JPH0347058B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an alternator control device used in an engine of an automobile or the like.

[Prior Art] In modern automobiles, it is common to use an alternator in the battery charging system, and to adjust the output voltage of the alternator using an IC regulator.

Note that the conventional IC regulator has its power input terminal connected to the driving power source (battery) via the engine switch (ignition switch), and once the engine switch is turned on, the IC regulator is always connected to the power source. Driving power is now supplied. Therefore, the power generation function of the oil generator is stopped only when the voltage at the charging terminal of the alternator, in other words, the voltage of the battery connected to this charging terminal exceeds a preset adjustment voltage. It will be done.

By the way, since the alternator is driven using part of the engine's power,
The load on the engine is different when the alternator is generating electricity and when it is not generating electricity. Therefore, if only the above-mentioned control is performed, the load on the alternator may adversely affect driveability, fuel economy, etc. Therefore, there is a desire to be able to control the alternator appropriately in response to various load conditions.

However, as a prior art technique that meets these demands, there is a technique that can reduce the amount of power generated by the alternator during acceleration, as shown in Japanese Utility Model Publication No. 14048/1983. However, the idea disclosed here is to give a signal inside the regulator,
The idea is to reduce the amount of power generated by the alternator when the signal is supplied. Therefore, when implementing this method, it is necessary to change the circuit inside the regulator, and there is a problem in that it costs a lot of money to apply it to an IC regulator.

Therefore, recently, the power input terminal of the IC regulator is connected to the operating power source through a switching means provided separately from the engine switch, and the battery voltage is set to a set value (the adjustment voltage (lower value) than
An alternator control device has been proposed in which the switching means is temporarily switched to a non-energized state to forcibly stop power generation of the alternator when a predetermined load condition is met.

[Problems to be Solved by the Invention] However, with just this, there is a problem in that hunting occurs in the alternator control immediately after starting the engine at low temperatures. That is, when the battery is cold, the functionality of the battery is reduced, so if the alternator stops generating electricity, the battery voltage may immediately drop below the set value. In this case, as soon as the above-described certain conditions are met and the alternator stops generating electricity, the battery voltage drops to the set value and the alternator starts generating electricity again, which is repeated in a short period of time. As a result, a surge voltage is generated.
This tends to cause the inconvenience of destroying the transistor in the IC regulator.

To deal with this kind of inconvenience, it is possible to prohibit the above-mentioned alternator control until a predetermined time has elapsed after engine startup or until the engine cooling water temperature exceeds a predetermined temperature. Since the settings have to be made in accordance with the worst conditions, there is a problem in that the operating range in which the alternator can be stopped is unduly confined.

The present invention aims to solve all of these problems.

[Means for solving the problems] In order to achieve the above objects, the present invention has the following features:
An alternator 1 that is driven by the engine A to generate electricity, an IC regulator 2 that adjusts the output of the alternator 1, and an IC regulator 2 that is driven by the engine A to generate electricity.
A switching means 6 interposed between the power input terminal IG of the engine and the drive power source 3 disables the switching means 6 only while the battery voltage exceeds a set value and a predetermined engine load condition is met. A power generation cut means B that switches to the energized state and stops the power generation function of the alternator 1, a water temperature sensor 14 that detects the cooling water temperature of the engine A, and a signal from the water temperature sensor 14 that detects the cooling water temperature value at the time of starting the engine. a time setting means C that sets a cutting prohibition time according to the value; and a time setting means C
and a cut prohibition means D which unconditionally prohibits the power generation cut means B from switching the switching means 6 to the non-energized state until the cut prohibition time determined by the cut prohibition time has elapsed. do.

[Function] According to such a configuration, the cut prohibition time is set according to the temperature at startup, and the IC regulator is disabled until the cut prohibition time elapses regardless of whether the control conditions are satisfied or not. The alternator control in which the switching means 6 is switched to a non-energized state and the power generation function of the alternator is stopped is prohibited. Therefore, as long as the optimal cut prohibition time is carefully set in advance for each starting temperature, the operating range in which the alternator control is prohibited can be kept to the necessary minimum.

[Embodiment] Hereinafter, an embodiment in which the present invention is applied to a battery charging system of an automobile will be described with reference to FIGS. 2 to 4.

FIG. 2 is a diagram showing an embodiment of an alternator control device according to the present invention, in which 1 indicates an alternator;
2 is an IC regulator, 3 is a battery, 4 is an electrical load, 5 is an engine switch, 6 is a transistor serving as a switching means, and 7 is an electronic control device that turns ON/OFF the transistor 6.

The alternator 1 is configured by providing a rotor winding L _f to three stator windings L _{1 to} L ₃ that are connected in _a three-phase star shape. Diode bridges D ₁ to _{D 6} are provided in each phase, and the induced voltage induced in the stator windings L ₁ to _{L 3} is full-wave rectified and output. The charging terminal B is connected to the battery 3.

Further, the IC regulator 2 is configured to control ON/OFF of two transistors T _r 1 and T _r 2, and performs a known regulation operation by turning one transistor T _r 1 ON/OFF. That is, in the embodiment, by turning on the transistor T _r 1, an excitation current is caused to flow through the rotor winding L _f of the alternator 1, and the stator winding of the alternator 1 is
Current is induced in L ₁ to _{L 3} to generate electricity, and the charge lamp F is turned on by turning on the other transistor T _r 2. In addition, two diodes installed in parallel with diode bridges D ₁ to _{D 6}
The series-connected body G consisting of D ₇ and D ₈ is a neutral point diode, which reduces potential fluctuations that occur at the neutral point of the stator windings L ₁ to L ₃ when the alternator 1 operates, and uses energy effectively. The aim is to The power input terminal IG of this IC regulator 2 is connected to the battery 3 which is a driving power source through the transistor 6, and the transistor 6 is turned on and off by the output signal of the electronic control device 7. There is.

That is, the electronic control device 7 includes a central processing unit 7a, a storage device 7b such as ROM or RAM,
Interfaces 7c, 7d for input and output
The power supply terminal 8 is connected to the battery 3 via the engine switch 5. The input interface 7c of the electronic control device 7 includes at least a vehicle speed sensor 9,
Signals and battery voltage from rotation detection means 11, starter switch 12, idle switch 13, and water temperature sensor 14 are respectively input. The rotation detection means 11 is for detecting the actual engine rotation speed, and uses, for example, an ignition pulse. Also,
The starter switch 12 is an ON/OFF switch for starting the engine starter. The idle switch 13 is an ON/OFF switch for detecting whether a throttle valve of a carburetor (not shown) has returned to a closed position. The water temperature sensor 14 is for detecting the cooling water temperature of the engine A, and includes, for example, a thermistor that converts the cooling water temperature into an analog electrical signal, and an A/D converter (not shown) that converts the output of this thermistor into a digital signal. ).

This electronic control device 7 has the following program built in, and this electronic control device plays the roles of the power generation cut means B, time setting means C, and cut prohibition means D described above. It's summery. That is, as shown in FIG. 3, this program first inputs signals from the rotation detecting means 11 and the starter switch 12 in step 51, and determines whether or not the engine is stopped in step 52. In step 53, it is determined whether the starter switch 12 is ON. If it is determined that the engine A is not stopped and the starter switch 12 is ON, that is, it is cranking, the process proceeds to step 54 and the coolant temperature of the engine A is input. Then,
In step 55, a cutting prohibition time t is set in accordance with the water temperature value. The setting of this cut prohibition time t is determined by selecting the optimum time corresponding to each engine cooling water temperature at the time of startup in advance through experiments and creating a map as shown in Fig. 4. This is done by appropriately selecting a specific cutting prohibition time t based on the following. As is clear from this drawing, this cutting prohibition time t
becomes longer as the cooling water temperature at startup is lower, and converges to zero at higher cooling water temperatures. After setting the cut prohibition time t in this manner, the increment counter Q is cleared in step 56 and time measurement is started. Next, in step 57, it is determined whether the value of the increment counter Q has counted up to a value exceeding the cut prohibition time t, and only if it has counted up, the process advances to step 58. In step 58,
Information necessary for alternator control, that is, signals from vehicle speed sensor 9, idle switch 13, and water temperature sensor 14, and battery voltage are input, and alternator control is performed in step 59.

The outline of alternator control is as follows.
In other words, the engine is not in a stopped state. The alternator remains ON for a certain period of time.
Idle switch 13 is OFF. Water temperature is 20℃ or higher. The battery voltage is greater than or equal to the predetermined upper limit setting value Vcut. Acceleration is being judged (vehicle speed is +2.1km/
When all the conditions are satisfied (the voltage has become larger than h), the transistor 6 is turned off.
Cut off the drive power to IC regulator 2.

Then it came to a standstill. Idle switch 13 was turned on. The water temperature has fallen below 15℃. The battery voltage has fallen below the predetermined lower limit setting value V _RT . When any of the conditions that the acceleration determination state is canceled is satisfied, the transistor 6 is turned on and the energization to the IC regulator 2 is restarted.

Note that the routine shown in FIG. 3 is repeatedly executed while the engine switch 5 is ON.

Next, the operation of this embodiment will be explained. When the engine switch 5 is turned on, the transistor 6, which is the switching means, maintains the energized state.
A voltage from a battery 3 serving as a driving power source for the IC regulator 2 is applied to the IG terminal of the IC regulator 2. Therefore, the IC regulator 2 detects this state and drives the transistor T _r 1. When the transistor T _r 1 is driven, the voltage of the battery 3 is applied to the rotor winding L _f , an excitation current flows, and a field is formed in the alternator 1. However, in this state, the engine is not rotating, so
Alternator 1 does not generate electricity, so the voltage at the P terminal is at ground level. As a result, when the IC regulator 2 detects this state, the transistor T _r 2 is driven to light the charge lamp F to notify that the battery power supply is being discharged.

From this state, when the starter switch is turned ON to start cranking, the control shown in Fig. 3 proceeds in steps 51→52→53→54→55, and a cut prohibition time t is set according to the engine cooling water temperature. Ru. Then, when the engine is started and the cranking switch is turned off, the control shown in FIG. 3 proceeds in steps 51→52→53→57, so that the increment counter Q starts counting time. That is, the counter value Q increases sequentially from zero as time passes. Thereafter, the process continues in step 57 until the cut prohibition time t has elapsed.
Since the process does not proceed from step 58, alternator control is not performed. Therefore,
The transistor 6 is maintained in the ON state, and the IC regulator 2 performs a normal regulating operation based on the regulated voltage. In addition, when cold, T _r1
is kept ON and power generation continues.

In this state, when the cutting prohibition time t elapses,
The control shown in FIG. 3 is performed in steps 51→52→53→
By progressing from 57 to 58 to 59, alternator control by the electronic control device 7 is started.
That is, when the electronic control unit 7 determines that the above-mentioned alternating conditions are satisfied, the transistor 6 is switched to a non-energized state. As a result, the IG terminal of IC regulator 2 has a drive power supply,
In other words, power supply from the battery 3 is stopped. As a result, the function of the IC regulator 2 is stopped and the transistor T _r1 is turned off, so the excitation current supplied to the rotor winding L _f of the alternator 1 is stopped, and the alternator 1 stops its power generation function. This state will continue until one of the certain release conditions is met, such as when the acceleration of the vehicle falls below the set value, and during that time the power generation of alternator 1 is forcibly stopped, so the load on the engine is reduced. be done.

As described above, the supply of drive current to the IC regulator 2 is cut off by switching the switching means 6, which is provided separately from the engine switch 5, to the non-energized state. Moreover, even when the battery voltage does not exceed the adjustment voltage, the function of the IC regulator 2 can be stopped and the power generation of the alternator 1 can be stopped.

Therefore, the power generation function of the alternator 1 can be stopped in the above-described desired operating range without changing any circuit inside the existing IC regulator.

Moreover, when the engine is started, the alternator control performed by switching the switching means 6 to the de-energized position is prohibited until the cut prohibition time t elapses, so there is no risk of the aforementioned control hunting occurring. It is possible to reliably prevent transistor wave damage accidents of the IC regulator 2.

Furthermore, since the cut prohibition time t is appropriately set depending on the temperature of the engine cooling water at the time of startup, the cut prohibition time t is lengthened at low temperatures to set temperature conditions that are less likely to cause hunting in the control. In this case, the cut prohibition time t can be shortened. Therefore, the operating range in which alternator control can be performed can be set as wide as possible, and drivability and fuel economy can be reasonably and effectively improved.

Note that the switching means is of course not limited to transistors, and the means for turning on and off the switching means is also not limited to microcomputer-type electronic control devices.

Further, in the above embodiment, the condition that acceleration is being determined is adopted as the predetermined engine load condition, and the alternator's power generation function is stopped when the vehicle accelerates. Of course, it is also possible to control the system so that it is paused. Examples of other operating ranges include a so-called partial lean operating range. In other words, the partial lean operating range means that the vehicle is running steadily under a light load, so the feedback control of the feedback cab system is temporarily interrupted to control the air-fuel ratio of the air-fuel mixture slightly to the lean side. This refers to the operating range where the vehicle is operated.

[Effects of the Invention] As detailed above, the present invention forcibly stops the power generation function of the alternator by temporarily cutting off the drive power supplied to the IC regulator. It is possible to reliably and precisely perform control to temporarily remove engine load by the alternator in a desired operating range. Moreover, the cut prohibition time is set according to the engine cooling water temperature at the time of starting, and the alternator control is prohibited until the cut prohibition time has elapsed, which unduly narrows the alternator control range and impairs drivability. It is possible to reasonably and effectively prevent control hunting during a cold start, etc., without deteriorating fuel economy.

[Brief explanation of drawings]

FIG. 1 is a configuration explanatory diagram for clearly explaining the present invention. 2 to 4 show an embodiment of the present invention, FIG. 2 is a system explanatory diagram, FIG. 3 is a flowchart showing an overview of control, and FIG. 4 is for explaining control setting conditions. FIG. A... Engine, B... Power generation cut means, C... Time setting means, D... Cut inhibiting means, 1... Alternator, 2... IC regulator, 3... Drive power source (battery), 6... Switching means (transistor),
14...Water temperature sensor.

Claims (1)

[Claims] 1 Adjust the alternator that is driven by the engine to generate electricity and the output of this alternator.
An IC regulator, a switching means interposed between a power input terminal of the IC regulator and a drive power source, and a switching means that operates only while the battery voltage exceeds a set value and a predetermined engine load condition is satisfied. A power generation cut means for switching the means to a de-energized state to stop the power generation function of the alternator, a water temperature sensor for detecting the engine cooling water temperature, and a signal from the water temperature sensor to detect the cooling water temperature value at the time of starting the engine. a time setting means for setting a cut prohibition time according to the cut prohibition time; and a cut for unconditionally prohibiting the power generating cut means from switching the switching means to a non-energized state until the cut prohibition time determined by the time setting means has elapsed. An alternator control device comprising: inhibiting means.