JPH087845B2 - Magnetic head - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head, and more particularly, to a composite structure in which a plurality of magnetic heads for recording, reproducing or erasing information by connecting a magnetic core to a magnetic recording medium are slidably connected. Type magnetic head.

[Prior Art] FIG. 3 illustrates the structure of a composite head which is used in a VTR (video tape recorder) as a conventional magnetic head of this kind, and which combines an audio / control head and an audio erasing head. is there.

In FIG. 3, reference numeral 1 is a voice / control head,
In a VTR (not shown), a magnetic core 2 for recording / reproducing an audio signal on an audio track of a video tape, and a magnetic core 3 for recording / reproducing a control signal for head servo on a control track of a video tape.
have. The magnetic cores 2 and 3 are fitted and fixed to the case 4 of the voice / control head 1, and the respective tip surfaces having magnetic gaps are provided in the openings 4a and 4b formed on the tape sliding surface on the front surface of the case 4. Arranged to be exposed.

Further, in FIG. 3, reference numeral 5 is an audio erasing head, which has a magnetic core 6 for erasing a signal of an audio track of a video tape. The magnetic core 6 is held by a holder 7 formed of a mold, and the tip end surface having two magnetic gaps for erasing is exposed on the tape sliding surface in front of the holder 7.

Then, in the voice / control head 1 and the voice erasing head 5, after aligning the track positions of the magnetic cores 2 and 6, the screw 9 is inserted into the voice erasing head 5 and fastened to the voice / control head 1, and both heads 1 , 5 are bonded together by, for example, bonding.

[Problems to be Solved by the Invention] By the way, in such a composite head, both heads 1,
As a method of aligning the track positions of the magnetic cores 2 and 6 of 5, the conventional method is to position the tracks while observing each track position with a microscope or a monitor TV. However, at this time, since the track positions of the magnetic cores of the two heads are finely adjusted in a state where the azimuth angle of the magnetic gap of the magnetic cores is adjusted by one of the heads, the adjustment work is extremely difficult and takes a lot of man-hours. There is a problem that it causes an increase in manufacturing cost.

[Means for Solving the Problems] According to the present invention for solving the above-mentioned problems, according to the present invention, the first and second magnetic cores are aligned in the track position and are separated from each other in the medium sliding direction. A third magnetic core that is spaced apart from the first magnetic core in a direction perpendicular to the medium sliding direction, and the first, second, and third magnetic cores are fitted to each other and predetermined. And a holding member having first, second, and third openings for holding the first, second, and third openings, the holding member having the first, second, and third openings. Each of the openings has first and second sides that are parallel to and oppose each other in the medium sliding direction, and the fitted magnetic core is pressed against the second side. Are provided for each of the second sides, and the second side of each We adopted a structure that is placed inside the body sliding surface.

[Operation] According to such a structure, by fitting the first, second, and third magnetic cores into the first, second, and third openings of the holding member, The protrusions provided on the first side of each opening are pressed against the second side for accurate positioning, and the respective track positions are adjusted to have a predetermined positional relationship with each other. That is, the magnetic cores can be easily and accurately positioned through the holding members, and the track positions of the magnetic cores can be extremely easily aligned with each other, and the adjustment work for the alignment is unnecessary.

In addition, since the second side serving as a position reference with which the magnetic cores fitted in the respective openings are pressed against each other is an inner side in the medium sliding surface, in the direction perpendicular to the medium sliding direction, There is no position reference distance difference between the first and second magnetic cores, and the distance between the position references is greater between the first and third magnetic cores than in the case where one or both of them are pressed against the first side. Can be shortened. Therefore, the relative track position deviation between the magnetic cores in the medium sliding direction due to expansion and contraction of the holding member or the like depending on the temperature change can be reduced, and the track position accuracy can be improved.

[Examples] Hereinafter, details of examples of the present invention will be described.

1 (A) and 1 (B) are the VTRs described above as the present embodiment.
The structure of a composite head formed by combining a voice / control head and a voice erasing head is described below. In both figures, the same or corresponding parts as in FIG. 3 of the conventional example are designated by the same reference numerals, and the description of the same parts will be omitted.

In the composite head shown in FIGS. 1 (A) and 1 (B), a holding plate indicated by reference numeral 8 is provided as a structure relating to the present invention different from the conventional example, and by this holding plate 8, the magnetic cores 2, 3, 6 are Each of the magnetic cores 2, 3, and 6 is held and positioned so that the respective track positions have a predetermined positional relationship with each other.

As the holding plate 8, a non-magnetic material such as stainless steel or brass is used, and its shape and structure are as shown in FIGS. 2 (A) and (B). That is, the holding plate 8 is integrally formed from a non-magnetic plate material, and its main body 8a is formed in a substantially rectangular and curved arc shape. Rectangular openings 8b and 8c for holding each of the three are formed. Opening 8
A semicircular protrusion 8d is formed at the center of the upper edge of b, and the opening 8
A semicircular protrusion 8e is also formed in the central portion of the lower edge of c.

Further, as shown in FIG. 2 (A), an arm portion 8f bent in an L-shape is projectingly provided on the upper left side edge of the main body 8a of the holding plate 8 in FIG. 2 (B). A rectangular notch (opening) 8g for holding the magnetic core 6 made of ferrite or the like is formed in the portion 8f. Two small semicircular projections 8h are also formed on the upper edge of the cutout portion 8g.

Further, as shown in FIG. 2 (A), protrusions 8i, 8j bent in an L shape are provided on the upper and lower portions of the right side edge of the main body of the holding plate 8 in FIG. 2 (B). There is.

On the other hand, in the head of this embodiment, since the holding plate 8 is provided, as a structure different from the conventional example, the case 4 of the voice / control head 1 is formed in a rectangular rectangular tube shape so that the holding plate 8 can be just fitted. , Its front side is open. Further, in FIG. 1 (B) of the case 4, a notch portion 4a for fitting the arm portion 8a of the holding plate 8 is formed in the front upper portion of the left side plate. Although not shown, the right side plate of the case 4 has holes for inserting the projecting pieces 8i and 8j of the holding plate 8, respectively.

Although not shown, the holder 7 of the voice erasing head 5 is provided with a hole for inserting the tip end of the arm portion 8f and a groove for inserting the base end portion.

When assembling the composite head based on such a structure, first, the holding plate 8 is fitted into the case 4 of the voice / control head 1 as shown in FIG.
Insert the case into the hole (not shown) of the case 4,
The holding plate 8 is fixed to the case 4 by fitting 8f into the notch 4a of the case 4.

Next, the magnetic cores 2 and 3 are fitted into the case 4 together with the other head components, and the tip ends of the magnetic cores 2 and 3 are fitted into the openings 8b and 8c of the holding plate 8 to hold them, respectively. The cores 2 and 3 are fixed in the case 4 together with other components.

At this time, as shown in FIG. 1B, the tips of the magnetic cores 2 and 3 are pressed and positioned by the protrusions 8d and 8e, respectively, on the lower edge of the opening 8b and the upper edge of the opening 8c. .

Next, the arm portion 8f of the holding plate 8 incorporated in the voice / control head 1 is inserted and fitted into the holder 7 (non-magnetic) of the voice erasing head 5 as shown in FIGS. 1 (A) and (B). Then, the magnetic core 6 around which the coil 10 is wound is sandwiched between the notches 8g and held. The magnetic core 6 is pressed against the lower edge of the cutout portion 8g by each of the protrusions 8h and positioned. FIG. 1C shows the positional relationship between the magnetic core 6 and the arm portion 8f.

After that, the voice / control head 1 and the voice erasing head 5 are integrally joined by screwing or bonding to complete a composite head.

The tape sliding surfaces of both heads 1 and 5 may be molded and finished by grinding, either after the heads have been joined, or in the state of a single body before the joining.

As described above, according to the head of this embodiment, the magnetic cores 2, 3, 6 are positioned by the holding plate 8, and the track positions of the magnetic cores 2, 3, 6 are mutually predetermined positions. Aligned to have a relationship.

Therefore, the respective track positions of the magnetic cores 2, 3, 6 can be extremely easily aligned with each other via the holding plate 8, and the adjustment work for the alignment becomes unnecessary. Therefore, the number of steps for assembling the composite head can be reduced, and the manufacturing cost can be reduced.

Further, if the shape and size of the holding plate 8 are highly accurate, the track positions of the magnetic cores can be adjusted with high accuracy.

Of course, even when three or more magnetic heads are combined to form a composite head, the same effect can be obtained by using such a holding plate.

Further, it goes without saying that the shape and structure of the holding plate are not limited to the above.

[Effects of the Invention] As is apparent from the above description, according to the present invention, the first and second magnetic cores, which are aligned in the track position and are separated from each other in the medium sliding direction, and the medium sliding member. A third magnetic core, which is spaced apart from the first magnetic core in a direction perpendicular to the moving direction, and the first, second, and third magnetic cores are respectively fitted and held at predetermined positions. A holding member having first, second, and third openings for storing the composite magnetic head, wherein the first, second, and third openings of the holding member are respectively The first side has a first side and a second side which are parallel to the sliding direction of the medium and are opposed to each other. The first side has a protrusion for press-fitting the fitted magnetic core to the second side. And each of the second sides is inside the medium sliding surface with respect to each of the first sides. Since the structure that is arranged on the magnetic cores is adopted, the magnetic cores can be easily and accurately positioned through the holding members, and the track positions of the magnetic cores can be extremely easily aligned. It is not necessary and the number of assembling steps of the composite head can be reduced to reduce the manufacturing cost. Further, it is possible to obtain an excellent effect that the relative track position deviation between the magnetic cores in the direction perpendicular to the medium sliding direction due to the temperature change can be reduced and the track position accuracy can be improved.

[Brief description of drawings]

1 (A), (B), and (C) relate to an embodiment of the present invention, and FIGS. 1 (A) and 1 (B) are a cross-sectional plan view and a front view showing the structure of a composite head, respectively. FIG. 3C is a sectional view of the voice erasing head, FIGS. 2A and 2B are a top view and a front view showing the structure of the holding plate in FIGS. 1A and 1B, respectively. The figure is a front view showing the structure of a conventional composite head. 1 …… Voice / Control head 2,3,6 …… Magnetic core 4 …… Case 5 …… Voice erasing head 7 …… Holder, 8 …… Holding plate 10 …… Coil

Claims (1)

[Claims] 1. A first magnetic core and a second magnetic core which are aligned in a track position and are separated from each other in a medium sliding direction, and are separated from the first magnetic core in a direction perpendicular to the medium sliding direction. And a third magnetic core arranged in the same manner, and first, second, and third openings for fitting the first, second, and third magnetic cores to each other and holding them at predetermined positions. And a holding member that the holding member has, wherein the first, second, and third openings of the holding member are parallel to the medium sliding direction and face each other. A second side is provided, and the first side is provided with a protrusion for press-fitting the fitted magnetic core to the second side. A magnetic head arranged on the inner side of the medium sliding surface with respect to the first side.