JPH04191438A - Rotating speed control device for decelerating time - Google Patents

Abstract

PURPOSE:To thin the excessively densified air-fuel ratio caused by intake pulsation by intermittently injecting and supplying a fuel quantity calculated from engine rotating speed and throttle opening by a fuel injection valve, at the time of decelerating operation of an internal combustion engine, and conducting the control so as to rationalize the air-fuel ratio. CONSTITUTION:A fuel injection valve 24 is connected to a control part 44 through a resistor 42. A fuel pump 34 is connected to the control part 44 through a pump relay 46 to feed and cut the power source from a battery 58. Further, an ignition circuit 26 to detect the engine rotating speed, a throttle opening sensor 48 for detecting the throttle opening of a throttle valve 22 and others are connected to the control part 44. In the control part 44, in a determined engine rotating speed area and a determined throttle opening area at the time of decelerating operation of an internal combustion engine, the fuel quantity calculated from the engine rotating speed and the throttle opening is intermittently injected and supplied by the fuel injection valve 24 and controlled so as to rationalize the air fuel ratio.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a deceleration/maintenance rotation speed control device, and in particular, to an apparatus which can optimize the air-fuel ratio during deceleration operation of an internal combustion engine and prevent misfires and seizures of the internal combustion engine. The present invention relates to a deceleration/rotation speed control device that can prevent the problem from occurring.

[Conventional technology]

2. Description of the Related Art Some internal combustion engines detect an engine operating state and inject and supply a fuel amount calculated from the detected value using a fuel injection valve. A device for injecting and supplying fuel to an internal combustion engine using a fuel injection valve is disclosed in Japanese Patent Application Laid-Open No. 63-30215.
There is a disclosure in Publication No. 8. What is disclosed in this publication is to calculate the fuel injection amount by correcting the basic injection amount by the deceleration correction amount during deceleration operation of the internal combustion engine, and to calculate the fuel injection amount when the fuel injection amount is less than a predetermined value and the basic injection amount is the predetermined value. In the above cases, by correcting the fuel injection amount so that it does not reach the predetermined value and limiting the fuel injection amount to the predetermined value, injection below the predetermined width plate, which deteriorates the accuracy of the fuel injector, can be avoided. This system suppresses fluctuations in the air-fuel ratio, prevents engine stalling, improves exhaust emission characteristics, and improves drivability.

[Problem that the invention seeks to solve]

Incidentally, an internal combustion engine, particularly a two-stroke internal combustion engine having a peak output characteristic in which the maximum output is prominent on the high rotation side, produces a unique intake pulsation during deceleration operation. This intake pulsation causes irregularities in the intake flow, so that the intake flow is not constant.

In this case, if the internal combustion engine is equipped with a carburetor, the carburetor sucks out fuel using the principle of atomization using an air flow and mixes the air and fuel, and the air-fuel ratio of this mixture is By following the air amount, the intake pulsation during the deceleration operation extremely deteriorates the specific fuel consumption rate, resulting in an incorrect combustion region. Furthermore, in a two-stroke internal combustion engine having beaky output characteristics, the output rises rapidly from the output trough, and the required air amount becomes transiently large.

For this reason, a two-stroke internal combustion engine having beaky output characteristics has a problem in which the air-fuel ratio deviates significantly from the flammable range in a predetermined engine speed range and a predetermined throttle opening range during deceleration operation, causing a misfire. This misfire takes time to recover from, especially while the vehicle is running.

Further, the internal combustion engine detects the engine rotation speed and the slow / ) small opening, and the fuel amount calculated from the detected engine rotation speed and the slow / ) small opening is injected and supplied by the fuel injection valve. In some cases, air and fuel have independent forms. Therefore, when the internal combustion engine is in deceleration operation, if the fuel amount calculated from the map between the steady engine speed and the throttle opening is injected and supplied by the fuel injection valve, it will follow the large transient changes in the air amount during deceleration operation. There is a problem that cannot be solved. In other words, when extreme fluctuations occur in the intake pulsation, the amount of air fluctuates from the map of steady engine speed and throttle opening, and the air-fuel ratio becomes excessively enriched, resulting in an inappropriate air-fuel ratio, which can lead to combustibility. There is an inconvenience that it may deviate far from the range and cause a misfire.

This misfire condition during deceleration operation will be explained with reference to FIGS. 5 and 6.

In Fig. 5, A is the intake pulsation in the full throttle opening range, B is the intake pulsation in the decreasing throttle opening range, and C is the intake pulsation when the throttle opening is held at an arbitrary opening from fully open to closed. The change in intake pulsation, D, is the stable pulsation when the throttle opening is held at an arbitrary opening. In addition, ``A'' is the pulsation width in the full throttle opening range, and ``A'' is the pulsation width when the throttle opening is held at an arbitrary degree.

Normally, when the throttle opening changes from A to D, the change from A to the mouth with the same width as the pulse changes gradually as shown in B, and then passes through C and transitions to state D.

However, during deceleration operation of an internal combustion engine, especially when decelerating a two-stroke internal combustion engine with beaky output characteristics,
When there is a sudden rise in output from a trough or in an incorrect combustion region, it fluctuates based on the map between engine speed and throttle opening.

As shown in Fig. 6, such a state does not occur during steady operation or acceleration operation, but during deceleration operation, especially in the diagonally shaded area where the deceleration lines shown in ■ and ■, that is, at a certain throttle opening. This occurs in the range set by the engine speed range and the engine speed range.

Furthermore, as a control device during deceleration, there is also a device that controls fuel power. However, if fuel cut is controlled during deceleration operation, there is a risk of seizure of the internal combustion engine, and if the fuel cut is controlled for a long time, a misfire will occur and recovery will take time, resulting in sluggishness during the next acceleration. There is.

[Purpose of the invention]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to realize a deceleration and rotational speed control device that can optimize the air-fuel ratio during deceleration operation of an internal combustion engine and prevent misfires and seizures of the internal combustion engine.

[Means for solving problems]

In order to achieve this object, the present invention provides a method for controlling a predetermined engine speed range and a predetermined throttle opening during deceleration operation of an internal combustion engine in which a fuel amount calculated from an engine speed and a throttle opening is injected and supplied by a fuel injection valve. The present invention is characterized in that a control means is provided for controlling the air-fuel ratio by intermittently injecting and supplying the amount of fuel calculated from the engine speed and the throttle opening using the fuel injection valve in the opening range.

[Effect]

According to the configuration of the present invention, the control means controls the amount of fuel calculated from the engine speed and the throttle opening in a predetermined engine speed range and a predetermined throttle opening range during deceleration operation of the internal combustion engine to the fuel injection valve. By performing intermittent injection supply and controlling to optimize the air-fuel ratio, it is possible to reduce the air-fuel ratio that becomes overrich due to intake pulsation during deceleration operation of the internal combustion engine.

〔Example〕

Next, embodiments of the present invention will be described in detail based on the drawings.

FIGS. 1 to 4 show an embodiment of a speed reduction and rotational speed control device according to the present invention. In Fig. 4, 2 is an internal combustion engine, 4 is a crank chamber, 6 is a crankshaft, 8 is a combustion chamber, 1
0 is a piston, and 12 is a spark plug. The internal combustion engine 2 in this embodiment is a so-called two-stroke internal combustion engine in which two strokes, a scavenging and compression stroke and an expansion and suction stroke, are performed during one rotation of the crankshaft 6, and these strokes constitute one cycle. Further, this internal combustion engine 2 is mounted on a vehicle (not shown).

A throttle body 16 is connected to a crankcase 14 forming a crank chamber 4 of the internal combustion engine 2 .

An air cleaner box 18 is connected to the throttle body 16. An intake passage 20 formed by a throttle body 16 and an air cleaner box 18 communicates with the crank chamber 4 . An intake passage 20 formed in the throttle body 16 is provided with a throttle valve 22 and a fuel injection valve 24 directed toward the crank chamber 4 .

Further, the spark plug 12 provided in the combustion chamber 8 is connected to an ignition circuit 26. The ignition circuit 26 causes the ignition plug 12 to spark in response to a signal input from a pink-up 28 that is rotationally driven by the crankshaft 6.

The internal combustion engine 2 in this embodiment has two slot/nottle bodies 1 for each combustion chamber 8, as shown in FIGS.
6 and 16 are provided in communication with the crank case 14, respectively, and each throttle body 16 and 16 is provided in communication with a single air cleaner box 18. As a result, each throttle body 16 has its own intake passage 2.
0 and 20 are formed, and throttle valves 22 and 22 are provided respectively, and each throttle body 16
・Fuel injection valves 24 and 24 are provided in the fuel injection valves 16 and 16, respectively.

The intake passage 2 is regulated by the throttle valve 22.
The air flowing through the air and the fuel injected and supplied by the fuel injection valve 24 form a mixture that flows into the crank chamber 4, is supplied to the combustion chamber 8, is ignited and burnt by the spark plug 12, and is passed through the exhaust passage (not shown). is discharged to the outside. This combustion causes the piston lO to drive the crankshaft 6. The driving force of the internal combustion engine 2 taken out by the crankshaft 6 is transmitted, for example, from a clutch mechanism (not shown) to a traveling mechanism via a transmission mechanism to drive a vehicle (not shown).

The fuel injection valve 24 is communicated with a fuel tank 32 through a fuel supply passage 30. A fuel pump 34 for pumping fuel under pressure and a fuel filter 36 for removing dust from the fuel are provided in the middle of the fuel supply passage 30. Also,
The fuel injection valve 24 is communicated with the fuel tank 32 through a fuel pressure adjustment passage 38 . This fuel pressure adjustment passage 38
A fuel pressure regulating valve 40 is provided in the middle. The fuel pressure regulating valve 40 controls the fuel pressure to be fed to the fuel injection valve 24 through the intake passage 20 downstream of the throttle valve 22.
The intake pressure is adjusted to a predetermined pressure, and excess fuel is returned to the fuel tank 32 through the fuel pressure adjustment passage 38.

The fuel injection valve 24 is connected to a control section 44 as a control means via a resistor 42. Further, the fuel pump 34 is connected to a control section 44 via a pump relay 46, and is supplied with and cut off from power from a P/7 battery 58, which will be described later.

The control unit 44 includes an ignition circuit 26 for detecting the engine speed, a throttle opening sensor 48 for detecting the throttle opening of the throttle valve 22, and a water temperature sensor 50 for detecting the temperature of the cooling water of the internal combustion engine 2. , an intake temperature sensor 52 that detects intake air temperature, and an atmospheric pressure sensor 5 that detects atmospheric pressure.
4 and are connected. This atmospheric pressure sensor 54 is provided within the control section 44 .

The control unit 44 also includes a control unit relay 5 that supplies and disconnects power.
6 to a battery 58. The control unit relay 56 is connected to the switch 58 via an ignition switch 60. The control unit relay 56 is turned on and off by the ignition switch 60 to supply and disconnect power to the control unit 44 . In addition, the code|symbol 62 is control part relay 56
This is a control section relay fuse interposed between the control section 58 and the control section 58. Code 64 is ignition switch 7 switch 60
This is an ignition switch fuse interposed between the battery 58 and the battery 58. Further, reference numeral 66 is a pump relay fuse interposed between the pump relay 46 and the relay 58.

The control unit 44 drives and controls the fuel injection valve 24 based on signals input from the sensors 26, 48 to 54.

That is, the control unit 44 controls the fuel injection valve 24 to inject and supply the amount of fuel calculated from a map of the engine speed and throttle opening according to the basic fuel injection control.

In this way, during deceleration operation of the internal combustion engine 2 in which the fuel amount calculated from the engine speed and the throttle opening is injected and supplied by the fuel injection valve 24, the amount of fuel calculated from the engine speed and the throttle opening is injected into the predetermined engine speed range Ne and the predetermined throttle opening range. A control section 44 is provided as a control means for controlling the air-fuel ratio by intermittently injecting and supplying the amount of fuel calculated from the engine speed and the throttle opening by the fuel injection valve 24 at α.

That is, when the engine speed and the throttle opening are in the predetermined engine speed range Ne and the predetermined throttle opening range α during deceleration operation of the internal combustion engine 2, the control unit 44 controls the engine speed and the throttle opening to By intermittent injection supplying and thinning out the amount of fuel calculated from the fuel injector 24, the air-fuel ratio is prevented from becoming excessively enriched due to intake pulsation during deceleration operation, and the air-fuel ratio is optimized. be.

Next, the operation will be explained according to FIG.

When the control starts (100), the control unit 44 determines whether or not the internal combustion engine 2 is in deceleration operation, for example, from the amount of change in the engine speed and the throttle opening (101).

When the internal combustion engine 2 is not in deceleration operation (101: NO) in this blade 1 break (101), the end (102) is reached. In the judgment (101), if the internal combustion engine 2 is in deceleration operation (101: YES), it is judged (103) whether the engine speed is within a predetermined engine speed range Ne.

In this judgment (103), if the engine speed is not within the predetermined engine speed range Ne (lO32N○), the end (
IO2). In the judgment (103), if the engine speed is within the predetermined engine speed range Ne (103: Y
ES) means that the throttle opening is within a predetermined throttle opening range α
(104).

In this judgment (104), if the throttle opening is not within the predetermined throttle opening range α (104: NO), the process becomes the end (102). In the judgment (104), if the throttle opening is in the predetermined throttle opening range α (1
04: YES) returns the fuel amount calculated from the engine speed and throttle opening to the intermittent injection supply (105)L, (103) by the fuel injection valve 24.

In this way, the control unit 44 controls the fuel amount calculated from the engine speed and the throttle opening in the predetermined engine speed range Ne and the predetermined In the throttle opening range α, the fuel amount calculated from the engine speed and the throttle opening is intermittently injected and supplied by the fuel injection valve 24 to control the air-fuel ratio to be appropriate.

That is, during deceleration operation of the internal combustion engine 2, the control unit 44 controls the engine speed and the throttle opening to fall within a predetermined engine speed range Ne and a predetermined throttle opening range α shown by diagonal lines in FIG.
In this case, the amount of fuel calculated from the engine speed and throttle opening is intermittently supplied by the fuel injection valve 24 to reduce the amount of fuel (for example, the injection is performed once every two times or once every third time). By thinning out the air-fuel ratio, it is possible to prevent the air-fuel ratio from becoming excessively enriched due to intake pulsation during deceleration operation, thin the air-fuel ratio, and optimize the air-fuel ratio.

Therefore, it is possible to optimize the air-fuel ratio during deceleration operation of the internal combustion engine 2, thereby making it possible to prevent misfires during deceleration operation. In addition, unlike fuel cut control during deceleration operation, the internal combustion engine does not seize, and misfires due to the long fuel cut control time can be prevented. It does not cause any sluggishness.

〔Effect of the invention〕

As described above, according to the present invention, the control means injects the amount of fuel calculated from the engine speed and the throttle opening in a predetermined engine speed range and a predetermined throttle opening range during deceleration operation of the internal combustion engine. By controlling the air-fuel ratio to be appropriate through intermittent injection supply using the valve, it is possible to eliminate the air-fuel ratio that becomes excessively enriched due to intake pulsation during deceleration operation of the internal combustion engine.

Therefore, it is possible to optimize the air-fuel ratio during deceleration operation of the internal combustion engine, thereby preventing misfires during deceleration operation, and preventing seizure of the internal combustion engine and fuel cut-off, such as fuel cut control during deceleration operation. The occurrence of misfires due to a long control time can be prevented, and sluggishness does not occur during acceleration after deceleration.

[Brief explanation of the drawing]

1 to 4 show embodiments of the present invention, FIG. 1 is a schematic diagram of the deceleration/maintenance rotation speed control device, FIG. 2 is a schematic diagram of the fuel injection valve, and FIG. 3 is a control flowchart. FIG. 4 is a schematic configuration diagram of an internal combustion engine equipped with a reduction gear rotation speed control device. Figures 5 and 6 show examples of conditions during deceleration operation, Figure 5 shows changes in intake pulsation with respect to throttle opening, and Figure 6 shows changes in deceleration line with respect to throttle opening and engine speed. FIG. In the figure, 2 is an internal combustion engine, 16 is a throttle body,
18 is an air cleaner box, 20 is an intake passage, 22 is a throttle valve, 24 is a fuel injection valve, 26 is an ignition circuit, 44 is a control unit, 48 is a throttle opening sensor, 50 is a water temperature sensor, 52 is an intake air temperature sensor, 54 5 is an atmospheric pressure sensor, 56 is a control unit relay, 58 is a battery, and 60 is an ignition switch. Figure 2 Figure 3

Claims (1)

[Claims] 1. The amount of fuel calculated from the engine speed and the throttle opening is injected and supplied by the fuel injection valve to the engine speed in a predetermined engine speed range and a predetermined throttle opening range during deceleration operation of the internal combustion engine. 1. A rotational speed control device during deceleration, characterized in that a control means is provided for controlling the air-fuel ratio by intermittently injecting and supplying a fuel amount calculated from a throttle opening degree using a fuel injection valve.