JPS58190242A - Temperature limiting type charging generator controller - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides temperature-limited charging generator control that limits the output depending on the temperature of a control device that is installed in a vehicle and charges a storage battery with the rectified output of an alternator driven by an internal combustion engine. This relates to improvements in equipment.

First, a conventional device of this type is shown in FIG. 1 and will be explained. 1st
In the figure, (1) is an alternating current generator that is installed in a vehicle (not shown) and driven by an internal combustion engine (not shown), and has an armature coil (101) and a field coil connected in a three-phase star shape. (102). (2) is a three-phase full-wave rectifier that full-wave rectifies the AC output of the generator (1), (201) is its first rectified output end, (202) is its second rectified output end, (
208) is the eighth rectified output end.

(3) controls the output voltage of the generator (1) to a predetermined value by controlling the current flowing through the field coil (102); This is a type voltage regulator that is composed of the following parts. That is, (801) is a surge absorbing diode connected to both ends of the field coil (102), (802)
(808) is an output transistor which intermittents the field current of the field coil (102) and is connected to each other in Darlington; (804) is the transistor (3θ2) (8
The resistance (805) constituting the base circuit of 08) is -
A control transistor that controls the transistors (802) and (808) intermittently; (806) is a first Zener diode that detects the output voltage of the generator (1) and becomes conductive when it reaches a predetermined value; (808) (809) are resistors connected in series to form a voltage dividing circuit for voltage detection; (811)
) is a resistor that constitutes a voltage dividing circuit for temperature detection of the voltage regulator (3), (812) is a heat-sensitive switching element whose resistance value rapidly increases in the positive direction when the set temperature is exceeded, (807)
(810) is the higher one of the connection point potentials of the voltage detection circuits (808) (809) and the temperature detection circuits (811) (812), and the Zener diode (806)
), a diode forming an OR circuit that makes the transistor (805) conductive, and (818) an initial excitation resistance.

(4) is a storage battery charged by the rectifier of the generator (1), (5) is a key switch, and (6) is a charging indicator light.

The operation of the conventional device configured as above will be explained. First, when the key switch (6) is closed when starting the internal combustion engine, base current is supplied from the storage battery (4) to the transistors (802) (808) via the key switch (5), and the transistors (802) (sos) is conductive. When the transistor (802) (ao8) becomes conductive, a signal is transmitted from the storage battery (4) to the key switch (6) and the charging indicator light (6).
) and the field coil (1) via the initial excitation resistance (818).
02) generates field magnetomotive force. At this time, since the connection point potential of the voltage detection circuit voltage dividing resistor (SOS) (809) and the temperature detection voltage dividing circuit elements (811) (812) is low, the zener diode (806) and the transistor (805)
) remains non-conducting. Therefore, the charging indicator light (6)
is lit! [Displays the non-charging status of the battery (4).

Next, when the engine starts in this state and the generator W1 (1) is driven, the armature coil (101)
induces an alternating current output. The AC output is passed through a full-wave rectifier (
2), and outputs a positive voltage to the first rectified output terminal (201) and the second rectified output terminal (202), and outputs a negative voltage to the eighth rectified output terminal. When the output voltage of the second rectified output terminal (202) exceeds a predetermined value, the resistor (!308) (80
9) The connection point potential rises and the Zener diode (GOS)
The transistor (80δ) is conductive and the transistor (80δ) is conductive.
02) (808), the field current decreases, and the output voltage induced in the armature coil (101) decreases. When the output voltage decreases to below the predetermined value, the zener diode (806) and transistor (805) become non-conductive, and the transistors (802) and (808) become conductive, causing the field current to increase again and the output voltage to rise. By repeating this operation, the output voltage of the generator (1) is controlled to a predetermined value. On the other hand, the first rectified output end (20
1) At the same time, the potential of the second rectifier output terminal (202) also increases by -F, and when the terminal voltage of the storage battery (4) becomes almost the same voltage, the voltage across the charging indicator light decreases and the charging indicator light (6 ) goes out to display the state of charge of the storage battery (4).

Next, for some reason (for example, when the internal combustion engine suddenly shifts to idle operation after high-load operation), the ambient temperature of the generator suddenly increases, and the generator (1) loses electricity. If the load (not shown) is large, if it attempts to reach a temperature exceeding the temperature that will lead to thermal damage due to self-heating or extremely shortened lifespan, the generator (1) should be installed inside or outside the generator (1). The temperature of the voltage regulator (3) also increases, and the temperature of the heat-sensitive switching element (812) exceeds the set temperature, causing the resistance value to rapidly increase in the positive direction. Then, the potential at the connection point between the resistor (811) and the heat-sensitive switching element (st2) rises, and the voltage increases through the diode (810), regardless of the potential at the connection point between the voltage-detecting voltage dividing circuit resistors (808) and (809). The Zener diode (806) and the transistor (805) are brought into conduction, and the transistors (802) and (808) are brought into a fast-acting state. Therefore, the field current is cut off and the generator (1) stops generating electricity. Therefore, the generator (1) generates self-heating (
most of the self-heating) disappears, and the temperature rise value drops rapidly. This temperature rise value is determined by the heat-sensitive switch element (81
When the temperature drops below the set temperature in step 2), the resistance value decreases rapidly again, and the potential at the connection point between the resistor (811) forming the temperature detection circuit and the heat-sensitive switching element (812) decreases, becoming irrelevant to the operation and returning to zero. A diode (806) and a transistor (805) are connected to a resistor (808) which constitutes a voltage detection circuit.
) (809) begins to operate under the influence of the connection point potential.

However, in the conventional device described above, the resistance value of the heat-sensitive switching element changes rapidly depending on the set temperature and switches, so the field current turns on and off in a certain period, and the generated voltage also turns on and off. do. Therefore, the temperature is kept constant at a high temperature by repeating interruptions near the set temperature of the heat-sensitive switching element, which has the disadvantage of lowering reliability.

The present invention provides an excellent overtemperature-limited charging generator control device that eliminates the above-mentioned drawbacks.

An embodiment of the present invention shown in FIG. 2 will be described below. In FIG. 2, (at4) is the resistance (at4) of the detection circuit.
809) and the ground, a voltage reducing transistor (815) is the second Zener diode, (81
6) (817) is a diode forming an OR circuit, (
812) is a first heat-sensitive switching element whose resistance value increases rapidly above a first predetermined temperature, which is the maximum allowable temperature for a short time (approximately 120 degrees Celsius equivalent to the generator ambient temperature), and this is the same as the conventional device. However, the connection with the resistor (811) is reversed. (818) is connected in parallel with the resistor (811), and conducts once when the transistor (814) is cut off.
The above resistor (811) is short-circuited at
4) A hysteresis transistor for the purpose of maintaining the cutoff, (819) (820) is a diode, (821'
) is the base circuit resistance of the transistor (818),
(822) has a maximum continuous allowable temperature lower than the first heat-sensitive switching element (812) (approximately 1
The second heat-sensitive switching element (828) whose resistance value increases rapidly above a second predetermined temperature (00°C) is a series voltage dividing resistor.

The operation of an embodiment of the apparatus of the present invention configured as described above will be explained. First, while the generator is operating at a temperature below the maximum continuous allowable temperature, both the first heat-sensitive switching element (812) and the second heat-sensitive switching element (822) maintain a low resistance as they are below the operating temperature. 2 Zener diodes (81
5), the transistor (814) is conductive, the resistors (808) and (809) forming the voltage detection circuit are grounded and function normally, and the output voltage of the generator (1) is connected to the storage battery (6).
) is controlled to a first predetermined voltage value that is optimal for charging.

Next, when the ambient temperature of the generator (1) rises for some reason and exceeds the second predetermined temperature, which is the maximum continuous allowable temperature, the resistance value of the second heat-sensitive switching element (822) suddenly increases. The potential at the connection point with the resistor (828) decreases, and the base current of the transistor (814), which had been flowing through the diode (817) and the Zener diode (815), disappears. Since (812) is not activated, the transistor (814) maintains conduction as base DC is supplied through the heat-sensitive switching element (812), the diode (816), and the Zener diode (815).

Furthermore, when the ambient temperature of the generator (1) rises and exceeds the first predetermined temperature, which is the maximum allowable temperature for a short time, the first heat-sensitive switching element (812) is activated and the resistance value increases rapidly. The potential at the connection point with the resistor (811) also drops, the Zener diode (815) and the transistor (814) are cut off, and the lower resistor (809) forming the voltage detection circuit is cut off. When the resistor (809) is cut off, the resistor (80
8) In the Zener diode (806) circuit, the base current continuously flows through the transistor (805), maintaining the conduction of the transistor (805) and reducing the transistor (802) (
80g) will maintain the cutoff, and the field coil (10
The field current of 2) is cut off, and the generator (1) stops outputting. When the generator (1) stops outputting, self-heating due to the output current disappears, and the temperature increase value rapidly decreases. At this time, the transistor (814) is cut off, so the transistor (81g) is connected to the resistor (821) and diode (81).
9), the base current flows through it and is conductive. Therefore, the resistor (811) is in a short-circuited state. In this state, the temperature of the generator (1) decreases to a value lower than the first predetermined temperature and higher than the second predetermined temperature, and the resistance value of the first heat-sensitive switching element (812) is lowered. Even if the voltage decreases to a normal value, the potential at the connection point with the resistor (811) is maintained by the zener diode (
815) The transistor (814) becomes conductive (1111) lower than the value obtained, and the transistor (814) remains cut off.

When the temperature further decreases and becomes lower than the second predetermined temperature, the second heat-sensitive switching element (822) also decreases to a normal resistance value, the connection potential with the resistor (82B) increases, and the diode ( 817) A base current is supplied to the transistor (814) via the Zener diode (815), and the transistor (814) becomes conductive.

When the transistor (814') becomes conductive, the resistors (808) and (809) forming the voltage detection circuit are grounded and function normally, controlling the output voltage of the generator to the first predetermined voltage value again, and 821) is caused to flow through the diode (820) to the transistor (814), the pace current of the transistor (81B) is cut off, and the transistor (814) is cut off. FIG. 8 is a characteristic curve showing changes in the adjustment voltage with respect to changes in ambient temperature according to the present invention, and FIG. 4 is a characteristic curve showing changes in resistance of the eleventh second heat-sensitive element with respect to changes in ambient temperature.

As described in detail above, in the present invention, when the temperature of the voltage regulator increases, the output limitation of the alternator is started at the high first predetermined temperature, and when the temperature of the voltage regulator decreases, the output limit of the alternator is started at the first predetermined temperature. By having a temperature control characteristic with hysteresis that maintains the output limit until a second predetermined temperature lower than the specified temperature, the output does not recover to the maximum allowable temperature for a short time at a temperature equivalent to the ambient temperature of the generator, This has the effect of improving stability and reliability without repeating intermittent interruptions at short intervals near the set temperature.

[Brief explanation of the drawing]

FIG. 1 is an electric circuit diagram showing a conventional device, FIG. 2 is an electric circuit diagram showing an embodiment of the present invention, FIG. 8 is a characteristic curve showing the operation of the present invention, and FIG. This is a characteristic curve of the heat-sensitive switching element used. In the figure, (1) is an alternating current generator, (101) is an armature coil, (102) is a field coil, (2) is a full-wave rectifier, (
3) is a voltage regulator, (!301) (816) (817
) (819) (820) are diodes, (802) (8
0g)<806)(814)(818) are transistors, (804)(808)(809)(811)(818
) (821) (828) are resistances, (806) (815
) is a Zener diode, (812) is a first heat-sensitive switching element, and (822) is a second heat-sensitive switching element. Note that the same reference numerals in the figures refer to the same or corresponding parts. Agent Shin Kuzuno −

Claims (1)

[Claims] The generator includes a storage battery charged by the rectified output of an alternating current generator having an armature coil and a field coil, and a semiconductor voltage regulator that controls a field current flowing through the field coil. a voltage detection circuit that detects the rectified output voltage of the battery and controls it to a first predetermined voltage value that is optimal for charging the storage battery; and a voltage detection circuit that detects a first predetermined temperature that is a short-time maximum allowable temperature of the voltage regulator 1 temperature detection circuit;
a second temperature detection circuit that detects a second predetermined temperature that is a maximum continuous allowable temperature lower than the first predetermined temperature, and the voltage regulator operates at the first predetermined temperature when the temperature rises; , the rectified output voltage of the generator is controlled to a second predetermined voltage value lower than the voltage of the storage battery, and when the temperature of the voltage regulator decreases, the rectified output voltage of the generator is controlled to a second predetermined voltage value until the voltage falls below the second predetermined temperature. A temperature-limited charging generator control device characterized by having temperature control characteristics with hysteresis to maintain a voltage value.