JPH06292363A - Ac adapter - Google Patents

Abstract

PURPOSE:To reduce the power consumption of an AC adapter supplying commercial AC input from a plug after converting it into a DC voltage instead of a battery to a battery-type equipment when it is not operating and the deterioration of an electrolytic capacitor when the AC adapter is connected to the battery-type equipment operating on a built-in battery. CONSTITUTION:A switch 9 is selected to AC adapter side while it is linked to the connection of a connector 8. When a power switch 13 of a battery-type equipment 2 is turned on, the voltage of the battery 12 energizes a relay 7 via a diode 10 and hence turns on an AC adapter 1. The output voltage of the adapter 1 is slightly higher than the voltage of the battery 12, thus supplying DC voltage from the adapter 1 to the battery-type equipment 2 and at the same time energizing the relay 7 via a diode 11. Then, by turning off the power switch 13, the relay 7 is deenergized and the AC adapter 1 is turned off.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an AC adapter as a power supply device for using a battery-powered device, which operates by itself with a built-in battery as a power supply, as a commercial power supply. In the drawings below, the same reference numerals indicate the same or corresponding parts.

[0002]

2. Description of the Related Art A conventional AC adapter has its plug
In the state of being plugged into the C outlet, the power is always on even if the power switch of the battery-powered device should not be off. As a method for prolonging the life of the electrolytic capacitor built into the AC adapter, in Japanese Utility Model Laid-Open No. 63-172289, a means for turning off the electrolytic capacitor circuit when the power switch of the battery-powered equipment is turned off is proposed. There is.

[0003]

As described above, the conventional A
When the C adapter is plugged into the AC outlet, the power is always ON regardless of whether the switch of the battery-powered device is ON or OFF. Therefore, wasteful power is consumed and heat is generated. It shortens the life of the electrolytic capacitor inside the adapter. Even if only the circuit of the electrolytic capacitor is turned off as in Japanese Utility Model Laid-Open No. 63-172289, heat is generated due to iron loss of the transformer, so that the temperature of the electrolytic capacitor rises and the life of the electrolytic capacitor is affected.

Further, in order to turn off the AC adapter, it is necessary to pull out the AC adapter from the AC outlet, and if the AC adapter is frequently inserted and removed instead of the switch, the outlet and the plug of the AC adapter deteriorate. Therefore, the present invention provides an AC adapter capable of turning on / off the power of the AC adapter in conjunction with turning on / off a switch of a battery-powered device while the AC adapter is still connected to an AC outlet. Is an issue.

[0005]

In order to solve the above-mentioned problems, the AC adapter according to claim 1 has a plug (51 or the like) to be inserted and connected to an AC power outlet, and an AC input through this plug. Power conversion means for generating DC power from the power supply (transformer 26, rectifier 4, electrolytic capacitor 5
Etc.) and a connector for outputting this DC power supply (8 etc.)
Further, the connector is provided with a switching means (switch 9 etc.) for switching such that the built-in battery (12 etc.) is used as a power source when the connector is not connected and the DC power source is used as the power source when the connector is connected. , A battery-powered device having a power switch (13, etc.) for turning on / off the connection between the power supply switched by the switching means and the internal circuit serving as a load of the power supply based on a manual operation (via the contact 131 etc.) An AC adapter (1 or the like) to which (2 or the like) is connected, the opening / closing means (relay 7 or the like) for opening / closing the connection between the plug and the power conversion means, and the battery-operated device connected to the AC adapter. When the power switch is turned on, the opening / closing means is energized by using the battery as the energizing power source to close the connection between the plug and the power converting means, and thereby the DC power source After the startup, this DC power supply is used as an energizing power supply, and an opening / closing control means for deactivating the opening / closing means to open the connection between the plug and the power conversion means when the power switch is turned off is provided. I shall.

According to a second aspect of the present invention, in the AC adapter according to the first aspect, the battery-operated device is closed / opened in conjunction with an on / off operation of the power switch. And the like), and the opening / closing control means uses the battery as an energizing power source through at least the closed contact.

According to a third aspect of the present invention, in the AC adapter according to the second aspect, the opening / closing control means transfers the voltage of the battery or the DC power source from the battery-operated device side to the opening / closing means via the contact. The output line of the DC power source of the AC adapter (electric wire 52,
It should be equipped with an electric wire (such as 54) different from 53).

Further, in the AC adapter according to claim 4, the AC adapter according to claim 2 is a current drop detecting means for detecting that the current supplied to the battery-powered device has fallen below a predetermined value (current detection circuit 14 or the like). ), The switching control means determines that the power switch has been turned off based on the detection of the current drop detection means after the DC power supply has started up, and switches the opening / closing means (current Detector 23,
It should be de-energized (via AND gates 27, 28, OR gate 29, transistor 30, etc.).

According to a fifth aspect of the present invention, in the AC adapter according to the fourth aspect, the switching control means detects the voltage drop detecting means (voltage detection means) for detecting that the voltage of the DC power supply is below a predetermined value. 21 and 22) and the opening / closing means (AND gate 2) based on the detection of the voltage drop detecting means after the DC power supply is turned on.
7, 28, OR gate 29, transistor 30, etc.).

Further, in the AC adapter according to claim 6, the AC adapter according to any one of claims 1 to 5 is:
A switch (3 or the like) for short-circuiting the opening / closing means by a manual operation when necessary is provided.

[0011]

[Function] By using the energy of the battery contained in the battery-powered device and interlocking with the power switch of the battery-powered device so that the power of the AC adapter can be turned ON / OFF, useless power consumption is reduced. Prevention, prolonging the life of the electrolytic capacitor and also allowing the AC adapter to remain plugged into the AC outlet to prevent deterioration of the AC outlet and the plug of the AC adapter.

[0012]

Embodiments of the present invention will be described below with reference to FIGS. FIG. 1 is a circuit diagram showing a configuration as a first embodiment of the present invention. In the figure, 1 is an AC adapter in which a plug 51 is inserted into an outlet (AC outlet) of a commercial AC power supply (not shown) to produce a DC power supply, 2 is operated by a built-in battery 12 by itself, and AC is supplied via a connector 8. When connected to the adapter 1, it is a battery-operated device that operates by the DC power source generated by the AC adapter 1.

Further, in the AC adapter 1, 3 is a manual switch for backup in case of abnormality which is normally turned off, 7
Is a relay for opening and closing the AC power input to the AC adapter 1, 6 is a transformer for converting the voltage of the commercial AC power into an AC voltage according to the DC voltage generated by the AC adapter 1,
Reference numeral 4 is a rectifier for rectifying the output AC voltage of the transformer 6, and 5 is an electrolytic capacitor for smoothing the DC voltage output by the rectifier 4. Further, in the battery-powered device 2, 8 is a connector for coupling the AC adapter 1 and the battery-powered device 2, 9 is interlocked with the connector 8, and supplies power to an internal circuit (not shown) of the battery-powered device 2 with a built-in battery. A switch for switching between the 12 side and the AC adapter 1 side, 13 is a manual power switch for turning on / off the operation of the battery-powered device 2 (that is, power supply to the internal circuit), and 131 and 132 are contacts thereof. Is.

In the example of FIG. 1, the AC adapter 1 and the battery-powered device 2 are connected by three electric wires 52 to 54. Here, two of the electric wires 52 and 53 are power supply wires, and one of the electric wires 54 is for power supply control of the AC adapter 1. Next, the operation of FIG. 1 will be described. As described above, the switch 9 is interlocked with the connector 8, and switches to the battery 12 side when the connector 8 is not connected and to the AC adapter 1 side when the connector 8 is connected. In addition, in FIG. 1, the AC adapter is switched. Therefore, when the connector 8 is not connected, the power switch 13 (contact 131) is turned on / off.
In accordance with the
The power supply to the internal circuit of is turned on / off.

Next, in the state shown in FIG. 1, the power switch 13 is turned on.
In this case, current flows from the battery 12 to the relay 7 in the AC adapter 1 via the diode 10, the contact 132 of the power switch 13, and the electric wire 54, the relay 7 is turned on, and the AC adapter 1 Turns on. Therefore, from the AC adapter 1 to the electric wires 52, 5 to the internal circuit of the battery-powered device 2,
DC power is supplied via 3.

Here, the output voltage of the AC adapter 1 is set to the battery 1
AC adapter 1 is turned on by setting the voltage higher than 2.
From this point of time, the current flowing to the relay 7 is supplied from the AC adapter 1 itself via the diode 11, the current stops flowing to the diode 10, and the supply of electric power from the battery 12 is stopped. When the power switch 13 is turned off, the current flowing through the relay 7 is cut off and the AC adapter 1 is turned off.

The battery 12 is exhausted and the relay 7 is turned on.
When the current necessary for the operation cannot be supplied, and when the battery 12 is not inserted, the switch 3 is turned on, so that the AC adapter 1 is turned on regardless of the power switch 13 like a normal AC adapter. You can also FIG. 2 is a circuit diagram showing the configuration of the second embodiment of the present invention. In the figure, the electric wires connecting the AC adapter 1 and the battery-powered device 2 are only the two electric wires 52 and 53 for power supply, and
A diode 11 in the adapter 1, a current detection circuit 14 for detecting the load current of the AC adapter 1, and a relay 7
A power supply control circuit 15 for controlling the opening and closing of is provided.

The potential of the positive power supply line 52 of the DC output of the AC adapter 1 (in other words, the potential of the output side of the diode 10 of the battery-powered device 2) is input to the terminal V1 of the power supply control circuit 11, and The potential on the anode side of the diode 11 (in other words, the positive electrode potential of the smoothing electrolytic capacitor 5 of the rectification output section of the AC adapter 1) provided in series with the power supply line 52 is input to the terminal V2, and also to the terminal V0. The negative potential of the electrolytic capacitor 5 is input, and the detection output of the current detection circuit 14 is also input to the terminal I.

Next, the operation of FIG. 2 will be described. The switch 9 interlocks with the connector 8, and switches to the battery 11 side when the connector 8 is not connected and to the AC adapter 1 side when the connector 8 is connected. In FIG. 2, it is on the AC adapter side. When the power switch 13 is turned on, the battery 12 is connected to the power control circuit 15 in the AC adapter 1 via the contact point 132, the diode 10 and the power line 52.
Power is supplied through the terminals V1 and V0, the power supply control circuit 15 turns on the relay 7, and the AC adapter 1 is turned on.

By making the output voltage of the AC adapter 1 higher than that of the battery 12, the power supplied to the power supply control circuit 15 from the time when the AC adapter 1 is turned on is AC.
Power is supplied from the adapter 1 itself, current does not flow through the diode 10, and power supply from the battery 12 is stopped. When the power switch 13 is turned off, the current from the AC adapter 1 to the battery-powered device 2 is cut off.

When the power supply control circuit 15 detects that the current from the AC adapter 1 to the battery-powered device 2 is cut off by the signal input from the current detection circuit 14 to the terminal I,
The relay 7 is turned off and the AC adapter 1 is turned off. If the battery 12 is exhausted and the current required to turn on the relay 7 cannot be applied, or if the battery 12 is not present, turn on the switch 3 to turn on the normal A
As with the C adapter, the AC adapter 1 can be turned on regardless of the power switch 13.

FIG. 3 shows the configuration of the power supply control circuit 15. In the figure, 21 and 22 are voltage detectors, 23 is a current detector, 25 is a resistor, 26 is a NOT gate, 27 and 2
8 is an AND gate, 29 is an OR gate, 30 is a transistor, and 31 is a delay circuit. FIG. 4 is a time chart showing changes in the potential of each part in FIG. 3, and (1) to (12) show timings in FIG. Next, the operation of FIG. 3 will be described with reference to FIGS. When the power switch 13 of the battery-powered device 2 of FIG. 2 is turned on, when the battery 12 supplies power to the power control circuit 15 via its terminals V1 and V0, and at the same time, the voltage of the terminal V1 becomes a certain voltage or more. , The output of the voltage detector 21 becomes H [(1)]. At that time, the relay 7 is in the OFF state and the potential of the terminal V2 is zero, so the output of the voltage detector 22 is L [(2)]. Therefore, the output of the AND gate 27 becomes H [(3)], and the output of the OR gate 29 becomes H [(4)], the transistor 30 is turned on, the relay 7 is also turned on, and the AC adapter 1 is turned on. Becomes

When the AC adapter is turned on, a voltage is generated at the terminal V2 and power is supplied to the battery-powered device 2, so a current flows, a signal is generated at the terminal I, and the outputs of the voltage detector 22 and the current detector 23 are generated. It becomes H [(5), (6)]. Since the outputs of the voltage detectors 21 and 22 and the current detector 23 are H at this point, the output of the AND gate 28 becomes H [(7)]. On the other hand, the output of the AND gate 27 becomes L after the delay time of the delay circuit 31 elapses because the output of the voltage detector 22 becomes H [(8)].

Next, when the power switch 13 of FIG. 2 is turned off, the supply of electromotive force to the battery-powered device 2 is stopped, and the current stops flowing, so that the signal at the terminal I disappears and the current detector 2
The output of 3 becomes L [(9)]. Therefore AND gate 2
The output of 8 becomes L [(10)]. Therefore, since the output of the AND gate 27 has already become L, the OR gate 29
Output is also L [(11)], and the transistor 30 is O
The FF state is set, the relay is turned off, and the AC adapter is turned off. When the AC adapter is turned off, the voltages V1 and V2 disappear, and the outputs of the voltage detectors 21 and 22 become L [(12)].

Further, in the present control circuit 15, when an abnormality occurs in the battery-powered device 2 and the output of the AC adapter is short-circuited, the potentials of the terminals V1 and V2 are significantly lowered, so that the voltage detector 2
The outputs of 1 and 22 are L, and the AC adapter is OFF. Although the transformer 6 and the rectifier 4 are used in this embodiment, this portion may be used as a switching regulator type power supply device.

[0026]

According to the present invention, the energy of the battery contained in the battery-powered device is used to turn on / off the power of the AC adapter in conjunction with the power switch of the battery-powered device. It is possible to prevent unnecessary power consumption of the AC adapter, extend the life of the electrolytic capacitor, and prevent deterioration of the AC outlet and the plug of the AC adapter. Further, the AC adapter can be turned off even when an abnormality occurs in the battery-powered device and the output of the AC adapter is short-circuited.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a configuration as a first embodiment of the present invention.

FIG. 2 is a circuit diagram showing a configuration as a second embodiment of the present invention.

FIG. 3 is a circuit diagram showing an internal configuration of the voltage control circuit of FIG.

FIG. 4 is a time chart for explaining the operation of FIG.

[Explanation of symbols]

 1 AC Adapter 2 Battery Equipment 3 Switch 4 Rectifier 5 Electrolytic Capacitor 6 Transformer 7 Relay 8 Connector 9 Switch 10 Diode 11 Diode 12 Battery 13 Power Switch 14 Current Detection Circuit 15 Power Control Circuit 21 Voltage Detector 22 Voltage Detector 23 Current Detection Device 25 Resistor 26 NOT gate 27 AND gate 28 AND gate 29 OR gate 30 Transistor 31 Delay circuit 51 Plug 52 Electric wire 53 Electric wire 54 Electric wire

Claims (6)

[Claims] 1. A plug, which is inserted and connected to an outlet of an AC power supply, a power conversion unit for generating a DC power supply from the AC power supply input through the plug, and a connector for outputting the DC power supply. The connector has switching means for switching such that the built-in battery is used as a power source when the connector is not connected and the DC power source is used as the power source when the connector is connected, the power source switched by the switching means, and the load of the power source. An AC adapter to which a battery-powered device having a power switch for turning on / off a connection with an internal circuit according to a manual operation is connected, the opening / closing means opening / closing the connection between the plug and the power conversion means, When the power switch of the battery-powered device connected to the AC adapter is turned on, the battery is used as a power source to urge the opening / closing means to activate the power source. After the direct current has risen by closing the connection between the plug and the power conversion means, this direct current power source is used as an activating power source, and when the power switch is turned off, the opening / closing means is deactivated and the plug is connected. And an opening / closing control means for opening the connection between the power conversion means and the power conversion means. 2. The AC adapter according to claim 1, wherein the battery-operated device includes contacts that are closed / opened in association with an on / off operation of the power switch, and the opening / closing control means is at least An AC adapter which uses the battery as an energizing power source via the closed contact. 3. The AC adapter according to claim 2,
The opening / closing control means includes an electric wire different from the output line of the DC power supply of the AC adapter, which supplies the voltage of the battery or the DC power supply from the battery-powered device side to the opening / closing means via the contact as an urging power supply. A which is characterized by
C adapter. 4. The AC adapter according to claim 2, further comprising a current drop detecting means for detecting that a current supplied to the battery-powered equipment is below a predetermined value, and the opening / closing control means has the DC power supply turned on. An AC adapter, which determines that the power switch has been turned off based on the detection of the current drop detecting means after climbing and deactivates the opening / closing means as described above. 5. The AC adapter according to claim 4, wherein the opening / closing control means includes a voltage drop detection means for detecting that the voltage of the DC power supply is below a predetermined value, and the DC power supply is turned on. An AC adapter for deactivating the opening / closing means based on the detection of the voltage drop detecting means after that. 6. The AC adapter according to claim 1, further comprising a switch that short-circuits the opening / closing means by manual operation when necessary.