JPH0834675B2 - Charger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a charging device used for charging and an alternating current drive type electric shaver, and more particularly to a configuration of a charging circuit portion thereof.

(B) Conventional technology As disclosed in, for example, Japanese Patent Publication No. 55-33270, a conventional power conversion circuit includes a primary winding of a transformer between one main electrode of a transformer driving transistor and a power supply terminal. Is connected, the base of the transformer driving transistor is connected to a resistor for supplying a base current, and is connected to the feedback winding of the transformer through a capacitor, and a secondary side of the transformer. Rectifying means connected to the winding, detecting means for detecting when the output of the rectifying means exceeds a predetermined value, a light emitting element that emits light at the output of the detecting means, and In a power conversion circuit consisting of a light receiving element that cuts off the transformer driving transistor, between the other main electrode of the transformer driving transistor and the base,
A control circuit unit for directing the transformer driving transistor in a shutoff direction when the current flowing through the other main electrode of the transformer driving transistor reaches a predetermined value, and the output of the light receiving element is the control circuit; It is connected to operate the section. According to such a technique, the primary side and the secondary side of the transformer can be insulated by the photocoupler, and the power of the primary side can be supplied to the secondary side with reduced power consumption and always stable. . However, in the case of battery charge display, it is also necessary to adjust the output current during rapid charging and trickle charging, and simply connecting the charging battery to the above circuit will affect the output current when driving such a load. There was a problem in that the current could not be adjusted without giving.

(C) Problem to be Solved by the Invention The problem to be solved by the present invention is to drive a load by a rechargeable battery and to directly drive the load with a commercial AC rectified output. It is to insulate the secondary side from the secondary side, and to clearly distinguish the output power value during rapid charging, trickle charging, and load driving. Further, it is also an object to compensate for a decrease in the battery voltage due to discharge when the load is AC-driven.

(D) Means for Solving the Problems A pulse transformer that connects a switching transistor to a primary coil, a control transistor that controls the base current of the switching transistor, and a base current limit on the base of the control transistor, respectively. Light receiving elements of a plurality of photocouplers connected in parallel via a resistor for resistance, a rechargeable battery connected to the secondary coil of the pulse transformer via a first rectifier, and a rechargeable battery connected to the batteries via a switching switch. And a light emitting element of a plurality of photocouplers connected in parallel to the battery via a load, a secondary coil of the pulse transformer through a second rectifier in parallel with the first rectifier, and one light emitting element. Current limiting resistor connected through a transistor for driving, and the secondary coil of the pulse transformer connected for adjustment A charging device comprising a timer circuit for controlling a transistor, and connecting a capacitor for lighting the light emitting element of the photocoupler in parallel with the light emitting element of the photocoupler when the switching switch is turned off.

(E) Action The light emitting element of the photocoupler connected to the secondary side of the pulse transformer is rendered conductive during rapid charging, trickle charging and driving of a load, and the pulse transformer 1 is connected in response to conduction of the light emitting element. The light receiving element of the photocoupler connected to the next side is turned on to control the control transistor, thereby controlling the conduction period of the switching transistor.

Then, before the load is used, the light emitting element of the photocoupler is turned on by the discharge of the capacitor, the light receiving element of the photocoupler is turned on to increase the secondary output of the pulse transformer, and the load can be used for the battery whose capacity has decreased due to the discharge. Charge quickly to the extent.

(F) Embodiment Hereinafter, a charging device of the present invention will be described in detail with reference to an embodiment circuit diagram of the drawings.

In the implementation circuit diagram of Fig. 1, (IN) is 100V, 50 / 60H.
A power input terminal connectable to a commercial AC power supply of z, (BD) is a bridge rectifier that converts the AC input to the input terminal (IN) into DC, and becomes a DC power, (TR) is the rectifier on the primary side (BD) is a pulse transformer for an inverter that inputs the output of (BD) and induces a high frequency alternating current on the secondary side. (B) is a nickel
It is a cadmium rechargeable battery.

The output of the rectifier (BD) is smoothed by a smoothing capacitor (C1) connected to it, and the primary coil (PN) of the transformer (TR), the oscillation transistor (Q1) and the resistor (R1).
Is connected to the rectifier (BD).
The base terminal of the transistor (Q1) is a starting resistor (R9)
Is connected to the center tap of the feedback coil (CN) of the pulse transformer (TR) via the oscillator circuit (TM), and its emitter terminal is also connected to one end of the feedback coil (CN).

(R4) and (R5) are resistors that are connected in parallel with a capacitor (C2) connected between both ends of the feedback coil (CN) to form a voltage dividing circuit, and the voltage dividing point (b) is the transistor. It is connected to the base of a control transistor (Q2) which is formed by connecting a main current circuit to the base bias circuit of (Q1). The emitter terminal of the transistor (Q2) is connected to one end of the feedback coil (CN) via the output adjusting diode (D1). (IPC1) (IP
C2) is the current limiting resistance (R2) (R3) together with the resistance (R5)
Is a photo-coupler of a photo-coupler connected in parallel with, and adjusts the voltage at the voltage dividing point (b) by causing a current to flow through resistors (R2) and (R3) due to conduction of each photo-receiver (IPC1) (IPC2). It is for.

Next, a rectifying diode (D2) and a diode (D6) are branched and connected in parallel to each other at one output terminal of the secondary coil (SN) of the transformer (TR), and smoothing capacitors (C3) and (C4) are respectively connected. ) Is connected and the cathode side of one diode (D2) is connected to the positive terminal of the battery (B), and the cathode side of the other diode (D3) is connected to the input terminal (Vcc) of the timer circuit (TM). It is connected and supplies power, and the timer circuit (T
It is connected to the operating terminal (e) of M).

A switching switch (SW1) having a terminal of is connected to the negative electrode side of the battery (B), and a motor (M) as a load is connected to the battery (B) via the switching switch (SW1). It is connected.

(OPC1) and (OPC2) form a series circuit in parallel with each other via resistors (R6) and (R7) for limiting power supply and backflow prevention diodes (D4) and (D5), and the diode (D3) and the switching switch (SW1). ) Is a light emitting element of a photo coupler inserted between the terminal and the terminal.

The output terminal (d) of the timer circuit (TM) is connected to the base terminal of the adjusting transistor (Q3), the collector terminal of this transistor (Q3) is connected to the light emitting element (OPC2), and its emitter terminal is Terminals of the switching switch (SW1) and battery output current control resistor (R
8) is connected to the terminals at the same time. The negative electrode of the battery (B) is connected to the terminal of the switching switch (SW1), the negative electrode of the motor (M) is simultaneously connected to the terminal and the terminal, and the secondary coil (SN) of the pulse transformer (TR) is connected. The other output terminal is connected to the terminal and the terminal at the same time.

The operation of the charging device having the above configuration will be described below.

When the switching switch (SW1) is slid to the position C and the terminals ,, are short-circuited, the output from the battery (B) is directly applied to the motor (M).
Rotates at high speed. Also, switch the switch (SW1) to B
When the terminals are short-circuited by sliding to the position of, the output from the battery (B) is applied to the motor (M) through the resistor (R8), so the motor (M) is rotationally driven at a low speed. . Further, when the switching switch (SW1) is slid to the position A and the terminals are short-circuited with each other, if commercial alternating current is supplied to the input terminal (IN), the battery is output by the secondary side output of the pulse transformer (TR). Although (B) is charged, the motor (M) is stopped. However, even when the switching switch (SW1) is at the positions B and C, if the commercial AC is connected to the input terminal (IN), the motor (M) is driven by the commercial AC and the battery (B) is charged by floating charging. To be done.

By the way, when the switching switch (SW1) is at the B and C positions and commercial AC is input, the light emitting element (OPC1) (OPC2) of the photo coupler has a diode (D3) and a resistor (R6) or (R7), a diode. A current flows through (D4) or (D5), and the light emitting elements (OPC1) (OPC2) light up. Then, the light receiving elements (IPC1) (IPC2) of the photocoupler become conductive, the resistors (R2), (R3), (R5) become parallel, and the base voltage of the transistor (Q2) decreases. As a result, the base current of the transistor (Q1) increases, the saturation voltage of the transistor (Q1) increases, and the pulse transformer (T1)
The current flowing in the R) primary coil (PN) increases. As a result, the current output from the secondary coil (SN) increases.
Therefore, a large output can be supplied to the motor (M) regardless of the resistance (R8). The current path at this time is the secondary coil (SN) → diode (D2) → motor (M) → terminal → terminal or → secondary coil (SN).

In addition, the switch (SW
When 1) is in the A position, the photocoupler (IPC1) (1PC2) of the photocoupler does not normally conduct, and the transistor (Q2)
Since the base voltage of is high and the collector saturation current is large, the collector current of the transistor (Q1) decreases and only a small current flows through the primary coil (PN) of the pulse transformer (TR). And the secondary coil (SN) of the pulse transformer (TR)
A minute current flows through the battery, and the battery (B) is in a trickle (always) charged state. When the switch (SW2) is opened in this state, the timer circuit (TM) operates, and at the same time, the output terminal (d) of the timer circuit (TM) becomes "High" output and the transistor (Q3) becomes conductive. Therefore, only the light emitting element (OPC2) of the photocoupler lights up, the light receiving element (IPC2) becomes conductive, the resistors (R3) and (R5) become parallel, and the base voltage of the transistor (Q2) drives the motor (M). The intermediate value between time and trickle charge is taken, and the rapid charging current (large current) from the secondary coil (SN) of the pulse transformer (TR) to the battery (B).
Is supplied. This timer circuit (TM) is a switch (SW
The output terminal (d) becomes "Low" output after a lapse of a fixed time after 2) is closed, and returns to the trickle charge state.

The lighting of the light emitting elements (OPC1) (OPC2) can display the state of the charging device at that time.

Next, FIG. 2 shows another embodiment in which the main part is common to FIG. 1, except that the light emitting elements (OPC1) (OPC1 of FIG.
2) A capacitor (C5) and a resistor (R10) are connected in parallel with the resistor (R10) and a diode (D).
4) Connect (D5) to the terminal of the switch (SW1), connect the resistor (R8) to the negative pole of the motor (M), and switch (SW1).
Connected to the emitter terminal of the transistor (Q3) via the terminals of and, and the connection point of the light emitting element (OPC1) and diode (D4) is connected to the terminal of the switching switch (SW1), and the negative electrode of the battery (B). It is connected to the terminal of the terminal switching switch (SW1) and the secondary coil (SN).

Switching switch (SW1) without commercial AC in this example
When A is moved to the positions A, B, and C, it is the same as the example of FIG.

When commercial AC is input, switch (SW
When 1) is in the C position, the terminals of the light emitting elements (OPC1) (OPC2) are short-circuited, and the light is turned on, and the light receiving elements (IPC1) (IPC2) become conductive and the oscillation output of the pulse transformer (TR). Is large and the motor (M) is strongly driven. At this time, the capacitor (C5) is charged at the same time. If the switching switch (SW1) is in the B position, the light emitting element (OPC2) is turned off and one light emitting element (OPC1) is turned on via the terminal →, but the oscillation output of the pulse transformer (TR) is slightly smaller. , The motor (M) is weakly driven because the resistor (R8) is inserted in series.

Further, when the switching switch (SW1) is at the position A, both the light emitting elements (OPC1) (OPC2) are normally off, and the battery (B) is trickle charged by the small output of the pulse transformer (TR).

Now, the motor (M) and battery (B) are switched
1), so the changeover switch (S
When W1) is in the C position, the motor (M) is strongly driven and the battery (B) is floatingly charged as described above. However, when the battery voltage is high, this battery (B) is discharged conversely and the voltage drops. Therefore, the changeover switch (SW
When 1) is switched to the A position and the motor (M) is stopped,
The motor (M) may not restart even if the changeover switch (SW1) is returned to the B or C position. However, in the embodiment shown in FIG. 2, when the changeover switch (SW1) is in the C position, the electric charge accumulated in the capacitor (C5) is discharged when the switch is switched to the A position, and the light emitting element (OPC1) causes the capacitor (C1) to discharge. C5) and a resistor (R10) are turned on for a fixed time according to a time constant, and a large current is supplied to the battery (B) so that the battery (B) can be rapidly charged in a short time. As a result, it is possible to prepare for restarting after the battery voltage has returned.

When the changeover switch (SE1) is in the A position but the capacitor C5 is not charged, the switch (SW2) is closed to forcibly perform the rapid charge. When the switch (SW2) is closed, the timer circuit (TM) operates, and at the same time, the output terminal (d) of the timer circuit (TM) becomes "High" output and the transistor (Q3) becomes conductive. Therefore, transistor (Q3) → switch (SW1) terminal → terminal → resistor (R8) → motor (M) → battery (B) → secondary coil (SN)
A current flows and only the light emitting element (OPC2) is turned on, and the battery (B) is rapidly charged for a set time as in the example of FIG.

When the voltage of the battery (B) is high, the light emitting element (OPC2) may not be turned on because the current does not flow, but at that time, no problem occurs because rapid charging is not necessary.

(G) Effect of the Invention With the above-described configuration of the present invention, the primary and secondary of the pulse transformer, which are optimal for rapid charging, trickle charging, and load driving, are realized by the conduction / non-conduction of a plurality of photocouplers. A side input can be obtained, and a large secondary output at the time of load activation and a secondary output optimal for battery charging can be automatically adjusted and supplied.

If a capacitor for lighting the light emitting element when the switching switch is turned off is connected in parallel to the light emitting element of the photocoupler, the light emitting element is turned on for a predetermined time even when the light emitting element is off, and a pulse transformer oscillation output is generated. Since a large battery can be charged rapidly, there is an effect that various problems caused by a voltage drop of the battery such as erroneous oscillation of a pulse transformer during use of alternating current can be solved.

[Brief description of drawings]

FIG. 1 is a circuit diagram of an embodiment of the charging device of the present invention, and FIG. 2 is a circuit diagram of another embodiment. (Q1) …… Switching transistor, (PN) …… 1
Secondary coil, (TR) …… Pulse transformer, (Q2) …… Control transistor, (IPC1) (IPC2) …… Light receiving element, (SN) …… Secondary coil, (D2) …… First rectifier,
(B) …… Rechargeable battery, (SW1) …… Switching switch,
(M) …… Load, (D3) …… Second rectifier, (OPC1) (OP
C2) …… Light emitting element, (Q3) …… Adjusting transistor,
(R8) …… Current limiting resistance, (TM) …… Timer circuit, (C5)
...... Capacitor.

Claims (2)

[Claims] 1. A pulse transformer for connecting a switching transistor to a primary coil, a light receiving element of a photocoupler for changing the degree of conduction of the switching transistor, and a secondary coil of the pulse transformer connected via a rectifier. A rechargeable battery, a load connected to the battery via a changeover switch, a light emitting element of a photocoupler also connected to the secondary coil of the pulse transformer via a rectifier, the light emitting element and the changeover switch. A charging device comprising an adjusting transistor interposed between the battery and a timer circuit for controlling the transistor. 2. A light emitting element of the photocoupler is connected in parallel with a capacitor that keeps the light emitting element lit for a certain period of time even when a changeover switch is turned off.
Charging device.