JPH025075Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The present invention is a turbo engine that continues idling for a predetermined period of time even after the ignition switch is turned off, in order to prevent the turbo turbine from seizing up. - Concerning improvements to idling delay devices for vehicles equipped with charge gears.

<Conventional Technology> Recently, vehicles equipped with a turbo charger have become quite popular. The turbine used in this turbo charger rotates at extremely high speeds of 100,000 to 150,000 revolutions per minute while the vehicle is running, and its temperature reaches over 900 degrees Celsius.

In order to cool these turbines, in cars equipped with this type of turbo charger, engine oil is supplied cyclically to the turbine using an oil pump, but when the ignition switch is turned off and the engine stops, the oil is The pump will also stop.

Therefore, especially if you have been driving with the turbo activated and then stop immediately and immediately turn off the engine, the turbine will continue to rotate somewhat due to inertia, so the engine will stop as described above. If the oil supply was cut off immediately, there was a risk that seizure might occur.

In view of these points, the applicant of the present invention has previously devised a circuit as a countermeasure as shown in FIG.

The circuit shown in FIG. 5 keeps the engine idling for a set period of time even after the ignition switch is turned off, and its operation is as follows.

When a normal ignition switch 2 interposed in the power line from a vehicle-mounted battery 1 to a known existing engine drive device 4 is opened, a trigger pulse is sent from the #1 trigger device 11, and the control device receives the trigger pulse. A drive current is passed from the circuit 9 to the driver transistor 6 of the interrupter 3.

As a result, when the interrupter 3 operates and its make contact 3a is closed, driving power is still supplied to the engine drive circuit 4 through the path including this contact 3a, even though the ignition switch 2 is turned off. , the engine still continues to rotate.

However, at the same time as the start of supply of drive current to the interrupter driver transistor 6, a start signal is also given to the timer circuit 5 from the control circuit 9, so the timer 5 starts measuring time from this point. ing.

When the time set in this timer has elapsed, the #2 trigger circuit 10 generates a second trigger pulse due to the time-up pulse from the timer. The drive current sent to the device driver transistor 6 is stopped, and the timer is reset.

Therefore, the make contact 3a of the interrupter 3 opens and the engine stops at that point.

Considering the above operation, the circuit shown in FIG.
It can be seen that the engine has a function that allows the engine to continue to rotate even after the ignition switch is turned off.

Therefore, the delay time in the delay function described above is most simply fixed at a certain specific time, but as a slightly more practical form, as shown in Figure 5, multiple delay times can be set. Some vehicles are equipped with time setting switches Sa, Sb, Sc, and Sd, and the driver can selectively operate these switches to set the time in several stages.

Further, in order to reliably stop the engine when the control system does not operate as specified, a protection circuit 7 may be provided in addition to the above configuration.

This protection circuit 7 receives a time signal from the timer circuit 5.
If the break contact 3b of the interrupter 3 is not opened even though the up pulse has been output, it is assumed that this is an abnormal situation in which drive current is still being supplied to the driver transistor 6, and the switching transistor 8 is turned off. This is to forcibly cut off the driver transistor 6 by, for example, causing the base of the driver transistor 6 to be grounded.

<Problems that the invention attempts to solve> In conventional idling delay devices like the one described above, whether it is fixed or can be set variably in several stages, the The timer setting time is independent of the turbine condition.

Therefore, for example, even if the turbine temperature is sufficiently low that there is no risk of the turbine seizing up even if the engine is stopped immediately, the engine will not stop until the set time has elapsed.

Therefore, if the set delay time is fixed, the time must be set assuming that the turbine is at its hottest state, so when the turbine is not that hot, the engine may not run for a long time. You will end up continuing to spin it in vain.
This is contrary to the current trend of trying to maintain good fuel consumption rates.

On the other hand, in the case of a system in which the set time is made variable by the operator, as shown in Figure 5, the above-mentioned drawbacks are largely eliminated because the operator can set the time that is considered optimal at any given time depending on the turbine condition. It will be reduced.

However, this setting is made by the operator, and considering that the operator cannot reliably grasp the actual turbine status at any given time and relies on intuition, it is not practical. It cannot be said that it is a completely satisfactory device.

It is quite difficult to always remember the driving situation immediately before turning off the ignition switch and choose the most appropriate switch according to that situation.
It's also a hassle. If an unnecessarily long time is selected by mistake, the delay time will be no different from the case described above where the delay time is set to a fixed value.

The present invention was developed based on this viewpoint, and it electrically monitors the condition of the turbine, correlates the turbine condition with the time set in the timer circuit, and optimizes the idling delay time for the turbine condition at that time. The aim is to provide a device that can automatically set the

Furthermore, this invention focuses on the fact that there is a deep correlation between the temperature of a turbine and the amount of time the turbine has been in operation, and the longer the time the turbine has been in operation, the higher the temperature. This mechanism automatically sets the optimum or shortest idling delay time depending on the length of time the turbine was operating before the engine was turned off, ensuring that the turbine is running at a good rate while maintaining a good fuel consumption rate. The purpose is to protect them.

<Means for Solving the Problems> In order to achieve the above-mentioned purpose, the present invention has been developed for vehicles equipped with a turbo charger that keeps the engine idling for a period of time set in the timer circuit even after the ignition switch is turned off. The idling delay device comprises: a circuit for measuring the operating time of the turbine of the turbo charger; and a timer time setting circuit for varying the time set in the timer circuit according to the measured turbine operating time; An idling delay device is provided.

<Operation> As in the above configuration, measuring the time during which the turbine was operating means equivalently measuring the turbine temperature. Therefore, conversely speaking, the higher the turbine temperature, the longer the turbine operating time measured by the operating time measuring circuit, and the lower the turbine temperature, the shorter the turbine operating time.

In this way, based on the results of measuring the turbine operation time, the device of the present invention uses the timer time setting circuit to determine the engine idling time as a necessary and sufficient short time according to the time length. Automatically set at that time.

Therefore, the operator does not need to pay particular attention to the temperature condition of the turbine at any given time.

In addition, the method of variable setting of time may be an analog method in which the time is continuously set variably according to the detected turbine operating time length, or the turbine operating time length is divided into several step ranges and each step A digital method may also be used in which an appropriate timer time is set for each time.

<Embodiment> FIG. 1 shows a preferred embodiment of the vehicle idling delay device of the present invention. In the figure, the components with the same reference numerals as those in FIG. 5 described above indicate components that may be the same or similar to those in the conventional example. Therefore, the circuit portion on the right hand side in FIG. 1 is a group of manual switches for setting the timer time of the timer circuit in the conventional circuit shown in FIG.
It has almost the same configuration as that except for Sa to Sd. The characteristic circuit part of this invention is the first
In the figure, this is the circuit part on the left.

In the circuit part provided according to the present invention,
When measuring the operating time of a turbo charger turbine, the following circuit system is first installed for preprocessing.

This invention is intended for use in vehicles where the turbo is activated at a specific engine speed or higher (for example, 3000 rpm or higher), so whether or not the turbo is in operation can be determined based on the engine speed. It has a determination unit 21 that makes a determination. For this purpose, engine rotation speed information is extracted, and in this embodiment, that information is obtained based on a spark ignition signal as shown in the second diagram, which is generated at the negative terminal 25 of the ignition coil.

That is, after the spark ignition signal waveform-shaped by the waveform shaping circuit 24 is further converted into a regular pulse as shown in the second figure by the one-shot pulse generation circuit 23, the frequency-to-voltage (F-V) conversion circuit 2
2, and as the output of this frequency-to-voltage conversion circuit 22, a DC voltage value approximately proportional to the engine rotation speed as shown in FIG. 3 is obtained.

Therefore, the rotation speed at which the turbo becomes effective (in Figure 3,
The corresponding voltage value at point Ra) is the reference voltage value Es
This reference voltage value Es and the output voltage value of the frequency-to-voltage conversion circuit 22 are determined by the turbo operation determination unit 2.
If compared with the comparator 21a in 1, the reference voltage value
When Es is input to the negative phase input side, the corresponding comparator 2
When the output of 1a shows logic "H", it can be determined that the turbo is working.

After performing such pre-processing, the output logic value of the turbo operation determination unit 21 is monitored, and the time period during which the logic value indicates logic "H", that is, the turbo operation determination section 21 is monitored.
A time measurement circuit 20 measures the operating time of the turbine.
Measure at

This turbine operating time is also measured as a voltage in this embodiment, and in particular, the capacitor 2
It is measured as the potential across 0b.

That is, when the turbo operation determination section 21 detects the operation of the turbo, the output of the comparator 21a becomes logic "H" as described above, so that the gate or analog switch 20c is opened, and the power supply voltage is The capacitor 20b is charged with an appropriate time constant. In this way, the potential across the capacitor 20b will rise in accordance with the length of time that has elapsed since the output logic value of the turbo operation determination unit 21 became "H", that is, after the turbo started operating. . These relationships are also shown in FIGS. 3B and 4A-D.

However, in this embodiment, due to circuit considerations, the potential across the capacitor is not handled directly, but is once introduced into the operational amplifier 20d, which lengthens the elapsed time, as shown in FIGS. 3C and 4E. It is converted into an inverted waveform in which the voltage value decreases according to .

The output voltage signal of such time measurement circuit 20 is
Then, as described below, the measured turbine operating time is input to a plurality of comparison circuit groups at a predetermined sample timing over a predetermined sample time Ts.
It is determined which length range Tx falls into.

In this embodiment, the comparison circuit #1 to #3
The detected turbine operating time is therefore compared with three reference times. Each hour is
As mentioned earlier, it is converted into a corresponding voltage signal and handled, so if the output potential of the time measurement circuit 20 is Ex, this potential Ex is
Reference potential to threshold potential E1, #2 comparison circuit 17
Reference potential E2 of #3 comparison circuit 18, reference potential E3 of #3 comparison circuit 18
are compared with each other. In this embodiment, the magnitude relationship of the reference potentials of the three comparison circuits 16 to 18 is as follows.
It is also shown in Figure C. That is, E1<
E2<E3.

An example of the operation of this circuit under such a circuit configuration will be explained.

When the ignition switch 2 is turned off, as shown in FIG. A trigger pulse is generated which goes to logic "L" for a period of time and then returns to logic "H" again.

This trigger pulse is applied to one input of a control circuit 9 composed of a flip-flop, and produces a logic "H" output at the output terminal 9a.

This turns on the driver transistor 6 of the interrupter 3 and closes the make contact 3a of the interrupter.
is injected. Therefore, driving power is supplied from the existing battery 1 mounted on the vehicle to the known existing engine drive device 4 through this make contact 3a, and even though the ignition switch is turned off, the engine still rotates. continue.

At the same time, the other output in the control circuit 9 is logic “H”
As the signal changes from "L" to "L", the timer circuit 5 operates at the falling edge and starts measuring time.

The timer circuit 5 makes the set time To variable according to the input information received at the time setting input terminal Pi (in this embodiment, the resistance value of the time setting resistor).
This point will be explained later, but here it is assumed that a certain set time To is given, and as the set time elapses, the output of the timer circuit 5 becomes as shown in FIG. 4N. A single time-up pulse appears like this.

This time-up pulse causes the #2 trigger circuit 10 to generate a second trigger pulse, as shown in FIG. It works to reverse the logical value relationship.

Therefore, the conductive driver transistor 6 is turned off, and the make contact 3a of the circuit breaker opens as shown in FIG. stops.

If the drive current continues to be supplied to the base of the driver transistor 6 despite the time-up pulse being output, it is desirable to install two NANDs at the input section of the protection circuit 7. - Since all inputs 7a, 7b, 7c of the gate are now at logic "H", output 7d is at logic "H" and transistor 8 is turned on.

As a result, the base of the driver transistor 6 is forced to ground, which forces it to turn off and also forces the make contact of the interrupter to open.
Reliable engine stop is guaranteed.

Below, after resetting the ignition switch,
Each time the power is cut off again, the above operation is repeated in the same way.

Therefore, in the device of the present invention, in order to set the timer circuit 5 optimally each time, as the trigger pulse appears at the output of the #1 trigger circuit 11 after the ignition switch is shut off, the above-mentioned circuit section The following actions occur.

The analog switch or gate 20e in the time measuring circuit 20 is opened via the inverter 20f by the trigger pulse going to the logic "L" level of the #1 trigger circuit 11 described above. The open time of this gate is the time Ts during which the trigger pulse is at logic "L", and therefore, this time Ts is the turbine operating time Tx measured by the time measuring circuit 20.
The sample time is Ts.

When the gate 20f opens, a voltage value representing the length of the turbine operation time Tx up to that point is generated.
Ex is from the time measurement circuit 20 to each comparison circuit 1 described above.
It is given to the inverting inputs 6 to 18.

Here, as shown in Fig. 3C, the turbine operating time Tx from the function start time ta at a specific engine speed Ra is between two reference times T3 and T2, and T3<Tx<T2. Assume that the output voltage value Ex of the time measurement circuit 20 satisfies E2<Ex<E3.

Under these assumed conditions, as shown in Figure 4 H, I, and J, the reference potential E1 is lower than this potential Ex.
The output of the #1 comparator circuit 16 and #2 comparator circuit 17 inverts to logic "L" and returns to logic "H" after the sample time Ts has elapsed, while having a reference potential E3 higher than the potential Ex. The output of #3 comparison circuit 18 maintains logic "H".

Therefore, the flip-flop circuits 13a and 14a provided in the #1 timer time setting circuit 13 corresponding to the #1 comparison circuit 16 and the #2 timer time setting circuit 14 corresponding to the #2 comparison circuit 17 respectively The state is reversed, the output is set to logic "H", and this output logic opens the corresponding gates 13b and 14b as shown in FIG. 4 K, L, and M.

As a result, each time setting circuit 13, 14, 15
Of the time setting resistors 13c, 14c, and 15c inside, the resistors 13c and 14c are connected in parallel between the time setting information inputs Pi and Pi of the timer circuit, so that the timer corresponds to this parallel combined resistance value. The time will be set to

Similarly, for example, if the detected operating time Tx of the turbine is shorter than the shortest reference time T3, the corresponding detected potential Ex will be set to the third reference potential.
Since it is larger than Ex, three resistors 13c~
All parallel combined resistance values of 15c are given to time setting information inputs Pi, Pi, and are set to the shortest scheduled time. Conversely, when the time is longer than the reference time T2, the detected potential Ex exceeds only the first reference potential E1, so only the resistor 15c is involved in setting the time of the timer 5, and is set to a longer time.

Based on the time thus set, the timer circuit 5
As mentioned above, the trigger pulse appears at the output of the #2 trigger circuit 10 due to the appearance of the time-up pulse.
This pulse is also used as a reset pulse for the internal flip-flops 13a to 15a of each timer time setting circuit 13 to 15.
9 is also applied to the inverter 19a, and the buffer 1
The transistor 19c for discharging the capacitor stored charge is turned off via the capacitor 9b, and the capacitor 2
It is also used to return 0b to its initial state.

Therefore, if the ignition switch is turned on again and the vehicle is driven, and then the ignition switch is turned off again after finishing business, the same operation as the above-mentioned time setting operation will be repeated again. An appropriate timer time setting is made depending on the length of the turbine operation time Tx used in one run.

In this embodiment, the detection time range is divided into four groups using three threshold values, but this number can be increased or decreased as desired as long as it is two or more. In some cases, it is also possible to achieve stepless time variable setting in an analog manner by employing an analog electronic volume.

In addition, the engine speed is extracted to determine whether the turbo is working or not, but it can be extracted by any method other than the one shown in the diagram, and depending on the case, it can be obtained in most of the rotation speed range. When targeting a vehicle that operates with a turbo, it may be possible to eliminate the need for the determination unit 21. In any case, the illustrated circuit configuration itself is merely an example, and is by no means limited to this.

<Effects of the Invention> According to the invention, the engine idling time after turning off the ignition switch can be automatically and variably set by correlating with the turbine operation time of the turbo charger.

Therefore, the conventional disadvantage of keeping the engine idling uniformly for a long time even though the turbine has been operating for a short time and the temperature has not risen significantly is avoided, and fuel consumption is minimized. can be suppressed to

Furthermore, since the operator does not have to worry about the operating time of the turbine or the delay time at which its temperature is optimal, the operator can avoid complicated operations. Of course, as usual with conventional manual settings,
There is no risk of misconfiguration, which often occurs.

[Brief explanation of the drawing]

FIG. 1 is a schematic circuit diagram of a preferred embodiment of the vehicle idling delay device of the present invention, FIG. 2 is an explanatory diagram for obtaining engine speed information, and FIG. Characteristic diagram of an example of the relationship between turbine operating time and each converted voltage, 4th
The figure is a waveform diagram of each part explaining the operation of the first illustrated circuit device, and FIG. 5 is a schematic configuration diagram of a conventional idling delay device for a vehicle. In the figure, 1 is the battery, 2 is the ignition switch, 3 is the interrupter, 4 is the engine drive device, and 5 is the ignition switch.
is a timer circuit, 6 is an interrupter driver transistor, 7 is a protection circuit, 9 is a control circuit, 10, 11
1 is a trigger circuit; 13, 14, and 15 are timer time setting circuits; 16, 17, and 18 are comparison circuits; 20 is a turbo turbine operation time measurement circuit; 21 is a turbo operation determination unit; and 22 is a frequency-to-voltage conversion circuit. ,2
5 is the negative terminal of the ignition coil.

Claims (1)

[Scope of Claim for Utility Model Registration] An idling delay device for a vehicle equipped with a turbo charger that continues to idle the engine for a period of time set in a timer circuit even after the ignition switch is turned off. An idling delay device comprising: a circuit that measures a turbine operating time; and a timer time setting circuit that changes the time set in the timer circuit according to the measured turbine operating time.