JPH0314949Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a remote control device for a switching regulator including a DC-AC converter.

[Prior Art] Fig. 2 is a circuit diagram of a conventional device, in which 10 is an input AC commercial power supply, 11 is a rectifying diode, 12 is a smoothing capacitor, 13 is a resistor, and 14 is a DC-AC circuit. The converter, 15 is a zener diode, and 16 is a transformer, these are shown in block 1. 17 is a remote switch on the primary side, 21, 2
2 and 23 are diodes, electrolytic capacitors, and resistors representing the secondary side load circuit, and these are shown as block 2.

In the above-described device, when the switch 17 is closed and turned on, the DC-AC converter 14 is energized and its output signal is transmitted to the transformer 16 and the transmission line 2.
0 and is transmitted to its secondary side to obtain a DC voltage,
This is supplied to the load resistor 23. When the switch 17 is released to turn off, this state is transmitted to the DC-AC converter 14 via the transmission line 18, and the reference voltage determined by the Zener diode 15 is supplied to the DC-AC converter 14. to block that operation.

[Problems to be solved by the invention] In the conventional remote control device as described above,
Since the switch 17 on the primary side is directly connected to the second block 2, interference due to electromagnetic induction occurs between the transmission lines between the primary and secondary sides. Another problem is that the primary voltage is directly applied to the switch 17 via the transmission line 18.

This invention was made to solve the above-mentioned problems, and aims to provide a remote control device in which the primary side voltage is not directly applied to the remote switch 17.

[Means for solving the problem] The remote control device according to this invention controls the output of an oscillator according to the on/off operation of a switch,
This output is then compared with a reference voltage, and the operation of the DC-AC converter is controlled based on the comparison result.

[Operation] In this invention, since the operation of the DC-AC converter is indirectly controlled by the operation of the remote switch, the primary voltage is not directly applied to the remote switch.

[Embodiment of the invention] Fig. 1 is a circuit diagram showing a remote control device according to an embodiment of the invention, and the same parts as those of the conventional device shown in Fig. 2 are designated by the same reference numerals. Explanation will be omitted. 30 is a transformer consisting of a primary winding 31 and a secondary winding 32. A remote switch 17 is connected to the primary winding 31 via a transmission line 18, and an oscillator 33 and a diode 34 are connected to the secondary winding 32. Also, diode 3
A series element of a diode 35 and a resistor 36 is connected across the resistor 4, and the voltage developed across the resistor 36 is introduced into one input terminal of a comparator 38. Note that the reference voltage (Vref) from the reference power supply 37 is supplied to the other input terminal.
The output signal of this comparator 38 is sent to the DC-AC converter 14.
is supplied to

In the remote control device configured as described above, only the excitation current flows through the transformer 30 when the remote switch 17 is currently off. Therefore, since the voltage across the resistor 36 is lower than the voltage (Vref) of the reference power supply 37, the DC-AC converter 14
doesn't work. On the other hand, when the remote switch 17 is on, the primary winding 31 of the transformer 30 is shorted, which causes the reluctance of the transformer 30 to be zero and the output of the oscillator 33 to be connected to the diode 3.
5, and the voltage across the resistor 36 becomes equal to or higher than the reference voltage (Vref). As a result, the DC-AC converter 14 operates, and its output signal is converted to DC via the transformer 16 and the transmission line 20, and the DC signal is supplied to the load resistor 23 on the secondary side.

[Effects of the invention] As detailed above, according to this invention, since the primary voltage is not directly applied to the remote switch, there is no interference between the primary and secondary.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a remote control device showing an embodiment of this invention, and FIG. 2 is a circuit diagram of a conventional device. In the figure, 10 is a commercial power supply, 11, 21, 34, 3
5 is a diode, 12 and 22 are electrolytic capacitors,
14 is a DC-AC converter, 15 is a Zener diode, 16 and 30 are transformers, 17 is a remote switch,
33 is an oscillator, 37 is a reference power supply, and 38 is a comparator. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] a first block 1 comprising a DC-to-AC converter 14 for converting an input AC signal into DC and then reconverting the DC signal into an AC signal, and an output signal of said converter to a second block 2 via a transmission line 20; means 21, 22 for converting the transmitted AC signal into DC and supplying it to the load 23; and controlling the operation of the DC-AC converter by operating the remote switch 17 in the second block. In a switching regulator, a transformer 30 having a primary winding 31 and a secondary winding 32 which is shorted/opened by the operation of the remote switch and an AC oscillator 33
and detectors 34, 35, 36, a reference power source 37, and a comparator 38, the detector receives and detects the output of the AC oscillator via the primary winding, and the comparator detects the output of the reference power source. The voltage is compared with the output of the detector to provide the DC-AC converter with an output for energizing/blocking the DC-AC converter 14 in accordance with the operation of the remote switch. Remote control device for switching regulator.