JPS5849092B2 - Storage battery charging device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for rectifying the output voltage of an alternator to charge a storage battery, and in particular to a device for charging a storage battery by rectifying the output voltage of an alternator.
The present invention relates to a charging device with an improved voltage regulator that regulates the output voltage of a phase alternator to a predetermined value.

FIG. 1 shows a conventional device for charging a storage battery as described above that is installed in a vehicle such as an automobile.
It mainly includes a DC voltage generator 10, an electromagnetic relay 20, and a voltage regulator 30.

The DC voltage generator 10 includes an alternating current generator driven by an internal combustion engine (not shown), including a three-phase star generator coil 11 and a field winding 12, and a total generator that rectifies the voltage generated by the generator. It has a wave rectifier 13 and functions to generate a charging voltage to be applied to a storage battery during operation of a vehicle or the like.

The electromagnetic relay 20 includes a t-magnetic coil 21 and contacts 22 and 23 actuated by this electromagnetic coil, and is configured to prevent the electromagnetic relay from operating when an internal combustion engine, that is, an alternator, is stopped, for example, by the operation of accessories such as a car radio. It functions to prevent a large excitation current from flowing through the field winding 12 and discharge the storage battery 1, and to turn on the charging indicator light 2.

As will be described later, the voltage regulator 30 is connected to the DC voltage generator 10.
It functions to maintain the output voltage from the battery at a constant value and charge the storage battery 1 at a specified voltage.

In the apparatus shown in FIG.
When the is turned on, the scooter of the internal combustion engine (not shown)
At the same time, the voltage of storage battery 1 is applied to diode 2
A current flows through the electromagnetic coil 21 through the electromagnetic coil 21, and the contacts 22 and 23 are closed.

Therefore, an exciting current flows from the storage battery 1 through the contacts 22 and 23, the voltage regulator 30, and the field winding 12, so that
The phase star generator coil 11 is energized and starts generating electricity, and a voltage is also generated at the neutral point 14.

After starting, the starter switch 3 is immediately turned off and no current flows from the storage battery 1 to the electromagnetic coil 21, but due to the voltage generated at the neutral point 14, current flows to the electromagnetic coil 21 via the diode 25. Contacts 22 and 23 remain closed.

Therefore, while the AC generator is operating, the contacts 22 and 23 of the electromagnetic relay 20 are closed due to the neutral point voltage, and the voltage of the storage battery 1 is applied to the field winding 12, so that the DC voltage generator 10 continues to provide the output voltage normally.

A conventional voltage regulator 30 in a device operating in this manner includes two transistors 31 and 32, resistors 33 and 34 forming a voltage divider circuit, a Zener diode 35 for voltage detection, and capacitors 36 and 37. , resistors 38 and 39,
It is composed of a diode 40.

Note that the resistor 38 is provided to ensure smooth operation of the transistor 32, and the capacitors 36 and 37 are provided to ensure prompt and reliable operation of the transistors 31 and 32.

In the conventional configuration as described above, when the starter switch 3 is turned on when starting the internal combustion engine, the electromagnetic relay 20 is activated as described above, and current flows through the base circuit of the transistor 31, so that the transistor 21 is electrically connected between the emitter and the collector, and an exciting current flows through the field winding 12.

Therefore, a DC voltage is generated between the output terminals (a-b) of the DC voltage generator 10.

In this case, the Zener diode is configured to be conductive when the generated DC voltage exceeds a predetermined voltage, and to be non-conductive when the generated DC voltage is below a predetermined voltage.

Therefore, when the rotational speed of the alternator increases and the voltage between the output terminals increases, the voltage at the connection point J of the voltage divider circuit also increases, and the Zener diode 35 becomes conductive.

As a result, the transistor 32 becomes conductive, so the transistor 31 becomes non-conductive, the excitation current to the field winding 12 is cut off, and the DC voltage between the output terminals (a-b) decreases.

On the other hand, when the voltage between the output terminals becomes less than a predetermined value, the voltage at the connection point J of the voltage dividing circuit also decreases, and the Zener diode 35 becomes non-conductive.

Therefore, the transistor 32 becomes non-conductive, so the transistor 31 becomes conductive, and an excitation current is applied to the field winding 12, so that the DC voltage between the output terminals increases.

By repeating the above operations, the output voltage of the DC voltage generator 10 is controlled to a predetermined value, and thereby the storage battery 1
to charge.

However, in a device using a conventional voltage regulator as shown in FIG. When turned ON and OFF by
5 malfunctions and the alternator stops generating electricity.

The causes of such an inconvenient power generation stoppage phenomenon are considered as follows.

When the switch 5 of the electrical load 4 is turned on during operation, the voltage between the load side terminals (e-f) changes to the voltage between the output terminals (a-b) due to the voltage drop corresponding to the load current flowing through the load line 6. and the terminal voltage of the storage battery 1, and therefore,
The Zener diode 35 detects such a low terminal voltage on the load side via a voltage dividing circuit made up of resistors 33 and 34, and the storage battery 1 is charged with a high terminal voltage.

Next, when the switch 5 is turned off during operation, no load current flows through the load line 6, so there is no voltage drop, and therefore the load side terminals (e-f) are connected to the output terminals (a-b). The terminal voltage of the storage battery 1 is applied, and this applied voltage is the high voltage when the switch 5 is turned ON/L.

Therefore, the storage battery 1 continues to self-discharge until its terminal voltage drops to the regulated voltage of the voltage regulator 30.

While the electrical load changes in this way, the Zener diode 35 of the voltage regulator 30 detects a voltage higher than the regulated voltage, so the Zener diode becomes conductive and the transistor 31 becomes non-conductive as described above. A power generation stop state occurs.

Incidentally, such a state is likely to occur when the storage battery 1 is in a fully charged state.

When the power generation is stopped as described above, the contacts 22 and 23 of the electromagnetic relay 20 are opened due to a drop in the neutral point voltage of the alternator, making it impossible for the alternator to generate power again, and causing the internal combustion engine to stop. In order to make regeneration possible, it is necessary to provide a suitable manual switch 7 between the contacts 22 and 23, and to turn on the switch when power generation is stopped.

It is clear that the occurrence of a power generation halt state as described above causes an extremely large problem in the operation of vehicles and the like.

The present invention provides an internal combustion engine that maintains the contacts of the electromagnetic relay in a closed state despite changes in the electrical load during operation of the internal combustion engine, that is, despite voltage drops occurring on the load line. It is an object of the present invention to provide a charging device with an improved voltage regulator for use in a device for rectifying the output voltage of an alternator driven by an engine to charge a storage battery.

The invention will be described below with reference to illustrated embodiments.

FIG. 2 shows a device for charging a storage battery mounted on a vehicle such as an automobile according to the present invention, and its configuration and operation are the same as the device shown in FIG. 1 except for the voltage regulator 50. .

The voltage regulator 50 is similar to the voltage regulator 30 in FIG.
A first transistor 31 that performs a switching operation to provide an excitation current that energizes the field winding 12 of the alternator.
, a second transistor 32 that controls the switching operation of the first transistor 31, resistors 33 and 34 forming a voltage dividing circuit, and a Zener diode 35 for voltage detection.
,including.

Voltage regulator 50 further includes an impedance element, for example a resistor 51, inserted between the collector of second transistor 32 and field winding 12.

Therefore, when the Zener diode 35 detects a voltage higher than the regulated voltage that causes the alternator to stop generating electricity as described above, the Zener diode 35 becomes conductive.
The second transistor 32 becomes conductive and the first transistor 31 becomes non-conductive, but the second transistor 32
Since the output current, that is, the collector current, flows slightly through the resistor 51 to the field winding 12 as an excitation current, occurrence of a power generation stop state is avoided, and the contacts 22 and 23 of the electromagnetic relay 20 are maintained in a closed state. can do.

Note that up to the allowable collector current range of the transistor 32,
Since it can be used as the excitation current for the field winding 12, even if the wiring resistance increases due to the voltage drop in the load line 6 and the use of a connector during vehicle wiring, the value of the resistor 51 can be appropriately selected to maintain the desired value. can achieve the objectives of

As described in detail above, according to the present invention, it is possible to avoid the inconvenient power generation stop state of the alternator, so stable operation of vehicles etc. is guaranteed, and furthermore, the above-mentioned manual switch for regeneration can be avoided. 7 is no longer required, simplifying the charging device,
It is also expected to save labor in operation.

Furthermore, the present invention has a relatively large tolerance for increases in wiring resistance, so it can be easily applied to large vehicles with long wiring lengths, and it is not affected by other power sources, so parallel operation is possible. You can also do

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of a conventional device for rectifying the output voltage of an alternator to charge a storage battery. FIG. 2 is a circuit diagram illustrating an embodiment of an apparatus for rectifying the output voltage of an alternator and charging a storage battery according to the present invention with an improved voltage regulator. Explanation of symbols, 1...Storage battery, 2...Charging indicator light, 3...Starter switch, 4...
...Electrical load, 5...Switch, 6...
...Load line, 7...Manual switch, 10...
...DC voltage generator, 11...3-phase star generator coil, 12...field winding, 13...
・Full wave rectifier, 14... Neutral point, 20...
... Electromagnetic relay, 21 ... Electromagnetic coil, 22,
23...Contact, 24,25.40...
Diode, 30, 50...Voltage regulator, 3L
32...Transistor, 33,34.38,3
9.51...Resistor, 35...Zener diode, 36,37...Capacitor.

Claims (1)

[Scope of Claims] 1. An alternating current generator, a rectifier 2 that rectifies the output voltage generated by the alternator, a storage battery that is charged by the rectified output voltage, and a storage battery that is energized during power generation of the alternator. and an electromagnetic relay having a contact that is turned into a closed state or an open state by an electromagnetic coil that is deenergized when power generation is stopped, and a charging display device that indicates the charging state of the storage battery according to the open/closed state of the contact of the electromagnetic relay. The rectified output voltage is detected through the contacts of the electromagnetic relay, and in response to the detected output voltage, the excitation current to the field winding of the alternator is controlled to adjust the output voltage. A voltage regulator that adjusts to a predetermined value; In the storage battery charging device, the voltage regulator includes a contact point of the electromagnetic relay and a partial voltage of the voltage regulator to detect the rectified output voltage. a Zener diode connected to the rectifier via a resistor; an emitter terminal connected to the rectifier via a contact of the electromagnetic relay for controlling the supply of excitation current to the field winding; a first transistor having a collector terminal connected to a field winding and a base terminal; an emitter connected to an emitter terminal of the first transistor for controlling the conduction state of the first transistor; a second transistor having a collector terminal connected to the base terminal of the first transistor, and a base terminal connected to the Zener diode; and a collector terminal of the second transistor and the field. an impedance element inserted between the alternating current generator and the magnetic winding, and a voltage that exceeds a predetermined value of the output voltage due to fluctuations in the electrical load connected to the storage battery during power generation of the alternator. When the Zener diode is detected, its conduction causes the second transistor to conduct and the first transistor to become non-conductive, causing the first transistor to supply an excitation current to the field winding. At the same time that the alternator is stopped, the collector current of the second conductive transistor is supplied to the field winding via the impedance element, thereby avoiding the alternator from stopping generating electricity. A storage battery charging device characterized by comprising: