Internal combustion engine and working cycle

• US 20060021606A1
• Filed: 09/27/2005
• Published: 02/02/2006
• Est. Priority Date: 07/17/1996
• Status: Active Grant

• Current Assignee: Clyde C Bryant
• Original Assignee: Clyde C Bryant
• Inventors: Bryant, Clyde C.
• 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

1. A method of operating a four-stroke internal combustion engine including at least one cylinder and a piston slidable in the cylinder and moving through a plurality of power cycles each involving an intake stroke, a compression stroke, an expansion stroke and an exhaust stroke, the method comprising:

supplying pressurized air from an intake manifold to at least one air intake port of a chamber in the cylinder;

selectively operating at least one air intake valve to open at least one air intake port to allow pressurized air to flow between the chamber and the intake manifold substantially during a majority portion of a compression stroke of the piston; and

operably controlling a fuel supply system to inject fuel into the chamber after the at least one intake valve is closed.

2. The method of claim 1, wherein the pressurized air is cooled before being supplied to the air intake port.

3. The method of claim 2, wherein said selectively operating includes operating a variable intake valve closing mechanism to keep at least one intake valve open.

4. The method of claim 2, wherein the variable intake valve closing mechanism is operated electronically.

5. The method of claim 2, wherein the selective operation of at least one air intake valve is based on at least one engine condition.

6. The method of claim 2, wherein said selectively operating includes operating an intake valve to remain open for a portion of a second half of the compression stroke of the piston.

7. The method of claim 2, wherein said operably controlling a fuel supply system includes operating a fuel injector assembly electronically.

8. The method of claim 1, wherein selectively operating includes selectively operating at least one valve to open a single intake port.

9. The method of claim 1, further comprising, at or after an intake valve is closed, selectively operating at least one intake valve to open at least one intake port through which additional pressurized air is injected into the chamber.

10. The method of claim 1, further comprising:

imparting rotational movement to a first turbine and a first compressor of a first turbocharger 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.

11. The method of claim 10, wherein fuel is injected during a combustion stroke.

12. The method of claim 11, wherein fuel injection begins during the compression stroke.

13. The method of claim 10, wherein said selectively operating includes operating a variable intake valve closing mechanism to interrupt cyclical movement of at least one intake valve.

14. The method of claim 10, wherein the selective operation of at least one air intake valve is based on at least one engine condition.

15. The method of claim 10, wherein said selectively operating includes operating at least one air intake valve to remain open for a portion of a second half of the compression stroke of the piston.

16. The method of claim 10, wherein said controllably operating a fuel supply system includes operating a fuel injector assembly electronically.

17. The method of claim 10, wherein the air is cooled prior to supplying it to the at least one air intake port.

18. The method of claim 10, wherein at or after a first intake valve is closed a secondary charge of pressurized air is injected into the chamber.

19. The method of claim 18, wherein at least part of the secondary charge is injected through the first air intake port.

20. The method of claim 18, wherein at least a part of the secondary charge is injected through a second air intake port.

21. The method of claim 18, wherein the secondary charge is cooled prior to injection.

22. The method of claim 1, further including pressurizing air and supplying said air to the intake manifold of the engine.

23. The method of claim 22 wherein said selectively operating includes maintaining fluid communication between the chamber and the intake manifold during a portion of an intake stroke and through at least a majority of the compression stroke.

24. The method of claim 23 further including supplying a pressurized fuel directly to the chamber during a portion of a combustion stroke.

25. The method of claim 24, further including supplying the pressurized fuel during a portion of the compression stroke.

26. The method of claim 25, wherein supplying the pressurized fuel includes supplying a pilot injection at a predetermined crank angle before a main injection.

27. The method of claim 26, wherein said main injection begins during the compression stroke.

28. The method of claim 22, wherein said pressurizing includes a first stage of pressurization and a second stage of pressurization.

29. The method of claim 28, further including cooling air between said first stage of pressurization and said second stage of pressurization.

30. The method of claim 22, further including cooling the pressurized air prior to supplying said air to the intake manifold.

31. The method of claim 23, wherein said pressurizing includes a first stage of pressurization and a second stage of pressurization.

32. The method of claim 31, further including cooling air between said first stage of pressurization and said second stage of pressurization.

33. The method of claim 22, further including cooling the pressurized air prior to supplying said air to the intake manifold.

34. The method of claim 22, wherein pressurized air is supplied to the chamber in two charges.

35. The method of claim 34, wherein a primary charge is supplied to the chamber through a port controlled by an intake valve.

36. The method of claim 35, wherein a secondary charge is injected into the chamber during the compression stroke, at or after the intake valve is closed.

37. The method of claim 36, wherein the secondary charge is injected through a second port.

38. The method of claim 22, wherein said pressurizing includes pressurizing air to a ratio of at least 4:

1 with respect to atmospheric pressure.

39. The method of claim 38, further including:

maintaining fluid communication between the chamber and the intake manifold during an intake stroke and a majority of a compression stroke; and

supplying a fuel to the chamber during at least a portion of the remaining compression stroke.

40. The method of claim 39, wherein said majority is greater than 90 degrees crank angle after bottom dead center.

41. The method of claim 39, wherein said supplying fuel includes injecting a first portion of fuel a predetermined period prior to injecting a second portion of fuel.

42. The method of claim 41, wherein said injecting the second portion of fuel begins during the compression stroke and terminates during a combustion stroke.

43. The method of claim 39, further including cooling the air prior to supplying the air to the chamber.

44. The method of claim 30, including managing the pre-combustion conditions in the chamber of the engine.

45. The method of claim 30, 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.

46. The method of claim 1, wherein supplying pressurized air comprises supplying a mixture of pressurized air and recirculated exhaust gas from an intake manifold to an air intake port of a chamber in the cylinder, and wherein selectively operating comprises selectively operating and air intake valve to open the air intake port to allow the pressurized air and exhaust air mixture to flow between the chamber and the intake manifold substantially during a majority portion of a compression stroke of the piston.

47. The method of claim 22, wherein said pressurizing includes subjecting air to at least one stage of compression.

48. The method of claim 47, wherein said pressurizing includes subjecting air to two or more stages of compression.

49. The method of claim 48, wherein said pressurizing includes subjecting air to more than two stages of compression.

50. The method of claim 30, including providing, through motion of the piston, extra burn time for the combustion process.

51. A method of controlling a four stroke internal combustion engine having a variable compression ratio, said engine having a block defining a cylinder, a piston slidable in said cylinder, a head connected with said block, said piston, said cylinder, and said head defining a chamber, and said piston moving through a plurality of power cycles each involving an intake stroke, a compression stroke, an expansion stroke and an exhaust stroke, the method comprising:

pressurizing air;

supplying said air to an intake manifold of the engine;

maintaining fluid communication between the chamber and the intake manifold substantially during a majority portion of a compression stoke of the piston; and

supplying a pressurized fuel directly to the chamber during a portion of a combustion stroke.

52. The method of claim 51, wherein, maintaining fluid communication between the chamber and the intake manifold includes maintaining fluid communication between the chamber and the intake manifold during a portion of an intake stroke and through at least a majority portion of a compression stroke.

53. The method of claim 51, further including supplying the pressurized fuel during a portion of the compression stroke.

54. The method of claim 53, wherein supplying the pressurized fuel includes supplying a pilot injection at a predetermined crank angle before a main injection.

55. The method of claim 54, wherein said main injection begins during the compression stroke.

56. The method of claim 51, wherein said pressurizing includes a first stage of pressurization and a second stage of pressurization.

57. The method of claim 56, further including cooling air between said first stage of pressurization and said second stage of pressurization.

58. The method of claim 51, further including cooling the pressurized air.

59. The method of claim 51, wherein pressurized air is supplied to the chamber in two charges.

60. The method of claim 59, wherein a primary charge is supplied to the chamber through a port controlled by an intake valve.

61. The method of claim 60, wherein a secondary charge is injected into the chamber during the compression stroke, at or after the intake valve through which the primary charge is supplied has closed.

62. The method of claim 61, wherein the secondary charge is injected through a second port.

63. A four-stroke internal combustion engine including at least one cylinder and a piston slidable in the cylinder and moving through a plurality of power cycles each involving an intake stroke, a compression stroke, an expansion stroke and an exhaust stroke, the piston and cylinder defining, at least in part, a chamber within the engine, said engine further comprising:

an air intake port and an exhaust port associated with the chamber;

an air intake valve controllably movable to open and close the air intake port;

at least one compressor being in fluid communication with atmosphere and with the air intake port;

a fuel supply system operable to controllably inject fuel into the chamber; and

a first controller configured to selectively operate the air intake valve to remain open for a portion of a second half of the compression stroke of the piston, and

a second controller configured to introduce fuel into the chamber.

64. The engine of claim 63, wherein the at least one compressor comprises a first compressor being in fluid communication with the air intake port and a second compressor being in fluid communication with atmosphere and the first compressor.

65. The engine of claim 64, wherein at least one of said first compressor and said second compressor is coupled with a turbine of a turbocharger, said turbine being in fluid communication with the exhaust port.

66. The engine of claim 63, wherein the fuel supply system includes a fuel injector assembly.

67. The engine of claim 63, including means for cooling the air compressed by the at least one compressor.

68. The engine of claim 64, including means for cooling the air compressed by the second compressor.

69. The engine of claim 68, including means for cooling the air compressed by the first compressor.

70. The engine of claim 63, wherein said variable valve mechanism is actuated electronically.

71. The engine of claim 63, further including an air cooler between at least one of said first compressor and said second compressor and said air intake port.

72. The engine of claim 63, further including a second air intake port controlled by a second air intake valve.

73. The engine of claim 72, including a controller configured to open the second air intake valve at a point which is at or after the end of said portion of a second half of the compression stroke and before the end of the compression stroke.

74. The engine of claim 72, wherein the second air intake port is in fluid communication with the first compressor.

75. The engine of claim 63, wherein said second controller is configured to inject fuel into the chamber during a combustion stroke.

76. The engine of claim 64, wherein said second controller is configured to inject fuel into the chamber during a combustion stroke.

77. The engine of claim 63, further comprising an exhaust gas recirculation system operable to controllably provide a portion of exhaust gas from the exhaust port to an intake of the at least one compressor.

78. The engine of claim 63, wherein the at least one compressor comprises at least two compressors providing at least two stages of compression to air upstream of the air intake port.

79. The engine of claim 78, wherein the at least one compressor comprises at least three compressors providing at least there stages of compression to air upstream of the air intake port.

80. The engine of claim 67, wherein the piston is driven in a reciprocating motion by a crank on a crankshaft, the engine being so constructed that the piston is at top dead center of its path when the crank is at bottom dead center on the crankshaft.

81. The engine of claim 67, wherein the piston is driven in a reciprocating motion by the action of a crank acting directly or indirectly on a crank pin to which is attached a connecting rod to which is connected the piston, and wherein the engine is so constructed and arranged that, when the piston is around top dead center of its motion, the crank pin motion is subtracted from the straightening movement of the connecting rod.

82. The engine of claim 63, wherein the first controller is configured to operate the intake valve to be open substantially during a majority portion of the compression stroke of the piston.

83. The engine of claim 82, including means for cooling the air compressed by the at least one compressor.

84. The engine of claim 63, wherein the first controller is configured to operate the intake valve to be open during a portion of the intake stroke and through at least a majority portion of the compression stroke of the piston.

85. The engine of claim 84, including means for cooling the air compressed by the at least one compressor.