JP2004357337A - Video and audio device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To continue an operational mode before a power failure without any operation by a user at the time of power recovery, and further to select a state at power recovery in accordance with a time period of the power failure. <P>SOLUTION: There are provided a power failure detecting circuit 15 for detecting the power failure, a power recovery detecting circuit 16 for detecting the power recovery from the power failure, and a timer circuit 17 for measuring a time interval from the initiation of the power failure to the power recovery. When the power recovery has been detected by the power recovery detecting circuit 16, if a time period of the power failure that has been measured by the timer circuit 17 is within a predetermined time period, a system controller 12 continues the operational mode before the power failure, and if the time period of the power failure exceeds the predetermined time period, the system controller 12 turns off the electric power source. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an audiovisual apparatus that controls an operation state at the time of a power failure recovery according to a power failure time, for example, a video tape recorder, a DVD (Digital Video Disk) recorder, a video-integrated television receiver, a liquid crystal television, and a plasma television. And the like.

  In a conventional video tape recorder or the like having a power backup function, a power failure occurs during execution of various operation modes such as a reproduction operation (PLAY), a recording operation (REC), a fast-forward operation (FF), and a rewind operation (REW). In this case, when the power is restored from the power failure (hereinafter, referred to as power restoration), the power is all turned off regardless of the operation mode before the power failure.

  Therefore, for example, when a power failure occurs during a playback operation of the video tape recorder, and the power is restored in about several seconds to several tens of seconds, the video tape recorder is turned off, so the user operates the power switch again, It was necessary to return the video tape recorder to the playback operation before the power failure by operating the playback switch (this is referred to as prior art 1).

On the other hand, the time from when the vehicle switch is turned off to when it is turned on is measured, and when the measured time is within a predetermined time which is equal to or longer than the time required for starting the engine, the specific information stored in the memory is determined. There has been proposed an in-vehicle audio device configured to maintain an operation state corresponding to a function (for example, see Patent Document 1). This in-vehicle audio device has a problem specific to in-vehicle use, that is, a so-called special function of the in-vehicle audio device (for example, a scan operation of a tuner) is canceled even though the listener does not intend when the engine is started. The state of the release solves a unique problem that the state is not restored unless a predetermined key input is performed even after the accessory power supply is turned on.
Japanese Utility Model Publication No. 63-181121

  In the above prior art 1, if a short power failure (including an instantaneous interruption) occurs during execution of various operation modes of the video tape recorder, the conventional video tape recorder continues the operation mode at the time of the power failure even if the power is restored. Therefore, there is a problem that a user who wishes to continue the reproduction operation, for example, the same as at the time of the power failure, has to operate the power switch and the reproduction switch again. In addition, when the power is turned off, if the user does not stay in front of the audiovisual device, there is another problem that power is wasted.

  On the other hand, in the above-mentioned Patent Document 1, in order to solve the above-mentioned problem peculiar to the in-vehicle audio equipment, when a vehicle switch is turned on within a predetermined time after being turned off, a specific function stored in a memory is stored. Although the present invention is configured to maintain the operating state corresponding to the above, the problem to be solved is completely different from that of the present invention, and the means of solution is also different. That is, there is no solution in Patent Literature 1 for eliminating waste of power.

  The present invention has been made in order to solve such a problem. A first object of the present invention is to perform an operation mode before a power failure without a user performing any operation at the time of power recovery. To provide an improved audiovisual device. A second object is to provide a video and audio device that selects a state at the time of power recovery according to the length of a power outage time.

  In order to solve the above problems, an audiovisual device according to the present invention is an audiovisual device having a power supply backup function, which includes a power failure detection circuit for detecting a power failure, a power recovery detection circuit for detecting recovery from a power failure, and a power recovery function. A timer circuit for measuring the time until power failure, and when power recovery is detected by the power recovery detection circuit, if the power failure time measured by the timer circuit is within a predetermined time, an operation before the power failure is performed. A mode is provided in which the mode is continued and a control circuit for turning off the power when the power failure time exceeds a certain time.

  An audiovisual apparatus according to the present invention is an audiovisual apparatus having a power supply backup function, in which a power failure detection circuit that detects a power failure, a power recovery detection circuit that detects a return from a power failure, and measures time from a power failure to a power recovery. When the power recovery is detected by the timer circuit and the power recovery detection circuit, if the power failure time measured by the timer circuit is within a predetermined time, the operation mode before the power failure is continuously performed, If the power outage time exceeds a certain time, a control circuit that turns off the power is provided, so it is considered that the user is still in front of the TV, so the power is restored within a certain time. In such a case, the operation mode before the power failure is continued when the power is restored, so that the user can save time and effort. In addition, when a certain time has elapsed, the user can determine that the user is no longer staying in front of the television, and thus turning off the power can save power.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic block diagram showing a basic circuit configuration of a helical scan video tape recorder which is an embodiment of the audiovisual apparatus of the present invention.

  In the figure, 1 is an antenna input terminal, 2 is a tuner circuit for selecting a desired channel from received broadcast waves, 3 is a video signal processing circuit, 4 is an audio signal processing circuit, and 6 is a video signal recorded on a magnetic tape 8. A recording / reproducing head having different azimuth angles for reproducing the recorded video signal, recording an audio signal on the magnetic tape 8 and reproducing the recorded audio signal, 9 an RF converter, 10 A receiver, 11 is a servo circuit, 12 is a system controller for controlling the operation of the entire video tape recorder, 13 is a memory circuit, 14 is a key input unit provided with a power switch and various mode switches. All of the conventional video tape recorders have a well-known circuit configuration, and a detailed description thereof will be omitted.

  In the video tape recorder of the present invention, in the above configuration, a power failure detection circuit 15 for detecting a power failure, a power recovery detection circuit 16 for detecting a recovery from the power failure, and a timer circuit 17 for measuring a time from the power failure to the power recovery. Although not shown, the power supply has a backup function.

  In addition, the system controller 12 controls various operation modes such as recording, reproduction, fast-forward, rewind, and the like. In addition, when the power recovery detection circuit 16 detects power recovery, the power failure time measured by the timer circuit 17 is set in advance. When the power failure is within a set time (for example, one minute), the operation mode before the power failure is continued, and when the power failure time exceeds the certain time, the power is turned off. Is supposed to do it.

  Note that the fixed time is set to a time at which the user is considered to stay in front of the television even if a power failure occurs, and is set to one minute in the present embodiment, but is not limited to this. Absent. Further, the fixed time needs to be determined in consideration of the balance with the backup time.

  According to the video tape recorder having the above configuration, the television signal of the channel input from the antenna input terminal 1 and selected by the tuner circuit 2 is separated into a video signal and an audio signal. The signal is input to the audio signal processing circuit 4. The video signal input to the video signal processing circuit 3 is detected, amplified, and the like, and then modulated into a signal that can be recorded on the magnetic tape 8. 8 on the predetermined recording tracks.

  The audio signal input to the audio signal processing circuit 4 is detected, amplified, and the like, and then modulated into a signal that can be recorded on a magnetic tape 8. 8 on the predetermined recording tracks. On the other hand, when reproducing the video signal recorded in this way, the video signal reproduced from the magnetic tape 8 by the video recording / reproducing head 6 is demodulated in the video signal processing circuit 3 and then passed through the RF converter 9. It is provided to a video input terminal of the receiver 10. The audio signal reproduced from the magnetic tape 8 by the audio recording / reproducing head 7 is demodulated in the audio signal processing circuit 4 and then supplied to the audio input terminal of the receiver 10 via the RF converter 9.

  Next, an operation in the event of a momentary interruption or a short power outage during such a reproducing operation will be described with reference to the flowchart shown in FIG. That is, when a power failure occurs during the above-described reproduction operation, the power failure detection circuit 15 detects the power failure and outputs a power failure detection signal to the system controller 12 (steps S1 and S2).

  The system controller 12 stores the current operation mode (reproduction operation in this example) in the memory circuit 13 based on the power failure detection signal (step S3). Further, the system controller 12 operates the timer circuit 17 based on the power failure detection signal, and counts up the time during the power failure, for example, in units of 0.5 seconds (step S4). In this state, when the power is supplied again (power recovery), the power recovery detection circuit 16 detects the power supply and outputs a power recovery detection signal to the system controller 12 (steps S5 and S6).

  The system controller 12 reads the count time (that is, the power failure time) from the timer circuit 17 based on the power recovery detection signal (step S7), resets the count value of the timer circuit 17 (step S8), Prepare for counting up when power failure occurs.

  Next, the system controller 12 compares the count time (power failure time) read from the timer circuit 17 with a predetermined time (for example, one minute) (step S9). As a result, when the power outage time is within the fixed time, the operation mode before the power outage is read from the memory circuit 13, and the reproduction operation is continuously performed according to the read out operation mode (step S10). That is, even if the user does not perform any operation at the time of power recovery, the operation mode before the power failure is continuously performed. If it is within a certain period of time, it is considered that the user is still in front of the television, so by continuing the operation mode before the power failure, the user does not need to operate the switch again. Things.

  On the other hand, if the power outage time exceeds a certain time, the power is turned off as in the conventional case (step S11). In other words, if the predetermined time has elapsed, it is possible to determine that the user is no longer in front of the television, so that the power is turned off.

  In the above embodiment, the operation mode at the time of power failure is stored in the memory circuit 13 and the operation mode stored in the memory circuit 13 is read at the time of power recovery, but the operation mode at the time of power failure is stored. Instead, the operation mode at the time of power failure may be recognized by determining the state of each mode switch (not shown) at the time of power recovery, and the operation mode may be continuously performed.

FIG. 1 is a schematic block diagram showing a basic circuit configuration of a helical scan video tape recorder which is an embodiment of the audiovisual apparatus of the present invention. 5 is a flowchart for explaining an operation when a momentary interruption or a short power failure occurs during a reproducing operation.

Explanation of reference numerals

12 System controller (control circuit)
13 Memory circuit 15 Power failure detection circuit 16 Power restoration detection circuit 17 Timer circuit

Claims (1)

In audiovisual equipment with a power backup function,
A power failure detection circuit for detecting a power failure,
A power recovery detection circuit that detects recovery from a power failure;
A timer circuit that measures the time from power failure to power recovery,
When the power recovery is detected by the power recovery detection circuit, if the power failure time measured by the timer circuit is within a predetermined time, the operation mode before the power failure is continuously performed, and the power failure time is fixed. A video / audio device comprising: a control circuit for turning off a power supply when a time is exceeded.