JPH11229944A - Engine starting controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To start the engine in a short time by carrying out fuel injection control, ignition control and the like in an early stage in a start-up of an engine. SOLUTION: Position signals outputted from a crank angle sensor are turned into angle signals per 5 deg., and as to cylinder detection signals outputted from a cylinder determination sensor, an interval between respective pulses is set to 15 deg. so that a trailing edge position of a head pulse PS is positioned in front of an upper dead point by 30 deg.. In an engine starting time, an angle γrequired for determination of a head pulse PS of the cylinder detection signal is reduced to 30 deg., and within a range of the angle γ, a pulse detected at first from no cylinder detection signal pulse output condition is recognized as the head pulse PS of the cylinder detection signal.

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 suitably used for starting, for example, an automobile engine and the like, and more particularly, to a fuel injection control and the like for a multi-cylinder engine which can be performed at an early stage. The present invention relates to an engine start control device.

[0002]

2. Description of the Related Art In general, an automobile engine is composed of a multi-cylinder engine having a plurality of cylinders, in which fuel injection control and subsequent ignition timing control are repeated for each cylinder. When the engine is started, the crankshaft is rotationally driven by a starter formed of an electric motor or the like, and during this time, the engine is started by performing fuel injection control and ignition control for each cylinder.

Therefore, referring to FIGS. 8 and 9, a prior art engine start control device in a prototype stage will be described with reference to FIG.
A description will be given using a cylinder engine as an example.

First, in FIG. 8, the characteristics from the stop to the start of the engine are shown as a relationship among a start signal, an ignition signal, an injection signal, a position signal, and a cylinder detection signal with respect to the crankshaft angle (crank angle). I have. The engine normally stops at a position 90 ° before and after top dead center, and the characteristic line in FIG. 8 indicates that the engine was stopped at a position of 80 ° before top dead center during the previous operation, Is started.

When the engine is started by outputting a start signal to the starter of the engine, for example, the fourth cylinder reaches the top dead center at the position of # 4 and the second cylinder at the next position of # 2. Reached the top dead center, and after that, at # 1, # 3
It is assumed that the cylinder and the third cylinder sequentially reach the top dead center.
Thereafter, the cylinders again reach the top dead center position in order of # 4, # 2, # 1, and # 3 for performing fuel injection control and the like.

The cylinder detection signal is a signal output from a cylinder signal output means such as a rotation sensor provided on the camshaft side of the engine. For example, at the position of # 4, the fourth cylinder reaches the top dead center. This is output as a four-pulse signal to determine this. At the next position # 2, a cylinder detection signal is output as a two-pulse signal in order to determine that the second cylinder has reached the top dead center.
At the position # 3, a cylinder detection signal is output as a signal of one pulse and three pulses, respectively, whereby it can be determined that the first and third cylinders have reached the top dead center.

Here, the cylinder detection signal is set such that the falling position of the leading pulse is always at a position 60 ° before the top dead center, and the interval between each pulse is set to, for example, 30 °.

On the crankshaft side of the engine, there is provided a position signal output means such as a rotation sensor for detecting a rotational position of the engine as a crank angle and outputting a position signal. The position signal is output, for example, as an angle signal for every 10 °. At positions 60 ° before and after the top dead center of each cylinder, a notch of an angle α (for example, about 20 °) is provided in the middle of the position signal. Intervening. This notch absorbs variations between the camshaft-side cylinder detection signal and the crankshaft-side position signal, and detects the first position signal after the head pulse of the cylinder detection signal is output as a reference signal. belongs to.

In the prior art, when performing so-called sequential injection for each cylinder of the engine,
An injection signal is output based on the first position signal after the notch. For example, fuel injection is performed on the first cylinder reaching the top dead center at the position of # 1 by the injection signal. afterwards,
On this cylinder side, an intake stroke and a compression stroke are performed, and an ignition signal is generated at a stage before the end of the compression stroke, that is, at a position preceding the top dead center position of # 4 by the advance angle β calculated in advance. Is output. Then, the engine is started by the ignition signal.

[0010]

In the prior art described above, the position signal on the crankshaft side is output as an angle signal at every 10 °, and the cylinder detection signal is such that the falling position of the leading pulse is 60 degrees before the top dead center. ° position,
Since the interval between each pulse is set to about 30 °,
In order to perform cylinder discrimination based on the number of pulses of the cylinder detection signal, it is necessary to identify a leading pulse located 60 ° before a top dead center (for example, the top dead center position of # 4 shown in FIG. 9). In order to identify the first pulse, it is necessary to confirm that no cylinder detection signal has been output during at least the output of the position signal of 5 pulses (the angle of 50 ° shown in FIG. 9). No.

That is, the pulse interval of the cylinder detection signal is 30 °
During this period, there is a possibility that a position signal corresponding to a maximum of 4 pulses is output. Therefore, from the state where there is no pulse output of the cylinder detection signal for 50 ° of the crank angle (5 pulses of the position signal), Must be detected as the first pulse of the cylinder detection signal, and cylinder discrimination must be performed based on the number of pulses from the first pulse.

However, when the engine is normally stopped, an intermediate portion between the top dead center and the bottom dead center of each cylinder, for example, 90 ° before the top dead center is reached.
It often stops before and after. When the engine is started from the stop position (for example, a position at 80 ° before the top dead center of # 4), the angle (60 ° + 50) required to identify and detect the leading pulse in the cylinder of # 4. Since (°) is not satisfied, the cylinder determination cannot be performed at the position of # 4, and the first cylinder determination is performed at the position of # 2 shown in FIG.

For this reason, in the prior art, when performing so-called sequential injection, after performing the first cylinder discrimination at the position # 2, the injection control is performed in a state where the fuel injection timing is calculated at the next position # 1. It will be done for the first time,
There is an unsolved problem that the fuel injection control at the time of starting the engine is delayed up to the third cylinder (position # 1) after the start of the engine.

Further, when the ignition control is executed thereafter, the intake stroke and the compression stroke are performed in the cylinder in which the fuel injection control is performed, and for example, the ignition of the advanced angle β with respect to the top dead center position of # 4 The timing is calculated and the ignition control is performed. For this reason, the crankshaft of the engine must be continuously driven by the starter for at least two rotations (720 ° of the crank angle) before the first ignition control is performed after the starter starts the engine by the start signal. Not
There is a problem that the actual start time of the engine is delayed.

On the other hand, even in the case of an engine of the type in which simultaneous injection is performed separately from the above-described sequential injection, when the engine is started from the stop position (the position at 80 ° before the top dead center of # 4 illustrated in FIG. 8). Since the first pulse cannot be detected at the position of # 4, which is the first top dead center, the next # 2
The first injection control becomes possible after detecting the leading pulse of the cylinder detection signal at a position 60 ° before the top dead center position of
There is a problem that the subsequent ignition control is also delayed to a position before the top dead center of # 3.

The present invention has been made in view of the above-mentioned problems of the prior art,
The present invention has been made by intensive studies, and the present invention provides an engine start control device capable of performing fuel injection control, ignition control, and the like at an early stage when the engine is started, and enabling the engine to be started in a short time. It is intended to be.

[0017]

In order to solve the above problems, the present invention provides a starter for starting an engine,
Position signal output means for detecting the rotational position of the engine rotationally driven by the starter and outputting a position signal; and cylinder detection comprising different pulses at positions near the top dead center of each cylinder for performing cylinder discrimination of the engine. An engine comprising: cylinder signal output means for outputting a signal; and control means for performing start control for each cylinder of the engine in accordance with a cylinder detection signal from the cylinder signal output means and a position signal from the position signal output means. Applied to the start control device.

The first aspect of the present invention is characterized in that the first pulse angle of the cylinder detection signal with respect to the top dead center of each cylinder and the first pulse at the time of starting the engine are determined. The total angle with the angle
The angle is set to 45 ° or more and 70 ° or less before the top dead center.

According to the above configuration, since the total angle is set to an angle of 45 ° or more and 70 ° or less before the top dead center, for example, the normal stop position (the top dead center and the bottom dead center for each cylinder). When the engine is started by the starter from a position 90 ° before and after the top dead center, which is an intermediate portion between the two, the head pulse of the cylinder detection signal output from the cylinder signal output means can be identified and detected. Can be performed at an early stage, and the start control can be promptly executed for each cylinder.

Further, in the invention according to claim 2, the control means includes:
Injection control means for calculating fuel injection timing for each cylinder in accordance with a cylinder detection signal from the cylinder signal output means and a position signal from the position signal output means, and controlling fuel injection, and a cylinder from the cylinder signal output means An ignition control means for calculating an ignition timing for each of the cylinders according to a detection signal and a position signal from the position signal output means and performing ignition control.

Thus, the injection control means calculates the fuel injection timing for each cylinder in accordance with the cylinder detection signal from the cylinder signal output means and the position signal from the position signal output means, and injects fuel into each cylinder. Control can be performed promptly. Also, the ignition control means can calculate the ignition timing for each cylinder in accordance with the cylinder detection signal and the position signal, and perform the ignition control for each cylinder at an early stage.

Further, according to the third aspect of the present invention, the total angle is set to an angle of 50 ° or more before the top dead center and 60 ° or less. Thus, even when the engine is stopped at a position 90 ° before and after the top dead center during the previous operation, for example, at a position about 80 ° before the top dead center, when the engine is started from this stopped position, the cylinder signal is output. The leading pulse of the cylinder detection signal output from the output means can be detected with a margin of at least about 20 °, the accuracy of cylinder discrimination can be improved, and the start control for each cylinder can be quickly executed.

According to the present invention, the position signal output means is provided on the crankshaft side of the engine, and detects the rotation angle of the crankshaft at regular intervals. It is provided on the camshaft side, and is configured to output a cylinder detection signal having a different number of pulses for each cylinder.

Thus, a position signal can be output from the crankshaft side of the engine, and a cylinder detection signal can be output from the camshaft side.

[0025]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing the configuration of an engine start control apparatus according to an embodiment of the present invention;

FIGS. 1 to 4 show a first embodiment of the present invention. In this embodiment, a case where so-called sequential injection is performed for each cylinder of an engine will be described as an example.

In FIG. 1, reference numeral 1 denotes an engine start switch. The start switch 1 is constituted by an ignition switch provided in a cab (not shown) of the vehicle, and is closed by a driver of the vehicle when the engine is started. You. When the start switch 1 is closed, a start signal is output as shown in FIG. 3, and a starter 2 described later is operated by the start signal.

Reference numeral 2 denotes a starter composed of an electric motor or the like. The starter 2 starts and cranks the engine by rotating a crankshaft (not shown) serving as an output shaft of the engine at the time of starting.

Reference numeral 3 denotes a crank angle sensor as position signal output means disposed near the crankshaft. The crank angle sensor 3 includes, for example, a magnet and a Hall element (both not shown) in a sensor case. It is constituted by a provided rotation sensor.

Here, a rotary plate (not shown) such as a flywheel is provided on the crankshaft, and a plurality of tooth portions are provided around the entire circumference of the rotary plate at intervals of, for example, about 5 °. Is formed. The crank angle sensor 3 detects this as the rotational position of the engine each time each tooth portion approaches or separates from the Hall element with the rotation of the crankshaft, and detects the 5 ° angle as shown in FIGS. 3 and 4. Each position signal is output to a control unit 7 described later.

Further, on the outer peripheral side of the rotary plate, the top dead center of each cylinder corresponding to the leading pulse PS of the cylinder detection signal described later (the positions of # 4, # 2, # 1, # 3 shown in FIG. 3). ) Previous 3
Notches at an angle α1 (for example, about 20 °) are formed in the middle of each tooth portion at positions before and after 0 °. This allows
The position signal from the crank angle sensor 3 is output, for example, as a notch at an angle α1 over a range of 20 ° to 40 ° before the top dead center (position of # 4) as shown in FIG.

The difference between the camshaft-side cylinder detection signal and the crankshaft-side position signal, which will be described later, is absorbed by the notch at the angle α1, and the leading pulse PS of the cylinder detection signal is obtained.
Can be detected as a reference signal for starting control described later.

Reference numeral 4 denotes a cylinder discriminating sensor as cylinder signal output means. The cylinder discriminating sensor 4 is provided on a camshaft (not shown) side of the engine, and is shown in FIGS. 3 and 4 as the camshaft rotates. Such a cylinder output signal is output. This cylinder detection signal is output as a 4-pulse signal in order to determine that the fourth cylinder has reached the top dead center at the position # 4, for example, in the same manner as the cylinder detection signal described in the prior art. Is done. At the next positions # 2, # 1, and # 3, two, one, and three pulses, respectively, are used to determine that the second, first, and third cylinders have reached top dead center. The cylinder detection signal is output as a signal.

However, the cylinder detection signal used in the present embodiment is such that the falling position of the leading pulse PS is always 30 degrees before the top dead center.
°, and the interval between each pulse is set to, for example, 15 °.

Numeral 5 is a fuel injection valve for injecting fuel toward the combustion chamber of the engine, and numeral 6 is an ignition device for igniting the injected fuel. The ignition device 6 is controlled together with the fuel injection valve 5 as shown in FIG. Connected to the output side of unit 7,
The ignition control is performed on a mixture of intake air and injected fuel for each cylinder of the engine, and the mixture is burned (exploded).

Reference numeral 7 denotes a control unit as control means constituted by a microcomputer or the like. The control unit 7 has its input side connected to the start switch 1, the crank angle sensor 3, the cylinder discriminating sensor 4 and the like as shown in FIG. The output side is connected to the starter 2, the fuel injection valve 5, the ignition device 6, and the like.

The control unit 7 is, for example, R
A storage unit 7A including an OM, a RAM, and the like;
A stores the program and the like shown in FIG. The control unit 7 performs an engine start control process and the like according to the program shown in FIG.

The engine start control device according to the present embodiment has the above-described configuration. Next, an engine start control process by the control unit 7 will be described with reference to FIGS.

First, when the processing operation is started, it is determined in step 1 whether or not the start switch 1 is turned on and a start signal is output. If "YES" is determined, the process proceeds to step 2 where the drive signal is transmitted to the starter 2. And the engine is started (cranking) by operating the starter 2.

In the next step 3, the position signal output from the crank angle sensor 3 is read, and the cylinder detection signal is read from the cylinder discrimination sensor 4.
Then, in step 4, it is determined whether or not the leading pulse PS of the cylinder detection signal has been output (detected) based on the position signal and the cylinder detection signal, and the process returns to step 3 while determining "NO". The reading of each signal is continued.

Next, when "YES" is determined in step 4, the cylinder output from the cylinder discriminating sensor 4 at a position 30 ° before the top dead center position of # 4 shown in FIGS. Since the first pulse PS of the detection signal is detected, the process proceeds to step 5 to sequentially read the cylinder detection signal pulses following the first pulse PS, and performs cylinder discrimination control according to the number of pulses of the cylinder detection signal.

In this case, it is the fourth cylinder that first reaches the top dead center at the position # 4, and the cylinder detection signal is output as a four-pulse signal. Can be determined to have reached the top dead center, and the second to reach the top dead center at the position of ♯2 is the second
It can be determined that the cylinder is the cylinder.

Next, at step 6, when the rotational position of the engine is notched by an angle α1 at a position on the front side of the position of # 2 illustrated in FIG. (Corresponding to the position of the leading pulse PS output at the position), the fuel injection timing in the second cylinder is determined based on whether or not the first position signal after the notch is output, and the determination is "YES". The determination processing of step 6 is continued until the determination is made. And
If "YES" is determined in step 6, the process proceeds to the next step 7, in which a fuel injection signal is output to the fuel injection valve 5 at a position that is a predetermined angle before the position of # 2 shown in FIG.
The fuel injection control by so-called sequential injection is executed.

Next, at step 8, it is determined whether or not the cylinder (for example, the second cylinder) for which the fuel injection control has been performed has reached the ignition timing. When the determination is "YES", the routine proceeds to step 9. Then, a control signal is output to the ignition device 6 to execute ignition control for the air-fuel mixture in the ignition cylinder, and the process returns in step 10.

That is, on the cylinder side where the fuel injection control is performed, the suction stroke is performed from the position # 2 to the position # 1 and the position of the next # 1 to the position # 3 (see FIG. 3). In the compression stroke up to, the advance angle β calculated in advance
The ignition control is performed at the position (1), and at this time, the engine is started by burning (exploding) the air-fuel mixture in the cylinder.

Thus, according to the present embodiment, the position signal output from the crank angle sensor 3 on the crankshaft side is an angle signal for every 5 °, and the cylinder detection signal output from the cylinder discrimination sensor 4 is The interval between each pulse is set to 1 so that the falling position of the pulse PS is 30 ° before the top dead center.
Since the angle is set to 5 °, the angle γ (hereinafter referred to as a required angle γ) required to determine the leading pulse PS of the cylinder detection signal at the time of starting the engine is γ = 30 as shown in FIG. °, and the following operational effects can be obtained.

That is, the pulse interval of the cylinder detection signal is 15 °
During this time, there is a possibility that a position signal (a signal every 5 °) for a maximum of four pulses is output. For this reason, it is possible to detect the first pulse of the cylinder detection signal output as the first pulse PS from a state where no pulse of the cylinder detection signal is output for at least five pulses (25 ° of the crank angle) of the position signal. it can.

However, at the position 30 ° before and after the top dead center at which the leading pulse PS of the cylinder detection signal is output, a notch with an angle α1 is formed in the position signal, so that the cylinder is not opened when the engine is started. The required angle γ for determining the leading pulse PS of the detection signal is an angle corresponding to 30 ° of the crank angle, and is output first when there is no pulse output of the cylinder detection signal in the range of this angle γ. The pulse can be identified as the leading pulse PS of the cylinder detection signal.

Therefore, in this embodiment, the leading pulse PS of the cylinder detection signal is set at a position 30 ° before the top dead center, and the leading pulse Ps of the cylinder detection signal is set when the engine is started.
The required angle γ for determining S is 30 °, and the total angle θ of the angle of the leading pulse PS and the required angle γ is

[0050]

## EQU1 ## θ = (γ + 30 °) = 60 °.

When the engine stops at a position 90 ° before and after the top dead center during the previous driving of the vehicle, for example, at a front position of about 80 ° from the top dead center position of # 4 shown in FIG.
When starting the engine from this stop position, $ 4
The position signal from the crank angle sensor 3 can be continuously output from a front position of about 80 ° from the top dead center position, and the angle at this time is represented by a total angle θ (θ = 60) shown in FIG.
°) can be ensured as a sufficiently large angle.

As a result, after starting the engine from the stop position, it is confirmed that no cylinder detection signal is output at least in the range of the required angle γ (30 °), and then the first cylinder output is output. The pulse of the detection signal can be reliably identified as the leading pulse PS, and the cylinder of the engine can be determined early according to the number of pulses of the cylinder detection signal following the leading pulse PS.

Therefore, according to the present embodiment, it is possible to perform the cylinder discrimination in the cylinder which first reaches the top dead center when the engine is started, for example, the cylinder indicated by # 4 in FIG. On the other hand, the sequential injection of fuel can be quickly and stably executed, and by subsequently performing the ignition control on the air-fuel mixture, the time required for the engine start control can be reliably reduced.

Thus, fuel injection control, ignition control, and the like can be executed at an early stage when the engine is started, and the engine can be started in a short time. Then, for example, idle stop control (control for automatically stopping the engine every time the engine speed is reduced to the idling state)
Even in a vehicle adopting the above-described method, the engine can be started early according to the depression operation of the accelerator pedal, and the fuel efficiency and the like of the engine can be reliably improved.

Next, FIG. 5 shows a second embodiment of the present invention. In this embodiment, the same reference numerals are given to the same components as those in the first embodiment, and the description thereof will be omitted. It shall be. However, a feature of the present embodiment is that the position signal output from the crank angle sensor 3 on the crankshaft side is an angle signal every 5 °, and the cylinder detection signal output from the cylinder discrimination sensor 4 is Falling position 2 before top dead center
The configuration is such that the interval between each pulse is set to 10 ° so as to be at a position of 0 °.

Here, the pulse interval of the cylinder detection signal is 10
°, and during this time the position signal (5 °
For each signal) may be output. For this reason, it is possible to detect the first pulse of the cylinder detection signal output as the first pulse PS from a state in which no pulse of the cylinder detection signal is output for at least four pulses (20 ° of the crank angle) of the position signal. it can.

However, at positions 20 ° before and after the top dead center at which the head pulse PS of the cylinder detection signal is output, a notch having an angle α1 is formed in the position signal. Therefore, the required angle γ for determining the leading pulse PS of the cylinder detection signal at the start of the engine is an angle corresponding to 25 ° of the crank angle, and there is no pulse output of the cylinder detection signal over this angle range. From the state, the pulse output first can be identified as the leading pulse PS of the cylinder detection signal.

Therefore, in this embodiment, the first pulse PS of the cylinder detection signal is set at a position 20 ° before the top dead center, and the first pulse Ps of the cylinder detection signal is set when the engine is started.
The required angle γ for determining S is 25 °, or 30 ° with a margin for one pulse of the position signal, and the total angle θ of the angle of the leading pulse PS and the required angle γ is 45 ° or 50 °. It is what you have set.

Thus, in the present embodiment configured as described above, substantially the same operation and effect as those of the first embodiment can be obtained. In particular, in the present embodiment, the angle of the leading pulse PS and the angle of the first pulse PS are different. The total angle θ with the required angle γ is 45 °
Alternatively, since the engine is set at 50 °, the cylinder temporarily reaches the top dead center even if the engine is temporarily stopped at a position 60 ° before and after the top dead center during the previous operation and the engine is started from this position. For example, in the cylinder indicated by # 4 in FIG. 5, cylinder discrimination can be quickly performed, and the time required for engine start control can be reliably reduced.

Next, FIG. 6 shows a third embodiment of the present invention. In this embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. It shall be. However, a feature of the present embodiment is that the position signal output from the crank angle sensor 3 on the crankshaft side is an angle signal every 5 °, and the cylinder detection signal output from the cylinder discrimination sensor 4 is Falling position 3 before top dead center
The interval between each pulse is set to 17.5 so as to be at a position of 5 °.
°.

Here, the pulse interval of the cylinder detection signal is 1
7.5 °, during which time there is a possibility that position signals (signals every 5 °) for up to four pulses are output. For this reason, at least 5 pulses of the position signal (25 crank angles)
(°) The pulse of the cylinder detection signal output first can be detected as the leading pulse PS from the state where there is no pulse output of the cylinder detection signal for minutes.

However, at the position 35 ° before and after the top dead center at which the head pulse PS of the cylinder detection signal is output, a notch having an angle α1 is formed in the position signal. For this reason, the required angle γ for determining the leading pulse PS of the cylinder detection signal at the time of starting the engine is an angle corresponding to 30 ° of the crank angle, and there is no pulse output of the cylinder detection signal over this angle range. From the state, the pulse output first can be identified as the leading pulse PS of the cylinder detection signal.

Therefore, in this embodiment, the first pulse PS of the cylinder detection signal is set at a position 35 ° before the top dead center, and the first pulse Ps of the cylinder detection signal is set when the engine is started.
The required angle γ for determining S is 30 ° or 35 ° with a margin, and the total angle θ of the angle of the leading pulse PS and the required angle γ is set to 65 ° or 70 °. .

Thus, in the present embodiment configured as described above, substantially the same operation and effect as those of the first embodiment can be obtained. In particular, in the present embodiment, the angle of the leading pulse PS and the angle The total angle θ with the required angle γ is 65 °
Or, since the engine is set at 70 °, the cylinder stops at the position 80 ° before and after the top dead center during the previous operation and starts the engine from this position. For example, the cylinder discrimination can be quickly performed in the cylinder indicated by # 4 in FIG. 6, and the time required for the engine start control can be reliably reduced.

In the third embodiment, the first pulse P of the cylinder detection signal output from the cylinder discrimination sensor 4 is used.
S so that the falling position is 35 ° before top dead center,
Although it has been described that the interval between each pulse is set to 17.5 °, in place of this, for example, the leading pulse PS of the cylinder detection signal is set so that the falling position becomes the position 36 ° before the top dead center. The interval between each pulse may be set to 18 °, and even in this case, the total angle θ can be set to 70 ° or less before the top dead center.

Next, FIG. 7 shows a fourth embodiment of the present invention. In this embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. It shall be. However, a feature of the present embodiment is that fuel injection control is performed as so-called “simultaneous injection” for each cylinder of a four-cylinder engine based on the output timing of the reference signal.

That is, even when the engine is stopped at a position 90 ° before and after the top dead center at the time of the previous driving of the vehicle, for example, about 80 ° from the top dead center position of # 4 shown in FIG. When starting the engine from this stop position,
The first pulse PS of the cylinder detection signal can be detected at a position in front of the position 4 by an angle of about 30 ° as in the case of the first embodiment, and the cylinder detection signal following the first pulse PS can be detected. According to the number of pulses, the cylinder of the engine can be determined early.

Further, when the rotational position of the engine is notched by an angle α1 at a position in front of the position of # 4 illustrated in FIG. 7 (output at a position 30 ° before the top dead center position of # 4). (Corresponding to the position of the leading pulse PS).
The fuel injection timing can be determined using the first position signal after the notch as a reference signal, and a fuel injection signal is output to the fuel injection valve 5 at a position that is a predetermined angle before the position of # 4, so-called "simultaneous injection". ) Can be executed.

The position signal (reference signal) output first after the notch of the angle α1 is the top dead center position (for example, # 4
Position) is output at a position that is a fixed angle earlier than the position), so that when performing fuel injection control by simultaneous injection for each cylinder of the engine, the position as a reference signal output first after the engine is started The fuel injection timing can be promptly determined according to the signal, and by outputting the fuel injection signal to the fuel injection valve 5, fuel injection control by simultaneous injection can be immediately executed for each cylinder of the engine.

Further, thereafter, an intake stroke is performed for each cylinder side of the engine from the position of # 4 to the position of # 2, and in the next compression stroke from the position of # 2 to the position of # 1, calculation is performed in advance. The ignition control can be executed quickly at the position of the advance angle β determined by the above, and at this time, the engine can be started early by burning (exploding) the air-fuel mixture in the cylinder.

Thus, in the present embodiment configured as described above, substantially the same operation and effect as those of the first embodiment can be obtained. In the present embodiment, particularly, in the present embodiment, the start-up of the engine by the starter 2 is performed. Since the injection control for the fuel by simultaneous injection is performed for each cylinder in accordance with the position signal (reference signal) after the first notch, the third cylinder after the engine is started (# 1 top deadline illustrated in FIG. 7) The ignition control can be performed at the position ahead of the point position by the advance angle β), and the engine start timing can be reliably advanced.

In each of the above embodiments, in the program shown in FIG. 2, steps 6 and 7 show specific examples of the injection control means, and steps 8 and 9 show specific examples of the ignition control means. I have.

In each of the above embodiments, the case where the position signal is an angle signal every 5 ° has been described as an example.
The present invention is not limited to this. For example, the pulse interval of the position signal may be an angle signal every 3 ° or 6 °,
In some cases, the angle between the teeth formed on a rotating plate such as a flywheel may be changed as appropriate so that an angle signal is obtained every 8 °.

When the pulse interval of the position signal is changed in this manner, the pulse interval of the cylinder detection signal may be appropriately changed in accordance with the change, and the point is that the cylinder detection signal with respect to the top dead center of each cylinder is changed. The total angle θ of the leading pulse angle and the required angle γ falls within an angle range of 45 ° or more before TDC and 70 ° or less, preferably 50 ° or more before TDC and 60 ° or less. Thus, the pulse interval between the position signal and the cylinder detection signal may be set, respectively.

Further, in each of the above embodiments, a four-cylinder engine has been described as an example. However, the present invention is not limited to this, and may be applied to, for example, a six-cylinder engine or an eight-cylinder engine. .

In the above-described embodiment, the crank angle sensor 3 and the cylinder discriminating sensor 4 are described as being constituted by a rotation sensor including a Hall element, but the present invention is not limited to this. A crank angle sensor and a cylinder detection sensor may be constituted by a rotation sensor of a type.

[0077]

As described above in detail, according to the first aspect of the present invention, the first pulse angle of the cylinder detection signal with respect to the top dead center of each cylinder and the first pulse at the start of the engine are determined. Since the total angle with the required angle is set to an angle of 45 ° or more before the top dead center and 70 ° or less, for example, when starting the engine with a starter from a normal stop position, the total angle The first pulse of the cylinder detection signal output first from the cylinder signal output means at the required angle stage included in the above can be clearly identified and detected, and the cylinder determination of the engine can be performed early. Therefore, the fuel injection control, the ignition control, and the like can be executed early when the engine is started, and the engine can be started in a short time. For example, even in a vehicle that employs idle stop control or the like, the engine can be started early according to the depression operation of the accelerator pedal, and the fuel efficiency and the like of the engine can be reliably improved.

According to the second aspect of the present invention, since the control means comprises the fuel injection control means and the ignition control means for performing the ignition control, the cylinder detection signal and the position signal output means from the cylinder signal output means are provided. The fuel injection timing is calculated for each cylinder by the injection control means according to the position signal from
Fuel injection control can be quickly performed on each cylinder. Then, the ignition control means also calculates the ignition timing for each cylinder according to the cylinder detection signal and the position signal,
The ignition control can be performed on each cylinder at an early stage.

Further, according to the third aspect of the present invention, the total angle of the leading pulse angle and the required angle is set to an angle of 50 ° or more and 60 ° or less before the top dead center. The engine is 90 ° before and after top dead center,
For example, even if you stop at about 80 ° before top dead center,
When the engine is started from this stop position, the leading pulse of the cylinder detection signal output from the cylinder signal output means can be detected with a margin of at least about 20 °, so that the accuracy of cylinder discrimination can be improved and start control for each cylinder can be performed. Can be executed promptly.

Further, according to the present invention, the position signal output means is provided on the crankshaft side of the engine, and the rotation angle of the crankshaft is detected at every fixed angle, and the cylinder signal output means is connected to the camshaft of the engine. Side, and a cylinder detection signal having a different number of pulses for each cylinder is output, so that the first pulse for cylinder discrimination can be stably detected according to the position signal and the cylinder detection signal, and the cylinder discrimination can be performed early. It is possible to stabilize the start control of the engine and improve the reliability.

[Brief description of the drawings]

FIG. 1 is a control block diagram showing an engine start control device according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing an engine start control process by a control unit.

FIG. 3 is a characteristic diagram illustrating a relationship among a crankshaft angle, a start signal, an ignition signal, an injection signal, a position signal, and a cylinder detection signal according to the first embodiment.

FIG. 4 is a characteristic diagram showing a position signal and a cylinder detection signal in FIG. 3 in a partially enlarged manner.

FIG. 5 is a characteristic diagram of a position signal and a cylinder detection signal showing an engine start control device according to a second embodiment.

FIG. 6 is a characteristic diagram of a position signal and a cylinder detection signal showing an engine start control device according to a third embodiment.

FIG. 7 is a characteristic diagram of a start signal, an ignition signal, an injection signal, a position signal, and a cylinder detection signal, which shows an engine start control device according to a fourth embodiment.

FIG. 8 shows the crankshaft angle and the starting signal according to the prior art;
FIG. 3 is a characteristic diagram showing a relationship among an ignition signal, an injection signal, a position signal, and a cylinder detection signal.

FIG. 9 is a characteristic diagram showing a position signal and a cylinder detection signal in FIG. 8 in a partially enlarged manner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Start switch 2 Starter 3 Crank angle sensor (position signal output means) 4 Cylinder discrimination sensor (cylinder signal output means) 5 Fuel injection valve 6 Ignition device 7 Control unit (control means) # 1-# 4 Top dead center position PS top Pulse γ Required angle θ Total angle

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification code FI F02N 11/08 F02N 11/08 Y 17/08 17/08 Z F02P 5/15 F02P 5/15 E

Claims (4)

[Claims] 1. A starter for starting an engine, a position signal output means for detecting a rotational position of an engine rotationally driven by the starter and outputting a position signal, and a signal for each cylinder for discriminating a cylinder of the engine. Cylinder signal output means for outputting a cylinder detection signal composed of pulses different from each other at a position near the top dead center, and the engine according to the cylinder detection signal from the cylinder signal output means and the position signal from the position signal output means. An engine start control device, comprising: a control unit that performs start control for each cylinder, wherein a start pulse angle of the cylinder detection signal with respect to a top dead center of each of the cylinders and the start pulse are determined when the engine is started. A total angle of 45 ° or more before the top dead center and 70 ° or less. Down of the start control device. 2. The control means calculates a fuel injection timing for each cylinder in accordance with a cylinder detection signal from the cylinder signal output means and a position signal from the position signal output means, and controls fuel injection. Injection control means for performing ignition control for performing ignition control for each cylinder in accordance with a cylinder detection signal from the cylinder signal output means and a position signal from the position signal output means. The engine start control device according to claim 1, comprising: 3. The total angle is 50 ° or more before top dead center,
The engine start control device according to claim 1 or 2, wherein the angle is set to 60 ° or less. 4. The engine according to claim 1, wherein said position signal output means is provided on a crankshaft side of said engine, and detects a rotation angle of said crankshaft at every predetermined angle. 4. The engine start control device according to claim 1, wherein each of the plurality of cylinders is configured to output a cylinder detection signal having a different pulse number for each of the cylinders. 5.