Motor-spring operated valve

Claim 1

IN COMBINATION, A FLUID HOUSING HAVING AN ANNULAR VALVE SEAT THEREIN; A ROTARY VALVE ELEMENT ARRANGED IN THE HOUSING WITH A SURFACE THEREOF MOVABLE BACK AND FORTH ACROSS THE SEAT; A ROTARY STEM ARRANGED IN THE HOUSING SUBSTANTIALLY NORMAL TO THE VALVE SEAT AXIS AND HAVING A DRIVING CONNECTION WITH THE VALVE ELEMENT WHICH PRECLUDES RELATIVE ROTATION BETWEEN THE STEM AND ELEMENT BUT WHICH PERMITS FREE MOVEMENT OF THE ELEMENT RADIALLY OF THE STEM; AN ABUTMENT FIXED ON ONE OF SAID HOUSING AND VALVE ELEMENT AND A SPRING MEMBER CARRIED BY THE OTHER OF SAID HOUSING AND VALVE ELEMENT IN SPACED REGISTRY WITH THE ABUTMENT SO THAT DURING ROTARY MOVEMENT OF THE ELEMENT TOWARD THE CLOSED POSITION THE SPRING MEMBER AND ABUTMENT STRIKE ONE ANOTHER TO THEREBY PROPEL THE VALVE ELEMENT RADIALLY OF THE STEM TOWARD A TIGHT ENGAGEMENT WITH THE VALVE SEAT.