JPS58158318A - Suction device for engine - Google Patents

Abstract

PURPOSE:To inhibit generation of black smoke and to improve the maximum output, by increasing an air supply quantity and a fuel supply quantity. CONSTITUTION:When a load of an engine is heavier than a predetermined value, a cool air duct 28 is opened by a switching valve 27 for a solenoid, cool air is fed into a space 31, which is inside of an enclosing component 24, by pressure from a cooling compressor 23 through the cool air duct 28. Suction air in a suction air duct 2 is cooled through a sucton air duct wall 26 and an air supply quantity is increased. Simultaneously with opening of the switching valve 28, a fuel quantity increasing device 34 is actuated and fuel increase is carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an engine blowing device capable of increasing the output of the engine.

In a diesel engine, black smoke emission concentration is one of the important factors that determines the maximum performance (maximum output) of the engine.

The amount of black smoke generated is largely related to the ratio between the amount of fuel supplied to the combustion chamber and the amount of air supplied, so-called excess air ratio. The excess air ratio decreases when the amount of fuel supplied is large, and even if the amount of fuel supplied is constant, it decreases when the amount of air supplied decreases.

Therefore, in order to increase the maximum output of a diesel engine by suppressing the generation of black smoke, both the air supply amount and the fuel supply lid need to be increased. It is an object of the present invention to provide an engine intake device which can suppress the generation of black smoke and improve maximum output by increasing both of the two.

In order to achieve this object, the engine intake system of the present invention is provided with means for cooling the outer periphery of the intake passage wall with cold air when the engine load is equal to or higher than a predetermined value.

The present invention will be described in detail with reference to the drawings.

Air taken into the air cleaner 1 is guided to the main combustion chamber 5 of the diesel engine main body 4 through an intake passage 2 and an intake valve 3. The main combustion chamber 5 is defined by a cylinder head 6, a cylinder block 7 and a piston 8 and communicates with a swirl chamber 10 via a port 9. Vortex chamber 1o
Injection nozzle 11 and glow plug 1
2 are provided. The supercharger 16 includes a turbine 17 driven by the exhaust gas flow, and a compressor 19 provided in the intake passage 2 and to which the rotation of the turbine 17 is transmitted via ll1118. Cooling compressor 2
2 generates pressurized cold air at the discharge port 23. The surrounding member (shroud) 24 surrounds the outer periphery of the intake passage wall 26 over a predetermined length up to the vicinity of the intake port 25 in the flow direction of intake air. A part of the cold air from the discharge port 23 of the cooling compressor 22 is guided to the space 31 between the inner periphery of the surrounding member 24 and the outer periphery of the intake passage wall 26 via the cold air passage 28, and is then led to the air conditioner via the return passage 30. compressor 22
be returned to. Alternatively, it may be released into the atmosphere. The electromagnetic on-off valve 27 is provided in the cold air passage 24 and
Open and close. The fuel increase device 3.1 includes an electromagnetic actuator that controls the position of a control sleeve that controls the amount of fuel discharged from the injection pump. The boost pressure sensor 35 is installed in the intake system downstream of the compressor 19 and detects the boost pressure, the rotational speed sensor 36 detects the engine rotational speed, and the load sensor 37 detects the engine load from the position of the control sleeve of the injection pump. Detect. The electronic control device 40 receives input signals from the boost pressure sensor 35, rotation speed sensor 36, and load sensor 37, and sends output signals to the electromagnetic on-off valve 27 and the fuel increase device 34.

In the supercharger 16, rich exhaust gas is transmitted from the turbine 17 to the compressor 19, so the intake air is heated when passing through the compressor 19, and the air purity of the intake air decreases, resulting in a decrease in intake efficiency. do.

In the present invention, when the engine load is a high load equal to or higher than a predetermined value, the cold air passage 28 is opened by the electromagnetic on-off valve 27, and the cold air from the cooling compressor 23 is passed through the cold air passage 28 to the inside of the surrounding member 24. It is pumped into the space 31. As a result, the intake air in the intake passage 2 is cooled through the intake passage wall 26, the density of the intake air increases, and the amount of air supplied to the combustion chamber increases. Simultaneously with the opening of the cold air passage 24 by the electromagnetic on-off valve 27, the fuel increase device 34 operates to increase the amount of fuel, so both the amount of air and fuel supplied to the combustion chamber increases, without generating black smoke. Engine power increases.

When the engine load is low, that is, less than a predetermined value, the electromagnetic on-off valve 27 closes the cold air passage 28, and the fuel increase device 3.1 is maintained in an inoperative state. Since the intake air is not cooled, it is possible to avoid deterioration in combustion efficiency and increase in cooling loss due to cooling of the intake air in the case of low loads.

In the embodiment, the operation of the cooling compressor 22 and the opening and closing of the electromagnetic on-off valve 27 are independent;
It is also possible to cool the intake air with cold air at the same time as the start of the operation. Further, although the present invention has been described with reference to an embodiment of a T-cell engine with a supercharger, the present invention can also be applied to a T-cel engine without a supercharger, and even a gasoline engine. Furthermore, although the embodiment uses cold air from a cooling compressor, it is also possible to provide a dedicated cold air generation compressor that generates cold air to cool intake air.

As described above, according to the present invention, when the engine load is high, which is equal to or higher than a predetermined value, the air density of the intake air is increased by cooling the intake air with cold air, thereby increasing the amount of air supplied to the combustion chamber. By doing so, the amount of fuel can be increased until a predetermined amount of black smoke is generated, and the engine output can be significantly increased.
can be done.

[Brief explanation of the drawing]

The drawing is a configuration diagram of an embodiment of a supercharged diesel engine to which the present invention is applied. 2...Intake passage, 1...Diesel engine body,
22... Cooling compressor, 24... Surrounding member,
26...Intake passage wall, 27...Solenoid on-off valve, 28...
-Cold air passage, 37...Load sensor, 40...Electronic control device.

Claims (1)

[Scope of Claims] ] An intake system for an engine, characterized in that means is provided for cooling the outer periphery of the intake passage wall with cold air when the engine load is equal to or higher than a predetermined value. 2. The engine intake system according to claim 1, wherein the engine is a diesel engine. 3. The engine intake system according to claim 1 or 2, wherein the engine is a supercharged engine. 1. The engine air intake system according to any one of claims 1 to 3, wherein the cold air is generated by a cooling compressor. 5. An engine intake system according to any one of claims 1 to 1, wherein the means includes a surrounding member that surrounds the outer periphery of the intake passage wall to guide cold air.