JPH0216407Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a magnetic head suitable for VTR audio recording and playback.

Conventionally, this type of magnetic head has adopted a structure in which a head front portion, which forms the sliding surface of the magnetic tape, is fixed to the front opening of the case with an adhesive.

FIGS. 1 and 2 show an example of such a conventional magnetic head. In these figures, the head front section 1 is constructed by bonding a dummy block 5 made of non-magnetic ferrite or the like to the front end of a head core 3 around which a coil 2 is wound through a non-magnetic material 4 such as glass to form a magnetic tape sliding surface. It is fixed to the front opening of a metal case 6 made of permalloy or the like via an adhesive. In this case, the metal case 6 and the head front part 1 can be bonded together by applying adhesive around the head front part 1, or by applying adhesive to the inner wall of the case and then inserting the head front part 1 into the metal case 6. I was running it by inserting
Workability is poor as it has to be done manually,
This not only requires a lot of man-hours, but also has the disadvantage that the adhesive may adhere to parts of the inner wall of the case that are not related to adhesion, or may adhere to the hands of the worker.

Furthermore, if an attempt is made to make the front opening of the metal case 6 larger than the head front section 1 to facilitate the bonding work, a problem arises in which the head front section 1 is misaligned. The present invention eliminates the above disadvantages and securely fixes the head front by providing sufficient adhesive between the head front and the front opening of the metal case without impairing the positioning of the head front. The aim is to provide a magnetic head that can

Embodiments of the magnetic head according to the present invention will be described below with reference to the drawings.

In Fig. 3, a metal case 1 made of permalloy, etc.
The square front opening of 0 has positioning corners 1 at the four corners.
A step groove 12 is formed except for the part 1, and after inserting the head front part 1 into the metal case 10, epoxy is applied to the gap formed by the step groove 12 between the metal case 10 and the head front part 1. A resin adhesive 13 is applied and filled, and the metal case 10 is sealed.
The head front part 1 is fixed to. Thereafter, the head front portion 1, which serves as the magnetic tape sliding surface, is polished to a mirror-like surface. The structure of the head front section 1 itself is the same as the conventional case shown in FIGS. 1 and 2.

According to the above embodiment, the following effects can be achieved.

(1) After putting the head front part 1 into the metal case 10, apply adhesive from the front of the case to fill the gap between the head front part 1 and the metal case 10 created by the groove 12. Can be done. At this time, by forming step grooves 12 on the four sides of the square front opening excluding the corners, the head front section 1 can be fixed to the case 10 accurately and reliably without compromising the positioning of the head front section 1. can. Therefore, the adhesive application operation can be performed using a dispenser (automatic application machine), thereby reducing the number of man-hours and automating the work.

(2) If an epoxy resin adhesive is used as the adhesive 13 provided in the step groove 12, the adhesive 1
3 becomes sufficiently strong when solidified, so that the thickness of the metal case 10 can be reduced.

(3) Unless the machining allowance of the step groove 12 is made extremely large, there is no need to practically consider the reduction in the shielding effect of the metal case 10 against induced noise.

Although it is preferable that the machining allowance for the step grooves 12 be small, it is set to an appropriate value in view of the viscosity of the adhesive used and workability. Further, the head core may be grounded to the metal case at the same time by using a conductive adhesive. Furthermore, if a resin mixed with a high permeability magnetic material is used as an adhesive, it is possible to improve the shielding effect against induced noise.

As described above, according to the present invention, there is obtained a magnetic head capable of accurately and reliably fixing the head front part to the case without impairing the positioning of the head front part.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an example of a conventional magnetic head, FIG. 2 is an exploded view of the same, and FIG. 3 is a front view showing an embodiment of the magnetic head according to the present invention. 1...Head front part, 3...Head core,
5...Dummy block, 6, 10...Metal case, 11...Corner for positioning, 12...Step groove, 1
3...Adhesive.

Claims (1)

[Scope of utility model registration request] In a magnetic head in which a head front portion, which is a tape sliding surface with a dummy block integrated into a head core, is adhered to a rectangular front opening of a metal case, a gap is partially created between the head front portion and the metal case. The magnetic head is characterized in that step grooves are formed on four sides of the rectangular front opening of the metal case excluding the corners, and an adhesive is provided in the step grooves to adhere the head front portion to the metal case. Head.