Abstract: A surge reliever relief valve is provided in which a flexible membrane is maintained in a peripherally sealed relationship across a rigid grid. The grid bounds the laterally adjacent intake and output regions of the valve. Intake pressure extends the membrane allowing flow between intake and output. Extension of the membrane is limited by a retainer. Extension may be elastic or inelastic.

Abstract: A surge reliever relief valve is provided in which a flexible membrane is maintained in a peripherally sealed relationship across a rigid grid. The grid bounds the laterally adjacent intake and output regions of the valve. Intake pressure extends the membrane allowing flow between intake and output. Extension of the membrane is limited by a retainer. Extension may be elastic or inelastic.

Abstract: Solar energy collectors, devices and systems utilizing selective solar absorbers for more efficient collection of radiant energy from the sun and its conversion to useful form at relatively high heat transfer temperatures. Each collector unit is made up solely of a closed shell-like enclosure having a continuous, unpenetrated boundary wall evacuated and hermetically sealed to form a structurally strong radiation collecting chamber whose boundary wall surrounds a rarified atmosphere environment such as a vacuum, the wall having a window portion which transmits substantially all of the received solar spectrum to a selective solar radiation absorber in the chamber and energy derived therefrom is collected at any energy collecting and transferring portion of the wall from which heat is conducted to the exterior.