JPS631569Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of a charging display circuit device for a charging generator that is driven by an engine of an automobile and charges a battery.

FIG. 1 is an electrical circuit diagram showing this type of device commonly used in the past. In this diagram, G is a charging generator driven by an engine (not shown);
This charging generator G includes a generator coil 1 wound around a stator, a field coil 2 wound around a rotor, a main rectifier 3, an auxiliary rectifier 4, brushes 5 and 5',
It is connected to slip rings 6 and 6'. VR
is a well-known transistor-type voltage regulator, and this voltage regulator VR includes Darlington-connected switching transistors 7 and 8, a voltage detection transistor 9, a diode 10, and a Zener diode 1.
1, capacitors 12 and 13, and resistors 14 to 1
It is more like 9. Next, L is an indicator light, S is a manual switch, and B is a battery, which are connected as shown in the figure.

The conventional device shown in FIG. 1 configured as described above is
First, when the manual switch S is closed before starting the engine (not shown), the voltage of the battery B passes through the manual switch S, the indicator light L, and the resistor 15 of the voltage regulator VR to the Darlington-connected switching transistor 7. , 8, so that these transistors 7, 8 are turned on,
Manual switch S and indicator light L are connected to the battery B.
and brushes 5, 5', slip rings 6, 6',
An excitation current is supplied to the circuit consisting of the field coil 2 and the transistors 7 and 8, which lights up the indicator light L, and the output voltage of the charging generator G has not yet been established and the battery B is in an uncharged state. .

Next, when the engine is started and the charging generator G is driven by the engine, the field coil 2 is supplied with excitation current from the battery B as described above, so the voltage generated in the generator coil 1 is It increases almost in proportion to the increase in speed, and when the rotation speed reaches a predetermined value, the generated voltage becomes higher than the voltage of battery B, and a charging current is supplied to battery B via the main rectifier 3. Along with this, until now the battery B has been connected via manual switch S and indicator light L.
The excitation current, which had been flowing more, now flows from the generator coil 1 through the auxiliary rectifier 4, and switches to a so-called self-excitation current, so the indicator light L
goes out, indicating that battery B is being charged by charging generator G.

Note that the operation of the voltage regulator VR, which controls the self-excitation current intermittently so that the voltage generated by the power generating coil 1 does not rise to a high voltage higher than a predetermined value, is well known, so a description thereof will be omitted.

However, in the conventional device described above, when the manual switch S is closed and the indicator light is on, the output voltage of the charging generator G is lower than the terminal voltage of the battery B, and the battery B is in a non-charging state. When the indicator light L goes out, the output voltage of the charging generator G is established and the driver is informed that the battery B is in a charging state, but there are the following disadvantages: It turned out that there is.

That is, while the charging generator G is being driven by the engine, the field of the field coil 2 may cause, for example, abnormal wear of the contact portion between the brushes 5, 5' and the slip rings 6, 6', disconnection of the field coil 2, If an accident occurs in which the switching transistors 7 and 8 are cut off due to damage, etc., the field coil 2 will be de-energized, the voltage generated by the generator coil 1 will rapidly drop, and the battery B will be in an uncharged state. Despite the transition, the circuit of field coil 2 is cut off, so no current flows from battery B to manual switch S and indicator light L, so indicator light L remains off. Therefore, the charging generator G operates normally and the battery B is supposed to erroneously notify the driver that it is in a charging state. As a result, the driver operates for a long time without noticing the failure of the charging generator G, which causes the battery B to become over-discharged and become unusable, which is a serious drawback.

The present invention has been particularly devised for the purpose of solving the above-mentioned drawbacks through simple improvements, and an embodiment of the present invention shown in FIG. 2 will be described below.

In this Fig. 2, parts indicated by the same reference numerals as in Fig. 1 indicate the same or equivalent parts as those in Fig.
To explain the differences from the diagram, a resistor R2 is connected in parallel with the indicator light L, and a resistor R1 whose one end is connected to the connection point T on the field coil 2 side of the indicator light L.
A normally closed contact P of an electromagnetic relay SR is connected in series between the other end and the ground, one end of the excitation coil of the electromagnetic relay SR is grounded, and the other end is the neutral point N of the generating coil 1 of the charging generator G. It is connected to the.

In the embodiment of the present invention configured as described above, when the manual switch S is closed before starting the engine as in the conventional case, the voltage of the battery B is applied to the manual switch S, the resistor R2, and the brushes 5, 5. An excitation current is supplied to the field circuit consisting of the coil 2, the slip rings 6, 6', the field coil 2, and the transistors 7, 8, and the potential difference across the resistor R2 causes the indicator light L to
lights up, indicating that the output voltage of charging generator G has not yet been established and battery B is in an uncharged state.

Then, when the engine is started and the charging generator G is driven by the engine, the voltage generated in the generator coil 1 increases rapidly due to the excitation of the field coil 2 almost in proportion to the increase in rotational speed. , the generated voltage becomes higher than the voltage of battery B, and a charging current is supplied to battery B via the main rectifier 3. At the same time, the excitation current that previously flowed from battery B to field coil 2 is supplemented by generator coil 1. The current flows through the rectifier 4, causing the indicator light L to go out, indicating that the charging generator G is in the charging state. On the other hand, at this time, the voltage at the neutral point N of the generator coil 1 is the relay coil W of the electromagnetic relay SR.
is applied to, thereby opening contact P and resistor R
1 to prevent unnecessary current from flowing through the contact P.

Next, while the charging generator G is being driven by the engine, the circuit of the field coil 2 may be damaged, for example, due to abnormal wear of the contact portion between the brushes 5, 5' and the slip rings 6, 6', or disconnection of the field coil 2. If an accident occurs in which the switching transistors 7 and 8 are cut off due to damage, etc., the field coil 2 becomes de-energized, so the voltage generated by the generator coil 1 rapidly decreases and the battery B becomes uncharged. At the same time, the voltage at the neutral point N of the generator coil 1 also decreases, and the excitation current of the relay coil W that has been flowing until now no longer flows, thereby causing the contact P to close. Therefore, at this time, from the battery B to the manual switch S,
Current flows through the circuit between resistors R2 and R1 and contact P,
Due to the potential difference between both ends of the resistor R2, the indicator light L is
The circuit of the field coil 2 lights up dimmer than when it is normal, and this causes the driver of the car to receive a warning from the charging generator G.
It is possible to notify that there is a disconnection accident in the circuit of the field coil 2.

As is clear from the above description, the present invention includes a resistance between the field coil side contact of the indicator light and the ground in the field coil circuit of the charging generator, and an electromagnetic field that opens at the neutral point voltage of the charging generator. By connecting the normally closed contact of the relay in series, an extremely simple improvement, even if the field coil circuit is disconnected and the excitation current is cut off, the indicator light is turned on and the charging generator is activated. Since it is possible to display that the battery is abnormal and the battery is in a non-charging state, the driver can immediately know that there is an abnormality in the charging generator. Therefore, it is possible to completely eliminate the serious drawback of battery over-discharging and unusability without knowing this, as in the past, and this has a significant practical effect.

[Brief explanation of the drawing]

FIG. 1 is an electrical circuit diagram of a conventional device of this type, and FIG. 2 is an electrical circuit diagram of an embodiment of the device of the present invention. In the diagram, G is the charging generator, VR is the voltage regulator, and L
is an indicator light, S is a manual switch, B is a battery, R
1 and R2 are resistors, SR is an electromagnetic relay, 1 is a generating coil, 2 is a field coil, 3 is a main rectifier, 4 is an auxiliary rectifier, 5 and 5' are brushes, and 6 and 6' are slip rings.

Claims (1)

[Scope of utility model registration request] At the initial stage of startup of the charging generator, an exciting current is supplied from the battery to the field coil of the charging generator driven by the engine through a manual switch and an indicator light to light up the indicator light, and the charging generator In a charging display circuit device for a charging generator configured to supply a self-exciting current to the first field coil after the output voltage is established, the exciting current from the battery is cut off and the indicator light is turned off. A charging generator characterized in that a resistor is connected in series between a field coil side connection point of the indicator light and ground, and a normally closed contact of an electromagnetic relay that opens at a neutral point voltage of the charging generator. Charging display circuit device.