摘要:
A system for actuating at least two engine valves comprises a first rocker assembly operatively connected to a first valve actuation motion source and to a first engine valve. The first rocker assembly comprises a first lost motion component arranged in series with a first input rocker and a first output rocker. A second rocker assembly is operatively connected to a second valve actuation motion source and to a second engine valve. The second rocker assembly comprises at least one second rocker. The system further comprises a one-way coupling mechanism disposed between the first output rocker and the at least one second rocker such that second valve actuation motions are transferred from the at least one second rocker to the first output rocker, and first valve actuation motions are not transferred from the first output rocker to the at least one second rocker.
摘要:
A system for controlling actuation of an engine valve comprises a pivot and a torsion spring having first and second legs operatively connected to the pivot. A lever arm is adjustably affixed to and extending away from the pivot, and is further rotatable about a pivot axis of the pivot between a retracted position and an extended position and vice versa relative to a motion conveying component. Furthermore, a housing is provided having a pivot bore formed therein with the pivot rotatably disposed in the pivot bore. The housing further comprises a first and second openings intersecting with the pivot bore such that the first and second legs extend out of the first opening and the lever arm extends out of the second opening. When a first force is applied by the motion conveying component to the lever arm, such first force maintains the lever arm in the extended position.
摘要:
Systems and methods for controlling valves in valve actuation systems in internal combustion engines systems may be particularly suitable for sequencing valve motion in engine environments that combine cylinder deactivation and high-power density (HPD) engine braking. A main event motion system is configured to produce main event motion in one or more valve sets. An engine braking system produces engine braking motion and a cylinder deactivation system selectively deactivates main event motion of the intake and exhaust valves the valve set. A blocking system selectively prevents the cylinder deactivation system from deactivating main event motion of at least one intake valve during the engine braking operation. Thus, main event intake valve motions may be available for braking operations, such as HPD braking where main event intake valve motion may be used to enhance CR braking. One actuator can control deactivation of paired intake and exhaust main event motion.
摘要:
A valve actuation system comprises a first arm having a first arm contact surface and operatively connected to a valve actuation motion. A second arm having a second arm contact surface is operatively connected to the at least one engine valve. A discrete lost motion device is provided that is controllable between a first, motion conveying state and a second, motion absorbing state. The discrete lost motion devices comprises a plunger contact surface and a housing contact surface. The housing contact surface is configured to engage one of the first or second arm contact surfaces, and the plunger contact surface is configured to engage another of the first and the second arm contact surfaces. The first and second arm contact surfaces, the housing contact surface and the first plunger contact surface are configured to support the discrete lost motion device between the first arm and the second arm.
摘要:
A switching finger may operate in two or three states or positions and cooperate with a single motion source to achieve methods of operating an engine in corresponding two or three modes. The modes may include cylinder deactivation, main event or auxiliary modes, including lost motion braking, LIVC and EEVO. A follower for an engine valve train utilizes an adjustable support assembly that eliminates potential for partial engagement during operation. A lever engagement member or latch is disposed for movement on the follower body and interacts with a lever to provide a constant contact geometry. The latch may support the lever in one or more precise positions, or permit the lever to pivot free of the latch for complete lost motion, as in cylinder deactivation applications.
摘要:
Control of engine shutdown of an internal combustion engine comprising a plurality of cylinders and, for each of the plurality of cylinders, a hydraulically controlled lost motion component operatively connected to an engine valve corresponding to the cylinder, is achieved when an engine controller determines that shutdown of the internal combustion engine has been requested. Responsive to the request for shutdown, the engine controller initiates or continues cylinder deactivation operation for each of at least one cylinder of the plurality of cylinders. The initiation or continuation of the cylinder deactivation operation for each of the at least one cylinder comprises, for an input to the hydraulically controlled lost motion component for each of at least one engine valve corresponding to the cylinder, operating the input to provide the cylinder deactivation operation for a duration at least long enough to complete shutdown of the internal combustion engine.
摘要:
A switching finger follower for an engine valve train utilizes an adjustable support assembly that eliminates potential for partial engagement during operation. A lever engagement member or latch is disposed for movement on the follower body and interacts with a lever to provide a constant contact geometry. The finger follower may be configured as a lost motion device and may include a biasing assembly and a travel limiter. The latch may support the lever in at least one precise position and may support the lever in a second position for partial lost motion, or permit the lever to pivot free of the latch for complete lost motion, as in cylinder deactivation applications.
摘要:
A third motion transfer mechanism transfers valve actuation motion from a second motion source to a first engine valve. A motion decoupler is configured to selectively discontinue the transfer of motion from a first motion transfer mechanism to the first engine valve. Furthermore, a reset mechanism is configured to selectively discontinue, based on operation of a second motion transfer mechanism, the transfer of motion from the third motion transfer mechanism to the first engine valve. The third motion transfer mechanism may comprise a master piston and a slave piston in fluid communication with each other via a hydraulic circuit, the master piston being configured to receive motion from the second motion source and the slave piston being configured to transfer motion to the first engine valve.