JPH01121548A - Car engine control device - Google Patents

Abstract

PURPOSE:To prevent a car from uncontrolled running by furnishing a control means to prohibit rise of the engine revolving speed when the acceleration applied to the car has exceeded a set value during backward motion of the car. CONSTITUTION:When a car is starting backward abruptly, an inertia force directed ahead is applied to the driver, which together with pitching phenomenon with the car tail heaved afloat will cause him to stamp the accel. pedal with an excessive force, and so there is a risk of the car being accelerated violently. A pitching sensing means 8 senses this amount of pitching with the aid of a car height sensor 16, and signal is fed into a controller 3. The controller 3 reads the car acceleration G from a shift position sensing means 7 and a pitching amount sensing means 8, and when the reading is greater than the preset value for judgement Go, the fuel injection amount of the injection nozzle 14 is suppressed provisionally. Consequently no engine output will be generated which should cause acceleration of the car, so that it can be prevented from uncontrolled running at the time of backward starting.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an engine control device for a vehicle, and particularly to an engine control device that controls the engine rotational speed during reverse travel.

[Prior art and its problems] Traditionally, as start control for vehicles equipped with automatic transmissions,
Japanese Utility Model Application Publication No. 60-23427 states that when the brake is inactive and the engine speed is higher than a certain set value due to, for example, fast idling or depressing the accelerator pedal, the engine speed changes from neutral (N) to drive range (D). ) has been proposed.

This speed change control device is excellent in that it can effectively prevent a sudden start of the vehicle because the start itself is prohibited, but in reality, there is still room for improvement. In particular, if the driver depresses the accelerator pedal too quickly after switching the shift lever to the reverse position, a so-called pitching phenomenon occurs in which the rear of the car body lifts up, causing forward inertia to act on the driver and causing the driver to depress the accelerator pedal even more. Therefore, countermeasures are desired in this regard.

[Object of the Invention] The present invention was made by focusing on the fact that when a vehicle is suddenly started backwards, a so-called pitching phenomenon occurs in which the front part of the vehicle sinks due to inertia force and the rear part rises up. To provide an engine control device for a vehicle in which the vehicle speed does not increase any further even if the accelerator pedal is further depressed due to pitching.

[Structure of the Invention] Therefore, the present invention includes a shift position detection means for detecting backward movement of the vehicle, an acceleration detection means for detecting acceleration of the vehicle, and a rotation speed control means for controlling the engine speed. An engine control device for a vehicle, characterized in that it is provided with a control means for controlling the engine speed control means so as to prohibit an increase in engine speed when the acceleration acting on the vehicle exceeds a set value when traveling in reverse. It provides:

[Effects of the Invention] According to the present invention, when the vehicle starts backward, even if the vehicle body pitches forward and the accelerator pedal is further depressed, the engine speed is prohibited from increasing. The vehicle will not be accelerated further than this, and sudden acceleration immediately after starting can be reliably prevented.

[Example] Hereinafter, an example of the present invention will be specifically described with reference to the accompanying drawings.

As shown in the system configuration in FIG. 1, a controller 3 consisting of a microcomputer is provided to control an engine 1 and an automatic transmission 2 connected thereto. ．． In addition to the load sensor 5, shift positions (P, R, N) are selected by the shift lever 6.

D, shift position detection means 7 for detecting 2.1);
Pitching amount detection means 8 for detecting the amount of pitching of the vehicle body
(acceleration detection means) and an accelerator position detection means 9 for detecting the amount of depression of an accelerator pedal (not shown).

By the way, the pitching amount detecting means 8, as shown in FIG.
On the other hand, the piston rod cylinder 12 of the damper, whose lower end is connected to the axle 11 of the rear wheel RW, has a structure that allows it to slide, and when the vehicle body is started in reverse from the stopped state shown by the dotted line (A), it changes to the solid line ( When the vehicle body pitches as shown in b), the pitching amount is detected by detecting an increase in the wheel stroke amount of the piston rod cylinder 12 with the vehicle height sensor 16 as shown in the ellipse R. There is.

As the vehicle body pitches, the driver receives a forward inertia force, and as shown in the enlarged circle S, even if the driver intends to depress the accelerator pedal 13 by a amount when starting, the driver actually This is rough due to the influence of pitching.
This may cause the vehicle to suddenly accelerate. As explained below, the present invention takes measures against this problem.

By the way, the above-mentioned controller 3 controls the amount of fuel injected from the fuel injection nozzle 14 that supplies fuel to the engine l based on this information, for example, as shown in the figure, and also controls the hydraulic control circuit ( The control unit controls the operation of the shift solenoids 15-1, 15-2, 15-3 and the lock-up solenoid 16 provided in the vehicle (not shown), thereby achieving a desired vehicle operating state.

Regarding the fuel injection amount and normal control of the automatic transmission, the same control as before is executed, so further explanation will be omitted here, and the countermeasures for the above-mentioned rear start will be explained below.
This will be explained with reference to the flowchart in FIG.

When this control is started, in step #1, the shift position control detected by the shift position detection means 7 and the vehicle acceleration G represented by the pitching amount detected by the pitching amount detection means 8 are read, and in step #2, the vehicle acceleration G is read. , it is determined whether the current shift position is the R (reverse) position. If the vehicle is in the R position, it is detected in step #3 whether the vehicle acceleration G is greater than a predetermined determination value G0, and if so, the process proceeds to step #4 to perform temporary injection control.

If the vehicle is not in the R position, or if the vehicle acceleration G is less than or equal to the determination value 00 even in the R position, normal injection control is performed in step #5. As described above, this normal injection control is the same as the conventional one.

The temporary injection control is performed by setting a fuel injection amount that is sufficiently smaller than the fuel injection amount normally set for the current accelerator position detected by the accelerator position detection means 9. Specifically, the normally set fuel injection amount may be multiplied by an appropriate correction coefficient smaller than "1", and this may be used as the temporary fuel injection amount to be injected by the fuel injection nozzle 14. In this case,
Therefore, since the amount of fuel is reduced, no engine power is generated to accelerate the vehicle, and further acceleration of the vehicle immediately after starting is completely avoided. In addition,
In the above embodiment, when suddenly starting backwards, the increase in engine speed was prevented by controlling the amount of fuel injection, but for example, the opening degree of the throttle valve was controlled electronically. In the case of an engine equipped with an electronically controlled throttle valve, in addition to controlling the fuel injection amount, or instead of this, the engine speed can be controlled by setting the throttle valve opening lower than the throttle valve opening corresponding to the accelerator position. The ignition advance angle may be changed or the ignition advance angle may be changed. In the above embodiment, the vehicle acceleration G is detected by the absolute amount of the wheel stroke amount as the acceleration detection means, but the vehicle acceleration G may be detected by the rate of change of the wheel stroke amount. Further, the G may be detected directly using a G sensor, or further may be detected from the rate of change in vehicle speed.

[Brief explanation of the drawing]

FIG. 1 is a system configuration diagram of a vehicle engine control device according to the present invention, FIG. 2 is an explanatory diagram showing a pitching state of the vehicle, and FIG. 3 is a control program for backward start executed by the controller in FIG. 1. This is the 70-chart. ■...Engine, 2...Automatic transmission, 3...
...Controller, 4...Vehicle speed sensor, 6...
- Shift lever 1 7... Shift position detection means, 8... Pitching amount detection means.

Claims (1)

[Claims] (1) A shift position detection means for detecting the backward movement of the vehicle, an acceleration detection means for detecting the acceleration of the vehicle, and a rotation speed control means for controlling the engine speed, the acceleration acting on the vehicle when the vehicle moves backward. 1. An engine control device for a vehicle, characterized in that a control means is provided for controlling the engine speed control means so as to prohibit an increase in engine speed when the engine speed exceeds a set value.