JPS59162312A - Electronically controlled engine - Google Patents

Abstract

PURPOSE:To provide the opening/closing timing and the lift characteristic optimum for current operating conditions by opening and closing a suction and an exhaust valve electromagnetically in accordance with the output of a micro- computer, in which the operating conditions are entered. CONSTITUTION:Engine condition signals to represent degree of accelerator opening, engine temp. and number of revolutions and atmospheric condition signals to represent atmospheric pressure, temp., etc. are entered in a micro-computer 11, and these data are sampled at every specific crank angle to serve determination of the rate of injection from the injector, opening/closing timing of the suction and exhaust valves and the lift characteristic. Drive signals are sent to solenoids 8, 9 of the suction and exhaust valves 5, 6 at every specific crank angle, and a drive signal is fed to the injector when the suction valve 5 is opened. Now the fuel is injected. According to this arrangement, opening and closing of the suction and exhaust valves are performed electromagnetically in the optimum conditions.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electronically controlled engine, and particularly to an electronically controlled engine that controls intake and exhaust valves according to the operating state of the engine.

Conventionally, the intake and exhaust valves of an internal combustion engine have been operated via a link mechanism consisting of a camshaft interlocked with a crankshaft, a rotary rod, a rocker arm, and the like. Therefore, the intake and exhaust valves driven via the above-mentioned camshaft always have a constant valve opening timing and a constant valve opening angle width, regardless of the operating state of the internal combustion engine. Therefore, it is difficult to adapt the configuration of this type of internal combustion engine to the valve opening/closing characteristics that change from low load to high load.

In other words, at high speeds, the valve overlap of the intake and exhaust valves is set large to improve intake inertia efficiency, and at low speeds, the intake negative pressure increases. In order to prevent combustion gas from flowing backwards once it has been discharged, it is necessary to reduce the valve overlag.

Furthermore, the lift characteristics of the valve must be small near bottom dead center when the piston speed is low, and large lift when the piston speed is high at intermediate positions.

However, with the conventional cam drive method described above, these adjustments are impossible due to its method.

The present invention has been made with the aim of solving the above-mentioned problems, and includes an electronically controlled engine that calculates and outputs optimal conditions using a micro combinator (hereinafter referred to as MPU) according to the operating state. is intended to provide.

In addition, in the present invention, the intake and exhaust valves, which were conventionally driven via the crankshaft, are magnetically controlled to open and close by the output from the MPU, and the opening and closing timing and lift characteristics of the intake and exhaust valves are also controlled according to the operating state. The engine output is also adjusted by making it variable and adjusting the opening degree of the intake and exhaust valves.

Examples will be described below with reference to the drawings. FIG. 1 is a configuration diagram of an embodiment of an electronically controlled ennon according to the present invention.

In FIG. 1, 1 is an engine cylinder, 2 is a piston, and 3 is a combustion chamber. Mixed gas from an intake pipe 4 is sucked into the combustion chamber 3 via an intake valve 5, and after being combusted there, It is discharged through the exhaust pipe 7 via the exhaust valve 6. 8 and 9 are renoids and drive unit 10
The drive unit 10 is connected to an MPU 11
It is operated by the calculation result of . Furthermore, operating conditions such as accelerator opening, engine temperature, rotational speed, atmospheric pressure, and atmospheric temperature are input to MPU t i and subjected to arithmetic processing. Then, a series of controls described below are performed by a drive signal from the drive unit 10.

In other words, when the rotation speed is low, the valve overlap is reduced to prevent backflow of combustion gas due to the large intake negative pressure, increasing combustion efficiency, and when the rotation speed is high, the valve overlap is increased to reduce the intake air. In addition, the lift characteristics of the valve are variable so that the piston speed is small and the lift is small near the bottom dead center, and the lift is large when the piston speed is at an intermediate position. Control is exercised. Furthermore, when adjusting the engine output, for example, during idling, the valve lift is small and the opening/closing timing is delayed, and during acceleration, the valve lift is increased and the opening/closing timing is adjusted to match the rotation speed. , adjusted to be faster. In the case of high output, the valve lift is increased to maximize the inertial efficiency of the intake air and reduce pumping loss, and on the other hand, during deceleration, the internal pressure of the cylinder is increased to achieve maximum strength. Adjusted to produce an engine braking effect. And these series of operations are performed by MP
This is performed by arithmetic processing by U11. Note that the first
Although not shown in the figure, the 7-well injector is also controlled together with the control of the intake and exhaust valves.

FIG. 2 is a block diagram showing the control system of the electronically controlled engine. In FIG. 2, the accelerator degree is input to a potentiometer indicated by 12 and converted into an electrical signal, which is input to the control unit 13. As described above, the control unit 13 controls atmospheric conditions such as atmospheric pressure and atmospheric temperature, intake pressure, rotational speed, engine temperature, etc.
Engine conditions such as crank angle position and mixture ratio A/F are inputted, and a series of arithmetic processing is performed to satisfy all of the previously described conditions, and intake and exhaust valve control and fuel control by the injector are performed.

FIG. 3 shows control signals for controlling the lift amount and opening/closing timing of the intake and exhaust valves, which are controlled by the on/off time ratio of the output pulse train from the rubber control unit 13. Based on the injector injection amount calculated at the same time, fuel injection is performed in synchronization with the valve opening/closing timing.

FIG. 4 is a flowchart for explaining the operation. Fourth
Figure (a) shows the process of calculating the opening/closing timing of the valve and the injection amount of the injector.
In step 2, each data is subjected to sampling processing. Then, the process moves to step 43, and the opening/closing timing of the intake and exhaust valves and the on/off time of each valve are calculated according to the sanfried information, and then the process moves to step 44, where the process ends.

In FIG. 4(b), every 180° crank angle is detected in step 41', and the process moves to the stellar 7'42' to output a drive signal to the intake/exhaust valve lunoid.

On the other hand, in FIG. 4(c), all opening timings of the intake and exhaust valves are detected at step 77'41//, and based on this, a drive signal to the injector is output at step f42''.

These routines are subjected to interrupt processing. In addition,
The above explanation shows the case of a 4-cylinder engine.

As explained above, according to the present invention, the engine condition and atmospheric condition are input to the CPU, and the valve opening timing, lift amount, and injection amount of the injector 7 are determined by a series of calculation processes. Not only does it eliminate the link mechanism for operating the valve, but it also provides variable adjustment of the valve overrazzo period, reduced pumping loss, sharpness during acceleration and deceleration, and smooth engine braking, all of which are ideal for Ennon. We can provide electronically controlled engines.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram of an embodiment of an electronically controlled engine according to the present invention, Fig. 2 is a block diagram showing a control system of the electronically controlled engine, and Fig. 3 is a control signal that controls the lift amount and opening/closing timing of the intake and exhaust valves. FIG. 4 is a chart from 70 to 70 for explaining the operation. 1...Cylinder 2...Piston 3...
Combustion chamber 4...Intake pipe 5...Intake valve
6...Exhaust valve 7...Exhaust W
8, 9...Solenoid 10...Drive unit 11...Microcomputer 12...Potentiometer 13...Control unit Patent applicant Mikuni Kogyo Co., Ltd. Agent Patent attorney Toishi Norihito Figure 4 (α) (b)

Claims (1)

[Claims] In electronically controlled ennons that control the opening and closing of engine intake and exhaust valves using electromagnetic force, the engine operating conditions and atmospheric conditions are input and data sampling is performed at every predetermined crank angle to determine the intake and exhaust valve opening/closing timing, lift characteristics, on/off status, etc. A means for determining a time ratio and an injection amount of the injector, a means for outputting a drive signal to the solenoid of the intake and exhaust valves at every predetermined crank angle, and a means for outputting a drive signal to the injector when the intake valve is opened. An electronically controlled engine characterized by: