US 7,581,710 B2 · Thermally isolated actuator with temporary contacting linkage for an exhaust valve

Abstract

An exhaust valve assembly includes a valve body, a valve supported by a shaft within the valve body, and an actuator that moves the valve relative to the valve body to control exhaust flow. The actuator is thermally isolated from the valve by a linkage mechanism that cooperates with exhaust flow to move the valve between open and closed positions. The actuator temporarily contacts the linkage mechanism to initiate opening and closing movement but then moves out of contact with the linkage mechanism as the exhaust flow exerts a force against the valve to move the valve to a fully open or fully closed position. This temporary contact between the linkage mechanism and the actuator reduces heat transfer from the valve to the actuator.

Claims20

Dependent claims

An exhaust valve assembly comprising:

a valve body;
a valve supported on a valve shaft for movement within said valve body;
an actuator that moves said valve within said valve body between an open position and a closed position;
and
a linkage mechanism coupled to said valve shaft wherein said actuator contacts said linkage mechanism to initiate opening and closing movement of said valve and subsequently moves out of contact with said linkage mechanism to thermally isolate said actuator from said valve as exhaust flow continues to move said valve to one of the open or closed positions, and wherein said linkage comprises a valve gear having at least a first tooth and a second tooth, said actuator temporarily contacting said first tooth to initiate opening movement and temporarily contacting said second tooth to initiate closing movement.

2 more elements

A method for moving an exhaust valve assembly between an open position and a closed position comprising the steps of:

(a) providing a valve body, a valve supported on a valve shaft for movement within the valve body, an actuator for controlling movement of the valve, and a linkage mechanism coupled to the valve shaft and wherein the linkage mechanism includes a valve gear having at least a first tooth and a second tooth that pivot about a valve axis, and the actuator includes an arm that pivots about an actuator axis;
(b) contacting the linkage mechanism with the actuator to initiate one of opening and closing movement of the valve including temporarily contacting the first tooth with the arm to initiate opening movement, and temporarily contacting the second tooth with the arm to initiate closing movement;
and
(c) subsequently moving the actuator out of contact with the linkage mechanism to thermally isolate the actuator from the valve as exhaust flow continues to move the valve to one of the open and closed positions.

1 more element

Dependencies are inferred from the claim text.

Thermally isolated actuator with temporary contacting linkage for an exhaust valve

Life of this patent

Thermally isolated actuator with temporary contacting linkage for an exhaust valve

Life of this patent

Abstract

Claims20