JPS59209067A - Electric razor - Google Patents

Abstract

PURPOSE:To reduce the power consumption by stopping an oscillator when the charging level of a storage battery reaches a set level or higher. CONSTITUTION:A full-wave rectifier 22 and a smoothing condenser 23 are connected to an AC power source 21 to for a rectifying circuit 24, and 1-element inverter 30 is connected as an oscillator. The output of the inverter 30 is connected through the secondary winding of a transformer 29 and a rectifier of a diode 31 to a storage battery 32. A motor 34 for driving a razor is connected through a switch 33 to the battery 32, and a resistance voltage divider 37 is connected in parallel. A transistor 28 of the inverter 30 is reversely biased through an N-P-N-P transistor 38 with the voltage, and when the charging level of the battery 32 rises over the normal level, the oscillation of the inverter 30 is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] This invention relates to an improvement in an electric shaver that can be used with both an AC power source and a storage battery.

[Technical background of the invention and its problems]

Conventionally, in this type of electric shaver, as shown in FIG. 1, a DC converter circuit 4 consisting of a full-wave rectifier circuit 2 and a smoothing capacitor 3 is connected to an AC power supply l, and a transistor 5 is connected to the output terminal of the DC converter circuit 4. , a single-stone inverter circuit 7 consisting of a transformer 6, etc. is connected, a storage battery 9 is connected to the output end of the inverter circuit 7 via a rectifying diode 8, and a razor drive circuit is connected to the storage battery 9 via a switch 10. It is known that a motor 11 and a bypass circuit 12 each having a plurality of diodes connected in series are connected to each other.

In this device, when the switch 10 is turned on while the storage battery 9 is fully charged, the motor 11 operates and the bypass circuit 12 bypasses the current to suppress the voltage rise of the storage battery 9. to do. However, since this circuit only bypasses the current using a bypass circuit, the inverter circuit 1 constantly oscillates and has the drawback of increasing power consumption. Furthermore, when operating with the storage battery 9, a current of several tens of milliamperes flows through the bypass circuit 12, resulting in a shortening of the discharge time of the storage battery 9.

[Purpose of the invention]

This invention has been made to eliminate these drawbacks, and provides an electric shaver that can reduce the power consumption of the oscillation circuit when used with alternating current, and can lengthen the discharge time when used with a storage battery. The purpose is to

[Summary of the invention]

This invention connects a resistive voltage divider circuit in parallel to the razor drive motor, and when the charge level of the storage battery exceeds the normal level and the voltage level of the voltage divider circuit reaches a set level or higher when the switch is turned on, the transistor becomes conductive. This is to stop the oscillation operation of the oscillation circuit.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

An input end of a full-wave rectifier circuit 22 is connected to an AC power supply 21 . A smoothing capacitor 2 is connected to the output end of the full-wave rectifier circuit 22.
3 are connected to form a direct current converting circuit j4. The smoothing capacitor zsI resistor voltage divider circuit 25, capacitor 26,
27, a single-stone inverter circuit 30 as an oscillation circuit consisting of an NPN transistor 28 and a transformer 29 is connected. A storage battery 32 is connected to the output end of the inverter circuit 30, that is, the secondary winding of the transformer 29, via a diode 31 as a rectifier circuit. Note that the emitter of the transistor 28 in the inverter circuit 30 is connected to the negative terminal side of the output terminal of the full-wave rectifier circuit z2 and to the transformer 2.
It is connected to the connection point between the secondary winding 90 and the positive electrode side of the storage battery 32. A razor drive motor 34 is connected to the storage battery 32 via a switch 33, and a resistor 3 is connected to the motor 34.
A resistive voltage divider circuit 31 formed by connecting 5 and 3fj in series is connected in parallel. NP at the connection point of the resistors 35 and 36
The base of N-type transistor 38 is connected.

the transistor 38 has its collector connected to the base of the transistor 28 in the inverter circuit 30;
Its emitter is connected to the negative electrode side of the storage battery 32. The transistor 38 is set to be conductive at the voltage dividing level of the voltage dividing circuit 37 when the charge level of the storage battery 32 rises above a normal level.

In such a configuration, when connected to the AC power source 21, the inverter circuit 30 oscillates, and the storage battery 32 is charged with the output of the inverter circuit 30. In this state, switch 33
When the power is turned on, the motor 34 operates. During this operation, the charge to the storage battery 32 may rise above the normal level, and at the same time the resistor 35.3 of the resistor voltage divider circuit 37
6 becomes equal to or higher than the set level, and the transistor 3s becomes conductive. As a result, a reverse bias is applied to the transistor 28 of the inverter circuit 30, and the oscillation of the inverter circuit 30 is stopped. This state is maintained until the charge level of the storage battery 32 falls below the normal level.

In this manner, when the AC power supply 21 is used for operation, the oscillation operation of the inverter circuit 30 is stopped when the charge level of the storage battery 32 reaches a normal level or higher, so power consumption in the inverter circuit can be kept low.

Further, when the AC power source 21 is disconnected and the switch 33 is turned on, the motor 34 is supplied with power from the storage battery 32 and operates. At this time, since the resistance value of the resistive voltage divider circuit 37 is relatively large, a very large current does not flow, and the discharge time of the storage battery 32 is not significantly affected. Therefore, the discharge time can be maintained for a sufficiently long time.

Incidentally, in the above-mentioned embodiments, a single-stone inverter circuit was used as the oscillation circuit, but it is needless to say that the present invention is not limited to this.

〔Effect of the invention〕

As detailed above, according to the present invention, the electric shaver can reduce the power consumption of the oscillation circuit when used with an AC power supply, and can extend the discharge time of the storage battery when used with a storage battery. It is possible to provide

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing a conventional example, and FIG. 2 is a circuit diagram showing an embodiment of the present invention. 2I... AC power supply, 24... DC converter circuit, 30...
・Inverter circuit, 31... Rectifier diode, 32
0.・Storage battery, 33... Switch, 34... Razor drive motor, 37... Resistance voltage divider circuit, 38...
NPN transistor.

Claims (1)

[Claims] Alternating current? a DC conversion circuit that is connected to a source and outputs a DC voltage, an excavation circuit that is connected to this DC conversion circuit and outputs AC by excavation, and a storage battery that is connected to the output end of this oscillation circuit via a rectifier circuit. When the razor drive motor 7 is connected via this storage battery switch and the resistor voltage divider circuit is connected in parallel to this motor, the voltage level of this resistor voltage divider circuit reaches a preset level or higher. An electric shaver comprising: a transistor that is conductive and inhibits the oscillation operation of the oscillation circuit.