Hybrid Vehicle Vibration Reduction System and Method
A method for reducing vibration in a hybrid-electric vehicle including initiating a shut-down sequence of an internal combustion engine of the a hybrid-electric vehicle; providing an open port to at least one combustion chamber of the internal combustion engine; and shutting down the internal combustion engine.
1 . A method for reducing vibration in a hybrid-electric vehicle, the hybrid-electric vehicle including an internal combustion engine, the method comprising:
initiating a shut-down sequence of the internal combustion engine;
providing an open port to at least one combustion chamber of the internal combustion engine; and,
shutting down the internal combustion engine.
2 . The method of claim 1 , further comprising automatically determining that engine operation is no longer necessary based on predetermined parameters; and,
wherein the initiating the shut-down sequence comprises automatically initiating the shut-down sequence in response to the automatically determining that engine operation is no longer necessary.
3 . The method of claim 2 , wherein the automatically determining that engine operation is no longer necessary comprises receiving an output from an Idle-Stop algorithm.
4 . The method of claim 1 , further comprising shutting off ignition to the internal combustion engine before the providing the open port to at least one combustion chamber of the internal combustion engine.
5 . The method of claim 1 , further comprising shutting off fuel supply to the internal combustion engine before the providing the open port to at least one combustion chamber of the internal combustion engine.
6 . The method of claim 5 , further comprising cycling the engine one or more times to clear fuel from the internal combustion engine.
7 . The method of claim 5 , further comprising confirming that the at least one combustion chamber of the internal combustion engine is clear of fuel before providing an open port to at least one combustion chamber of the internal combustion engine.
8 . The method of claim 7 , wherein the confirming that the at least one combustion chamber of the internal combustion engine is clear of fuel comprises measuring at least one of fuel and air in exhaust from the at least one combustion chamber via reading one or more emissions sensors.
9 . The method of claim 1 , further comprising confirming that the at least one combustion chamber is substantially depressurized before the providing the open port to at least one combustion chamber of the internal combustion engine.
10 . The method of claim 9 , wherein the internal combustion engine includes at least one combustion chamber with a reciprocating piston therein; and,
wherein the confirming that the at least one combustion chamber is substantially depressurized comprises determining the position of the reciprocating piston.
11 . The method of claim 9 , wherein the confirming that the at least one combustion chamber is substantially depressurized comprises determining at least one of the piston has not entered a compression stroke, the piston is at the bottom of its stroke, combustion chamber pressure is negative, and combustion chamber pressure is substantially equal to zero.
12 . The method of claim 9 , wherein the confirming that the at least one combustion chamber is sufficiently depressurized comprises at least one of determining the rate of engine spin down and detecting the presence of oscillations associated with chamber pressurizations during engine spin down.
13 . The method of claim 1 , wherein the internal combustion engine includes at least one electrically-controlled exhaust valve; and,
wherein the providing the open port to the at least one combustion chamber of the internal combustion engine comprises opening the at least one electrically-controlled exhaust valve.
14 . The method of claim 1 , wherein the internal combustion engine includes multiple valves that open to form the open port; and,
wherein the providing the open port to the at least one combustion chamber of the internal combustion engine comprises opening all of the valves to provide multiple open ports to multiple combustion chambers.
15 . The method of claim 1 , wherein the internal combustion engine includes multiple valves that open to form the open port, and the multiple valves are at least one of hydraulically opened and solenoid opened.
16 . The method of claim 1 , wherein the providing the open port to at least one combustion chamber comprises providing an open exhaust port to at least one combustion chamber.
17 . The method of claim 15 , wherein the providing the open port to at least one combustion chamber further comprises providing an open intake port to at least one combustion chamber.
18 . The method of claim 1 , wherein the providing the open port to at least one combustion chamber comprises providing an open ignition plug port to at least one combustion chamber.
19 . The method of claim 1 , wherein control of the port is by at least one of one-way communication and two-way communication.
20 . The method of claim 19 , wherein the control is by at least one of the following control protocols: CAN, J1939, and a proprietary communication protocol.
21 . The method of claim 1 , wherein the port is open for all four of the following strokes: intake stroke, compression stroke, power stroke, and exhaust stroke.
22 The method of claim 1 , wherein the hybrid-electric vehicle includes a generator operatively coupled to the internal combustion engine, the method further comprising applying a torque by the generator to the internal combustion engine forcing the internal combustion engine to stop rapidly, in four or less engine rotations.
23 . The method of claim 1 , further comprising force starting the internal combustion engine using a generator to apply a torque to spin the internal combustion engine without engine pressure until rotational speed of the engine reaches a predetermined lower limit.
24 . The method of claim 23 , further comprising:
providing an open port to at least one combustion chamber of the internal combustion engine during force starting until the rotational speed of the engine reaches a predetermined lower limit; and
when the rotational speed of the engine reaches a predetermined lower limit, closing the open port to at least one combustion chamber and starting combustion in at least one combustion chamber.