JPS6350790B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a rotation control device, and particularly to a rotation control device suitable for controlling the rotation of a rotating recording medium such as a video disc recorder.

(Prior art) For example, in a recording/reproducing apparatus using a disk-shaped rotating recording medium such as a video disk recorder, the rotational speed and phase of the recording medium are adjusted to a reference signal, and the mechanical It may be necessary to match the position to the temporal position of the reference signal.

FIG. 1 is a block system diagram showing an example of a conventional rotation control device of this type.
is a motor that rotationally drives the rotating recording medium 2,
The pulse (MWP) representing the rotational speed and phase detected from the rotating recording medium 2 is amplified by the amplifier 3, and after being shaped into a predetermined waveform by the shaping circuit 4, a part of it is supplied to the speed control circuit 5. Here, for example, the signal is frequency-voltage converted and supplied as a speed control signal to an amplifier 6 for driving the motor.

On the other hand, tone wheel pulse (TWP) indicates the rotational position of the rotating recording medium taken out from motor 1.
is supplied to the vertical phase detection circuit 7, where the phase is compared with the VF signal of the vertical synchronizing signal frequency supplied from the reference signal generator (SSG) 8.

This tone wheel pulse is also supplied to a gate 9 for lock detection, and its phase is compared with the gated output signal of the shaping circuit 4 at the gate 10 using a vertical reference (VD) signal supplied from the SSG 8.

The _2H signal with a frequency twice the horizontal synchronization signal frequency from the SSG 8 is divided by the 1/2 frequency divider 11, and then
It is balanced-modulated by the above-mentioned VF signal in the balanced modulator 12 and supplied to the signal generator 13, where it is converted into a signal with a frequency approximately 6 Hz lower than the horizontal synchronizing signal frequency and supplied to the switching circuit 14. This switching circuit 14 is also supplied with an HD signal which is a reference horizontal synchronizing signal from the SSG 8.

The output of the switching circuit 14 is supplied to a horizontal phase detection circuit 15, where the phase is compared with the output of the shaping circuit 4, and the comparison output is supplied to a switching circuit 16.

The switching circuit 16 includes a vertical phase detection circuit 7.
The output of the vertical phase detection circuit 7 is supplied together with the output of the gate circuit 10 to a gate 17 for lock detection.

The output of the switching circuit 16 is supplied as a phase control signal to the motor driving amplifier 6 via the gain switching circuit 18, and together with the output of the speed control circuit 5 described above, controls the rotational phase and speed of the motor 1.

The switching circuit 14 is switched and controlled by the output of the gate 9 for lock detection, the switching circuit 16 is switched and controlled by the output of the gate 17 for lock detection, and the gain switching circuit 18 is controlled by the outputs of the gates 9 and 17. Gain can be switched.

The operation of the apparatus configured as described above is such that when rotation is started, the switching circuit 16 is switched to the state shown in the figure, and the output of the vertical phase detection circuit 7 is applied to the amplifier 6 as a phase control signal. Phase control is performed by the output of the vertical phase detection circuit 7, and the lock state of the phase control is detected by the lock detection gate 17. When the lock state is reached, the output of the gate 17 causes the switching circuit 16 to move in the opposite direction as shown in the figure. As a result, the output of the horizontal phase detection circuit 15 is supplied to the gain switching circuit 18, and phase control is performed using the output of the horizontal phase detection circuit 15.

At this time, since the switching circuit 14 is switched to the state shown in the figure, a signal with a frequency approximately 6 Hz lower than the horizontal synchronization signal frequency from the signal generator 13 is applied to the horizontal phase detection circuit 15, and this signal and the shaping circuit The phase of the signal from 4 is compared, and the rotation of the motor 1 is controlled according to the phase error. Therefore, the rotation speed of the motor 1 changes slightly,
When the time position of TWP and the time position of the VD signal gradually shift, and when the gate 9 detects that this shift has reached a predetermined value, the detection output causes the switching circuit 14 to switch in the opposite direction as shown in the figure. The horizontal phase detection circuit 15 is switched to the SSG state.
8 is supplied, and the rotational phase of the motor is controlled by the phase error obtained by comparing the phases of this HD signal and the signal from the shaping circuit 4.

As a result, the rotational speed and rotational phase of the rotating recording medium are synchronized with the HD signal from SSG8, and the mechanical position of the rotation is a predetermined one determined by the relative temporal position of the VD signal and TWP. becomes.

(Problem to be Solved by the Invention) In the above-mentioned conventional device, in order to control the mechanical position of the rotating medium, the rotation speed of the rotating medium is slightly lower than the horizontal synchronizing signal frequency. Since a frequency signal is used, the time required to reach final synchronization will vary depending on the difference in frequency between this signal and the frequency of the horizontal synchronization signal, which is the frequency reference. If this time is too long, synchronization will fail. There was a problem in that it took a long time to reach this point, and if it was too short, an erroneous difference would occur in synchronization detection.

Furthermore, since an analog method such as balanced modulation is used as a means for obtaining a signal with a frequency slightly lower than the horizontal synchronization signal frequency, there are also problems such as a large influence from the surrounding environment.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention aims to control the drive motor by using a phase difference between a rotational position pulse obtained from a drive motor that drives a rotating medium and an external reference signal. Provided is a rotation control device for controlling a rotation control system, characterized in that the rotation control system is provided with means for applying a disturbance to the rotation control system in order to match a fixed mechanical position of the rotating medium with a temporal position of a reference signal. It is something to do.

(Embodiment) FIG. 2 is a block system diagram showing the configuration of an embodiment of the rotation control device according to the present invention. In addition, in this figure, the same parts as in FIG. 1 are given the same reference numerals, and the explanation thereof will be omitted.

In this embodiment, after the rotating recording medium reaches a constant rotation, in order to match the mechanical position (phase) of the reference frequency and the rotation frequency, the rotation control system is configured to accelerate or decelerate according to the phase difference between them. By applying disturbances of positive and negative polarity, the phase synchronization position under speed control is sequentially shifted, and the mechanical position (phase) of rotation of the rotating medium is controlled to a predetermined value.

That is, the pulse (MWP) representing the rotational speed and phase detected from the rotating recording medium 2 is amplified by the amplifier 3, shaped into a predetermined waveform by the shaping circuit 4, and then a part of the pulse is supplied to the phase detection circuit 15. Here, the phase is compared with the _2H signal from the SSG 8, and the error signal is sent to the amplifier 6 for driving the motor as a phase control signal via the adder circuit 19, which will be described later.
is supplied to

On the other hand, tone wheel pulse (TWP) indicates the rotational position of the rotating recording medium taken out from motor 1.
is supplied to the gate 20, where the waveform shaping circuit 4
After being gated and waveform-shaped by a signal from
The phase is compared with the VD signal supplied by The output of this phase detection circuit 21 is the output of the disturbance generation control circuit 2.
2.

On the other hand, the _2H signal and VD signal from the SSG 8 are supplied to the gate 23, and a gate signal for controlling disturbance generation is generated. The gate signal generated at this gate 23 is supplied together with the signal from the gate 20 to a gate-in detection circuit 24, and the output of this gate-in detection circuit 24 is supplied to a disturbance generation control circuit 22.

A VD signal is also supplied to the disturbance generation control circuit 22.

The output of the disturbance generation control circuit 22 is supplied to the addition circuit 19, where it is added to the phase error signal from the phase detection circuit 15, and acts as a disturbance to the phase control system.

The operation of this device will be explained.

First, in the phase detection circuit 21, the gate 20
The phases of the TWP and VD signals that have been shaped are compared, and it is detected whether the rotational speed is within a certain range. When the rotational speed falls within a certain range, the disturbance generation control circuit 22 becomes operational.

In this state, the gate-in detection circuit 24 detects the temporal position of TWP with respect to the VD signal.

Until the time position of TWP reaches a predetermined position with respect to the time position of the VD signal, the disturbance generation control circuit 24 generates a kick pulse as a disturbance,
When the predetermined position is reached, the generation of kick pulses is stopped and the control system begins to perform normal phase control operations.

The disturbance generation control circuit 22 uses the outputs of the phase detection circuit 21 and the gate-in detection circuit 24 to control the kick pulse depending on whether the disturbance is generated in the positive or negative direction and the temporal position of the TWP and the temporal position of the VD signal. Determine the length of the cycle.

That is, by the output of the phase detection circuit 21,
To set the time position of TWP to a predetermined position, depending on whether it is faster to move in the lead or lag direction,
The direction of the kick is determined, and based on the output of the gate-in detection circuit 24, it is detected whether or not the temporal position of TWP is within a predetermined range.If it is outside the predetermined range, the kick cycle is shortened and movement is started. make it faster,
When it is within a predetermined range, the kick cycle is lengthened to ensure that the time position of TWP is at the predetermined position.

Further, it is determined whether or not the time position of TWP has reached a predetermined value based on the output of the gate-in detection circuit 24, and when the time position of TWP has reached the predetermined position, generation of the kick pulse is stopped.

By using such a device, even when the rotating medium of the rotation control device is replaced with a different rotating medium, the expected amount of disturbance can be made proportional to the amount of phase change that can be obtained. Performance can be met.

(Effects) Since the rotation control device according to the present invention has the configuration as described above, it is possible to eliminate all the drawbacks of the conventional devices described above and provide an excellent rotation control device.

[Brief explanation of drawings]

FIG. 1 is a block system diagram showing the configuration of an example of a conventional rotation control device, and FIG. 2 is a block system diagram showing the configuration of an embodiment of the rotation control device according to the present invention. 1...Motor, 2...Rotating recording medium, 3, 6...
... Amplifier, 4 ... Shaping circuit, 8 ... Standard signal generator (SSG), 15, 21 ... Phase detection circuit, 1
9... Addition circuit, 20, 23... Gate, 22...
...Disturbance generation control circuit, 24...Gate-in detection circuit.

Claims (1)

[Claims] 1. In a rotation control device that controls a drive motor based on a phase difference between a rotational position pulse obtained from a drive motor that drives a rotating medium and an external reference signal, 1. A rotation control device comprising means for applying a disturbance to a rotation control system in order to match the temporal position of a reference signal. 2. The means for applying the disturbance is configured to be able to variably set the amount and polarity of the disturbance depending on the difference between the temporal position of the reference signal and the mechanical position of the rotating medium. rotation control device.