Internal Combustion Engine and Working Cycle

• US 20080092860A2
• Filed: 09/27/2005
• Published: 04/24/2008
• Est. Priority Date: 07/17/1996
• Status: Active Grant

• Current Assignee: Clyde Bryant
• Original Assignee: Clyde Bryant
• Inventors: Bryant, Clyde
• Granted Patent: US 8,215,292 B2
• Time in Patent Office: Days
• US Class Current: 123/562
• CPC Class Codes: F01L 1/053 overhead type
• CPC Class Codes: F01L 1/146 Push-rods
• CPC Class Codes: F01L 1/26 characterised by the provision of two or more valves operated simultaneously by same transmitting-gear; peculiar to machines or engines with more than two lift-valves per cylinder with coaxial valves F01L1/28
• CPC Class Codes: F01L 1/46 Component parts, details, or accessories, not provided for in preceding subgroups
• CPC Class Codes: F01L 1/465 Pneumatic arrangements
• CPC Class Codes: F01L 13/0015 for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque
• CPC Class Codes: F02B 29/0412 Multiple heat exchangers arranged in parallel or in series
• CPC Class Codes: F02B 29/0418 the intake air cooler having a bypass or multiple flow paths within the heat exchanger to vary the effective heat transfer surface
• CPC Class Codes: F02B 29/0493 Controlling the air charge temperature
• CPC Class Codes: F02B 33/06 with reciprocating-piston pumps other than simple crankcase pumps
• CPC Class Codes: F02B 33/26 Four-stroke engines characterised by having crankcase pumps
• CPC Class Codes: F02B 33/38 of Roots type
• CPC Class Codes: F02B 33/44 Passages conducting the charge from the pump to the engine inlet, e.g. reservoirs
• CPC Class Codes: F02B 37/04 Engines with exhaust drive and other drive of pumps, e.g. with exhaust-driven pump and mechanically-driven second pump
• CPC Class Codes: F02B 37/16 by bypassing charging air
• CPC Class Codes: F02B 39/10 electric
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

The invention is concerned with a method of deriving mechanical work from a combustion gas in internal combustion engines and reciprocating internal combustion engines for carrying out the method. The invention includes methods and apparatuses for managing combustion charge densities, temperatures, pressures and turbulence in order to produce a true mastery within the power cylinder in order to increase fuel economy, power, and torque while minimizing polluting emissions. In its preferred embodiments, the method includes the steps of (i) producing an air charge, (ii) controlling the temperature, density and pressure of the air charge, (iii) transferring the air charge to a power cylinder of the engine such that an air charge having a weight and density selected from a range of weight and density levels ranging from below atmospheric weight and density to heavier-than-atmospheric weight and density is introduced into the power cylinder, and (iv) then compressing the air charge at a lower-than-normal compression ratio, (v) causing a pre-determined quantity of charge-air and fuel to produce a combustible mixture, (vi) causing the mixture to be ignited within the power cylinder, and (vii) allowing the combustion gas to expand against a piston operable in the power cylinders with the expansion ratio of the power cylinders being substantially greater than the compression ratio of the power cylinders of the engine. In addition to other advantages, the invented method is capable of producing mean effective cylinder pressures ranging from lower-than-normal to higher-than-normal. In the preferred embodiments, the mean effective cylinder pressure is selectively variable (and selectively varied) throughout the mentioned range during the operation of the engine. In an alternate embodiment related to constant speed-constant load operation, the mean effective cylinder pressure is selected from the range and the engine is configured, in accordance with the present invention, such that the mean effective cylinder pressure range is limited, being varied only in the amount required for producing the power, torque and speed of the duty cycle for which the engine is designed.

Claims

86. A method of operating a four-stroke, internal combustion engine including at least one chamber with at least one intake port associated therewith, a piston partially defining said chamber and being movable in a reciprocating manner within a cylinder through a plurality of power cycles, each power cycle involving four strokes of the piston resulting from two rotations of a crankshaft and including an intake stroke, a compression stroke, an expansion stroke and an exhaust stroke, aided by combustion taking place within the chamber, said method comprising the steps of:

compressing and cooling air outside the chamber;

supplying the cooled, pressurized air to the at least one intake port associated with the chamber; and

during each cycle of the plurality of power cycles,

opening the at least one intake port,

allowing cooled, pressurized air to flow through the at least one intake port and into the chamber during at least a portion of the intake stroke,

maintaining open the at least one intake port during the portion of the intake stroke and beyond the end of the intake stroke and into the compression stroke and during a majority portion of the compression stroke,

after the maintaining step, closing the at least one intake port at a point during travel of the piston to capture in the chamber a cooled compressed charge comprising the cooled, pressurized air,

controllably delivering fuel into the chamber after the cooled compressed charge is captured within the chamber, and

igniting a fuel and air mixture within the chamber.

87. The method of claim 86, wherein said maintaining open includes operating a variable intake valve closing mechanism to keep the at least one intake port open.

88. The method of claim 86, wherein the opening step includes selectively operating at least one air intake valve, based on at least one engine condition, to open the at least one intake port.

89. The method of claim 86, wherein the step of compressing air comprises:

imparting rotational movement to a first turbine and a first compressor with exhaust air flowing from an exhaust port of the cylinder;

compressing air drawn from atmosphere with the first compressor;

compressing air received from the first compressor with a second compressor; and

supplying pressurized air from the second compressor to the intake manifold.

90. The method of claim 86 further including supplying a pressurized fuel directly to the chamber during a portion of a combustion stroke.

91. The method of claim 90, further including supplying the pressurized fuel during a portion of the compression stroke.

92. The method of claim 86, wherein said compressing includes a first stage of pressurization and a second stage of pressurization.

93. The method of claim 92, further including cooling air between said first stage of pressurization and said second stage of pressurization.

94. The method of claim 86, wherein said majority portion is greater than 90 degrees crank angle after bottom dead center.

95. The method of claim 86, wherein said step of controllably delivering fuel includes injecting a first portion of fuel a predetermined period prior to injecting a second portion of fuel.

96. The method of claim 95, wherein said injecting the second portion of fuel begins during the compression stroke and terminates during a combustion stroke.

97. The method of claim 86, including managing the pre-combustion conditions in the chamber of the engine.

98. The method of claim 86, further comprising controlling each of the characteristics of:

turbulence in the chamber;

density of the cooled, pressurized air;

pressure of the cooled, pressurized air;

temperature of the cooled, pressurized air;

mean cylinder pressure within the chamber; and

peak pressure within the chamber.

99. The method of claim 86, wherein the compressing, cooling, supplying and allowing steps include, respectively, compressing, cooling, supplying and allowing to flow a mixture of air and recirculated exhaust gas.

100. The method of claim 99, wherein said pressurizing includes subjecting the air and exhaust gas mixture to at least one stage of compression.

101. The method of claim 99, wherein said pressurizing includes subjecting the air and exhaust gas mixture to two or more stages of compression.

102. The method of claim 99, wherein said pressurizing includes subjecting the air and exhaust gas mixture to more than two stages of compression.

103. The method of claim 86, including providing, through motion of the piston, extra burn time for the combustion process.

104. The method of claim 86, further comprising the step of:

managing at least the compressing, cooling, and closing steps so as to vary power among power cycles of the plurality of power cycles.

105. The method of claim 104, further comprising the step of:

varying from one power cycle to another power cycle of the plurality of power cycles the point during travel of the piston at which the previously opened intake port is closed by the closing step.

106. The method of claim 105, wherein the varying step includes the steps of:

during one of the plurality of power cycles, closing the previously opened port when the piston is at a first point in the second half of its compression stroke; and

during another of the plurality of power cycles, closing the previously opened port when the piston is at a second point in the second half of its compression stroke, the second point being different from the first point.

107. The method of claim 86, further comprising:

controlling one or more characteristics selected from the group consisting of turbulence in the chamber, density of the cooled, pressurized air, pressure of the cooled, pressurized air, temperature of the cooled, pressurized air, mean cylinder pressure within the chamber and peak pressure within the chamber.

109. The method of claim 86, further comprising varying the pressure of the cooled, pressurized air directed during one cycle of the plurality of power cycles from the pressure of the cooled, pressurized air directed during another of the cycles of the plurality of power cycles.

113. The method of claim 86, wherein the step of controllably delivering fuel comprises the step of injecting fuel into the chamber during the compression stroke, after the at least one intake port is closed.

116. The method of claim 99, wherein the step of controllably delivering fuel comprises the step of injecting fuel into the chamber during the compression stroke, after the at least one intake port is closed.

117. The method of claim 99, including controllably introducing exhaust gas exhausted from the chamber to a flow of air and directing the resulting mixture of air and recirculated exhaust gas to at least one compressor, compressing the mixture, cooling the compressed mixture, and supplying the resulting cooled, pressurized mixture of air and recirculated exhaust gas to the at least one intake port.

118. The method of claim 117, wherein controllably introducing comprises selectively varying the proportion of exhaust gas and air in the mixture in response to at least one monitored condition.

119. The method of claim 117, further including cooling at least a portion of the exhaust gas prior to introducing the portion to the flow of air.

120. The method of claim 86, wherein the step of supplying cooled, pressurized air includes supplying the cooled, pressurized air to a manifold and supplying the cooled pressurized air from the manifold to the at least one intake port.

121. The method of claim 86, further wherein cooled, pressurized air enters the chamber through a shrouded intake valve.

122. The method of claim 88, wherein at least one intake valve is shrouded.

123. The method of claim 86, wherein the maintaining step includes maintaining the at least one intake port open for at least 65% of the compression stroke.

124. The method of claim 86, wherein the maintaining step includes maintaining the at least one intake port open for at least 70% of the compression stroke.

125. The method of claim 86, wherein the maintaining step includes maintaining the at least one intake port open for at least 80% of the compression stroke.

126. The method of claim 86, wherein the maintaining step includes maintaining the at least one intake port open for at least 85% of the compression stroke.

127. The method of claim 86, wherein the compressing step comprises compressing air through one or more stages of compression outside the chamber to a higher-than-atmospheric pressure.

128. The method of claim 127, wherein the compressing step comprises boosting the pressure of air by as much as 4 atmospheres.

129. The method of claim 127, wherein the compressing step comprises compressing air to greater than or equal to 4 atmospheres.

130. The method of claim 99, wherein the compressing step comprises compressing the air and exhaust gas mixture through one or more stages of compression outside the chamber to a higher-than-atmospheric pressure.

131. The method of claim 130, wherein the compressing step comprises boosting the pressure of the air and exhaust gas mixture by as much as 4 atmospheres.

132. The method of claim 130, wherein the compressing step comprises compressing the air and exhaust gas mixture to greater than or equal to 4 atmospheres.

139. The method of claim 86, 127, 128, 129, 130, 131, or 132, wherein the compressing and cooling step comprises cooling the pressurized air to as low as 150 degrees Fahrenheit.

140. The method of claim 139, wherein the compressing and cooling step comprises multiple stages of compression and cooling after each stage of compression.

141. The method of claim 139, wherein the maintaining step includes maintaining the at least one intake port open for at least 65% of the compression stroke.

142. The method of claim 139, wherein the maintaining step includes maintaining the at least one intake port open for at least 70% of the compression stroke.

143. The method of claim 139, wherein the maintaining step includes maintaining the at least one intake port open for at least 80% of the compression stroke.

144. The method of claim 139, wherein the maintaining step includes maintaining the at least one intake port open for at least 85% of the compression stroke.

179. The method of claim 86, wherein the maintaining step includes maintaining the at least one intake port open for at least 67% of the compression stroke.

180. The method of claim 86, 99, 123, 124, 125, 126, or 179, wherein the engine is a diesel fueled engine.

181. The method of claim 180, further comprising managing the compressing, cooling and maintaining steps such that during each power cycle of the plurality of power cycles the maximum temperature in the chamber at the end of the piston'"'"'s compression stroke and prior to combustion is less than 300 degrees Fahrenheit.

182. The method of claim 86, 99, 123, 124, 125, 126, or 179, wherein the engine is a spark ignited engine.

183. The method of claim 86, 99, 123, 124, 125, 126 or 179, where the engine is a spark-ignited gasoline fueled engine.

184. The method of claim 86, wherein the plurality of power cycles includes at least two power cycles performed during heavy load operation of the engine.

187. The method of claim 86, 99, 123, 124, 125, 126 or 179, wherein the method further comprises the step of, at every point in time during the compression stroke, maintaining the temperature in the chamber below that required to cause auto-ignition of the fuel and air mixture, until the occurrence of one of the conditions selected from the group consisting of:

(i) ignition is desired; and

(ii) sparking occurs.

188. The method of claim 86, further comprising varying the temperature of the cooled, pressurized air supplied during one cycle of the plurality of power cycles from the temperature of the cooled, pressurized air supplied during another of the cycles of the plurality of power cycles, while maintaining during each power cycle of the plurality of power cycles the temperature of the pre-compressed air, after fuel is added, less than that temperature which will cause auto-ignition of the fuel and air mixture.

189. The method of claim 86, wherein compressing and cooling air outside the chamber comprises subjecting air to multiple stages of pressurization and cooling the pressurized air at least after the last stage of pressurization outside the chamber.

190. The method of claim 86, wherein compressing and cooling air outside the chamber comprises subjecting air to multiple stages of pressurization and passing the pressurized air through a cooler after at least one stage of pressurization outside the chamber.

191. The method of claim 129, wherein the air is pre-compressed outside the chamber to at least 5 atmospheres, and then passed through at least one cooler.

192. The method of claim 132, wherein the air and exhaust gas mixture is pre-compressed outside the chamber to at least 5 atmospheres, and then passed through at least one cooler.

196. The method of claim 86, wherein the method further comprises the step of, at every point in time during the compression stroke, maintaining the temperature in the chamber below that required to cause auto-ignition of the fuel and air mixture, until the occurrence of one of the conditions selected from the group consisting of:

(i) ignition is desired; and

(it) sparking occurs, and wherein the air and fuel mixture is pre-compressed outside the chamber to at least 5 atmospheres, and then passed through at least one cooler.

197. The method of claim 182, further comprising managing the compressing, cooling and maintaining steps such that during each power cycle of the plurality of power cycles the maximum temperature in the chamber at the end of the piston'"'"'s compression stroke and prior to combustion is less than 300 degrees Fahrenheit.