JPS632980Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a magnetic head used as an erasing head of a video tape recorder, etc., and in particular to a head body consisting of a front core, a back core, and a coil wound around the front core. This is a magnetic head of the type in which a back core arranged with a predetermined gap is inserted into a case, and by providing a guide groove in the case for inserting the front core and the back core, a predetermined gap between the two cores is provided. The present invention relates to a magnetic head that facilitates maintaining the gap between the head and the head.

The erase head of a video tape recorder, etc.
The head main body shown in Fig. 1 is shown in Fig. 2 A to F (A is a plan view, D is a front view, and C to H are cross sections from A to H in Fig. A, respectively, in the direction of the arrows. A magnetic head is used, which is inserted into a magnetic head. In other words, in both figures,
A coil bobbin 3 and a coil 4 wound around the coil bobbin 3 are disposed outside the front core 2 of the magnetic head body 1.
is installed. A back core 5 is attached to one end of the front core 2 with a predetermined gap t therebetween. A gap 12 is provided in the case 11, and grooves 13 are further provided in the wall surfaces on both sides of the gap 12. The magnetic head main body 1 is inserted into the gap 12 of the case 11, and the groove 13 and the front core 2 engage with each other, and the groove 13 acts as a guide, and the magnetic head 1 is inserted into the case 1.
1 in a predetermined position.

In this magnetic head, the dimension of the gap t mentioned above is required to be 0.2 mm in order for the magnetic head to have good electrical characteristics.

Conventionally, in order to maintain this gap t at 0.2 mm, when attaching the back core 5, a double-sided tape 21 was interposed between the mutually opposing surfaces of the front core 2 and the back core 5. However, in this conventional method, since there is no commercially available double-sided tape with a thickness of 0.2 mm, two commercially available double-sided tapes with a thickness of 0.1 mm are pasted together and the method shown in Figure 3 is used. I was making this adhesive tape. That is, in the figure, a Teflon tape 23 coated with an adhesive on only one side is pasted on a Bakelite plate 22 with the adhesive side adhered to the bake plate 22, and release paper is applied to both sides of the Teflon tape 23. 0.1 peeled off
Double-sided tape 21A with a thickness of mm is pasted together, the release paper is peeled off on one side, and the double-sided tape 21B with the release paper 24 still attached is pasted on one side, and this is cut with a cutter to approximately 1 mm width. (For clarity, the width and thickness dimensions are shown at different degrees of enlargement in the figure.)

In the conventional method described above, in addition to the work of pasting these two double-sided tapes together and cutting them into 1 mm widths, which requires manpower, the pasting tape 21 is peeled off from the Teflon tape 23, and the back core 5 and front It also requires a considerable amount of man-hours to attach it to the core 2, which has the disadvantage of increasing costs.

The object of the present invention is to improve the above-mentioned drawbacks of the conventional magnetic head, and to provide a magnetic head which can easily maintain the gap between the front core and the back core and is therefore inexpensive.

In the present invention, the position of the front core 2 with respect to the case 11 is regulated by the groove 13, and if the position of the back core 5 is regulated with respect to the case 11 by the same means, the relative position of the front core and the back core can be adjusted. This objective was achieved by providing a guide groove in the case 11 for inserting the front core and a guide groove for inserting the back core.

Embodiments of the present invention will be described below based on the drawings. FIG. 4 is a diagram showing the case of the magnetic head according to the present invention, in which A is a plan view, B is a cross-sectional view of Ro-Ro in FIG.
C is a cross-sectional view viewed in the direction of the arrow, and D is × in B.
It is an enlarged view of a part. In the same figure, case 11
A guide groove 13 for engaging the front core is provided in the side wall of the gap 12, and a groove 14 for engaging the back core is provided adjacent to the groove 13. The positions of the grooves 13 and 14 are adjusted so that the distance a (see Figure 2) between the side edges is 0.2 mm. When assembling the magnetic head shown in this example, the front core 2 is inserted into the case 11 while engaging with the groove 13, and the coil bobbin 3 and the coil 4 are inserted into the front core 2.
By inserting the front core 2 and the back core 5 while engaging with the groove 14, the gap between the front core 2 and the back core 5 can be maintained at 0.2 mm. Actually groove 13, front core 2, groove 1
4 and back core 5 each have a gap of about 0.05 mm on each side, so the gap between both cores is theoretically 0.2 mm to 0.4 mm, but this degree of difference will affect the electrical characteristics. It only changes by about % and does not pose a practical problem.

According to the present invention, as described above, the 0.2 mm thick double-sided tape, which was the cause of the high cost of magnetic heads in the past, is no longer necessary, and the man-hours for attaching the tape are no longer required, so the man-hours for assembling the magnetic head are greatly reduced. Moreover, it becomes possible to automate the assembly, which was previously impossible, and therefore it is possible to significantly reduce the cost of the magnetic head.

[Brief explanation of the drawing]

Figure 1 shows the main body of the magnetic head, Figure 2 shows the case, where A is a plan view, B is a front view, and C to H are cross sections from H to H in Figure A, respectively, in the direction of the arrows. The perspective view, Figure 3, is a diagram showing the manufacturing method of the conventionally used laminated double-sided tape, and Figure 4
The figures show the case of the magnetic head according to the present invention, in which A is a plan view, B is a cross-sectional view of Ro-Ro in figure A, viewed in the direction of the arrow, and C is a cross-section of H-HA in figure A, viewed in the direction of the arrow. Figure D is an enlarged view of the × part in Figure A. 1... Magnetic head body, 2... Front core, 3... Coil bobbin, 4... Coil, 5...
back core, 11... case, 12... void,
13...Groove, 14...Groove, 21...Double-sided tape.

Claims (1)

[Scope of utility model registration request] In a magnetic head for a tape recorder, the head body is composed of a front core, a back core, and a coil wound around the front core, and a predetermined gap is placed between the front core and the back core, and the head body is inserted into the case. A magnetic head characterized by having a groove for inserting a front core and a groove for inserting a back core.