Continuously variable displacement engine

A variable-displacement engine comprising:

• an engine block;
• an elongated power shaft rotatably supported by the engine block, the power shaft having a longitudinal power shaft axis defining an axial direction and being fixed axially relative to the engine block;
• a rotating cylinder block defining at least one cylinder, each cylinder having a bore defining a bore axis aligned substantially parallel to the power shaft axis, the cylinder block being fixedly mounted to the power shaft such that when the power shaft rotates, the cylinder block rotates around the power shaft axis and each bore axis revolves around the power shaft axis;
• one or more pistons corresponding in number to the number of the cylinders, each respective piston being slidably disposed within the bore of a respective cylinder;
• one or more connecting rods corresponding in number to the number of cylinders, each respective connecting rod having an upper end connected to a respective piston and a lower end connected to a respective connecting rod bearing;
• a wobble plate assembly having a generally annular configuration defining a central opening through which the power shaft passes, the wobble plate assembly including
• a rotating first ring portion, the first ring portion including one or more bearing mounting arms formed thereon, corresponding in number to the number of the connecting rods, each bearing mounting arm having the respective connecting rod bearing mounted thereon, and
• a non-rotating second ring portion, the second ring portion being rotatably slidably connected to the first ring portion so as to allow the first ring portion to rotate relative to the second ring portion about a common ring center line while constraining the second ring portion to remain parallel to the first ring portion, and
• a rotation-locking assembly connected between the first ring portion and the power shaft to rotationally lock the first ring portion to the power shaft while allowing the first ring portion to vary an angle of inclination with respect to the power shaft axis,
• the wobble plate assembly defining a wobble plate inclination plane being a plane passing through the centers of the connecting rod bearings, a wobble plate pivot axis being a line lying in the wobble plate inclination plane and intersecting the longitudinal power shaft axis in a perpendicular orientation and rotating with the power shaft, and a wobble plate angle θ being an angle of intersection between the wobble plate inclination plane and a plane normal to the power shaft axis when viewed in a direction parallel to the pivot axis;
• a piston control mechanism including
• a lift mechanism mounted on the engine block and operatively connected to a first location on the non-rotating second ring portion to selectively move the first location on the second ring portion in an axial direction, and
• an axial anchor arm extending from a second location on the non-rotating second ring portion to an outer end connected to a bearing anchor point mounted on the engine block at an axially fixed position;
• whereby operation of the lift mechanism to selectively change the axial position of the first location of the second ring portion selectively changes the wobble plate angle θ and an axial distance d between the wobble plate pivot axis and a theoretical zero angle point, which in turn selectively changes the piston displacement of the engine while maintaining the compression ratio of the engine at a substantially constant value.

A variable-displacement engine comprising:

• an engine block;
• an elongated power shaft rotatably supported by the engine block, the power shaft having a longitudinal power shaft axis defining an axial direction and being fixed axially relative to the engine block;
• a cylinder block fixedly mounted to the engine block, the cylinder block defining at least one cylinder, each cylinder having a bore defining a bore axis aligned substantially parallel to the power shaft axis;
• one or more pistons corresponding in number to the number of the cylinders, each respective piston being slidably disposed within the bore of a respective cylinder;
• one or more connecting rods corresponding in number to the number of cylinders, each respective connecting rod having an upper end connected to a respective piston and a lower end connected to a respective connecting rod bearing;
• a wobble plate assembly having a generally annular configuration defining a central opening through which the power shaft passes, the wobble plate assembly including
• a non-rotating first ring portion, the first ring portion including one or more bearing mounting arms formed thereon, corresponding in number to the number of the connecting rods, each bearing mounting arm having the respective connecting rod bearing mounted thereon, and
• a rotating second ring portion, the second ring portion being rotatably slidably connected to the first ring portion so as to allow the second ring portion to rotate relative to the first ring portion about a common ring center line while constraining the second ring portion to remain parallel to the first ring portion, and
• a rotation-locking assembly connected between the first ring portion and the engine block to rotationally lock the first ring portion to the engine block while allowing the first ring portion to vary an angle of inclination with respect to the power shaft axis,
• the wobble plate assembly defining a wobble plate inclination plane being a plane passing through the centers of the connecting rod bearings, a wobble plate pivot axis being a line lying in the wobble plate inclination plane and intersecting the longitudinal power shaft axis in a perpendicular orientation and rotating with the power shaft, and a wobble plate angle θ being an angle of intersection between the wobble plate inclination plane and a plane normal to the power shaft axis when viewed in a direction parallel to the pivot axis;
• a piston control mechanism including
• an anchor support member attached to the power shaft to rotate with the power shaft and extending radially outward from the power shaft to an outer end;
• a lift mechanism slidably mounted on the power shaft for axial movement along the power shaft axis,
• a lever beam supported at a first location by pivot bearings mounted to the lift mechanism along a normal line passing through the power shaft axis parallel to the wobble plate pivot axis and supported at a second location by an axial anchor bearing carried by the anchor support member, thereby defining a lever beam centerline passing through the centers of the pivot bearing and the axial anchor bearing and an lever beam angle being an angle between the lever beam centerline and a plane normal to the power shaft axis when viewed in a direction parallel to the pivot axis;
• two or more spaced-apart connecting links, each connecting link having a first end connected to the second ring portion of the wobble plate and a second end connected to the lever beam;
• whereby operation of the lift mechanism to selectively change the axial position of the lever beam pivot bearings selectively changes the lever beam angle, which in turn selectively changes, via the connecting links, the wobble plate angle θ and an axial distance d between the wobble plate pivot axis and a theoretical zero angle point, which in turn selectively changes the piston displacement of the engine while maintaining the compression ratio of the engine at a substantially constant value.