JPH0395763A - Protecting device for recording medium in magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To notify that the of a recording medium is still loaded after a main power supply switch is turned OFF by discharging a charge, which is charged in a charge / discharge circuit, to an alarm and driving the alarm when the main power supply switch is turned OFF and a recording medium load detecting means detects the loading of the recording medium. CONSTITUTION:A recording medium load detecting means 31 is provided to detect that a recording medium 11 is loaded, and an alarm 35 is provided to notify that the alarm is outputted while loading the recording medium 11. Further, a control means 10 is provided to execute control so that when a main power supply switch 22 is turned ON, the charge / discharge circuit can be charged by the output of a power supply circuit and when the main power supply switch 22 is turned off and the recording medium load detecting means 31 detects that the recording medium 11 is still loaded, the electric charge charged in the charge / discharge circuit can be discharged to the alarm 35 and the alarm 35 can be driven. Thus, even when the supply of power is interrupted, it can be notified that the recording medium 11 is still loaded in a magnetic recording and reproducing device.

Description

[Detailed Description of the Invention] Summary of the Invention When the main power switch is on, commercial power is input;
The charging/discharging circuit is charged by the output of the power supply circuit that converts it to a predetermined voltage, and if the recording medium loading detection means detects loading of the recording medium when the main power switch is turned off, the charging/discharging circuit is charged. The electric charge contained in the alarm is discharged to the alarm to drive the alarm. This notifies you that a recording medium is loaded in the magnetic recording/playback device even when the main power switch is off, preventing deformation of the recording medium caused by the magnetic head being in contact with the recording medium for a long time. Helpful.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protection device for a magnetic recording medium such as a magnetic disk in a magnetic recording/reproducing apparatus.

In this specification, the term "magnetic recording/reproducing device" refers to a magnetic recording device that records on a recording medium, a magnetic recording medium reproducing device that reads and reproduces records on a magnetic recording medium, and a recording/reproducing device that is capable of both recording and reproducing. It includes.

Conventional technology and its problems A typical recording/playback device is a still image capture device that captures a still image of a subject using a solid-state electronic imaging device, then modulates the output still/video signal with FM and magnetically records it on a rotating magnetic disk.・Video cameras, still playback devices that play back still video signals from magnetic disks, still video cameras that have both recording and playback functions.
There are cameras etc.

In such a recording/reproducing device, recording a video signal on a magnetic disk or reading a video signal from a magnetic disk is performed by bringing the magnetic recording/reproducing head into close contact with the recording surface of the magnetic disk. This is done by pressing the magnetic disk so closely that it partially deforms. Magnetic disks have some elasticity and have the property of restoring to their original state even if slightly deformed, so there is no problem even if the magnetic head is pressed against the rotating magnetic disk during recording or playback. . However, if you apply a magnetic head to a certain spot while the rotation of the magnetic disk is stopped,2 If this condition continues for a long time (for example, from several hours to several days), the magnetic head will not be in contact with it. The deformation of the part becomes permanent and marks from the magnetic head are left on the magnetic disk.

To prevent such problems from occurring, when a magnetic disk is loaded in a magnetic recording/reproducing device, the LE
This is indicated by a symbol D or the like.

This allows the user to know that a magnetic disk is loaded in the device. Even if the secondary power switch is off, if the primary power switch (main power switch) is on and power is being supplied, the control device is backed up. The above display is possible, but cannot be displayed if the main power switch is turned off. Therefore, if the power supply is cut off from the outside, the user will not be notified that the magnetic disk is still loaded.

Summary of the Invention Purpose of the Invention This invention provides a magnetic recording/playback device that retains a recording medium loaded in it even when the power supply is cut off due to the main power switch being turned off or the outlet being unplugged. It is an object of the present invention to provide a protection device for a recording medium in a magnetic recording/reproducing device that can notify the presence of a recording medium in a magnetic recording/reproducing device.

Structure, operation, and effect of the invention A protection device for a recording medium in a magnetic recording/reproducing apparatus according to the present invention includes a power supply circuit that inputs commercial power, converts it to a predetermined voltage, and outputs the same, and a commercial power supply side of the power supply circuit. a main power switch provided on the main power switch, a charging/discharging circuit that is charged by the power obtained from the output side of the power supply circuit when the main power switch is on, and a recording medium loading detector that detects that a recording medium is loaded. means, an alarm for notifying that the recording medium is left loaded, and a means for charging the charging/discharging circuit with the output of the power supply circuit when the main power switch is on; If the recording medium loading detection means detects loading of a recording medium when the power switch is turned off, the electric charge stored in the charging/discharging circuit is discharged to the alarm to drive the alarm. The invention is characterized in that it is equipped with a control means for controlling.

According to this invention, even if the supply of power from the outside is cut off, such as by turning off the main power source, if a recording medium is loaded in the magnetic recording/reproducing device, the alarm is driven by the charging/discharging circuit. This allows the user to know that a recording medium is loaded in the magnetic recording/reproducing device.
By taking out the recording medium from inside the magnetic recording/reproducing apparatus, it is possible to prevent marks from being left on the recording medium due to the pressure of the magnetic head. Furthermore, even if a recording medium is loaded while the external power supply is cut off, the alarm is activated, so the user can know that the power is off.

An embodiment in which this invention is applied to a recording/playback device having both recording and playback functions will be described in detail below. It is also applicable to playback devices.

DESCRIPTION OF THE EMBODIMENTS FIG. 1 is a block diagram showing the electrical configuration of a recording/reproducing apparatus.

The operation of each part of the recording/reproducing apparatus and the overall operation are supervised by a control device 10. This control device 10 is a central processing unit, preferably a microprocessor (hereinafter referred to as CPU).
It consists of a memory that stores the program and necessary data, and an interface with peripheral elements, circuits, devices, etc.

A magnetic disk H on which a still video signal is recorded or reproduced is housed in a disk pack (not shown), and when this magnetic disk l1 is loaded into the main body of the device, a disk motor moves at its center. It is attached to a 4L spindle.

A magnetic recording/reproducing head 12 (two magnetic heads are provided in a frame recording capable device) is movable in the radial direction of the magnetic disk 11 so as to be in contact with the magnetic recording surface of the magnetic disk l1 installed. It is located. In addition, the magnetic material (
A phase detector 14 is provided close to the core of the magnetic disk 11 to detect the magnetic flux of the chucking permanent magnet leaking from the chucking permanent magnet (not shown) and generate one pulse PG for each rotation of the magnetic disk 11. ing.

A plurality of (for example, 50) tracks are provided concentrically on the magnetic disk H. A guard band is provided between adjacent tracks, for example, the width of the track is 60μ.
m, the width of the guard band is 40 μm, and the track pitch is 100 μm.

The 50 tracks on the magnetic disk 1l are numbered in order from the outer circumference to the inner circumference. L-No. Track numbers up to 50. is attached. Track No. l
The home position HP is located outside the track No. An end position EP is located inside 50.

The disk motor 41 is controlled at a constant rotation speed, for example, 3.80 Or. by a servo control circuit 42. p. IIl. Feedback control is performed to rotate at a constant speed. The servo control circuit 42 also starts and stops the motor 4l in response to commands from the control device 10. The detection pulse PG from the phase detector 14 is input to the control device IO. In this embodiment, the magnetic disk 1l is 3.60 Or. p. m. Since the magnetic head 12 rotates at a constant speed, one track of still video signals, that is, one field of FM modulated video signals, is recorded or reproduced by the magnetic head 12 every 1/60 seconds of one rotation.

The magnetic head l2 is. The transfer drive control device 43 supports the magnetic disk 1i so as to be movable in the radial direction and controls the transfer in the same direction. Transferring the magnetic head 12 from the outer circumferential side to the inner circumferential side of the magnetic disk 11 by the transfer drive control device 43 is called forward transfer, and the transfer in the opposite direction is called reverse transfer.

The control device {0 gives instructions to the device 43 regarding the direction and amount of movement of the magnetic head l2. The device 43 includes a step motor, which is rotated by a predetermined angle by being supplied with a predetermined number of drive pulses, and the magnetic head 12 is moved by a distance corresponding to the number of pulses. For example, by applying one pulse to the step motor, the magnetic head t2 is moved by 10 μm.

Since video signals are recorded or reproduced while the magnetic disk IT is being rotated, a regulating plate 13 is provided to maintain good contact between the magnetic head 12 and the magnetic disk 11 at all times.

The imaging optical system 50 provided in the recording/reproducing apparatus is... It is composed of an imaging lens system 51, an aperture 52, and an optical shutter 53 for forming a subject image. The aperture 52 is. The optical shutter 53 is controlled by the control device 10 based on the light reception signal level of a light receiving element (not shown) arranged in the optical path, and the optical shutter 53 is controlled by the control device 10 in response to pressing a shutter release button (not shown). controlled by

At the focal plane of the optical system 50, a solid-state electronic imaging device 54 consisting of a two-dimensional imaging cell array such as a CCD is arranged. The video data accumulated in this image pickup device 54 is serially converted to still images in synchronization with vertical and horizontal synchronization signals.
The video signal is read out as a video signal, and its luminance signal component and chroma signal component are subjected to FM modulation in a recording signal processing circuit 55, and these modulated signals are combined and applied to the magnetic head 12 via a switching and amplifying circuit 56. Switching and amplification circuit 5
Reference numeral 6 is for switching and amplifying the recording signal given to the magnetic head 12 and the read signal by the magnetic head 12 according to the recording mode and the reproduction mode.

A read signal from a predetermined track of the magnetic disk 1l by the magnetic head 12 is applied to an envelope detection circuit 57 and a reproduction signal processing circuit 58 via a switching and amplifying circuit 56.

The envelope detection circuit 57 detects the envelope of the read signal, converts it into a digital signal, and sends it to the control device 10.
give to The control device 1o performs track search processing and peak position detection processing using the input envelope detection signal. Track search processing is performed when a new magnetic disk l1 is loaded or when the magnetic disk 11 is replaced, and by moving the magnetic head l2 across all tracks of the magnetic disk i1, Recorded tracks and unrecorded tracks are discriminated and stored as a track map. The peak position detection process is performed in the reproduction mode, and involves detecting the peak position of the envelope of the recording signal in the designated track to be reproduced, and positioning the center of the magnetic head {2 there.

The reproduction signal processing circuit 58 processes the video signal read by the magnetic head {2, and outputs it as a still video signal in, for example, NTSC format. The still video signal output from circuit 58 is transmitted to a cathode ray tube display (C
The video signal recorded on the magnetic disk 1i is sent to an external color television system (not shown) equipped with a RT) and its control circuit, and the video signal recorded on the magnetic disk 1i is visually displayed on the CRT.

The control device 10 controls the rotation of the magnetic disk 11 described above,
In addition to controlling recording and playback of still/video signals, reading various switches. The operation of the device and the movement of the magnetic head 12 are controlled based on the read results.

The recording and reproducing apparatus includes a primary side main power switch 22 and a secondary side power switch 15. The main power switch 22 is a switch for controlling the supply of commercial power 20 to the recording/reproducing apparatus itself, and the power switch 15 is a switch for supplying drive current to each circuit of the recording/reproducing apparatus.

This recording/reproducing device receives power from a commercial power source 20. One terminal of a power input terminal (a plug inserted into an outlet) 21 connected to a commercial power source 20 is connected to one end of the primary winding of a transformer 24 via the main power switch 22 of the recording/reproducing device, and the other terminal is connected to the other end of the primary winding of the transformer 24 via the fuse 23. The transformer 24 has two secondary windings, and voltages induced in these windings are applied to regulators 25 and 27, respectively. If the outlet is connected to the commercial power source 20 and the main power switch 22 is turned on, the regulator 25. 27 outputs direct current of a predetermined voltage.

The output of regulator 27 is given to control device 1o and relay 30, which will be described later. By giving the output of the regulator 27 to the control device IO, this control device 10
is started and operates.

The power switch 15 is. It is connected between a pull-up resistor R5 connected to the output current voltage V of the regulator 27 and the ground, and the on/off state of this power switch {5 is given to the control device 10 as an L level or H level signal. It will be done.

On the other hand, the output terminal of the regulator 25 is connected to a power control switch 26. When the power switch 15 is turned on, the control device 1o turns on the power control switch 26 according to the control signal, so that the output voltage of the regulator 25 is applied to all the above-mentioned circuits of the recording/reproducing device via the switch 26. added to.

The recording/reproducing device includes a magnetic disk detection switch 31 that is turned on when the magnetic disk 11 is loaded. One terminal of this detection switch 3l is connected to a pull-up resistor R4 connected to the power supply voltage V and an input port of the control device IO via a reverse current prevention diode 37, and the other terminal is connected to a voltage V from the regulator 27. As long as is occurring, it is grounded via the relay 30 (
As will be described later, when the relay 30 is energized, it shorts contacts B and D). Therefore, when the magnetic disk 11 is not loaded, the detection switch 3
Since l is off, an H level signal is given to the control device lO. When a magnetic disk is loaded and the detection switch 3l is turned on, an L level signal is sent to the control device IO.
given to. As long as the control device 1O is operated by receiving operating power from the regulator 27, when the above L level signal is input, the control device 10 lights up the display device 16 (for example, a light emitting diode) to indicate that the magnetic disk 11 is loaded. Display.

When the main power switch 22 is turned off or the commercial power supply is disconnected from the commercial power supply 20, the relay 30 connects the magnetic disk 1 in the recording/reproducing device.
1 is loaded, the buzzer 35 is controlled to emit a warning sound.

Relay 30 has A and E terminals, and B, C, D, F
, G and NC contacts. A coil of a relay 30 is connected between the A terminal and the E terminal. The A terminal is connected to the output side of the regulator 27, and the E terminal is grounded. Also, a protection diode 36 is connected between the A and E terminals.
is provided. As long as the operating voltage V is generated from the regulator 27, the coil is energized and the relay 30 is energized.

A resistor Rl and a diode 32 are connected between the A terminal and the ground.
A series circuit consisting of a capacitor 33 and a capacitor 33 is connected. The B contact is connected to the other terminal of the detection switch 31 as described above. The C contact is connected to the node between the diode 32 and the capacitor 33. The D contact is grounded as described above.

The F contact is connected to one terminal of the detection switch 31. G contact is resistor R2, diode 34 and resistor R
3 to one terminal of the buzzer 35.

The other terminal of this buzzer 35 is grounded. Also N
The C contact is not connected to anything.

When the relay 30 is energized, contacts B and D are short-circuited, and contacts F and NC are short-circuited. Therefore, the other terminal of the detection switch 31 is grounded via contacts B and D, and the on/off state of the detection switch 31 is provided to the control device 10 as L and H level signals as described above.

Contact point C is in a floating state. For this reason, a charging current flows into the capacitor 33 from the output side of the regulator 27 via the terminal A, the resistor Rl, and the diode 32.
Capacitor 33 is charged.

Furthermore, since the contact G is also in a floating state, no current flows to the buzzer 35.

When the main power switch 22 is turned off or the outlet is unplugged, the recording/reproducing device is turned off from the commercial power supply 22.
When disconnected from the relay 30, the output voltage of the regulator 27 becomes zero and the relay 30 is demagnetized. At this time, the B contact and the C contact are connected, and the F contact and the G contact are connected. When the magnetic disk l1 is loaded, the magnetic disk detection switch 31 is on. Therefore, the charge stored in the capacitor 33 is discharged through the contacts C and B, the magnetic disk detection switch 31, the contacts F and G, the resistor R2, the diode 34, and the resistor R3, and the buzzer 35
Since current flows through the buzzer 35, the buzzer 35 issues a warning for a predetermined period of time. This allows the user to be informed that the magnetic disk l1 is loaded. Therefore, the user can take out the magnetic disk 1l from the apparatus as necessary, and it is possible to prevent the magnetic head 12 from leaving marks on the magnetic disk H. The time period for which the buzzer 35 generates the warning sound can be arbitrarily set depending on the capacitance of the capacitor 33 and the discharge time constant.

Even if the magnetic disk 1l is loaded when the commercial power supply is cut off to this magnetic recording apparatus, if the capacitor 33 is charged, the buzzer 35 will sound and a warning will be issued.

[Brief explanation of drawings]

The drawing is a circuit diagram showing an embodiment of the invention. DESCRIPTION OF SYMBOLS 10... Control device, l1... Magnetic disk, 20... Commercial power supply, 21... Input terminal, 22... Main power switch, 30... Relay 31... Magnetic disk detection switch, 35...buzzer or more

Claims (1)

[Claims] A power supply circuit that inputs commercial power, converts it to a predetermined voltage, and outputs it; a main power switch provided on the commercial power side of the power supply circuit; when the main power switch is on, A charging/discharging circuit that is charged by a power source obtained from the output side of the power supply circuit, a recording medium loading detection means that detects that a recording medium is loaded, and a notification that a recording medium is left loaded. and an alarm for charging and discharging the circuit by the output of the power supply circuit when the main power switch is on, and a recording medium loading detection means for recording when the main power switch is off. Recording in a magnetic recording/reproducing device, comprising: control means for controlling the charging/discharging circuit to discharge the charge stored in the charging/discharging circuit to the alarm to drive the alarm when loading of a medium is detected. Media protector.