JPH0427726A - Automotive diesel engine control device - Google Patents

Abstract

PURPOSE:To avoid generation of any abnormal sound in a differential gear and transmission of any unpleasant driving noise into the cabin of a vehicle by judging low speed running with the high speed gear of the vehicle, and making control to increase the amount of fuel injection so as to increase the revolutions of an engine. CONSTITUTION:An operating condition exceeding a set value lower than idle rotational speed in a running condition with the gear set in a high speed position is judged by a judging means 4. The amount of fuel injection is increased by way of a first idling control device 1 during a low speed running with high speed gear of a vehicle, based on the result of the judgment to increase an engine speed and make the fluctuation rate of the engine speed reduce. Thereby, even when running at a low speed in a high speed gear position being liable to generate abnormal sound from a differential gear, the engine speed fluctuation of an input side gear of the differential gear is sufficiently restricted and collision of mating gear surfaces between input side gears and output side gears.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a control device for an automobile diesel engine.

(Prior art and its problems) [fl'jih F! The M7” easel engine is equipped with a fast idle control device that increases the fuel injection amount in response to an increase in load during idle operation, such as when the air conditioner air conditioner air conditioner used for air conditioning in a single room is activated. (Refer to Publication No. 57-22762).

By the way, diesel engines have relatively large F-lux fluctuations at low engine speeds, so abnormal noises are generated from the day 7 allencial gear that is interposed in the thread path that transmits the torque generated by the engine to the front and rear wheels. It happens.

This noise occurs when driving at low speed in the high gear position where the rotational speed fluctuation of the input side gear of the Day 7T rental gear becomes large, and is caused by repeated collisions between the paper and the output side gear. do. Particularly in four-wheel-drive vehicles, we have had the problem that this collision noise becomes an unpleasant noise that can be heard inside a single room.

The present invention aims to solve these conventional problems.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides an automotive diesel engine equipped with a fast idle control device 1 that adjusts the fuel injection amount during idle operation, as shown in FIG. In the control device, means 2 for detecting the engine speed, means 3 for detecting that the transmission of the vehicle is in the high gear position, and a set value for the engine speed to be lower than the idle speed when the vehicle is in the high gear position. means 4 for determining whether the driving condition has deteriorated by exceeding
A driving means 5 for increasing the fuel injection amount is provided.

(Function) Even during idle operation of a diesel engine with relatively large speed fluctuations, the 7-earth idle control device increases the fuel injection amount and increases the engine rotational speed to keep the engine busy. Mobility rate decreases. This allows low 7+ at the high gear position where abnormal noise is likely to occur from the Day 7 allencial gear! ! Even when driving, the input 1IIs of the Day 7 Allen gear sufficiently suppresses the rotational speed fluctuations of the vehicle and prevents collisions between the tooth surfaces between the outputs JllIll and the unpleasant driving noise, especially in four-wheel drive vehicles. This can prevent overhearing in the room.

(Example) Embodiments of the present invention will be described below with reference to the accompanying drawings.

As shown in FIG. 2, a control lever 1 adjusts the fuel injection amount of a fuel injection pump 11 of a diesel engine.
5 is connected to an actuator (Guiya 7 ram device) 12, and negative pressure from a vacuum pump 13 is applied to this 7 actuator 12 as its driving pressure.
By adjusting the opening time of the solenoid valve 14, the control lever 15 is rotated and the fuel injection amount during idling operation is adjusted.
This 'L//ite/globe 1 and 4, which make up the Earth Idol Co./Troll differential 1, has a valve opening time of 0 to 100% depending on the pulse signal sent from the control unit 10. Duty control is performed between the valve opening time and the control lever 15 is rotated to increase the fuel injection amount as the valve opening time becomes longer.

The control unit 10 includes a CPU, RAM, and ROM.
WI! is a microcomputer consisting of an interface, etc. Various load signals such as the detection signal n11 from the engine circulation sensor 17 [the detection signal V from the continuous sensor 18] and the air conditioner operation signal are inputted via the interface, and the valve 14 is operated according to this information. Appropriately control the duty value of the signal that drives the
Feedback control of idle speed.

In the present invention, a driving state in which the engine speed n decreases by exceeding a set value n1 lower than the idling speed is determined in a driving state in which the engine is in a high gear position, and based on this determination result * low speed driving in both high gears is determined. At times, control is performed to increase the fuel injection amount.

The details of this control will be explained based on the chart 70 shown in FIG.

First, in step 21, the engine speed n and vehicle speed V are read.

In step 22, the gear position of the transmission is calculated based on the series V and the rotational speed n.

In step 23, it is determined whether the transmission is in a high gear position, for example a fourth gear position.

If it is in the four gear position, the process proceeds to step 24, where it is determined whether the rotational speed n is equal to or less than a predetermined value n.

Here, the rotational speed at which abnormal noise occurs in the Day 7 allencial gear is n. (for example, 550 rpm), and if the normal idle speed is ni, the predetermined value n1 is arbitrarily set within the range of ni>01≧110. is set at 〒1.

In this way, if it is determined that the vehicle is running at a low speed where there is a risk that abnormal noise will be generated from the engine rotation (number n is a predetermined value n) or less, the process proceeds to step 25 and a signal is sent to drive the slide/id valve 14. Increase the duty value and turn the control lever 15 by 0 degrees to increase the fuel injection amount.

After increasing the fuel amount, it is confirmed in step 21 that the rotational speed n has increased to a predetermined value n8 or more, and the process proceeds to step 27, where the control to increase the fuel injection amount by the 7-fast idle control device 1 is stopped. Here, the predetermined value n
2 is e1m! by adding a predetermined addition Δn to the predetermined value n1 to prevent hunting from occurring. r) It is set large.

As shown in FIG. 4, the opening degree of the control lever 15 of the pump 11 is changed to the normal idle position when the engine speed decreases beyond a predetermined value. The step is increased by 0 degrees, and the engine speed is increased by Δn. As a result, even when driving at low speed in a high gear position by reducing the engine speed fluctuation rate, the input fIA gear of day 7 allen gear 7 can be Collisions between tooth surfaces can be prevented, and unpleasant driving noise can be prevented from being heard inside the vehicle, especially in four-wheel drive vehicles.

In addition, as another example, a driving state in which the vehicle speed V decreases by exceeding a set value v1 in a driving state in which the vehicle is in the continuous gear position is determined, and based on this determination result * fuel consumption is reduced during low-speed driving in both high gears. It may be configured such that control to increase the injection amount is performed. Here, the predetermined value {circle over (1)} is set to a value lower than the WL speed when the vehicle is running during normal idling operation of the engine, and determines when the vehicle is traveling at a low speed in which there is a risk that abnormal noise may be generated from the vehicle gear 7.

(Effects of the Invention) As described above, according to the present invention, in an automotive diesel engine, by determining when low speed driving is in the high gear of *1illii and controlling to increase the fuel injection amount,
By increasing the number of revolutions of the engine, it is possible to prevent abnormal noise from occurring in the day 7 allencial gear, and to prevent unpleasant driving noise from being heard inside the vehicle especially in a four-wheel drive vehicle.

[Brief explanation of drawings]

Fig. 1 is a diagram corresponding to claims of the present invention, Fig. 12 is a configuration diagram showing actual observation, and Fig. 3 is a diagram showing control contents.
Figure 24 is a diagram showing the action. 1.7 earth idle control device, 2.
...Engine rotation speed detection means, 3.. High speed gear position detection means, 4.. Judgment means, 5.. Driving means. Procedural amendment (voluntary) 1. Indication of the case Patent Application No. 128298 of 1990 2. Name of the invention Automotive diesel engine control device 3. Person making the amendment Relationship to the case Patent applicant address Kana, Yokohama City, Kanagawa Prefecture Yo-ku Takaracho 2 name (
399) Nissan Motor Co., Ltd. 4. Agent 5゜Date of amendment order Voluntary action 7. Contents of amendment (1) From line 4 to line 6 of page 5 of the specification, ``Pulse signal to be sent...Control lever '' should be corrected as follows. “ON-OFF control is performed by the signal sent, and when the solenoid valve 14 opens, the control lever” ” is corrected to ``Determine ON-OFF of the signal.''

Claims (1)

[Claims] A control device for an automotive diesel engine including a fast idle control device that adjusts the fuel injection amount during idling operation, comprising: means for detecting engine rotation speed; and means for detecting that the transmission of the vehicle is in a high gear position; means for determining a driving state in which the engine speed drops beyond a set value lower than the idle speed while the vehicle is in a high gear; and based on the determination result, the first idle control is performed when the vehicle is running at a low speed in a high gear. A control device for a diesel engine for an automobile, comprising a drive means for increasing the amount of fuel injection through a device.