Variable lost motion valve actuator and method
DCFirst Claim
1. A valve actuation system for controlling the operation of an engine valve, said system comprising:
- means for hydraulically varying the amount of engine valve actuation;
a solenoid actuated trigger valve operatively connected to the means for hydraulically varying; and
means for determining trigger valve actuation and deactuation times based on a selected engine mode, and engine load and engine speed values.
6 Assignments
Litigations
1 Petition
Accused Products
Abstract
A lost motion engine valve actuation system and method of actuating an engine valve are disclosed. The system may comprise a valve train element, a pivoting lever, a control piston, and a hydraulic circuit. The pivoting lever may include a first end for contacting the control piston, a second end for transmitting motion to a valve stem and a means for contacting a valve train element. The amount of lost motion provided by the system may be selected by varying the position of the control piston relative to the pivoting lever. Variation of the control piston position may be carried out by placing the control piston in hydraulic communication with a control trigger valve and one or more accumulators. Actuation of the trigger valve releases hydraulic fluid allowing for adjustment of the control piston position. Means for limiting valve seating velocity, filling the hydraulic circuit upon engine start up, and mechanically locking the control piston/lever for a fixed level of valve actuation are also disclosed.
71 Citations
38 Claims
-
1. A valve actuation system for controlling the operation of an engine valve, said system comprising:
-
means for hydraulically varying the amount of engine valve actuation; a solenoid actuated trigger valve operatively connected to the means for hydraulically varying; and means for determining trigger valve actuation and deactuation times based on a selected engine mode, and engine load and engine speed values. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. A hydraulic valve actuation system for controlling the operation of at least one valve of an engine at different operating temperatures, said valve actuation system including a trigger valve adapted to control hydraulic fluid flow in the valve actuation system, and said valve actuation system comprising:
-
means for determining a present temperature of an engine fluid; means for modifying the operation of the trigger valve in response to the determined temperature; and means for actuating the engine valve responsive to the operation of the trigger valve. - View Dependent Claims (14, 15, 16, 17, 18)
-
-
19. A valve actuation system for controlling the operation of at least one valve of an engine at different engine fluid operating viscosities, said system including a trigger valve for controlling hydraulic fluid flow in the system, and said system comprising:
-
means for determining a present viscosity of an engine fluid; means for modifying the operation of the trigger valve in response to the determined viscosity; and means for actuating the engine valve responsive to the operation of the trigger valve. - View Dependent Claims (20, 21, 22, 23, 24)
-
-
25. A method of modifying the timing of the operation of a trigger valve used to control the actuation of at least one engine valve, said method comprising the steps of:
-
determining a current temperature of an engine fluid; determining a timing modification for the operation of the trigger valve based on the determined current temperature; modifying the timing of the operation of the trigger valve in response to the determined timing modification; and transmitting a valve actuation motion to the engine valve responsive to the operation of the trigger valve. - View Dependent Claims (26, 27, 28, 29, 30, 31)
-
-
32. A method of modifying the timing of the operation of a trigger valve used to control the actuation of at least one engine valve, said method comprising the steps of:
-
determining a current viscosity of an engine fluid; determining a timing modification for the operation of the trigger valve based on the determined current viscosity; and modifying the timing of the operation of the trigger valve in response to the determined timing modification; and transmitting a valve actuation motion to the engine valve responsive to the operation of the trigger valve. - View Dependent Claims (33, 34, 35, 36, 37)
-
-
38. A valve actuation system for compensating for varying engine fluid viscosity by controlling the operation of a trigger valve used to control actuation of at least one valve of an engine, said system comprising:
-
measuring means for determining a present temperature of an engine fluid; measuring means for determining a present viscosity of an engine fluid; control means for modifying the operation of the trigger valve in response to the temperature determined by said temperature measuring means and the viscosity determined by said viscosity measuring means; and operating means for operating the at least one valve responsive to the operation of the trigger valve.
-
Specification