JPH1079109A - Magnetic head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic head which eliminates deviation of the azimuth angle of a chip from the normal angle when mounting the magnetic head on a rotary cylinder. SOLUTION: This magnetic head is provided with a roughly U-shaped planar base 1 comprising a base part 5 and a pair of chip mounting parts 6 and 7 protruding forward from left and right points of the base part 5, a chip 2 for recording and reproduction bonded on the front end part of the chip mounting part 6, a chip 3 for erasing bonded on the front end part of the other chip mounting part 7 and a mounting hole 8 which is provided on the base part 5 to screw the magnetic head down on a rotary cylinder 11 and the mounting hole 8 is provided at a location behind a head gap part 4 of the chip 2 for recording or reproduction. As a result, even when the perimeter of the mounting hole of the magnetic head is deformed by the clamping of the a mounting screw, the root of the chip mounting part of the chip 2 for recording or reproduction is pressed on the head mounting part while being kept horizontally to get rid of any inclination of the chip mounting parts 6 and 7. This eliminates deviation of the azimuth angle of the chip 2 for recording or reproduction from the normal value thereby achieving a recoding or reproduction accurately.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head mounted on a rotary cylinder for a VTR.

[0002]

2. Description of the Related Art A VTR has been reduced in size and cost, and a magnetic head mounted on a rotary cylinder has also been reduced in size. A magnetic head having two or three or more chips bonded and mounted on one plate-shaped base has been proposed. It has increased.

The structure of a conventional magnetic head will be described below with reference to the drawings.

As shown in FIGS. 8 and 9, a conventional magnetic head on which two chips 2 and 3 are mounted is formed from two positions on the left and right of a base 15 of a plate-like base 14 having a substantially U-shaped planar shape. Chips 2 and 3 are bonded and mounted one by one on the front end of each of chip mounting portions 16 and 17 projecting forward, and the base 15 is brought into contact with the head mounting portion 9 of the rotary cylinder 11 on the base 15 and mounted with the mounting screws 10. Mounting hole 18 for the base 1
5 is provided at the center. As shown in FIG. 5, the head mounting portion 9 is a surface perpendicular to the rotation axis 13 of the rotation cylinder 11.

As shown in FIG. 7, the chip 2 has a head gap portion 4 between a pair of left and right cores 2a and 2b. It has an azimuth angle θ. The reason for providing the azimuth angle θ in this manner is that, as shown in FIG. 6, the magnetic recording pattern 20 of one unit signal on the recording tape 12 is recorded with the azimuth angle θ inclined with respect to the width direction of the track 19. To adapt to that. The azimuth angle θ is determined to a predetermined value according to the standard of the recording method, and must be strictly managed as described below.

Since the head gap 4 is elongated, when the chip is used for recording, reproducing or recording / reproducing, its azimuth angle θ needs to be managed with high precision. This is because if a signal on a recording tape recorded on a chip having a changed azimuth angle θ is to be reproduced on a chip having a regular azimuth angle θ, the phase of the signal near the upper end and the lower end of the head gap portion 4 is low. This is because the displacement increases, and the read output decreases. On the other hand, in the chip in which the azimuth angle θ has changed, the reproduction output of the signal of the recording tape recorded by the chip having the regular azimuth angle θ decreases for the same reason as described above.
That is, the compatibility of the recording tape with other devices of the same recording system is reduced.

[0007]

The plate-like base 14 of the magnetic head is a non-magnetic material, generally a brass material, and has a thin plate shape, so that its strength is not strong. However, since a high mounting accuracy is required, It is tightened relatively strongly with the mounting screw 10. In the conventional magnetic head, the plate-shaped base 1
5 is strongly tightened by the mounting screw 10 at the center in the left-right direction.
6 and 17 have a problem that the azimuth angle θ is deviated from a normal value by being inclined and deformed so that the outer side is lowered.

As described above, if the azimuth angle θ of the chip deviates from the normal value, as described above, there is a problem that the compatibility of the recording tape with other devices of the same recording system is reduced.

An object of the present invention is to solve such a problem.

[0010]

According to a first aspect of the present invention, there is provided a substantially U-shaped plate comprising a base and a pair of chip mounting portions projecting forward from right and left portions of the base. A base, a recording / reproducing chip adhered to the front end of one chip attaching portion, an erasing chip adhered to the front end of the other chip attaching portion, and a magnetic head provided on the base portion, which is screwed to the rotating cylinder with a magnetic head. A magnetic head provided with a mounting hole for mounting the recording and reproducing chip, the mounting hole being provided at a position behind a head gap portion of the recording / reproducing chip.

According to the first aspect, even if the periphery of the mounting hole of the magnetic head is deformed due to the tightening of the mounting screw, the root of the chip mounting portion of the recording / reproducing chip is pressed against the head mounting portion in a left-right balanced state. Therefore, the tip mounting portion does not tilt, and the azimuth angle of the recording / reproducing chip does not deviate from a normal value.

The chip mounting portion to which the erasing chip is adhered is tilted in the same manner as in the conventional example, and its azimuth angle deviates from a normal value. However, strict accuracy is not required for the azimuth angle of the erasing chip. There is no problem in practical use.

According to a second aspect of the present invention, there is provided a plate-like base comprising a base and a plurality of chip mounting portions projecting forward from a plurality of locations of the base, a plurality of chips bonded to the front end of each chip mounting portion, and In a magnetic head having a mounting hole provided on the base for screwing the magnetic head to a rotary cylinder, the mounting hole is provided at a position behind a head gap portion of each chip.

According to the second aspect of the present invention, even if the periphery of each mounting hole of the magnetic head is deformed by tightening of all the mounting screws, the azimuth angles of all the chips are regulated as in the operation of the first aspect. Does not deviate from the value of.

In the first or second aspect of the present invention, when the left and right positions of the center line of the mounting hole are located within a width defined by the left and right ends of the head gap portion of the chip, the accuracy of the azimuth angle is improved. Can be kept high.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings.

The magnetic head according to the first embodiment of the present invention comprises:
As shown in FIGS. 1 and 2, the plate-like base 1 has a U-shape in which a recording / reproducing chip 2 is mounted on one side and an erasing chip 3 is mounted on the other side. Is 6
mm, the length of the portion protruding forward of the chip mounting portions 6 and 7 is 3 mm, the width of the chip mounting portions 6 and 7 is 2.5 mm, the thickness is 0.7 mm, and the mounting hole has a diameter of 1.05 mm. Numeral 8 is provided on the base portion 5 at a position behind the head gap portion 4 of the recording / reproducing chip 2. The mounting hole 8 is provided such that the left and right positions of the center line C are located within a width W defined by the left and right ends P and Q of the head gap portion 4 of the recording and reproducing chip 2.

When this magnetic head is mounted on the head mounting portion 9 of the rotary cylinder 11, the shaft of an M1 mounting screw 10 is inserted into the mounting hole 8 and the head is tightened with a torque of 300 gfcm, as shown in FIG. And a recording / reproducing chip 2
Of the azimuth angle θ was almost zero.

In the conventional example, as shown in FIG. 9, when a mounting hole 18 is provided in the center of the base 15 of the plate-like base 14 in the left-right direction, the head gap portions 4, 4 of the two chips 2, 3 are formed. Tilted in opposite directions, and the azimuth angle of the recording / reproducing chip 2 deviated from the normal angle by 13.1 minutes.

In the erasing chip 3, a deviation of the azimuth angle θ by several tens of minutes does not pose a serious problem in practical use. As described above, focusing on the recording / reproducing chip 2 for which the azimuth angle θ is to be controlled with high precision, the simple configuration of optimizing the drilling position of the mounting hole 8 for mounting the magnetic head, A magnetic head in which the azimuth angle θ of the recording / reproducing chip 2 does not change when the magnetic head is attached can be realized.

The magnetic head according to the second embodiment of the present invention comprises:
As shown in FIG. 3, a magnetic head having a basic form similar to that of the first embodiment has a diameter of 1.05 mm.
The two mounting holes 26 and 27 are provided on the base 5 of the plate-like base 1 at the rear positions of the chips 2 and 3, respectively. The mounting positions of the mounting holes 26 and 27 are changed to the mounting holes 26 and 27.
The left and right positions of the respective center lines D and E are provided so as to be located within the width defined by the left and right ends P and Q of the head gap portions 4 of the chips 2 and 3. Rotating cylinder 1
As a result of being attached to 1, as shown in FIG.
The change in the azimuth angle θ of each of the three could be suppressed to almost zero.

In the above-described embodiment, the magnetic head to which two chips are bonded has been described. However, in addition to the above-mentioned recording / reproducing and erasing chips, chips for triple-speed recording / reproduction and still image reproduction are added. The above configuration can also be applied to a magnetic head in which three or more chips are bonded to the front ends of the corresponding chip mounting portions, and the same operation and effect can be obtained.

[0023]

According to the first aspect of the present invention, even if the area around the mounting hole of the magnetic head is deformed by tightening the mounting screw, the root of the chip mounting section of the recording / reproducing chip is left and right balanced in the head mounting section. The recording / reproducing chip can be accurately recorded because the chip mounting portion does not tilt and the azimuth angle of the recording / reproducing chip does not deviate from a regular value.

The chip mounting portion to which the erasing chip is adhered is inclined in the same manner as in the conventional example, and its azimuth angle deviates from a regular value, but strict accuracy is not required for the azimuth angle of the erasing chip. There is no problem in practical use.

According to the second aspect of the present invention, even when the periphery of each mounting hole of the magnetic head is deformed by tightening of all the mounting screws, the azimuth angles of all the chips are changed similarly to the operation of the first aspect. Since there is no deviation from the regular value, recording and reproduction can be performed with high accuracy.

In the first or second aspect of the present invention, if the left and right positions of the center line of the mounting hole are located within a width defined by the left and right ends of the head gap portion of the chip, the accuracy of the azimuth angle is reduced. Can be kept high.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment of the present invention.

FIG. 2 is an exemplary front view showing a mounting state of the magnetic head according to the first embodiment of the present invention;

FIG. 3 is a perspective view showing a second embodiment of the present invention.

FIG. 4 is an exemplary front view showing a magnetic head according to a second embodiment of the present invention;

FIG. 5 is a schematic perspective view showing a state in which a magnetic head is attached to a rotary cylinder.

FIG. 6 is a schematic diagram illustrating an azimuth angle of a magnetic recording pattern on a recording tape.

7A and 7B are enlarged views showing the structure of the chip, wherein FIG. 7A is a front view and FIG. 7B is a plan view.

FIG. 8 is a perspective view showing a conventional example.

FIG. 9 is a front view showing a mounting state of a magnetic head in a conventional example.

[Brief description of reference numerals]

 DESCRIPTION OF SYMBOLS 1 Plate-shaped base 2 Recording / reproducing chip 3 Erasing chip 4 Head gap part 5 Base part 6, 7 Chip mounting part 8, 26, 27 Mounting hole 11 Rotating cylinder C, D, E Center line of mounting hole P Head gap part Left end Q Right end of head gap

Claims (3)

[Claims] 1. A substantially U-shaped plate-like base comprising a base portion and a pair of chip mounting portions projecting forward from right and left portions of the base portion, and a recording / reproducing chip bonded to a front end of one of the chip mounting portions. An erasing chip bonded to the front end of the other chip mounting portion, and a magnetic head provided on the base portion for screwing the magnetic head to a rotary cylinder, A magnetic head, wherein the mounting hole is provided at a position behind a head gap. 2. A plate-like base comprising a base and a plurality of chip mounting portions protruding forward from a plurality of locations of the base, a plurality of chips bonded to the front end of each chip mounting portion, and a plurality of chips provided on the base. A magnetic head having mounting holes for screwing the magnetic head to a rotary cylinder, wherein the mounting holes are provided at positions rearward of a head gap portion of each chip. 3. The magnetic head according to claim 1, wherein the left and right positions of the center line of the mounting hole are located within a width defined by the left and right ends of the head gap portion of the chip.