JPS58158362A - Air suction device for engine - Google Patents

Abstract

PURPOSE:To reduce the energy required to operate an oxygen content enriching device and improve the fuel consumption of an engine by an arrangement wherein the oxygen content enriching device is actuated when the engine is decelerating, and the oxygen-enriched air obtained during the deceleration is stored temporarily. CONSTITUTION:An oxygen content enriching device 13 comprises a casing having a material adapted to transmit only oxygen in the air or a greater amount of oxygen than nitrogen, a normal air inlet port 15a, an outlet port 15b for oxygen rich air and an exit port 15c for nitrogen rich air; a pump P1 installed in upstream branch passage 12a; and a pump P2 installed in downstream branch passage 12b. Further, there is provided a control device 23 adapted to make controls so as to supply the oxygen rich air from a storage tank 27 storing the oxygen rich air produced by the oxygen content enriching device 13 into a combustion chamber as and when required.

Description

[Detailed description of the invention] The present invention relates to an engine intake system.

In the past, various efforts were made to improve engine fuel efficiency and increase engine output, such as improving the combustion chamber shape and intake/exhaust ports, improving the fuel supply system, and installing superchargers. As technology advances rapidly, it is no longer possible to achieve significant engine improvements using these physical methods alone.

On the other hand, the composition of air is approximately constant at approximately 21% oxygen and 78% nitrogen, but an oxygen concentration enrichment device that increases the oxygen content ratio in the air allows the oxygen concentration to be lower than that of normal air. For example, Japanese Patent Application Laid-Open No. 5
This is proposed in Japanese Patent No. 6-50253. Unlike a supercharger that physically increases the amount of combustion air to increase the amount of oxygen in the combustion chamber, this method uses an oxygen concentration enrichment device driven directly or indirectly by the engine to increase the amount of oxygen in the combustion chamber. Combustibility is improved by changing the composition of the combustion air itself and increasing the oxygen content of the combustion air to create an atmosphere that is chemically combustible. However, due to excessive loss of energy from the engine to drive the device, and problems with engine durability due to high-temperature combustion, chemical methods have just begun to be applied to engines. is the current situation.

The present invention was made in view of these problems, and an object of the present invention is to provide an engine intake device that can improve the fuel efficiency of the engine and reduce the loss of energy required for the oxygen concentration enrichment device. The gist of the system is to include an oxygen concentration enrichment device that increases the oxygen content ratio in the air, and to supply oxygen-rich air obtained by operating the oxygen concentration device when the engine decelerates to the storage chamber. and a control device for controlling the oxygen-rich air stored in the storage chamber and supplying the oxygen-rich air stored in the storage chamber to the combustion chamber as necessary.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be specifically described with reference to the accompanying drawings.

In Fig. 1, 1 is an engine, 2 is a spark plug, 3 is an intake port, 4 is a fuel injection nozzle, 7 is an air flow meter, 10 is an air cleaner, and 13 is an oxygen concentration enrichment device that increases the oxygen concentration in the air. , are arranged in branch passages 12m and 12b connected in parallel to the intake passage 11 connecting the air cleaner 10 and the intake port 3 of the engine 1. This oxygen concentration enrichment device 13 includes an oxygen permeable membrane 14 made of a material that allows only oxygen in the air or more oxygen to pass through than nitrogen, such as silicone rubber, and a normal air inlet 1.
5a, a casing 15 having an oxygen-rich air outlet 15b1 and a nitrogen-rich air outlet 15C, and a pump P1. It consists of P2. The nitrogen-rich air outlet 15C communicates with a bypass passage 19 provided with a relief valve 18. Blood pump P1. P2 is connected to the engine output shaft via an electromagnetic clutch,
The engagement and engagement of the clutch is controlled by an output signal from a control device 23, which will be described later.

Valves 20 and 21 are provided in the intake passage 11 and the branch passage 12b to increase or decrease the passage area of normal air or oxygen-rich air.
The valves 20 and 21 are interlocked with each other in a reverse opening/closing operation, and are driven by an oxygen concentration controller 22 including a drive motor. The controller 22 is driven by the output from the control device 23, opens and closes the valves 20.21, and depending on the opening angles of the valves 20. Oxygen-rich air having a higher oxygen concentration than normal air is supplied to the combustion chamber of the engine 1 as combustion air. An oxygen concentration detector 24 for detecting the oxygen concentration in this combustion air is disposed in the intake passage 11, and an output terminal of this detector 24 is connected to the control device 23.

The tank 27 that stores oxygen-rich air has its inlet port 2.
7a and the discharge port 27b are each connected to the upstream side of the valve 21 disposed in the branch passage 12b, and valves 25 and 26 are respectively disposed in the flow passage connecting the tank 27 and the branch passage 12b. , these valves 25 and 26 are opened and closed by output signals from the control device 23.

The control device 23 controls the engine 1 as shown in FIG.
Air amount detector (
In response to the output signal from the airflow meter) 7, the basic injection of fuel according to the amount of air is performed at the nozzle 4.
a drive circuit 31 that drives the electromagnetic valves; a determination circuit 32 that determines the operating state of the engine 1; and a valve 18, 25, 26, 29 that receives a signal from the determination circuit 32.
signals to open and close pump P1. Logic circuits 34, 36, 37, 38, 40.41 that output drive signals to P2, and a basic concentration determination circuit 43 that calculates and determines the reference oxygen concentration according to the output signal from the load state determination circuit 42.
A drive circuit 45 that drives the oxygen concentration controller 22 based on the output from the determination circuit 43, and a reference value setting circuit 46 that sets a reference voltage corresponding to the oxygen concentration depending on the load state.
, a comparator 47 that compares the output signals of the oxygen concentration detector 24 and the reference value setting port FI 1146, and a correction circuit 4 that corrects the drive amount of the drive circuit 45 based on the signal from the comparator 47.
4.

When operating an engine equipped with an intake system having the above configuration,
Pumps P1 and P2 are driven by the engine 1, and part of the normal air taken in from the air cleaner 10 is supplied to the casing 15 of the oxygen concentration enrichment device 13 by the action of the pump P1, and then released to the atmosphere from the exhaust port 15C. The air is divided into two: nitrogen-rich air, which is discharged from the exhaust port 15b by the pump P'θ, and oxygen-rich air, which is discharged from the discharge port 15b by the pump P'θ.

On the other hand, when the oxygen-rich air in the storage tank 27 is at a pressure higher than the set pressure, the pressure detector 28 that detects the pressure outputs a high level of output. When the discrimination circuit 32 receives the output signal from the speed detector 5 and the signal from the rotation detector 6 that detects the engine rotational speed or the angular velocity of the crankshaft, etc., and determines that the load is high, the discrimination circuit Since a low level output is output from the first output terminal A and third output terminal C of the section, and a high level output is output from the second output terminal B, the outputs of the AND circuits 36 and 37 are low level. As a result, a high level output signal is output from the OR circuit 38, the solenoid of the relief valve 18 is energized, and the pump P1. The P2 clutch is disengaged and the pump drive stops. In addition, the AND circuit 40
Since the low-level signal inverted by the inverter 1lJ39 and the low-level signal from the third output terminal C are input to the inverter 1lJ39, the output becomes a low level, the valve 25 is closed, and the AND circuit 41 receives a low-level signal from the third output terminal C. A high level output from the pressure detector 28 and a low level output from the first output terminal A of the discrimination circuit 32 are input, and the output becomes a low level and the valve 26 is also closed. 29 is also closed. On the other hand, the load state determination circuit 42 that receives the output signals from the throttle opening degree detector 5 and the rotation detector 6 does not output a signal to the basic concentration determination circuit 43 because the load state is high. Valve 20 arranged in passage 11
is fully open, and the valve 21 disposed in the branch path 12b is fully closed. Therefore, in a high load range, oxygen-rich air is not generated by the oxygen concentration enrichment device 13, and normal air is supplied to the engine 1 from the intake passage 11 through the valve 20.

In order to supply fuel to the engine 1, the basic injection amount determination circuit 30 calculates and determines the amount of fuel to be injected in response to an output signal from an air flow meter (air amount detector) 7, and the engine is driven according to the output signal. This is done by circuit 31 opening and closing the solenoid valve of nozzle 4.

On the other hand, to explain the case where the pressure inside the oxygen-rich air storage tank 27 is below the set value during high load, in this case,
The pressure detector 28 outputs a low level output signal, but the Ok circuit 38 outputs a high level output signal, and the AND circuit 34.
Since the outputs of 40 and 41 are both at a low level, the relief valve 18 is open and the valves 25 and 26 are closed, as in the previous case.
．． 29 are all closed, and pump P1. The drive of P2 remains stopped.

Next, when the opening degree of the throttle valve 8 decreases from this state and the engine 1 enters a deceleration state, the discrimination circuit 32 outputs a high level signal from the third output terminal C because the engine 1 is at high rotation and low load. Since the output of the OR circuit 38 is low level and the pumps P1 and P2 are driven, the relief valve 18 is closed and the output of the AND circuit 40 is low. is high level and valve 2
5 is open, the output of the AND circuit 41 is at a low level, and the valve 26
is closed and there is no output from the load state determination circuit 42, so the valve 20 is fully open and the valve 21 is fully closed. Note that the valve 29 remains closed because the output of the AND circuit 34 is at a low level. Therefore, the engine 1 is supplied with normal air from the air cleaner 10, but the oxygen-rich air enriched by the oxygen concentration enrichment device 13 passes through the valve 25 and is stored in the storage tank 27. Therefore, oxygen-rich air is stored in the storage tank 27.
The pump P1. P2 becomes a load on the engine 1, but since the engine 1 itself rotates due to inertia during deceleration, there is no need for the engine 1 to generate energy for operating the oxygen concentration enrichment device 13.

When the pressure inside the tank 27 reaches the set value, the pressure detector 2
Since the output signal from 8 becomes high level, the circuit 38
jl IJ-F valve 18 is opened by the output signal from
The output signal from the AND circuit 40 causes the valve 25 to close, and the pump P1 to close.

Since the drive of P2 is stopped, oxygen-rich air is not generated from the oxygen concentration enrichment device 13.

Further, when the engine 1 changes from a high rotation and low load state to a low rotation and low load state, the discrimination circuit 32 outputs a high level signal only from the first output terminal A, and outputs a high level signal from the other output terminals B and C.
Since a low level signal is output from IJ IJ-
The fuel valve 18 is open, the valve 25 is closed, the valve 26 is open, and the valve 29 is closed. On the other hand, the oxygen concentration in the combustion air to be supplied to the engine 1 is determined by the output signal from the load state determination circuit 42. 43, the drive circuit 45 drives the oxygen concentration controller 22 in accordance with the output signal, and the valves 20.21 are opened and closed to a predetermined opening angle.

As a result, oxygen-rich air from the storage tank 27 through the valve 21 is mixed with normal air supplied through the valve 20, and oxygen-rich air containing oxygen at a predetermined concentration is supplied to the engine 1. Therefore, since the combustion air contains a larger amount of oxygen than normal air, combustion is promoted and complete combustion occurs, resulting in a reduction in fuel consumption. In addition, in this case as well, the pump P1゜P
2 will be stopped, there will be no load on the engine, and the effective output of the engine will hardly decrease. If the oxygen concentration in the oxygen-rich air supplied to the engine is the set concentration during this low rotation and low load, the above operation will be performed regardless of the correction circuit 44, but if it deviates from the set concentration, for example, the concentration is too high. In this case, an output signal is output from the comparator 47 in response to an output signal from the setting circuit 46 that sets the oxygen concentration according to the output signal from the load state determination circuit 42 and an output signal from the oxygen concentration detector 24. The correction circuit 44 modifies the operating amount of the controller 22 and adjusts the opening angle of the valve 20.21 to reduce the oxygen concentration to the set concentration.

On the other hand, at low rotation speeds and low loads, if there is not enough oxygen-rich air in the storage tank 27, the output signal of the pressure detector 28 will be at a low level, so the pumps P1 and P2 will be driven and the valve 29 will be open. All valves 18, 25, and 26 are closed, and oxygen-rich air from the oxygen enrichment device 13 is supplied to the engine 1 as part of the intake air through the valve 21. However, under normal conditions, gas leakage or tank Unless the engine 27 is damaged, the pressure of the oxygen-rich air in the tank 27 will never fall below the set value, and the engine 1 will almost never be in such an operating state.

In the illustrated embodiment, an oxygen enrichment device is activated when the engine decelerates, and the oxygen-rich air generated from the oxygen enrichment device is temporarily stored in a tank and mixed with normal air at low rotation speeds and low loads. However, it goes without saying that this is not necessarily limited to this example.

For example, in order to improve power in the output zone, oxygen-rich air may be supplied to the engine in a high load region.

Further, in the above embodiment, the opening/closing and opening angle of the valves 20, 21 are controlled by the oxygen concentration controller 22; however, as shown in FIG.
0.21 may be a solenoid valve, and ON/OFF control may be performed by an AND circuit 34 and an Ok circuit 35, which operate according to output signals from the discrimination circuit 32 and the pressure detector 28, respectively. In the figure, 33 is an inverter. In this case, the control circuit for the valve 29 and the oxygen concentration controller 22 is unnecessary.

In addition, instead of the oxygen permeable membrane, the oxygen concentration enrichment device may use a nitrogen adsorption material that adsorbs nitrogen gas to increase the oxygen concentration in the air, such as one using natural or synthetic zeolite. Needless to say, it's a good thing.

As explained above, the present invention operates the oxygen enrichment device at least when the engine decelerates, temporarily stores the oxygen-rich air obtained during deceleration, and uses it as part of the intake air depending on the engine operating state. I decided to do this, so
It has excellent effects such as reducing the energy required to operate the oxygen concentration enrichment device, and at the same time improving combustibility and improving fuel efficiency.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing one embodiment of the engine intake system of the present invention, FIG. 2 is a block diagram of its control device, and FIG. 3 is a block diagram of essential parts showing a modification thereof. ■...Engine, 4...Combustion injection nozzle, 5...
Throttle opening degree detector, 6... Rotation detector, 7...
Air flow meter, 8... Throttle valve, 10.
...Air cleaner, 13...Oxygen concentration enrichment device, 18
...Relief valve, 20, 21, 25, 26, 29...
・Valve, 27...Oxygen-rich air storage tank, 28
...Pressure detector, 24...Oxygen concentration detector.

Claims (1)

[Claims] an oxygen concentration enrichment device that increases the oxygen content ratio in the air; a storage chamber that stores the oxygen-rich air enriched by the oxygen concentration enrichment device; and when the engine decelerates, the oxygen concentration enrichment device is operated. and a control device for storing the oxygen-rich air obtained in the storage chamber in a storage chamber, and controlling the oxygen-rich air stored in the storage chamber to be supplied to the combustion chamber as necessary. intake device.