1. A variable-displacement piston-cylinder device comprising:
a cylinder, said cylinder defining at least two generally cylindrical chambers in substantially coaxial arrangement and having different diameters;
an inlet at each of said at least two chambers, each of said inlets being adapted to selectively conduct a fluid into a respective one of said at least two chambers;
an outlet at each of said at least two chambers, each of said outlets being adapted to conduct a fluid out of the respective one of said at least two chambers;
a piston, said piston comprising at least two piston members joined to one another in substantially coaxial arrangement and having different diameters corresponding to the different diameters of said cylindrical chambers, wherein each of said at least two piston members is movably and reciprocally received in a respective one of said at least two chambers to define a displacement volume for each of said cylindrical chambers;
a controller, said controller being operable to select whether the fluid is conducted into either of said at least two chambers via said inlets; and
wherein each of said at least two chambers is independently activatable and deactivatable by said controller selecting whether the fluid is conducted into either of said at least two chambers via said inlets.
2. The piston-cylinder device of claim 1, wherein said cylinder defines at least three generally cylindrical chambers having different diameters and said piston comprises at least three piston members.
3. The piston-cylinder device of claim 1, wherein said piston-cylinder device comprises at least one chosen from a combustion engine, a steam engine, an air engine, a fluid pump, or a fluid compressor.
4. The piston-cylinder device of claim 3, wherein said piston-cylinder device comprises a combustion engine and wherein the fluid comprises a combustible fluid.
5. The piston-cylinder device of claim 4, wherein said combustion engine comprises an ignition source at each of said chambers; and wherein said controller is operable to independently activate and deactivate each of said ignition sources.
6. The piston-cylinder device of claim 4, wherein said piston-cylinder device comprises a compression-ignition combustion engine.
7. The piston-cylinder device of claim 4, wherein said piston-cylinder device comprises a combustion engine and at least one chosen from a fluid pump and a fluid compressor.
8. The piston-cylinder device of claim 7, wherein at least one of said at least two generally cylindrical chambers comprises at least two of said inlets for conducting at least two different fluids into said at least one of said cylindrical chambers.
9. The piston-cylinder device of claim 8, wherein said at least one of said cylindrical chambers is operable as either a combustion engine or a fluid pump.
10. The piston-cylinder device of claim 9, wherein said controller is operable to change the operation of said at least one of said cylindrical chambers between operation as a combustion engine and operation as a fluid pump while said piston-cylinder device is operating.
11. The piston-cylinder device of claim 1, further comprising a valve at each of said inlets, each of said valves being independently operable by said controller to open and close a respective one of said inlets.
12. The piston-cylinder device of claim 1, wherein said displacement volume of each of said cylindrical chambers is approximately one unit volume larger or smaller than an adjacent one of said cylindrical chambers.
13. The piston-cylinder device of claim 1, wherein said displacement volume of each of said cylindrical chambers is approximately one-half the displacement volume andor double the displacement volume of an adjacent one of said cylindrical chambers.
14. The piston-cylinder device of claim 1, further comprising:
at least two of said cylinders;
at least two of said pistons corresponding to said cylinders;
a connecting rod pivotally coupled to each of said pistons via a wrist pin;
a crankshaft, said crankshaft coupled to said pistons by said connecting rods; and
wherein said controller is operable to simultaneously control the activation and deactivation of the respective chambers of each of said cylinders in a substantially identical manner so that each of said cylinders exhibits a substantially identical effective displacement.
15. A variable-displacement reciprocating combustion engine comprising:
a cylinder, said cylinder defining at least two generally cylindrical chambers in substantially coaxial arrangement and having different diameters;
an inlet at each of said at least two chambers, each of said inlets comprising a valve to selectively conduct a combustible fluid into a respective one of said at least two chambers;
an outlet at each of said at least two chambers, each of said outlets comprising a valve to selectively conduct a fluid out of the respective one of said at least two chambers;
a piston, said piston defining at least two piston members joined to one another in substantially coaxial arrangement and having different diameters corresponding to the different diameters of said cylindrical chambers, wherein each of said at least two piston members is movably and reciprocally received in a respective one of said at least two chambers to define a displacement volume for each of said cylindrical chambers;
a controller, said controller being operable to select whether the fluid is conducted into either of said at least two chambers via said inlets; and
wherein each of said at least two chambers is independently activatable and deactivatable by said controller selecting whether the combustible fluid is conducted into either of said at least two chambers via said inlets.
16. The combustion engine of claim 15, further comprising an ignition source at each of said chambers, each of said ignition sources being independently energizable by said controller, wherein each of said at least two chambers is independently activatable and deactivatable by said controller selecting which of said ignition sources is energized to cause combustion of said fluid.
17. The combustion engine of claim 15, wherein said combustion engine comprises a compression-ignition engine.
18. The combustion engine of claim 17, further comprising an ignition source at least one of said chambers, each of said ignition sources being independently energizable by said controller to cause combustion of said fluid.
19. The combustion engine of claim 18, wherein said at least one generally cylindrical chamber comprising said ignition source exhibits a different compression ratio than the other generally cylindrical chambers.
20. The combustion engine of claim 19, wherein at least one generally cylindrical chamber comprising said ignition source is operable on a different combustible fluid than the other generally cylindrical chambers.
21. The combustion engine of claim 15, wherein each of said at least two chambers is further independently activatable and deactivatable by said controller selecting whether the combustible fluid is conducted out of either of said at least two chambers via said outlets.
22. The combustion engine of claim 15, wherein said cylinder defines at least three generally cylindrical chambers having different diameters and said piston comprises at least three piston members.
23. The combustion engine of claim 22, wherein said cylinder defines at least four generally cylindrical chambers having different diameters and said piston comprises at least four piston members.
24. The combustion engine of claim 15, wherein said controller receives chamber status data and throttle position data to select which of said at least two chambers to independently activate or deactivate.
25. The combustion engine of claim 24, wherein said controller receives data chosen from at least one of fuel type, engine temperature, exhaust gas properties, ambient temperature, ambient humidity, barometric pressure, emissions, crankshaft angle, engine speed, transmission speed, emission timing valve timing, vehicle braking status, traction control status, brakes status, suspension status, navigational data, safety systems status, active strategy, transient mode, or operator profile.
26. The combustion engine of claim 15, wherein said displacement volume of each of said cylindrical chambers is approximately one unit volume larger or smaller than an adjacent one of said cylindrical chambers.
27. The combustion engine of claim 15, wherein said displacement volume of each of said cylindrical chambers is approximately one-half the displacement volume andor double the displacement volume of an adjacent one of said cylindrical chambers.
28. The combustion engine of claim 15, comprising:
at least two of said cylinders;
at least two of said pistons corresponding to said cylinders;
a connecting rod pivotally coupled to each of said pistons via a wrist pin;
a crankshaft, said crankshaft being rotatably drivable by said connecting rods in response to reciprocating motion of said pistons; and
wherein said controller is operable to simultaneously control the activation and deactivation of the respective chambers of each of said cylinders in a substantially identical manner so that each of said cylinders exhibits a substantially identical power output.
29. A method of controlling a variable-displacement piston-cylinder device, said method comprising:
providing a cylinder defining at least two generally cylindrical chambers in substantially coaxial arrangement and having different diameters;
providing a piston comprising at least two piston members joined to one another in substantially coaxial arrangement and having different diameters corresponding to the different diameters of said cylindrical chambers;
providing a controller;
positioning the piston in the cylinder so that each of the piston members is movably and reciprocally received in a respective one of the chambers to define a displacement volume for each of the cylindrical chambers;
independently controlling, via the controller, fluid flow through fluid inlets to any single cylindrical chamber or combination of the cylindrical chambers; and
independently controlling, via the controller, fluid flow through the outlets out of any single cylindrical chamber or combination of the cylindrical chambers.
30. The method of claim 29, further comprising providing a combustible fluid to at least one of the generally cylindrical chambers.
31. The method of claim 30, further comprising:
operating the at least one of the generally cylindrical chambers receiving the combustible fluid as a combustion engine; and
operating another of the generally cylindrical chambers as a fluid pump or compressor.
32. The method of claim 30, further comprising:
providing an ignition source at the at least one of the generally cylindrical chambers receiving the combustible fluid as a combustion engine; and
controlling the ignition source via the controller.
33. The method of claim 29, wherein said independently controlling fluid flow through fluid inlets comprises opening and closing valves in the fluid inlets, and wherein said independently controlling fluid flow through the outlets comprises opening and closing valves in the fluid outlets.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A system for inserting an implant comprising:
a trial assembly configured for insertion between vertebrae in a patient and removal therefrom, wherein the trial assembly comprises:
a handle portion;
a cylindrical base portion coupled to the handle portion, wherein the cylindrical base portion comprises:
an outer cylinder;
a drive shaft configured to be coaxially received in the outer cylinder, wherein the drive shaft includes a gear at its distal end, wherein the drive shaft is configured to rotate about a longitudinal axis of the cylindrical base portion; and
a scale configured to threadingly receive the drive shaft within the scale; and
a tip assembly configured to expand, wherein the tip assembly comprises:
an outer member;
an upper gear member configured to engage the gear on the drive shaft and engage the outer member;
an inner member configured to be coaxially received within the outer member; and
a lower gear member configured to engage the gear on the drive shaft and engage the inner member,
wherein the scale is configured to measure expansion of the tip assembly and
wherein the upper gear member and the lower gear member are capable of moving with respect to each other;
an expandable implant configured for insertion into a patient’s spine, the expandable implant having a longitudinal axis and comprising a gear member configured to expand the expandable implant; and
the expandable implant configured to be inserted between the vertebrae in the patient and expanded, wherein the scale on the trial assembly provides a measurement of expansion of the tip assembly to give a measurement for a height of expansion of the expandable implant; and
an inserter tool comprising: an inserter tip assembly having a base portion and a central shaft disposed in a through-bore in the base portion, wherein the central shaft is configured to engage the expandable implant, arms for engaging slots of the expandable implant and an implant engagement gear for engaging the gear member of the expandable implant,
a primary gear mechanism configured to transfer rotation of a primary drive shaft to the expandable implant to cause expansion of the expandable implant; and
a secondary gear mechanism configured to transfer rotation of a secondary drive shaft to the central shaft,
wherein the inserter tool is configured to cause the tip assembly of the inserter tool to angulate.
2. The system of claim 1, wherein the scale is keyed to the outer cylinder.
3. The system of claim 1, wherein the outer cylinder comprises one or more visual indicators of the expansion of the trial assembly, and wherein the scale includes a viewing window for the one or more visual indicators.
4. The system of claim 3, wherein the scale comprises one or more visual indicators of the expansion of the trial assembly.
5. The system of claim 1, wherein an endplate for engaging a first vertebral body is coupled to the inner member, and wherein an endplate for engaging a second vertebral body is coupled to the outer member.
6. The system of claim 1, wherein a pin secures the inner and outer members in rotational position with respect to one another.
7. The system of claim 1, wherein the expandable implant comprises:
an inner member having a hollow interior portion and a threaded external portion and including a first end portion configured to engage the first vertebral body; and
an outer member having a hollow interior portion configured to coaxially receive the inner member therein and including a second end portion configured to engage a second vertebral body, wherein the inner and outer members are moveable relative to each other along the longitudinal axis of the expandable implant;
the gear member positioned coaxial to the inner member and the outer member and axially fixed to the outer member and freely rotatable with respect to the outer member,
wherein the gear member threadingly engages the threaded portion of the inner member.
8. The system of claim 1, wherein the inserter tool has a longitudinal axis and is configured for insertion of the expandable implant between the vertebrae, wherein the inserter tool comprises:
a handle portion;
a cylindrical base portion coupled to the handle portion, wherein the cylindrical base portion comprises:
an outer cylinder;
an internal shaft configured to be coaxially received within the outer cylinder;
the primary drive shaft configured to be coaxially received within the internal shaft; and
the secondary drive shaft configured to be coaxially received within the primary drive shaft; and
the inserter tip assembly positioned at a distal end of the base portion,
wherein the internal shaft is configured to engage the inserter tip assembly such that the inserter tip assembly is configured to rotate about a pin coupled between the base portion and the inserter tip assembly upon distal advancement of the internal shaft.