JPH0370841B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a recording/reproducing device using a rotating head such as a VTR, and particularly relates to a power supply supplied to the circuit when the circuit is mounted on a drum equipped with the rotating head. be.

Helical scan type VTR using a rotating head
It has been considered to improve various characteristics such as S/N by mounting active circuits such as a recording amplifier and a reproducing amplifier on a rotating drum equipped with a rotating head. In this case, it is necessary to supply power to a circuit provided in the drum. Power can be supplied by supplying alternating current from the outside via a rotary transformer and rectifying this alternating current with a rectifier circuit installed in the drum, or by supplying direct current via a slip ring, etc. is possible.

However, since the method using a rotary transformer is AC transmission, there are switching operations, etc.
Therefore, various noises are generated. Furthermore, since the method using a slip ring involves mechanical rotational contact, there are problems with longevity and reliability due to wear.

The present invention is intended to solve the above problems,
Embodiments of the present invention will be described below with reference to the drawings.

In the drawing, a rotating shaft 2 is inserted through the center of a fixed drum 1 and is rotatably supported by bearings 3 and 4. The fixed drum 1 is mounted and fixed on a support base 5. A coil 6 is wound inside the support base 5, and the coil 6 is wound on the lower part of the rotating shaft 2.
A magnet 7 is fixed opposite to. The coil 6 and magnet 7 constitute a motor 8, and the rotary shaft 2 is rotated by the motor 8. A support member 9 is fixed to the upper part of the rotating shaft 2, and a rotating drum 10 is fixed to the support member 9. Head chips 11 and 12 are attached to the lower surface of this drum 10, and a circuit section 13 is provided on the upper surface.
This circuit section 13 includes active circuits such as a recording amplifier and a reproducing amplifier, and a rectifier circuit.

An annular recess is formed in the fixed drum 1 around the rotating shaft 2 of the rotating member 10 . Further, from the support member 9 on the rotating member 10 side, a cylindrical leg portion 9a is formed to protrude within the annular recess. Therefore, the core 15 is provided on the inner peripheral surface of the leg portion 9a of the support member 9.
is fixed, and coils 16 and 17 are fixed to this core 15.
is wound. The coils 16 and 17 are connected to a recording amplifier and a reproducing amplifier of the circuit section 13 via Leet wires 21 and 22. Fixed drum 1
A core 18 is fixed to a portion facing the core 15, and coils 19 and 20 are wound around the core 18. These cores 15, 18 and coils 16, 17, 19, 20 constitute a rotary transformer 24. A coil 25 is fixed to the outer peripheral surface of the leg portion 9a, and a magnet 26 is fixed to a portion of the stationary drum 1 that faces the coil 25. This coil 25 and magnet 2
6 constitute a generator 27. The power generation output obtained from the coil 25 of the generator 27 is applied to the rectifier circuit of the circuit section 13 through the lead wire 23. In addition, the lead wire 21,
Suitably thin insertion holes are provided in the support member 9 and the drum 10 in order to insert the holes 22 and 23 therethrough.

According to the above configuration, when the coil 6 is energized and the motor 8 is driven, the rotating shaft 2 rotates. The support member 9, drum 10, core 15, coil 25, etc. rotate together with this rotating shaft 2.
As the coil 25 rotates, this coil 24 cuts the magnetic flux of the magnet 26,
As a result, an alternating current is generated in this coil 25. This alternating current is applied to the circuit section 13 via the lead wire 23, converted into direct current by the rectifier circuit, and then supplied as power to a recording amplifier, a reproducing amplifier, etc.

During recording, the recording signal is applied to the recording amplifier via the rotary transformer 24, amplified, and then applied to the heads 11 and 12 alternately.
During reproduction, the signals alternately reproduced by the heads 11 and 12 are amplified by the reproduction amplifier and then taken out to the outside via the rotary transformer 24.

Although the coil 25 and the magnet 26 may be provided at appropriate locations other than those shown in the drawings, the coil 25 is provided on the rotating portion, and the magnet 26 is provided on the fixed portion. Also, coil 25 and magnet 2
6 may be arranged facing each other in the vertical direction. Further, an electromagnet may be used instead of the magnet 26.

As described above, the present invention provides a rotary head type recording and reproducing device in which a circuit 13 is provided on a rotary member 10 provided with a rotary head. A recess is formed, and a cylindrical leg 9a is formed to protrude from the rotating member 10 into the annular recess.A coil 25 is provided on one surface of the leg 9a, and the coil 25 of the annular recess is provided. The coil 25 and the magnetizing means 26 constitute a generator 27, and the other surface of the leg portion 9a and the surface of the annular recess facing this surface. This relates to a rotary head type recording and reproducing device characterized in that a rotary transformer 24 connected to the circuit 13 is provided between the two and the output of the generator 27 is supplied to the circuit 13. .

Therefore, according to the present invention, the leg portion is provided on the rotating member side, and the rotary transformer and the generator are provided on the inner and outer circumferential surfaces of the leg portion, so that the area of the annular recess in the fixed drum can be effectively utilized. The height of the assembly can be made smaller than before, and furthermore, since the bearing can be built into the fixed drum, it can be made even lower. Further, by providing a coil on the rotating side, power can be easily supplied to a circuit provided in the drum. Further, since a magnet is provided on the fixed side, the magnetic field of this magnet becomes a static magnetic field to the outside of the drum, and no noise or the like is generated outside. Therefore, much better effects can be obtained compared to the method of transmitting AC using a rotary transformer. Furthermore, since there is no mechanical wear, it is highly reliable and easy to implement. Therefore, it becomes possible to mount a recording amplifier, a reproduction amplifier, etc. on the rotating drum, and various characteristics such as S/N of the apparatus can be improved.

[Brief explanation of drawings]

The drawing is a side sectional view of a drum portion of a VTR showing an embodiment of the present invention. In addition, in the symbols used in the drawings, 1...fixed drum, 10...rotating drum, 11, 12...
Head chip, 13... circuit section, 25... coil, 26... magnet, 27... generator.

Claims (1)

[Scope of Claims] 1. In a rotary head type recording/reproducing device in which a circuit is provided on a rotating member provided with a rotary head, the fixed member has an annular recess formed around the rotation axis of the rotary member, and A cylindrical leg is formed protruding from the rotating member into the annular recess, a coil is provided on one surface of the leg, and a magnetizing means is provided at a position facing the coil in the annular recess. The coil and the magnetizing means constitute a generator, and a rotary transformer connected to the circuit is provided between the other surface of the leg and the surface of the annular recess opposite to this surface. 1. A rotary head type recording/reproducing device, characterized in that a rotary head type recording/reproducing device is provided with a generator, and the generated output of the generator is supplied to the circuit.