Patent ID: 9004241
Filing Date: 2015-04-14
Classification: B60T,F16D

Abstract:
1. A vehicle-mounted device for delivering cooling air, on demand, to a vehicle brake, the device comprising: a duct with an inlet, the inlet being positioned on a vehicle to access an air flow passing around a vehicle exterior, and the duct and inlet cooperating to transport air from the vehicle exterior of a forward-moving vehicle to one or more vehicle brakes; a closure located in the duct or inlet, the closure denying passage of cooling air in a closed position and allowing passage of cooling air in an open position; and a rotary actuator, comprising two, generally straight, linear shape memory alloy (SMA) elements, a fixed support and a pivotable body, the pivotable body being attached, at its center, to a shaft operably connected to the closure, each of the shape memory alloy elements being of like length and cross-section, and being adapted for Joule heating by passage of electric current along their lengths; the SMA elements having first and second ends, the first ends of each SMA element being attached to the fixed support and the second ends of each SMA element being attached to opposing connection points on the pivotable body so that alternately heating one of the SMA elements will contract the heated SMA element and rotate the body about its center, and stretch the unheated SMA element, so that alternately heating each of the SMA elements will transition the closure between its open and closed positions; and, the actuator further comprising at least one releasable mechanical retainer adapted to engage the pivotable body and so maintain the closure in each of its open or closed positions upon ceasing passage of current through the heated element, the releasable mechanical retainer being further adapted to disengage from the pivotable body to enable rotation of the pivotable body when the unheated SMA element is subsequently heated by passage of electric current and contracts.