WO2009060976A1 - 火花点火式内燃機関 - Google Patents
火花点火式内燃機関 Download PDFInfo
- Publication number
- WO2009060976A1 WO2009060976A1 PCT/JP2008/070531 JP2008070531W WO2009060976A1 WO 2009060976 A1 WO2009060976 A1 WO 2009060976A1 JP 2008070531 W JP2008070531 W JP 2008070531W WO 2009060976 A1 WO2009060976 A1 WO 2009060976A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- compression ratio
- mechanical compression
- air
- ratio
- fuel ratio
- Prior art date
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D15/00—Varying compression ratio
- F02D15/04—Varying compression ratio by alteration of volume of compression space without changing piston stroke
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B75/00—Other engines
- F02B75/04—Engines with variable distances between pistons at top dead-centre positions and cylinder heads
- F02B75/041—Engines with variable distances between pistons at top dead-centre positions and cylinder heads by means of cylinder or cylinderhead positioning
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D13/00—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing
- F02D13/02—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing during engine operation
- F02D13/0223—Variable control of the intake valves only
- F02D13/0234—Variable control of the intake valves only changing the valve timing only
- F02D13/0238—Variable control of the intake valves only changing the valve timing only by shifting the phase, i.e. the opening periods of the valves are constant
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D13/00—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing
- F02D13/02—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing during engine operation
- F02D13/0269—Controlling the valves to perform a Miller-Atkinson cycle
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/0002—Controlling intake air
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/0002—Controlling intake air
- F02D2041/001—Controlling intake air for engines with variable valve actuation
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/0002—Controlling intake air
- F02D2041/002—Controlling intake air by simultaneous control of throttle and variable valve actuation
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/14—Introducing closed-loop corrections
- F02D41/1438—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor
- F02D41/1473—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the regulation method
- F02D41/1475—Regulating the air fuel ratio at a value other than stoichiometry
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/12—Improving ICE efficiencies
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/40—Engine management systems
Definitions
- the present invention relates to a spark ignition internal combustion engine.
- the mechanical compression ratio increases as the engine load decreases with the actual compression ratio held constant, and the intake valve closing timing is increased.
- a spark ignition type internal combustion engine which is made slow is known (see, for example, Japanese Patent Laid-Open No. 2000-0 2 1 8 5 2).
- An object of the present invention is to provide a spark ignition type internal combustion engine capable of obtaining high thermal efficiency in consideration of the fact that the air-fuel ratio at which thermal efficiency is increased differs depending on the mechanical compression ratio.
- variable compression ratio mechanism capable of changing the mechanical compression ratio and the variable valve timing mechanism capable of controlling the closing timing of the intake valve.
- the engine compression ratio is higher on the engine low load operation side than on the engine high load operation side, and on the engine high load operation side, the mechanical compression ratio is gradually decreased as the engine load increases.
- combustion with a second air-fuel ratio that is larger than the first air-fuel ratio are selectively performed, and combustion with the second air-fuel ratio is prohibited on the engine high-load operation side, and the engine low-load operation side
- a spark ignition internal combustion engine that is allowed to burn at the second air-fuel ratio.
- the first air-fuel ratio with high thermal efficiency is used on the engine high-load operation side
- the use of the second air-fuel ratio with high thermal efficiency is used on the engine low-load operation side. Allowed.
- Fig. 1 is an overall view of a spark ignition type internal combustion engine
- Fig. 2 is an exploded perspective view of a variable compression ratio mechanism
- Fig. 3 is a side sectional view of the internal combustion engine schematically shown
- Fig. 4 is a variable valve timing mechanism.
- Fig. 5 is a diagram showing the lift amount of the intake and exhaust valves
- Fig. 6 is a diagram for explaining the mechanical compression ratio, actual compression ratio, and expansion ratio
- Fig. 7 is the relationship between theoretical thermal efficiency and expansion ratio
- Fig. 8 is a diagram for explaining the normal cycle and the ultra-high expansion ratio cycle
- Fig. 9 is a diagram showing changes in the mechanical compression ratio according to the engine load
- Fig. 10 is for explaining the theoretical thermal efficiency.
- Fig. 10 is for explaining the theoretical thermal efficiency.
- Fig. 11 is a diagram for explaining the net thermal efficiency
- Fig. 12 is a diagram for explaining the difference in net thermal efficiency due to the difference in air-fuel ratio
- Fig. 13 is a flowchart for performing operation control
- Figure 14 shows a map of intake valve closing timing
- Figure 15 shows a map of intake valve closing timing
- Fig. 16 is a diagram for explaining the difference in net thermal efficiency due to the difference in maximum mechanical compression ratio
- Fig. 17 is a flow chart for performing operation control.
- Figure 1 shows a side cross-sectional view of a spark ignition internal combustion engine.
- 1 is a crankcase
- 2 is a cylinder block
- 3 is a cylinder head
- 4 is a piston
- 5 is a combustion chamber
- 6 is a spark plug arranged in the center of the top surface of the combustion chamber 5
- 7 is an intake valve
- 8 is an intake port
- 9 is an exhaust valve
- 10 is an exhaust port.
- the intake port 8 is connected to the surge tank 12 via the intake branch pipe 1 1, and each of the intake branch pipes 1 1 is a fuel injection valve for injecting fuel into the corresponding intake port 8. 1 3 is placed.
- the fuel injection valve 13 may be arranged in each combustion chamber 5 instead of being attached to each intake branch pipe 11.
- the surge tank 12 is connected to the air cleaner 15 via the intake duct 14, and in the intake duct 14, a throttle valve 17 driven by the actuate 16 and an intake using, for example, heat rays
- An air quantity detector 1 8 is arranged.
- the exhaust port 10 is connected via an exhaust manifold 19 to a catalytic converter 20 having a built-in three-way catalyst, for example, and an air-fuel ratio sensor 21 is disposed in the exhaust manifold 19.
- the piston 4 is compressed by changing the relative position of the crankcase 1 and the cylinder block 2 in the cylinder axial direction at the connecting portion between the crankcase 1 and the cylinder block 2.
- a variable compression ratio mechanism A that can change the volume of the combustion chamber 5 when it is located at the top dead center is provided, and an actual compression action start timing change mechanism B that can change the actual start time of the compression action B Is provided.
- this actual compression action start timing changing mechanism B is a variable valve timing mechanism capable of controlling the closing timing of the intake valve 7.
- the electronic control unit 30 consists of a digital computer and is connected to each other by a bidirectional bus 3 1, ROM (read only memory) 3 2, RAM (random access memory) 3 3, CPU (microphone) 3), input port 3 5 and output port 3 6
- ROM read only memory
- RAM random access memory
- CPU microphone
- crank angle sensor 42 is connected to the input port 35 to generate an output pulse every time the crankshaft rotates, for example, 30 °.
- the output port 3 6 is connected to the spark plug 6, the fuel injection valve 13, the throttle valve drive actuate 16 and the variable compression ratio mechanism A and the variable valve timing mechanism B via the corresponding drive circuit 38. Connected.
- FIG. 2 shows an exploded perspective view of the variable compression ratio mechanism A shown in FIG. 1, and FIG. 3 shows a side sectional view of the internal combustion engine schematically shown.
- a plurality of protrusions 50 spaced apart from each other are formed below both side walls of the cylinder block 2, and each of the protrusions 50 has a circular cam insertion hole. 5 1 is formed.
- a pair of camshafts 5 4 and 5 5 are provided, and each camshaft 5 4 and 5 5 is inserted into each cam insertion hole 51 so as to be rotatable.
- the circular cam 5 6 is fixed.
- These circular cams 56 are coaxial with the rotation axis of each camshaft 54, 55.
- the eccentric shaft 5 7 extends, and another circular cam 58 is eccentrically mounted on the eccentric shaft 5 7 so as to be rotatable.
- these circular cams 58 are arranged between the circular cams 56, and these circular cams 58 are rotatably inserted into the corresponding cam insertion holes 53.
- crankcase 1 and cylinder block 2 are determined by the distance between the center of circular cam 5 6 and the center of circular cam 5 8.
- the cylinder block 2 moves away from the crankcase 1 as the distance between the center of the circular cam 56 and the center of the circular cam 58 increases.
- the volume of the combustion chamber 5 increases when the piston 4 is located at the compression top dead center. Therefore, the pistons are rotated by rotating the camshafts 5 4 and 5 5. The volume of the combustion chamber 5 when the ton 4 is located at the compression top dead center can be changed.
- a pair of worm gears 6 1 and 6 2 with opposite spiral directions are provided on the rotation shafts of the drive motor 59 to rotate the cam shafts 5 4 and 5 5 in the opposite directions.
- Gears 6 3 and 6 4 meshing with the worm gears 6 1 and 6 2 are fixed to the end portions of the force shafts 5 4 and 5 5, respectively.
- the piston 4 is positioned at the compression top dead center by driving the drive motor 59.
- the volume of the combustion chamber 5 can be changed over a wide range.
- the variable compression ratio mechanism A shown in FIGS. 1 to 3 is an example, and any type of variable compression ratio mechanism can be used.
- FIG. 4 is for driving the intake valve 7 in FIG.
- variable valve timing mechanism B attached to the end of the camshaft 70 is shown.
- this variable valve timing mechanism B is composed of a timing pulley 7 1 that is rotated in the direction of the arrow by a crankshaft of the engine via a timing belt, and a cylindrical housing 7 that rotates together with the timing pulley 7 1. 2 and a rotary shaft 7 3 that rotates together with the intake valve drive cam shaft 70 and can rotate relative to the cylindrical housing 7 2, and the rotary shaft 7 3 from the inner peripheral surface of the cylindrical housing 7 2.
- a plurality of partition walls 7 4 extending to the outer peripheral surface and vanes 7 5 extending between the outer peripheral surface of the rotating shaft 7 3 to the inner peripheral surface of the cylindrical housing 7 2 between the partition walls 7 4.
- An advance hydraulic chamber 7 6 and a retard hydraulic chamber 7 7 are formed on both sides of each vane 75, respectively.
- the hydraulic oil supply control to the hydraulic chambers 7 6, 7 7 is performed by the hydraulic oil supply control valve 78.
- This hydraulic oil supply control valve 7 8 has hydraulic chambers 7 6,
- hydraulic ports 7 9, 80 hydraulic oil supply port 8 2 discharged from the hydraulic pump 8 1, a pair of drain ports 8 3, 8 4, and each port 7 9 , 8 0, 8 2, 8 3, 8 4, and a spool valve 85 for controlling the communication cutoff.
- the hydraulic oil supplied from 8 2 is supplied to the advance hydraulic chamber 76 through the hydraulic port 79 and the hydraulic oil in the retard hydraulic chamber 77 is discharged from the drain port 84.
- the rotating shaft 7 3 has a cylindrical housing. 7 Relative rotation in the direction of the arrow with respect to 2.
- variable valve timing mechanism B can be used to advance and retard the cam phase of the intake valve driving force Musshaf 0 70 by the desired amount.
- the solid line indicates the variable valve timing mechanism. B shows when cam phase of intake valve drive camshaft ⁇ 70 is most advanced, and broken line shows when cam phase of intake valve drive camshaft 70 is most retarded. Show. Therefore, the valve opening period of the intake valve 7 can be arbitrarily set between the range indicated by the solid line and the range indicated by the broken line in FIG. 5, and therefore the closing timing of the intake valve 7 is also indicated by the arrow C in FIG. Any crank angle within the range can be set.
- variable valve timing mechanism B shown in FIGS. 1 and 4 shows an example.
- the variable valve timing that can change only the closing timing of the intake valve while keeping the opening timing of the intake valve constant.
- Various types of variable valve timing mechanisms such as mechanisms can be used.
- FIG. 6 show an engine with a combustion chamber volume of 50 ml and a piston stroke volume of 50 ml for illustration purposes.
- the combustion chamber volume represents the volume of the combustion chamber when the piston is located at the compression top dead center.
- Figure 6 (A) illustrates the mechanical compression ratio.
- the mechanical compression ratio is a value that is mechanically determined from only the piston stroke volume and the combustion chamber volume during the compression stroke, and this mechanical compression ratio is expressed as (combustion chamber volume + stroke volume).
- Figure 6 (B) explains the actual compression ratio.
- Figure 6 (C) illustrates the expansion ratio.
- FIG. 7 shows the relationship between the theoretical thermal efficiency and the expansion ratio
- FIG. 8 shows a comparison between a normal cycle and an ultra-high expansion ratio cycle that are selectively used according to the load in the present invention.
- Fig. 8 (A) shows the normal cycle when the intake valve closes near the bottom dead center and the compression action is started from the piston near the bottom dead center.
- Fig. 8 (A), (A), (B) shows the normal cycle when the intake valve closes near the bottom dead center and the compression action is started from the piston near the bottom dead center.
- the combustion chamber volume is set to 5 Oml
- the stroke volume of the piston is set to 500 ml.
- the actual compression ratio is almost 1 1
- the solid line in Fig. 7 shows the change in theoretical thermal efficiency in the normal cycle when the actual compression ratio and expansion ratio are almost equal.
- the theoretical thermal efficiency increases as the expansion ratio increases, that is, as the actual compression ratio increases. Therefore, in order to increase the theoretical thermal efficiency in the normal cycle, the actual compression ratio should be increased.
- the actual compression ratio can only be increased to a maximum of about 12 due to the restriction of the occurrence of knocking during high engine load operation, and therefore the theoretical thermal efficiency must be sufficiently high in the normal cycle. I can't. ,
- the present inventor has studied to increase the theoretical thermal efficiency by strictly dividing the mechanical compression ratio and the actual compression ratio. As a result, the theoretical thermal efficiency is governed by the expansion ratio. Thus, the actual compression ratio was found to have little effect. In other words, increasing the actual compression ratio increases the explosive power, but requires a large amount of energy to compress. Therefore, even if the actual compression ratio is increased, the theoretical thermal efficiency is hardly increased.
- Fig. 8 ( ⁇ ) shows an example of using the variable compression ratio mechanism ⁇ and the variable valve timing mechanism B to increase the expansion ratio while maintaining the actual compression ratio at a low value.
- variable compression ratio mechanism A reduces the combustion chamber volume from 50 ml to 20 ml.
- variable valve timing mechanism B delays the intake valve closing timing until the actual piston stroke volume is reduced from 500 ml to 200 ml.
- the actual compression ratio is almost 11 and the expansion ratio is 11 as described above. Compared to this case, the expansion ratio is higher in the case shown in Fig. 8 (B).
- FIG. 9 shows the mechanical compression ratio, expansion ratio, intake valve 7 closing timing, actual compression ratio, intake air volume, throttle valve opening degree, and bombing loss according to the engine load at a certain engine speed. Each change is shown.
- FIG. 9 shows that the average air-fuel ratio in the combustion chamber 5 is that of the air-fuel ratio sensor 21 so that the three-way catalyst in the catalytic converter 20 can simultaneously reduce unburned HC, CO and NO x in the exhaust gas. This shows the case where feedback control is performed to the theoretical air-fuel ratio based on the output signal.
- the normal cycle shown in FIG. 8 (A) is executed during engine high load operation. Accordingly, as shown in FIG. 9, the expansion ratio is low because the mechanical compression ratio is lowered at this time, and as shown by the solid line in FIG. 9, the closing timing of the intake valve 7 is advanced as shown by the solid line in FIG. It has been. At this time, the amount of intake air is large, and at this time, the opening of the throttle valve 17 is kept fully open or almost fully open, so that the pumping loss is zero.
- the mechanical compression ratio increases as the engine load decreases, and therefore the expansion ratio increases as the engine load decreases.
- the throttle valve 17 is kept fully open or almost fully open, and therefore the amount of intake air supplied into the combustion chamber 5 does not depend on the throttle valve 17 but It is controlled by changing the valve closing timing. At this time, the bombing loss is zero.
- the mechanical compression ratio is increased as the intake air amount is decreased while the actual compression ratio is substantially constant. That is, the volume of the combustion chamber 5 when the piston 4 reaches the compression top dead center is reduced in proportion to the reduction of the intake air amount. Therefore, the volume of the combustion chamber 5 when the piston 4 reaches the compression top dead center changes in proportion to the intake air amount.
- the air-fuel ratio in the combustion chamber 5 is the stoichiometric air-fuel ratio
- the volume of the combustion chamber 5 when the piston 4 reaches the compression top dead center is equal to the fuel amount. It will change in proportion.
- the mechanical compression ratio When the engine load is further reduced, the mechanical compression ratio is further increased, and when the engine load is lowered to a medium load L, which is slightly close to the low load, the mechanical compression ratio reaches the limit mechanical compression ratio which is the structural limit of the combustion chamber 5. .
- the mechanical compression ratio When the mechanical compression ratio reaches the limit mechanical compression ratio, the mechanical compression ratio is maintained at the limit mechanical compression ratio in a region where the load is lower than the engine load L when the mechanical compression ratio reaches the limit mechanical compression ratio. Therefore, the mechanical compression ratio is maximized and the expansion ratio is maximized when the engine is under medium load operation on the low load side and during low engine load operation, that is, on the engine low load operation side. In other words, the mechanical compression ratio is maximized so that the maximum expansion ratio is obtained on the engine low load operation side.
- the engine load is lower than L.
- the closing timing of the intake valve 7 as shown by the solid line in FIG. 9 is delayed as the load becomes lower engine, the engine load decreases to the closing timing of the intake valves 7 is the combustion chamber 5 up to L 2 This is the critical valve closing timing to control the amount of intake air supplied to the valve. Closing of the intake valve 7 in the region of a load lower than the engine load L 2 when the closing timing of the intake valve 7 closing timing of the intake valve 7 is reached the limit closing timing reaches the limit closing timing The timing is held at the limit closing timing.
- the throttle valve 1 7 When the closing timing of the intake valve 7 is held at the limit closing timing, the amount of intake air can no longer be controlled depending on the change in the closing timing of the intake valve 7. In the embodiment shown in FIG. 9, at this time, that is, in a region where the load is lower than the engine load L 2 when the closing timing of the intake valve 7 reaches the limit closing timing, the throttle valve 1 7 The amount of intake air supplied to is controlled. However, if the intake air volume is controlled by the throttle valve 17, the bombing loss increases as shown in Fig. 9. On the other hand, as shown in Fig. 9, the actual compression ratio is maintained at almost the same actual compression ratio for the same engine speed at the engine load is L and the engine is operated at a higher engine load.
- the closing timing is the limit closing of the intake valve 7 as the engine load is in the lower operating range than L 2
- the actual compression ratio will be kept constant if it is kept in time.
- the solid line A shows the case where the mechanical compression ratio is increased as much as possible.
- the mechanical compression ratio A is increased, that is, when the expansion ratio is increased, at the end of the expansion stroke, that is, exhaustion.
- the air valve 9 is opened, the pressure in the combustion chamber 5 gradually decreases and finally becomes atmospheric pressure.
- the solid line C in Fig. 10 shows the change in theoretical thermal efficiency when the compressor ratio A is increased as much as possible.
- the theoretical thermal efficiency C increases as the mechanical compression ratio A increases, that is, as the expansion ratio increases, but this theoretical air-fuel ratio C begins to decrease when the point B is exceeded. That is, when the mechanical compression ratio A exceeds the point B, the pressure in the combustion chamber 5 at the end of the expansion stroke becomes equal to or higher than the atmospheric pressure, and as a result, the theoretical thermal efficiency C decreases.
- the mechanical compression ratio A does not greatly exceed the B point.
- the maximum mechanical compression ratio does not exceed the B point.
- the maximum mechanical compression ratio is the value indicated by the broken line D.
- the broken line E in Fig. 10 shows the change in the actual compression ratio when the intake air amount is controlled by changing the closing timing of the intake valve 7 when the mechanical compression ratio A reaches the maximum mechanical compression ratio D.
- the broken line F shows the change in the actual compression ratio when the intake air amount is controlled by the throttle valve 17 when the mechanical compression ratio A reaches the maximum mechanical compression ratio D.
- the broken line G shows the change in the theoretical air-fuel ratio when the intake air amount is controlled by changing the closing timing of the intake valve 7 when the mechanical compression ratio A reaches the maximum mechanical compression ratio D.
- the broken line H shows the change in the stoichiometric air-fuel ratio when the intake air amount is controlled by the throttle valve 17 when the mechanical compression ratio A reaches the maximum mechanical compression ratio D.
- Figure 11 shows the bombing loss and net thermal efficiency in addition to the theoretical thermal efficiency shown in Figure 10.
- the theoretical thermal efficiency H when the intake air amount is controlled by the throttle valve 17 is higher than the theoretical thermal efficiency G.
- the amount of intake air is controlled by the throttle valve 17, a bombing loss occurs as indicated by I in Fig. 11.
- the net heat efficiency J when the intake air amount is controlled by changing the closing timing of the intake valve 7 as shown in Fig. 11 is controlled by the throttle valve 17.
- the net thermal efficiency is higher than K.
- the control of the intake air amount is controlled by the throttle valve 1 7 from the control by the closing timing of the intake valve 7. Since the control is switched, the net thermal efficiency changes as indicated by the solid line L.
- Figure 12 shows the mechanical compression ratio when the combustion with the first air-fuel ratio and the combustion with the second air-fuel ratio larger than the first air-fuel ratio are performed, the closing timing of the intake valve 7, It shows the changes in compression ratio, theoretical thermal efficiency and net thermal efficiency.
- the first air-fuel ratio is, for example, the stoichiometric air-fuel ratio, and is indicated by a broken line in FIG. 12
- the second air-fuel ratio is, for example, a lean air-fuel ratio, and is indicated by the solid line in FIG.
- FIG. 9 shows the case where combustion with the stoichiometric air-fuel ratio is performed.Therefore, the changes in the mechanical compression ratio shown by the broken line in Fig. 11, the closing timing of the intake valve 7 and the actual compression ratio are shown in the figure. This is the same as the mechanical compression ratio indicated by the solid line in Fig. 9, the closing timing of the intake valve 7 and the actual compression ratio. It should be noted that the theoretical thermal efficiency and the net thermal efficiency when combustion with the stoichiometric air-fuel ratio is changed as shown by the broken line in FIG. 12 can be easily made from the explanation already given based on FIG. 10 and FIG. I think I can understand.
- the load on the horizontal axis represents the fuel injection amount.
- the air-fuel ratio is made the theoretical air-fuel ratio and the case where the lean air-fuel ratio is made under the same load, that is, the same fuel injection amount
- the case where the lean air-fuel ratio is made Therefore, it is necessary to increase the intake air volume compared to the case where the stoichiometric air-fuel ratio is set. Therefore, as shown in Fig. 12, under the same load, the closing timing of the intake valve 7 at the lean air-fuel ratio is the theoretical airline indicated by the broken line to increase the intake air amount as shown by the solid line. This is accelerated compared to the case of the fuel ratio.
- the engine compression ratio is equal to the stoichiometric air-fuel ratio as shown by the solid line at the lean air-fuel ratio in order to keep the actual compression ratio the same as that at the stoichiometric air-fuel ratio. It is reduced compared to the case of.
- the mechanical compression ratio is lowered, the expansion ratio is lowered, so that the theoretical thermal efficiency and the net thermal efficiency are lowered as shown by the solid line in FIG. That is, on the engine high load operation side, the net heat efficiency is higher at the stoichiometric air-fuel ratio than at the lean air-fuel ratio.
- the mechanical compression ratio when the mechanical compression ratio is maintained at the maximum mechanical compression ratio, the actual compression ratio decreases as the closing timing of the intake valve 7 is delayed.
- the mechanical compression ratio when the mechanical compression ratio is lower than the maximum mechanical compression ratio, the mechanical compression ratio changes so that the actual compression ratio becomes a constant value regardless of the stoichiometric or lean air-fuel ratio.
- the change pattern of the mechanical compression ratio at the lean air-fuel ratio is shifted to the left as compared with the change pattern of the mechanical compression ratio at the stoichiometric air-fuel ratio. Therefore, as shown in Fig.
- the engine low load operation side where the mechanical compression ratio becomes the maximum mechanical compression ratio is the same as when the actual compression ratio at the lean air-fuel ratio is the stoichiometric air-fuel ratio under the same expansion ratio. Higher than the actual compression ratio. Therefore, on the engine low load operation side, the theoretical thermal efficiency and the net thermal efficiency are higher when the lean air-fuel ratio is compared with the stoichiometric air-fuel ratio. Therefore, considering the net thermal efficiency, it is preferable to prohibit the lean air-fuel ratio, that is, the combustion with the second air-fuel ratio on the engine high-load operation side, and only the engine low-load operation side can perform the second combustion.
- combustion by the first air-fuel ratio and combustion by the second air-fuel ratio larger than the first air-fuel ratio are selectively performed, and combustion by the second air-fuel ratio is performed on the engine high load operation side. It is prohibited, and combustion by the second air-fuel ratio is permitted when the mechanical compression ratio reaches the maximum mechanical compression ratio.
- Fig. 13 shows the operation control routine for executing the first embodiment.
- step 100 it is determined whether or not the mechanical compression ratio is a load region where the maximum mechanical compression ratio is obtained under the second air-fuel ratio, that is, the lean air-fuel ratio. .
- the routine proceeds to step 101 where combustion is performed under the first air-fuel ratio, for example, the stoichiometric air-fuel ratio.
- step 102 the closing timing IC of the intake valve 7 is calculated from the map shown in FIG. 14 (A). That is, it is required when the air-fuel ratio is the stoichiometric air-fuel ratio.
- the closing timing IC of the intake valve 7 necessary for supplying the intake air amount into the combustion chamber 5 is preliminarily shown in the form of a map as shown in Fig. 14 (A) as a function of the engine load L and the engine speed N. It is stored in ROM 3 2 and the valve closing timing IC of the intake valve 7 is calculated from this map.
- the mechanical compression ratio CR is calculated.
- the opening degree of the throttle valve 17 is calculated.
- the air-fuel ratio is the stoichiometric air-fuel ratio
- the opening 0 of the throttle valve 17 is previously stored in the ROM 3 2 in the form of a map as shown in Fig. 14 (B) as a function of the engine load L and engine speed N. Is stored within.
- the variable compression ratio mechanism A is controlled so that the mechanical compression ratio becomes the mechanical compression ratio CR
- the variable valve timing mechanism B is controlled so that the closing timing of the intake valve 7 becomes the closing timing IC.
- the throttle valve 17 is controlled so that the opening degree of the throttle valve 17 becomes zero.
- step 100 when it is determined in step 100 that the mechanical compression ratio is the load region where the maximum compression ratio is obtained under the second air-fuel ratio, that is, the lean air-fuel ratio, the routine proceeds to step 105. Combustion is performed under an air-fuel ratio. That is, in step 1 0 5, the target actual compression ratio P C 'is calculated.
- step 106 the closing timing I C ′ of the intake valve 7 is calculated from the map shown in FIG. 15 (A). That is, when the air-fuel ratio is a lean air-fuel ratio, the closing timing IC ′ of the intake valve 7 necessary to supply the required intake air amount into the combustion chamber 5 is a function of the engine load L and the engine speed N as shown in FIG. 5 (A) is stored in advance in the ROM 32 in the form of a map as shown in FIG. 5, and the closing timing IC ′ of the intake valve 7 is calculated from this map.
- the mechanical compression ratio CR ′ is calculated.
- the opening of the throttle valve 17 is calculated.
- the opening 0 'of the throttle valve 1 7 is the engine load PGi / JP ⁇ U (en / 070531
- step 1 0 As a function of L and engine speed N, it is stored in advance in R O M 3 2 in the form of a map as shown in FIG. 15 (B). Then step 1 0
- variable valve timing mechanism B is controlled so that the closing timing of the intake valve 7 becomes the closing timing IC ′, and the throttle valve 17 is opened so that the opening degree becomes ⁇ ′.
- Tor valve 1 7 is controlled.
- Fig. 12 shows changes in the mechanical compression ratio when the engine speed is relatively low.
- Fig. 16 shows changes in the mechanical compression ratio, theoretical thermal efficiency, and net thermal efficiency at high engine speeds.
- the broken line indicates the first air-fuel ratio, for example, the stoichiometric air-fuel ratio
- the solid line indicates the second air-fuel ratio, that is, the lean air-fuel ratio. Yes.
- the maximum mechanical compression ratio is a predetermined reference value CR.
- the combustion is performed with the second air-fuel ratio, that is, the lean air-fuel ratio, and the maximum mechanical compression ratio is a predetermined reference value CR.
- the mechanical compression ratio reaches the maximum mechanical compression ratio, combustion is performed at the first air-fuel ratio, for example, the stoichiometric air-fuel ratio.
- Fig. 17 shows the operation control routine for executing the second embodiment.
- step 200 it is determined whether or not the mechanical compression ratio is a load region where the maximum mechanical compression ratio is obtained under the second air-fuel ratio, that is, the lean air-fuel ratio. . If the mechanical compression ratio is not in the load range where the maximum compression ratio is reached, proceed to step 20 1 and go to the first air-fuel ratio.
- combustion is performed under a theoretical air-fuel ratio
- step 201 the target actual compression ratio PC is calculated.
- step 202 the closing timing I C of the intake valve 7 is calculated from the map shown in FIG. 14 (A).
- step 2 0 3 the mechanical compression ratio C
- step 204 the opening ⁇ of the throttle valve 17 is calculated from the top shown in FIG. 14 (B).
- step 210 the variable compression ratio mechanism A is controlled so that the mechanical compression ratio becomes the mechanical compression ratio CR, and the variable valve timing mechanism B so that the closing timing of the intake valve 7 becomes the closing timing IC. Is controlled, and the throttle valve 17 is controlled so that the opening degree of the throttle valve 17 becomes zero.
- step 200 the mechanical compression ratio becomes the second air-fuel ratio.
- the routine proceeds to step 205 and the maximum mechanical compression ratio C R m a
- step 206 the target actual compression ratio P C 'is calculated.
- step 20 07 the closing timing I C ′ of the intake valve 7 is calculated from the map shown in FIG. 15 (A).
- step 208 the mechanical compression ratio C R 'is calculated.
- step 2009 the opening degree 0 'of the throttle valve 17 is calculated from the map shown in FIG. 15 (B).
- step 2 1 the variable compression ratio mechanism A is controlled so that the mechanical compression ratio becomes the mechanical compression ratio CR ′, and the variable valve timing mechanism so that the closing timing of the intake valve 7 becomes the closing timing IC ′.
- B is controlled, and the throttle valve 17 is controlled so that the opening degree of the throttle valve 17 becomes 0 ′.
- variable compression ratio mechanism ⁇ is formed so that the expansion ratio becomes 20 or more.
- the intake air amount can be controlled without depending on the throttle valve 17 by increasing the closing timing of the intake valve 7 as the engine load decreases. Accordingly, in the embodiment according to the present invention, when the solid line and the broken line in FIG. 9 are both included, in the embodiment according to the present invention, the engine load becomes low when the intake valve 7 is closed. As a result, it is moved in a direction away from the intake bottom dead center BDC until the limit valve closing timing L 2 where the amount of intake air supplied into the combustion chamber can be controlled.
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Output Control And Ontrol Of Special Type Engine (AREA)
- Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
- Combined Controls Of Internal Combustion Engines (AREA)
Abstract
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
BRPI0816100A BRPI0816100B1 (pt) | 2007-11-06 | 2008-11-05 | motor de combustão interna do tipo de ignição por centelha |
US12/672,186 US8276554B2 (en) | 2007-11-06 | 2008-11-05 | Spark ignition type internal combustion engine |
CN2008801062084A CN101802371B (zh) | 2007-11-06 | 2008-11-05 | 火花点火式内燃机 |
DE112008003249T DE112008003249B4 (de) | 2007-11-06 | 2008-11-05 | Fremdgezündete Brennkraftmaschine |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2007-288541 | 2007-11-06 | ||
JP2007288541A JP4367547B2 (ja) | 2007-11-06 | 2007-11-06 | 火花点火式内燃機関 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2009060976A1 true WO2009060976A1 (ja) | 2009-05-14 |
Family
ID=40625858
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2008/070531 WO2009060976A1 (ja) | 2007-11-06 | 2008-11-05 | 火花点火式内燃機関 |
Country Status (7)
Country | Link |
---|---|
US (1) | US8276554B2 (ja) |
JP (1) | JP4367547B2 (ja) |
CN (1) | CN101802371B (ja) |
BR (1) | BRPI0816100B1 (ja) |
DE (1) | DE112008003249B4 (ja) |
RU (1) | RU2434154C1 (ja) |
WO (1) | WO2009060976A1 (ja) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP5942805B2 (ja) * | 2012-11-16 | 2016-06-29 | トヨタ自動車株式会社 | 火花点火式内燃機関 |
US9194344B1 (en) * | 2014-05-28 | 2015-11-24 | Electro-Motive Diesel, Inc. | Dual fuel engine having selective compression reduction |
CN106285985A (zh) * | 2016-09-30 | 2017-01-04 | 广州汽车集团股份有限公司 | 汽油发动机过量空气系数燃烧控制方法及燃烧控制系统 |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2007071046A (ja) * | 2005-09-05 | 2007-03-22 | Toyota Motor Corp | 可変圧縮比機構を備えた内燃機関 |
JP2007239550A (ja) * | 2006-03-07 | 2007-09-20 | Nissan Motor Co Ltd | 圧縮比可変エンジン |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP4345307B2 (ja) * | 2003-01-15 | 2009-10-14 | トヨタ自動車株式会社 | 可変圧縮比機構を備えた内燃機関の制御装置 |
-
2007
- 2007-11-06 JP JP2007288541A patent/JP4367547B2/ja not_active Expired - Fee Related
-
2008
- 2008-11-05 CN CN2008801062084A patent/CN101802371B/zh not_active Expired - Fee Related
- 2008-11-05 US US12/672,186 patent/US8276554B2/en active Active
- 2008-11-05 BR BRPI0816100A patent/BRPI0816100B1/pt not_active IP Right Cessation
- 2008-11-05 WO PCT/JP2008/070531 patent/WO2009060976A1/ja active Application Filing
- 2008-11-05 DE DE112008003249T patent/DE112008003249B4/de not_active Expired - Fee Related
- 2008-11-05 RU RU2010107213/06A patent/RU2434154C1/ru active
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2007071046A (ja) * | 2005-09-05 | 2007-03-22 | Toyota Motor Corp | 可変圧縮比機構を備えた内燃機関 |
JP2007239550A (ja) * | 2006-03-07 | 2007-09-20 | Nissan Motor Co Ltd | 圧縮比可変エンジン |
Also Published As
Publication number | Publication date |
---|---|
BRPI0816100B1 (pt) | 2019-12-17 |
JP2009114949A (ja) | 2009-05-28 |
DE112008003249B4 (de) | 2012-03-01 |
BRPI0816100A2 (pt) | 2015-08-25 |
DE112008003249T5 (de) | 2010-09-16 |
CN101802371A (zh) | 2010-08-11 |
JP4367547B2 (ja) | 2009-11-18 |
RU2434154C1 (ru) | 2011-11-20 |
CN101802371B (zh) | 2013-03-13 |
US8276554B2 (en) | 2012-10-02 |
RU2010107213A (ru) | 2011-09-10 |
US20100282215A1 (en) | 2010-11-11 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP4259545B2 (ja) | 火花点火式内燃機関 | |
JP4450024B2 (ja) | 火花点火式内燃機関 | |
JP4428442B2 (ja) | 火花点火式内燃機関 | |
JP2007303423A (ja) | 火花点火式内燃機関 | |
JP4259569B2 (ja) | 火花点火式内燃機関 | |
JP4450025B2 (ja) | 火花点火式内燃機関 | |
JP4367549B2 (ja) | 火花点火式内燃機関 | |
JP4367550B2 (ja) | 火花点火式内燃機関 | |
JP4631848B2 (ja) | 火花点火式内燃機関 | |
JP4367551B2 (ja) | 火花点火式内燃機関 | |
JP4367548B2 (ja) | 火花点火式内燃機関 | |
JP4835457B2 (ja) | 内燃機関 | |
JP4450026B2 (ja) | 火花点火式内燃機関 | |
JPWO2010146719A1 (ja) | 火花点火式内燃機関 | |
JP2009008016A (ja) | 火花点火式内燃機関 | |
JP5088448B1 (ja) | 火花点火内燃機関 | |
JP4367547B2 (ja) | 火花点火式内燃機関 | |
JP4930337B2 (ja) | 火花点火式内燃機関 | |
JP4911144B2 (ja) | 火花点火式内燃機関 | |
JP4420105B2 (ja) | 火花点火式内燃機関 | |
JP5429136B2 (ja) | 火花点火内燃機関 | |
JP2013113191A (ja) | 火花点火内燃機関 | |
JP2011117418A (ja) | 火花点火式内燃機関 | |
JP2010024856A (ja) | 火花点火式内燃機関 | |
JP2012097660A (ja) | 可変圧縮比機構を備える内燃機関 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 200880106208.4 Country of ref document: CN |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 08848063 Country of ref document: EP Kind code of ref document: A1 |
|
DPE1 | Request for preliminary examination filed after expiration of 19th month from priority date (pct application filed from 20040101) | ||
WWE | Wipo information: entry into national phase |
Ref document number: 12672186 Country of ref document: US |
|
WWE | Wipo information: entry into national phase |
Ref document number: 890/DELNP/2010 Country of ref document: IN |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2010107213 Country of ref document: RU |
|
WWE | Wipo information: entry into national phase |
Ref document number: 1120080032491 Country of ref document: DE |
|
RET | De translation (de og part 6b) |
Ref document number: 112008003249 Country of ref document: DE Date of ref document: 20100916 Kind code of ref document: P |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 08848063 Country of ref document: EP Kind code of ref document: A1 |
|
REG | Reference to national code |
Ref country code: DE Ref legal event code: 8607 |
|
ENP | Entry into the national phase |
Ref document number: PI0816100 Country of ref document: BR Kind code of ref document: A2 Effective date: 20100225 |