JPH0232858B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention comprises a generator having a generator positive terminal and a generator negative terminal, a generator excitation winding terminal, and a battery positive terminal connecting the generator to a battery; The output voltage of the machine is controllable using a voltage regulator connected through the generator positive terminal, the generator excitation winding terminal and the generator negative terminal, and connected to the generator positive terminal. The present invention relates to a circuit device for indicating overvoltage in a device equipped with a charging monitoring lamp. The invention further comprises a generator having a generator positive terminal, a generator negative terminal, a generator excitation winding terminal, and a battery positive terminal connecting the generator to a battery, wherein the output voltage of the generator is controllable with a voltage regulator connected via a generator positive terminal, a generator excitation winding terminal and a generator negative terminal, and connected on the one hand to said generator positive terminal and on the other hand; The present invention relates to a circuit arrangement for indicating overvoltage in a device comprising a charge monitoring lamp connected to a connection point between a load and a battery.

Diode circuit arrangements with diodes and fuses have been described for some time, for example from German Patent Application No. 1913241, and also in conjunction with further fuse elements, from German Patent Application No. 1913241,
It is publicly known from Publication No. 2454020.

Diode circuit arrangements containing Zener diodes have also already been published, for example in the publication no.
1763120 and German Patent Publication No. 1815617. This device has the role of protecting a system equipped with a generator, for example an on-board power supply for a vehicle, from overvoltage. Long-term overvoltages are particularly harmful to glow lamps, as they significantly shorten their service life. Additionally, vehicle batteries can be dangerous if charged at elevated voltages for extended periods of time. The reason for this is that boiling causes the electrolyte in the battery to spill and disappear, damaging the lead plate. In addition, the corrosive action of acid due to spillage of battery fluid can cause damage to the vehicle. Also, known protection devices cannot indicate and therefore do not know if the protection device is incorrectly connected.

Furthermore, from JP-A-50-90936 a battery charging device is known which has a voltage sensing circuit which lights up a warning lamp in the event of an overvoltage. Here the lamp can only be tested when the ignition switch is closed. to indicate overvoltage,
No monitoring of other devices is carried out, and as a result there is no protection against overvoltages in the event of defects (e.g. Zener diodes) or incorrect connections in the sensing circuit (e.g. Zener diodes).
Furthermore, no indication is given that a defect exists.

Furthermore, from Japanese Patent Application Laid-Open No. 50-106438, an overvoltage protection device for a battery charging device equipped with an alternating current generator is known, which indicates not only overvoltage but also undervoltage caused by malfunction of the generator. .
In this case, the functioning of the two lamps is mutually monitored and no malfunction monitoring of other circuit arrangements, which are to detect overvoltages or undervoltages, takes place. Incorrect installation of an overvoltage protection device is not indicated, ie a non-functional overvoltage protection device is not detected in this case.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide optimal overvoltage protection for the on-board power supply of a vehicle by means of a protection circuit, and to indicate faults that have occurred, in particular overvoltages that have occurred. Furthermore, it is intended to indicate faulty connections due to incorrect installation of the protection circuit as well as failures or defects within the protection switch.

This problem is solved by the present invention in the following manner in a device of the type mentioned at the beginning in the first aspect of the invention. That is, a diode circuit arrangement comprising at least a series connection of a fuse, a Zener diode and a misconnection protection diode is inserted between the battery positive terminal of the generator and the generator negative terminal, with the A parallel shunt is connected from the connection point of said Zener diode and fuse to an additional indicating device via a connection terminal to said indicating device, said indicating device being connected to said battery positive terminal or to ground; It is used to indicate a faulty voltage that occurs due to a misconnection of a diode circuit arrangement or a short circuit in the Zener diode or in the event of an overvoltage in the Zener diode.

According to the second invention, at least a fuse,
A diode circuit arrangement including a series connection of a misconnection protection diode and a Zener diode is interposed between the generator battery positive terminal and the generator negative terminal, and the series connection fuse and misconnection protection diode are interposed between the generator battery positive terminal and the generator negative terminal. A parallel branch with a diode is led out from the connection point of , which parallel branch is connected via the connection terminal to the indicating device and the generator positive terminal to a charging monitoring lamp, so that the charging monitoring lamp is connected to the diode. Indicates faulty voltages caused by faulty connections in circuit devices or short circuits or overvoltages in Zener diodes.

According to the invention, a diode circuit arrangement, the key components of which are misconnection protection diodes and Zener diodes, is provided as an additional unit to the generator and regulator.

This diode circuit arrangement is inserted between the battery positive terminal B+ and the generator negative terminal D- and has three indicating capacities depending on the embodiment.

The circuit arrangement according to the invention does not have the disadvantages found in the above-mentioned known arrangements and has the advantage that defects in the Zener diode of the diode circuit arrangement or when installed with the wrong polarity of the diode circuit arrangement are also detected. have

Therefore, the present invention has a significant effect in that the overvoltage indicating device is significantly improved compared to the above-mentioned known devices.

The invention has the advantage that only a few commercially available components are used and that the diode circuit arrangement can be easily integrated into or attached to the generator or installed at remote locations. is obtained. The various embodiments of the diode circuit arrangement of the invention also differ in their degree of safety. In the first invention, it is possible to indicate erroneous voltages that occur in the event of a erroneous connection in a diode circuit arrangement, a short circuit in a Zener diode, and an overvoltage in a Zener diode. A further advantage of the second invention is that existing charge monitoring lamps can be used for indication.

Next, the present invention will be explained in detail using the drawings.

FIG. 1 shows a commonly used vehicle power supply system. First, the symbols of the generator connection terminals used will be explained. B+ is the battery positive terminal, D
+ is a generator positive terminal, D- is a generator negative terminal, and DF is a generator excitation winding terminal. It is indicated by the symbol below. The generator 11 has a phase winding 12 and an excitation winding 13. Main current rectifier 1 in phase winding 12
4 and an exciting current rectifier 15 are connected downstream. In addition to the ground terminal, the generator also has terminal B.
+, terminal D+, terminal DF, and terminal D-. A battery 17 is connected to the generator.

One line from the positive terminal of the battery reaches a charge monitoring lamp 19 via a main switch 18, and the other line reaches a load 22 via a switch 21. In addition to the charge monitoring lamp 19, a connection terminal belonging to the voltage regulator 23 is connected to the terminal D+. Further terminals of voltage regulator 23, namely DF and D-, are connected to corresponding terminals of generator 11. FIG. 1 additionally shows a diode circuit arrangement 24 with a series of connection terminals.
The configuration of the diode circuit device 24 and its connection terminals will now be described in detail.

FIG. 2 shows a first embodiment of the first invention of a diode circuit device 24. In FIG. The diode circuit arrangement includes a series connection of a fuse 25, a Zener diode 26 and a misconnection protection diode 27.
The cathode of the misconnection protection diode 27 is connected to the terminal D.
– is connected to. This terminal is to be connected to a corresponding connection terminal on the generator. In this case, when the diode circuit arrangement 24 is installed in the generator, it is usually fixed to the B+ terminal and the D- terminal by a connector or plug connection. Anode of misconnection protection diode 27 and Zener diode 2
6 anodes are connected together. A fuse 25 is provided between the cathode of the Zener diode 26 and a terminal B+, which is connected to the generator by a corresponding connection terminal. Terminal B+ and terminal D-
An anti-jamming capacitor 28 can be provided between the two. The circuit devices mentioned so far can sufficiently fulfill the safety function. In order to provide the desired indication, further elements are provided: a first diode 29, a second diode 31 and a resistor 32. These elements form a control device. The anode of the first diode 29 is
It is connected to the connection point between the Zener diode 26 and the fuse 25, and the cathodes of the first diode 29 and the second diode 31 are connected to each other. A resistor 32 is provided between the anode of the diode 26 and the anode of the second diode 31, which is connected to the connection terminal I to the indicating device. A light emitting diode 33 can be provided between the connection terminal I and the positive terminal B+ of the battery. Instead of a light emitting diode, a glow lamp or an indicator element can also be provided.

In a second embodiment of the first invention shown in FIG. 3, the order of the switching elements is somewhat different. The Zener diode 26 is also centrally provided in this circuit, the anode of the misconnection protection diode 24 is connected to terminal B+, and the free end of the fuse is connected to terminal D-. The polarities of the first diode 29 and the second diode 31 are reversed with respect to the first embodiment. Others are second
The configuration is the same as the first embodiment shown in the figure. The indicating element, for example the light emitting diode 33, is connected to the connection terminal I.
and ground.

FIG. 4 shows an embodiment of the second invention. In this case, a series connection of a fuse 25, a misconnection protection diode 27 and a Zener diode 26 is used. The anode of the Zener diode 26 is connected to the connection terminal D-, the cathode is connected to the cathode of the misconnection protection diode 27, and the fuse 25 is connected to the misconnection protection diode 2.
The cathode of another diode 34 is connected to the anode of the misconnection protection diode 27, and the anode of the diode 34 is connected to the connection terminal I of the diode circuit device 24. There is. In this embodiment, connection terminal I is connected to connection terminal D+.

The operation of the embodiment shown in FIGS. 2 to 4 will be explained below in detail by dividing it into functions.

1. Short circuit of the Zener diode 26 When the Zener diode 26 is short-circuited, according to the circuit of FIG. 2, a large current flows from the battery positive terminal B+ via the shunts 25, 26, 27 toward the generator negative terminal D-. As a result, the fuse 25 is blown and the indicating element 33 emits light. That is, if fuse 25 blows,
Current from battery positive terminal B+ is shunt 3
3, 31, 32, and 27 to the terminal D-.

In the circuit device shown in FIG. 3, the short circuit of the Zener diode 26 causes the fuse 25 to similarly melt, and based on this, current flows from the terminal B+ to the shunt 2.
7, 32, 31, and 33 to ground, and the indicating element 33 emits light.

According to FIG. 4, due to the breakdown or short circuit of the Zener diode 26, a high current flows from the terminal B+ to the terminal D-, which causes the fuse 25 to blow, and then the current flows from the terminal B+ through the charge monitoring lamp 19 to the diode 34, 27 and the breakdown diode 26 to terminal D-;
Therefore, the charge monitoring lamp emits light.

2 Incorrect connection of the diode circuit arrangement If the diode circuit arrangement is incorrectly connected, i.e. when the terminals B+ and D- are connected in reverse, the misconnection protection diode 27 is connected to the Zener diode 26 in all three embodiments. Prevent destruction. At the same time, an instruction for incorrect connection is given.

In the embodiment of FIG. 2, the indicating device 33 emits light. This means that the current from terminal B+ is 33,
31, 32, 26, 25, a current would then flow to the incorrectly connected terminal D- instead of the terminal B+. According to FIG. 3, in case of incorrect connection, that is, when terminals D- and B+ are connected in reverse, 25, 26, 32, 3
Since current flows to the ground via 1 and 33, an instruction is given via the instruction element 33.

In the embodiment of FIG. 4 as well, an indication of incorrect connection of the diode circuit device is given via the charging monitoring lamp. If terminals B+ and D- are connected incorrectly, current will flow from terminal B+ through the charge monitoring lamp, through diode 34 and fuse 25, to terminal D-.

In all embodiments, therefore, a misconnection of terminals B+ and D- is indicated.

3 Overvoltage at the Zener diode 26 To protect the onboard power supply from overvoltages, in particular voltage peaks, in all embodiments at least one further diode is connected to the terminals B+ and D- via a misconnection protection diode 27. A Zener diode 26 is used. When the voltage between terminals B+ and D- exceeds the Zener voltage of the Zener diode 26, the Zener diode becomes conductive and an overvoltage is therefore detected. In the embodiment of FIG. 2, this instruction is issued when an overvoltage flows and the fuse 25 blows. In this case, the current from the terminal B+ passes through the indicating element 33, the diode 31, the resistor 32, and the diode 27, and then flows to the indicating terminal D.
-, and the indicating element 33 indicates this fault.

According to FIG. 3, this instruction is also given when the fuse 25 is blown. In this case, the current from the terminal B+ flows to ground via the diode 27, the resistor 32, the diode 31, and the indicating element 33. The embodiment of FIG. 4 can also indicate this fault.

Effects of the Invention As described above, according to the present invention, it is possible to reliably indicate overvoltage of a vehicle's on-board power supply, misconnection of a diode circuit incorporated to indicate overvoltage, and short circuit of a Zener diode in the diode circuit. effective.

[Brief explanation of drawings]

FIG. 1 is a schematic circuit diagram of a vehicle on-board power supply system in which the diode circuit device of the present invention is incorporated, and FIG. 2 and FIG. FIG. 4 is a circuit diagram of the second embodiment of the invention. 11... Generator, 12... Phase winding, 13... Excitation winding, 14... Main current rectifier, 15... Exciting current rectifier, 17... Battery, 19... Charge monitoring lamp, 22... Load , 23...voltage regulator,
24... Diode circuit device, 25... Fuse, 26... Zener diode, 27... Misconnection protection diode, 28... Interference prevention capacitor, 29, 31, 32, 34... Control device, 33
...Light emitting diode.

Claims (1)

[Claims] 1. A generator having a generator positive terminal D+, a generator negative terminal D-, a generator excitation winding terminal DF, and a battery positive terminal B+ for connecting the generator to a battery, in which case The output voltage of the generator can be controlled using a voltage regulator connected via the generator positive terminal D+, the generator excitation winding terminal DF and the generator negative terminal D-, and In the circuit arrangement for indicating overvoltage in a device comprising a charge monitoring lamp 19 connected to terminal D+, a diode circuit arrangement 24 comprising at least a series connection of a fuse 25, a Zener diode 26 and a misconnection protection diode 27 is provided. is inserted between the generator battery positive terminal B+ and the generator negative terminal D-, with the parallel shunt of the diode circuit arrangement 24 being connected from the connection point of the Zener diode and the fuse to the indicating device. It is connected via the connection terminal I to an additional indicating device, which is connected to the battery positive terminal B+ or to earth and which is connected to the battery positive terminal B+ or to earth and which is connected to the battery positive terminal B+ or to the earth due to a misconnection of the diode circuit arrangement or a short circuit in the Zener diode 26. or the Zener diode 2
6. A circuit device for indicating an overvoltage, characterized in that it is used for indicating an erroneous voltage that occurs during an overvoltage in the circuit shown in FIG. 2. A generator is provided with a generator positive terminal D+, a generator negative terminal D-, a generator excitation winding terminal DF, and a battery positive terminal B+ for connecting the generator to a battery, in which case the output voltage of the generator is controllable using a voltage regulator connected via the generator positive terminal D+, the generator excitation winding terminal DF and the generator negative terminal D-;
In a circuit arrangement for indicating an overvoltage in a device with a charge monitoring lamp 19 connected to the load 22 and the connection point between the load 22 and the battery 17 on the other hand, at least a fuse 25, a misconnection protection A diode circuit arrangement 24 comprising a series connection of a diode 27 and a Zener diode 26 is interposed between the generator battery positive terminal B+ and the generator negative terminal D-, and is connected to the fuse of said series connection. A parallel branch with a diode 34 is led out from the connection point with the protection diode, which parallel branch connects the connection terminal I to the indicating device and the generator positive terminal D.
+ to a charging monitoring lamp, whereby the charging monitoring lamp indicates an overvoltage, characterized in that it indicates an incorrect voltage caused by a misconnection of the diode circuit arrangement or a short circuit or an overvoltage in the Zener diode; circuit device.