JPH08286773A - Power unit - Google Patents

Abstract

PURPOSE: To miniaturize a power unit by connecting a specified capacitor in series to the specified number of capacitors which are connected in series when current flows through a rectifier circuit and connecting it in parallel to the specified number of the capacitors which are connected in series when current does not flow. CONSTITUTION: Voltage stabilized by first and second constant voltage diodes 7 and 8 is supplied to first and second loads 10 and 11. Voltage decided by a constant voltage circuit 9 is supplied to a third load 12. Then, respective loads stably operate. The increase of current can be accumulated in a third capacitor 6 and a fourth capacitor 13 for the voltage boost of a commercial AC power source 1 by non-stabilizing either one of the plural serial power sources constituted of first, second and third capacitors 4-6 connected in series. The voltage drop required for generating DC power from the power source 1 can be reduced and loss power can be reduced by the first constant voltage diode 7 and the second constant voltage diode 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device which is not insulated from a commercial AC power supply used in devices such as jar pots, rice cookers, irons and vacuum cleaners.

[0002]

2. Description of the Related Art A conventional power supply device has a structure shown in FIG. 4 or FIG. In the structure shown in FIG. 4, a rectifier circuit 1 connected to a commercial AC power source, a resistor 25, a capacitor 26, and a constant voltage diode 27 constitute a DC power source, and loads 28, 29, and 30 are connected to this DC power source. Has become. That is, the DC power supply supplies current to these three loads 28, 29, 30. Therefore, the DC power supply must have a large current capacity.

The one shown in FIG. 5 is used when the three loads operate at different DC power supply voltages.
In this case, 31 is the load that requires the highest voltage, and the load 33 connected to the load 31 via the voltage drop means 32 operates at the second highest DC power supply voltage. In addition, the load 35 connected to the load 33 via the voltage drop means 34
Operates at a lower operating voltage. In this case as well, the DC power supply needs a current capacity capable of supplying a current to the three loads 31, 33, and 35.

The same applies to a power supply device using a transformer or the like.

[0005]

As described above, the conventional power supply device supplies electric power to a plurality of loads.
It requires a large voltage drop and a large current to create a DC power supply from a commercial AC power supply. In addition, it is necessary to maintain the voltage for a certain period of time in order to cope with the momentary power failure of the commercial AC power supply, and therefore it is necessary to set the capacity of the capacitor constituting the DC power supply to a large value. Therefore, there are problems that the size of the power source becomes large, the heat generation becomes large, and it is necessary to use a component having a large power rating.

The present invention solves the problem of such a conventional structure, and can reduce the magnitude of the voltage drop required when a DC power supply is made from a commercial AC power supply.
Therefore, the loss power can be reduced, the ripple voltage can be reduced even if the capacity of the capacitor that constitutes the DC power supply is small, and a small capacity capacitor can be used for the momentary power failure of the commercial AC power supply. A first object of the present invention is to provide a power supply device capable of reducing the component rating of the constant voltage diode.

Further, to provide a power supply device capable of reducing the power loss in the constant voltage diode to be used and using the (n + 1) th capacitor and the (n + 2) th capacitor having a low withstand voltage rating. Is the second purpose.

Further, the first to n-th loads can be selected so that they can be operated by non-DC, so that the first to n-th capacitors can be eliminated, and the number of parts to be used is reduced and the size and weight are reduced. A third object is to provide a power supply device.

[0009]

The first means of the present invention for achieving the first object is a rectifier circuit and a resistor connected to one end of a commercial AC power source, and an n connected in series connected to the resistor. Constant voltage diodes, n capacitors and n loads connected in parallel to the respective constant voltage diodes, (n + 1) th capacitor and (n + 1) th capacitor connected in series to the n capacitors. ) Th capacitor connected in parallel to the (n + 1) th load and a control circuit connected between the (n + 1) th capacitor and the other end of the commercial power source, the control circuit being a rectifier circuit. When a current flows, the (n + 2) th capacitor is connected in series with the n capacitors,
When no current flows in the rectifier circuit, the power supply device is connected in parallel with the first to (n + 1) th capacitors connected in series.

The second means of the present invention for achieving the second object is to set the zener voltage of the (n + 1) th constant voltage diode to be equal to or lower than the withstand voltage of the (n + 1) th capacitor. In use, the power supply device operates at a voltage equal to or lower than the Zener voltage, and the constant voltage diode protects the (n + 1) th capacitor when the voltage of the commercial AC power supply rises from the rated voltage.

A third means of the present invention for achieving the third object is to provide a rectifying circuit and a resistor connected to one end of a commercial AC power source, and n constant voltage diodes connected in series to the resistor. , N loads which are connected in parallel to the respective constant voltage diodes and can operate even with a non-DC voltage, and a (n +) th load connected in series to the n constant voltage diodes.
The (1) th capacitor and the (n + 1) th load connected in parallel to the (n + 1) th capacitor, and the control circuit connected between the (n + 1) th capacitor and the other end of the commercial power supply. And the n loads are the (n
The power supply device operates according to a command from the +1) th load.

[0012]

According to the first means of the present invention, when the control circuit causes a current to flow through the rectifier circuit, the (n + 1) th capacitor is connected in series with the (n + 1) th capacitor, and the rectifier circuit receives the current. When it does not flow, it acts so as to be connected in parallel with the (n + 1) capacitors connected in series, which makes it possible to make a compact power supply device.

The second means of the present invention is to set the Zener voltage of the (n + 1) th constant voltage diode to be equal to or lower than the withstand voltage of the (n + 1) th capacitor, and to set the (n + 1) th capacitor and the (n + 2) th capacitor. It is possible to make a power supply device with a smaller withstand voltage rating of the second capacitor.

The third means of the present invention is to select the n loads to be connected that can operate even at a non-DC voltage (n + 1).
As can be controlled by the command from the second load,
The power supply is designed to reduce the number of capacitors used.

[0015]

【Example】

(Embodiment 1) A first embodiment of the power supply device of the present invention will be described below. FIG. 1 is a block diagram showing an electric circuit of this embodiment. A rectifier circuit 2 and a resistor 3 are connected to one end 1a of the commercial AC power supply 1. The rectifier circuit 2 is a half-wave rectifier diode in this embodiment. At the other end of the resistor 3, a first constant voltage diode 7 and a second constant voltage diode 8 which are n constant voltage diodes are connected in series. That is, in this embodiment, n = 2. A first capacitor 4 and a first load 10 are connected in parallel to the first constant voltage diode 7, and a second capacitor 5 and a second load 11 are connected in parallel to the second constant voltage diode 8. . The second condenser 5 is connected in series with the (n +
1) The third capacitor 6, which is the first capacitor, is connected. A constant voltage circuit 9 is connected in parallel to the third capacitor 6, and a third load 12 which is a (n + 1) th load is connected in parallel to the constant voltage circuit 9. In this embodiment, the third load 12 connected to the third capacitor 6 is via the constant voltage circuit 9, but it does not mean that the constant voltage circuit 9 must be used. Is. A control circuit 14 including a fourth capacitor 13, which is a (n + 2) th capacitor, is connected between the third capacitor 6 and the other end 1b of the commercial AC power supply 1. The control circuit 14 includes the diode 1
4a, 14b, 14d, 14e, a transistor 14f, a resistor 14c, and the fourth capacitor 13.

The operation of this embodiment will be described below. When one end 1a side of the commercial AC power supply 1 has a positive polarity, the rectifier circuit 2, the resistor 3, the first capacitor 4, the second capacitor 5, and the third capacitor 6 are fed from the commercial AC power supply 1.
From the diode 14a and the fourth capacitor 13 / diode 14e, a first closed circuit that returns to the commercial AC power supply 1 is formed, and a current flows. Further, the current flowing through the resistor 3 is from the resistor 14c to the diode 14d / commercial AC power supply 1
It constitutes a second closed circuit of and flows. At this time, a voltage of about 0.6 V is generated in each of the diodes 14d and 14e. Therefore, the voltage between the base and emitter of the transistor 14f becomes zero. As a result, the transistor 14f is turned off.

The polarity of the commercial AC power supply 1 is reversed and the terminal 1b
When the side becomes positive, the diodes 14d and 14e
No current flows through it. At this time, transistor 14f
Uses the electric charge stored in the fourth capacitor 13 as a power source, and turns on the transistor 14f from the diode 14b using the resistor 14c as a bias resistor. Transistor 1
When 4f is turned on, from the fourth capacitor 13, the first capacitor 4, the second capacitor 5, and the third capacitor 6 connected in series through the diode 14b are connected.
A current flows by forming a closed circuit from the collector of the transistor 14f to the emitter of the transistor 14f via the. Therefore, the fourth condenser 13
Is equivalently connected in parallel to the first capacitor 4, the second capacitor 5, and the third capacitor 6 connected in series.

That is, in the control circuit 14 of this embodiment, every time the polarity of the voltage of the commercial AC power source 1 changes, the connection state of the fourth capacitor 13 is connected in series to the first capacitor 4 and the second capacitor 5. -The third capacitor 6 is repeatedly connected in series and then in parallel. Further, the voltage of the fourth capacitor 13 in this parallel connection state is almost equal to that of the first capacitor 4.
-The voltage is equal to the sum of the voltages of the second capacitor 5 and the third capacitor 6.

Further, in this embodiment, a constant voltage diode is not connected to the third capacitor 6. Therefore, when the voltage of the commercial AC power supply 1 rises from the rated voltage, it is possible to reduce the increase in power loss.

That is, when the third constant voltage diode is connected to both ends of the third capacitor 6, even if the voltage of the commercial AC power supply 1 rises, the first capacitor 4 and the second capacitor 5・ The voltage of the third capacitor 6 is
First constant voltage diode 7 and second constant voltage diode 8
And is fixed by the operating voltage of the third constant voltage diode. Therefore, the voltage of the fourth capacitor 13 is also almost fixed. Therefore, the amount of increase in the voltage of the commercial AC power supply 1 is all applied to the resistor 3, and the current input from the commercial AC power supply 1 increases by this amount. The increased current acts as a loss current on the first constant voltage diode 7, the second constant voltage diode 8 and the third constant voltage diode, and eventually leads to an increase in power consumption of the constant voltage diode. It is a thing. In this respect, according to this embodiment, since the third constant voltage diode is not used, when the voltage of the commercial AC power supply 1 increases, the charging current of the third capacitor 6 increases, Therefore, the voltage of the capacitor 6 will increase. Therefore, the voltage of the fourth capacitor 13 also rises, and the amount of increase in the voltage of the commercial AC power source 1 is distributed to the resistor 3, the third capacitor 6 and the fourth capacitor 13. That is, the increase in the input current due to the increase in the voltage of the commercial AC power supply 1 is smaller than that when the third constant voltage diode is provided. Therefore, the current flowing through the first constant voltage diode 7 and the second constant voltage diode 8 can be suppressed to a small amount, and the increase in loss power can be reduced.

As described above, the first load 10 and the second load 11 are supplied with the voltage stabilized by the first constant voltage diode 7 and the second constant voltage diode 8, respectively.
Further, the voltage determined by the constant voltage circuit 9 is supplied to the third load 12, and each load can operate stably.

As described above, according to this embodiment, the first capacitor 4 and the second capacitor 5 connected in series are
By destabilizing one of the plurality of series power supplies that the third capacitor 6 constitutes, the commercial AC power supply 1
The increase in current with respect to the increase in voltage of can be accumulated in the third capacitor 6 and the fourth capacitor 13,
It is possible to reduce the magnitude of the voltage drop required when creating a DC power supply from the commercial AC power supply 1, and thus to reduce the power loss in the first constant voltage diode 7 and the second constant voltage diode 8. Is.

Since the first load 10, the second load 11, and the third load 12 are connected in series to the commercial AC power supply 1, the input current supplied from the commercial AC power supply is small. As a result, the ripple voltage can be reduced even if the capacity of the capacitor that constitutes the DC power supply is small, and a small-capacity capacitor can handle the instantaneous power failure of the commercial AC power supply. .
Further, the component rating of the constant voltage diode used can be small.

(Second Embodiment) Next, a second embodiment of the present invention will be described. In this embodiment, as shown in FIG. 2, the third constant voltage diode 15 is connected to both ends of the third capacitor 6. At this time, the Zener voltage of the third constant voltage diode 15 is set to be lower than the withstand voltage of the third capacitor 6 so that the constant voltage diode 15 does not operate at the rated voltage of the commercial AC power supply 1. .

The operation of this embodiment will be described below. When the voltage of the commercial AC power supply 1 is the rated voltage, the voltage of the third capacitor 6 is equal to or lower than the Zener voltage of the third constant voltage diode 15, and the same operation as in the first embodiment is performed. However, when the voltage of the commercial AC power supply 1 rises from the rated voltage, the voltage of the third capacitor 6 also rises. When this voltage rises above the Zener voltage of the third constant voltage diode 15, the voltage of the third capacitor 6 is limited by the Zener voltage of the third constant voltage diode 15.

That is, according to this embodiment, the third constant voltage diode 15 is connected to operate so as to protect the third capacitor 6 only when the commercial AC power supply 1 rises from the rated voltage to a voltage exceeding a certain value. Therefore, the withstand voltage rating of the third capacitor 6 can be reduced, and the size of the device can be reduced. Further, when the rise value of the voltage of the commercial AC power supply 1 is up to the fixed value, the same effect as that of the first embodiment is obtained.

(Embodiment 3) Next, a third embodiment of the present invention will be described. In this embodiment, as shown in FIG. 3, the structure of the power supply device is extremely simple. That is, a rectifier circuit 2 and a resistor 3 are connected in series to one end 1a of the commercial AC power supply 1, and a first constant voltage diode 7 and a second constant voltage diode 8 are connected in series to the resistor 3. There is. Each of these two constant voltage diodes,
The fourth load 16 and the fifth load 17 are connected in parallel. A third capacitor 6 is connected in series with the second constant voltage diode 8. A constant voltage circuit 9 and a sixth load 18 are connected in parallel to the third capacitor 6. The control circuit 14 described in the first embodiment is connected between the third capacitor 6 and the terminal 1b of the commercial AC power supply 1.

At this time, in the present embodiment, as the fourth load 16 and the fifth load 17, those operable with a non-DC voltage,
For example, the LED is selected, and the fourth load 16 and the fifth load 17 are operated by the instruction of the sixth load 18. That is, a control circuit such as a microcomputer is used as the sixth load 18.

The operation of this embodiment will be described below. In this embodiment, for the fourth load 16 and the fifth load 17, for example, LEDs that can operate even with a non-DC voltage are selected. Therefore, if there is an instruction from the sixth load 18, even when the commercial AC power supply 1 is not supplied, the operation by the pulsating current due to the charge stored in the fourth capacitor 13 can be performed. It is a thing.

That is, according to this embodiment, the commercial AC power supply 1
The fourth load 16 and the fifth load 17 can be operated by the supply of the pulsating current by the fourth capacitor 13 and. Therefore, it is not necessary to use the first capacitor 4, the second capacitor 5, and the third capacitor 6 used in the first and second embodiments, and the number of parts used can be reduced. That is, a simple and small power supply device can be realized.

[0031]

According to the first means of the present invention, a rectifier circuit and a resistor connected to one end of a commercial AC power source, n constant-voltage diodes connected in series connected to the resistor, and the respective constant-voltage diodes. N capacitors and n loads connected in parallel to, and the (n + 1) th capacitor and (n) connected in series to the n capacitors.
The (n +) th capacitor connected in parallel to the (+1) th capacitor
The control circuit includes a 1) th load and a control circuit connected between the (n + 1) th capacitor and the other end of the commercial power supply. The control circuit is connected to the (n +) th circuit when current flows through the rectifier circuit.
2) The second condenser is connected in series with the n condensers, and when no current flows in the rectifier circuit, it is connected in parallel with the first to (n + 1) th condensers connected in series. The size of the voltage drop required when creating a DC power supply from a power supply can be reduced, so the loss power can be reduced, and the ripple voltage can be reduced even if the capacity of the capacitor that constitutes the DC power supply is small, and commercial AC It is possible to realize a power supply device that can handle a momentary power failure of the power supply with a small-capacity capacitor and can reduce the component rating of the constant voltage diode used.

The second means of the present invention is particularly the (n + 1) th.
The zener voltage of the th voltage regulator is the (n + 1) th
The voltage is set to be equal to or lower than the withstand voltage of the second capacitor, operates at a voltage lower than the Zener voltage during normal use, and the constant voltage diode protects the (n + 1) th capacitor when the voltage of the commercial AC power supply rises from the rated voltage. As a result, the power loss in the constant voltage diode used can be reduced, and the (n + 1) th capacitor and the (n +) th capacitor
The second is to realize a power supply device that can use a capacitor having a low withstand voltage rating as the second capacitor.

The third means of the present invention is that a rectifier circuit and a resistor connected to one end of a commercial AC power source, n constant-voltage diodes connected in series connected to the resistor, and each of the constant-voltage diodes. N loads that can be operated even with non-DC voltage connected in parallel, and a (n + 1) th capacitor and a (n + 1) th capacitor that are connected in parallel to the n constant voltage diodes in series. A (n + 1) th load and a control circuit connected between the (n + 1) th capacitor and the other end of the commercial power source are provided, and the n loads are instructed by the (n + 1) th load. As a structure for operation, the first to nth capacitors can be eliminated, and a compact and lightweight power supply device in which the number of parts used is reduced is realized.

[Brief description of drawings]

FIG. 1 is a block diagram showing electrical connection of a power supply device that is a first embodiment of the present invention.

FIG. 2 is a block diagram showing electrical connection of the power supply device according to the second embodiment.

FIG. 3 is a block diagram showing the electrical connection of the power supply device according to the third embodiment.

FIG. 4 is a block diagram showing electrical connection of a conventional power supply device.

FIG. 5 is a block diagram showing electrical connection of another conventional power supply device.

[Explanation of symbols]

 1 Commercial AC Power Supply 2 Rectifier Circuit 3 Resistance 4 First Capacitor 5 Second Capacitor 6 Third Capacitor 7 First Constant Voltage Diode 8 Second Constant Voltage Diode 10 First Load 11 Second Load 12 Second Third load 13 Fourth capacitor 14 Control circuit 15 Third constant voltage diode 16 Fourth load 17 Fifth load 18 Sixth load

Claims (3)

[Claims] 1. A rectifier circuit and a resistor connected to one end of a commercial AC power source, n constant-voltage diodes connected in series connected to the resistor, and n capacitors connected in parallel to the respective constant-voltage diodes. And n loads, and (n +) connected in series to the n capacitors.
The (1) th capacitor and the (n + 1) th load connected in parallel to the (n + 1) th capacitor, and the control circuit connected between the (n + 1) th capacitor and the other end of the commercial power supply. The control circuit includes a (n + 2) th capacitor connected in series with the n capacitors when a current flows in the rectifier circuit, and a first to a first (first) connected in series when no current flows in the rectifier circuit. A power supply device connected in parallel with the (n + 1) th capacitor. 2. The zener voltage of the (n + 1) th constant voltage diode is set to be equal to or lower than the withstand voltage of the (n + 1) th capacitor, and operates at a voltage equal to or lower than the zener voltage during normal use, and the voltage of the commercial AC power supply is The power supply device according to claim 1, wherein the constant voltage diode protects the (n + 1) th capacitor when the voltage rises from the rated voltage. 3. A rectifier circuit and a resistor connected to one end of a commercial AC power source, n constant-voltage diodes connected in series connected to the resistor, and a non-DC voltage connected in parallel to each of the constant-voltage diodes. N operable loads, a (n + 1) th capacitor connected in series to the n constant voltage diodes and a (n + 1) th load connected in parallel to the (n + 1) th capacitor, The control circuit according to claim 1, which is connected between the (n + 1) th capacitor and the other end of the commercial power supply, wherein the n loads are power supplies that operate according to a command from the (n + 1) th load. apparatus.