JPH09312783A - Television receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the power consumption by interrupting power when no video signal is received and to automatically turn on power when the video signal is received. SOLUTION: A video signal processing circuit 1a of a video signal processing circuit 1 converts a received video signal into an RGB signal and provides an output of the signal to a CRT 5. Furthermore, a synchronization circuit 1b generates a horizontal drive signal and a vertical drive signal and they are fed respectively to a horizontal output circuit 3 and a vertical output circuit 4 to provide an output of a deflection current to a deflection yoke 10. On the other hand, the synchronization circuit 1b detects the presence of a synchronizing signal and gives the detection output to a microcomputer 2 as synchronization discrimination information. The microcomputer 2 discriminates the presence of a video signal when the synchronization discrimination information indicates presence of a synchronizing signal to leave switches SW1, SW2 closed, and the microcomputer 2 discriminates the absence of a video signal when the synchronization discrimination information indicates absence of a synchronizing signal to open the switches SW1, SW2 thereby interrupting the horizontal drive signal and the vertical drive signal and allowing the television receiver not to reproduce a video image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television receiver having a control circuit for turning on / off a power supply circuit of a television receiver, and more particularly to a television receiver capable of turning on / off the power supply circuit depending on the presence / absence of a video signal. It relates to a receiver.

[0002]

2. Description of the Related Art In a general television receiver, a power source can be turned on and off by a remote control device (hereinafter referred to as a remote controller). When power is supplied to the television receiver, the television receiver is turned on until it is turned off. Power continues to be supplied. In particular, it is good when receiving a broadcast television signal or while displaying an input signal from the outside, for example, a video signal from a VTR (video tape recorder) on a television receiver, but at midnight. For example, when the television signal from the broadcasting station is no longer broadcast, the video tape being played on the VTR is finished playing, or the video signal is recorded only halfway through the video tape. There is a problem that the television receiver continues to be supplied with power even when there is no television signal or video signal when the portion not being reproduced is being reproduced.

Therefore, the following techniques have been proposed to solve this problem. That is, when the television receiver is receiving the television signal, there is a synchronizing signal, so a circuit for determining the presence or absence of the synchronizing signal is provided in the synchronizing circuit of the video signal processing circuit of the television receiver.

Then, the output which determines the presence or absence of the synchronizing signal is supplied to a channel selection microcomputer (hereinafter referred to as a microcomputer) of the television receiver. This microcomputer is
It controls various television receivers and tunes, and can be turned on and off. When the power is turned off by the microcomputer, the main power supply for supplying power to each circuit can be cut off, but the power supply to the microcomputer is not cut off. Hereinafter, such a state is referred to as a standby state.

Therefore, the microcomputer determines from the presence / absence of the supplied sync signal whether or not the sync signal is present, determines that there is no television signal, and controls to turn off the power after a lapse of a predetermined time. Such a technique is disclosed, for example, in JP-A-63-60679 (H04N5 / 6).
3), JP-A-3-64282 (H04N5 / 6)
3), JP-A-4-140987 (H04N5 / 6)
Those shown in 3) have been proposed.

However, in these conventional techniques, when the television signal is lost and the power is turned off, the television receiver continues to maintain the standby state.
When the television vision signal is input again, the user must first release the standby state with the remote control, turn on the main power supply and supply power to each circuit before the television signal or video signal is transmitted. Cannot be played back on the receiver.

Particularly, when the television signal is temporarily interrupted during broadcasting and is re-broadcast, or when the reproduced video signal of the VTR includes a non-picture portion (a portion where no video signal is recorded), the non-picture In the above-described conventional technique, when the reproduction of a part is performed, the power is turned off when it is detected that there is no sync signal, so the user has to turn on the power again. In order to deal with such a situation, some improvement can be made by setting a certain period of time after the detection of the synchronization signal to be long, but not all of them can be dealt with.

When used for commercial purposes such as karaoke, since the television receiver is used as a monitor, the power source is normally kept on, so that the basic function of reproducing an image cannot be achieved. But it always consumes electricity. Although power consumption can be prevented even by using the above-mentioned conventional technique in the television receiver used for such an application, since the power is turned off when there is no synchronization signal,
When you use it, you have to avoid the hassle of having to turn on the power again.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and when the video signal is not input, the power is turned off to reduce the power consumption. It is an object of the present invention to provide a television receiver capable of automatically turning on the power when a signal is input.

[0010]

According to the present invention, there is provided a video signal input means for inputting a video signal, and a video output signal processing means for receiving a video signal from the video signal input means and supplying a video output to a cathode ray tube. Synchronous circuit means for extracting a sync signal of the video signal from the video signal input means and outputting a horizontal drive signal and a vertical drive signal from the sync signal, and for detecting the presence or absence of the video signal from the video signal input means Video signal detection means, deflection output means for supplying a horizontal output signal and a vertical output signal to the deflection yoke based on the horizontal drive signal and the vertical drive signal, and further for supplying a high voltage to the cathode ray tube, and the video signal detection means. And a control means for stopping the operation of the deflection output means in response to an output of the means for detecting the absence of a video signal. It is.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a flow chart showing the operation of a microcomputer.

In FIG. 1, reference numeral 1 is a video signal processing circuit, 1
a is a video signal processing circuit, 1b is a synchronizing circuit, 2 is a microcomputer for performing tuning and various controls of a television receiver, 3 is a horizontal output circuit, 4 is a vertical output circuit, 5 is a CRT (cathode ray tube), and 10 is The deflection yokes SW1 and SW2 are switches.

Next, the operation will be described. First, a television signal or a video signal is input to the television receiver from an antenna or an external input terminal (not shown) of the television receiver (the video signal is input for the following description). . Then, the video signal is input to the video signal processing circuit 1, decoded by the video signal processing circuit 1a into primary color (RGB) signals, and then input to the CRT 5.

On the other hand, the synchronizing circuit 1b separates the synchronizing signal from the video signal, supplies a horizontal drive signal based on the horizontal synchronizing signal to the horizontal output circuit 3, and vertically outputs a vertical drive signal based on the vertical synchronizing signal. It is supplied to the output circuit 4.

The horizontal output circuit 3 and the vertical output circuit 4 supply a horizontal deflection current and a vertical deflection current to the deflection yoke 10,
The deflection operation of the CRT 5 is performed. In addition, the horizontal output circuit 3
Generates a high voltage and supplies it to the anode terminal of the CRT 5.

By the way, the synchronizing circuit 1b is provided with a judging circuit for judging the presence or absence of a synchronizing signal. When a video signal is inputted, the synchronizing signal naturally has a synchronizing signal, so that the synchronizing judging circuit outputs synchronizing judgment information with the synchronizing signal. And supplies it to the microcomputer 2. Upon receiving the synchronization determination information, the microcomputer 2 outputs a switching control signal and switches SW1, S
Close W2. Then, the horizontal drive signal and the vertical drive signal from the synchronizing circuit 1b can be supplied to the horizontal output circuit 3 and the vertical output circuit 4. In this way,
Reproduction can be performed when the television receiver receives a video signal (the switches SW1 and SW2 are closed in the initial state when the power is turned on).

When there is no video signal, since there is no synchronizing signal, the switches SW1 and SW2 are opened and the horizontal drive signal and the vertical drive signal are not supplied to the horizontal output circuit 3 and the vertical output circuit 4, so that the deflection operation is performed. Since it is not performed, CRT2 cannot display anything. As a result, the horizontal output circuit 3 and the vertical output circuit 4 do not operate, and the power consumption can be reduced accordingly.

Next, the operation of the microcomputer 2 will be specifically described with reference to the flowchart of FIG. First, in the initial state, the switches SW1 and SW2 are closed. Therefore, when the main power of the television receiver is turned on (S1), the timer inside the microcomputer 2 is reset (S2). Then, it is detected whether or not the standby state is permitted, and if it is not permitted, the switch SW1,
The switch SW2 is kept closed (S10), and if permitted, the process proceeds to the next step (S3). Whether or not the standby state is permitted can be set by the user intentionally so that it does not enter the standby state. This can be done with the key switch provided on the remote controller or the main body of the television receiver. It can be set.

If the standby state is permitted, it is determined whether or not there is a synchronization signal based on the synchronization determination information (S4). If there is a sync signal, the switches SW1 and SW2 are kept closed (S10), and if there is no sync signal, the process proceeds to the next step (S5). In the next step, if there is a key input for canceling standby from the remote controller or the like, the switches SW1 and SW2 are kept closed (S1
0), if there is none, proceed to the next step (S6).

In the next step, the internal timer of the microcomputer 2 counts how long this state has continued as the elapsed time (S7), and the elapsed time must pass the preset time. Then step again (S
3), and if the elapsed time has passed the preset time, the process proceeds to the next step (S).
8). When the set time has passed, the switches SW1 and SW2
Is opened so that the horizontal drive signal and the vertical drive signal are not supplied (S9), and the process returns to step (S3) to repeat the same operation.

By the operation of the microcomputer 2 as described above, the switches SW1 and SW2 can be opened and closed with or without the synchronization signal. The time set by the timer is
Since the user can freely set the setting time by operating keys such as a remote controller instead of the setting time fixed in advance, the user can select the setting time according to the situation and the place of use.

Next, another embodiment will be described. FIG. 2 shows a second embodiment. In this drawing, the same reference numerals as those in FIG. 1 have the same functions, and the description thereof will be omitted. 3 is different from FIG. 1 in the arrangement of switches. That is,
In FIG. 3, 6 is a power supply circuit for constantly supplying power to the microcomputer 2 and the video signal processing circuit 1, 7 is a power supply circuit for supplying power to the horizontal output circuit 3 and the vertical output circuit 4, and 8 is an AC power plug. , SW3 are switches.

Next, only the operation different from that of FIG. 1 will be described. When the AC power plug 8 is connected to the commercial power supply, the power supply circuit 6 always works and the power supply is the microcomputer 2 and the video signal processing circuit 1.
Is supplied to. On the other hand, the power supply circuit 7 operates when the switch SW3 is closed, and supplies power to the horizontal output circuit 3 and the vertical output circuit 4. The power supply can be automatically turned on and off by making the microcomputer 2 configured as described above to perform the operation shown in the flowchart of FIG. Note that the switches SW1 and SW2 in the flowchart of FIG. 2 become the switch SW3 in FIG.

According to this embodiment, since the power supply to the horizontal output circuit 3 and the vertical output circuit 4 can be cut off directly, these circuits do not work and the power consumption can be reduced as compared with FIG. (In FIG. 1, since the horizontal output circuit 3 and the vertical output circuit 4 are supplied with power, a certain amount of power is consumed.) As another embodiment, FIG. 4 shows a third embodiment. Show. FIG. 4 shows an embodiment improved from FIG. 3, and only different points will be described. The difference from FIG. 3 is that the power supply circuit 9 that supplies power to each circuit is common, and the switch SW4 is provided only when power is supplied to the horizontal output circuit 3 and the vertical output circuit 4.
It is configured to be supplied via SW5. According to the third embodiment, there is an advantage that the power supply circuit 9 can be configured in common. The operation of the microcomputer 2 is the same as the flowchart of FIG. 2, and the switches SW1 and SW2 are the switches SW4 and SW5 in FIG.

By the way, in FIGS. 1, 3 and 4, the power supply to the horizontal output circuit 3 and the vertical output circuit 4 can be stopped,
Since the video signal processing circuit 1 has a configuration in which power is continuously supplied, power is continuously consumed correspondingly.

Another embodiment improved in order to solve this problem is shown in FIG. FIG. 5 shows a fourth embodiment, the configuration of which is basically the same as that of the third embodiment of FIG. 4 (the same figure number shows the same circuit), and is different from the video signal processing circuit 1. The point is that a switch SW6 for cutting off the power supply to is provided.

The microcomputer 2 operates according to the flow chart shown in FIG. That is, this flowchart is a modification of the flowchart shown in FIG. The operation will be described below based on the flowchart of FIG. The same step number performs the same operation.

First, the operation of steps S1 to S8 is the same as that described in the flow chart of FIG. It is determined whether or not the state where there is no synchronization signal has passed the preset time (S8) and is in the first standby state (S11). The first standby state is a state in which the switches SW4 and SW5 are opened to supply power to the horizontal output circuit 3 and the vertical output circuit 4 and continue supplying power to the video signal processing circuit 1. ,
If there is a sync signal, the video can be reproduced again.

As a result of the judgment, if it is not in the first standby state, the switches SW4 and SW5 are opened so as to be in the first standby state (S9), and the timer is reset (S13). Then, returning to step 3, the presence / absence of the sync signal is confirmed again, and the absence of the sync signal has passed a preset time (S8). Further, if the first standby state is set (S11), the switch SW6 To open the second standby state. This second standby state is
The switch SW3 is opened to shut off the power supply to the video signal processing circuit 1 and only supply the power to the microcomputer 2. By doing so, the power consumption of the video signal processing circuit 1 can be reduced.

When in the second standby state,
Images cannot be reproduced unless the user closes the switches SW4, SW5, and SW6 by operation to supply power to each circuit.

The set time of the timer for setting the first standby state and the set time of the timer for setting the second standby state may be the same or different from each other (for example, in the first standby state). Longer to shorten the transition time to the second standby state, or vice versa. Further, it goes without saying that these set times can be arbitrarily selected by the user.

[0032]

As described above, the present invention reduces power consumption by automatically turning off the power when no video signal is input and automatically turning on the power when the video signal is input. The effect is that the operator does not have to perform a troublesome operation.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the embodiment of the present invention.

FIG. 3 is a block diagram showing a second embodiment of the present invention.

FIG. 4 is a block diagram showing a third embodiment of the present invention.

FIG. 5 is a block diagram showing a fourth embodiment of the present invention.

FIG. 6 is a flowchart showing the operation of the fourth embodiment of the present invention.

[Explanation of symbols]

 1 Video signal processing circuit 1a Video signal processing circuit 1b Synchronous circuit 2 Microcomputer 3 Horizontal output circuit 4 Vertical output circuit 5 Cathode ray tube 10 Deflection yoke SW1 switch SW2 switch

Claims (9)

[Claims] 1. A video signal input means for inputting a video signal, a video output signal processing means for receiving a video signal from the video signal input means and supplying a video output to a cathode ray tube, and a video from the video signal input means. Sync circuit means for extracting a sync signal of a signal and outputting a horizontal drive signal and a vertical drive signal from the sync signal; a video signal detection means for detecting the presence or absence of a video signal from the video signal input means; The horizontal output signal and the vertical output signal are supplied to the deflection yoke based on the drive signal and the vertical drive signal,
Further, it is characterized by comprising a deflection output means for supplying a high voltage to the cathode ray tube, and a control means for stopping the operation of the deflection output means by the output of the video signal detection means which detects the absence of the video signal. Television receiver. 2. The television receiver according to claim 1, wherein the control means stops the operation of the deflection output means within a first predetermined time from the output when the absence of a video signal is detected. Characteristic television receiver. 3. The television receiver according to claim 2, wherein an operator can arbitrarily set the first predetermined time. 4. The television receiver according to claim 3, wherein the video signal detecting means detects the presence or absence of a video signal based on the presence or absence of a synchronizing signal of the video signal. 5. The television receiver according to claim 4, further comprising: first switch means for connecting the synchronizing circuit means and the deflection output means, wherein the control means is the video signal detecting means. A television receiver characterized in that the first switch means is controlled by an output that detects the absence of a video signal to stop the operation of the deflection output means. 6. The television receiver according to claim 4, wherein the video output signal processing means, the synchronizing circuit means, and the control means always supply power to the first power supply means, and the deflection output means. Second power supply means for supplying power to the second power supply means, and second switch means for cutting off the power supply of the second power supply means, wherein the control means is the video signal detection means. The television receiver characterized in that the operation of the deflection output means is stopped by controlling the second switch means by an output that detects the absence of the video signal. 7. The television receiver according to claim 6, wherein the first power supply means and the second power supply means are one.
A television receiver comprising a single power supply means. 8. The television receiver according to claim 7, further comprising third switch means for cutting off power supply from the power supply means to the video output signal processing means and the synchronizing circuit means, The control means detects that there is no video signal from the video signal detecting means, and then outputs the second signal after the first predetermined time.
The television receiver characterized in that the switch means is controlled to stop the operation of the deflection output means, and the power supply is cut off by the third switch means after the second predetermined time has elapsed. 9. The television receiver according to claim 8, wherein an operator can arbitrarily set the first predetermined time and the second predetermined time.