Opposed piston engine
AssigneeAchates Power, Inc.
InventorsJames U. Lemke, Ronald J. Hoffman, Michael H. Wahl, Patrick R. Lee
Life of this patent
Estimating the term…
Abstract
A two-cycle, opposed piston engine with side-mounted crankshafts and cylinders isolated from mechanical stresses of the engine includes tailored cooling of cylinders and symmetrical cooling of the interior surfaces of piston crowns. Each opposed piston includes a compliant member that permits movement of an axially-centered rod mounted in the piston in order to maintain axial alignment with the bore of a cylinder in which the piston is disposed during engine operation. A single wristpin is disposed externally of the piston to connect the piston with connecting rods that run between the piston and the crankshafts.
Claims44
An opposed piston engine including two side-mounted crankshafts and at least one pair of opposed pistons, each piston connected to the two crankshafts by connecting rods and a single wristpin external to the piston, in which each piston includes a cylindrical body, an open end, a closed end defining a crown, and passages positioned for directing symmetric flows of liquid coolant to a back surface of the crown of the piston.
An opposed piston engine including two side-mounted crankshafts and at least one pair of opposed pistons, each piston connected to the two crankshafts by connecting rods and a single wristpin external to the piston, a rod for each piston, in which each piston includes a cylindrical body with an open end and a closed end defining a crown, each rod having a first end attached to the piston near a back surface of the crown of the piston and a second end extending through the open end of the piston, the single wristpin for the piston being attached to the second end, and each rod being a tubular rod for directing a flow of liquid coolant to the passages.
An opposed piston internal-combustion engine, comprising:
- a cylinder having central and end portions and a bore;
- a supply system means for applying streams of a liquid coolant to the cylinder that flow from the central portion toward the end portions;
- first and second opposed pistons disposed to reciprocate in the bore, each piston including a crown having a back surface;
- the supply system means further for applying a flow of liquid coolant to an internal portion of each piston on the back surface of the crown of the piston;
- and
- a single wristpin external to each piston.
An opposed piston internal-combustion engine, comprising:
- a cylinder having a grooved surface, central and end portions, and a bore;
- a supply system for applying streams of a liquid coolant to the grooved surface that flow from the central portion toward the end portions;
- and
- first and second opposed pistons in the bore, each piston including a crown having a back surface and a compliant boot;
- a rod for each piston, each rod having a first end within received in the compliant boot of the respective piston and a second end outside the piston, and
- a single wristpin for each piston, each wristpin mounted on the second end of the rod for the piston;
- the supply system further for applying streams of liquid coolant to an internal portion of each piston on the back surface of the crown.
An opposed piston internal-combustion engine, comprising:
- a cylinder with a liner, the liner having a bore, an outside surface, a central portion, an exhaust end and an inlet end;
- a first group of grooves on the outside surface to conduct a liquid coolant from the central portion toward the exhaust end;
- a second group of grooves on the outside surface to conduct a liquid coolant from the central portion toward the inlet end;
- a third group of grooves on the outside surface to conduct a liquid coolant circumferentially in the central portion;
- first and second opposed pistons disposed in the bore, each piston including a crown;
- a single wristpin mounted externally to each piston;
- a coolant channel to apply streams of a liquid coolant to an internal portion of the first piston on a back surface of the crown;
- and
- a coolant channel to apply streams of a liquid coolant to an internal portion of the second piston on a back surface of the crown.
An opposed piston internal-combustion engine, comprising:
- a cylinder with a liner, the liner having a bore, an outside surface, a central portion, an exhaust end and an inlet end;
- a first group of grooves on the outside surface to conduct a liquid coolant from the central portion toward the exhaust end;
- a second group of grooves on the outside surface to conduct a liquid coolant from the central portion toward the inlet end;
- a third group of grooves on the outside surface to conduct a liquid coolant circumferentially in the central portion;
- first and second opposed pistons disposed in the bore, each piston including a crown and means for compliant adjustment of the piston with respect to the cylinder;
- a plurality of passages in the first piston to apply streams of a liquid coolant to an internal portion of the first piston on a back surface of the crown;
- and
- a plurality of passages in the second piston to apply streams of a liquid coolant to an internal portion of the second piston on a back surface of the crown.
An opposed piston internal-combustion engine, comprising:
- a cylinder with a liner, the liner having a bore, an outside surface, a central portion, an exhaust end and an inlet end;
- a first group of grooves on the outside surface to conduct a liquid coolant from the central portion toward the exhaust end;
- a second group of grooves on the outside surface to conduct a liquid coolant from the central portion toward the inlet end;
- a third group of grooves on the outside surface to conduct a liquid coolant circumferentially in the central portion;
- first and second opposed pistons disposed in the bore, each piston including a crown and means for compliant adjustment of the piston with respect to the cylinder;
- a single wristpin mounted externally to each piston;
- a plurality of passages in the first piston to apply streams of a liquid coolant to an internal portion of the first piston on a back surface of the crown;
- and
- a plurality of passages in the second piston to apply streams of a liquid coolant to an internal portion of the second piston on a back surface of the crown.
An opposed piston internal-combustion engine, comprising:
- a cylinder with a grooved surface, central and end portions, and a bore;
- a supply system for applying streams of a liquid coolant on the grooved surface that flow from the central portion toward the end portions;
- first and second opposed pistons disposed to reciprocate in the bore;
- a single wristpin mounted to each piston to couple reciprocating motion to the piston;
- and,
- means in each piston for causing compliant adjustment of the piston with respect to the cylinder.
An opposed piston engine including two side-mounted crankshafts, at least one pair of opposing pistons, and a single wristpin external to each piston coupling the respective piston to the two crankshafts, in which each piston includes a cylindrical body with an open end and a closed end defining a crown, the engine further including a rod for each piston, each rod being coaxial with the cylindrical body of a respective piston and having a first end attached to the piston near the back surface of the crown of the piston and a second end extending through the open end of the piston, the single wristpin for the piston being attached to the second end of the rod, and in which each rod is a tubular rod with a bore for directing a flow of liquid coolant toward the back surface of the crown of a respective piston.
An opposed piston engine including at least one cylinder that is primarily a cooled pressure vessel and a frame supporting the cylinder, in which the cylinder includes:
- a liner having an outside surface, central and end portions, and port openings in each end portion;
- a sleeve on the liner extending from the central portion toward the end portions;
- and,
- port manifolds on the liner over the end portions and continuous with the sleeve, and in which the cylinder further includes:
- groups of grooves that extend on the outside surface of the liner from the central portion toward the end portions, and a group of grooves that extend substantially circumferentially in the central portion;
- and
- one or more pipes in the sleeve, each pipe in communication with a respective groove and with a source of liquid coolant.
Dependencies are inferred from the claim text.