Split four stroke engine

• US 6,609,371 B2
• Filed: 05/07/2002
• Issued: 08/26/2003
• Est. Priority Date: 07/20/2001
• Status: Expired due to Term

• Current Assignee: Scuderi Group, LLC
• Original Assignee: Scuderi Group, LLC
• Inventors: Scuderi, Carmelo J.
• Primary Examiner(s): NGUYEN, HOANG M
• Application Number:
  US10/139,981
• Publication Number:
  US 20030015171A1
• Time in Patent Office: 476 Days
• Field of Search: 605/97, 123/52.2, 123/52.3, 123/53.1, 123/53.3, 123/53.5
• US Class Current: 60/597
• CPC Class Codes: F02B 2075/027 four
• CPC Class Codes: F02B 33/22 with pumping cylinder situated at side of working cylinder, e.g. the cylinders being parallel
• CPC Class Codes: F02B 41/04 in main cylinders
• CPC Class Codes: F02B 75/02 Engines characterised by their cycles, e.g. six-stroke
• CPC Class Codes: F02B 75/228 with cylinders arranged in parallel banks
• CPC Class Codes: F02B 75/32 Engines characterised by connections between pistons and main shafts and not specific to preceding main groups
• CPC Class Codes: F02F 7/0019 Cylinders and crankshaft not in one plane (deaxation)
• CPC Class Codes: F02G 1/0535 Seals or sealing arrangements
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

A four stroke cycle internal combustion engine including a crankshaft, rotating about a crankshaft axis of the engine. A power piston is slidably received within a first cylinder and operatively connected to the crankshaft such that the power piston reciprocates through a power stroke and an exhaust stroke of a four stroke cycle during a single rotation of the crankshaft. A compression piston is slidably received within a second cylinder and operatively connected to the crankshaft such that the compression piston reciprocates through an intake stroke and a compression stroke of the same four stroke cycle during the same rotation of the crankshaft. The power piston reciprocates along a first piston-cylinder axis which is offset from the crankshaft axis. The offset substantially aligns a point of maximum combustion pressure applied to the power piston with a point of maximum torque applied to the crankshaft during the power stroke.

Claims

1. An engine comprising:

a crankshaft, rotating about a crankshaft axis of the engine;

a power piston slidably received within a first cylinder and operatively connected to the crankshaft such that the power piston reciprocates through a power stroke and an exhaust stroke of a four stroke cycle during a single rotation of the crankshaft;

a compression piston slidably received within a second cylinder and operatively connected to the crankshaft such that the compression piston reciprocates through an intake stroke and a compression stroke of the same four stroke cycle during the same rotation of the crankshaft; and

a first piston-cylinder axis along which the power piston reciprocates within the first cylinder, wherein the first piston-cylinder axis has an offset from the crankshaft axis such that the first piston-cylinder axis does not intersect the crankshaft axis;

wherein the offset of the first piston-cylinder axis substantially aligns a point of maximum combustion pressure applied to the power piston with a point of maximum torque applied to the crankshaft during the power stroke.

2. The engine of claim 1 comprising:

a gas passage interconnecting the first and second cylinders, the gas passage including an inlet valve and an outlet valve defining a pressure chamber therebetween;

wherein the inlet valve and the outlet valve of the gas passage substantially maintain at least a predetermined firing condition gas pressure in the pressure chamber during the entire four stroke cycle.

3. The engine of claim 1 wherein the power piston leads the compression piston by a phase shift angle that is substantially greater than zero.

4. The engine of claim 1 wherein the offset of the first piston-cylinder axis is such that the crankshaft must rotate at least 20 degrees past the point where the power piston reaches top dead center, before the power piston can reach a firing position.

5. The engine of claim 3 wherein the phase shift angle is approximately between 30 degrees and 60 degrees.

6. The engine of claim 3 comprising:

a second piston-cylinder axis along which the compression piston reciprocates within the second cylinder, wherein the second piston cylinder axis has an offset from the crankshaft axis such that the second piston-cylinder axis does not intersect the crankshaft axis and passes on an opposing side of the crankshaft axis relative to the first piston-cylinder axis.

7. An engine comprising:

a crankshaft, rotating about a crankshaft axis of the engine;

a power piston slidably received within a first cylinder and operatively connected to the crankshaft such that the power piston reciprocates through a power stroke and an exhaust stroke of a four stroke cycle during a single rotation of the crankshaft;

a compression piston slidably received within a second cylinder and operatively connected to the crankshaft such that the compression piston reciprocates through an intake stroke and a compression stroke of the same four stroke cycle during the same rotation of the crankshaft; and

a gas passage interconnecting the first and second cylinders, the gas passage including an inlet valve and an outlet valve defining a pressure chamber therebetween, wherein the inlet valve and the outlet valve of the gas passage substantially maintain at least a predetermined firing condition gas pressure in the pressure chamber during the entire four stroke cycle.

8. The engine of claim 7 comprising:

a first piston-cylinder axis along which the power piston reciprocates within the first cylinder, wherein the first piston cylinder axis has an offset from the crankshaft axis such that the first piston-cylinder axis does not intersect the crankshaft axis.

9. The engine of claim 8 wherein the power piston leads the compression piston by a phase shift angle that is substantially greater than zero.

10. The engine of claim 8 wherein the offset of the first piston-cylinder axis is such that the crankshaft must rotate at least 20 degrees past the point where the power piston reaches top dead center, before the power piston can reach a firing position.

11. The engine of claim 9 wherein the phase shift angle is approximately between 30 degrees and 60 degrees.

12. The engine of claim 10 comprising:

a second piston-cylinder axis along which the compression piston reciprocates within the second cylinder, wherein the second piston cylinder axis has an offset from the crankshaft axis such that the second piston-cylinder axis does not intersect the crankshaft axis and passes on an opposing side of the crankshaft axis relative to the first piston-cylinder axis.

13. The engine of claim 10 comprising:

the crankshaft having a first throw and a second throw;

a first connecting rod pivotally connected to both the power piston and the first throw of the crankshaft; and

a second connecting rod pivotally connected to both the compression piston and the second throw of the crankshaft;

wherein each of the first and second connecting rods has an angular bend of such magnitude that the connecting rod clears the bottom end of the associated one of the first and second cylinders.

14. The engine of claim 10 wherein the power and compression piston diameters are substantially different.

15. The engine of claim 13 wherein the first and second throws of the crankshaft have substantially different lengths.

37. The engine of claim 7 wherein the power and compression piston diameters are substantially different.

38. The engine of claim 7 comprising:

the crankshaft having a first and second crankshaft throw, the crankshaft throws having substantially different lengths.

16. An engine comprising:

a crankshaft, rotating about a crankshaft axis of the engine;

a power piston slidably received within a first cylinder and operatively connected to the crankshaft such that the power piston reciprocates through a power stroke and an exhaust stroke of a four stroke cycle during a single rotation of the crankshaft;

a compression piston slidably received within a second cylinder and operatively connected to the crankshaft such that the compression piston reciprocates through an intake stroke and a compression stroke of the same four stroke cycle during the same rotation of the crankshaft; and

a first piston-cylinder axis along which the power piston reciprocates within the first cylinder, wherein the first piston-cylinder axis has an offset from the crankshaft axis such that the first piston-cylinder axis does not intersect the crankshaft axis;

wherein the power piston leads the compression piston by a phase shift angle that is substantially equal to or greater than 20 degrees.

17. The engine of claim 16 comprising:

a gas passage interconnecting the first and second cylinders, the gas passage including an inlet valve and an outlet valve defining a pressure chamber therebetween, the inlet valve permitting substantially one way flow of compressed gas from the second cylinder to the pressure chamber and the outlet valve permitting substantially one way flow of compressed gas from the pressure chamber to the first cylinder;

wherein the inlet valve and the outlet valve of the gas passage substantially maintain at least a predetermined firing condition gas pressure in the pressure chamber during the entire four stroke cycle.

18. The engine of claim 16 wherein the phase shift angle is approximately between 30 degrees and 60 degrees.

19. The engine of claim 16 wherein the offset of the first piston-cylinder axis is such that the crankshaft must rotate at least 20 degrees past the point where the power piston reaches top dead center, before the power piston can reach a firing position.

20. The engine of claim 16 comprising:

a second piston-cylinder axis along which the compression piston reciprocates within the second cylinder, wherein the second piston cylinder axis has an offset from the crankshaft axis such that the second piston-cylinder axis does not intersect the crankshaft axis and passes on an opposing side of the crankshaft axis relative to the first piston-cylinder axis.

21. An engine comprising:

a crankshaft, rotating about a crankshaft axis of the engine;

a power piston slidably received within a first cylinder and operatively connected to the crankshaft such that the power piston reciprocates through a power stroke and an exhaust stroke of a four stroke cycle during a single rotation of the crankshaft;

a compression piston slidably received within a second cylinder and operatively connected to the crankshaft such that the compression piston reciprocates through an intake stroke and a compression stroke of the same four stroke cycle during the same rotation of the crankshaft; and

a piston-cylinder axis along which the compression piston reciprocates within the second cylinder, wherein the piston-cylinder axis has an offset from the crankshaft axis such that the piston-cylinder axis does not intersect the crankshaft axis;

wherein the power piston leads the compression piston by a phase shift angle that is substantially equal to or greater than 20 degrees.

22. The engine of claim 21 comprising a gas passage interconnecting the first and second cylinders, the gas passage including an inlet valve and an outlet valve defining a pressure chamber therebetween, the inlet valve permitting substantially one way flow of compressed gas from the second cylinder to the pressure chamber and the outlet valve permitting substantially one way flow of compressed gas from the pressure chamber to the first cylinder;

wherein the inlet valve and the outlet valve of the gas passage substantially maintain at least a predetermined firing condition gas pressure in the pressure chamber during the entire four stroke cycle.

23. The engine of claim 21 wherein the phase shift angle is approximately between 30 degrees and 60 degrees.

24. An engine comprising:

a crankshaft, rotating about a crankshaft axis of the engine;

a power piston slidably received within a first cylinder and operatively connected to the crankshaft such that the power piston reciprocates through a power stroke and an exhaust stroke of a four stroke cycle during a single rotation of the crankshaft;

a compression piston slidably received within a second cylinder and operatively connected to the crankshaft such that the compression piston reciprocates through an intake stroke and a compression stroke of the same four stroke cycle during the same rotation of the crankshaft; and

a first piston-cylinder axis along which the power piston reciprocates within the first cylinder, wherein the first piston-cylinder axis has an offset from the crankshaft axis such that the first piston-cylinder axis does not intersect the crankshaft axis;

wherein the offset of the first piston-cylinder axis is such that the crankshaft must rotate at least 20 degrees past the point where the power piston reaches top dead center, before the power piston can reach a firing position.

25. The engine of claim 24 comprising:

the crankshaft having a first throw and a second throw;

a first connecting rod pivotally connected to both the power piston and the first throw of the crankshaft; and

a second connecting rod pivotally connected to both the compression piston and the second throw of the crankshaft;

wherein each of the first and second connecting rods has an angular bend of such magnitude that the connecting rod clears the bottom end of the associated one of the first and second cylinders.

26. The engine of claim 24 wherein the power and compression piston diameters are substantially different.

27. The engine of claim 25 wherein the first and second throws of the crankshaft have substantially different lengths.

28. An engine comprising:

a crankshaft, rotating about a crankshaft axis of the engine;

a power piston slidably received within a first cylinder and operatively connected to the crankshaft via first linkage system such that the power piston reciprocates through a power stroke and an exhaust stroke of a four stroke cycle during a single rotation of the crankshaft;

a compression piston slidably received within a second cylinder and operatively connected to the crankshaft via second linkage system, wherein the first and second linkage systems share no common mechanical link, and such that the compression piston reciprocates through an intake stroke and a compression stroke of the same four stroke cycle during the same rotation of the crankshaft;

a first piston-cylinder axis along which the power piston reciprocates within the first cylinder; and

a second piston-cylinder axis along which the compression piston reciprocates within the second cylinder;

wherein one of the first and second piston-cylinder axes has an offset from the crankshaft axis.

29. The engine of claim 28 comprising:

a gas passage interconnecting the first and second cylinders, the gas passage including an inlet valve and an outlet valve defining a pressure chamber therebetween, the inlet valve permitting substantially one way flow of compressed gas from the second cylinder to the pressure chamber and the outlet valve permitting substantially one way flow of compressed gas from the pressure chamber to the first cylinder.

31. The engine of claim 28 wherein the power and compression piston diameters are substantially different.

32. The engine of claim 28 wherein the power piston leads the compression piston by a phase shift angle that is substantially greater than zero.

33. The engine of claim 28 comprising:

the crankshaft having a first and second crankshaft throw;

the first linkage system pivotally connected to the first crankshaft throw; and

the second linkage system pivotally connected to the second crankshaft throw.

34. The engine of claim 28 wherein the offset of the first piston-cylinder axis is such that the crankshaft must rotate at least 20 degrees past the point where the power piston reaches top dead center, before the power piston can reach a firing position.

35. The engine of claim 32 wherein the phase shift angle is at least 20 degrees.

36. The engine of claim 33 wherein the first and second throws of the crankshaft have substantially different lengths.

30. The engine of claim comprising:

a gas passage interconnecting the first and second cylinders, the gas passage including an inlet valve and an outlet valve defining a pressure chamber therebetween, wherein the inlet valve and the outlet valve of the gas passage substantially maintain at least a predetermined firing condition gas pressure in the pressure chamber during the entire four stroke cycle.