JPH03205654A - Information reproducing device - Google Patents

Abstract

PURPOSE:To prevent useless consumption of electric power by inhibiting driving of a recording medium with a driving mechanism irrespective of any operation of an operating means when a regenerative signal cannot be supplied to an external device in response to an output of a detecting circuit. CONSTITUTION:This device is provided with the detecting circuit 9 for detecting whether or not a regenerative signal from the recording medium 5 can be supplied via output terminals 11 and 12 to the external device and a control circuit 1 for inhibiting the driving of the recording medium 5 with the driving mechanism 4 irrespective of any operation of the operating means 2 when the regenerative signal cannot be supplied to the external device. Then, when a monitor device is changed to receive its input of a signal from other device in either case of the output terminals 11 and 12 are not connected or connected with, for instance, the external device such as the monitor device, etc., the recording medium 5 such as a disk, etc., is inhibited from being driven. By this method, useless consumption of the power and abrasion of the recording medium 5 are prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an information reproducing device such as a video floppy disk reproducing device.

[Conventional technology]

Images taken with an electronic still video camera are recorded on a video floppy disk. When this video floppy disk is loaded into the playback device and played back, recorded images are displayed on a monitor device such as a CRT connected to the playback device.

[Problem to be solved by the invention]

However, in conventional playback devices, even when a monitor device is not connected to the playback device, or even when the monitor device is connected to the playback device and the monitor device is switched to accept signals from other devices, the disc was played. As a result, not only is power consumed unnecessarily, but the reproducing head or disk is also worn out more than necessary.

This also applies when other recording devices are connected for dubbing. This invention was made in view of this situation, and it avoids unnecessary power consumption, playback heads, disks, etc. This prevents wear and tear. [Means for Solving the Problems] An information reproducing apparatus of the present invention includes: a drive mechanism that drives a recording medium when reproducing a recorded signal; an operating means that is operated when starting reproduction of the recording medium; an output terminal for outputting a reproduction signal reproduced from the recording medium to an external device;
A detection circuit detects whether or not a reproduction signal from a recording medium can be supplied to an external device from an output terminal. and a control circuit that prohibits the drive mechanism from driving the recording medium regardless of the operation.

[Effect]

In the information reproducing device with the above configuration, for example, if an external device such as a monitor device is not connected to the output terminal, or even if it is connected, the monitor device is switched to accept signal input from another device. If there is
Driving of a recording medium such as a disk is prohibited.

Therefore, unnecessary power consumption and wear of the recording medium are prevented.

〔Example〕

FIG. 1 is a block diagram showing the configuration of an embodiment of an information reproducing apparatus of the present invention.

In the figure, a control circuit 1 made of, for example, a microcomputer controls each circuit, means, etc. in response to the operation of an operating means 2 including buttons, switches, etc. Power circuit 3
supplies the necessary power to each circuit, means, etc. A drive mechanism 4 drives a video floppy disk 5 as a recording medium. Reproducing circuit 6 including a reproducing head (magnetic head), etc.
reproduces the information recorded on the disc 5.

The reproducing circuit 6 transmits the signal reproduced from the disk 5 to an amplifier 7,
It is designed to be outputted to output terminals 11 and 12 via a resistor 8. Output terminal l2 is grounded. Output terminal 1
A detection circuit 9 connected to the output terminal 1 detects whether a monitor device, which will be described later, is connected to the output terminal 11 in a state where it can supply a reproduction signal. The display 10 performs a predetermined display.

The above is the configuration of the playback device that plays back the disc 5.

Next, the configuration of the monitor device to which the playback signal output from the playback device is supplied will be explained.

Reference numerals 21 and 22 indicate input terminals of the monitor device, which are connected to output terminals 1 1 . 1 2 of the reproduction device and cords 3 1 .3 2. The input terminal 2l is connected to an amplifier 24 via a capacitor 23, and is also connected to a resistor 25 and an NPN
It is grounded via transistor 26. The input terminal 22 paired with the input terminal 21 is the output terminal 1 of the playback device.
Similarly to the output terminal 12 paired with 1, it is grounded. 2
7 is a switching state detection circuit, which is a switch of the monitor device (
(not shown) is detected, and the detection signal is transmitted to the NPN
It is supplied to the base of transistor 26. That is,
Although not shown, a plurality of sets of input terminals 21 and 22 are provided, and a selected one of them is detected by the switching state detection circuit 27. Next, the operation will be explained with reference to the flowchart shown in FIG.

In use, the output terminal 1 1.1 2 of the playback device and the input terminal 2 1.2 2 of the monitor device are connected by the cord 3 1.3 2. Also, the monitor device is turned on and
When a switch (not shown) is switched to accept a signal from the input terminal 21.22, the switching state detection circuit 27 detects this and outputs a high level signal, and the NPN}- transistor 26 turned on. As a result, the input terminal 21 is grounded via the resistor 25 and the NPN transistor 26.

On the other hand, on the playback device side, when a power switch (not shown) constituting the operating means 2 is turned on, the power supply circuit 3 supplies necessary power to each circuit, means, etc. Furthermore, when a playback switch (not shown) constituting the operating means 2 is turned on, the control circuit 1 controls the drive mechanism 4 to rotate the disk 5. Then, the information recorded on the disc 5 is reproduced by the reproduction circuit 6.

The signal reproduced from the disk 5 is sent to a reproduction circuit 6 and an amplifier 7.
, resistor 8, output terminal l1, cord 31, input terminal 21,
It is supplied to an amplifier 24 via a capacitor 23. The amplifier 24 amplifies the input signal and displays it on a CRT or the like via a predetermined circuit (both not shown).

The above is the operation under normal conditions. However, if a monitor device is not connected to output terminal 1 1.1 2, or even if it is connected, input terminal 2 1.2
The switch is changed to accept signals supplied to input terminals other than 2 (not shown), and even if a reproduced signal is output, it may not be possible to monitor it.

Therefore, the control circuit 1 executes processing as shown in FIG.

First, when the power of the playback device is turned on, it is determined whether the playback switch is turned on (steps Sl and S2).

When reproduction is instructed, reproduction is executed (S3). At this time, the control circuit 1 determines whether the monitor device is effectively connected to the output terminal 11 from the output of the detection circuit 9 (
S4).

This determination method will be described below.First, the output terminal 11.
If no monitor device is connected to 12, output terminal 1
1.12 becomes open. Furthermore, even if a monitor device is connected, if the monitor device is switched to accept signals from input terminals other than the input terminals 21 and 22, the output of the switching state detection circuit 27 will be at a low level.
NPN transistor 26 is turned off. Therefore, the output terminals 11.12 are also in the open state.

On the other hand, if the input terminals 21 and 22 are enabled, the output of the switching state detection circuit 27 becomes high level, and NPN}-
The transistor 26 turns on. As a result, the output terminal 11 is grounded via the cord 3, the input terminal 21, the resistor 25, and the NPN transistor 26.

Therefore, when input terminal 21 is enabled, output terminal 11
Since the voltage of the video signal outputted from the resistor 25 is divided by the resistor 25, its amplitude becomes small. On the other hand, input terminal 2
When l is not valid, the voltage is not divided by the resistor 25, so the amplitude of the video signal at the output terminal 11 is large (compared to when the input terminal 2l is valid).

The detection circuit 9 detects the amplitude level of the signal output from the output terminal 11, for example, the level of the horizontal synchronizing signal within the vertical blanking interval, and outputs a signal corresponding to the detection result to the control circuit l.

When the monitoring device is not activated, the control circuit 1 controls the drive mechanism 4.
and the reproducing circuit 6 to stop the reproducing operation (S6)
.

At this time, if necessary, it is possible to display on the display 10 that the monitor device is not enabled. This not only prompts the user to enable the monitor device, but also allows the user to know that the fact that playback does not start does not mean that the playback device is out of order.

If the monitoring device is active, the control circuit 1 controls the operating means 2
The playback operation is executed until a stop switch (not shown) constituting the playback is operated (S4).

When the stop switch is turned on during playback, control circuit 1
controls the drive mechanism 4 to stop driving the disk 5,
The playback operation is stopped (S5, S6).

FIG. 3 shows the configuration of another embodiment of the information reproducing apparatus of the present invention.

In this embodiment, the switching state detection circuit 27 and the NPN transistor 26 are not provided in the monitor device, and the input terminal 21 is directly grounded via the resistor 25.

In this embodiment, the state of the output terminal 11 of the reproduction device does not change depending on the switching state of the input terminal of the monitor device, so the detection circuit 9 cannot detect this. However, if the monitor device is the output terminal 1 of the playback device 1.1
2 can be detected. Therefore, as in the case of FIG. 1, when the monitor device is not connected, the reproduction operation can be prohibited.

In addition to the code 31.32 that supplies the playback signal, a similar operation can be performed by providing another code between the monitor device and the playback device that transmits information regarding the effectiveness of the monitor device. You can also do it. However, doing so not only complicates the configuration, but also requires such a configuration in advance, which limits the monitor devices that can be used. Therefore, it is preferable to use the above embodiment.

A detection circuit 9 for detecting the connection state of the monitor from the output of the amplifier 7 is configured as shown in FIG. 4, for example. The operation will be explained with reference to the timing chart of FIG.

The vertical synchronization signal detection circuit 4l detects a vertical synchronization signal from the reproduced video signal (FIG. 5(A)) inputted from the amplifier 7 via the resistor 8, and detects a low level detection signal (FIG. 5(A)) during the detection period. B)) will occur. Mono multi vibrator 42
is triggered by the falling edge of the detection signal output by the vertical synchronization signal detection circuit 41, and the high level signal (
Figure 5(C)) is output. This period is a predetermined period (maximum 15H to 18H) until the next luminance signal is generated.
Although H is the horizontal scanning period), it is preferable to set it to a shorter period in consideration of safety.

When this mono multivibrator 42 is outputting a high level signal, the analog switch 43 is turned on (
Figure 5(D)). As a result, the reproduced video signal output from the amplifier 7 is supplied to the base of the NPN transistor 49 via the analog switch 43 and the coupling capacitor 44. A voltage divided by resistors 45 and 46 is applied as a bias to the base of the NPN transistor 49, its collector is connected to a predetermined voltage source Vcc via a resistor 47, and its emitter is connected to ground via a resistor 48. has been done.

The emitter of the NPN transistor 49 generates an amplified output of the synchronizing signal during the vertical retrace period, thereby charging the capacitor 50. Resistor 51 and capacitor 5
The low-pass filter 2 removes the ripple component of this charging voltage and supplies it to the non-inverting input terminal of the comparator 53. A reference voltage generator 54 is connected to the inverting input terminal of the comparator 53.
A predetermined reference voltage output by is supplied. Comparator 5
3 compares both inputs and outputs the comparison result to the control circuit 1.

In FIG. 1, whether NPN transistor 26 is off or not, output terminal 11.
12 is not connected to input terminals 21 and 22. N
PN}-The level of the synchronizing signal supplied to all transistors 49 is high. Therefore, the voltage input to the non-inverting input terminal of the comparator 53 (FIG. 5(E)) is the reference voltage ■,
Become bigger. As a result, the comparator 53 outputs a signal (FIG. 5(G)) that is at a high level while the analog switch 43 is on and at a low level while it is off.

On the other hand, in FIG. 1 or 3, the output terminal 11 is connected to the resistor 25 or the resistor 25 and the NPN transistor 2.
6, the level of the reproduction synchronization signal becomes small, and the voltage at the non-inverting input terminal of the comparator 53 (the fifth
(F)) is smaller than the reference voltage v1. the result,
The output of the comparator 53 remains at a low level (see Figure 5 (H
)).

Therefore, the control circuit 1 determines whether or not the monitor is substantially connected to the output terminals 11 and 12 from the output of the comparator 53 during the vertical retrace period (the period in which the analog switch 43 is on). can be determined.

Alternatively, for example, an RS flip-flop (not shown) may be connected as a latch circuit after the comparator 53.
It may be reset at the start of reproduction, set by the output of the comparator 53, and monitored by the output of the RS flip-flop.

In the above description, the level of the synchronization signal during the vertical retrace period is compared with the reference voltage, but it is also theoretically possible to compare the level of the luminance signal. however,
In that case, the level of the luminance signal changes depending on the image, making it difficult to set the reference voltage. Therefore, it is preferable to detect the level of the synchronization signal as in the above embodiment.

Further, in the above description, the case where a monitor is connected as an external device to the information reproducing device is taken as an example, but the present invention can also be applied to the case where a recording device such as a dubbing device is connected. [Effects of the Invention] As described above, according to the information reproducing apparatus of the present invention, the validity of the external device is detected from the state of the output terminal that outputs the reproduction signal of the recording medium, and it is possible to detect whether the external device is not connected or not.
Alternatively, even if it is connected, if the signal output from the output terminal is not accepted, the playback operation of the recording medium is prohibited, resulting in unnecessary power consumption and wear and tear on the recording medium and playback head. 6.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the structure of an embodiment of the information reproducing device of the present invention, FIG. 2 is a flow chart explaining the operation of the embodiment of FIG. 1, and FIG. 3 is a block diagram showing the structure of an embodiment of the information reproducing device of the present invention FIG. 4 is a block diagram showing the configuration of another embodiment of the detection circuit. FIG. 5 is a timing chart explaining the operation of the embodiment of FIG. 4. 1... Control circuit 2... Operating means 3... Power supply circuit 4... Drive mechanism 5... Disc 6... Playback circuit 9... Detection circuit 10... Display 1 1. 1 2...Output terminal 21.22...Input terminal 27...Switching state detection circuit

Claims (1)

[Scope of Claims] A drive mechanism that drives a recording medium when reproducing a recorded signal; an operating means that is operated when starting reproduction of the recording medium; and a drive mechanism that drives a recording medium when reproducing a recorded signal; an output terminal for outputting to an external device; a detection circuit for detecting whether or not a reproduction signal from the recording medium can be supplied to the external device from the output terminal; An information reproducing apparatus comprising: a control circuit that prohibits the driving mechanism from driving the recording medium regardless of the operation of the operating means when a reproduction signal cannot be supplied to the external device.