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US 10,550,737 B2Granted
High efficiency steam engine having improved steam cutoff control
AssigneeThermal Power Recovery LLC
InventorJames V. Harmon, Sr.
Life of this patent
Estimating the term…
Abstract
A high efficiency uniflow steam engine with automatic inlet and exhaust valves rather than camshaft operated valves includes an electromagnet and cooperating armature that actuates a cutoff control valve for closing a steam inlet valve at any time selected to stop the flow of steam to the cylinder. Approaching the end of the exhaust stroke typically 0.12 inch before TDC the cylinder is sealed thereby compressing the remaining residual steam down to a minute clearance approaching zero, for example, 0.020 inch to raise cylinder steam pressure enough to open the steam inlet valve without physical contact between the piston and the steam inlet valve thereby eliminating tappet noise, shock and wear.
Claims14
A steam engine comprising;
- at least one cylinder having a piston that is sealingly and slidably mounted therein at an end of a steam expansion chamber and is operatively connected to a crankshaft;
- the engine having a steam supply port;
- a steam inlet valve that is constructed to seal a valve seat in the steam engine that communicates between the steam supply port and the steam expansion chamber;
- a steam exhaust valve communicating with the steam expansion chamber;
- an electric control unit connected to an electromagnet constructed for holding an armature proximate thereto when electric current is supplied thereto, the armature being operatively associated with the steam inlet valve;
- and
- a cutoff valve that is mounted in the steam engine for reciprocation and is responsive to actuation by movement of the armature of the electromagnet to close the steam inlet valve for the cutting off an admission of steam to the expansion chamber.
4 more elements
A steam engine comprising;
- at least one cylinder having a piston that is sealingly and slidably mounted therein at one end of a steam expansion chamber and is operatively connected to a crankshaft;
- the engine having a steam supply port;
- a steam inlet valve mounted in the engine that is constructed when in a closed position to seal a valve seat in the engine that communicates between the steam supply port and the steam expansion chamber;
- a steam exhaust valve mounted for reciprocation in the engine in communication with the steam expansion chamber for exhausting steam therefrom;
- a spring supported by the steam exhaust valve in a position to operate a cutoff control valve in the engine that communicates with the steam expansion chamber, said cutoff control valve being moved by the spring when the piston approaches a top dead center position thereby closing the cutoff control valve;
- and
- an electric control unit operatively connected to control an operation of at least one valve.
4 more elements
A steam engine comprising;
- at least one cylinder having a piston that is sealingly and slidably mounted therein at one end of a steam expansion chamber and is operatively connected to a crankshaft;
- the engine having a steam supply port;
- a steam inlet valve that is constructed to seal a valve seat in the engine that communicates between the steam supply port and the steam expansion chamber;
- a steam exhaust valve communicating with the steam expansion chamber;
- a cutoff control valve mounted for movement in the engine that is constructed and arranged to seal an outlet to the steam expansion chamber;
- a lifter supported to reciprocate with the piston in a position to close the cutoff control valve as the piston approaches top dead center thereby sealing the steam expansion chamber proximate but prior to an end of an exhaust stroke such that a residual quantity of steam remaining in the steam expansion chamber is compressed by movement of the piston proximate the end of the exhaust stroke to a pressure that opens the inlet valve in response to a force applied to the inlet valve by the steam thus compressed;
- and
- an electric control unit connected to the electromagnet.
5 more elements
A steam engine comprising;
- at least one cylinder having a piston that is sealingly and slidably mounted therein at one end of a steam expansion chamber and is operatively connected to a crankshaft;
- the engine having a steam supply port;
- a steam inlet valve that is constructed to seal a valve seat in the engine that communicates between the steam supply port and the steam expansion chamber;
- a steam exhaust valve communicating with the steam expansion chamber;
- a cutoff control valve that is slidably mounted for reciprocation and is positioned to seal communication between the steam expansion chamber and a cutoff control chamber located in the engine that is in communication with the cutoff control valve and the steam inlet valve;
- an electromagnet having an armature operatively associated to allow the cutoff control valve to move at a selected time in a cycle of engine operation for admitting steam into the cutoff control chamber to enable the inlet valve to close thereby cutting off the flow of steam to the steam expansion chamber;
- and
- an electric control unit connected to the electromagnet.
5 more elements
Dependencies are inferred from the claim text.