JPH04318302A - Rotary head drum for magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To enable a power supply to a signal process circuit for magnetic head of a recording/reproducing amplifier, etc., and to improve a reliability by unnecessitating mechanical contacts and eliminating the generation of electrical noise. CONSTITUTION:This device is provided with a rotary transformer 56 for a power supply which is constituted of the fixing side 62 fixed at a drum fixing side 8 and the rotating side 64 fixed at a drum rotating side 10. The fixing side 62 of rotary transformer for power supply is connected to a power source, and also the power is supplied to a power receiving part of the recording/ reproducing amplifier 20 through the rotating side 64 of rotary transformer for power supply in accordance with the rotation of a rotary drum 34.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a rotating head drum used in a magnetic recording/reproducing device such as a digital audio tape recorder or a video tape recorder, and in particular, the present invention relates to a power supply to a signal processing circuit for a magnetic head on the rotating side of the drum. Regarding structure.

0002

2. Description of the Related Art FIG. 3 is a block diagram showing a recording/reproducing circuit of a two-head helical scan type video tape recorder as an example of a magnetic recording/reproducing device and a rotary head drum. It is a sectional view as a structure.

The connection between the recording/reproducing circuit 2 and the rotary head drum 4 will be explained with reference to FIG.

The recording/reproducing circuit 2 outputs a recording signal to be recorded on a magnetic tape via a magnetic head 6 in a rotary head drum 4 via an input/output section 2a, and also outputs a recording signal to be recorded on a magnetic tape via a magnetic head 6 in a rotary head drum 4. The reproduction signal of the magnetic tape reproduced in step 6 is input, and power is supplied and outputted from the power supply section 2b.

On the other hand, the rotary head drum 4 has a drum fixed side 8 and a drum rotating side 10.

[0006] The drum fixed side 8 is equipped with a signal rotary transformer 12.
The transformer 12 has a pair of fixed sides (consisting of a pair of primary coils of the transformer 12) 14, and a pair of power supply brushes 16. The drum rotation side 10 is connected to a pair of rotation sides of a signal rotation transformer 12 (the transformer 1
2 is composed of a pair of secondary coils. ) 18, a pair of recording/reproducing amplifiers 20 as signal processing circuits for magnetic heads, a pair of magnetic heads 6, and a pair of power supply slip rings 22.

The drum stationary side 10 also has a stationary drum, not shown in FIG. 3, and the drum rotating side 8 also has a rotating drum, not shown in FIG. As the rotating drum rotates, a recording signal to the magnetic head 6 or a reproduction signal from the magnetic head 6 is transmitted via the fixed side 14 and the rotating side 18 of the signal rotary transformer 12, and each signal is recorded. Playback amplifier 2
0 and is amplified by this recording/reproducing amplifier 20.
Power is supplied through the power supply brush 16 and the power supply slip ring 22.

The structure of the rotary head drum 4 will be explained with reference to FIG.

The rotating head drum 4 includes a fixed drum 24 as a drum fixed side 8, a fixed side 14 of a signal rotary transformer 12, a stator 28 of a drive motor 26 (consisting of a substrate 28a and a coil 28b), and a power supply brush 30. (consisting of a brush part 30a and a holding part 30b thereof), and an arm 32.

The rotating head drum 4 also has a rotating drum side 1.
0, the rotating drum 34, the rotating side 18 of the signal rotary transformer 12, the magnetic head 36 (consisting of a head section 36a and its substrate 36b), the recording/reproducing amplifier 20, the disk 40, the power supply slip ring 42 (contact ring 42
a and its substrate portion 42b. ), drive motor 26
The rotor 44 (consisting of a case 44a and a magnet 44b), a collar 46, and a rotating shaft 48 are provided.

On the drum fixed side 8, the fixed drum 24 has a double cylindrical shape, and a signal rotary transformer fixed side 14 is fixed on the inner side of the bottom surface thereof, and a drive motor stator 28 is attached to the downward protrusion of the fixed drum 24. is fixed and attached to the rotating shaft 48 via a bearing 50.

Further, on the drum rotation side 10, a disk 40 and a rotation drum 34 are attached to a rotation shaft 48, a signal rotary transformer rotation side 18 is fixed to the lower surface of the disk 40, and a signal rotary transformer rotation side 18 is fixed to the lower surface of the disk 40. The power supply slip ring 42 is fixed, and the rotating drum 34
A magnetic head 36 is attached to the lower surface of the periphery, and a recording/reproducing amplifier 20 is attached to the upper surface. As a result, the magnetic head 36 is mounted so as to face the outside through the gap 52 formed at the periphery of each of the fixed drum 24 and the rotating drum 34, and the magnetic tape running around the side surface of the rotating head drum 4 is exposed through the gap 52. Recording and reproduction of signals will be performed by the facing magnetic head 52.

In such a structure, the fixed drum 24
As the rotary drum 34 rotates opposite to the rotary drum 34, a recording signal to the magnetic head 36 or a reproduction signal from the magnetic head 36 is transmitted via the fixed side 14 and the rotating side 18 of the signal rotary transformer 12, and , each signal is recorded and played back by the amplifier 2.
It will be amplified at 0. This recording/playback amplifier 2
Power is supplied to the power receiving section 20a of No. 0 from the power supply brush 30 via the power supply slip ring 42.

[0014]

In the conventional rotating head drum 4 described above, power is supplied to the recording/reproducing amplifier 20 by the power supply brush 30 and the power receiving slip ring 42. As the power supply brush 30 slides on the power supply slip ring 42 as the power supply brush 34 rotates, the contact area becomes worn and the contact state becomes unstable and electrical noise is likely to occur. .

In order to suppress the generation of electrical noise, it has conventionally been necessary to use expensive noble metals as materials for the power supply brush 30 and the power supply slip ring 42. Such precious metals have the disadvantage that the manufacturing cost of the rotating head drum 4 is high, and even if precious metals are used, electrical noise cannot necessarily be suppressed depending on environmental resistance and service life. However, the reliability was not sufficient.

Therefore, in the present invention, since there is no mechanical contact and no electrical noise is generated, power can be supplied to a signal processing circuit for a magnetic head such as a recording/reproducing amplifier, and its reliability can be improved. The purpose is to do so.

[0017]

[Means for Solving the Problems] In order to achieve this object, the rotary head drum of the present invention has a rotary power supplying transformer, and the power supplying rotary transformer is fixed to the fixed side of the drum. It consists of a fixed side and a rotating side fixed to the drum rotating side, and the fixed side of the power supply rotating transformer is connected to a power source, and as the rotating drum rotates, the power supply is connected to the rotating side of the power feeding rotary transformer. Power is supplied to the magnetic head signal processing circuit through the magnetic head signal processing circuit.

[0018]

[Operation] According to the above structure, there is no mechanical contact between the fixed side and the rotating side of the power supply rotary transformer. therefore,
When the drum rotation side rotates, the power supplied from the fixed side of the power supply rotary transformer to the signal processing circuit via the power supply rotary transformer rotation side does not include electrical noise caused by mechanical contacts as in the conventional case.

[0019]

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing the recording and reproducing circuit of a two-head helical scan type video tape recorder as an example of a magnetic recording and reproducing device and a rotary head drum, and FIG. 2 shows the structure of the rotary head drum. 3 and 4 according to the conventional example, the same reference numerals are given to the parts and parts corresponding to those in FIG. 3 and FIG.

As will be explained with reference to FIG. 1, the rotary head drum 54 of this embodiment has a power supply rotary transformer 56 and a power rectifier circuit 58. A feature is that a power source 60 is supplied from the fixed side 8 to the drum rotating side 10, and the supplied power is rectified by a power rectifier circuit 58 and then supplied to the power receiving section 20a of the recording/reproducing amplifier 20.

This power supply rotating transformer 56 consists of a fixed side 62 composed of a primary coil of the transformer 56 and a rotating side 64 composed of a secondary coil. 62 is fixed to the drum fixed side 8 and connected to the power source 60, while the power feeding rotary transformer rotating side 64 is fixed to the drum rotating side 10. The power rectifier circuit 58 is connected and fixed between the rotating side 64 of the power supplying rotary transformer and the power supply receiving section 20a of the recording/reproducing amplifier 20, and rectifies alternating current induced in the rotating side 64 of the power supplying rotary transformer into direct current. Thereafter, the power is supplied to the power receiving section 20a of the recording/reproducing amplifier 20.

The structure of the rotary head drum 54 of this embodiment will be explained with reference to FIG.
In this case, the signal rotary transformer fixed side 14 and the power supply rotary transformer fixed side 62 are arranged side by side on the bottom surface of the fixed drum 24, and the disks are placed facing each other in a non-contact manner with a slight gap between them. On the lower surface of 40, there is a signal rotary transformer rotary side 18 and a power supply rotary transformer rotary side 6.
4 are arranged in parallel. Further, on the upper surface of the rotating drum 34, a power supply rectifying circuit 58 is arranged in parallel with the recording/reproducing amplifier 20. Note that the fixed side 62 of the power supply rotating transformer is shown in Figure 1.
The power supply rectifier circuit 58 is connected between the power supply rotary transformer rotation side 64 and the power supply receiving section 20a of the recording/reproducing amplifier 20. Their connections are as described with reference to FIG.

In this structure, the rotating drum 3
4 rotates, the power supply rotating transformer rotation side 64 has
AC power from the fixed side 62 of it is induced. This induced AC power is then converted into DC by the power rectifier circuit 58 and supplied to the power receiving section 20a of the recording/reproducing amplifier 20. Therefore, in the rotary head drum 54 of this embodiment, since the power feeding rotary transformer 56 itself for supplying power to the recording/reproducing amplifier 20 has no mechanical contacts, the power supplied to the recording/reproducing amplifier 20 is does not include the electrical noise that occurs in conventional mechanical contacts, and therefore the operational reliability of the recording/reproducing amplifier 20 is increased.

[0025]

[Effect of the invention] As is clear from the above explanation,
According to the present invention, a power feeding rotary transformer is provided, and this power feeding rotary transformer is configured with a fixed side fixed to a drum fixed side and a rotating side fixed to a drum rotating side, and the power feeding rotary The fixed side of the transformer is connected to a power source, and as the rotating drum rotates, the power source is supplied to the signal processing circuit for the magnetic head via the rotating side of the power feeding rotary transformer. In this case, since there is no mechanical contact between the fixed side and the rotating side of the power feeding rotary transformer, the drum rotating side rotates and the power is transferred from the fixed side of the power feeding rotary transformer to the rotating side of the power feeding rotary transformer. The power supplied to the signal processing circuit no longer contains electrical noise caused by mechanical contacts, which is the case in the past, and therefore the electrical noise no longer has an adverse effect on the operation of the signal processing circuit such as the recording/reproducing amplifier. As a result, its reliability can be improved.

[Brief explanation of the drawing]

FIG. 1 is a block wiring diagram of a recording/reproducing circuit of a two-head helical scan type video tape recorder and a rotating head drum according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the structure of the rotary head drum of FIG. 1;

FIG. 3 is a block wiring diagram of a recording/reproducing circuit of a two-head helical scan type video tape recorder and a rotary head drum according to a conventional example.

FIG. 4 is a cross-sectional view of the structure of the rotary head drum of FIG. 3;

[Explanation of symbols]

8 Drum fixed side 10 Drum rotating side 12 Signal rotating transformer 14 Signal rotating transformer fixed side 18 Signal rotating transformer rotating side 20 Recording/reproducing amplifier (signal processing circuit) 24 Fixed drum 34 Rotating drum 56 Power supply rotating transformer 58 Power rectification Circuit 60 AC power supply 62 Power supply rotating transformer fixed side 64 Power supply rotating transformer rotating side

Claims (1)

[Claims] [Claim 1] Drum fixed side (8) and drum rotating side (
10), and the drum fixed side (8) has a fixed drum (
24) and a signal rotary transformer fixed side (14),
The drum rotating side (10) includes a rotating drum (34), a rotating signal transformer rotating side (18), a magnetic head (36), and a signal processing circuit (20), and a fixed drum (24).
By rotating the rotating drum (34) facing away from the signal transformer, a recording signal is transmitted to or from the magnetic head (36) via the fixed side (14) and rotating side (18) of the signal rotating transformer. A rotary head drum for a magnetic recording/reproducing device having a structure in which a reproduction signal of 1 is transmitted and each signal is processed by a signal processing circuit (20), the rotary head drum having a structure in which a rotary transformer for power supply (20) is transmitted.
56), and the power supply rotating transformer (56) has a fixed side (62) fixed to the drum fixed side (8) and a rotating side (64) fixed to the drum rotating side (10). have,
The power supply rotating transformer fixed side (62) is connected to the power supply (60)
The power source (60) is connected to the rotating side (6) of the power supply rotating transformer (60) as the rotating drum (34) rotates.
4) A rotary head drum for a magnetic recording/reproducing device, characterized in that power is supplied to a signal processing circuit (20) via the rotary head drum.