CN111456847A - Miller cycle supercharged direct injection gasoline engine - Google Patents

Abstract

The invention discloses a Miller cycle supercharged direct injection gasoline engine, comprising a cylinder block, a cylinder head, a Miller cycle combustion system, a high-pressure fuel direct injection system, and a low-pressure water-cooled exhaust gas connected to the cylinder block and the cylinder head. Recirculation system, variable area exhaust gas turbocharging system, engine integrated intercooling air intake system, engine intelligent thermal management control system driven by electronic water pump, solenoid valve driven full variable displacement oil pump, controllable piston oil cooling injection system , Mid-mounted intake and exhaust continuously variable valve timing system, advanced engine fuel evaporative emission control system and efficient crankcase ventilation system. The Miller cycle combustion system in the present invention can reduce fuel consumption and improve the thermal efficiency of the engine; the variable-section exhaust gas turbocharging system cooperates with the Miller cycle combustion system to improve the intake efficiency at low speed, while taking into account the engine performance at high speed; The cooling system greatly reduces the frictional work and heat loss of the engine.

Description

Miller cycle supercharged direct injection gasoline engine

technical field

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

Background technique

"Made in China 2025—Technical Roadmap for Energy-Saving and New Energy Vehicles" requires that passenger vehicles generally implement vehicle weight reduction/miniaturization, vigorously develop hybrid power and powertrain upgrade optimization, and by 2020, compact and below will account for 55%, The proportion of hybrid power is 8%, and the thermal efficiency of gasoline engine is increased to 40%;

The energy saving of passenger vehicles is of great significance to alleviating the pressure on energy and the environment. It is particularly important to develop small-displacement engines with high energy efficiency, low fuel consumption and low emissions.

Therefore, it is necessary to design a Miller cycle supercharged direct injection gasoline engine with high energy efficiency, low fuel consumption and low emission.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the deficiencies of the prior art and provide a Miller cycle supercharged direct injection gasoline engine with high energy efficiency, low fuel consumption and low emission.

The technical solution of the present invention provides a Miller cycle supercharged direct injection gasoline engine, comprising a cylinder block, a cylinder head, a Miller cycle combustion system, a high-pressure fuel direct injection system, a low-pressure fuel injection system connected to the cylinder block and the cylinder head Water-cooled exhaust gas recirculation system, variable-section exhaust gas turbocharging system, engine integrated intercooler air intake system, engine intelligent thermal management control system driven by electronic water pump, solenoid valve-driven full variable displacement oil pump, controllable piston oil cooling Injection system, mid-mounted intake and exhaust continuously variable valve timing system, advanced engine fuel evaporative emission control system and efficient crankcase ventilation system.

Further, the Miller cycle combustion system includes a high tumble air passage, a roof ridge type combustion chamber, a shallow pit piston, a small lift and a small wrap angle intake profile, a central spark plug, and a side direct injection six-hole diamond injector. , intake and exhaust valves and exhaust ports.

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

The high-pressure oil pump is installed on the independent tile cover at the tail end of the exhaust side of the engine, and the direct injection fuel injector and the oil rail are installed on the lower side of the intake port of the engine cylinder head.

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

The exhaust gas intake port of the low-pressure water-cooled exhaust gas recirculation system is located at the rear end of the engine catalyst, the circulation control valve and the mixing valve are respectively installed on the cylinder block and the cylinder head, and the exhaust gas is sequentially cooled by the circulation cooler. After passing through the circulation control valve, it is mixed with fresh air, enters the mixing valve, is supercharged by the variable-section exhaust gas turbocharging system, and enters the intake manifold integrated intercooling position.

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

The integrated intercooler intake manifold is installed at the upper end of the cylinder head on the intake side of the engine, a water-cooled intercooler is integrated in the integrated intercooler intake manifold, and the water inlet and outlet pipes of the intercooler are connected to the The vehicle cooling system is connected;

The intercooling pipeline is located at the rear end of the engine, and is respectively connected to the outlet of the compressor of the turbocharger and the air inlet of the electronic throttle valve at the intake manifold.

Further, in the engine intelligent thermal management control system driven by the electronic water pump, the electronic water pump is installed on the cylinder block on the intake side, and is connected to the water jacket of the engine through an external hose.

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

The oil cooling nozzle is installed at the downstream position of the oil passage of the cylinder block at the lower end of the cylinder barrel, and the oil cooling nozzle control valve is installed at the upstream position of the oil passage of the cylinder block on the exhaust side of the engine. The engine control module cools the oil according to the engine operating conditions and the oil passage. The nozzle control valve is opened and closed to control the injection opening timing of the oil cooling nozzle.

Further, the mid-mounted intake and exhaust continuously variable valve timing system includes two phaser control solenoid valves, two central bolt control valves and two camshaft phase adjusters, the phaser control solenoid valves are installed in the On the camshaft cover, the camshaft phase adjuster and the central bolt control valve are installed at the front end of the camshaft;

The engine control unit determines the control command of the camshaft phase according to the camshaft position signal, the air flow signal and the throttle valve position, and the engine control unit drives the central bolt control valve to switch the oil circuit by controlling the duty cycle signal of the solenoid valve.

Further, the advanced engine fuel evaporative emission control system includes a carbon canister control valve, a carbon canister purging pump and a connecting pipeline, and the carbon canister purging pump is connected to the carbon tube control valve through the connecting pipeline, The carbon tube purging pump is located at the upper end of the intake side at the front end of the engine, the carbon canister control valve is installed on the connecting pipe at the inlet of the exhaust side supercharger, and the carbon canister purging pump is used to actively extract the carbon canister Internal fuel vapor.

Further, the forced ventilation pipeline of the high-efficiency crankcase ventilation system is located at the rear end of the top of the engine, and the three-way used is respectively connected to the resonant cavity of the vehicle air intake system, the crankcase ventilation inlet and the engine oil-gas separator outlet.

After adopting the above-mentioned technical scheme, it has the following beneficial effects:

The Miller cycle combustion system in the present invention can reduce fuel consumption and improve the thermal efficiency of the engine; the variable-section exhaust gas turbocharging system cooperates with the Miller cycle combustion system to improve the intake efficiency at low speed, while taking into account the engine performance at high speed; The cooling system greatly reduces the frictional work and heat loss of the engine.

Description of drawings

The disclosure of the present invention will become more readily understood with reference to the accompanying drawings. It should be understood that these drawings are only for the purpose of illustration and are not intended to limit the protection scope of the present invention. In the picture:

1 is a front view of a Miller cycle supercharged direct injection gasoline engine in an embodiment of the present invention;

2 is a rear view of a Miller cycle supercharged direct injection gasoline engine in an embodiment of the present invention;

3 is an intake side view of a Miller cycle supercharged direct injection gasoline engine in an embodiment of the present invention;

4 is an exhaust side view of a Miller cycle supercharged direct injection gasoline engine in an embodiment of the present invention;

5 is an exploded view of a Miller cycle supercharged direct injection gasoline engine in an embodiment of the present invention;

6 is a schematic diagram of a Miller cycle combustion system of a Miller cycle supercharged direct injection gasoline engine in an embodiment of the present invention;

7 is a schematic diagram of a low-pressure water-cooled exhaust gas recirculation system of a Miller cycle supercharged direct injection gasoline engine in an embodiment of the present invention;

8 is a schematic diagram of an engine intelligent thermal management control system driven by an electronic water pump of a Miller cycle supercharged direct injection gasoline engine according to an embodiment of the present invention;

9 is a schematic diagram of a full variable displacement oil pump lubrication system of a Miller cycle supercharged direct injection gasoline engine in an embodiment of the present invention;

10 is a schematic diagram of a high-pressure fuel direct injection system of a Miller cycle supercharged direct injection gasoline engine in an embodiment of the present invention;

11 is a schematic diagram of an engine integrated intercooled air intake system of a Miller cycle supercharged direct injection gasoline engine according to an embodiment of the present invention;

12 is a schematic diagram of a controllable piston oil cooling injection system of a Miller cycle supercharged direct injection gasoline engine in an embodiment of the present invention;

13 is a schematic diagram of a variable-section supercharging system of a Miller cycle supercharging direct-injection gasoline engine according to an embodiment of the present invention;

14 is a schematic diagram of a mid-mounted intake and exhaust continuously variable valve timing system of a Miller cycle supercharged direct injection gasoline engine according to an embodiment of the present invention;

15 is a schematic diagram of a cylinder block of a Miller cycle supercharged direct injection gasoline engine in an embodiment of the present invention;

16 is a schematic diagram of a low friction camshaft of a Miller cycle supercharged direct injection gasoline engine in an embodiment of the present invention;

17 is a schematic diagram of a roller rocker arm hydraulic tappet valve train of a Miller cycle supercharged direct injection gasoline engine in an embodiment of the present invention;

18 is a two-stage low tension timing chain system of a Miller cycle supercharged direct injection gasoline engine in an embodiment of the present invention;

19 is a schematic diagram of a cylinder head of a Miller cycle supercharged direct injection gasoline engine in an embodiment of the present invention;

20 is a schematic diagram of a cross-flow cylinder head cooling water jacket of a Miller cycle supercharged direct injection gasoline engine in an embodiment of the present invention;

21 is a schematic diagram of an advanced engine fuel evaporative emission control system for a Miller cycle supercharged direct injection gasoline engine according to an embodiment of the present invention;

22 is a schematic diagram of a high-efficiency crankcase ventilation system of a Miller cycle supercharged direct injection gasoline engine in an embodiment of the present invention;

23 is an external characteristic curve diagram of a Miller cycle supercharged direct injection gasoline engine in an embodiment of the present invention;

FIG. 24 is a general characteristic curve diagram of a Miller cycle supercharged direct injection gasoline engine in an embodiment of the present invention.

Reference number comparison table:

Miller cycle combustion system 1: high tumble air passage 101, roof ridge type combustion chamber 102, shallow pit piston 103, small lift and small wrap angle intake profile 104, center spark plug 105, side direct injection six-hole diamond-shaped fuel injection valve 106, intake and exhaust valve 107, exhaust port 108;

High pressure fuel direct injection system 2: high pressure fuel pump 21, high pressure fuel pipe 22, fuel rail 23, direct injection fuel injector 24;

Low-pressure water-cooled exhaust gas recirculation system 3: circulating cooler 31, circulation control valve 32, mixing valve 33, exhaust gas intake port 34, intake manifold 35;

Variable-section exhaust gas turbocharging system 4;

Engine intelligent thermal management control system 5: electronic water pump 51, coolant flow control valve 52;

Solenoid valve drives full variable displacement oil pump 6;

Engine integrated intercooler air intake system 7: intercooler intake manifold 71, intercooler pipeline 72, water inlet 73, water outlet 74, turbocharger compressor outlet 75, electronic throttle valve 76, pre-intercooler temperature pressure sensor 77, temperature and pressure sensor 78 after intercooling;

Controllable piston oil cooling injection system 8: oil cooling nozzle 81, oil cooling nozzle control valve 82, oil passage 83 in the cylinder;

Mid-mounted intake and exhaust continuously variable valve timing system 9: phaser control solenoid valve 91, central bolt control valve 92, camshaft phase adjuster 93;

Advanced engine fuel evaporative emission control system 10: carbon canister control valve 101, carbon canister purge pump 102, connecting pipeline 103, exhaust side supercharger inlet 104, vehicle canister pipeline 105;

High-efficiency crankcase ventilation system 11: forced ventilation pipeline 111, vehicle air intake system resonance cavity 112, crankcase ventilation inlet 113, engine oil-gas separator outlet 114, pressure sensor 115;

Cylinder block 12: water inlet 121;

Cylinder head 13: water outlet 131, independent camshaft large tile cover 132, independent camshaft small tile cover 133, high-pressure oil pump installation tile cover 134, side-mounted in-cylinder direct injection injector 135;

Full variable displacement oil pump lubrication system 14: full variable displacement oil pump 141, double oil pan 142, oil filter, oil cooler integrated module 143;

Low friction camshaft 15: high pressure oil pump driving cam 151, camshaft position signal plate 152, camshaft ball bearing 153, intake camshaft 154, ball bearing retaining ring 155;

Roller rocker arm hydraulic tappet valve train 16;

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

Detailed ways

The specific embodiments of the present invention will be further described below with reference to the accompanying drawings.

It is easy to understand that, according to the technical solutions of the present invention, without changing the essential spirit of the present invention, those of ordinary skill in the art can replace various structural modes and implementation modes with each other. Therefore, the following specific embodiments and accompanying drawings are only exemplary descriptions of the technical solutions of the present invention, and should not be regarded as all of the present invention or as limitations or restrictions on the technical solutions of the invention.

Orientation terms such as up, down, left, right, front, rear, front, back, top, bottom, etc. mentioned or possibly mentioned in this specification are defined relative to the configurations shown in the respective drawings, which are It is a relative concept, so it may change accordingly according to its different locations and different usage states. Therefore, these and other terms of orientation should not be construed as limiting.

In an embodiment of the present invention, as shown in FIGS. 1-5 , a Miller cycle supercharged direct injection gasoline engine includes a cylinder block 12 and a cylinder head 13 , and a Miller cycle combustion system 1 connected to the cylinder block 12 and the cylinder head 13 . , High-pressure fuel direct injection system 2, low-pressure water-cooled exhaust gas recirculation system 3, variable-section exhaust gas turbocharging system 4, electronic water pump driven engine intelligent thermal management control system 5, solenoid valve driven full variable displacement oil pump 6, The engine integrates an intercooled air intake system 7 , a controllable piston oil cooling injection system 8 , a mid-mounted intake and exhaust continuously variable valve timing system 9 , an advanced engine fuel evaporative emission control system 10 and a high-efficiency crankcase ventilation system 11 .

Among them, as shown in FIG. 6 , the Miller cycle combustion system 1 includes a high tumble air passage 101, a roof ridge type combustion chamber 102, a shallow pit piston 103, a small lift and small wrap angle intake profile 104, a central spark plug 105, a side Direct injection six-hole diamond injector 106 , intake and exhaust valves 107 and exhaust port 108 are installed.

Specifically, the intake profile 104 with small lift and small wrap angle is adopted. Adopting the design strategy of the air intake profile with small wrap angle can effectively form a deep Miller, greatly increase the geometric compression ratio to 12, and make full use of the expansion stroke for functional power; the design of the intake profile line 104 with small lift and small wrap angle is adopted The strategy, on the one hand, can optimize the dynamic characteristics of the cam valve system and reduce the friction loss; on the other hand, it can also increase the throttle opening and reduce the pumping loss. The small lift and small wrap angle intake profile 104 drives the opening and closing of the intake valve, and can charge an appropriate amount of fresh air into the combustion chamber.

A tangent fish-belly type high tumble air passage 101 is adopted, and the high tumble air passage 101, the back of the intake valve and the exhaust side wall surface of the combustion chamber are tangentially designed, that is, the airflow direction formed after the intake valve is opened is different from the combustion chamber. The top wall is tangent, which strengthens and guides the airflow movement of the tissue and reduces airflow loss. A high tumble baffle is arranged at the outlet of the high tumble air passage 101 near the cylinder wall to block airflow movement, so as to guide the airflow to flow to the exhaust side along the combustion chamber wall in an orderly manner, and then organize and form at the beginning of the intake stroke. High-intensity tumble airflow.

The side-mounted direct injection six-hole diamond-shaped fuel injector 106 is used, and the side-mounted direct-injection six-hole diamond-shaped fuel injector 106 is installed under the intake port. Under the guidance of the combustion chamber and the shallow-pit piston head, a suitable air-fuel mixture space distribution state can be formed in the combustion chamber in a timely manner, which is beneficial to the formation of the initial fire nucleus of the central spark plug.

Roof-shaped combustion chamber 102 with high compression ratio combined with in-cylinder high-pressure direct injection and high tumble air passage 101, cooperates with Miller cycle, improves combustion knock boundary, increases combustion rate, and can greatly improve engine fuel consumption level.

The working principle of the Miller cycle combustion system is as follows:

The fresh air enters the intake manifold through the supercharger, flows through the tangential fish-belly masking intake port, opens the intake valve with the characteristics of the small lift and small wrap angle intake profile, and cooperates with the shallow pit piston to form a high tumble flow The airflow is charged into the roof-shaped combustion chamber. The piston compresses upward and maintains a strong airflow movement. During this period, the side-mounted direct injection six-hole diamond-shaped fuel injector injects an appropriate amount of fuel in stages to form a suitable spatial distribution in the combustion chamber. Using the center spark plug to ignite, realize the ignition and combustion of the mixture, push the piston down to do work, until the exhaust valve is opened, so that the exhaust gas enters the integrated exhaust port 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 ;

The exhaust gas intake port 34 of the low-pressure water-cooled exhaust gas recirculation system 3 is located at the rear end of the engine catalyst. The circulation control valve 32 and the mixing valve 33 are respectively installed on the cylinder block 12 and the cylinder head 13. After the exhaust gas is cooled by the circulation cooler 31 in turn, After passing through the circulation control valve 32 , it is mixed with fresh air, enters the mixing valve 33 , is supercharged by the variable-section exhaust gas turbocharging system 4 , and enters the intake manifold 35 where the intercooler is integrated. The recirculating cooler 31 is installed on the exhaust side of the cylinder block, the exhaust gas recirculation control valve 32 and the mixing valve 33 are both installed on the exhaust side of the cylinder head, and the water inlet pipe of the recirculating cooler 31 is connected in series to the outlet of the vehicle heating air line , the water return pipe of the circulating cooler 31 is respectively connected to the water bottle of the whole vehicle and the water inlet pipe of the engine water pump. The low pressure exhaust gas recirculation valve behind the circulating cooler 31 is equipped with an exhaust gas temperature sensor, and the pressure difference before and after the low pressure exhaust gas recirculation valve is measured by the differential pressure sensor to accurately calculate and control the exhaust gas intake volume.

Low pressure intercooled exhaust gas recirculation system (L-EGR): It can reduce engine pumping loss, improve combustion knock boundary, reduce fuel consumption and pollutant emissions. By controlling the opening of the exhaust gas recirculation control valve, the amount of exhaust gas entering the cylinder can be controlled to reduce pumping loss, improve knocking and reduce enrichment, thereby reducing engine fuel consumption and emissions. The mixing valve makes the fresh air and exhaust gas evenly 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 block on the intake side, and is connected to the water jacket of the engine through an external hose, which can be changed according to the working conditions of the engine. Continuously adjust the total flow of cooling water, control the temperature rise of the metal wall, and reduce heat transfer loss.

The engine intelligent thermal management control system 5 can control the various components of the engine at the optimal working temperature through the cooperation of the electronic water pump 51 and the coolant flow control valve 52, mainly including the following points: 1. During the cold start stage, through the "zero" 2. Increase the temperature of the cylinder wall to improve the heat exchange of the engine and reduce the heat taken away by the coolant; 3. Through the reasonable control of the cylinder head temperature, optimize the knock boundary and optimize the combustion to reduce engine fuel consumption and emission. 4. The system can also take into account the heating/cooling needs of the engine oil cooler and the transmission oil cooler, ensuring that the engine oil and transmission oil are controlled at a suitable working temperature.

The specific implementation is as follows: the coolant of the engine is driven by the electronic water pump 51 installed on the intake side of the cylinder block, the water inlet 121 of the engine is on the cylinder block 12, and the water flowing out of the electronic water pump 51 enters the cylinder block 12 and the cylinder through this port respectively. Head 13; the coolant flow control valve 52 installed at the tail end of the cylinder head 13 controls the water outlet of the engine. The system controls the cooling water flow of the cylinder block 12 and the cylinder head 13 and controls the engine outlet water to the radiator by adjusting the opening of the internal ball valve, respectively. Air conditioning and heating, water distribution of oil cooler, so as to achieve the purpose of controlling the water temperature of cylinder block 12, cylinder head water channel and oil cooler, so as to realize rapid warm-up and reduce friction work, and control the cylinder wall temperature of cylinder block 12 to reduce heat dissipation loss , optimize fuel atomization and combustion. At the same time, at part load and high load of the engine, the water temperature of the cylinder block and cylinder head is controlled by adjusting the valve opening to avoid overheating of the engine, reduce the exhaust temperature and improve the knock boundary, and optimize the combustion to reduce the fuel consumption and emission of the engine. The cooperation of the electronic water pump and the thermal management module greatly improves the temperature adjustment capability of the cooling system, and meets the temperature requirements of the engine in different load ranges, thereby realizing the optimization of fuel consumption and emissions.

Further, as shown in FIG. 9, the Miller cycle supercharged direct injection gasoline engine also includes a full variable displacement oil pump lubrication system 14: the full variable displacement oil pump 141 can be used according to the oil pressure or oil volume of each system of the engine. It is necessary to continuously adjust the oil output pressure of the oil pump, thereby reducing the frictional power loss of the system and improving the fuel economy of the whole engine. The engine uses a double-layer oil pan 142, including an outer oil pan and a small oil pan, and the upper oil pan + the lower oil pan constitute the outer large oil pan. In the warm-up stage, only a small oil pan is used to achieve the purpose of fast warm-up. The system also uses the oil filter and oil cooler integrated module 143 to make the engine layout more compact.

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

The oil filter adopts a clip-type environmental protection filter design and is installed on the intake side of the engine block through an integrated oil passage design and oil cooler arrangement.

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

The Miller cycle supercharged direct injection gasoline engine further includes a high pressure direct fuel injection system 2 : the high pressure direct fuel injection system 2 includes a high pressure fuel pump 21 , a high pressure fuel pipe 22 , an fuel rail 23 and a direct injection fuel injector 24 . The high-pressure oil pump 21 is arranged on the independent tile cover at the rear end of the exhaust side of the engine cylinder head, the direct injection injector 24 is connected with the oil rail 23 and is integrally installed under the intake port on the intake side of the engine cylinder head. The head of 24 protrudes into the combustion chamber of the engine cylinder head. The injection pressure of the direct injection system is 35Mpa. The system can reduce the temperature of the mixture, suppress knocking, increase the compression ratio, optimize the ignition advance angle, and reduce the enrichment of the mixture, thereby effectively reducing the fuel consumption of the engine. The direct injection technology can realize quick fuel cut-off to reduce fuel consumption, and the engine does not need to build up an oil film when it resumes operation. Direct injection can increase the amount of EGR, reduce the pumping loss under low load, and improve the fuel consumption of the engine. The combination of direct injection and engine start-stop technology reduces starting fuel consumption and improves quick start performance. At the same time, the direct injection technology can realize multiple injections and retard the ignition angle, accelerate the ignition of the catalyst, reduce the emission of HC, CO, and NOx.

Further, as shown in FIG. 11 , the engine integrated intercooling air intake system 7 includes an integrated intercooling intake manifold 71 and an intercooling pipeline 72 ;

The integrated intercooled intake manifold 71 is installed at the upper end of the cylinder head on the intake side of the engine, and a water-cooled intercooler is integrated in the integrated intercooled intake manifold 71 to cool the turbocharged high-pressure and high-temperature gas, and the intermediate cold water. The water inlet 73 and the water outlet 74 of the cooler are connected to the vehicle cooling system;

The intercooling pipeline 72 is located at the rear end of the engine, and is respectively connected to the air outlet 75 of the turbocharger compressor and the air inlet of the electronic throttle valve 76 at the intercooling intake manifold 71 .

Compared with the traditional air cooling and intercooling system, the engine integrated intercooling system 7 has a higher degree of integration, so it can greatly optimize the layout space of the engine in the front cabin of the vehicle, reduce the quality of the vehicle, and reduce the fuel consumption level of the engine. The engine integrated intercooling system 7 can effectively reduce the intake air temperature of the intercooled intake manifold 71 to improve the combustion performance of the engine, thereby enhancing the performance of the engine and reducing the fuel consumption level of the engine. The integrated intercooler design adopted by this engine has a short intercooler pipeline route from the rear pressure to the intake manifold, which can effectively improve the dynamic torque response of the engine, thereby bringing a more superior vehicle acceleration response performance.

The specific implementation is: after the fresh air is supercharged by the supercharger compressor, it is connected to the electronic throttle valve 76 at the entrance of the intercooled intake manifold 71 through the intercooling pipeline 72, and then enters the intercooled intake manifold 71. , the fresh air after cooling enters into the combustion chamber of the cylinder head. The intercooler pipeline 72 and the intercooler intake manifold 71 are respectively equipped with a pre-intercooler temperature and pressure sensor 77 and a post-intercooler temperature and pressure sensor 78 to calibrate and monitor the working state of the intercooler and accurately calculate the intake air volume 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 an oil passage 83 in the cylinder;

The oil cooling nozzle 81 is installed at the downstream position of the cylinder block oil passage at the lower end of the cylinder barrel, and the oil cooling nozzle control valve 82 is installed at the upstream position of the cylinder block oil passage on the exhaust side of the engine. The engine control module controls the valve 82 according to the engine operating conditions and the oil cooling nozzle. To control the injection opening timing of the oil cooling nozzle 81, while realizing the function of suppressing knocking, the engine oil flow consumption is further reduced and the engine oil consumption is improved.

Further, as shown in FIG. 13 , the variable-section supercharging system 4 can well balance the defect of the low charging efficiency of the Miller cycle due to the high turbine end pressure output, thereby obtaining high low-end torque of the engine. Especially at low engine speeds, the requirements for the turbocharging system are very high. The variable area supercharging system 4 reduces the opening of the nozzle and reduces the turbine flow area, which is equivalent to a small volute, cancels the bleed valve, improves the efficiency, and can provide high turbine output at low engine speeds. When the engine is high speed, by increasing the nozzle opening and increasing the turbine flow, it becomes a large volute to meet the demand for large intake air volume and supercharging at high speed. The variable area supercharger system 4 is connected to the flange surface of the cylinder head integrated exhaust manifold through the flange, and is arranged in the upper middle position of the engine. The variable-section supercharger system takes into account both high-speed and low-speed engine performance, making up for the intake efficiency at low speeds of the Miller cycle. Used in conjunction with Miller cycle, the exhaust back pressure is reduced and the thermal efficiency of the engine is improved.

A specific embodiment is to control the turbo flow capacity by continuously changing the outlet angle of the nozzle ring vanes, thereby controlling the boost pressure. 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 high speed, the opening of the nozzle ring is increased, and the flow area of the turbine is increased, which is equivalent to a large A/R volute .

Further, as shown in FIG. 14 , the mid-mounted intake and exhaust continuously variable valve timing system 9 includes two phaser control solenoid valves 91 , two central bolt control valves 92 and two camshaft phase adjusters 93 . The control solenoid valve 91 is installed on the camshaft cover, and the camshaft phase adjuster 93 and the central bolt control valve 92 are installed on the front end of the camshaft;

The engine control unit determines the control command of the camshaft phase according to the camshaft position signal, the air flow signal and the throttle valve position. The engine control unit drives the central bolt control valve 92 to switch the oil circuit by controlling the duty cycle signal of the solenoid valve, so as to adjust the valve phase. The position is advanced or delayed to improve the charging efficiency, reduce the pumping loss, and improve the combustion, thereby improving the engine power, fuel economy and emission performance.

Further, as shown in Fig. 15, the Miller cycle supercharged direct injection gasoline engine also includes a cast aluminum cylinder block 12, which integrates a sprocket box structure to reduce the size of the engine. A series of installation features such as oil filter, oil cooler, mechanical water pump, starter motor, accessory system, compressor, etc., the compact structure reduces the weight of the engine and achieves the purpose of reducing the fuel consumption of the whole vehicle.

Further, as shown in Figure 16, the Miller cycle supercharged direct injection gasoline engine also includes a low-friction camshaft 15 with integrated rolling bearings, which can reduce the friction loss of the engine valve train relative to the sliding camshaft, thereby reducing engine fuel consumption, At the same time, the camshaft mechanism integrates the characteristics of the high-pressure oil pump driving cam 151 and the camshaft position signal plate 152 .

The specific implementation is as follows: the low friction camshaft 15 includes a camshaft ball bearing 153, and the camshaft ball bearing 153 is fitted into the first-speed cam bearing shell cover of the cylinder head through the interference pressure of the outer ring, and then the intake camshaft 154 is fitted with interference pressure. Into the inner ring of the ball bearing, the ball bearing retaining ring 155 is installed in the groove of the first gear camshaft cover of the cylinder head to ensure that the ball bearing will not loosen and slip out.

Further, as shown in Figure 17, the Miller cycle supercharged direct injection gasoline engine also includes a roller rocker arm hydraulic tappet valve train 16: the hydraulic tappet can be used to automatically adjust the valve clearance for lifetime maintenance-free, and the roller rocker arm and the The cam contact effectively reduces frictional work and reduces fuel consumption.

Further, as shown in Figure 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 timing chain tension in the working state. It can effectively reduce the friction loss of the chain system and improve the fuel economy of the whole engine.

The specific implementation is as follows: the system consists of a two-stage tensioner 171 , a low-friction mute chain 172 , a fixed rail 173 , a moving rail 174 , an upper guide rail 175 and a crankshaft sprocket 176 . The chain system is installed in the front-end sprocket box of the engine, wherein the two-stage tensioner 171 is installed on the front-end surface of the cylinder block. The tensioner is designed as a double plunger design which can provide low and high tension at different working loads of the chain system to reduce the friction loss of the chain system. The chain of the system is a low-friction mute chain, which is designed as a toothed chain, which can effectively reduce the working noise of the system, and at the same time can take into account the chain wear problem caused by the direct injection engine. The moving rail is made of all-plastic material, which reduces the mass of the system and contributes to the lightweight design of the engine.

Further, as shown in Figure 19, the Miller cycle supercharged direct injection gasoline engine also includes a cylinder head 13: the cylinder head 13 includes an integrated exhaust manifold, a sprocket box and other compact designs to reduce the size and weight of parts, an independent camshaft The large tile cover 132, the independent camshaft small tile cover 133, and the high-pressure oil pump installation tile cover 134 reduce the manufacturing process difficulty of the cylinder head. The side-mounted direct injection injector 135 is arranged at the lower end of the intake port, and the new Masking air port , The design of the high compression ratio combustion chamber improves the combustion efficiency and reduces the fuel consumption 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 cylinder head cooling water jacket 18 of the cylinder head enables a good coolant flow inside the cylinder head. Path and flow speed, low pressure loss, reduced temperature in the nose bridge area on the exhaust side of the cylinder head, improved knock 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 purging pump 102 and a connecting line 103 , and the carbon canister purging pump 102 is connected to the carbon canister through the connecting line 103 . The tube control valve 101, the carbon tube purge pump 102 is located at the upper end of the intake side of the front end of the engine, the carbon canister control valve 101 is installed on the connecting pipe at the inlet 104 of the exhaust side supercharger, and the carbon canister purge pump 102 is connected to the entire engine. The vehicle carbon canister pipeline 105 is used to actively extract the fuel vapor in the carbon canister.

This system is different from the traditional fuel evaporative emission control system in that its carbon canister flushing pump 102 can actively extract the fuel vapor in the carbon canister instead of relying on the pressure difference between the carbon canister and the inlet of the supercharger, so as to more efficiently prevent carbon Environmental pollution caused by the emission of fuel vapor in the tank.

Further, as shown in FIG. 22, the forced ventilation pipeline 111 of the high-efficiency crankcase ventilation system 11 is located at the rear end of the top of the engine, and the tee used is connected to the resonant cavity 112 of the vehicle air intake system, the crankcase ventilation inlet 113 and Engine oil separator outlet 114 . Compared with the traditional crankcase ventilation system, the design has a higher degree of integration. The system can effectively prevent the environmental pollution caused by the gas emission in the crankcase. At the same time, the pressure sensor 115 installed on its pipeline can effectively detect the crankcase pressure range. Used to monitor the working status of the system.

As shown in FIG. 23 , it is an external characteristic curve diagram of a Miller cycle supercharged direct injection gasoline engine in an embodiment.

The engine external characteristic curve is a curve of engine output power (torque) as a function of rotational speed measured when the engine throttle valve opening is 100%. Its two curve characteristics are: power curve and torque curve. In the external characteristic curve of the gasoline engine: the power curve has a small value at a lower speed, but it increases rapidly with the increase of the speed. After the speed increases to a certain range, the power growth rate slows down until it reaches the maximum value. The speed will continue to increase.

As shown in FIG. 24 , it is a universal characteristic curve diagram of a Miller cycle supercharged direct injection gasoline engine in an embodiment.

The universal characteristic takes the rotational speed as the abscissa and the torque or the average effective pressure as the ordinate, and draws many equal fuel consumption curves and equal power curves on the graph to form the universal characteristics of the engine.

By implementing the present invention, the external characteristics of the Miller cycle supercharged direct injection gasoline engine achieve the performance design goals:

1) Maximum liter power: 70kw

2) Maximum liter torque: 165N.m

3) Minimum specific fuel consumption: 210g/kw.h

4) Emission standard: National VI B

The Miller cycle supercharged direct injection gasoline engine has a compact structure and high thermal efficiency, which can meet the national fuel consumption regulations and emission regulations for small-displacement vehicles.

What has been described above is only the principles and preferred embodiments of the present invention. It should be pointed out that for those of ordinary skill in the art, on the basis of the principle of the present invention, several other modifications can also be made, which should also be regarded as the protection scope of the present invention.

Claims (10)

1. a Miller cycle supercharged direct injection gasoline engine, is characterized in that, comprises cylinder block, cylinder head, the Miller cycle combustion system, high pressure fuel direct injection system, low pressure connected with described cylinder block and described cylinder head Water-cooled exhaust gas recirculation system, variable-section exhaust gas turbocharging system, engine integrated intercooler air intake system, engine intelligent thermal management control system driven by electronic water pump, solenoid valve-driven full variable displacement oil pump, controllable piston oil cooling Injection system, mid-mounted intake and exhaust continuously variable valve timing system, advanced engine fuel evaporative emission control system and efficient crankcase ventilation system. 2 . The Miller cycle supercharged direct injection gasoline engine according to claim 1 , wherein the Miller cycle combustion system comprises a high tumble air passage, a roof ridge type combustion chamber, a shallow pit piston, and a small lift packet. 3 . Angular intake profile, center spark plug, side direct injection six-hole diamond injector, intake and exhaust valves and exhaust ports. 3. The Le cycle supercharged direct injection gasoline engine according to claim 1, wherein the high pressure fuel direct injection system comprises a high pressure oil pump, a direct injection fuel injector and an oil rail; The high-pressure oil pump is installed on the independent tile cover at the tail end of the exhaust side of the engine, and the direct injection fuel injector and the oil rail are installed on the lower side of the intake port of the engine cylinder head. 4. The Miller cycle supercharged direct injection gasoline engine according to claim 1, wherein the low-pressure water-cooled exhaust gas recirculation system comprises a circulating cooler, a circulating control valve and a mixing valve; The exhaust gas intake port of the low-pressure water-cooled exhaust gas recirculation system is located at the rear end of the engine catalyst, the circulation control valve and the mixing valve are respectively installed on the cylinder block and the cylinder head, and the exhaust gas is sequentially cooled by the circulation cooler. After passing through the circulation control valve, it is mixed with fresh air, enters the mixing valve, is supercharged by the variable-section exhaust gas turbocharging system, and enters the position of the intake manifold after integrated intercooling. 5. The Miller cycle supercharged direct injection gasoline engine according to claim 1, wherein the engine integrated intercooling air intake system comprises an integrated intercooling intake manifold and an intercooling pipeline; The integrated intercooler intake manifold is installed at the upper end of the cylinder head on the intake side of the engine, a water-cooled intercooler is integrated in the integrated intercooler intake manifold, and the water inlet and outlet pipes of the intercooler are connected to the The vehicle cooling system is connected; The intercooling pipeline is located at the rear end of the engine, and is respectively connected to the outlet of the compressor of the turbocharger and the air inlet of the electronic throttle valve at the intake manifold. 6. The Miller cycle supercharged direct-injection gasoline engine according to claim 1, wherein, in the engine intelligent thermal management control system driven by the electronic water pump, the electronic water pump is installed on the cylinder block on the intake side, and the external The pipe is connected to the engine water jacket. 7. The Miller cycle supercharged direct injection gasoline engine according to claim 1, wherein the controllable piston oil cooling injection system comprises an oil cooling nozzle, an oil cooling nozzle control valve and an oil passage in the cylinder; The oil cooling nozzle is installed at the downstream position of the oil passage of the cylinder block at the lower end of the cylinder barrel, and the oil cooling nozzle control valve is installed at the upstream position of the oil passage of the cylinder block at the exhaust side of the engine. The engine control module cools the oil according to the engine operating conditions and the oil passage. The nozzle control valve is opened and closed to control the injection opening timing of the oil cooling nozzle. 8 . The Miller cycle supercharged direct injection gasoline engine according to claim 1 , wherein the mid-mounted intake and exhaust continuously variable valve timing system comprises two phaser control solenoid valves, two central bolts. 9 . a control valve and two camshaft phase adjusters, the phaser control solenoid valve is installed on the camshaft cover, the camshaft phase adjuster and the central bolt control valve are installed at the front end of the camshaft; The engine control unit determines the control command of the camshaft phase according to the camshaft position signal, the air flow signal and the throttle valve position, and the engine control unit drives the central bolt control valve to switch the oil circuit by controlling the duty cycle signal of the solenoid valve. 9. The Miller cycle supercharged direct injection gasoline engine according to claim 1, wherein the advanced engine fuel evaporative emission control system comprises a carbon canister control valve, a carbon canister purge pump and a connecting pipeline, and the The carbon canister purging pump is connected to the carbon tube control valve through the connecting pipeline, the carbon tube purging pump is located at the upper end position of the intake side at the front end of the engine, and the carbon canister control valve is installed on the exhaust side supercharger On the connecting pipe at the inlet, the carbon canister flushing pump is used to actively extract the fuel vapor in the carbon canister. 10. The Miller cycle supercharged direct injection gasoline engine according to claim 1, wherein the forced ventilation pipeline of the high-efficiency crankcase ventilation system is located at the rear end position of the top of the engine, and the adopted tee is connected to the whole engine respectively. Vehicle air intake system resonant cavity, crankcase ventilation inlet and engine oil-air separator outlet.

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