Abstract: A housing 10, 12 includes a slide chamber 14 in which a slide bar 30 reciprocates between three positions. A coil spring 60 is carried by the bar and extends into lower and upper recesses 50, 52 in the housing. When the bar is reciprocated from the intermediate position to either of the other positions, the ends of the recesses 54 compress the spring, thereby biasing the bar into the intermediate position.

Abstract: Venting gas flow from a fuel tank or the like enters through tangential inlets into a spin chamber, influencing a closure ball in said chamber to spin or orbit around an upper conical wall portion of the spin chamber. The spinning action keeps the closure ball from seating in an outlet opening formed at the upper end of the spin chamber. The closure ball does seat in response to liquid rising in the spin chamber or tilting of the spin chamber beyond a predetermined angle of tilt. A vibrating mass positioned on the outlet side of the outlet opening includes a central striker portion which contacts the closure ball whenever it tends to seat in response to shock forces or some condition other than the presence of liquid activated buoyancy forces or tilt activated gravity forces.

Abstract: A fuel tank cap (10,130) having a venting valve (56,56A) adapted to relieve pressure and temperature in the tank and prevent spilling fuel from the tank. A cover plate (28,28A) is automatically (34,34A) removed from the cap by excessive temperature so as to allow fluid in the tank to escape. The valve body (56) has a spin chamber (98), having generally circular cross sections (102,104) and at least one tangentially directed side wall inlet opening (106). The chamber cross sections decrease in diameter upwardly of the inlet opening (88) to a point below a circular outlet opening whereby gas venting through the chamber spins a light weight buoyant ball (94) around the chamber so as to prevent the ball from closing during venting. The ball (94) is lifted onto a seat (92) at the outlet to close it when liquid enters the chamber to a predetermined level. A heavy ball (96) in the chamber holds the light ball (94) on the seat when the chamber has been tilted a predetermined amount.