JPH0427739A - Starting controller of engine - Google Patents

Abstract

PURPOSE:To prevent sudden start by providing an ignition timing delay means which delays an ignition timing in response to conditions of water temperature and a throttle valve opening at the starting time of a vehicle. CONSTITUTION:When starting of a vehicle is detected by a detection means A, an ignition timing is delayed by a delay means D in response to conditions of water temperature and a throttle valve opening, and torque is decreased to prevent sudden starting. Since engine stall is apt to happen due to the decrease in the torque, auxiliary air is increased by an increasing means E in response to conditions of the water temperature and the throttle valve opening so as to prevent engine stall, at the same time.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a start control device for preventing sudden start during start while the engine is warming up in a vehicle having an automatic transmission.

<Conventional technology> In conventional vehicle engines, while the engine is warmed up, the engine speed is set at a high idle speed, while the engine's ignition timing, auxiliary air volume, etc. are controlled independently of the vehicle starting operation. Ta.

<Problem to be solved by the invention> However, for some reason, when starting a vehicle with an automatic transmission at a high RPM to warm up the engine, there is a feeling that the engine jumps out.
There was a problem in that it was dangerous, especially when reversing.

In view of these conventional problems, it is an object of the present invention to improve the driving performance at the time of starting.

Means for Solving the Problems> For this reason, as shown in FIG. a throttle valve opening detection means for detecting the water temperature at that time and an ignition timing retardation means for retarding the equinox hole timing according to the water temperature and the throttle valve opening at that time when the vehicle is started; A start control device for a vehicle having an automatic transmission is provided with an auxiliary air increasing means that increases the amount of auxiliary air supplied to the engine by bypassing the throttle valve according to the opening degree of the throttle valve.

<Operation> In the above configuration, when the start of the vehicle is detected, the ignition timing is retarded by an amount corresponding to the water temperature and throttle valve opening at that time, and the torque is reduced to prevent sudden start.

However, since there is a risk of engine stalling due to the decrease in torque, the amount of auxiliary air is increased at the same time according to the water temperature and throttle valve opening to prevent engine stalling.

<Example> An embodiment of the present invention will be described below.

Referring to FIG. 2, the engine 1 includes an air cleaner 2. Intake duct 3. Air is drawn in via the throttle chamber 4 and the intake manifold 5.

The throttle chamber 4 is provided with a throttle valve 6 that interlocks with the accelerator pedal, and an auxiliary air passage 7 that bypasses the throttle valve 6 is provided with an electromagnetic auxiliary air control valve 8.

The intake manifold 5 is provided with an electromagnetic fuel injection valve 9 for each cylinder, which injects fuel into the engine 1 that is pressure-fed by a fuel pump (not shown) and controlled to a predetermined pressure by a pressure regulator.

Each cylinder of the engine 1 is provided with 10 spark plugs,
A high voltage generated by the ignition coil 11 is sequentially applied to these through the distributor 12, thereby igniting a spark to ignite and burn the air-fuel mixture.

Here, auxiliary air control valve 8. The operation of the fuel injection valve 9 and the ignition coil 11 is controlled by signals from a control unit 13 built in a microcomputer, thereby controlling the amount of auxiliary air, the amount of fuel injection, and the ignition timing.

For such control, signals are inputted to the control unit 13 from various sensors.

As the various sensors mentioned above, a hot wire type air flow meter 14 is disposed in the intake duct 3, and the intake air flow rate Q
Check the pressure.

In addition, a crank angle sensor I5 is installed in the distributor 12.
In the case of a 4-cylinder engine, the crank angle is 180°.
outputs a reference signal for each crank angle and a unit signal for each crank angle pi. Here, the engine rotation speed N can be calculated by measuring the cycle of the reference signal or the number of unit signals generated within a predetermined period of time.

Further, a thermistor-type water temperature sensor 16 as water temperature detection means is provided facing the water jacket of the engine 1 to detect the engine cooling water temperature Tw.

Further, a potentiometer-type throttle sensor 17 is attached to the throttle valve 6 as a means for detecting the throttle valve opening degree, and detects the throttle valve opening degree TV○. still,
This throttle sensor 17 also has a built-in idle switch that is set to ○N when the throttle valve 6 is fully closed.

A vehicle speed sensor 18 is also provided to detect vehicle speed VSP.

Also, a position sensor 19 is provided to detect the select lever position of the automatic transmission, and the D range is selected.

Detect R range etc.

Control by the microcomputer in the control unit 13 is performed as follows.

To control the amount of auxiliary air, a basic control value for the valve opening duty ISC is set based on the water temperature Tw detected by the water temperature sensor 16, and this is appropriately corrected to calculate the final valve opening duty 5CON. This is done by giving this duty pulse signal to the auxiliary air control valve 8.

The fuel injection amount is controlled by adjusting the basic fuel injection amount Tp=-Q/from the intake air flow rate Q detected by the air flow meter 14 and the carrot rotation speed N calculated based on the signal from the crank angle sensor 15. Calculate N (K is a constant),
Correct this appropriately to obtain the fuel injection amount "ri='rp-COE"
This is done by calculating F+Ts (COEF is various correction coefficients, Ts is voltage correction) and applying a pulse signal with a corresponding pulse width to the fuel injection valve 9 at a predetermined timing in synchronization with the rotation of the engine 1.

The ignition timing is controlled by setting the basic control value of the ignition timing (ignition advance) ADV based on the engine speed N and the basic fuel injection amount Tp, and correcting this as appropriate to set the final ignition timing A.
This is done by calculating the DV and giving an ignition signal to the ignition coil 11 at a timing based on the DV.

Next, the start control according to the present invention will be explained along the flowchart of FIG.

In step 1 (indicated by Sl in the figure; the same applies hereinafter), it is determined whether or not a start detection flag F is set. If F=0, the process proceeds to step 2.

In step 2, it is determined whether the vehicle speed VSP detected by the vehicle speed sensor 18 is approximately O. If Vsp=o, steps 3 and 4 are executed in preparation for starting.

In step 3, Tw is determined by referring to a map in which the retardation correction amount of the ignition timing at the time of starting the vehicle is stored in advance in accordance with the water temperature Tw and the throttle valve opening TVO.

Search the retard angle correction amount from TVO. Note that, as shown in FIG. 4(a), the retard angle correction amount is set to be larger as the water temperature Tw is lower, and is set larger as the throttle valve opening TVO is smaller.

Step 4 refers to a map in which the amount of supplementary air increase correction amount at the time of starting the vehicle is stored in advance in accordance with the water temperature Tw and the throttle valve opening TVO.

Search the increase correction amount from TVO. Incidentally, as shown in FIG. 4 fb), the increase correction amount here is set to be larger as the water temperature Tw is lower, and as the throttle valve opening TVO is smaller, the increase correction amount is set to be larger.

Next, in step 5, it is determined whether the vehicle is in the D range or the R range based on the signal from the position sensor 19. If the vehicle is in the D range or the R range, the process proceeds to step 6. In step 6, it is determined whether the idle switch has changed from ON to OFF, and if it is OFF, the process proceeds to Step 7. In step 8, a start detection flag F is set.

That is, from the state of vehicle speed vsp=o, the D range or R
When the idle switch changes from ON to OFF (throttle valve is opened) in the range, it is regarded as a start and the start detection flag is set to F=1.

Therefore, step 2. 5. The part 6 corresponds to the start detection means.

After the start detection flag F is set, steps 8 and 9
Execute.

In step 8, the ignition timing is retarded.

That is, the ignition timing ADV is retarded according to the retardation correction amount retrieved in step 3. This part corresponds to the ignition timing retardation means. Note that the retard angle correction amount retrieved in step 3 is used as the initial value of the retard angle correction, and the retard angle correction amount is decreased as time passes. .

In step 9, an increase in the amount of auxiliary air is corrected.

That is, the valve opening duty l for the auxiliary air control valve 8
5Co is increased in accordance with the increase correction amount retrieved in step 4. This part corresponds to the auxiliary air increasing means. Incidentally, the increase correction amount retrieved in step 4 is used as the initial value of increase correction, and the increase correction amount is decreased as time passes.

In step 10, it is determined whether or not a predetermined time has elapsed after the detection of start. If the predetermined time has elapsed, the process proceeds to step 11, where the flag F=O is set, and the correction is ended.

With this kind of control, when starting as shown in Figure 5,
Vehicle speed VSP as shown by the broken line in the diagram when no control is performed
Despite the changes, smooth starting performance as shown by the solid line in the figure can be obtained. .

<Effects of the Invention> As explained above, according to the present invention, when the vehicle starts, the ignition timing is retarded by an amount corresponding to the water temperature and the throttle valve opening to reduce the torque, thereby achieving a sudden start. On the other hand, by increasing the amount of auxiliary air, engine stall can be prevented and starting performance can be improved.

[Brief explanation of drawings]

FIG. 1 is a functional block diagram showing the configuration of the present invention, FIG. 2 is a system diagram showing an embodiment of the invention, FIG. 3 is a flow chart showing control contents, and FIG. 4(a). (b) is a diagram showing a map of the ignition timing retardation correction amount and the auxiliary thrust increase correction amount, and FIG. 5 is a diagram showing the control characteristics. ■...Engine 6...Throttle valve 8...
・Auxiliary air control valve 9...Fuel injection valve 10...
Ignition plug 11...Ignition coil I3...Control unit I6...Water temperature sensor I7...Throttle sensor Patent applicant Japan Electronics Co., Ltd. Representative Patent attorney Hayabusa Fujio Sasashima

Claims (1)

[Claims] In a vehicle having an automatic transmission, a start detecting means for detecting the start of the vehicle, a water temperature detecting means for detecting the engine cooling water temperature, a throttle valve opening detecting means for detecting the throttle valve opening, and The ignition timing retard means retards the ignition timing by an amount corresponding to the water temperature and throttle valve opening at that time, and the engine bypasses the throttle valve by an amount corresponding to the water temperature and throttle valve opening at the time of starting the vehicle. 1. A vehicle start control device comprising: auxiliary air increasing means for increasing the amount of auxiliary air to be supplied.