JPH0317573Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a device for charging a battery mounted on a vehicle or the like driven by an internal combustion engine.

[Summary of the invention] The present invention is a battery charging device that charges a battery from a magnet generator through a regulator, and includes a battery short-circuit prevention diode in the forward direction with respect to the charging current between the voltage adjustment circuit of the regulator and the battery. This prevents the battery from being short-circuited through the inside of the regulator when the output terminal of the generator is accidentally grounded or due to insulation deterioration.

[Prior Art] Vehicles such as two-wheeled vehicles driven by internal combustion engines are equipped with a battery in addition to a magnet generator driven by the engine, and the battery powers a starter motor for starting the engine, a turn signal, a horn, etc. It drives magnetism. Vehicles equipped with a battery as described above are provided with a battery charging device that charges the battery from a magnet generator attached to the engine through a regulator in order to charge the battery.

The regulator that makes up this type of charging device is
Generally, a magnet generator is equipped with a rectifier circuit that supplies charging current to the battery, and a voltage adjustment circuit that shorts the output terminals of the magnet generator when the terminal voltage of the battery exceeds a set value. The rectified output of the magnet generator is supplied to the battery only when the terminal voltage is less than a set value.

Figure 2 shows the configuration of a conventional battery charging device. In the figure, 1 is a magnet generator driven by an engine, 2 is a battery mounted on a vehicle, etc., and 3 is a terminal of battery 2. This is a regulator that supplies charging current from the generator 1 to the battery according to the voltage. The regulator 3 consists of bridge-connected diodes D1 to D4, and the AC input terminals are the output terminals 1a and 1 of the generator 1.
The anodes are commonly connected to the diode bridge full-wave rectifier circuit 31 connected to b and the positive DC output terminal of the rectifier circuit 31 connected to the positive terminal of the battery 2, and the cathodes are connected to different AC input terminals of the rectifier circuit 31. Thyristor for connected voltage regulation
Th1 and Th2, and a control circuit 32 that detects the terminal voltage of the battery 2 and supplies an ignition signal to the thyristors Th1 and Th2 when the terminal voltage of the battery 2 exceeds a set value, and a rectifier circuit 31.
A battery 2 is connected between the output terminals 3a and 3b of the regulator 3, which are connected to the current output terminal of the regulator 3.

In this example, thyristor Th1 and diode D
1, thyristor Th2, and diode D2 constitute a generator output short-circuit circuit that short-circuits the output terminals of the magnet generator 1, and the short-circuit circuit and the control circuit 32 cause the terminal voltage of the battery to exceed a set value. A voltage adjustment circuit is configured that short-circuits the output terminals of the generator 1 when the voltage is exceeded.

In the above charging device, when the terminal voltage of the battery 2 is less than the set value, the control circuit 32 does not supply the ignition signal to the thyristors Th1 and Th2, so the thyristors Th1 and Th2 are not conductive. At this time, a rectifier circuit 3 consisting of diodes D1 to D4
1 rectifies the AC output of the generator 1 and supplies charging current to the battery 2. When the terminal voltage of battery 2 exceeds the set value, control circuit 32
In order to supply the ignition signal to Th1 and Th2, when the magnet generator 1 is generating an output voltage in the direction of the solid arrow shown in the figure, power is generated through the path of the generator's terminal 1a → diode D2 → thyristor Th2 → terminal 1b. When the output of the generator 1 is short-circuited and the magnet generator 1 is generating an output voltage in the direction of the dashed arrow shown in the figure, the terminal 1b of the generator → diode D1 → thyristor
The output of the generator 1 is short-circuited on the path from Th1 to terminal 1a. As a result, the supply of charging current to the battery 2 is stopped, and the terminal voltage of the battery 2 becomes lower than the set value. When the terminal voltage of the battery 2 becomes less than the set value, the control circuit 32 controls the thyristors Th1 and Th2.
To stop supplying the ignition signal to the thyristor
Th1 and thyristor Th2 are cut off when their respective anode-cathode voltages become zero. Thereafter, the terminal voltage of the battery 2 is maintained at approximately the set value so that the battery 2, which is subjected to repeated operations similar to those described above, is not overcharged.

[Problems to be solved by the invention] In the above battery charging device, the thyristor
If at least one output terminal of the magnet generator 1, for example, the output terminal 1b, is accidentally grounded while the ignition signal is being applied to Th1 and Th2 (the voltage adjustment operation is being performed), the battery 2 Since the short circuit current Is flows from the thyristor Th2, the output terminal 1b of the generator, and the ground, the thyristor
There was a problem with Th2 destroying it. A similar problem also occurs when the output terminal of the generator is grounded due to insulation deterioration or the like.

An object of the present invention is to provide a battery charging device using a magnet generator as a power source, which solves the above problems.

[Means for solving the problem] The present invention provides a method for connecting a plurality of output terminals 1 in an ungrounded state.
a, 1b, a diode bridge full-wave rectifier circuit 31 that rectifies the alternating current voltage obtained between the output terminals of the magnet generator and supplies charging current to the battery 2, and a full-wave rectifier circuit 31. A plurality of voltage regulating thyristors Th1 and Th2 whose anodes are commonly connected to the DC output terminals of the circuit and whose cathodes are respectively connected to different AC input terminals of the full-wave rectifier circuit.
and a control circuit 32 that supplies firing signals to a plurality of thyristors when the terminal voltage of the battery Z exceeds a set value, and the negative terminal of the battery 2 is grounded. be.

In the present invention, in order to prevent current from flowing from the battery 2 to the thyristor side when the output terminal of the generator is grounded, the positive DC output terminal of the full-wave rectifier circuit 31 and the plurality of thyristors Th1, Th
A diode D5 for preventing battery short circuit in the forward direction with respect to the charging current was inserted between the connection point with the anode of No. 2 and the positive terminal of the battery.

[Operation of the invention] As described above, the positive side DC output terminal of the full-wave rectifier circuit 31 and the plurality of voltage regulating thyristors Th1,
When a battery short-circuit prevention diode D5 is inserted in the forward direction of the charging current between the connection point with the anode of Th2 and the positive terminal of the battery, thyristors Th1 and Th2 become conductive and the output of generator 1 is short-circuited. When at least one of the output terminals of the generator 1 is grounded in a state where the thyristor is connected, current can be prevented from flowing from the battery 2 to the thyristor. Therefore, it is possible to prevent the battery from being short-circuited when the output terminal of the generator is grounded, and it is also possible to prevent the thyristor from being destroyed due to excessive current flowing through the voltage regulating thyristor. .

[Embodiments] Examples of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the present invention, and in this embodiment, the same parts as those in FIG. 2 are given the same reference numerals, and the explanation thereof will be omitted. In this embodiment, battery 2 is connected between the anodes of thyristors Th1 and Th2 and the positive terminal of battery 2.
A forward battery short-circuit prevention diode D5 is inserted for the charging current. Other points are similar to the example shown in FIG.

When configured as in the above example, the thyristor
Even if at least one of the output terminals 1a and 1b of the generator 1 is short-circuited while the ignition signal is being supplied to Th1 and Th2, the diode D5 prevents current from flowing from the battery 2 to the thyristors Th1 and Th2. This prevents the battery 2 from being short-circuited. Therefore, when the output terminal of the generator 1 is grounded, it is possible to prevent excessive current from flowing through the thyristors Th1 and Th2, and it is possible to prevent the thyristors Th1 and Th2 from being destroyed.

In the above embodiment, a single-phase generator is used as the magnet generator 1, but a multi-phase magnet generator with three or more phases and a multi-phase diode bridge that rectifies the output of the magnet generator are used. a full-wave rectifier circuit; a plurality of voltage-adjusting thyristors having anodes commonly connected to a positive DC terminal of the full-wave rectifier circuit and cathodes connected to different AC input terminals of the full-wave rectifier circuit; The present invention can be similarly applied to a battery charging device equipped with a control circuit that supplies firing signals to a plurality of thyristors when the terminal voltage of the battery exceeds a set value.

[Effects of the invention] As described above, according to the invention, by providing the battery short-circuit prevention diode, it is possible to prevent short-circuit current from flowing from the battery through the thyristor when the output terminal of the generator is grounded. Therefore, it is possible to prevent the thyristor from being destroyed due to excessive current flowing through the voltage regulating thyristor, and reliability can be improved.

[Brief explanation of the drawing]

Figure 1 is a circuit diagram showing one embodiment of the present invention, Figure 2 is a circuit diagram showing an embodiment of the present invention.
The figure is a circuit diagram showing a conventional example. 1... Magnet generator, 2... Battery, 3... Regulator, 31... Rectifier circuit, D1 to D4...
Diodes that make up the rectifier circuit, Th1 and Th2
. . . Thyristor that together with diodes D1 and D2 constitute a generator output short circuit, 32 . . . A control circuit that supplies an ignition signal to the thyristor.

Claims (1)

[Claims for Utility Model Registration] A magnet generator having a plurality of output terminals in an ungrounded state, and a diode bridge that rectifies the alternating current voltage obtained between the output terminals of the magnet generator and supplies charging current to a battery. a full-wave rectifier circuit; a plurality of voltage-adjusting thyristors having anodes commonly connected to the DC output terminals of the full-wave rectifier circuit and cathodes connected to different AC input terminals of the full-wave rectifier circuit; a control circuit that supplies an ignition signal to the plurality of thyristors when a terminal voltage of the full-wave rectifier circuit exceeds a set value, and a negative terminal of the battery is grounded. A battery short-circuit prevention diode in the forward direction with respect to the charging current is inserted between a connection point between the positive side DC output terminal and the anodes of the plurality of thyristors and the positive terminal of the battery. A battery charging device that uses a magnetic generator as a power source.