Abstract:
In an internal combustion engine, a linkage is provided between an auxiliary motion source and a main motion load path, such that motions received by the linkage from the auxiliary motion source result in provision of a first force to at least one engine valve and a second force to the main motion load path in a direction toward a main motion source. Where an automatic lash adjuster is associated with the main motion load path, the second force may be selected to aid in the control of lash adjustments made by the automatic lash adjuster. In various embodiments, the linkage may be embodied in an mechanical linkage, whereas in other embodiments, an hydraulic linkage may be employed. The linkage may be incorporated into, or otherwise cooperate, a valve bridge or a rocker arm.
Abstract:
A system for supplying hydraulic fluid in an internal combustion engine comprises a pumping assembly disposed within a housing and a hydraulic circuit, operatively connected to the pumping assembly, also disposed within the housing, which housing may be fixed or dynamic. A source of pumping motions is operatively connected to the pumping assembly, which source of pumping motions may comprise a valve actuation motion source or a component of a valve train between the valve actuation motion source and an engine valve. Pumping motions applied to the pumping assembly by the source of pumping motions causes hydraulic fluid received from a supply pressure hydraulic fluid input of the hydraulic circuit to be transmitted to an increased pressure hydraulic fluid output of the hydraulic circuit.
Abstract:
A system for actuating one or more engine valves comprises a lost motion assembly including locking elements to selectively lock and unlock a locking mechanism disposed within a valve train such that motions may be likewise selectively applied to, or prevented from being applied to, one or more engine valves. In an embodiment, the locking elements comprise wedges having at least one wedge inclined surface defined according to a cone frustum and configured to engage an outer recess formed in a housing, the outer recess comprising an outer recess inclined surface also defined according to the cone frustum. The device may comprise a locking mechanism disposed within a housing bore in the housing and a snubber also disposed in the housing bore. Furthermore, the outer recess may be configured to permit movement of the locking element along a longitudinal axis of the housing bore.
Abstract:
In an internal combustion engine comprising two or more engine valves that receive valve actuation motions from a valve actuation motion source via a valve train, which valve train comprises a hydraulic lash adjuster, an apparatus for valve actuation comprises a valve bridge and a lost motion assembly disposed therein. The lost motion assembly comprises a first piston disposed in a first piston bore formed in the valve bridge. The first piston is configured to operatively connect with a component of the valve train. A biasing element is configured to bias the first piston out of the first piston bore with a first force that is greater than a second force applied to the first piston by the hydraulic lash adjuster. A travel limiter is configured to limit travel of the first piston out of the first piston bore to be no greater than a maximum lost motion distance.
Abstract:
A pushrod assembly for an internal combustion engine comprises a pushrod having a first end and a second end, the first end being configured to receive valve actuation motions from a valve actuation motion source and the second end being configured to impart the valve actuation motions to a valve train component. The pushrod includes a resilient element engagement feature. The pushrod assembly includes a fixed support and a resilient element operatively connected to the resilient element engagement feature and the fixed support. The resilient element is configured to bias the pushrod, via the resilient element engagement feature, toward the valve actuation motion source. An internal combustion engine may comprise the pushrod assembly described herein. A follower assembly may be provided to maintain contact between second end of the pushrod and the valve train component.
Abstract:
Systems for actuating at least two engine valves comprise a valve bridge operatively connected to the at least two engine valves and having a hydraulically-actuated lost motion component. The lost motion component comprises a lost motion check valve disposed therein. A rocker arm has a motion receiving end configured to receive valve actuation motions from a valve actuation motion source and a motion imparting end for conveying the valve actuation motions and hydraulic fluid to the lost motion component. The rocker arm is in fluid communication with a hydraulic fluid supply. The systems also comprise an accumulator in fluid communication with the hydraulic fluid supply and disposed upstream of the lost motion check valve. In all embodiments, a fluid supply check valve may be disposed upstream of the accumulator and configured to prevent flow of hydraulic fluid from the accumulator back to the hydraulic fluid supply.
Abstract:
Systems for actuating at least two engine comprise a valve bridge operatively connected to the at least two engine valves and having a hydraulically-actuated lost motion component. A rocker arm has a motion receiving end configured to receive valve actuation motions from a valve actuation motion source and a motion imparting end for conveying the valve actuation motions and hydraulic fluid to the lost motion component. The motion receiving end is biased toward the valve actuation motion source. A bias mechanism, supported by either the rocker arm, valve bridge or both, is configured to bias the motion receiving end of the rocker arm and the lost motion component into contact with each other. By maintaining such contact, the bias mechanism helps maintain the supply of hydraulic fluid from the rocker arm to the lost motion component.