JPH03233151A - Fuel supply control device for internal combustion engine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a fuel supply control device for an internal combustion engine, and in particular, various detection signals such as the engine speed and cooling water temperature of the internal combustion engine are inputted to a control section, and The present invention relates to a fuel supply control device for an internal combustion engine that controls the amount of fuel supplied by a control unit.

[Prior Art] A fuel supply control device for an internal combustion engine generally controls the air-fuel ratio using an electronic control method.

In other words, engine speed, cooling water temperature, intake pressure, intake air volume,
Various detection signals such as intake air temperature are input to the control unit, and appropriate fuel is supplied to obtain an appropriate air-fuel ratio according to operating conditions.

As a fuel supply control device for an internal combustion engine, Japanese Patent Application Laid-Open No. 83-2
There is one disclosed in Japanese Patent No. 72935. The control device for an internal combustion engine disclosed in this publication introduces a correction amount regarding fuel properties during transient times, and calculates this correction amount when fuel is refueled and when a factor that changes depending on the fuel properties is predetermined. This is done until it falls within the range, optimizing transient drivability and exhaust emissions.

Further, there is one disclosed in Japanese Patent Application Laid-Open No. 1-110850. The fuel supply control device for an engine disclosed in this publication includes a distillation rate detection means for detecting the distillation properties of fuel, which is connected to a steam chamber in a fuel tank, a fresh air introduction passage that sets the steam chamber to atmospheric pressure, and a steam exhaust path. A valve that closes the two passages when detecting the distillation properties, and a temperature sensor and a pressure sensor installed in the steam chamber.
If it is determined that this is the case, a correction is made to increase the injection amount increase value at the time of temporary increase, thereby preventing deterioration of various drivability such as starting performance, acceleration performance, and cold running performance.

[Problems to be Solved by the Invention] By the way, conventional fuel supply control devices for internal combustion engines that do not take into account fuel properties that differ depending on the country or region do not use gasoline, which has a high distillation temperature and is difficult to vaporize. If no control is performed when the fuel is supplied, the air-fuel ratio becomes lean, resulting in disadvantages such as a decrease in idle speed, sluggishness during acceleration in a cold engine, and engine stall during deceleration.

In other words, when using the same fuel as the fuel that determines the set value stored in the control unit, the engine speed Ne after cold start is as shown by the shaded area in FIG. 1(a).
It will be located in area A, which is the target rotation speed range during idling for the water temperature, and when accelerating from start,
As shown by the solid line in Figure (a), the rotation increases and smooth drivability is obtained.

However, if a poor quality fuel that does not match the above-mentioned fuels is used, such as a fuel with a high distillation temperature, the volatility of the fuel will deteriorate, especially when the engine is cold, and the air-fuel ratio will become lean.
As shown in FIG. 1(a), the engine rotational speed Ne after starting the engine becomes lower than the A range.

Furthermore, even when the vehicle is accelerated from a start, the lean air-fuel ratio causes the internal combustion engine to not rev up properly, resulting in a drop in engine speed, as shown by arrow B in Figure 1(a). This causes breathlessness and deteriorates drivability.

Furthermore, when the operating state of the vehicle changes from a running state to a decelerating state and then to an idling state, there is a problem that the engine speed becomes unstable in the idling state after deceleration, and there is a risk of engine stalling. .

Furthermore, even among the methods that take fuel properties into consideration, there is no method that corrects the increase or decrease of fuel based on a detection signal of one of the engine speed, intake negative pressure, and intake air amount when the engine is cold, and the reliability of the control is low. As the resistance decreases, the structure becomes complicated, manufacturing becomes difficult, and the cost becomes large, which is disadvantageous economically.

[Object of the Invention] Therefore, in order to eliminate the above-mentioned disadvantages, the object of the present invention is to measure the engine speed, intake negative pressure, and intake air amount using a detection signal of any one of the engine speed, intake negative pressure, and intake air amount in the engine operating state, which are input when the engine is cold. By providing a control unit that determines the fuel property by comparing the value with a preset and memorized fuel supply setting value, and controls to increase or decrease the fuel supply amount when the fuel property does not match the set value. , determines the fuel properties based on the detected signals of engine speed, intake negative pressure, and intake air amount when the engine is cold, and adjusts the fuel supply amount according to the fuel properties to ensure good driving performance. The object of the present invention is to realize a fuel supply control device for an internal combustion engine that can be used without complicating the structure and with low cost.

[Means for Solving the Problem] In order to achieve this object, the present invention provides a fuel supply control device for an internal combustion engine that has a control section that inputs various detection signals of the internal combustion engine and controls the amount of fuel supplied. The fuel properties are determined by comparing the measured value from the detection signal of either the engine speed, intake negative pressure, or intake air amount input during the engine operating state with the preset and memorized fuel supply setting value. However, the present invention is characterized in that a control section is provided for controlling the amount of fuel supplied to increase or decrease when the fuel properties do not match the set value.

[Function: As described above (Due to the configuration, when the engine is cold, various detection signals of the internal combustion engine are input to the control section, and any one of the engine rotation speed, intake negative pressure, and intake air amount in the engine operating state is detected. The fuel property is determined by comparing the measured value by the signal with the preset and memorized fuel supply setting value, and when the fuel property does not match the set value, the fuel supply amount is controlled to increase or decrease. The amount of fuel supplied is adjusted according to the condition,
In addition to ensuring good operating performance, the structure is not complicated and costs are low.

[Examples] Examples of the present invention will be described in detail below based on the drawings.

1 to 4 show embodiments of this invention. Second
In the figure, 2 is a fuel supply control device, 4 is an internal combustion engine, and 6 is a fuel supply control device.
is the air filter, 8 is the surge tank, 10 is the intake passage,
12 is an exhaust passage.

The fuel supply control device 2 employs, for example, an electronically controlled fuel injection system, and an injector 14 is provided in the intake passage 10, and this injector 14 is connected to a fuel tank 20 via an oil filter 16 and a pressure regulator 18. has been done.

Further, an air flow meter 22 is provided in the intake passage 10 near the downstream side of the air filter 6 to detect the amount of intake air to the internal combustion engine 4 and output a detection signal.

Then, any one of the engine speed, intake negative pressure, and intake air amount in the engine operating state that is input when the engine is cold - for example, a measured value based on a detection signal of the engine speed and a preset value for fuel supply that is stored in advance. A control unit 24 is provided which compares the fuel properties and determines the fuel properties, and when the fuel properties do not match the set value, controls the fuel supply amount to be increased or decreased.

Specifically, the control unit 24 includes the injector 14 that injects fuel, an air flow meter 22 that detects the amount of air taken into the internal combustion engine 4 and outputs a detection signal, and detects the crank angle of a crankshaft (not shown). a crank angle sensor 26 that detects the throttle angle, and a throttle sensor 2 that detects the throttle angle.
8, a power unit 30 which is a battery, an oil pump 32 provided in the fuel tank 20, and an internal combustion engine 4.
A water temperature sensor 34 that detects the water temperature of 0 and an exhaust sensor 0
The two sensors 36 are connected to each other.

As shown in FIG. 3.4, the control unit 24 receives an intake air amount signal which is an air flow signal from the air flow meter 22, an 02 sensor signal which is an oxygen concentration from the 02 sensor 36, engine speed and cooling water temperature. , intake air temperature, throttle signal, vehicle speed signal, etc., and outputs a control signal to increase or decrease the amount of fuel supplied to the injector 14.

Further, as shown in FIG. 1, the control unit 24 compares the measured value of the idle rotation speed, which is the engine rotation speed input when the engine is cold, from the detection signal with a fuel supply setting value set and stored in advance. It has a function of determining the fuel properties and, when the fuel properties do not match the set value, controlling the fuel supply amount to increase or decrease, that is, to increase or decrease the amount of fuel supplied for acceleration.

In other words, the control unit 24 is located in the area A shown by the diagonal line in FIG. If it is located within the A region, it is determined that the fuel properties match the set value, and if it is not located within the A region, for example, the idle speed is less than the A region, the set value is determined. It is determined that the fuel properties do not match the values. If it is determined that the fuel properties do not match the set values, as shown in Figure 1 (a) and (C), when transitioning from idling operation to driving operation, the hatched area in Figure 1 is As shown in region C, the control is performed to perform acceleration increase correction of fuel.

Next, the effect will be explained.

When the internal combustion engine 4 is cold, the control section 24 receives an intake air amount signal which is an air flow signal from the air flow meter 22, an 02 sensor signal which is an oxygen concentration from the 02 sensor 36, engine speed, cooling water temperature, and intake air amount signal. Various signals such as air temperature, throttle signal, and vehicle speed signal are input.

Then, the measured value based on the detection signal of the idle rotation speed inputted to the control unit 24 is a set value A that is set and stored in advance.
It is determined whether or not the engine is located within the range, and if the idle speed is less than the A range and is not within the A range, it is determined that the fuel properties do not match the set value, and as shown in FIG. 1(a), (
As shown in C), when the engine shifts from idling to running, the fuel acceleration increase correction is performed as shown in the shaded area C in FIG. 1.

As a result, the fuel properties can be accurately determined based on the measured value of the detection signal of the idle rotation speed input to the control unit 24 when the engine is cold, and if the fuel properties do not match the set value after the determination, the amount of fuel is accelerated and increased. Control can be performed to perform correction, appropriate driving performance can be ensured, and good driving performance can be obtained.

In addition, when the vehicle is accelerated after starting, the acceleration increase correction can be performed to prevent the air-fuel ratio from becoming steeper, as shown in Figure 1 (C), thereby improving the engine's revving and reducing the engine speed. This prevents the vehicle from falling and prevents the problem of poor drivability due to heavy breathing.

Furthermore, since the fuel supply control of the internal combustion engine 4 can be handled by simply changing the software in the control section 24, the configuration of the fuel supply control device 2 is not complicated and manufacturing is easy.
It is economically advantageous because the cost can be kept low.

Note that the present invention is not limited to the above-described embodiments, and various modifications can be made.

For example, in the embodiment of the present invention, the amount of fuel increase when performing fuel acceleration increase correction is set as desired, but the amount of fuel that is It can also be set to an increasing amount.

In addition, in the embodiment of the present invention, the engine speed input to the control unit is used when determining the fuel properties, but the engine speed, intake negative pressure, and intake air amount from the air flow meter are used. (TP value), and it is also possible to determine the fuel properties based on intake negative pressure or intake air amount.

Furthermore, in the embodiment of the present invention, the fuel is configured to perform acceleration fuel increase correction in order to improve drivability. It is also possible to perform control to improve driveability through correction.

Furthermore, in the embodiment of the present invention, in the case of an idle rotation speed in the A area with no drips, which is not located within the A area, it is determined that the fuel properties do not match the set value, and the idle operation is shifted to the running operation. In this case, the control was performed to correct the fuel acceleration increase, but when the set value was determined based on poor quality fuel, there were cases where the idle rotation speed exceeded the A area, which was not within the A area, and the idle rotation speed If the number exceeds region A, if control is performed to correct the acceleration reduction of fuel, good drivability can be maintained without deteriorating exhaust gas.

[Effects of the Invention] As explained in detail above, according to the present invention, the engine speed, intake negative pressure, and intake air amount, which are input when the engine is cold, are determined based on a detection signal of any one of the engine speed, intake negative pressure, and intake air amount. We have provided a control unit that determines the fuel properties by comparing them with the stored fuel supply setting values, and controls the fuel supply amount to increase or decrease when the fuel properties do not match the set values. The fuel properties can be accurately determined based on the detected signals of the engine speed, intake negative pressure, and intake air amount in the engine operating state that are input to the engine, and after the determination, it is possible to detect fuel that does not match the set value. If this is the case, it is possible to perform control to correct the acceleration increase in fuel, thereby ensuring appropriate driving performance and obtaining good driving performance. Also,
Since the problem can be solved by only changing the software in the control section, the structure of the fuel supply control device does not become complicated, it is easy to manufacture, and the cost can be reduced, which is economically advantageous.

[Brief explanation of drawings]

1 to 4 show an embodiment of the present invention, FIG. 1 shows acceleration increase correction by the control unit of a fuel supply control device for an internal combustion engine, and FIG. 1(a) is a time chart of the engine rotation speed;
Figure 1 (b) is a time chart of water temperature, Figure 1 (C) is a time chart of acceleration increase correction, Figure 2 is a schematic configuration diagram of the fuel supply control device for the internal combustion engine, and Figure 3 is the fuel for the internal combustion engine. A schematic block diagram of the supply control device, FIG. 4 is a diagram showing the input and output status of the control section. FIG. 5 is a diagram showing the relationship between water temperature correction and water temperature during fuel increase correction showing another embodiment of the present invention. In the figure, 2 is a fuel supply control device, 4 is an internal combustion engine, and 6 is a fuel supply control device.
is the air filter, 8 is the surge tank, 10 is the intake passage,
12 is an exhaust passage, 16 is an oil filter, 18 is a pressure regulator, 20 is a fuel tank, 22 is an air flow meter, and 24 is a control unit. License Applicant: Suzuki Motor Co., Ltd. Patent attorney
Engraving of Yoshimi Saigo Figure 1 Question 3 Figure 2 Figure 4 Figure 4 Itaku -Water > N - Southern Procedures (Hoshosho (Method) March 20, 1990 1, Indication of the incident Patent Application No. 2-028913 No. 2, Name of the invention Fuel supply control device for internal combustion engine 3, Relationship to the case of the person making the amendment Patent applicant address 300 Takatsuka, Kamimura, Hamana-gun, Shizuoka Prefecture Name (2)
08) Lead Automobile Industry Co., Ltd.

Claims (1)

[Claims] 1. In a fuel supply control device for an internal combustion engine that has a control unit that inputs various detection signals of the internal combustion engine and controls the fuel supply amount, the engine speed, intake negative pressure, and intake air amount in the engine operating state are input when the engine is cold. The fuel property is determined by comparing the measured value from one of the detection signals with the preset and memorized fuel supply setting value, and if the fuel property does not match the set value, the fuel supply amount is increased or decreased. 1. A fuel supply control device for an internal combustion engine, comprising a control section for controlling the fuel supply to an internal combustion engine.