JPH08251837A - Commercial power battery backup circuit - Google Patents

Abstract

PURPOSE: To back up an apparatus completely at the time of power failure by forming a circuit for switching the circuit at the time of charging or discharging on the battery side, and mounting a remote switch at an AC plug for prevention of waste of battery power. CONSTITUTION: An AC relay 22 for the input monitor of a commercial power source is connected to the primary side of input. When an input power source is energized, sensing current passes through an AC relay 22, 30 that a relay contact 20 formed in a battery discharge circuit 23 on the secondary side opens, and a connection between a battery 15 and a load 18 is shut down. A remote switch 21 in a discharge circuit 23 detects that an AC plug 12 is disconnected from an AC receptacle 11 and turns OFF, regardless of battery backup operation due to the power failure of the commercial power, abnormal drop of its output voltage or the like, thereby a power feed route to a load 18 from the battery 15 being shut down forcibly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply circuit for general household / commercial equipment that uses a commercial power supply, and in particular, the power is supplied from the commercial power supply via an AC outlet plug (hereinafter referred to as AC plug), The present invention relates to a commercial power source battery backup circuit that switches to a backup battery power source in the event of a power failure and continues its operation.

[0002]

2. Description of the Related Art Generally, in a communication device, for example, a primary battery or a secondary battery is used for backing up the device when a commercial power supply fails. In the above device, if the user intentionally disconnects the AC plug 12 from the outlet 11, that is, if the user determines that it is not necessary to back up the device, whether the commercial power supply has a power failure or the device is used. It was not possible for the person to judge whether he wanted to stop the equipment by intentionally pulling out the AC plug 12.

FIG. 8 shows a configuration example of a conventional commercial power source battery backup circuit. In FIG. 8, the AC power input from the commercial power outlet 11 is converted by the AC / DC converter 13 in a steady state and then supplies power to the load (device) 18 side,
The backup battery 15 is constantly charged by the floating charging method.

The battery 15 (generally a nicad battery) is
Charged with constant current. Therefore, the battery 15 and AC / D
A charging current control circuit 16 for limiting the charging current is provided in the charging loop with the C converter 13. As the charging current limiting circuit 16, a simple constant current circuit including a transistor and a resistor is used. The backflow prevention diode 14 is connected to the battery
The current that tries to flow into the C / DC converter 13 is prevented. The discharging diode 17 is used to disconnect the charging current limiting circuit 16 from the discharging loop between the battery 15 and the load (device) 18.

[0005]

In the case of the above-mentioned conventional example, when a failure such as a power failure or a voltage drop occurs in the input commercial power source, power is immediately supplied from the battery 15 to the load 18 side. Along with this, when the AC plug 12 is intentionally removed from the outlet 11 for the purpose of stopping the use of the device, the power is supplied from the battery 15 to the load 18 side.
In the latter case, the electric power of the battery 15 is wastefully consumed and the battery 15 is discharged to the final voltage.
To operate the device, the AC plug 12 is inserted into the AC outlet 11 to supply power to the load (device) 18, and the battery 15 is recharged.

However, when a failure such as a power failure occurs during the charging process, the battery 15 before the full charge is reached.
Cannot supply sufficient backup power to the load (device) 18, and as a result, the reliability of the operation of the load (device) 18 is impaired.
Further, the battery 15 used for backing up such a device is originally not suitable for the cyclic use of charging / discharging, and if the charging / discharging is repeated many times, the battery 1 is not used.
There was a problem that the life of 5 was shortened.

Therefore, in view of the above-mentioned various problems, an object of the present invention is to prevent useless consumption of the battery and to reliably back up the equipment in the event of a power failure. It is intended to provide a commercial power supply battery backup circuit for appropriately performing battery backup by judging whether the power supply is disconnected or not, and an AC plug structure using the same. That is, the battery side has a circuit for switching the circuit at the time of charging / discharging, and the AC plug is provided with a remote switch.

[0008]

According to the present invention, commercial AC power is input from an AC outlet 1 to which commercial power is supplied, as shown in the principle configuration diagram of the commercial power battery backup circuit according to the present invention in FIG. AC outlet plug 2 for converting; AC / DC conversion circuit 4 for converting commercial AC power input through the AC outlet plug 2 into a predetermined DC power supply voltage and giving it to a load (device) 8; and the load (device) 8 in parallel with the power supply to 8
Charge a predetermined DC power supply voltage from the / DC conversion circuit 4,
When the DC voltage falls below a predetermined value, the AC / D
In a commercial power supply battery backup circuit comprising a battery circuit 7 for discharging to the load (device) 8 in place of the C conversion circuit 4: Further, when the AC outlet plug 2 is not engaged with the AC outlet 1. There is provided a commercial power supply battery backup circuit provided with a switch circuit 3 which cuts off a discharge path from the battery circuit 7 to the load (device) 8 and thereby stops the discharge operation of the battery circuit 7.

When the switch circuit 3 is incorporated in the AC outlet plug 2 and is constituted by a manual push button switch, the switching state that cuts off the discharge path is locked, and the AC outlet 1 and the AC outlet are connected. An engagement detecting means for automatically detecting the engagement state with the outlet plug 2 and controlling the opening / closing may be provided.

Further, the commercial power source battery backup circuit controls the coupling between the output of the battery circuit 7 and the path from the AC / DC conversion circuit 4 to the load (device) 8 by the switch circuit 3. A discharge circuit 5 is included, or a load disconnection circuit 6 that controls the coupling between the load (device) 8 and its power supply path by the switch circuit 3 is included. The commercial power supply battery backup circuit according to the present invention is applied to general household equipment or commercial equipment using a commercial power supply.

[0011]

According to the present invention, by pulling out the AC outlet plug 2 from the AC plug 1, the battery circuit 7
Is forcibly separated from its discharge path, it is possible to prevent wasteful consumption of battery power when it is obvious that the device is not used. According to the present invention, the discharging function from the battery 7 at the time of power failure of the commercial power source functions as usual, and in addition, the discharging operation of the battery 7 when the AC outlet plug 2 is pulled out is stopped. Discharge control of the battery 7 that clearly distinguishes the two cases becomes possible.

[0012]

FIG. 2 shows a first embodiment of a commercial power source battery backup circuit according to the present invention. In the embodiments of the present invention shown in FIGS. 2 to 6 which will be described later, the same components as those in the conventional example shown in FIG. 8 are designated by the same reference numerals and will not be described further. In FIG. 2, when the commercial power supply is energized, the commercial power is supplied from the AC outlet 11 through the AC plug 12 to the primary side of the AC / DC converter 13, and the AC / DC converter 13 is supplied.
The power converted to DC from the secondary side of the load (device) 1
8 is supplied. At the same time, the battery 15 always connected in parallel with the load is charged through the charging diode D1.

An AC relay (AC relay RL1) 22 for monitoring the input of the commercial power source is connected to the input primary side, and when the input power source is energized, a moving current flows through the AC relay 22. , So that the relay contact (rl1) 20 provided in the secondary side battery discharge circuit 23
Is open, disconnecting the connection between the battery 15 and the load 18.

When the commercial power supply fails or the output of the commercial power supply drops abnormally, no touching current flows through the AC relay 22 and the secondary side relay contact 20 is closed. As a result, the load 18 is passed from the battery 15 through the discharging diode (D2) 17 for passing through the charging current control circuit 16.
Is supplied with power. After that, when the commercial power is restored,
Sensitive current flows through the AC relay 22 again, and the secondary side relay contact 20 is opened. As a result, power is supplied from the AC / DC converter 13 to the load 18 in a steady state.

In the remote switch (SW1) 21 in the discharge circuit 23, the AC plug 12 is connected to the AC outlet 1 regardless of the above-mentioned power failure of the commercial power source or the battery backup operation due to the abnormal reduction of the output voltage.
It is for turning off by detecting the disconnection from 1, and thereby forcibly cutting off the power feeding route from the battery 15 to the load 18.

FIGS. 3 and 4 show an embodiment in which the remote switch 21 is incorporated in the AC plug 12, respectively. The remote switch (SW1) 21 built in the AC plug 12 shown in FIG. 3 and FIG.
This corresponds to a specific example of the remote switch 21 connected in series with the secondary relay contact (rl1) 20 in FIG.

FIG. 3 shows an example (manual example) in which a remote switch (push button type lock switch) 21 is mounted on the upper surface of the AC plug 12. When there is no need to back up, press this switch 21 to lock the remote switch 21 to OFF,
Pull out the C plug 12. Next, when inserting the AC plug 12 into an AC outlet to supply power, the main switch 21 is pressed again to release the OFF state of the remote switch 21.

FIG. 4 shows an example (automatic example) in which a remote switch (push button type micro switch) 21 is mounted on the plug surface of the AC plug 12, and when it is not necessary to make a backup, the AC plug 12 is shown. In order to remove the switch from the AC outlet 11, the protrusion of the microswitch automatically detects it and turns off the main switch 21. On the contrary, when the main plug 12 is inserted into the AC outlet 11, the protrusion is pushed and the main switch 21 is automatically turned on.

When the AC plug 12 with a remote switch according to the present invention is used, the battery backup operation of FIG. 2 does not require the user to back up the load (device) 18, and when the AC plug 12 is unplugged. The remote switch (SW1) 21 is turned off. As a result, the backup power supply path from the battery 15 to the load 18 is forcibly cut off, and wasteful consumption of the battery 15 is prevented.

FIG. 5 shows a second embodiment of the commercial power source battery backup circuit according to the present invention. In this embodiment, the AC (AC) relay 22 in the first embodiment shown in FIG. 2 described above is generally larger in size and more expensive than the DC (DC) relay, so that DC is provided in terms of mounting and economics. This is a circuit configuration using a relay.

In FIG. 5, when the commercial power source is energized, the charging current limiting circuit 16 causes the secondary side charging diode (D
1) Constant current charging of the battery 15 is performed via 19. Secondary output voltage is Zener diode (D3) 27
When the breakdown voltage becomes equal to or higher than, the relay driving transistor (TR1) 24 is turned on, and a sensing current flows in the DC relay (RL1) 25. Therefore, the relay contact (rel) 20 is opened when the commercial power source is energized.

On the other hand, at the time of a power failure of the commercial power supply, the output voltage on the secondary side becomes equal to or lower than the breakdown voltage of the Zener diode 27 and the relay driving transistor 24 is turned off, so that the relay contact 20 of the DC relay 25 is closed. The battery 15 is discharged to the load 18 via the discharge path. Note that the voltage of the battery 15 is generally different during charging and discharging, and is lower during discharging than during charging. Therefore, if the breakdown voltage of the Zener diode 27 is set to a voltage higher than the battery voltage at the time of discharging, the relay driving transistor 24 is not accidentally turned on at the time of discharging, and the discharge path is not cut off.

Next, when the user does not need to back up the load (device) 18 and pulls out the AC plug 12, the remote switch (SW1) 21 is turned off as in the first embodiment. Therefore, the discharge path from the battery 15 to the load 18 is forcibly disconnected. Therefore, when it is not necessary to back up the load 18, useless consumption of the battery can be prevented.

FIG. 6 shows a third embodiment of the commercial power source backup circuit according to the present invention. In the first and second embodiments described above, switching of the charging / discharging circuit was performed by the relay contact, but in this embodiment, the load (device) side is electronically disconnected by using a transistor. .

In FIG. 6, when the commercial power source is energized, the charging current limiting circuit 16 charges the secondary battery 15 with a constant current. In the output state of the secondary side voltage, a voltage obtained by dividing the output voltage by the bleeder resistances (R2) 31 and (R3) 32 is applied to the base of the control transistor (TR2) 30 and thereby the control transistor 30.
Turns on. With the ON output, the base resistance (R
1) A load disconnection transistor (TR
1) 28 is driven, and the load disconnection transistor 28 maintains the ON state in the output state of the secondary side voltage.
During that time, power is supplied from the AC / DC converter 13 to the load 18. Further, at the time of power failure of the commercial power supply, the base of the control transistor 30 is connected to the plus side of the battery 15, so that it remains ON until the battery capacity is exhausted.
Therefore, the load disconnection transistor 28 also remains in the ON state.

Next, when the user does not need to back up the load (device) 18 and disconnects the AC plug 12, the remote switch (SW1) 21 is turned off and the base of the control transistor 30 is the battery 15. Separated from. This turns off the control transistor 30.
As a result, the load disconnection transistor 28 is also OF
Then, the connection with the load 18 is cut off. Therefore, power is not supplied from the battery 15 to the load 18, and the battery 1
It is possible to prevent wasteful consumption of No. 5.

FIG. 7 shows a fourth embodiment of the commercial power source backup circuit according to the present invention. This embodiment is also configured to electronically disconnect the load (device) side by using a transistor as in the third embodiment of FIG. 6 described above. However, it differs from FIG. 6 in that a photothyristor is used for the circuit on the control side.

In FIG. 7, when the commercial power source is energized, the secondary side battery 15 is charged with a constant current by the charging current limiting circuit 16. Since the control transistor (TR2) 30 is turned on as long as the voltage on the secondary side is present, the load disconnecting transistor (TR1) 28 is also kept in the on state during that time, and power is supplied to the load. In addition, the base of the control transistor 30 is the battery 15 even when the commercial power source fails.
Since it is connected to the positive side of the battery, the ON state is maintained until the battery capacity runs out, and during that time, battery backup power is supplied to the load 18 via the load disconnecting transistor 28.

Next, when the user does not need to back up the load (device) 18 and pulls out the AC plug 12, the remote switch (SW1) 21 is turned on, and as a result, the secondary switch is connected. The diode (SSR1-1) 36 side of the photothyristor emits light and the thyristor (SSR-2) 33 side of the photothyristor connected to the base of the control transistor (TR2) 30 is turned on. Therefore, the control transistor 30 is turned off, the load disconnecting transistor 28 is also turned off, and the load 18 is disconnected. Therefore, electric power is not supplied from the battery 15 to the load 18. The light emitting current flowing through the diode 36 of the photothyristor by the battery 15 is a minute current of about several tens of μA.

[0030]

As described above, according to the commercial power supply battery backup circuit using the AC plug with the remote switch according to the present invention, it is possible to determine whether the commercial power supply has a power failure or the AC plug is disconnected from the AC outlet. Therefore, an appropriate battery backup can be supplied to the load (device).

[Brief description of drawings]

FIG. 1 is a block diagram showing a basic principle configuration of a commercial power supply battery backup circuit according to the present invention.

FIG. 2 is a circuit diagram showing a first embodiment of a commercial power supply battery backup circuit according to the present invention.

FIG. 3 is a perspective view showing an embodiment of an AC outlet plug with a remote switch according to the present invention.

FIG. 4 is a perspective view showing another embodiment of an AC outlet plug with a remote switch according to the present invention.

FIG. 5 is a second commercial power source backup circuit according to the present invention.
It is a circuit diagram showing an example of.

FIG. 6 is a third commercial power source backup circuit according to the present invention.
It is a circuit diagram showing an example of.

FIG. 7 is a fourth commercial power source backup circuit according to the present invention.
It is a circuit diagram showing an example of.

FIG. 8 is a diagram showing a configuration example of a conventional commercial power supply battery backup circuit.

[Explanation of symbols]

 11 ... AC outlet 12 ... AC outlet plug 13 ... AC / DC converter 15 ... Battery 16 ... Charging current limiting circuit 18 ... Load 21 ... Remote switch

Claims (8)

[Claims] 1. An AC outlet plug (2) for inputting commercial AC power from an AC outlet (1) to which a commercial power supply is provided, and commercial AC power input through the AC outlet plug (2) is a predetermined DC power supply voltage. Converted to load (equipment)
An AC / DC conversion circuit (4) for giving to (8), and a predetermined DC power supply voltage from the AC / DC conversion circuit (4) is charged in parallel with power supply to the load (device) (8). , The load (equipment) instead of the AC / DC conversion circuit (4) when the DC voltage becomes a predetermined value or less
A commercial power supply battery backup circuit comprising a battery circuit (7) for discharging to (8), further comprising the battery circuit () when the AC outlet plug (2) is not engaged with the AC outlet (1). A commercial power source battery backup circuit, characterized in that a switch circuit (3) is provided to cut off the discharge path from the load circuit (7) to the load (device) (8), thereby stopping the discharge operation of the battery circuit (7). . 2. The commercial power supply battery backup circuit according to claim 1, wherein the switch circuit (3) is incorporated in the AC outlet plug (2). 3. The commercial power supply battery backup circuit according to claim 2, wherein the switch circuit (3) is configured by a manual push-button switch, and a switching state that disconnects the discharge path is locked. 4. The switch circuit (3) has an engagement detection means for automatically detecting an engagement state between the AC outlet (1) and the AC outlet plug (2) to perform opening / closing control. Item 2. A commercial power source battery backup circuit according to item 2. 5. The switch circuit (3) disconnects the output of the battery circuit (7) from a path connecting the AC / DC conversion circuit (4) and the load (device) (8). 1. A commercial power battery backup circuit according to 1. 6. The switch circuit (3) further connects the output of the battery circuit (7) and a path from the AC / DC conversion circuit (4) to the load (device) (8). The commercial power battery backup circuit according to claim 1, including a discharge circuit (5) for controlling the battery. 7. The commercial power supply according to claim 1, further comprising a load disconnection circuit (6) for controlling coupling between the load (equipment) (8) and its power supply path by the switch circuit (3). Battery backup circuit. 8. A general household device or a business device using a commercial power supply including the commercial power supply battery backup circuit according to claim 1. Description: