JPS58182105A - Rotary head device - Google Patents

Abstract

PURPOSE:To record and reproduce a signal through a single rotary switch and to simplify structure by bringing plural heads fitted to a rotary cylinder and a preamplifier under the optical switching control under the controller of a fixed part. CONSTITUTION:The rotary cylinder 10 is provided with the plural magnetic heads 12a-12n, a switching circuit 11 incorporating the preamplifier which is not shown in a figure, photodetecting elements 15a-15n connected to the switching circuit 11, and the rotor 13R of a rotary transformer 13. The control circuit 14 having light emitting elements 16a-16n controls the switching circuit 11 optically without contacting and also controls a changeover switch 17. During recording, an input signal 20 is amplified at a part 18 and the switch 17 is connected to the R to input the signal by the rotary transformer 13; and the controller 14 places the rotary cylinder 10 in a recording state through photocouplers 16 and 15. During reproduction, the rotary cylinder 10 is placed in a reproduction state and the outputs of the heads 12 are passed through the rotary transformer 13, amplified at a part 19, and outputted from a terminal 21. Consequently, only one rotary transformer is used and the structure is simplified.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotary head device in a magnetic recording/reproducing device such as a video tape recorder, and particularly to a rotary head device for a magnetic recording/reproducing device such as a video tape recorder. It is an object of the present invention to provide a rotary head device that can be mounted.

In general, a rotating head device has a magnetic head mounted on a rotating cylinder, and the number of magnetic heads mounted on the rotating cylinder has increased in order to increase the number of functions such as high-speed search and long-time recording and playback in video tape recorders. It has increased. FIG. 1 shows a conventional rotary head device. In Fig. 1, 1 is a rotating cylinder, 2a, 2b...2n
are the magnetic heads 3a, 3 mounted on this rotating cylinder 1.
b...3n goes to the above magnetism・Nods 2a, 2b...
...Rotating transformer for signal transmission to 2n,
4 is a switching circuit including a preamplifier circuit; 6 is a regenerative amplification circuit;
6 is a recording amplification circuit, and 7 is a control circuit. In such a rotary head device, during recording, the switching circuit 4 including the preamplification circuit is set to the recording state by the control circuit 7, and the signal applied from the input terminal 8 and output from the recording amplification circuit 6 is Each magnetic head 2a passes through each of the rotating transformers 3a, 3b, . . . 3n.

2b...Added to 2n. On the other hand, during reproduction, the switching circuit 4 including the preamplifier circuit is set to the reproduction state by the control circuit 7, and each magnetic head 2a, 2b...
・The output of 2n is output from each rotating transformer 3a, 3b...
3n, is taken out from the rotating cylinder 1, passes through the switching circuit 4 including the front amplification circuit, and is transferred to the regeneration amplification circuit 5.
and is output to the output terminal 9.

However, in the above-mentioned rotary head device, each magnetic head 2 a * 2 b . . . mounted on a rotary cylinder.
...2n and each switching circuit 4. Recording width amplification circuit6. Each magnetic head 2 is used for signal transmission between external circuits such as a reproduction amplification circuit.
Rotating transformer 3 corresponding to a, 2b...-2n
a, 3b, . . . 3n are used, and as the number of magnetic heads increases, the number of rotary transformer circuits also increases, making the design extremely difficult.

The present invention solves these conventional deficiencies, and
A rotating cylinder is equipped with a large number of magnetic heads and a switching circuit including a preamplifier circuit, and this switching circuit is optically controlled by a control signal from a control circuit in accordance with recording and reproduction. The rotary cylinder is configured to be connected to external circuits such as a recording amplification circuit and a reproduction amplification circuit through a rotary transformer. This configuration has the advantage that the rotary transformer can be used for both recording and reproducing VC, and that a large number of magnetic heads can be mounted without increasing the number of rotary transformers.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The rotary head device of the present invention will be described below with reference to drawings of embodiments.

FIG. 2 shows an embodiment of the present invention. In FIG. 2, 1o is a rotating cylinder, which is equipped with a switching circuit 11 including a preamplifier circuit, and has a large number of magnetic heads 12a.
, 12t)...12n are installed. The rotary cylinder 10 is configured to transmit signals to and from an external circuit through a rotary transformer 13. 14 is a control circuit, 16B, 15b...16
fi is an optical sensor connected to the switching circuit 11, 16
a, 16b, . . . 16n are light emitters connected to the control circuit 14, 17 is a recording/reproduction changeover switch, 18 is a recording amplification circuit, and 19 is a reproduction amplification circuit.

In such a configuration, during recording, a control signal is sent from the control circuit 14 to the light emitter 16. It is sent to the rotary cylinder 10 via the optical sensor 16 and set to a recording state. Input terminal 20
The recording signal applied to the recording increase rlJ circuit 189 resale transformer 13. The signal is applied to the magnetic head 12 via the switching circuit 11. At this time, the control signal from the control circuit 14 is transmitted from the light emitters 16a, 16b...16n to the optical sensor 1s.
B, 15b...16n, and the switching circuit 11 is set to the recording state, so that a large number of magnetic heads 12a, 12b...12n correspond to the recording mode. selected. Further, the recording/reproducing switch 17 is switched to the recording R side by a control signal from the control circuit 14.

On the other hand, during playback, a control signal is sent from the control circuit 14 to the light emitter 16.
．． It is sent to the rotating cylinder 1o via the optical sensor 15 and set to the reproducing state. The output of the magnetic head 12 is amplified by each preamplifying circuit, then selected by the switching circuit 11, supplied to the reproduction amplifying circuit 19, and taken out to the output terminal 21. At this time, the control signal from the control track 14 is transmitted to the light emitter 16.
B, 16b...16n to optical sensor 15a
, 15b .

12b...12fi are selected to correspond to the recording mode. Further, the recording/reproducing switch 17 is switched to the reproduction P side by a control signal from the control circuit 14.

In this way, during recording, the recording signal is sent to the rotary cylinder 10 by the rotary transformer 13 and supplied to a predetermined magnetic head.
During playback, the voice power of a predetermined magnetic head 12 is amplified by a preamplifier circuit, and after the switching is selected, the rotary transformer 13 is optically controlled so that it is extracted from the rotary cylinder 1o. It can be configured with a circuit, and a large number of magnetic heads can be mounted on the rotary cylinder 10 without adding a rotary transformer.

Note that power for the circuit mounted on the rotating cylinder 1o is supplied by a slip ring or the like. Although slip rings are not suitable for signal transmission due to their quality, they can maintain sufficient quality for power supply.

As described in detail above, according to the present invention, a switching circuit including a preamplifier circuit is mounted on a rotary cylinder, and this switching circuit is optically controlled and selected according to recording or reproduction. With this structure, it is possible to add more magnetic heads without adding a rotary transformer, which has the advantage of providing a rotary head device with a simple structure and a multi-functionality.

[Brief explanation of the drawing]

・Fig.'R1 is a block diagram of a conventional rotary head device, and FIG. 2 is a block diagram showing an embodiment of the rotary head device of the present invention. 10... Rotating cylinder, 12... Magnetic head, 13... Rotating transformer, 11...
...Switching circuit including pre-amplifier circuit, 19... Reproduction amplification circuit, 18... Recording amplification circuit, 14...
... Control circuit, 15 ... Optical sensor, 16.
...Control signal emitter. Name of agent: Patent attorney Toshio Nakao and 1 other person11
11 Figure

Claims (1)

[Claims] The rotary cylinder is equipped with a switching circuit including a large number of magnetic nodes and a preamplifier circuit that is optically controlled and selectively switched by control signals from the control circuit. To the rotation, which is configured to perform signal transmission with external circuits such as "Increase 11" circuits.
Throat device.