1. Field of the Invention
The present invention relates to a spark-ignition type internal combustion engine that operates with the spark-ignition type cross-cycle operation, more particularly relates to an internal combustion engine that utilizes a combination of a male-cylinder and a female-cylinder.
The present invention can be used in the field of power generation and transportation.
2. Background of the Invention
During the past twenty years, my research has focused on the power-to-weight ratio and heat-loss reduction of the compound cylinders configuration; after years of experiments, the cross-cycle operation is developed to achieve a combustion process with minimum heat loss and high power output.
This present invention is one of the possible engine configurations utilizing the cross-cycle concept, further improvements on the cross-cycle operation may be achieved in the near future; and it is my earnest wish that the information disclosed herein could make a contribution to greenhouse gas reduction and engine research.
1. The primary objective of the present invention is to provide a spark-ignition type cross-cycle internal combustion engine that is capable of the spark-ignition type cross-cycle operation; said spark-ignition type cross-cycle operation generates a long and stable power output during each expansion process, and the heat loss through the female cylinder wall is relatively lower than that of the current four-stroke engines in the same power output class.
2. The second objective of the present invention is to provide a spark-ignition type cross-cycle internal combustion engine that is capable of fast acceleration and high power output.
Table.1 demonstrates an example of the spark-ignition type cross-cycle with a piston-phase-difference of 30 degree.
Table.2 demonstrates an example of the spark-ignition type cross-cycle with a piston-phase-difference of 45 degree.
Table.3 demonstrates an example of the spark-ignition type cross-cycle with a piston-phase-difference of 60 degree.
Table.4 demonstrates an example of the spark-ignition type cross-cycle with a piston-phase-difference of 90 degree.
Table 5 demonstrates an example of the spark-ignition type cross-cycle with a piston-phase-difference of 120 degree.
The spark-ignition type cross-cycle internal combustion engine can also be abbreviated as the spark-ignition type cross-cycle engine.
The spark-ignition type cross-cycle consists of seven processes and requires at least one male-cylinder and one female-cylinder to co-act with each other; many cylinder arrangements can be employed with the present invention, however, the first embodiment will explain with the simplest cylinder arrangement, namely the Inline-type single crankshaft configuration.
The piston-phase-difference is a specific term referring to the piston position difference between the male-piston and the female-piston, and said piston-phase-difference of the cross-cycle engine can be adjusted from 30 degree to 120 degree depending on the applications and the material strength of the engine head; As a comprehensive reference, Table.1 to Table.5 are presented to demonstrate the possible alternation of the spark-ignition type cross-cycle operation with various piston-phase-difference configurations; Table.1 demonstrates the spark-ignition type cross-cycle with a piston-phase-difference of 30 degree, Table.5 demonstrates the spark-ignition type cross-cycle with a piston-phase-difference of 120 degree, wherein the smaller phase-piston-difference generally requires higher material strength, Table.2 demonstrates the spark-ignition type cross-cycle with a piston-phase-difference of 45 degree, Table.3 demonstrates the spark-ignition type cross-cycle with a piston-phase-difference of 60 degree, Table.4 demonstrates the spark-ignition type cross-cycle with a piston-phase-difference of 90 degree.
Even though a piston-phase-difference smaller than 30 degree is possible to perform the spark-ignition type cross-cycle, it is not feasible with most of the material currently available, while a piston phase difference of greater than 120 degree will increase the heat loss and impede the exhaust process of the cross-cycle.
It should be understood that the first embodiment will be using Table.3 and
The specific terminology of the spark-ignition type cross-cycle internal combustion engine will be defined as follows.
The spark-ignition type cross-cycle operation consists of seven processes, and the seven processes are named in the following order as the intake process, the cold-compression process, the injection process, the cold-expansion process, the exhaust process, the hot-compression process, the hot-expansion process.
As shown in
The coordinate-port 170 provides an air passage from the male-cylinder 101 to the female-cylinder 102, and the coordinate-valve 171 is a valve installed on the female-cylinder end of the coordinate-port 170, therefore the air pressure of the coordinate-port 170 is equal to the air pressure of the male-cylinder 101 when the coordinate-valve 171 is closed.
The female-fuel-nozzle 162 is a fuel nozzle that will directly inject the fuel into the female-cylinder 102 during the sixth process of the spark-ignition type cross-cycle operation, and said female-fuel-nozzle 162 is preferably installed on the female-cylinder section of the engine head 104 in the most cylinder arrangements; it is also possible to install said female-fuel nozzle 162 on the top section of the female cylinder wall.
The fuel used for the present invention can be gasoline, fossil-fuel, bio-fuel, natural gas, LPG, methanol, or other combination of the fuels that require a spark-plug as the ignition means.
The female-exhaust-port 198 is an exhaust port located on the lower section of the female cylinder wall, and which provides an air passage to expel the cold-expanding-medium from the female-cylinder 102 to the exhaust-manifold 199 during the exhaust process of the spark-ignition type cross-cycle operation.
Now referring from
A more detailed description of said injection process will be provided as follows; the female-cylinder 102 will ignite and expand with the hot-combusting-medium of the previous spark-ignition type cross-cycle before the injection process initiates. As the female-piston 161 moves toward BDC, the combusting pressure of the female-cylinder 102 will decrease to a point that the air pressure of the coordinate-port 170 is greater than the combusting pressure of the female-cylinder 102, at this time the injection process will be initiated by opening the coordinate-valve 171. As the injection process starts, the high-density air is injected into the female-cylinder 102 to mix with the hot-combusting-medium of the female-cylinder 102 to form a cold-expanding-medium inside the female-cylinder 102, and said cold-expanding-medium will expand at a high-density with excessive oxygen content. Generally, the coordinate-valve 171 can remain opening until the male-cylinder 101 initiates the first process of the next spark-ignition type cross-cycle, however it is preferable to shut the coordinate-valve 171 immediately after the air pressure of the coordinate-port 170 is equal to the combusting pressure of the female-cylinder 102 to prevent turbulence. During the injection process, the female-piston 161 will continue to generate power to the crankshaft 100.
The above description is the main concept of the present invention, however, the spark-ignition type cross-cycle operation is relatively complicated than four-stroke internal combustion engines, therefore, an alternative narration with crankshaft reference angle is provided as follows; it should be understood that the crankshaft reference angle described with each process is not a limitation of the process durations or the valve timings; for example, the intake process is referred to as from 0 degree to 180 degree of the crankshaft reference angle, and the cold-compression process is referred to as from 180 degree to 360 degree of the crankshaft reference angle, but the male-intake-valve can close earlier or later than 180 degree of the crankshaft reference angle to block the air passage into the male cylinder according to different applications and usages; therefore, the following narration of the crankshaft reference angle only represents as one of the many possible embodiments of the present invention; even though this following narrative embodiment is not the most ideal configuration in terms of heat-loss reduction, it can be considered as the most comprehensive description for those skilled in the art of four-stroke internal combustion engines.
The following is the narration of the first embodiment with crankshaft reference angle, wherein, Table.3 and
The spark-ignition type cross-cycle operation consists of seven processes, and the seven processes are named as the intake process, the cold-compression process, the injection process, the cold-expansion process, the exhaust process, the hot-compression process, the hot-expansion process.
For the spark-ignition type cross-cycle engine configured with the piston-phase-difference of 60 degree as in Table.3, the male-piston 151 is at TDC position at 0 degree of the crankshaft reference angle, and the male-piston 151 is at BDC position at 180 degree of the crankshaft reference angle and the male-piston 151 is at TDC position at 360 degree of the crankshaft reference angle; the female-piston 161 is at TDC position at 300 degree of the crankshaft reference angle, and the female-piston 161 is at BDC position at 480 degree of the crankshaft reference angle, and the female-piston 161 is at TDC position at 660 degree of the crankshaft reference angle.
The first process, the intake process, is to take in the air into the male-cylinder 151 from approximately 0 degree to 180 degree of the crankshaft reference angle.
The second process, the cold-compression process, is to compress the air inside the male-cylinder 101 with the male-piston 151 from approximately 180 degree to 330 degree of crankshaft reference angle.
The third process, the injection process, is to inject the high-density air of the male-cylinder 101 into the female-cylinder 102 when the combusting pressure of female-cylinder 102 is lower than the air pressure of the coordinate-port 170, thereby forming a cold-expanding-medium in the female cylinder 102; said injection process will take place from approximately 330 degree to 360 degree of the crankshaft reference angle (said injection process will initiate after the ignition in any cylinder configurations).
The fourth process, the cold-expansion process, is to generate power to the crankshaft 100 with the cold-expanding-medium while the female-piston 161 continues to move toward BDC from approximately 360 degree to 440 degree of the crankshaft reference angle (the end of cold-expansion process is depending on the position and the shape of the female-exhaust-port, 440 degree of the crankshaft reference angle is only for the demonstration purpose in this particular embodiment).
The fifth process, the exhaust process, is to expel up to 90% of the cold-expanding-medium through the female-exhaust-port 198 from approximately 440 degree to 520 degree of the crankshaft reference angle (this duration of the exhaust process is depending on the position and the shape of the female-exhaust-port 198, the actual duration of the exhaust process can vary from 60 degree to 180 degree for the different applications). The remaining portion of said cold-expanding-medium in the female-cylinder 102 will be referred as the remaining-medium after the exhaust process has completed.
The sixth process, the hot-compression process, is to compress said remaining-medium inside the female-cylinder 102 from approximately 520 degree to 660 degree of the crankshaft reference angle, and at the same time the female-fuel-nozzle 162 will inject an adequate amount of fuel to mix with the remaining-medium to prepare for ignition.
The seventh process, the hot-expansion process, is to ignite the remaining-medium with the spark-plug 163 installed in the female-cylinder, and next the hot-combusting-medium will push the female-piston 161 down to generate power from approximately 660 degree to 690 degree of the crankshaft reference angle. At approximately 690 degree of the crankshaft reference angle, the combusting pressure of the female-cylinder 102 will drop to a pressure less than the air pressure of the coordinate-port 170 (the actual timing of this moment may vary according to the intake amount of the male-cylinder and the engine load condition), at this time, the injection process of the next spark-ignition type cross-cycle operation will take over and complete the present cycle of the spark-ignition type cross-cycle operation.
Now referring from
The coordinate-valve can be constructed as a type of swing-check valves or spring-check valves, wherein the coordinate-valve will be actuated with the high-density air of the coordinate-port when the air pressure of the coordinate-port is greater than the combined force of the combusting medium of the female-cylinder and the spring tension on the coordinate-valve.
The coordinate-valve can also be constructed as an enclosed valve, wherein the spring and the valve body of the coordinate-valve are concealed inside the coordinate-port or in a concealed space with an equal pressure of the coordinate-port, thus preventing the high-density air from leaking out of the coordinate-port.
The coordinate-valve can also be actuated with a variable-timing-camshaft, so that the valve open duration and valve schedule can be adjusted to maximize the engine performance for different load conditions.
The coordinate-valve can also be a hydraulic-valve or an electromagnetic-valve. The coordinate-port can also be constructed with multiple coordinate-valves, wherein the coordinate-port can inject the high-density air into the female-cylinder at multiple spots to improve the overall performance of the injection process.
The duration of the exhaust process can range from 60 degree to 180 degree of crankshaft rotation according to the position and the shape of the female-exhaust-port. At least 10% of the cold-expansion-medium will be required to remain in the female-cylinder when the exhaust process has completed.
The duration of the injection process of the spark-ignition type cross-cycle operation can vary from 3 degree to 90 degree of crankshaft rotation for different engine operation conditions, wherein the coordinate-valve can start to open after the air pressure of the coordinate-port is higher than the combusting pressure of the female-cylinder, while the coordinate-valve can start to close after the air pressure of the coordinate-port is equal to the pressure of the female-cylinder. The duration of the injection process of the spark-ignition type cross-cycle operation can be even shortened for the low-rpm large engines, wherein the shorter duration can result in a better heat-loss-reduction.
Among all the possible configurations of the present invention, the preferable configurations are the ones that can minimize the duration of the hot-expansion process and the injection process without damaging the engine components, thereby increasing the duration of the cold-expansion process to reduce the heat loss resulted from the spark-ignition type cross-cycle operation.
The ignition of the female-cylinder can be initiated at any point between 35 degree prior to TDC position and 30 degree after TDC position with one or more spark plugs; wherein, for the configuration with multiple spark plugs, the ignition can be initiated in multiple spots inside the female-cylinder.
10% to 70% of the cold-expanding-medium will remain in said female-cylinder at the end of the exhaust process, and the duration of the exhaust process can range from 60 degree to 120 degree of crankshaft rotation; the minimum duration is from 30 degree before the BDC position of said female-piston to 30 degree after the BDC position of said female-piston, while the maximum duration is from 90 degree before the BDC position of said female-piston to 90 degree after the BDC position of said female-piston.