CN111456847A

CN111456847A - Miller cycle supercharging direct injection gasoline engine

Info

Publication number: CN111456847A
Application number: CN202010426423.5A
Authority: CN
Inventors: 王立新; 尹建民; 吴楚; 郑巍; 张秀英; 顾洁; 郎伟钦; 邱劲草; 靳宝宏; 付文峰; 谢薇; 开进彬; 郑有能; 王和国; 黄彬; 陈凯; 刘杰; 李晶; 朱玉萍; 刘兵
Original assignee: SAIC General Motors Corp Ltd; Pan Asia Technical Automotive Center Co Ltd
Current assignee: SAIC General Motors Corp Ltd; Pan Asia Technical Automotive Center Co Ltd
Priority date: 2020-05-19
Filing date: 2020-05-19
Publication date: 2020-07-28

Abstract

The invention discloses a Miller circulating supercharging direct-injection gasoline engine which comprises a cylinder body, a cylinder cover, a Miller circulating combustion system, a high-pressure fuel direct-injection system, a low-pressure water-cooling waste gas recirculation system, a variable-section waste gas turbocharging system, an engine integrated intercooling air inlet system, an electronic water pump driven engine intelligent thermal management control system, a solenoid valve driven full-variable displacement oil pump, a controllable piston engine oil cooling injection system, a central intake and exhaust continuous variable valve timing system, an advanced engine fuel evaporation and discharge control system and a high-efficiency crankcase ventilation system, wherein the Miller circulating combustion system, the high-pressure fuel direct-injection system, the low-pressure water. The Miller cycle combustion system can reduce fuel consumption and improve the heat efficiency of the engine; the variable-section exhaust gas turbocharging system is matched with the Miller circulating combustion system to improve the air intake efficiency at low speed, and simultaneously the engine performance at high speed is considered; the cooling system driven by the electronic water pump greatly reduces the friction work and the heat loss of the engine.

Description

Miller cycle supercharging direct injection gasoline engine

Technical Field

The invention relates to the technical field of engines, in particular to a Miller cycle supercharging direct injection gasoline engine.

Background

China manufactures 2025-energy-saving and new energy automobile technical route map requires that a passenger car generally executes vehicle light weight/miniaturization, and hybrid power and power assembly upgrading optimization are vigorously developed, and by 2020, the compact type and the proportion below 55 percent, the hybrid power proportion 8 percent and the thermal efficiency of a gasoline engine are improved to 40 percent;

the energy conservation of the passenger car has great significance for reducing energy and environmental stress. The development of a small-displacement engine with high energy efficiency, low oil consumption and low emission is particularly important.

Therefore, there is a need for a miller cycle supercharged direct injection gasoline engine with high energy efficiency, low fuel consumption and low emissions.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide the Miller cycle supercharging direct injection gasoline engine with high energy efficiency, low oil consumption and low emission.

The technical scheme of the invention provides a Miller circulating supercharged direct-injection gasoline engine which comprises a cylinder body, a cylinder cover, a Miller circulating combustion system, a high-pressure fuel direct-injection system, a low-pressure water-cooling waste gas recirculation system, a variable-section waste gas turbocharging system, an engine integrated intercooling air inlet system, an engine intelligent heat management control system driven by an electronic water pump, a solenoid valve driven full-variable displacement oil pump, a controllable piston engine oil cooling injection system, a central intake and exhaust continuous variable valve timing system, an advanced engine fuel evaporation and discharge control system and a high-efficiency crankcase ventilation system, wherein the Miller circulating combustion system, the high-pressure fuel direct-injection system, the.

Further, the Miller cycle combustion system comprises a high-tumble air passage, a ridge-shaped combustion chamber, a shallow-pit type piston, a small-lift small-packet-angle air inlet molded line, a middle spark plug, a side-mounted direct-injection six-hole diamond-shaped oil injector, an air inlet/outlet valve and an exhaust passage.

Further, the high-pressure fuel direct injection system comprises a high-pressure oil pump, a direct injection injector and an oil rail;

the high-pressure oil pump is arranged on an independent tile cover at the tail end of the exhaust side of the engine, and the direct-injection oil injector and the oil rail are arranged on the lower side of an air inlet channel of a cylinder cover of the engine.

Further, the low-pressure water-cooled exhaust gas recirculation system comprises a circulation cooler, a circulation control valve and a mixing valve;

the exhaust gas intake of the low-pressure water-cooling exhaust gas recirculation system is located at the rear end of an engine catalyst, the circulation control valve and the mixing valve are respectively installed on a cylinder body and a cylinder cover, and exhaust gas is sequentially cooled by the circulation cooler and then mixed with fresh air after passing through the circulation control valve to enter the mixing valve and then enters the integrated intercooling rear position of the intake manifold after being supercharged by the variable-section exhaust gas turbocharging system.

Further, the engine integrated intercooling intake system comprises an integrated intercooling intake manifold and an intercooling pipeline;

the integrated intercooling intake manifold is arranged at the upper end position of a cylinder cover at the air inlet side of the engine, a water-cooling intercooler is integrated in the integrated intercooling intake manifold, and a water inlet pipeline and a water outlet pipeline of the intercooling water cooler are connected with a whole vehicle cooling system;

the intercooling pipeline is positioned at the rear end of the engine and is respectively connected with an outlet of a compressor of the turbocharger and an air inlet of an electronic throttle valve at an air inlet manifold.

Furthermore, in the engine intelligent thermal management control system driven by the electronic water pump, the electronic water pump is mounted on the cylinder body on the air inlet side and is connected with the engine water jacket through an external hose.

Further, the controllable piston engine oil cooling injection system comprises an engine oil cooling nozzle, an engine oil cooling nozzle control valve and an oil passage in the cylinder body;

the engine oil cooling nozzle is arranged at the downstream position of an oil duct of a cylinder body at the lower end of the cylinder barrel, the engine oil cooling nozzle control valve is arranged at the upstream position of the oil duct of the cylinder body at the exhaust side of the engine, and the engine control module controls the injection opening time of the engine oil cooling nozzle according to the operation condition of the engine and the opening and closing of the engine oil cooling nozzle control valve.

Further, the central intake and exhaust continuously variable valve timing system comprises two phaser control solenoid valves, two central bolt control valves and two camshaft phase adjusters, wherein the phaser control solenoid valves are mounted on a camshaft cover, and the camshaft phase adjusters and the central bolt control valves are mounted at the front ends of camshafts;

the engine control unit determines a control instruction of a camshaft phase according to a camshaft position signal, an air flow signal and a throttle position, and drives the central bolt control valve to switch an oil way by controlling a duty ratio signal of an electromagnetic valve.

Further, advanced engine fuel evaporation emission control system includes carbon tank control valve, carbon tank purge pump and connecting line, the carbon tank purge pump passes through connecting line is connected to the carbon pipe control valve, the carbon pipe purge pump is located engine front end side upper end position of admitting air, the carbon tank control valve is installed on the connecting pipe of exhaust side booster entrance, the carbon tank purge pump is used for initiatively extracting carbon tank internal combustion oil steam.

Furthermore, a forced ventilation pipeline of the high-efficiency crankcase ventilation system is positioned at the rear end of the top of the engine, and a tee joint is adopted to be respectively connected with a resonant cavity of a whole vehicle air intake system, a crankcase ventilation inlet and an outlet of an oil-gas separator of the engine.

After adopting above-mentioned technical scheme, have following beneficial effect:

the Miller cycle combustion system can reduce fuel consumption and improve the heat efficiency of the engine; the variable-section exhaust gas turbocharging system is matched with the Miller circulating combustion system to improve the air intake efficiency at low speed, and simultaneously the engine performance at high speed is considered; the cooling system driven by the electronic water pump greatly reduces the friction work and the heat loss of the engine.

Drawings

The disclosure of the present invention will become more readily understood by reference to the drawings. It should be understood that: these drawings are for illustrative purposes only and are not intended to limit the scope of the present disclosure. In the figure:

FIG. 1 is a front view of a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the present invention;

FIG. 2 is a rear view of a Miller cycle boosted direct injection gasoline engine in accordance with one embodiment of the present invention;

FIG. 3 is an intake side view of a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the present invention;

FIG. 4 is an exhaust side view of a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the present invention;

FIG. 5 is an exploded view of a Miller cycle boosted direct injection gasoline engine in accordance with one embodiment of the present invention;

FIG. 6 is a schematic diagram of a Miller cycle combustion system of a Miller cycle boosted direct injection gasoline engine according to one embodiment of the present invention;

FIG. 7 is a schematic diagram of a low pressure water cooled exhaust gas recirculation system for a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the present invention;

FIG. 8 is a schematic diagram of an electronic water pump driven engine intelligent thermal management control system for a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the present invention;

FIG. 9 is a schematic diagram of a full variable displacement oil pump lubrication system for a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the present invention;

FIG. 10 is a schematic illustration of a high pressure direct fuel injection system for a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the present invention;

FIG. 11 is a schematic illustration of an engine integrated intercooler intake system for a Miller cycle boosted direct injection gasoline engine, in accordance with an embodiment of the present invention;

FIG. 12 is a schematic diagram of a controllable piston oil cooling injection system for a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the present invention;

FIG. 13 is a schematic illustration of a variable area boosting system for a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the present invention;

FIG. 14 is a schematic diagram of a mid-mount intake and exhaust continuously variable valve timing system for a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the present invention;

FIG. 15 is a schematic illustration of a cylinder block of a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the present invention;

FIG. 16 is a schematic illustration of a low friction camshaft of a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the present invention;

FIG. 17 is a schematic illustration of a roller rocker arm hydraulic tappet valvetrain of a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the present invention;

FIG. 18 is a two-stage low tension timing chain system for a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the present invention;

FIG. 19 is a schematic illustration of a cylinder head of a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the present invention;

FIG. 20 is a schematic illustration of a cross-flow cylinder head cooling jacket for a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the present invention;

FIG. 21 is a schematic diagram of an advanced engine evaporative emissions control system for a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the present invention;

FIG. 22 is a schematic representation of a highly efficient crankcase ventilation system for a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the invention;

FIG. 23 is a graph of the external characteristics of a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the present invention;

FIG. 24 is a graphical representation of the universal characteristic of a Miller cycle boosted direct injection gasoline engine in accordance with an embodiment of the present invention.

Reference symbol comparison table:

miller cycle combustion system 1: the device comprises a high-tumble air passage 101, a ridge-shaped combustion chamber 102, a shallow pit type piston 103, a small-lift small-wrap-angle air inlet molded line 104, a middle spark plug 105, a side-mounted direct-injection six-hole diamond-shaped oil injector 106, an air inlet/outlet valve 107 and an exhaust passage 108;

high-pressure direct fuel injection system 2: a high-pressure oil pump 21, a high-pressure oil pipe 22, an oil rail 23 and a direct injection injector 24;

a low-pressure water-cooling exhaust gas recirculation system 3, comprising a circulating cooler 31, a circulating control valve 32, a mixing valve 33, an exhaust gas inlet 34 and an intake manifold 35;

a variable-section exhaust gas turbocharger system 4;

the engine intelligent thermal management control system 5: an electronic water pump 51 and a coolant flow control valve 52;

the electromagnetic valve drives the full-variable displacement oil pump 6;

the engine integrated intercooling intake system 7: the system comprises an intercooling air inlet manifold 71, an intercooling pipeline 72, a water inlet 73, a water outlet 74, a turbocharger compressor air outlet 75, an electronic throttle valve 76, an intercooling front temperature pressure sensor 77 and an intercooling rear temperature pressure sensor 78;

controllable piston engine oil cooling injection system 8: an oil cooling nozzle 81, an oil cooling nozzle control valve 82, and a cylinder block oil passage 83;

the mid-type intake and exhaust continuously variable valve timing system 9: a phaser control solenoid valve 91, a center bolt control valve 92, a camshaft phase adjuster 93;

advanced engine fuel evaporative emissions control system 10: a carbon tank control valve 101, a carbon tank purge pump 102, a connecting pipeline 103, an exhaust side supercharger inlet 104 and a whole vehicle carbon tank pipeline 105;

high-efficiency crankcase ventilation system 11: a forced ventilation pipeline 111, a finished automobile air intake system resonant cavity 112, a crankcase ventilation inlet 113, an engine oil-gas separator outlet 114 and a pressure sensor 115;

the cylinder body 12: a water inlet 121;

a cylinder cover 13: a water outlet 131, an independent camshaft large bush cover 132, an independent camshaft small bush cover 133, a high-pressure oil pump mounting bush cover 134 and a side-mounted in-cylinder direct injection oil injector 135;

full variable displacement oil pump lubrication system 14: a full variable displacement oil pump 141, a double-layer oil pan 142, an oil filter, and an oil cooler integration module 143;

low-friction camshaft 15: a high-pressure oil pump driving cam 151, a camshaft position signal disc 152, a camshaft ball bearing 153, an air inlet camshaft 154 and a ball bearing retainer ring 155;

a roller rocker arm hydraulic tappet valve train 16;

two-stage low tension timing chain system 17: two-stage tensioner 171, low friction silent chain 172, fixed rail 173, movable rail 174, upper guide rail 175, crankshaft sprocket 176.

Detailed Description

The following further describes embodiments of the present invention with reference to the accompanying drawings.

It is easily understood that according to the technical solution of the present invention, those skilled in the art can substitute various structures and implementation manners without changing the spirit of the present invention. Therefore, the following detailed description and the accompanying drawings are merely illustrative of the technical aspects of the present invention, and should not be construed as limiting or restricting the technical aspects of the present invention.

The terms of orientation of up, down, left, right, front, back, top, bottom, and the like referred to or may be referred to in this specification are defined relative to the configuration shown in the drawings, and are relative terms, and thus may be changed correspondingly according to the position and the use state of the device. Therefore, these and other directional terms should not be construed as limiting terms.

In an embodiment of the invention, as shown in fig. 1-5, the miller cycle supercharging direct injection gasoline engine comprises a cylinder body 12 and a cylinder cover 13, a miller cycle combustion system 1 connected with the cylinder body 12 and the cylinder cover 13, a high-pressure fuel direct injection system 2, a low-pressure water-cooled exhaust gas recirculation system 3, a variable cross-section exhaust gas turbocharging system 4, an electronic water pump driven engine intelligent thermal management control system 5, an electromagnetic valve driven full-variable displacement oil pump 6, an engine integrated intercooling air intake system 7, a controllable piston engine oil cooling injection system 8, a central intake and exhaust continuous variable valve timing system 9, an advanced engine fuel evaporation and emission control system 10 and a high-efficiency crankcase ventilation system 11.

As shown in fig. 6, the miller cycle combustion system 1 includes a high tumble air passage 101, a ridge-type combustion chamber 102, a shallow pit type piston 103, a small-lift small-wrap-angle air intake profile 104, a middle spark plug 105, a side-mounted direct-injection six-hole diamond injector 106, an air intake and exhaust valve 107, and an exhaust passage 108.

Specifically, a small lift and small pocket angle air intake profile 104 is used. By adopting a design strategy of a small-wrap-angle air inlet molded line, a deep Miller (Miller) can be effectively formed, the geometric compression ratio is greatly improved to 12, and the work-doing capacity of an expansion stroke is fully utilized; by adopting a design strategy of the small-lift small-wrap-angle air inlet molded line 104, on one hand, the dynamic characteristic of a cam valve system can be optimized, and the friction loss is reduced; on the other hand, the opening of a throttle valve can be increased, and the pumping loss can be reduced. The small-lift small-wrap-angle air inlet molded line 104 drives the opening and closing of an air inlet valve, and a proper amount of fresh air can be filled into a combustion chamber.

The tangential fish belly type high tumble air passage 101 is adopted, the high tumble air passage 101, the back of the intake valve and the exhaust side wall surface of the combustion chamber are in tangential transition design, namely the air flow direction formed after the intake valve is opened is tangential to the wall surface at the top of the combustion chamber, the effect of strengthening and guiding the movement of the organization air flow is achieved, and the air flow loss is reduced. The outlet of the high tumble air passage 101 is provided with a high tumble baffle feature near one side of the cylinder wall for blocking the air flow movement, so that the air flow is guided to flow to the exhaust side along the wall surface of the combustion chamber in order, and then the high-intensity tumble air flow is formed in the early stage of the intake stroke.

The side-mounted direct-injection six-hole diamond-shaped oil injector 106 is adopted, the side-mounted direct-injection six-hole diamond-shaped oil injector 106 is installed below an air inlet channel, oil bundles of the direct-injection six holes are in a diamond shape, and under the guidance of a high tumble air passage, a ridge-shaped combustion chamber and a shallow-pit piston head, a proper mixed gas space distribution state can be formed in the combustion chamber in time, so that the initial fire core formation of the middle-mounted spark plug is facilitated.

The high compression ratio ridge type combustion chamber 102 is combined with the in-cylinder high-pressure direct injection and high tumble air passage 101 and matched with the Miller cycle, so that the combustion detonation boundary is improved, the combustion rate is increased, and the oil consumption level of an engine can be greatly improved.

The operating principle of the miller cycle combustion system is as follows:

fresh air enters an air inlet manifold through a supercharger, flows through a tangential fishbelly type masking air inlet channel, opens an air inlet valve with small lift and small included angle air inlet molded line characteristics, forms high tumble flow by matching with a shallow pit type piston, and is filled in a ridge type combustion chamber. The piston is compressed to move upwards, so that strong airflow movement is maintained, and during the period, the side-positioned direct-injection six-hole rhombus-shaped oil injector injects proper amount of fuel oil in a plurality of times, so that a proper space distribution state is formed in the combustion chamber. The middle spark plug is used for ignition, so that ignition and combustion of mixed gas are realized, the piston is pushed to move downwards to do work until the exhaust valve is opened, and waste gas enters the integrated exhaust passage and flows out of the combustion chamber.

Further, as shown in fig. 7, the low-pressure water-cooled exhaust gas recirculation system 3 includes a circulation cooler 31, a circulation control valve 32, and a mixing valve 33;

an exhaust gas intake port 34 of the low-pressure water-cooling exhaust gas recirculation system 3 is positioned at the rear end position of an engine catalyst, a circulation control valve 32 and a mixing valve 33 are respectively installed on a cylinder body 12 and a cylinder cover 13, exhaust gas is sequentially cooled by a circulation cooler 31, then mixed with fresh air after passing through the circulation control valve 32, enters the mixing valve 33, is pressurized by a variable-section exhaust gas turbocharging system 4, and then enters an integrated intercooling position of an intake manifold 35. The circulating cooler 31 is installed on the exhaust side of the cylinder body, the exhaust gas recirculation control valve 32 and the mixing valve 33 are installed on the exhaust side of the cylinder cover, the water inlet pipe of the circulating cooler 31 is connected in series to the outlet of a warm air pipeline of the whole vehicle, and the water return pipe of the circulating cooler 31 is connected to the water inlet pipe of a kettle of the whole vehicle and the water inlet pipe of an engine water pump respectively. An exhaust gas temperature sensor is arranged in front of the low-pressure exhaust gas recirculation valve behind the circulating cooler 31, and the pressure difference between the front and the rear of the low-pressure exhaust gas recirculation valve is measured through a pressure difference sensor so as to accurately calculate and control the air inflow of the exhaust gas.

The low-pressure intercooling exhaust gas recirculation system (L-EGR) can reduce the pumping loss of an engine, improve the combustion detonation boundary and reduce the oil consumption and pollutant emission, and the opening degree of an exhaust gas recirculation control valve is controlled to control the amount of exhaust gas entering a cylinder so as to achieve the purposes of reducing the pumping loss, improving the detonation and reducing the enrichment, thereby reducing the oil consumption and the emission of the engine, and a mixing valve enables fresh air and the exhaust gas to be uniformly mixed.

Further, as shown in fig. 8, in the engine intelligent thermal management control system 5 driven by the electronic water pump, the electronic water pump 51 is installed on the cylinder body on the air inlet side and connected with the engine water jacket through an external hose, so that the total flow of cooling water can be continuously adjusted according to the working condition change of the engine, the temperature rise of the metal wall surface is controlled, and the heat exchange loss is reduced.

The intelligent thermal management control system 5 of the engine can control each component of the engine at the optimal working temperature through the mutual matching of the electronic water pump 51 and the coolant flow control valve 52, and mainly comprises the following points: 1. the quick warm-up is realized through zero flow in the cold starting stage; 2. the temperature of the wall surface of the cylinder body is increased, the heat exchange of the engine is improved, and the heat taken away by the cooling liquid is reduced; 3. through reasonable control of the temperature of a cylinder cover, a detonation boundary is optimized, and combustion is optimized, so that the oil consumption and the emission of an engine are reduced. 4. The system can also give consideration to the heating/cooling requirements of the engine oil cooler and the gearbox oil cooler, and ensures that the engine oil and the gearbox oil are controlled at proper working temperatures.

The specific implementation scheme is as follows: the engine coolant is driven by an electronic water pump 51 arranged on the air inlet side of the cylinder body, a water inlet 121 of the engine is arranged on the cylinder body 12, and water flowing out of the electronic water pump 51 enters the cylinder body 12 and the cylinder cover 13 through the water inlet; the cooling liquid flow control valve 52 arranged at the tail end of the cylinder cover 13 controls the water outlet of the engine, the system respectively controls the cooling water flow of the cylinder body 12 and the cylinder cover 13 and controls the water outlet of the engine to a radiator, air-conditioning warm air and oil cooler water distribution by adjusting the opening of the internal ball valve, thereby achieving the purpose of controlling the water temperatures of the cylinder body 12, a cylinder cover water channel and an oil cooler, realizing the purposes of quickly warming and reducing friction work, controlling the temperature of the cylinder wall surface of the cylinder body 12 to reduce heat dissipation loss and optimizing fuel atomization and combustion. Meanwhile, the water temperature of a cylinder body and a cylinder cover is controlled by adjusting the opening of a valve at partial load and high load of the engine, so that the overheating of the engine is avoided, the exhaust temperature is reduced, the detonation boundary is improved, and the combustion is optimized, so that the oil consumption and the emission of the engine are reduced. The cooperation of the electronic water pump and the heat management module greatly improves the temperature regulation capacity of the cooling system and meets the temperature requirements of the engine in different load intervals, so that the optimization of oil consumption and emission is realized.

Further, as shown in fig. 9, the miller cycle boosted direct injection gasoline engine further includes a full variable displacement oil pump lubrication system 14: the full-variable displacement oil pump 141 can continuously adjust the oil output pressure of the oil pump according to the oil pressure or oil quantity requirement of each system of the engine, thereby reducing the friction power loss of the system and improving the fuel economy of the whole engine. This engine has used double-deck oil pan 142, including outer oil bottom shell and little oil pan, goes up the oil bottom shell + and constitutes outer big oil bottom shell down the oil pan. In the warming-up stage, only a small oil pan is used, and the purpose of quickly warming up is achieved. The system also employs an oil filter and oil cooler integration module 143 to make the engine more compact.

The specific implementation scheme is as follows: the full-variable displacement oil pump 141 is arranged on the upper oil pan and is driven by an oil pump chain wheel, an oil pump chain and a crankshaft chain wheel; the engine ECM controls the oil pump oil pressure proportional control valve to realize closed-loop control of the engine oil pressure. The double-layer oil pan 142 is an embedded small oil pan in the outer-layer large oil pan, and switching of engine oil in the inner oil pan and circulation of the outer oil pan is realized through the switch of the control valve arranged in the inner oil pan.

The oil filter adopts a cartridge clip type environment-friendly oil filter design and is arranged and installed on the air inlet side of the engine cylinder body through an integrated oil duct design and an oil cooler.

Further, as shown in fig. 10, the high-pressure direct fuel injection system 2 can improve the combustion efficiency, and reduce the fuel consumption and the pollutant emission.

The miller cycle supercharged direct injection gasoline engine further comprises a high-pressure direct fuel injection system 2: the high-pressure direct fuel injection system 2 includes a high-pressure oil pump 21, a high-pressure oil pipe 22, an oil rail 23, and a direct fuel injector 24. The high-pressure oil pump 21 is arranged on an independent tile cover at the rear end of the exhaust side of an engine cylinder cover, the direct-injection oil injector 24 and the oil rail 23 are connected into a whole and are installed below an air inlet side air inlet channel of the engine cylinder cover, and the head of the direct-injection oil injector 24 extends into a combustion chamber of the engine cylinder cover. The injection pressure of the direct injection system is 35Mpa, the system can reduce the temperature of mixed gas, inhibit detonation, improve the compression ratio, optimize the ignition advance angle and reduce the enrichment of the mixed gas, thereby effectively reducing the oil consumption of the engine. The direct injection technology can realize quick fuel cut-off and oil consumption reduction, and an oil film is not required to be established when the engine is recovered to run. The direct injection can improve the EGR amount, reduce the pumping loss under low load and improve the oil consumption of the engine. The combination of direct injection and engine start-stop technologies can reduce the starting oil consumption and improve the quick starting performance. Meanwhile, the direct injection technology can realize multiple injection and ignition angle delay, accelerate the ignition of the catalyst, reduce the emission of HC, CO and NOx, realize better direct injection atomization, reduce enrichment and improve the emission of HC during starting and warming.

Further, as shown in fig. 11, the engine integrated intercooler intake system 7 includes an integrated intercooler intake manifold 71 and an intercooler pipe 72;

the integrated intercooling intake manifold 71 is arranged at the upper end position of a cylinder cover at the air inlet side of the engine, a water-cooled intercooler is integrated in the integrated intercooling intake manifold 71 and used for cooling high-pressure and high-temperature gas after turbocharging, and a water inlet 73 and a water outlet 74 of the intercooling water cooler are connected with a cooling system of the whole vehicle;

the intercooling pipeline 72 is positioned at the rear end of the engine and is respectively connected with an air outlet 75 of a turbocharger compressor and an air inlet of an electronic throttle valve 76 at the intercooling air inlet manifold 71.

Compared with the traditional air cooling intercooling system, the integrated engine intercooling system 7 has higher integration level, so that the arrangement space of the engine in the front cabin of the whole vehicle can be greatly optimized, the mass of the whole vehicle is reduced, and the oil consumption level of the engine is reduced. The engine integrated intercooling system 7 can effectively reduce the intake air temperature of the intercooling intake manifold 71 to improve the combustion performance of the engine, so that the performance of the engine is improved, and the oil consumption level of the engine is reduced. The engine adopts an integrated intercooling design, and has a short line from the pressurized intercooling pipeline to the intake manifold, so that the dynamic torque response of the engine can be effectively improved, and the better acceleration response performance of the whole vehicle is brought.

The specific implementation scheme is as follows: after being pressurized by a supercharger compressor, the fresh air is connected to an electronic throttle valve 76 at the inlet of an intercooling air inlet manifold 71 through an intercooling pipeline 72, then enters the intercooling air inlet manifold 71, and enters a cylinder head combustion chamber after being cooled. The intercooling pipeline 72 and the intercooling intake manifold 71 are respectively provided with an intercooling front temperature and pressure sensor 77 and an intercooling rear temperature and pressure sensor 78 for calibrating and monitoring the working state of the intercooler and accurately calculating the intake air quantity of the engine.

Further, as shown in fig. 12, the controllable piston oil-cooling injection system 8 includes an oil-cooling nozzle 81, an oil-cooling nozzle control valve 82, and a cylinder block oil passage 83;

the engine oil cooling nozzle 81 is arranged at the downstream position of a cylinder body oil passage at the lower end of a cylinder barrel, the engine oil cooling nozzle control valve 82 is arranged at the upstream position of the cylinder body oil passage at the exhaust side of an engine, and the engine control module controls the injection opening time of the engine oil cooling nozzle 81 according to the operation condition of the engine and the opening and closing of the engine oil cooling nozzle control valve 82, so that the knocking function is suppressed, the oil flow consumption of the engine is further reduced, and the oil consumption of the engine is improved.

Further, as shown in fig. 13, the variable area supercharging system 4 can well balance the defect of low charging efficiency of the miller cycle due to high vortex end pressure output, so as to obtain high low end torque of the engine. Especially at low engine speeds, very high demands are placed on the turbocharging system. The variable cross-section supercharging system 4 reduces the turbine flow area by reducing the opening of the nozzle, is equivalent to a small volute, cancels a gas release valve, improves the efficiency, and can provide high vortex end output when the engine is at low speed. When the engine is at a high speed, the opening of the nozzle is increased, the flow of the turbine is increased, and the turbine becomes a large volute, so that the requirement of large air inflow and pressurization at the high speed is met. The variable-section supercharger system 4 is connected with the flange surface of the integrated exhaust manifold of the cylinder cover through a flange and is arranged at the middle upper position of the engine. The variable-section supercharger system has the advantages that the performance of the high-speed and low-speed engine is taken into consideration simultaneously, and the air inlet efficiency of the Miller cycle at low speed is well compensated. The engine is matched with Miller for cycle use, simultaneously reduces exhaust back pressure and improves the thermal efficiency of the engine.

A particular embodiment is to control the boost pressure by controlling the turbine flow capacity by continuously varying the exit angle of the nozzle ring vanes. When the engine is at low speed, the opening of the nozzle ring is reduced, and the flow area of the turbine is reduced, which is equivalent to a small A/R volute; when the engine is at a high speed, the opening of the nozzle ring is increased, the flow area of the turbine is increased, and the engine is equivalent to a large A/R volute.

Further, as shown in fig. 14, the central intake-exhaust continuously variable valve timing system 9 includes two phaser control solenoid valves 91, two center bolt control valves 92, and two camshaft phase adjusters 93, the phaser control solenoid valves 91 being mounted on the camshaft cover, the camshaft phase adjusters 93 and the center bolt control valves 92 being mounted at the front ends of the camshafts;

the engine control unit determines a control instruction of the camshaft phase according to the camshaft position signal, the air flow signal and the throttle position, and drives the central bolt control valve 92 to perform oil circuit switching by controlling the solenoid valve duty ratio signal, so that the gas distribution phase is adjusted to be advanced or delayed, the inflation efficiency is improved, the pumping loss is reduced, the combustion is improved, and the engine dynamic property, the fuel economy and the emission performance are improved.

Further, as shown in fig. 15, the miller cycle supercharging direct injection gasoline engine further comprises a cast aluminum cylinder body 12, which integrates a chain wheel box structure, reduces the size of the engine, avoids a T-shaped sealing structure, integrates a series of installation features such as an oil filter, an oil cooler, a mechanical water pump, a starting motor, an accessory system, a compressor and the like, has a compact structure, reduces the weight of the engine, and achieves the purpose of reducing the oil consumption of the whole vehicle.

Further, as shown in fig. 16, the miller cycle supercharged direct injection gasoline engine further comprises a low friction camshaft 15 integrated with a rolling bearing, so that friction loss of an engine valve mechanism can be reduced relative to a sliding camshaft, and therefore fuel consumption of the engine is reduced, and meanwhile, the camshaft mechanism integrates the features of a high pressure oil pump driving cam 151 and a camshaft position signal disc 152.

The specific implementation scheme is as follows: the low-friction camshaft 15 comprises a camshaft ball bearing 153, the camshaft ball bearing 153 is pressed into a first-gear camshaft bush cover of the cylinder cover through outer ring interference, then an air inlet camshaft 154 is pressed into a ball bearing inner ring through interference, and a ball bearing retainer ring 155 is arranged in a clamping groove of the first-gear camshaft bush cover of the cylinder cover to ensure that the ball bearing cannot be loosened and slide out.

Further, as shown in fig. 17, the miller cycle supercharged direct injection gasoline engine further includes a roller rocker arm hydraulic tappet valve train 16: the hydraulic tappet can automatically adjust the valve clearance without maintenance throughout the life, and the roller rocker arm is contacted with the cam to effectively reduce friction work and reduce oil consumption.

Further, as shown in fig. 18, the miller cycle supercharged direct injection gasoline engine further includes a two-stage low-tension timing chain system 17: the two-stage low-tension timing chain system can effectively reduce the force of the plunger of the timing chain tensioner acting on the timing chain system in a working state, thereby effectively reducing the friction loss of the chain system and improving the fuel economy of the whole engine.

The specific implementation scheme is as follows: the system consists of a two-stage tensioner 171, a low friction silent chain 172, a fixed rail 173, a movable rail 174, an upper guide rail 175 and a crankshaft sprocket 176. The chain system is mounted in the engine front end sprocket box with the two-stage tensioner 171 mounted on the cylinder front face. The tensioner is designed to be a dual plunger design that provides low and high two-stage tension at different operating loads of the chain system to reduce friction losses of the chain system. The chain of the system is a low-friction silent chain, and the chain is designed as a toothed chain, so that the working noise of the system can be effectively reduced, and the problem of chain abrasion caused by the requirement of a direct injection engine can be solved. The movable rail is made of all plastic materials, so that the quality of the system is reduced, and the lightweight design of the engine is facilitated.

Further, as shown in fig. 19, the miller cycle supercharged direct injection gasoline engine further includes a cylinder head 13: the cylinder cover 13 comprises an integrated exhaust manifold, the size and the weight of parts are reduced through compact design such as a chain wheel box, the process difficulty of cylinder cover manufacturing is reduced through the independent camshaft large tile cover 132, the independent camshaft small tile cover 133 and the high-pressure oil pump mounting tile cover 134, the side-arranged in-cylinder direct injection oil injector 135 is arranged at the lower end of an air inlet channel, and the novel Masking air passage and high compression ratio combustion chamber design improves the combustion efficiency and fuel consumption reduction level.

Further, as shown in fig. 20, the miller cycle supercharged direct injection gasoline engine further includes a cross-flow cylinder head cooling water jacket 18: the cross-flow type cylinder cover cooling water jacket 18 of the cylinder cover enables the interior of the cylinder cover to have a good cooling liquid flow path and flow speed, low pressure loss, reduced temperature of a nose bridge area at the exhaust side of the cylinder cover and improved detonation boundary.

Further, as shown in fig. 21, the advanced engine fuel evaporative emission control system 10 includes a carbon canister control valve 101, a carbon canister purge pump 102 and a connecting pipeline 103, wherein the carbon canister purge pump 102 is connected to the carbon canister control valve 101 through the connecting pipeline 103, the carbon canister purge pump 102 is located at an upper end of an air inlet side of the front end of the engine, the carbon canister control valve 101 is installed on a connecting pipe at an inlet 104 of a supercharger at an exhaust side, and the carbon canister purge pump 102 is connected to a whole vehicle carbon canister pipeline 105 for actively pumping fuel vapor in the carbon canister.

The system is different from the traditional fuel evaporation emission control system in that the carbon tank purge pump 102 can actively pump fuel vapor in the carbon tank without depending on the pressure difference between the carbon tank and the inlet of the supercharger, so that the problem of environmental pollution caused by the fuel vapor emission in the carbon tank can be more effectively prevented.

Further, as shown in fig. 22, the forced ventilation pipe 111 of the high-efficiency crankcase ventilation system 11 is located at the rear end position of the top of the engine, and is connected with the vehicle air intake system resonant cavity 112, the crankcase ventilation inlet 113 and the engine air separator outlet 114 by three-way joints. Compared with the traditional crankcase ventilation system, the system has higher design integration degree, can effectively prevent the environmental pollution problem caused by the gas emission in the crankcase, and can effectively detect the pressure range of the crankcase by the pressure sensor 115 arranged on the pipeline of the system so as to monitor the working state of the system.

Fig. 23 is a graph showing the external characteristics of a miller cycle supercharged direct-injection gasoline engine in one embodiment.

The engine external characteristic curve is a curve of the measured engine output power (torque) with the rotation speed when the engine throttle opening is 100%. The two curves are characterized by a power curve and a torque curve respectively. In the gasoline engine external characteristic curve: the power curve has a small value at a low rotating speed, but rapidly increases along with the increase of the rotating speed, after the rotating speed is increased to a certain interval, the power increasing speed is slowed down until the maximum value, and the rotating speed continues to increase.

Fig. 24 shows a characteristic diagram of a miller cycle supercharged direct-injection gasoline engine according to an embodiment.

The universal characteristic is that the rotating speed is used as an abscissa, the torque or the average effective pressure is used as an ordinate, and a plurality of equal fuel consumption curves and equal power curves are drawn on a graph to form the universal characteristic of the engine.

By implementing the invention, the external characteristics of the Miller cycle supercharged direct injection gasoline engine reach the performance design target:

1) maximum power per liter: 70kw

2) Maximum torque-up: 165N.m

3) Minimum specific oil consumption of 210g/kw.h

4) Emission standard: guoliu B

The Miller cycle supercharging direct injection gasoline engine has compact structure and high thermal efficiency, and can meet the national requirements of oil consumption regulations and emission regulations on small displacement vehicles.

The foregoing is considered as illustrative only of the principles and preferred embodiments of the invention. It should be noted that, for those skilled in the art, several other modifications can be made on the basis of the principle of the present invention, and the protection scope of the present invention should be regarded.

Claims

1. The Miller circulating supercharged direct-injection gasoline engine is characterized by comprising a cylinder body, a cylinder cover, a Miller circulating combustion system, a high-pressure fuel direct-injection system, a low-pressure water-cooling waste gas recirculation system, a variable-section waste gas turbocharging system, an engine integrated intercooling air inlet system, an electronic water pump driven engine intelligent thermal management control system, a solenoid valve driven full-variable displacement oil pump, a controllable piston engine oil cooling and injection system, a central intake and exhaust continuous variable valve timing system, an advanced engine fuel evaporation and discharge control system and a high-efficiency crankcase ventilation system, wherein the Miller circulating combustion system, the high-pressure fuel direct-injection system, the low-pressure water.

2. The miller-cycle, boosted, direct-injection gasoline engine of claim 1, wherein the miller-cycle combustion system comprises a high-tumble air passage, a roof-shaped combustion chamber, a shallow-pit piston, a small-lift small-packet-angle intake profile, a center-mounted spark plug, a side-mounted direct-injection six-hole rhombus injector, an intake valve, an exhaust valve, and an exhaust passage.

3. The le-cycle boosted direct injection gasoline engine of claim 1, wherein the high pressure direct fuel injection system comprises a high pressure oil pump, a direct injection injector, and an oil rail;

4. The miller cycle, boosted, direct injection gasoline engine of claim 1, wherein the low-pressure, water-cooled exhaust gas recirculation system includes a recirculation cooler, a recirculation control valve, and a mixing valve;

5. The miller-cycle, boosted, direct-injection gasoline engine of claim 1, wherein the engine integrated intercooled intake system comprises an integrated intercooled intake manifold and an intercooled line;

6. The Miller cycle supercharged direct-injection gasoline engine of claim 1, wherein the electronic water pump driven engine intelligent thermal management control system is characterized in that the electronic water pump is mounted on the air inlet side cylinder body and is connected with the engine water jacket through an external hose.

7. The miller-cycle, boosted, direct-injection gasoline engine of claim 1, wherein the controllable-piston oil-cooling injection system includes an oil-cooling injector, an oil-cooling injector control valve, and a cylinder block oil gallery;

8. The miller-cycle, boosted, direct-injection gasoline engine of claim 1, wherein the mid-range, intake and exhaust, continuously variable valve timing system comprises two phaser control solenoid valves mounted on a camshaft cover, two center bolt control valves mounted on a camshaft nose, and two camshaft phase adjusters;

9. The miller-cycle, boosted, direct-injection gasoline engine of claim 1, wherein the advanced engine fuel evaporative emissions control system comprises a canister control valve, a canister purge pump, and a connecting line, the canister purge pump being connected to the canister control valve via the connecting line, the canister purge pump being located at an upper end of an intake side of the engine front end, the canister control valve being mounted on the connecting line at an inlet of the exhaust side supercharger, the canister purge pump being configured to actively draw fuel vapor from the canister.

10. The miller-cycle supercharged direct-injection gasoline engine of claim 1, wherein the forced ventilation pipeline of the high-efficiency crankcase ventilation system is located at the rear end of the top of the engine and is provided with a tee joint which is respectively connected with a resonance cavity of a whole vehicle air intake system, a crankcase ventilation inlet and an outlet of an oil-gas separator of the engine.