JPH0333200Y2 - - Google Patents

Description

[Detailed explanation of the idea]

(Industrial Application Field) This invention relates to a generator control device for an automobile that controls the power generation drive of a generator driven by an engine. (Prior Art) In recent years, in order to improve engine fuel efficiency, efforts have been made to make the idle flow rate leaner when the engine is idling. However, when the above-mentioned lean operation is carried out close to its limit, the engine speed during idling decreases, so the torque decreases, and if a sudden load is applied to the engine in this state, the engine will stop. There is a concern that this may occur. On the other hand, the alternator (generator) driven by the engine generates electricity even when idling, and at this time, field current is supplied to the field coil, which creates resistance to the rotation of the rotor. , the alternator will have a load on the engine. For example, if you apply sudden braking while driving and then disengage the clutch just before the vehicle speed drops and is about to stop, the engine torque will be small until the clutch is disengaged because the engine is forcibly driven by the rotational force from the wheels. Even if the alternator is dropped, it will not overload the engine, but when the clutch is disengaged, there is no forced drive from the wheels, so
The load of the alternator is suddenly applied to the engine, resulting in an overload and stopping the engine. Conventionally, a thermistor that electrically detects changes in the liquid temperature and level is installed in the battery liquid installed in automobiles, and when an abnormality is detected in the liquid, a device that lowers the voltage generated by the alternator (for example, in a practical application) Showa 55
-166069), but this device was a battery protection device and had no intention of reducing the load on the generator engine. (Purpose of the invention) The object of the invention is to provide a generator control device for an automobile that can prevent engine stoppage due to the load on the generator when the engine is idling. (Structure of the invention) This invention consists of a generator driven by an engine,
a regulator circuit that controls the generated voltage of the generator by controlling the field current supplied to the field coil; a brake sensor that detects that the brake is applied and emits an output signal X that is a high level signal; A clutch sensor that detects that the clutch is disengaged and generates an output signal Y that is a low level signal, and a timer that generates an output signal Z that is a high level signal only for a predetermined time in response to the output signal Y of the clutch sensor. element, and a logic circuit that outputs X and Z outputs obtained by performing logical operations on the respective output signals X and Z for only a predetermined time by a time-limiting element, and the output of the logic circuit is used to supply a field current provided to the regulator circuit. The present invention is characterized in that the present invention is connected to an active element for a motor vehicle, and is configured to reduce a field current of a field coil via the active element when the logic circuit outputs a low level signal. (Effect of the invention) According to this invention, when the brake is stepped on and the clutch is disengaged, these operations are detected by the brake sensor and the clutch sensor, and based on these detection outputs, the above logic is applied. The circuit outputs a low level signal of X・Z=1・1=1=0 only for a predetermined time by a time element to the active element in the above-mentioned regulator circuit, and via this active element to the field coil of the above-mentioned generator. The field current of the generator is controlled to decrease, thereby lowering the rotational resistance of the generator and reducing the load on the generator's engine. Therefore, even if the clutch is disengaged after sudden braking and the engine torque suddenly decreases, the load on the generator is reduced in response to this, so there is no overload, and as a result, the power is generated. Engine stoppage due to machine load can be reliably prevented. (Example) An example of this invention will be described in detail below based on the drawings. The drawing shows a generator control device for an automobile. In FIG. 1, a generator 1 is an alternator composed of an armature coil 2, a field coil 3, and a diode rectifier circuit 4. The generated voltage of the armature coil 2 is controlled under the control of the supplied field current, and the diode rectifier circuit 4 rectifies the induced electromotive force of the armature coil 2. A regulator circuit 5 is connected to the field coil 3 described above, and this regulator circuit 5 includes a drive transistor 6, an amplification transistor 7,
Power transistor 8, Zener diode 9,
Diode 10, surging prevention capacitor 1
1. It is composed of a variable resistor 12 and resistors 13 to 17, and when the generated voltage of the armature coil 2 is below a set value, the drive transistor 6 becomes non-conductive,
When the amplification transistor 7 and the power transistor 8 become conductive, a field current is supplied to the field coil 3, and the generated voltage exceeds the set value, the Zener diode 9 becomes conductive, the drive transistor 6 becomes conductive, and the amplification transistor 7 becomes conductive. Then, the power transistor 8 becomes conductive, and the field current supply to the field coil 3 is cut off. By controlling the field current supply in this manner, the generated voltage is controlled to the set value. The logic circuit 18 cuts off the field current supplied to the field coil 3 of the generator 1 when the brake of the automobile is depressed and the clutch is disengaged.
This is a control circuit to prevent the generator 1 from becoming a load on the engine, and the brake sensor 1
9 consists of normally open switches,
When the brake is pressed and activated, the switch is closed and detected, output signal X (see Figure 2)
The clutch sensor 20 is composed of a normally closed switch, and when the clutch is disengaged, the switch is opened and detected, and an output signal Y (see FIG. 2) is output. Here, the logic circuit 18 described above obtains an output as shown in the following truth table.

[Table] The specific configuration of the logic circuit 18 described above is as follows. That is, the logic circuit 18 described above has the first,
Second and third comparators 21, 22, 23, amplifier 2
4, diodes 25, 26, clutch sensor 2
It is composed of a capacitor 27 and resistors 28 to 40 as time-limiting elements that receive an output signal Y of 0 and generate an output signal Z which is a high level signal for a predetermined period of time.
is connected to be inputted to the non-inverting input terminal of the first comparator 21 via the above-mentioned clutch sensor 2.
The detection signal of 0 is connected to be input to the inverting input terminal of the second comparator 22, and the anode of the diode 26 connected to the card at the output stage of the third comparator 23 is connected to the amplifying transistor 7 of the regulator circuit 5 described above. is connected to the base side of the Note that the resistors 35 and 36 are voltage dividing resistors that set the reference value of the first comparator 21, and the resistors 33 and 3
4 is a voltage dividing resistor that applies a set current to the input for nozzle countermeasures. Further, resistors 30 and 31 are voltage dividing resistors that set a reference value for the second comparator 22, and resistors 28 and 29 are voltage dividing resistors that apply a set current to the input to prevent noise. Furthermore, the resistors 39 and 40 are voltage dividing resistors that set the reference value of the third comparator 23. In other words, the above-mentioned logic circuit 18 performs a logical operation on the above-mentioned output signals X and Z and outputs the output only for a predetermined time by the capacitor 27. The operation of the automobile generator control device configured as described above will be explained with reference to FIG. 2. Note that the symbol H in the figure indicates a high level, and the symbol L indicates a low level. During normal operation when the brake and clutch are not operated, the first and second comparators 21 and 22 and the amplifier 24 each receive a low level signal L (O signal).
The third comparator 23 outputs a high level signal H (1 signal), and the diode 26
is in a blocked state. When the brake is operated in this state, the brake sensor 19 is closed, and its detection signal (output signal X=1) is input to the first comparator 21.
This comparator 21 outputs a high level signal H. However, since the diode 25 is in the blocking direction, the third comparator 23 is not operated. When the clutch is operated while the above-mentioned brake is operated, the clutch sensor 20 is opened and its detection signal (output signal Y=0) becomes the second
The signal is input to a comparator 22, which outputs a high level signal H, and subsequently, an output terminal A of an amplifier 24 also outputs a high level signal H. When the above-mentioned output terminal A becomes high level, the third
Since the input terminal B of the comparator 23 (the signal at the input terminal B corresponds to the signal Z) is cut off by the diode 25, the capacitor 27 interposed between the terminals A and B begins to charge. During this charging time, the aforementioned input terminal B is at a high level, and while this signal exceeds the reference value of the third comparator 23, the output terminal C of this comparator 23 is at a low level. . That is, the signal at the output terminal C becomes =.=1.1=1-0. The above output terminal C is a low level signal (O signal)
When the diode 26 becomes conductive, the amplification transistor 7 of the regulator circuit 5
Since the current supplied to the base of is drawn to the third comparator 23 side, this transistor 7 becomes non-conductive,
The power transistor 8 also becomes non-conductive, the field current of the field coil 3 is cut off, and the field coil 3 is not excited. As a result, the rotational resistance due to the magnetic force of the field coil 3 is eliminated, the generator 1 enters an idle state, and the load on the engine can be eliminated. Therefore, after the car suddenly brakes,
If the clutch is disengaged just before stopping in this state, even if the engine torque decreases rapidly, the generator 1 will be idling with no load at the same time as the clutch is disengaged, so the engine will start running due to the load on the generator 1. Tops are prevented. Note that after the capacitor 27 mentioned above is charged, the inverting input terminal B of the third comparator 23 becomes a low level signal (O signal), so the output terminal C of this comparator 23 becomes a high level signal (1 signal). As a result, the diode 26 is cut off, the amplification transistor 7 is enabled to operate, and the regulator circuit 5 is operated in a normal state. When the generator 1 is returned to the generating state, the generator 1 becomes a load on the engine, but since the engine is in a stable idling state,
The above-mentioned loads do not cause engine stoppage. In the correspondence between the configuration of this invention and the embodiment described above, the time element of this invention corresponds to the charging/discharging circuit using the capacitor 27, and similarly, the active element corresponds to the amplification transistor 7 in the regulator circuit 5. However, the present invention is not limited to the configuration of the above-described embodiment. For example, in the embodiment described above, the logic circuit 18 controls the field current by cutting it off, but it may control the field current to reduce it.

[Brief explanation of drawings]

The drawings show one embodiment of this invention, and FIG. 1 is an electric circuit diagram showing a generator control device for an automobile, and FIG. 2 is a time chart. 1... Generator, 3... Field coil, 5...
...Regulator circuit, 7...Amplifying transistor, 18...Logic circuit, 19...Brake sensor, 20...Clutch sensor, 27...Capacitor.

Claims (1)

[Claims for Utility Model Registration] A generator 1 driven by an engine, a regulator circuit 5 that controls the generated voltage of the generator 1 by controlling the field current supplied to the field coil 3, and a brake applied. a brake sensor 19 that detects that the clutch is disengaged and issues an output signal X that is a high level signal; a clutch sensor 20 that detects that the clutch is disengaged and issues an output signal Y that is a low level signal; In response to the output signal Y of the sensor 20, the output signal Z is a high level signal only for a predetermined period of time.
and a logic circuit 18 that performs a logical operation on each of the output signals X and Z and outputs the output only for a predetermined time by the timer element 27. The output of the logic circuit 18 is connected to the regulator circuit 5. An automobile generator control device is connected to an active element 7 for supplying field current provided in the circuit 1, and configured to reduce the field current of the field coil 3 via the active element 7 when the logic circuit 18 outputs a low level signal. .