Back to results
US 9,752,470 B2Granted
Applied-ignition internal combustion engine with variable valve drive
AssigneeFord Global Technologies, LLC
InventorsBas Lambertus van den Heuvel, Wilbert Hemink, Richard Fritsche, Claudia Conee, Werner Willems, Franz Arnd Sommerhoff, Christian Hans
Life of this patent
Estimating the term…
Abstract
A system and method is provided for an at least partially variable valve drive in an internal combustion engine. In one example, the at least partially variable valve drive comprises a hydraulically adjustable actuating device which may be charged with pressurized oil via an oil pressure line which branches off from an oil circuit.
Claims20
An applied-ignition internal combustion engine comprising:
- at least one cylinder head with at least one cylinder, each cylinder having at least two inlet openings for the supply of fresh air via an intake system and/or at least two outlet openings for the discharge of exhaust gases via an exhaust-gas discharge system;
- a first pump for supplying engine oil to the internal combustion engine, thus forming a first oil circuit;
- at least two at least partially variable valve drives having at least two valves which are movable between a valve closed position and a valve open position in order to open up and block the at least two inlet or outlet openings of a cylinder, having valve spring means for preloading the valves in a direction of the valve closed position, and having at least two hydraulically adjustable actuating devices arranged in a second oil circuit for opening the valves counter to a preload force of the valve spring means, each actuating device comprising a cam which is arranged on a camshaft and which, as the camshaft rotates, can be brought into engagement with at least one cam follower element, whereby the associated valve can be actuated;
- a second oil pump arranged in the second oil circuit upstream of the actuating devices;
- and
- a solenoid valve separating the first oil circuit from the second oil circuit, the solenoid valve arranged directly upstream from the second oil pump,
- wherein each hydraulically adjustable actuating device can be charged with pressurized oil via an oil pressure line which branches off from the second oil circuit downstream of the second pump, there being arranged in the oil pressure line a controllable shut-off element which blocks or opens up the oil pressure line, and
- wherein the cams of the at least two hydraulically adjustable actuating devices of the at least two at least partially variable valve drives are rotatable.
5 more elements
A method for operating an engine, comprising:
- operating a first pump to supply engine oil to a first oil circuit;
- determining a target intake and/or exhaust valve timing and lift based on engine operating conditions;
- determining an oil pressure required in an oil infeed line for target valve timing, the oil infeed line arranged in a second oil circuit downstream of a solenoid valve and upstream of a second pump, the first and second oil circuits separated by the solenoid valve;
- determining an oil pressure required in an oil pressure line based on the determined target lift, the oil pressure line arranged in the second oil circuit downstream of the second pump and having a controllable shut-off element arranged therein;
- actuating the solenoid valve and the second pump to provide the determined oil pressure required in the oil infeed line;
- and
- actuating the shut-off element to provide the determined oil pressure required in the oil pressure line.
4 more elements
A method for operating an engine, comprising:
- operating a first pump to supply engine oil to a first oil circuit;
- determining a target intake and/or exhaust valve timing and lift based on engine operating conditions;
- determining an oil pressure required in an oil infeed line for target valve timing, the oil infeed line arranged in a second oil circuit downstream of a solenoid valve and upstream of a second pump, the first and second oil circuits separated by the solenoid valve;
- determining an oil pressure required in a separate oil pressure line branching from an oil pressure line for target valve lift, the oil pressure line arranged in the second oil circuit downstream of the second pump and upstream of a cam-in-cam camshaft, the separate oil pressure line branching from the oil pressure downstream of the camshaft and having a controllable shut-off element arranged therein, the separate oil pressure line fluidly communicating with a switchable rocker arm of a hydraulically adjustable actuating device downstream of the shut-off element;
- actuating the solenoid valve and the second pump to provide the determined oil pressure required in the oil infeed line;
- and
- actuating the shut-off element to provide the determined oil pressure required in the separate oil pressure line.
4 more elements
Dependencies are inferred from the claim text.