JPS622892Y2 - - Google Patents

Description

[Detailed description of the invention] When driving different first and second loads, a predetermined power is always supplied to one of the loads regardless of the power supply state to the other load. There are times when I want to. Remotely controllable television sets are a good example. That is, in this television receiver, the driving power for the receiving system for remote control signals is always a specified power source regardless of the reception state in the receiver, that is, regardless of whether the television receiver is operating or not. This is because they need to be supplied.

Figure 1 shows an example of a power supply device suitable for application to this remotely controllable television receiver, in which 1 is a commercial AC source, SW ₁ is a main power switch, and 2 is a full-wave rectifier circuit. The rectified output is supplied as operating power to the television receiver set 4. 5 indicates a smoothing capacitor, and AC source 1
A remote switch _SW2 is connected in series with one of the power supply paths _la , the on/off state of which is controlled by remote control, which will be described later.

7 is a remote control circuit, 7A is a transmission system, 7B
is a receiving system, 8 is a transmitting circuit, and 9T is a transmitter. The ultrasonic signal (remote control signal) emitted from the transmitter 9T is sent to the receiver 9 provided in the receiving system 7B.
R is received, and its output is supplied to a receiving circuit 11 and then to a control circuit 12, where a desired remote control operation is performed. In this example, only those for turning the power on and off are shown. Therefore, transistor Q is a transistor for controlling remote switch _SW2 .

It is necessary to always supply a predetermined operating power source to the receiving system 7B regardless of the operating state of the television receiver set 4. Therefore, in this example, a power transformer 14 is provided in parallel with the full-wave rectifier circuit 2, and its output is supplied to the half-wave rectifier circuit 15, so that the desired DC voltage is used as the operating power source in the receiving system 7B. The half-wave rectifier circuit 15 further includes a relay 1 for controlling the remote switch SW ₂ mentioned above.
6 is connected, and by controlling the control transistor Q, the remote switch _SW2 is turned on and off.

Incidentally, in order to always supply the operating power to the receiving system 7B regardless of the operating power to the receiver set 4, one terminal of the primary coil in the power transformer 14 is led out between the remote switch SW ₂ and the AC source 1. It is easy to understand what needs to be done.

The degauss circuit 20 is composed of a degauss coil 20A and a positive temperature sensing element 20B, and the degauss circuit 20 is connected in parallel with the AC source 1. With this configuration, the above-mentioned object can be achieved, but as is clear from the figure, the expensive power transformer 14 must be used, so it is not economical.

In this respect, when the circuit is configured as shown in FIG. 2, the circuit configuration is extremely simple, resulting in a more economical configuration. That is, in this example, the output of the full-wave rectifier circuit 2 is configured to be supplied to the receiver set 4 via the remote switch SW ₂ , and a constant voltage circuit 25 is provided on the output side of the full-wave rectifier circuit 2. The regulated voltage is used as an operating power source in the receiving system 7B. Further, the relay 16 also utilizes this constant voltage power source.

In this way, the receiving system 7B can always be supplied with a predetermined operating power without requiring the power transformer 14, but since the remote switch SW ₂ is connected to the rectified output side, this remote Switch SW ₂ must be for DC.

When a switch is provided in the DC power supply path, sparks are likely to occur when the switch is turned on or off, and a structure is usually designed to prevent this, which makes the remote switch SW ₂ expensive. Furthermore, in this circuit configuration, since the degauss circuit 20 is connected before the full-wave rectifier circuit 2, no rush current flows when the remote switch SW ₂ is turned on, that is, when the main power switch SW ₁ is turned on. A sufficient degauss effect cannot be obtained because the lash current flows only when this occurs.

The present invention takes these points into consideration and eliminates the above-mentioned drawbacks by having an extremely simple configuration. The power supply device according to the present invention will be described in detail with reference to FIG. 3. In this example, the power supply device according to the present invention is applied to a power supply device for a remotely controllable television receiver as described above.

In the present invention, the rectified output (relatively high power supply voltage) of the bridge-configured full-wave rectifier circuit 2 is used as the operating power source for the receiver set (first load) 4, and
A half-wave rectifier circuit 15 is connected to one power supply path l _a of the AC source 1, and its rectified output (relatively low power supply voltage) is used as an operating power source in the receiving system 7B.
In this example, the output of the half-wave rectifier circuit 15 is once supplied to the constant voltage circuit 25, and the constant voltage output is used as an operating power source. The relay 16 utilizes the rectified output of the half-wave rectifier circuit 15 described above.

The remote switch SW ₂ to be controlled by the relay 16 is connected in series between the connection point p ₁ and the power supply path of the full-wave rectifier circuit 2. One end of the degauss circuit 20 is connected to a power supply path between the remote switch SW ₂ and the full-wave rectifier circuit 2.

When the power supply device is configured in this way, the desired operating power can be supplied to the receiving system 7B regardless of the power control state of the remote switch SW ₂ , and the degauss circuit 20 can be inserted after the switch SW ₂ . Therefore, whenever this remote switch is turned on, a rush current flows through the degauss circuit 20.
Since a demagnetizing effect is applied in response to power supply control, the initial objective can be achieved. Further, since this remote switch _SW2 is connected in series to the AC power supply path l _a , an AC switch can be used. As explained above, according to the power supply device according to the present invention, power consumption can be reduced because the power supply voltage for remote control is kept low, and the power supply control state for the receiver set 4 can be controlled without the need for an expensive power transformer. The desired operating power can always be supplied to the receiving system 7B regardless of the situation. Moreover, according to this configuration, since the remote switch SW ₂ is provided on the AC current path, it is possible to use a relatively inexpensive AC switch. Furthermore, with this configuration, the degaussing action can be performed every time the operating power source for the receiver set 4 is controlled.

In the above embodiment, the device of the present invention is applied to a television receiver that can be controlled remotely.
Even in the case of a television receiver or the like with a built-in timer device, it is necessary to supply a predetermined operating power to the timer device regardless of the power supply to the receiver set 4. It can also be applied to television receivers.

Furthermore, if you want to configure a television receiver or the like equipped with an electronic tuner device so that the channel you were watching before the power was turned off can be selected the next time the power is turned on, the channel selection It is necessary to supply the device with a constant operating voltage regardless of the power source of the receiver set 4. Even in such cases, the power supply device according to the present invention can be applied. Of course, it is not limited to television receivers, and when driving different first and second loads, one of the loads is always supplied with a predetermined power regardless of the power supply state of the other load. Needless to say, it is suitable for application to such devices.

[Brief explanation of the drawing]

1 and 2 are connection diagrams showing an example of a conventional power supply device, and FIG. 3 is a connection diagram showing an example of a power supply device according to the present invention. 1 is an AC source, 2 is a full-wave rectifier circuit, 4 is a receiver set as a first load, SW ₂ is a remote switch, 15 is a half-wave rectifier circuit, and 7B is a receiving system (second load).

Claims (1)

[Scope of utility model registration request] The first and second terminals of the alternating current source are connected between a pair of vertices of a diode bridge, one of the other pair of vertices of the diode bridge is connected to a reference potential point, and a first capacitor is connected to the other. A half-wave rectifying diode is directly connected to the second terminal of the AC source without going through a transformer, and the half-wave rectifying diode is A second capacitor is connected between the output side and the reference potential, and the alternating current is supplied from the second terminal of the alternating current source through the half-wave rectifying diode, the second capacitor, and one side of the diode bridge. forming a closed loop to a first terminal of the AC source, supplying a relatively low voltage from the half-wave rectifier diode to a second load for remote control; A power switch for controlling the first load is provided between the diode bridges, and power is constantly supplied to the second load regardless of whether the power switch is on or off. A power supply device in which turning on and off of the power switch is controlled by a second load.