JPS6018809A - Magnetic head - Google Patents

Abstract

PURPOSE:To facilitate an easy calculation of the head position and at the same time to prevent the clogging between core chips and the breakage of these chips, by setting two core chips between a pair of reinforcing materials so that they are set side by side within a face. CONSTITUTION:A core chip 1 is produced by butting core halves 11 and 12 of a metallic magnetic member to each other. This chip 1 has a coil window 13 at its center part and an action gap 14 which prescribes the lower end. A tape abutting surface 15 is rounded, and two core chips 1 and 2 are put together with virtually no space. Then a magnetic material coated with a nonmagnetic material is provided between the counter faces of chips 1 and 2 to eliminate a space between both chips. The reinforcing materials 3 and 4 are made of glass and has a size that can support the chips 1 and 2 set in parallel to each other. The material 3 and 4 also contain two through holes 32 and 33 corresponding to coil windows 13 and 23 respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a magnetic head used in VTRs and the like.

(b) Conventional technology In a home-use helical scan VTR, one
Two heads mounted at positions 80 degrees apart alternately record video signals in units of feed/Il on tracks opened diagonally on the magnetic tape. A so-called azimuth recording method is adopted in which the track width is reduced in order to improve the areal density of recording, and at the same time, the two heads are provided with positive and negative azimuth angles in order to reduce the adverse effects of crosstalk. Furthermore, in order to improve the tracing rate in the special reproduction mode, a so-called double azimuth head has been proposed in which a third head is disposed adjacent to one head and matches the azimuth of the other head.

FIG. 1 shows a schematic diagram of a conventional double azimuth head. The two helad chips (Hl) (H2) are individually attached to the base (B) using a suitable adhesive. This base 03) is further mounted on the above-mentioned rotating body and constitutes one of the two heads. The positional relationship of each head chip (Hl) (H2) is shown in second section enlarged. As shown in Figure 3, the working gaps (Gl) and (G2), which have positive and negative azimuths, are aligned correctly, that is, the distance between both gaps (c, head height 1) and the tape contact surface are adjusted. The symmetry of the curved surface shape, the gap depth d), etc. must be very strictly defined. In addition to the poor handling properties due to the small size of the core chip, this only contributes to reducing production costs without impairing workability. Also, there is a gap (S) between the two core chips.
Therefore, magnetic powder etc. can be deposited within this gap,
If it reaches above the tape contact surface, it will cause space loss and cause deterioration of head characteristics.

(c) Purpose of the Invention The present invention has been developed in view of the above points, and has a new configuration that allows easy determination of the positions of two core chips and effectively prevents clogging between the core chips and damage to the core chips. The present invention aims to provide a magnetic head.

B) Structure of the Invention The present invention provides two core chips having different azimuth angles between L sets of reinforcing bodies so that the core chips are lined up in the plane of the reinforcing bodies, and are integrated by the reinforcing bodies. The present invention is characterized in that two types of core chips are arranged in a set of reinforcing bodies so that each working gap is arranged one behind the other in the direction of track extension. This is because the surface of one reinforcing body can be used to accurately align the two core chips, and because they are sandwiched between the other reinforcing body,
This means that it is possible to prevent the mutual positional relationship of the core chips from collapsing during operation and to ensure the mechanical strength of the core chips. Furthermore, by providing a spacer between the core chips or by omitting this spacer so that the core chips collide with each other, it is possible to eliminate gaps between the core chips. Incidentally, the distance between the working gaps between the two core chips is suitably a distance equivalent to one horizontal scanning period. This is because the core chips can be arranged adjacent to each other, and there is no need (or less) for guaranteeing the delay of electrical signals.

Figure 4 is a front view of the magnetic head of the present invention, Figure 5 is a plan view, and Figure 6 is an exploded perspective view. Moreover, FIG. 7 is a front view showing the state in which this magnetic head is attached to a base.

In each figure, fllf2] is the core chip, f3041
is a set of reinforcing bodies, (5) is a coil, and (6) is a base.

Since the core chips fl)f21 are common except that one has a positive azimuth angle and the other has a negative azimuth angle, the core chip (1) will be described below as a representative. The core chip (1) is a half core (11) formed by molding a metal magnetic material such as A7P magnetic alloy or Sendust.
12+, and has a coil window 03) passing through the center, and this coil window allows the lower f
It has an actuation gap (14) that defines @ (depth end). Further, the tape contacting surface side is processed with a so-called radius so as to align with the running tape.

The total thickness of this core chip fi+ (in Japan, the size corresponding to the track width is set to, for example, about 30 μm or 20 μm. Also, the azimuth angle is set to 6 to 7 degrees. In addition, there is a 5i02 film etc. on the working gap side. A non-magnetic spacer is attached, and the bonding force between the core halves is obtained by a bonding material (not shown) provided on the back gap side.

In this embodiment, the two core chips flf21 are brought into contact with each other with almost no space between them. Although both core chips are magnetically short-circuited, in the above-mentioned application, since the two core chips are used at the same time, there is virtually no problem. In order to prevent a short circuit between the two core chips, a magnetic material whose surface is coated with a non-magnetic material may be provided between the opposing surfaces of the two core chips. In this way, two core chips fi
+(210) By not providing a gap between the two, it is possible to prevent the harmful effects caused by the eyelids hK due to the equal pressure of the magnetic powder.

In this embodiment, the reinforcing body +31141 has the same shape. It is molded from glass, and its shape is similar to 2 above.
It has a surface area large enough to support two core chips (IH21 when they are arranged side by side), and the thickness 0υ is approximately 100 μm.In the center, there is a coil window (13) (corresponding to 23i) of core chip to(2). Two penetrating holes (
It has (to) (to). Since the tape contact surface (2) is molded together with the two core chips fll+21 after they are integrated, they have approximately the same rounded shape.

The plane (to) of this reinforcing body (3) relative to the core chip Fl)+2+ is used as a reference to determine the operating gap distance (c, head height 1), etc. of the core chip Fl)+21, so it is formed as smoothly as possible. ing. Then, two core chips fi++21 are placed side by side on this plane and bonded together with an adhesive (not shown).

Reinforcing body (3) As the material is intended to ensure the mechanical strength of the core chip FLLF2+, a non-magnetic material with good workability, that is, the above-mentioned glass, is suitable, but in order to improve the regeneration efficiency, the area around the operating gap Glass and other parts may be made of magnetic material (ferrite).

The coil /1/(51 is wound through the coil window of the core chip +11 and the above-mentioned through-hole function, and the terminal is arranged on the back side of the base through the through-hole (6) of the base (6) as shown in FIG. Connected to a terminal such as a printed wiring board.

The base (6) is a rotating body or rotating cylinder called the head disk of the VTR, and a two-head helical μ-scan VTR.
It is attached as one head that makes up the. and,
In special playback mode, the core chip that exhibits the same azimuth angle as the other head is operated to enable playback operation with a good trace rate. In addition, in Fig. 7, the line (γ
) is the core chip f seen through the transparent reinforcement (3)
l) Displaying the abutment surface of F2+. However, other perspective lines are omitted to avoid complication in the drawing.

(F) Effects of the Invention In the present invention, two core chips with different azimuths are arranged and mounted together between a set of reinforcing bodies, so the two core chips can be handled as one head, making it easier to attach the chips to the base. could be significantly improved. Further, since there is no space between the two core chips in which magnetic powder or the like is deposited, deterioration of magnetic properties over time can be suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration diagram of a conventional head, and FIGS. 2 and 3 are an enlarged plan view and a front view of the vicinity of the operating gap of this head. 4 is a front view of the magnetic head of the present invention, FIG. 5 is a plan view, FIG. 6 is an exploded perspective view, and FIG. 7 is a front view of the magnetic head attached to a base. Explanation of main drawing numbers +1) (21... Core chip, (3) (4)...1
Set of reinforcements. Figure 1 Figure 2 Figure 7 11 11 °□.

Claims (1)

[Claims] fi+ Two core chips having different azimuth angles are arranged side by side in the in-plane direction of a set of reinforcing bodies, and are held in a sandwich-inch manner by the set of reinforcing bodies. magnetic head. (2) The core chip is characterized in that each front gap has a positive and negative azimuth angle, and the interval between both front gaps is set to a distance equivalent to one horizontal scanning period (370 μm in VHS format). A magnetic head according to claim (1). (3) Each of the reinforcing bodies has two through holes corresponding to the coil windows of each of the core chips, and coils are attached to each of the core chips using the through holes penetrating the coil windows. A magnetic head according to claim f1, characterized in that: