JPS5880126A - Magnetic head - Google Patents

Abstract

PURPOSE:To ensure good sound qualities although the driving speed of a tape is lowered, by providing magnetic heads of different working gaps in parallel to each other via a spacer. CONSTITUTION:The 1st magnetic head 1 of a short gap length and the 2nd magnetic head 2 of a large gap length are formed by butting ferrite core half bodies 11 and 12 as well as 31 and 32 to each other and then winding coils 14 and 33. A spacer 5 has a multilayered structure of a shielding plate 51 and the 1st and 2nd nonmagnetic materials 52 and 53. The spaces 54 and 55 are formed to the materials 52 and 53 to store the coils 14 and 33, respectively. The track width 15 of the head 1 is set larger than the track width 34 of the head 3, and the full width 56 of the spacer 5 is equal to the sum of the track widths. Then the TV signals are recorded and reproduced by the head 1; while the audio signals accompanied by the TV signals are recorded and reproduced by the head 2. As a result, a sufficiently high relative speed is obtained for recording/reproducing of the sound signals although the tape driving speed is low.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a magnetic helad 1 in which two working gaps are arranged in parallel.
It is related to ζ.

In a general video tape recorder (VTR), a magnetic head (video head) for recording and reproducing video signals and a magnetic head for recording and reproducing audio signals are arranged independently, and the magnetic heads are arranged diagonally and longitudinally of the magnetic tape. Each track is shaped like this. In order to achieve this long edge time of the VTR, it is effective not only to reduce the size of the track of the video head, but also to reduce the feeding speed of the magnetic tape accordingly. However, as the feeding speed of the magnetic tape decreases, the transmission band of audio signals recorded in the longitudinal direction of the magnetic tape decreases (for example, the tape speed
(below 6 kHz at 2 cm/sec), resulting in a significant deterioration of sound quality.

The present invention is suitable for application to the VTR in order to provide V'l'R that maintains the relative speed to the magnetic tape to the same level as the video head and exhibits sufficient sound quality even when the tape speed is low F. This paper proposes a new magnetic head. That is, a first magnetic head whose working gap has a short gap length and a second magnetic head whose working gap has a long gap length are sandwiched between a predetermined spacer so that the working gaps of both magnetic heads form independent tracks. The present invention aims to provide magnetic heads arranged in parallel.

FIG. 1 shows one embodiment of the magnetic head of the present invention. 8 in the figure, (1) is the first magnetic head (31 is The second magnetic head +51 has a large operating gap length (for example, 16 to 20 μm) suitable for recording and reproducing information having a relatively small amount of information such as an audio signal accompanying the television signal. A spacer that fixes the magnetic head.

The first magnetic head (11 is made by abutting core halves α11I made of ferrite material with the predetermined gap length above, and winding the coil d4 around the winding window α3.The second magnetic head (11) 31 also has a half core st+gQ made of ferrite material butted against each other with the above-mentioned predetermined gear length apart, and a coil (to) is wound using a winding window which is not visible in the figure.Spacer +51 is the shield plate (511 and the first
It has a multi-structure with +Ii2 non-magnetic material@-, the first non-magnetic material is connected to the coil I of the first magnetic head, and the second non-magnetic material is connected to the second magnetic head (coil 31). The tape contact surfaces of the first and second magnetic healds 111 (31 and spacer +51) are formed flush with each other to ensure alignment with the magnetic tape. I try to take it.

In this embodiment, during the track of the first magnetic helad 11) -
is 20 μm, while the distance between the tracks of the second magnetic head (3) is set to 10 pm4, and the hit distance of the spacer 15) is calculated as the sum of the distance between these tracks, that is, 30P.
I am trying to set it to I11. As described later, this magnetic head is a two-head helical scan type VT.
This is because when applied to R, the recording locus of one magnetic head is interposed between the recording locus of the other magnetic head.

Figure 2 shows this magnetic head placed on the rotary plate of a VTR with an opening angle of 180 degrees, and a magnetic tape (6) wound around a cylinder that inserts the magnetic head at an angle of just over 180 degrees. This is a diagram showing the track pattern on a magnetic tape. In the figure, V+, ^1 and vt, at are the first . The second magnetism A2 is formed during the subsequent half-rotation of the other magnetic head and the half-rotation period after one rotation @1.
The second magnetic head shows a scanning locus according to (3I). (7) is a control track.

Since the width of the spacer is made to correspond to the sum of the working gaps in the track, this can be applied to a VTR to transmit the television signal to the first magnetic head as well. If the second magnetic head is clouded so as to record and reproduce the audio signal accompanying the television signal, a sufficient relative speed for recording and reproducing the audio signal can be obtained even if the transport speed of the magnetic tape is reduced. In addition, the scanning trajectory of the audio signal can be interposed between the scanning trajectory of the television signal, and the scanning trajectories can act as a so-called guard band on one signal, improving the use of magnetic tape. can be done.

[Brief explanation of the drawing]

Figure 's1 is a perspective view of one embodiment of the magnetic head of the present invention, and Figure 2 is a track pattern diagram of a magnetic tape. Explanation of main drawing numbers 11th...First magnetic head, (3)...Second magnetic head, (5th page...Spacer.

Claims (1)

[Claims] A) A first magnetic head whose working gap has a small gap length, and a gear whose working gap is small! The second magnetic field with a large knob length? Tsudo and the first. A magnetic head comprising: a spacer for fixing the second magnetic head so that the second magnetic head is lined up at a predetermined interval so that each working gap forms an independent track. 21. The magnetic head according to claim 2, wherein the distance is equal to the sum of the first and second magnetic heads in the track. (3) The spacer sandwiches the shield plate in the middle! It has a multilayer structure of IN 1 + a second non-magnetic material, and the first non-magnetic material facing the first magnetic head connects the coil of the first magnetic head, and the second non-magnetic material facing the second magnetic head A magnetic head according to claim 1, wherein the non-magnetic material has a space for accommodating each coil of the second magnetic head.