Flexible diaphragm operated valve structure

Claim 1

IN A DIAPHRAGM ASSEMBLY FOR USE IN A VALVE STRUCTURE: A FLEXIBLE DIAPHRAGM HAVING A PERIPHERAL PORTION; AND A VALVE BODY HAVING PARTS FORMING SUBSTANTIALLY OPPOSED KNIFE-LIKE EDGES BETWEEN WHICH THE PERIPHERAL PORTION OF THE DIAPHRAGM IS RECEIVED, SAID DIAPHRAGM HAVING FREE PERIPHERAL EDGES PROJECTING BEYOND SAID KNIFE-LIKE EDGES, SAID KNIFE-LIKE EDGES BEING SPACED FROM EACH OTHER AN AMOUNT RELATIVE TO THE THICKNESS OF THE DIAPHRAGM TO PERMIT THE PERIPHERAL PORTION OF THE DIAPHRAGM TO SLIDE INWARDLY AND OUTWARDLY IN A GENERALLY RADIAL DIRECTION PAST SAID KNIFE-LIKE EDGES AS THE DIAPHRAM IS FLEXED, WHILE CONFINING THE AREA OF THE DIAPHRAGM AT SAID KNIFE-LIKE EDGES AGAINST AXIAL MOVEMENT WITH THE CENTER OF THE DIAPHRAGM, SAID KNIFE-LIKE EDGES BEING FORMED TO PROVIDE A RESTRICTED AREA OF ENGAGEMENT WITH THE DIAPHRAGM.