2931results about "Valve drives" patented technology

The disclosure relates to fluid working devices including reciprocating internal combustion engines, compressors and pumps. A number of arrangements for pistons and cylinders of unconventional configuration are described, mostly intended for use in reciprocating internal combustion IC engines operating without cooling. Included are toroidal combustion or working chambers, some with fluid flow through the core of the toroid, pistons reciprocating between pairs of working chambers, tensile valve actuation, tensile links between piston and crankshaft, energy absorbing piston-crank links, crankshafts supported on gas bearings, cylinders rotating in housings, injectors having components reciprocate or rotate during fuel delivery. In some embodiments pistons mare rotate while reciprocating. High temperature exhaust emissions systems are described, including those containing filamentary material, as are procedures for reducing emissions during cold start by means of valves at reaction volume exit. Compound engines having the new engines as a reciprocating stage are described. Improved vehicles, aircraft, marine craft and transmissions adapted to receive or be linked to the improved IV engines are also disclosed.

In a control apparatus for controlling a variable valve actuation system employed in an internal combustion engine, engine/vehicle sensors are provided to detect at least a cylinder pressure in an engine cylinder for monitoring a change of state in combustion, arising from fluctuations in states/characteristics of air-fuel mixture such as a change in fuel property. Also provided is a control system that controls the variable valve actuation system responsively to a manipulated variable modified based on the cylinder pressure reflecting the change of state in combustion by a model of combustion.

Lost motion systems and methods for providing engine valves with variable valve actuation for engine valve events are disclosed. The system may include a master piston hydraulically linked to a slave piston, and a dedicated cam operatively connected to the master piston. The slave piston may be disposed substantially perpendicular to the master piston in a common housing. The slave piston is adapted to actuate one or more engine valves. The slave piston may incorporate an optional valve seating assembly into its upper end. A trigger valve may be operatively connected to the master-slave hydraulic circuit to selectively release and add hydraulic fluid to the circuit.

A method for improving efficiency and reducing emissions of an internal combustion engine. Variable displacement engine capabilities are achieved by disabling engine valves during load changes and constant load operations. Active cylinders may be operated at minimum BSFC by intermittently disabling other cylinders to provide the desired net torque. Disabling is begun by early closing of the intake valve to provide a vacuum at BDC which will result in no net gas flow across the piston rings, and minimum loss of compression energy in the disabled cylinder; this saving in engine friction losses is significant with multiple disablements.

A valvetrain system mechanization for an internal combustion engine using compression ignition, including homogeneous charge compression ignition, having two intake and one or more exhaust valves per cylinder. The valves are operated by dual overhead camshafts having two-step cams. The intake and exhaust camshafts are provided with phasers for varying the opening and closing of the intake and exhaust valves. A two-step roller finger follower is disposed for each valve between the cam lobes and the valve stem. The two sets of intake and exhaust valves are controlled by separate oil control valves. Swirl of gases may be introduced by mismatching the lifts of the valves. The valve opening times, closing times, lifts, fuel injection, compression ratio, and exhaust gas recirculation may be varied to optimize combustion conditions for a range of engine operating modes.

A required valve timing change rate Vreq is calculated so as to make a deviation D between a target valve timing VTtg and an actual valve timing VT small and then a required speed difference DMCRreq between a motor 26 and a camshaft 16 is calculated on a basis of the required valve timing change rate Vreq. When the deviation D is larger than a predetermined value, a required motor speed Rmreq is calculated by adding the required speed difference DMCRreq to a camshaft speed RC and a motor control value is calculated so as to control the motor speed RM to the required motor speed Rmreq. When the deviation D is not larger than the predetermined value, the camshaft speed RC is set as the required motor speed Rmreq and the motor control value is calculated so as to control the motor speed RM to the camshaft speed RC.

An apparatus for adjusting the stroke of a valve that is actuated by a camshaft having at least one cam is provided. A valve lever having an outer lever and an inner lever is provided and has a first end region supported on a fixed component, and a second end region for actuating a valve. The U-shaped outer lever includes two arms and a crosspiece that faces the fixed component. At least one of the arms is provided with an abutment surface for contacting the at least one cam. The inner lever is mounted on a free end of the outer lever between the arms, and has an abutment surface, for contacting cams, that is disposed between the mounting axis of the inner lever on the arms and the support of the first end region of the valve lever on the fixed component. A blocking device is provided for fixing the crosspiece of the outer lever on an end of the inner lever remote from the valve, this end being supported on the fixed component and containing the blocking device.

A valve control system including a camshaft having first and second cam profiles, the valve control system comprising a rocker arm assembly (11) including a first rocker arm (13) having a first cam follower (15) in engagement with the first cam profile, and a second rocker arm (17) having a second cam follower (23,25) in engagement with the second cam profile. The engine includes a fulcrum location (P) operable to provide a source of pressurized fluid, and the first rocker arm includes a latch member (47) moveable between latched (FIG. 6) and unlatched conditions. The latch member is biased toward the latched condition by a fluid pressure in a chamber (51), and the first rocker arm defines a fluid passage (55) having a first end (57) in open fluid communication with the pressure source, and a second end (59) in open fluid communication with the pressure chamber (51).

A twin vane-type phaser is described which is provided with a locking mechanism for locking the drive member to the driven members when the pressure in the working chambers is a below is predetermined value. The locking mechanism comprises two coaxial locking pins 114, 118 mounted in a common bore 110 in the centrally located member 32. The locking pins are resiliently urged apart by a spring 120 into bores in the two outer members 38, 40 and are retracted by pistons 112, 116 when the hydraulic pressure in the working chambers attains the predetermined value.

A mode-switching cam follower is disclosed, wherein the follower includes a body, a cam contact movably coupled to the body, a latch member movably coupled to the body, wherein the latch member is movable between a coupled position in which the cam contact is held in a fixed relation to the body by the latch member and a decoupled position in which the cam contact is decoupled from the latch member and movable relative to the body, and an actuator in communication with the latch member, wherein the actuator comprises a shape memory alloy member

Apparatus and method are disclosed for converting an internal combustion engine from a normal engine operation (20) to an engine braking operation (10). The engine includes exhaust valve train components comprising at least one exhaust valve (300) and at least one cam (230) for cyclically opening and closing the at least one exhaust valve (300). The apparatus comprises actuation means (100) having at least one component integrated into at least one of the exhaust valve train components, such as a rocker arm (210) or a valve bridge (400). The actuation means (100) has an inoperative position and an operative position. In the inoperative position, the actuation means (100) is retracted and the small braking cam lobes (232&233) are skipped to generate a main valve lift profile (220m) for the normal engine operation (20). In the operative position, the actuation means (100) is extended to form a mechanical linkage so that the motion from all the cam lobes (220, 232&233) is transmitted to the at least one exhaust valve (300) for the engine braking operation (10). The apparatus further comprises control means (50) for moving the actuation means (100) between the inoperative position and the operative position to achieve the conversion between the normal engine operation (20) and the engine braking operation (10). The apparatus also includes valve lash adjusting mechanism, oil retraining means (350), and engine brake reset means (150).

A variable camshaft timing phaser for an internal combustion engine having at least one camshaft comprising a plurality of vanes in chambers defined by a housing and a spool valve. The vanes define an advance and a retard chamber. At least one of the vanes is cam torque actuated (CTA) and at least one of the other vanes is oil pressure actuated (OPA). The spool valve is coupled to the advance and retard chamber defined by the CTA vane and the advance chamber defined by the OPA vane. When the phaser is in the advance position, fluid is routed from the retard chamber defined by the OPA vane to the retard chamber defined the CTA vane. When the phaser is in the retard position, fluid is routed from the retard chamber defined by the CTA vane to the advance chamber defined by the CTA vane.

Systems and methods for actuating engine valves are disclosed. The systems may include a rocker arm having an adjustable length push tube mounted to a first end and multiple contact surfaces for an engine valve bridge at a second end. An actuator piston assembly may be provided in the rocker arm between the first and second rocker arm ends. The actuator piston assembly is adapted to extend from the rocker arm under the influence of hydraulic pressure and actuate an inboard engine valve through the engine valve bridge when an actuator piston is locked into an extended position.

A variable valve actuation system for providing discrete exhaust and intake valve lift profiles for various operating modes of an internal combustion engine. The variable valve actuation system includes exhaust and intake rocker assemblies, exhaust and intake hydraulic extension devices operatively coupling corresponding rocker assemblies with respective engine valves and exhaust and intake control valves for selectively supplying the pressurized hydraulic fluid to the extension devices so as to independently switch them between a pressurized condition and a depressurized condition. The engine further includes an exhaust brake provided to initiate a small lift of the exhaust valve during the engine braking operation while the exhaust extension device maintains the exhaust valve open during a compression stroke for bleeder-compression release braking. The exhaust and intake valves can be adjusted independently to provide combinations of valve lift modes.

An infinitely variable cam indexer utilizes engine oil pressure to actuate a cam and preferably uses an inlet check valve in the oil source to minimize back flow during a torque reversal. The control system is in the center of the rotor and uses an electromechanical actuator, preferably a variable force solenoid, acting directly on the spool to control oil flow. This design reduces leakage and improves the response of the phaser. There are shorter oil passages as compared to a control system mounted at the cam bearing.

An expansible chamber pneumatic system, for example a fluid pump system, includes two or more double-acting diaphragm pumps, each with symmetrical left and right pump housings, each housing including an air chamber and a fluid chamber separated by a movable diaphragm. The diaphragms are connected for reciprocating movement in unison to pump fluid through their respective fluid chambers. Each pump includes an air valve actuated by Control air to direct Process air into one of the air chambers, simultaneously releasing used Process air from the other air chamber to thereby move the diaphragms, thereby to pump fluid. A pilot valve directs Control air to the air valve to position the air valve. The pilot valve is responsive to diaphragms reaching their travel limit in one direction to direct Control air to reverse the directions of Process air flow through the air valve to thereby reverse the movement of the pump diaphragms. Control air exhausts through the pilot valve to atmosphere. Process air exhausts through the air valve from one pump to become input or motive air for the next pump.

A turbine (2) driven electric power production system (1), —said turbine (2) arranged for being driven by a fluid (3) having a fluid speed (v) varying in time, —said turbine (2) connected to a hydrostatic displacement pump (6) further connected to a hydrostatic displacement motor (8) as part of a closed loop hydrostatic transmission system (7), —said motor (8) arranged for driving an electrical generator (9) supplying AC power (10) at a frequency (f_g) near a given desired frequency (f_des), characterized by a closed loop system arranged for controlling a volumetric displacement (13) of the hydrostatic motor (8), comprising —a fluid speed meter (11m) arranged for producing a speed signal (11s) representing a speed (v) of said fluid (3), and —a rotational speed meter (12m) arranged for providing a rotational speed signal (12s) representing a rotational speed measurement (ω) of said turbine (2), —a motor displacement control system (15) for continuously receiving said speed signal (11s) and said rotational speed signal (12s) and arranged for calculating a control signal (16), —a volumetric displacement control actuator (17) on said hydrostatic motor, arranged for receiving said control signal (16) for continuously adjusting a volumetric displacement (d) of said hydrostatic motor (8) for maintaining a set turbine tip speed ratio (tsr_set) and thereby providing an improved power efficiency of the power production system (1) during fluctuations in said fluid speed (v).

A device for adjusting the phase angle of a camshaft of an internal combustion engine includes an adjusting mechanism which is operated by an electric motor, the latter being rigidly connected to the camshaft or the camshaft drive gear. Reliable adjustment is obtained in a simple manner by providing the adjusting mechanism as a planetary gear set.