Patent ID: 8028665
Filing Date: 2011-10-04
Classification: F02B

Abstract:
1. A fuel burning, internal combustion, reciprocating piston engine, comprising in combination, two cylinders, one piston coaxially reciprocating within each cylinder, said pistons each linked by a connecting rod to a common rotable crankshaft, said crankshaft possessing a rotable output coupling to which a driven load may be connected, and further comprising in combination; (a) a first, fuel burning fired cylinder operating according to a four stroke cycle; (b) a second, selective expansion cylinder provided with means to alter its function back and forth, while said engine is running, from that of a fuel burning fired cylinder to that of a compound exhaust gas expansion cylinder, thereby effecting a secondary expansion of combustion gas transferred from said fired cylinder to said expansion cylinder within the span of one engine cycle; (c) said selective expansion cylinder provided with an intake valve with open and closed positions; (d) said selective expansion cylinder also provided with a first exhaust valve with open and closed positions; (e) said selective expansion cylinder also provided with a second exhaust valve with open and closed positions; (f) two combustion gas ports connecting a separate combustion gas conduit to each exhaust valve of said selective expansion cylinder; (g) an exhaust gas manifold diverter valve with open and closed positions; (h) means to actuate said exhaust gas manifold diverter valve open or closed such as, but not limited to, air bellows, hydraulic piston and cylinder, electric solenoid or electric motor; (i) an exhaust gas reservoir chamber; (j) an exhaust gas manifold possessing a plurality of conduits, separately connecting to each exhaust valve port for said selective expansion cylinder and to the exhaust port or ports of said fired cylinder, said gas conduits also connecting to said exhaust gas manifold diverter valve and to said exhaust gas reservoir chamber, said gas conduits further connecting to an exhaust gas discharge outlet; (k) said selective expansion cylinder also provided with a rotable shaft driven cam, said cam having a lobe to actuate said intake valve for said selective expansion cylinder, driven by said crankshaft, rotating at one half crankshaft speed; (l) said selective expansion cylinder also provided with first and second rotable shaft driven cams, each said cam having a lobe or lobes to actuate said first exhaust valve for said selective expansion cylinder, driven by said crankshaft, rotating at one half crankshaft speed, said first cam having one lobe shaped to urge said first exhaust valve open once every two crankshaft revolutions, thereby evacuating combustion exhaust gas from said cylinder according to a four stroke cycle, and said second cam having two lobes shaped to urge said first exhaust valve open once for each crankshaft revolution, thereby admitting combustion exhaust gas from said combustion exhaust manifold into said selective expansion cylinder once for each crankshaft revolution; (m) said selective expansion cylinder also provided with third and fourth rotable shaft driven cams, each said cam having a lobe shaped to actuate said second exhaust valve for said selective expansion cylinder, driven by said crankshaft, rotating at one half crankshaft speed, said third cam having one lobe shaped to urge said second exhaust valve open to evacuate gas from said selective expansion cylinder once every two crankshaft revolutions according to a four stroke cycle, and said fourth cam having one lobe clocked 180 degrees with respect to said third cam shaped to to enable said third and fourth cams in combination to urge said second exhaust valve open once for each crankshaft revolution, thereby evacuating gas from said selective expansion cylinder once for each crankshaft revolution; (n) said selective expansion cylinder also provided with a dis-engageable coupling interposed between said intake valve and said intake valve drive cam of said selective expansion cylinder that, when selected, decouples said intake valve cam from said intake valve, whereby said intake valve remains closed, and when deselected, couples said intake valve cam and said intake valve, thereby urging said intake valve open and closed according to a four stroke cycle; (o) said selective expansion cylinder also provided with a paired set of disengageable couplings, interposed between said first exhaust valve and said first and second drive cams of said selective expansion cylinder that, when selected, decouples said first drive cam from said first exhaust valve and couples said second drive cam with said first exhaust valve, said second drive cam thereby urging said second exhaust valve open once every crankshaft revolution, thereby admitting combustion exhaust gas from said exhaust gas manifold into said expansion cylinder once for each crankshaft revolution, and when deselected, decouples said second drive cam from said first exhaust valve and couples said first drive cam with said first exhaust valve, said first drive cam thereby urging said first exhaust valve open once every other crankshaft revolution, thereby evacuating combustion exhaust gas from said selective expansion cylinder according to a four stroke cycle; (p) said selective expansion cylinder also provided with a dis-engageable coupling interposed between said second exhaust valve and said fourth drive cam that, when selected, couples said second exhaust valve with said fourth drive cam, whereby, said fourth drive cam in combination with said third drive cam, together urge said second exhaust valve open once every crankshaft revolution, so as to evacuate combustion exhaust gas from said selective expansion cylinder once every crankshaft revolution, and when deselected, de-couples second exhaust valve from said fourth drive cam, whereby said third drive cam urges said second exhaust valve open once every two crankshaft revolutions to evacuate combustion exhaust gas from said selective expansion cylinder according to a four stroke cycle; (q) said selective expansion cylinder also provided with actuation means to select and de-select said dis-engageable couplings, such as, but not limited to, hydraulic piston and cylinder, electric solenoid or electric motor; (r) control means which, while said engine is running, automatically selects said compound mode exhaust gas expansion function when moderate engine power is required, and de-selects said compound mode exhaust gas expansion function when high engine power is required or when smooth engine operation at very low power settings or at idling speed is required, and; (s) control connections between said control means and the engine fuel system, exhaust gas manifold diverter valve and drive cam couplings, which conduct compound mode selective commands from said control means to shut off fuel supply to said selective expansion cylinder, if said engine is configured to deliver fuel to each cylinder individually, select said intake valve dis-engageable coupling, select said first exhaust valve paired set of dis-engageable couplings, select said second exhaust valve dis-engageable coupling, and close said exhaust gas manifold diverter valve, whereby said selective expansion cylinder functions in compound exhaust gas expansion mode, and alternatively, which conduct compound mode de-selective commands from said control means to deselect said intake valve dis-engageable coupling, deselect said first exhaust valve pair of dis-engageable couplings, deselect said second exhaust valve dis-engageable coupling, open said exhaust gas manifold diverter valve, and resume fuel supply to said expansion cylinder if said engine is configured to deliver fuel to each cylinder individually, such that both engine cylinders operate as fuel burning fired cylinders according to a four stroke cycle, whereby, said engine fuel efficiency increases after selecting said compound operating mode, and said engine power capacity maximizes after deselecting said compound operating mode.