JPS6043162A - Suction air controlling device for multi-cylinder engine - Google Patents

Abstract

PURPOSE:To uniform the suction air amount and air-fuel ratio of respective cylinders by a method wherein an opening and closing valve is operated by a pressure difference between the averaged vacuum of respective cylinders and the suction vacuum of respective cylinders. CONSTITUTION:The suction vacuums of respective cylinders are averaged in a vacuum tank 11 and the averaged vacuum acts on a pressure regulator 17. By this method, the fuel pressures of injectors of respective cylinders are averaged. The averaged vacuum in the vacuum tank 11 acts in an actuator 3 into the direction to close the opening and closing valve 4 while the suction vacuums of respective cylinders act in the actuator 3 into the direction to open the opening and closing valve 4. When the vacuum applied to the vacuum chamber 13 of the actuator 3 is smaller than the averaged vacuum of the vacuum tank 11, which is applied to the vacuum chamber of the actuator 3, the opening degree of the opening and closing valve 4 is reduced. According to this method, the area of a sub suction air path 2 may be decreased, deterioration of suction vacuum in the main suction air path 1 may be supplemented and a predetermined amount of air may be fed from a suction chamber 6.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a fuel 1. ! l U(I IIJt type intake control in a multi-cylinder engine - JAifl, particularly related to equalizing the air-fuel ratio of each cylinder.

When the fuel supply system of a multi-cylinder engine is a multi-point fuel injection system, if the intake air in each cylinder differs due to navigational constraints, etc., the fuel injection 1d will be biased to each cylinder 1n, so each The air-fuel ratio of the air-fuel mixture in the cylinders differs, which adversely affects driving performance, emissions, etc.

Therefore, in order to deal with such non-uniformity of the air-fuel ratio of each cylinder, conventional methods have been used to correct the fuel pressure of the injector fuel system, as shown in Japanese Utility Model Application Publication No. 54-44821 (1). However, this prior art system is undesirable because the fuel pressure in the injector constantly fluctuates, and there are also problems with zero fuel pressure (at high revolutions).

In view of the problem caused by the difference in the intake air 1 of each cylinder in a fuel injection plastic multi-cylinder engine, the present invention proposes that correction is made on the injector side. It is an object of the present invention to provide an air intake control device for a multi-cylinder engine that equalizes the air-fuel ratio of the cylinders.

For this purpose, the present invention is based on the fact that the intake air 71 of each cylinder is directly related to the intake negative pressure in the intake passage. i;) The area of the intake passage of each cylinder is changed based on the differential pressure from the intake pressure [1]. This causes the intake negative pressure and the intake air I'lk to
The purpose of this is to equalize the

Hereinafter, one embodiment of the present invention will be specifically described with reference to the drawings. In Fig. 1 and Fig. 2, 'C1 to C4 are the combustion chambers of the first to fourth cylinders, and when the first cylinder is represented by 31, the intake system of the combustion chamber C1 is connected to the main intake passage 1. It has an auxiliary intake passage 2 that branches off from the middle, and an on-off valve 4 equipped with a diaphragm type (diaphragm type) eater 3 is installed in this auxiliary intake passage 2, and the downstream side of the throttle body 5 controls a predetermined capacity. It is configured to communicate with the main and sub-intake passages 1 and 2 via an intake chamber G. Further, an injector 8 and a negative pressure outlet 1]9 are provided immediately before the intake valve 7 of the main intake passage 1, and these are constructed in exactly the same way in the other cylinders.

As shown in FIG. 3, the negative pressure outlet 9 is connected to the passage 1.
0 to J, Ribaki: L-Communicate with the tank 11 to average the negative pressure of each cylinder, and actuate], - One negative pressure chamber 13 partitioned by the diaphragm 12 at 3.
It is connected to [no]. On the other hand, a passage 14 from the vacuum tank 11 communicates with the other negative pressure chamber 15 of the actuator 3, and further communicates with a pressure regulator 17 provided in the fuel passage 16 of the injector 8 to adjust the fuel pressure. .

To explain the operation of the intake control device configured in this way, the intake negative pressure of each cylinder is averaged in the vacuum tank 11, and this averaged negative pressure acts on the pressure regulator 17. The fuel pressure in the injector 8 of the Raku cylinder is also averaged.Furthermore, this averaged negative pressure in the vacuum tank 11 acts on the actuator 3 in the direction of closing the on-off valve 4. The intake negative pressure of the cylinder is applied to the on-off valve 4 in the actuator T-3.
Acts in the direction of opening. Therefore, if both negative pressures are difficult under the initial conditions, the on-off valve 4 is set to a certain 17flt mark. In this case, the negative pressure chamber 13 of the actuator 3
When the f1 pressure becomes smaller than the averaged negative pressure jζ of the vacuum tank 11 applied to the negative pressure chamber 15 of the actuator 3, the pressure of the on-off valve 4 is reduced. As a result, the area of the auxiliary intake passage 2 of the intake system is reduced, and the above-mentioned decrease in suction negative pressure is compensated for by the main intake passage 1.
A predetermined amount of air is inhaled from.

Another 7? Kuji 1. If the negative pressure applied to both angular pressure chambers 13 and 15 of the eta 3 becomes the opposite phenomenon to the above case,
The opening degree of the Di]rJ1 valve 4 is increased to prevent the intake corner of the main intake passage 1 from becoming rounded, and to prevent a predetermined amount of air 11 from the intake chamber 6.
is inhaled. In this way, the intake air ttI in each cylinder is equalized to the intake negative pressure tt, and the pressure ray 1
By equally injecting fuel from the injector 8 to each cylinder at the fuel pressure averaged by the one-notor 17, the mixture air-fuel ratio of each cylinder is made uniform.

As is clear from the above explanation, the present invention equalizes the intake negative pressure of each cylinder in the Taki-Tsuri engine and improves the intake air! Since the air-fuel ratio of each cylinder is made uniform, the air-fuel ratio of each cylinder is effectively made uniform in the injection system of Marbeboin]~. In addition, the variation in harmful IJI gas is reduced and the exhaust gas purification device can be simplified.
Knocking becomes less likely to occur and its molecular ignition 11. 'l]
Advance angle control of υI improves output and improves fuel efficiency. In addition, injector 8 has a large influence on the air-fuel ratio.
Since it does not change the side, there is little effect from malfunction.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of the apparatus according to the present invention;
FIG. 2 is a schematic plan view of the same, and FIG. 3 is a circuit diagram of suction negative pressure. 01-C4... Combustion chamber of each cylinder, 1... Main intake passage, 2... Sub-intake passage, 3... Actuator, 4...
... Opening/closing valve, 8... Injector, 9... Negative pressure extraction [1, 10, 14... Negative pressure passage, 11... Vacuum tank. Temporary Applicant Fuji Heavy Industries Co., Ltd. Agent Patent Attorney Makoto Kobashi Ben Umen (!I! :t: Susumu Muratsuki)

Claims (1)

[Claims] In the intake system of each cylinder, a main intake passage and a sub-intake passage branching from the main intake passage are installed (J). A multi-cylinder air intake control device characterized by operating the opening/closing valve according to the differential pressure between the intake negative pressure of each cylinder and equalizing the intake air pressure of each cylinder. .