Over-center actuator
AssigneeSiemens VDO Automotive Corporation
InventorPhilip Stuart
Life of this patent
Estimating the term…
Abstract
The disclosure allows a short runner valve or manifold tuning valve type manifold tuning device to retain sufficient force on the valve assembly in its closed state to eliminate any vibration or chatter from the system under normal engine operation. The disclosure also allows the device to be “pulsed” to the open or closed position; thus no electrical power is required to keep the system in one state. This is especially useful if activated times are extended due to certain engine operating conditions.
Claims14
An actuator comprising:
- an operator for moving an actuating member in one direction to move an actuated member to one travel limit and in an opposite direction to move the actuated member to an opposite travel limit;
- and
- an over-center spring mechanism for imparting to the actuating member a spring pre-load force that, with the actuated member at the one travel limit, forces the actuated member in the one direction against a limit stop that defines the one travel limit.
An intake system in an internal combustion engine comprising:
- a tuning mechanism for tuning the intake system by selectively positioning a valve mechanism comprising one or more valves in the intake system;
- an operator for operating the valve mechanism to selectively position the one or more valves;
- an actuating member through which the operator operates the valve mechanism, wherein the operator moves the actuating member in one direction for positioning the one or more valves to a closed position defined by a limit stop and in an opposite direction for positioning the one or more valves to an open position;
- and
- an over-center spring mechanism for imparting to the actuating member a spring pre-load force that, with the one or more valves in closed position, forces the valve mechanism against the limit stop.
A method of attenuating chatter in a tuning mechanism that tunes an internal combustion engine intake system by selective positioning of a valve mechanism that has one or more valves in the intake system, the method comprising:
- electrically energizing a device to apply a force to an actuating member in one direction for causing the valve mechanism to move the one or more valves from an open position toward a closed position defined by a limit stop;
- as the actuating member is moving over an initial span of travel, increasingly compressing a mechanical spring in an over-center spring mechanism that is associated with the actuating member until the actuating member has been moved far enough to cause the over-center spring mechanism to go over center;
- and
- as the actuating member is moving over a final span of travel after the over-center spring mechanism has gone over center, allowing the spring to release energy imparted to it as it was being increasingly compressed, and once the one or more valves are in closed position, maintain a pre-load force on the valve mechanism that is reacted by the limit stop.
Dependencies are inferred from the claim text.