respect to the target dimension, and then A method of manufacturing a magnetic head, characterized in that the stand and the head base are joined together so that at least a portion of the head base is in contact with the stand without using an adhesive. (4) The method of manufacturing a magnetic head according to claim 3, wherein the base end face is cut by etching so that the dimension from the base end face to the gap end becomes a target dimension. (5) The method of manufacturing a magnetic head according to claim 3, wherein a nonmagnetic thin film is formed on the base end face so that the dimension from the base end face to the gap end is a target dimension. (6) The method for manufacturing a magnetic head according to claim (3), wherein the base attachment portion of the head base is cut down to a target dimension.