JP3244725B2 - Rechargeable electrical equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rechargeable electric device, and more particularly to a device for forcibly turning off a load drive during charging.

[0002]

2. Description of the Related Art Heretofore, portable battery-applied equipment which incorporates a rechargeable battery and drives a load such as a motor with the battery has been used. In such a device, when the AC power is turned on while the load switch is turned on (while the switch is turned on), the load suddenly starts to be driven, or charging is sufficiently performed because the load is driven. There was a problem that there is no. For this reason, a mechanical switch called a plug switch, which is mechanically linked to the charging plug, is connected between the battery and the load, and when an AC power supply is connected to the charging plug, the plug switch forcibly connects the battery and the load. In this case, the battery was cut off so that normal charging could be performed.

FIG. 4 shows a circuit diagram of a conventional rechargeable electric device provided with such a plug switch. When the load switch MSW is turned on, a current is supplied from the battery B to the load M, and the load M is driven. When the capacity of the battery B decreases and the AC plug PG is connected to an AC power supply, the battery is charged by a predetermined direct current rectified by the charging circuit. The AC plug PG is configured to turn on and off a plug switch PSW interposed between the battery B and the load M in mechanical linkage with an attachment / detachment operation with an AC power supply. The plug switch PSW is normally closed, and when an AC power supply is connected to the AC plug PG, the plug switch PSW
W is turned off to shut off the load circuit.

[0004]

However, since the plug switch PSW needs to be mechanically linked to the operation of the charging plug, the plug switch PSW must be disposed very close to the AC plug PG. Since the battery B, the load M, or the load switch MSW for turning on / off the load drive in the device is generally provided at a required position in consideration of the availability of the device distant from the input side, wiring is connected between the two by connecting the wiring. Therefore, it is difficult to design a circuit in the device and reduce the size of the device.

[0005] The present invention has been made in view of the above,
By electrically detecting that the charging plug is connected to the AC power source, the detection signal is used to forcibly turn off the battery and the load. It is an object of the present invention to provide a rechargeable electric device that eliminates difficulty in downsizing the device.

[0006]

SUMMARY OF THE INVENTION The present invention provides a rechargeable battery connected to a charging plug, a load driven by the battery, and detecting means for detecting that the charging plug is connected to an AC power supply. Switching means connected between the battery and the load, a charging circuit for turning off the switching means by a detection signal indicating the start of charging from the detection means, and a switching circuit connected in parallel with the battery to turn on the switching means. When the battery capacity is reduced to a predetermined amount as a result of driving the load, the driving state of the load is changed and the remaining capacity is forcibly used by receiving an operation on a switch connected in series to the load. And a reserve power circuit configured to cause the reserve power circuit to keep the switching means off during charging. It is obtained by the.

[0007]

According to the present invention, when the AC power is connected to the charging plug and charging is started, the connection of the AC power is detected by the detecting means, and the detection signal is guided to the switching means by the charging circuit. Thus, while the reserved power circuit tries to turn on the switching means, the battery and the load are forcibly shut off (off).

[0008]

FIG. 1 is a circuit diagram showing a first embodiment of a rechargeable electric device according to the present invention. In the figure, reference numeral 1 denotes an AC power supply such as a commercial power supply, and a charging plug 2 on the rechargeable electric device side.
a, 2b. B is a rechargeable battery in which one or a plurality of batteries are connected in series to obtain a required level of voltage. Charging plug 2a, 2b
Is provided with a charging circuit 3. This charging circuit 3
The battery B is rectified by the DC charging current obtained by rectifying the AC current supplied from the AC power supply 1 through the charging plugs 2a and 2b.
Although not shown in the figure, full charge control is performed by charging time, ΔT control based on battery rising temperature, and ΔV control based on battery voltage rising characteristics. The charging circuit 3 includes a charging plug 2
a, 2b is connected to an AC power supply, when an AC is input, and to output a voltage signal of a predetermined high level from the terminal P _0.

[0009] load circuit comprises a series circuit consisting of transistors Q _1, load 4 such as a motor serving as a switching means, connected in parallel to the battery B. R ₂ is a base resistance of the transistor Q ₁ , and SW is a low power main switch for switching the driving of the load 4 on and off. Also,
Between the between terminal P ₀ of the charging circuit 3 the transistor Q ₁ base and resistor R1 diode D ₁ and the current limiting oriented in the forward direction are connected in series.

Next, the operation of the above circuit configuration will be described. Battery B is charged, and charging plugs 2a and 2b are AC
After being detached from the power supply 1, the main switch SW is turned on, the base voltage of the transistor Q ₁ is lowered, the transistor Q ₁ is turned on. This by turning on the transistor Q ₁ is between 4 and load cell B are short-circuited, the load the load current from the battery B is supplied to the load 4 4 is driven. Turning off the main switch SW, the transistor Q ₁ is turned off, the supply of load current to the load 4 is stopped.

When the battery capacity is consumed, charging is subsequently performed. At this time, in a state where the main switch SW is turned off, charging plug 2a, when the AC power source 1 is connected to 2b, the transistor Q ₁ by the high-level signal output from the terminal P ₀ of the charging circuit 3 is still off Maintain the state as described above.

On the other hand, when the AC power supply 1 is connected to the charging plugs 2a, 2b while the main switch SW is kept on, the battery voltage increases due to the charging operation. However, to maintain the state transistor Q ₁ is a high level signal is output which is the still off from the terminal P ₀ of the charging circuit 3, never power charged in the battery B is supplied to the load 4 side .

FIG. 2 shows a second example of the rechargeable electric device according to the present invention.
FIG. 3 is a circuit diagram showing an example of the embodiment. In the figure, FIG.
Those assigned the same numbers as have the same functions.

In this rechargeable electric apparatus, a main switch SW and a relay switch 5 as a switching means are connected in series with a load 4. That is, the relay switch 5 is a normally closed switch composed of the relay coil 51 and the switch 52. When a current flows through the relay coil 51, the switch 52 is turned off, that is, opened. Both ends of the relay coil 51 are connected between the terminal P ₀ of the charging circuit 3 and the negative electrode of the battery B via a current limiting resistor R ₁ .

Next, the operation will be described. When the main switch SW is turned on after the battery B is charged and the charging plugs 2a and 2b are disconnected from the AC power supply 1, the battery B and the load 4 are short-circuited, and the load current is supplied from the battery B to the load 4. On the other hand, when the main switch SW is turned off, the connection between the battery B and the load 4 is cut off.

At the time of charging, AC is connected to charging plugs 2a and 2b.
When the power supply 1 is connected, the high-level signal output from the terminal P ₀ of the charging circuit 3 activates the relay coil 51 to turn off the switch 52. Therefore, the main switch S
Regardless of the on / off state of W, the electric power charged in the battery B is not supplied to the load 4 side.

FIG. 3 shows a third example of the rechargeable electric device according to the present invention.
FIG. 3 is a circuit diagram showing an example of the embodiment. In the figure, FIG.
Those assigned the same numbers as have the same functions.

In this rechargeable electric device, a reserve power circuit 6 is provided in parallel with the battery B. Q ₂ is a switching transistor connected in series to the load 4, and its base terminal is connected to the control signal output terminal of the reserve power circuit 6. The reserve power circuit 6 detects the battery capacity from the battery voltage, and when the battery capacity reaches, for example, a preset remaining usage time or remaining usage count,
Changing the transistor Q ₂ is lowered by a predetermined level the output level of the control signal output terminal from the predetermined high level to inform it to the user in a semi-conducting, that is, so as to give a change to the drive state of the load 4. For example, when the load 4 is a motor, the number of rotations of the motor is reduced by a required amount. At this time, the user may be notified using a display unit or the like. Also,
In this electrical equipment, in addition to the main switch SW to the load 4 are connected in series, the sub-switch SW ₁ is connected between the emitter-collector of the transistor Q _2. The sub switch SW ₁ when the remaining capacity of the battery B as described above is lowered to a predetermined value, is used to directly force the use of the remaining capacity.

Q ₃ is connected between the base and the emitter of the transistor Q ₂ , and its base is connected to the terminal P _{0 of the} charging circuit 3.
It is connected transistors via a current limiting resistor R ₁ in. The transistor Q ₃ are turned on when a high-level signal from the terminal P ₀ of the charging circuit 3 is output, it is to turn off the transistor Q _2.

Next, the operation will be described. When the main switch SW is turned on after the battery B is charged and the charging plugs 2a and 2b are disconnected from the AC power supply 1, a high-level signal is output from the control signal output terminal of the reserve power circuit 6, and the high-level signal is output. Transistor Q
₂ turns on. At this time, the output signal from the terminal P ₀ is not sent. This by turning on the transistor Q ₂ is between 4 and load cell B are short-circuited, the load the load current from the battery B is supplied to the load 4 4 is driven. Turning off the main switch SW, the transistor Q ₁ is turned off, the supply of load current to the load 4 is stopped.

When the battery capacity is consumed and the remaining amount decreases to a predetermined level, the reserve power circuit 6 detects this and reduces the high level of the control signal output terminal to a required level. The driving state of the load 4 is changed by this level reduction. When subsequent use by the user, when the sub-switch SW ₁ is turned on, driving with full power of the load 4 by a predetermined remaining number of uses or remaining use time is reproduced.

When the battery capacity is consumed in this way, charging is subsequently performed. At this time, in a state where the main switch SW is turned off, charging plug 2a, when the AC power source 1 is connected to 2b, the transistor Q ₃ is turned on by the high level signal output from the terminal P ₀ of the charging circuit 3 This turns off the transistor Q ₂ completely, and shuts off the battery B and the load 4.

On the other hand, when the AC power supply 1 is connected to the charging plugs 2a and 2b while the main switch SW is kept on, the battery voltage increases due to the charging operation. In this case, the reserve power circuit 6 to output a high level signal to the control signal output terminal in accordance with the increase of the battery voltage, i.e. operates to turn on the transistor Q _2.
However, charging the high-level signal output from the terminal P ₀ of the circuit third transistor Q ₃ is turned off, for holding completely turn off transistor Q _2, supplied to the power load 4 side charging battery B It will not be done.

[0024]

As described above, according to the present invention,
Detecting that the charging plug of the rechargeable electric device is connected to the AC power source, the detection signal is used to forcibly switch the switching means connected between the battery and the load even in the configuration in which the reserve power circuit is provided. In addition, there is no need to perform switching control using a mechanically interlocking plug switch as in the prior art, which eliminates restrictions on the arrangement position, thereby facilitating circuit mounting design, and furthermore, as a whole of electrical equipment. Can be reduced in size.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a first embodiment of a rechargeable electric device according to the present invention.

FIG. 2 is a circuit diagram showing a second embodiment of the rechargeable electric device according to the present invention.

FIG. 3 is a circuit diagram showing a third embodiment of the rechargeable electric device according to the present invention.

FIG. 4 is a circuit diagram of a conventional rechargeable electric device provided with a plug switch.

[Reference Numerals] 1 AC power 2a, 2b charging plug 3 charging circuit 4 load 5 cell to Q ₁ relay switch 6 reserve power circuit B rechargeable, Q ₂ transistor Q ₃ transistor SW main switch SW ₁ sub-switch P ₀ pin

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) H02J ^7/ 00-7/38

Claims (1)

(57) [Claims] 1. A rechargeable battery connected to a charging plug, a load driven by the battery, and a charging plug connected to an AC
Detecting means for detecting that it has been connected to a power source, a charging circuit for turning off a switching means connected between the load and the battery, the switching means by the detection signal indicating the start of charging from the top Symbol detection means, Connected in parallel with the above battery
And the load was driven by turning on the switching means.
As a result, when the battery capacity drops to the preset amount,
Change the drive state of the load at
Remaining capacity is forcibly received by operation of switches connected in series
With a reserved power circuit adapted to be used,
The charging circuit is connected to the reserve power circuit during charging.
To keep the switching means off.
A rechargeable electric device, characterized in that: