JPS62248165A - Disk driving device - Google Patents

Abstract

PURPOSE:To prevent deforming of a head mark caused by the press-contacting of a video head on a disk from occurring by rotating the disk with a time interval by a means to control a disk driving circuit. CONSTITUTION:At the time of recording/reproducing, the disk 2 is rotated for one turn or more by means of a signal A, and at the time of ending the operation, a driving signal B of a very short width (t) between two pieces of which there is a time interval T is supplied to the driving circuit 6 from a timer 8. By the repeated supply of the driving signal B, the disk 2 rotates for a small angle theta during each time T, and the head 4a moves to a position 4b. The angle theta is approximately proportionate to the time (t). Since the intermittent driving of the disk 2 is executed by means of the signal B directly supplied to a driving circuit 6 from the timer 8 omitting a control circuit 7, the power consumption is made small. Also, by making the time (t) in a random-number-value by a random number generating circuit, the probability of the head 4 to pressure-contact the disk 2 at the same position as the original position when returning from one circular running around on one same track is made almost zero, causing no disk mark to happen. Furthermore, by adding a disk detection circuit and stopping a motor 1 when a disk is not loaded, the power consumption is made further smaller.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Field of Industrial Application The present invention relates to a disk drive device most suitable for a video disk drive device such as a methyl video camera or a methyl video player.

(2) Background of the Invention The disks used in still video cameras correspond to the film in still cameras used at home. In the case of a still camera, the film is stored in the camera until the number of shots that can be taken with the film is exhausted. This period varies depending on the user, but can range from several days to several months.

A similar situation occurs with still video cameras. That is, there may be a gap of several months between one photo shoot and the next.

Furthermore, since this disk for a still video camera is capable of recording audio and data, there is a possibility that it will be installed in a disk drive device of a still video player that performs these recordings.

In a disk drive device for a still video camera of this kind, especially a disk drive device for a magnetic disk, when sound is emitted for a long time with the video head in pressure contact with the disk, the following changes occur.

(a) Dropouts occur in recorded and reproduced images.

(b) The durability of the disc decreases.

(C) The durability of the video head decreases.

(d) Disk rotational unevenness increases.

In order to prevent "head marks" and shape changes that occur on the disk due to contact between the video head and the disk, the following operations have conventionally been performed.

When the disk starts rotating, the video head is retracted from the disk surface in order to speed up the start of rotation.

When the rotation of the disk approaches a steady rotational speed, the video head is brought into contact with the disk. At steady rotational speed (ie, during recording or playback), the video head slides against the disk with optimal pressure.

After the shooting or playback is finished, the video head returns to the position removed from the disk surface and returns to the state at the start of shooting, etc.

Similarly, in order to prevent "head marks" and deformation of the disc caused by contact between the video head and the disc, in devices without a video head evacuation mechanism, the disc is placed in pressure contact with the video head and the disc. When rotation has stopped, an LED or buzzer is also used to warn the user.

(3) Problems to be Solved by the Invention Although the above-mentioned device having the video head evacuation mechanism provides optimal conditions for the operation of the video head and disk, the mechanism and control become complicated and the device becomes expensive. There is a problem.

Additionally, devices that do not have a video head evacuation mechanism require a warning device, and even if a warning device is installed,
Because it is not linked to a mechanism for ejecting the disc or releasing the video head, there is a greater possibility of creating "head marks" on the disc.

(4) Means for Solving the Problems The present invention was made in view of the above points, and its purpose is to prevent "head marks" and shape changes that occur on the disc due to pressure contact between the video head and the disc. year,
To achieve this objective, a disk drive circuit for driving the disk and a control means for controlling the disk drive circuit are provided, and the control means is configured to rotate the disk at time intervals.

(5) Examples Hereinafter, the present invention will be explained based on the drawings.

FIG. 1 is a block diagram showing an embodiment of a disk drive device according to the present invention.

In FIG. 1, a chucking part 3 is directly connected to a motor shaft (not shown) of a spindle motor l, and a disk 2 is placed on this chucking part 3.

Drive power is supplied to the spindle motor from a drive circuit 6, and the rotation phase speed and drive stop of the drive circuit 6 are controlled by a control circuit 7 to perform recording and reproduction. Stopping the spindle motor l is controlled by a signal from the timer circuit 8.

Recording and reproduction of video signals to and from the disc 2 is performed using the disc 2.
This is done by a head 4 that abuts on the
The head transport mechanism 5 transports the disk 2 in the radial direction. This allows the head 4 to select any track on the disk 2.

The drive circuit 6 also receives a drive control signal B from the timer circuit 8.
is supplied. The control of the spindle motor 1 by this timer circuit 8 is performed 1r as shown in FIG.

That is, when recording and reproducing, the disk 2 is rotated one or more times depending on the signal. When the recording/reproducing operation is completed, the timer circuit 8 outputs Fri T '# for a predetermined period of time.
At 7, a drive signal B having a minute time width t is supplied to the drive circuit 6. This operation is repeated, and the disk 2 is rotated by a minute angle θ every predetermined time T. FIG. 3 shows this slight intermittent rotation, and as the disk 2 rotates counterclockwise, the head 4a shown in FIG. 3(a) rotates with the disk 2 as shown in FIG. 3(b). It moves to a position 4b, which is separated by an angle O from the position 4a, with the relative relationship . The moving angle θ is approximately proportional to the minute time t seen in the north.

The above-mentioned intermittent drive of the disk 2 is performed by the timer circuit 8.
The signal is directly supplied to the drive circuit 8 without passing through the control circuit 7.

Since this is performed using the v3 control signal B, the power consumption in this case is very small, and the power consumption due to intermittent driving can be suppressed to a very small amount.

Note that the timer circuit 8 uses a system controller that performs system control of the disk drive device during recording and reproduction and during non-recording and reproduction.

FIG. 4 is an arrow diagram showing another embodiment of the disk drive SJI loading according to the present invention. In the figure, the same components as in FIGS. 1 to 3 are given the same reference numerals, and explanations thereof will be omitted.

In FIG. 4, a random number value is supplied from a random number generation circuit 9 to a timer circuit 8, and the timer circuit 8 determines a minute time t (FIG. 2(b)) based on this random Fl value. This provides the following effects.

In the embodiment shown in FIG. 1, since the minute time t is constant, when the node 4 goes around the same track and returns to its original position, the disk 2 and the spatula ! There is a possibility that there will be pressure contact between the two. Therefore, "head marks" on the disk 2 due to pressure contact between the disk 2 and the head 4 may accumulate, and eventually become a large "head mark."

According to the embodiment shown in FIG. 4, the minute time t is generated as a random number by the random number generation circuit 9, so that even when the head 4 returns after making a full turn on the same track, it remains in the same position as before when the head 4 returns to the original position. The possibility of pressure contact with the head 4 is almost eliminated, and the possibility of "head marks" occurring on the disk 2 can be reduced to zero.

FIG. 5 is a block diagram showing another embodiment of the disk drive device according to the present invention. In the figure, the same components as in FIGS. 1 to 3 are given the same reference numerals, and explanations thereof will be omitted.

In FIG. 5, a disk detection circuit 10 is provided for detecting whether or not a disk 2 is loaded.

This disk detection circuit 10 may be constituted by a mechanical switch that engages with the disk 2, and its output is ANDed with the output of the timer circuit 8 by an AND gate it.

The output signal B of the computer 11 is supplied to the drive circuit 6 instead of the output of the timer circuit 8 shown in FIG.

This disk detection circuit 10 can prevent the spindle motor l from being driven intermittently and wasting power when the disk 2 is not mounted. It is also possible to connect the random number generation circuit 9 shown in FIG. 4 to the timer circuit 8 shown in FIG. 5.

Note that, as is common to the embodiments shown in FIGS. 1, 4, and 5, the disc l may still be attached even when the battery is removed from the still video camera. be.

In this case as well, it is desirable to use a backup battery or the like for driving a display means such as a liquid crystal as a power source so that intermittent driving is possible.

(6) Effects of the Invention As explained above, the present invention is provided with a control means for controlling the disk drive circuit, and is configured so that the control means rotates the disk at time intervals. With a simple and inexpensive structure, it is possible to prevent "head marks" and shape changes that occur on the disk due to pressure contact between the disks.

[Brief explanation of drawings]

Figure 1 shows a disc drive according to the present invention! A block diagram showing an embodiment of the JJ device, FIG. 2 is a waveform diagram explaining the operation of the circuit shown in FIG. 1, FIG. 3 is a front view explaining the operation of the circuit shown in FIG. 1, and FIG. 5 is a block diagram showing another embodiment of the disk drive device according to the present invention, and FIG. 5 is a block diagram showing another embodiment of the disk drive device according to the present invention. l...Spindle motor 2...Disk 4...Head 6...Drive circuit 8...Timer circuit 9...Random number generation circuit 10...Disk detection circuit Patent applicant Konishiroku Photo Industry Co., Ltd. Company agent Patent attorney Yama 1) Takeki Figure 1 Figure 2 (a) Figure M3 (a) (b) Figure 4 Figure 5

Claims (3)

[Claims] (1) A disk drive circuit for driving the disk,
A disk drive device comprising a control means for controlling the disk drive circuit, and the control means rotates the disk at time intervals. (2) Claim 1, further comprising a random number generation circuit, wherein the random number generation circuit determines the rotation time.
Disk drive device as described in section. (3) A disk detecting means for detecting the presence or absence of the disk is provided, and the disk is intermittent rotationally driven by the control means only when the presence of the disk is confirmed by the disk detecting means. A disk drive device according to claim 1.