JP3136513B2 - Engine start control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine start control device for automatically starting an engine and performing an idling operation.

[0002]

2. Description of the Related Art The interior of an automobile immediately after the start of an engine is hot in summer and particularly freezing in winter morning.
In order to eliminate such driver discomfort, there is an increasing demand for an engine start control device that automatically starts an engine and performs an idling operation without operating an ignition switch of a vehicle.

[0003] Such an engine start control device sends a starter motor drive circuit to a starter motor drive circuit when the time set in a timer has elapsed, when the time set in the timer has elapsed, or when a radio signal emitted by a remote control operation has been received. Electric power is supplied to drive the starter motor to perform cranking, and thereafter, when the engine is started, the operation is continued in an idling state for a certain time.

As means for recognizing whether or not the engine has started, a method of detecting a difference between the battery voltage before cranking and a battery voltage after cranking, and a method in which the alternator starts power generation when the engine starts, thereby obtaining a signal Alternator L terminal where rises (hereinafter referred to as "L terminal")
And a method of detecting the voltage of

The method of detecting the difference between the battery voltages is as follows. The battery voltage after cranking, that is, the voltage when the engine is started, is the voltage before cranking, Since the voltage becomes higher than the voltage when the engine is not started, if a certain difference between the two is detected within a certain time, it is recognized that the engine has started. Further, the method of detecting the voltage of the L terminal is such that the L terminal voltage when the engine is not running is a small voltage, whereas when the engine is started and power generation is started by the alternator, the L terminal voltage is thereby detected. Since the voltage rises, when it is detected within a certain time that the L terminal voltage becomes equivalent to the battery voltage, it is recognized that the engine has started.

[0006]

However, among the above-mentioned recognition means, in the former method, various factors on the vehicle side,
For example, depending on the battery capacity, the state of the battery, the amount of power generated by the alternator, etc., the amount and time of increase of the battery voltage are various, but the determination conditions are set to some extent uniformly, and the cranking time is constant. Since the rise difference is detected after the lapse of time, there has been a case where the engine cannot be recognized even though the engine is started. Therefore, the cranking by the starter motor is performed continuously for an unnecessarily long time, and the battery power is wasted.

In the latter method, when the rise of the voltage at the L terminal can be detected, the time point of starting the engine can be almost surely recognized. However, the wiring from the L terminal of the alternator exists in a place where the L terminal is very complicated. Therefore, special wiring is required, and the wiring requires time and is a difficult operation.

[0008] The present invention has been proposed in view of the above,
An object of the present invention is to provide an engine start control device capable of recognizing the start of an engine quickly and in a timely manner and without special wiring for recognizing the start of the engine.

[0009]

According to the present invention, there is provided an engine start control apparatus for automatically starting an engine to perform an idling operation.
Start command signal output means for outputting a start command signal to the engine; start-related equipment command means for instructing a start-related device to perform a predetermined operation based on the start command signal; and battery voltage to a starter based on the start command signal A starter drive commanding means for instructing and driving the application; and monitoring the fluctuation cycle of the battery voltage and switching from cranking to engine start when detecting that the fluctuation cycle of the battery voltage is continuously shortened over a predetermined number of cycles. and the battery voltage variation period monitoring means for stopping the command for the battery voltage applied to the starter driving command means as migrated, the server
Select whether to enable or disable the operation of the battery voltage fluctuation cycle monitoring means
And a selection switch for performing the selection .

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing the overall configuration of an engine start control device according to the present invention. In the figure, an engine start control device 1 of the present invention includes a start command signal output means for outputting a start command signal s to an engine, and a start-related device command for instructing a start-related device 11 to perform a predetermined operation based on the start command signal s. Means 3, a starter drive commanding means 4 for commanding and driving the application of the battery voltage V to the starter 8 based on the start command signal s, and monitoring the fluctuation period ΔT of the battery voltage V and monitoring the fluctuation period ΔT of the battery voltage V. When it is detected that is continuously shortened over a predetermined number of cycles, it is determined that a transition has been made from cranking to engine start. Battery voltage fluctuation cycle monitoring means 5 for stopping application of battery voltage V to starter drive command means 4 And

The above-mentioned start command signal output means is, for example, the time setting device 2 of the operation unit 23 arranged at the front of the driver's seat.
31 and a timer 7 that operates according to the setting. The start command signal s in this configuration is used when the time or time set by the driver with the time setting device 231 elapses.
Output from The set time and set time in the time setting unit 231 are displayed on the display unit 13 so that the driver can easily set the time while watching the display. The start command signal output means includes, for example, a remote controller (remote controller) 22 and a radio wave detection circuit 21. In this configuration, the start command signal s outputs a radio wave emitted from the remote control 22 when the driver operates indoors. The signal is received by the radio wave detection circuit 21 by the antenna 21a, and is output from the radio wave detection circuit 21 in response thereto.

The above-mentioned start-related equipment command means 3, starter drive command means 4, and battery voltage fluctuation cycle monitoring means 5
Constitute the engine start control unit 10. The engine start control unit 10 is a microcomputer that operates around a CPU.
Are respectively configured as functions of software executed by the CPU according to a predetermined control program stored in the ROM. In addition, the above timer 7 and A
The / D converter 6 is also built in the microcomputer,
Signals are exchanged with the CPU via a bus.

When the start-related device command means 3 receives the above-mentioned start command signal s, it causes the start-related device 11 to perform a predetermined operation. For example, in the case of a gasoline-powered vehicle, a command signal is output to the ignition coil to generate a high voltage based on the battery voltage V and supply the high voltage to the ignition plug, thereby causing spark discharge in the cylinder.

When the starter drive command means 4 receives the start command signal s, it sends out a switch-on signal to the starter switch mechanism 14 to bring the starter switch mechanism 14 into a contact state, and applies the battery voltage V to the starter 8. Starter (motor drive circuit and the starter motor) 8 drives the motor by the battery voltage V, whereby the ring gear rotates the crankshaft 12 via a flywheel (not shown), performs cranking.

The battery voltage fluctuation period monitoring means 5 digitizes and takes in the battery voltage V fluctuating with the cranking by the A / D converter 6 and obtains an average when a plurality of conversion data are taken in. V is a recognized value. That is, every time the averaging operation is performed, the battery voltage V
Is updated (hereinafter referred to as “battery recognition value”), and a fluctuation period ΔT of the battery voltage V described below is obtained using the battery recognition value, and the fluctuation period ΔT
The engine start is determined on the basis of.

FIG. 2 is a diagram showing a fluctuation state of the battery voltage. When the starter 8 starts cranking, as shown in the figure, the battery voltage V drops greatly due to the influence of the motor drive by the starter 8 (point A). Thereafter, the battery voltage V rises, and in response to the rise, the battery voltage fluctuation cycle monitoring means 5 detects an increase in the battery recognition value.

Even if cranking continues, if the engine does not start, the battery voltage V drops again (point B) due to the drive of the motor of the starter 8, and the battery recognition value in the battery voltage fluctuation period monitoring means 5 is also reduced. Then, the battery voltage V starts to increase again (point C), and the battery recognition value increases accordingly. At this time, assuming that the battery voltage V has newly increased, the battery voltage variation cycle monitoring means 5 determines the time from the previous time when the battery voltage V newly increased to the time when the battery voltage V newly increases, that is, the variation cycle of the current cycle. Determine ΔT.

As described above, when the starter 8 continues to drive the motor, the battery recognition value by the battery voltage fluctuation period monitoring means 5 repeatedly rises and falls, and every time a new increase in the battery voltage V is detected, the fluctuation period ΔT Is calculated and compared with the fluctuation cycle ΔT of the previous cycle. As a result of the comparison, when it is detected that the fluctuation period ΔT has been shortened continuously over a predetermined number of periods, for example, in FIG. 2, the fluctuation periods ΔT1, ΔT2, ΔT in four consecutive cycles from point D
3. If it is recognized that ΔT4 has the relationship of ΔT1>ΔT2>ΔT3> ΔT4, it is determined that the engine has started.
When it is determined that the engine has started, the power supply from the battery 9 to the starter 8 is cut off, and the cranking is stopped (point E). That is, the application of the battery voltage V to the starter drive instruction means 4 is stopped, and the starter switch mechanism 14 is turned off to stop the motor drive.

FIG. 3 is a flowchart showing the procedure of engine start control according to the present invention. First, in step S1, it is determined whether or not the start command signal s has been input. If it has been input, the process proceeds to the next step S2, otherwise returns directly.

In step S2, a command is issued to the starter 8 and the starting-related equipment 11, and the process proceeds to the next step S3.

In step S3, it is determined whether or not the received battery recognition value has been updated. If the value has been updated, the process proceeds to the next step S4, and if not, the process returns.

In step S4, the current update value is compared with the previous update value to determine whether the current update value is equal to or greater than the previous update value. The process proceeds to the next step S5 assuming that the value is increasing, and returns if it is not equal to or greater than the previous update value.

In step S5, it is determined whether or not the current battery recognition value is a new rise. If it is a new rise, the process proceeds to the next step S6, and if not, the process returns.

In step S6, the time from when the battery recognition value newly increased last time to when the battery recognition value newly increases this time,
That is, the fluctuation cycle ΔT of the current cycle is calculated, and the process proceeds to the next step S7.

In step S7, it is determined whether or not the fluctuation cycle ΔT of the current cycle has been shortened with respect to the previous cycle. If the cycle has been shortened, the process proceeds to the next step S8, and if not, the process proceeds to step S11. Branch.

In step S11, since the fluctuation period ΔT is not shortened, the count number of the continuous shortening cycle is initialized, and the routine returns.

In step S8, it is determined whether or not the fluctuation cycle ΔT has been reduced continuously for a predetermined number of cycles, and if it has been continuously reduced for a predetermined number of cycles, the process proceeds to the next step S9; To return.

In step S9, since the fluctuation period ΔT has been shortened continuously by the predetermined number of cycles, it is recognized that the engine has started, and the routine proceeds to the next step S10.

In step S10, cranking is stopped,
That is, the power supply to the starter 8 is stopped, and the process returns.

As described above, in this embodiment, the battery voltage V is monitored, and the fluctuation period Δ
T is determined, and it is determined that the engine has been started when it is recognized that the fluctuation period ΔT has been continuously reduced by a predetermined number of cycles. Therefore, it is determined from the time of the actual engine start (point F in FIG. 2). Can stop cranking almost at the same time with a slight time lag, minimizing unnecessary cranking after starting the engine, and almost the same cranking as when the driver started the engine by manually operating the ignition switch. Ranking time can be. Therefore, as compared with the conventional method of detecting and recognizing a difference in battery voltage (a method of detecting a rising difference after a certain cranking time (point G in FIG. 2)), cranking is performed faster and more timely. Can be stopped, and wasteful consumption of battery power can be suppressed accordingly.

Further, no special wiring is required for engine start recognition, and therefore, the start of the engine can be more easily recognized.

In the above description, the engine start control according to the present invention is configured to always function. However, the operation unit 23 is provided with a selection switch 232, which is connected to the engine start control unit 10, and the setting by the selection switch 232 is performed. Thus, it may be possible to select whether to operate the engine start control of the present invention or to operate the conventional start control. In this case, the setting of the selection switch 232 is displayed on the display unit 13.

In a situation on the vehicle side such as a battery or the surrounding environment mainly based on the outside air temperature, for example, in an environment of an extremely cold region,
Although the engine start is likely to be unstable, in this embodiment, since the selection switch 232 is provided, in such an extreme situation, the conventional engine start control is selected and the cranking time is extended. In addition, it is possible to stabilize the start, and therefore, it is possible to perform the engine start control according to the situation, and it is possible to more reliably prevent the malfunction of the engine start recognition.

The engine start control device of the present invention can be widely applied to gasoline engines, diesel engines, and other types of engines that are started by a starter, regardless of the type of engine.

[0035]

As described above, according to the engine start control device of the present invention, the battery voltage is monitored and the fluctuation period of the battery voltage is obtained, and the fluctuation period is continuously reduced by a predetermined number. The engine is judged to have started when it detects the engine, so cranking can be stopped almost at the same time with a slight time difference from the actual engine start, minimizing unnecessary cranking after engine start. The cranking time can be made substantially the same as when the driver starts the engine by manually operating the ignition switch. Therefore, compared to the conventional method of detecting and recognizing the difference between the battery voltages,
The cranking can be stopped faster and more timely, and wasteful consumption of battery power can be suppressed accordingly.

Also, no special wiring is required for engine start recognition, and therefore, the start of the engine can be more easily recognized.

Further, since the operation of the battery voltage fluctuation period monitoring means can be selectively permitted or prohibited, it is possible to appropriately cope with the diversification of vehicles and the influence of the environment mainly on the outside air temperature. This can reliably prevent the malfunction of the engine start recognition that occurs.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an overall configuration of an engine start control device of the present invention.

FIG. 2 is a diagram showing a fluctuation state of a battery voltage.

FIG. 3 is a flowchart showing a procedure of engine start control according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 engine start control device 3 start-related equipment command means 4 starter drive command means 5 battery voltage fluctuation period monitoring means 6 A / D converter 7 timer 8 starter 9 battery 10 engine start control unit 11 start-related equipment 12 crankshaft 13 display unit 14 Starter switch mechanism 21 Radio wave detection circuit 22 Remote control 23 Operation section 231 Time setting device 232 Selection switch

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-215052 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F02N 11/08

Claims (1)

(57) [Claims] 1. An engine start control device for automatically starting an engine and performing an idling operation, comprising: a start command signal output means for outputting a start command signal to the engine; and a start-related device based on the start command signal. Start-related device command means for commanding a predetermined operation; starter drive command means for commanding and driving the application of a battery voltage to a starter based on the start command signal; and monitoring the fluctuation period of the battery voltage and monitoring the fluctuation of the battery voltage. Battery voltage fluctuation period monitoring means for stopping the command of the application of the battery voltage to the starter drive command means as transitioning from cranking to engine start when detecting that the cycle has been continuously shortened over a predetermined number of cycles; Permission / prohibition of the operation of the battery voltage fluctuation period monitoring means
And a selection switch for selecting the engine start control.