JPS63266613A - Double azimuth magnetic head - Google Patents

Abstract

PURPOSE:To prevent the generation of damage of a magnetic tape and the disconnection and insulation fault of a coil by joining a non-magnetic insulting member with a hardness smaller than a core half body to the facing surface of a bar-shaped core half body with inorganic adhesives. CONSTITUTION:To the facing surface of bar-shaped core half bodies 2 and 8, glass plates 20 and 21, which are the non-magnetic insulating member of a thickness G0, are respectively joined with inorganic adhesives 4 and 9. The glass plates 20 and 21 are composed of the soft material with the hardness in which the Vickers hardness is smaller than the hardness of core materials 1, 7, 2 and 8 by about 100 or above. Thus, the generation of the damage of the magnetic tape and the dirt of the magnetic head due to the fact that the magnetic tape slides and connects to the sliding and connecting surface of the magnetic head can be prevented, the generation of the disconnection and the insulation fault of the wound coil can be prevented and the reliability of the magnetic head can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Purpose of the Invention (Industrial Application Field) The present invention relates to a magnetic head used in a magnetic recording/reproducing device such as a video tape recorder (hereinafter referred to as VTR), and particularly relates to a The present invention relates to a double azimuth magnetic head having a magnetic head.

(Prior Art) In recent years, as the density of magnetic tapes used in VTRs has been promoted, special playback functions such as high-speed playback and still image playback are also required as additional functions.

One method for satisfying these reproduction functions is a so-called double azimuth magnetic head.

This double azimuth magnetic head has conventionally been constructed as shown in FIG. In the figure, a winding groove 3 is formed in one core half 1 of core halves 1 and 2 whose core material is a ferrite-based magnetic material, for example, M, -Zo single crystal ferrite, and a winding groove 3 is formed in the other core half 2. are formed into a bar shape, and the core halves 1.degree.2 are joined with an inorganic adhesive, for example, a glass material 4, via a magnetic gap g1 to obtain a first head core. Similarly, a core half 7 in which a winding groove 6 is formed and a bar-shaped core half 8 are joined with a glass material 9 via a magnetic gap q2 to obtain a second head core 4. Once the head core is obtained in this way, the substrate 12 on which the slit 11 is formed
Bar-shaped core halves 2.8 face each other on both sides of the slit 11, and are fixed with an organic adhesive so that the distance between the magnetic gaps 01 and 02 is a predetermined length Gl. Coils 13 and 14 are wound around each head core through winding grooves 3 and 6, respectively. The double azimuth magnetic head constructed in this way was disclosed in Japanese Patent Application Laid-Open No. 80-133.
It is known from the publication No. 13.

According to the conventional double azimuth magnetic head configured as described above, when the magnetic tape 15 slides on the sliding surface of the magnetic head in the direction of arrow A as shown in FIG. A deflection of 16 occurs between .10 and .10. As a result, the magnetic surface of the magnetic tape 15 may be damaged by the edges on the opposite sides of the 5° river of both head cores, the edges themselves may be scratched, or dirt 17 may adhere to the sliding surfaces of the head cores. There were some problems. In order to solve this problem, conventionally a chamfered portion 1 as shown in FIG.
8°19 was formed at the edge portion with a predetermined dimension.

However, this chamfering process requires a lot of man-hours and has the disadvantage that dirt tends to adhere to the edge portions where the chamfered portions 18 and 19 intersect with the magnetic tape sliding surfaces of the head cores 5 and 10. Further, the general cross-section of each head core in the area indicated by the dashed line in FIG. 10 is as shown in FIG.
The lengths I, I2 in the advancing direction of 5 are the lengths El, E2 in the same direction of the core halves 1 and 7 in which the winding grooves 3 and 6 are formed, respectively.
In many cases, it is less than 1/4 of the winding coil 13.
There is also the problem that the diameter of the coil wound around the core halves 2 and 8 of the 14 core halves becomes smaller, and the insulation coating of the coil is torn at the edges of the core halves 2 and 8, respectively, making it easy to cause insulation failure and disconnection. Ta.

(Problems to be Solved by the Invention) The present invention solves the problem of mechanical chamfering of the opposing edges of the magnetic tape sliding surfaces of a pair of head cores, which has been a problem in conventional double azimuth magnetic heads. This solves the problem that it is not possible to sufficiently prevent the occurrence of dirt and damage to the magnetic tape due to dirt on the head core, and that wires are easily broken or insulation defects occur in the wound coil due to the size and shape of the head core. An object of the present invention is to provide an inexpensive and highly reliable double azimuth magnetic head that can sufficiently prevent damage to the magnetic head, and also prevent disconnection and poor insulation of the wound coil.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention connects a core half having a winding groove and a bar-shaped core half through a magnetic gap. A double azimuth magnetic head comprising a pair of head cores which are butted together and joined with an inorganic adhesive, and which are symmetrically fixed to a substrate with the bar-shaped core halves facing each other with a predetermined distance between them. , a non-magnetic insulating member having a hardness smaller than that of the bar-shaped core half is bonded to the opposing surface of the bar-shaped core half using an inorganic adhesive.

(Function) According to the above configuration, since a non-magnetic insulating member that is softer than the core material is provided at the edge portion of the magnetic tape sliding surface of the magnetic head, it becomes easy to measure the deflection and alignment of the magnetic tape. Damage to the magnetic tape and generation of dirt on the head core can be prevented. Further, since the coil wound around the bar-shaped core half also comes into contact with the edge of this non-magnetic insulating member, it is possible to prevent disconnection of the coil and occurrence of poor insulation.

(Embodiment) Hereinafter, an embodiment of the double azimuth magnetic head according to the present invention will be described with reference to the drawings.

FIG. 1 shows an embodiment of the present invention. In the figure, parts that are the same or equivalent to those of the conventional example shown in FIG. 9 are designated by the same reference numerals, and their explanation will be omitted. The feature of this embodiment is that the opposing surfaces of the bar-shaped core halves 2.8 have a thickness G. The glass plates 20 and 21, which are non-magnetic insulating members, are respectively bonded with an inorganic adhesive. This glass plate 20.21 is the core material 1.
It is made of a soft material with a hardness that is about 100 or more Vickers hardness smaller than 7.2.8. For example, if the hardness of the core material is 650, the hardness of the glass material is 55.
It is below 0. The other configurations are almost the same as the conventional example shown in FIG.

Next, a method of manufacturing the magnetic head according to this embodiment will be explained.

First, as shown in FIG. 2, the gap-opposing surfaces 1a and 2a of the substantially rectangular parallelepiped core half blocks 1 and 2 made of Mn-Zn single crystal ferrite are polished to a mirror finish by lapping or polishing, and one core half block 1 is finished. Only in this case, the winding groove 3 and the glass filling groove 22 are formed to have predetermined dimensions. Next, as shown in FIG. 3, S t 02 , Aj! are applied to the gap depth portions of the core half blocks 1 and 2. 203,
A gap holding film 23 made of Zr 02 or the like is formed to a predetermined thickness using a vacuum thin film forming technique. Next, the core half blocks 1 and 2 are butted against each other at the gap facing surfaces 1a and 2a, and the bonding glass material 4 is placed in the winding groove 3 and the glass filling groove 22, and they are sealed and bonded. As roughly shown in FIG. 4, the gap facing surface 2a of the core half block 2 in which the winding groove 3 is not formed
The opposite side surface is cut by machining to a specified dimension I3, and the cut surface is finished flat by lapping, polishing, etc.

Next, as shown in FIG. 5, a glass plate 20, which is a non-magnetic insulating material with a thickness Go and softer than the core material, is attached to the core half block 2.
The head core blocks are bonded to the sides with an inorganic adhesive to obtain mutual head core blocks. Next, as shown in FIG. 6, the magnetic tape sliding surfaces 5a of the head core blocks are finished into a curved surface with a predetermined radius of curvature using a cylindrical grinder or the like, and at the same time, the gap depth D is made to match the standard value. Additionally, if necessary, an outer winding groove 24 is machined in a predetermined shape and size at a position that aligns with the winding groove 3 on the side opposite to the side to which the glass plate 20 of the head core block is bonded. do. Then, as shown by the dashed line, the head core blocks are sliced at a predetermined pitch Ps and azimuth angle θ.

The thus obtained head cores and the head cores U, which were processed in the same way and whose gap azimuth angles are opposite to those of the head cores, were cut so that the distance between the gaps g1 and Q2 was 01, as shown in FIG. Next, it is bonded to the substrate 12 with the slit 11 formed therein using an organic adhesive. Roughly shown in FIG. 8, the magnetic tape sliding contact surfaces of a pair of head cores 5 and 10 are simultaneously lapped by sliding in the six directions of arrows using a wrapping tape 25 having the same stiffness as the magnetic tape to be used. As a result, the edges 20a, 21a of the glass plates 20, 21 are unevenly worn, allowing proper contact with the magnetic tape. Then, winding coils 13 and 14 are wound around the head cores 5 and 10, respectively, to complete a double azimuth magnetic head.

Next, the operation and effects of this embodiment will be explained. Glass plates 20 and 21, which are softer than the core material, are bonded to the opposing sides of the pair of head cores, so that even if the magnetic tape is bent in the central space between the head cores and the ears, the magnetic tape will not hold. will not be damaged.

Also head core 5. io is less likely to be soiled by sliding contact with the magnetic tape. Roughly small core half 2,8
The diameter of the coil 13.14 to be WH is the same as that of the glass plate 20.
21, and since the glass plates 20 and 21 are soft and insulating, it is possible to prevent the coils 13 and 14 from being cut off and from causing poor insulation.

[Effects of the Invention] As described above, according to the present invention, a nonmagnetic insulating member that is softer than the core material is bonded to the opposing side surfaces of a pair of head cores of a double azimuth magnetic head, so that the magnetic tape can be attached to the magnetic head. It is possible to prevent damage to the magnetic tape and dirt on the magnetic head due to sliding contact with the sliding contact surface, and it is also possible to prevent wire breakage and insulation defects in the wound coil, thereby improving the quality of the magnetic head. Reliability can be improved.

[Brief explanation of drawings]

FIG. 1 is a plan view showing an embodiment of the double azimuth magnetic head according to the present invention, FIGS. 2 to 8 are perspective views showing the manufacturing process of the magnetic head according to this embodiment, and FIGS.
The figure is a plan view showing a conventional double azimuth magnetic head, and FIG. 11 is a sectional view taken along the line B--B in FIG. 10. 1.2, 7.8... Core half 3.6... Winding groove 4.9... Glass material (inorganic adhesive), River... Head core 12... Substrate 20.21 ...Glass plate (non-magnetic insulating member) (Jl,
12...Magnetic gap agent Patent attorney Nori Chika Yudo Hiroha Uji Kohachi
Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9

Claims (1)

[Claims] A pair of head cores is formed by a core half having a winding groove and a bar-shaped core half abutting each other through a magnetic gap and bonded with an inorganic adhesive, and the bar-shaped core half are placed at a predetermined interval. A double azimuth magnetic head configured by facing each other and fixed to a substrate symmetrically through a bar-shaped core half, and an inorganic non-magnetic insulating member having a hardness smaller than that of the bar-shaped core half is provided on the opposing surface of the bar-shaped core half. A double azimuth magnetic head characterized by being joined with adhesive.