Abstract: A cover for an automotive vapor canister has a heat-spreading member heated by a self-regulating electrical resistance heater of positive temperature coefficient of resistivity for heating air which is periodically introduced into the canister for purging the canister. The cover has a first cover of thermally insulating material defining a thin inner air flow path section to pass air being introduced into the canister over the heat-spreading member for transferring heat to the air and to receive additional heat within the first cover and has a second cover of thermally insulating material defining a thin outer air flow path section overlying and connected with the inner air flow path section to pass the air over the first cover prior to being advanced into the inner flow path section for withdrawing said additional heat from the first cover to preheat the air and improve air heating efficiency.

Abstract: A thermally actuated valve assembly comprising a housing having a passage extending therethrough with the passage having an inlet, an outlet and a valve seat therebetween. A thermostatic dish-shaped bimetallic disk constituting a valve member is positioned in the passage and is abruptly movable over center from a first curvature position in which the outer periphery of the disk is in engagement with the valve seat thereby to block communication through the passage and a second curvature position in which the disk is clear of the valve seat to permit the flow of fluid therepast. The disk is movable from its first to its second curvature position upon being subjected to a first temperature and is returnable from its second to its first curvature position upon being subjected to a second temperature. A spring member biases the disk toward the valve seat and holds the disk in sealing engagement therewith when the disk is in its first curvature position.