Vacuum limiting, regulating device

Claim 1

In a device for limiting the applied vacuum in a fluid suctioning system, the combination comprising (a) a chamber having an inlet at which a suction level or levels V x is or are to be maintained, and an outlet to which vacuum level V 2 is applied, wherein V x <V 2 , fluid being sucked through said chamber via said inlet and outlet, (b) an annular seat in said chamber, the chamber containing an upstream flow zone R 1 between said inlet and said seat, and a downstream flow zone R 2 between said seat and said outlet, the seat facing longitudinally, (c) and a diaphragm at the upstream side of the seat and extending crosswise thereof and crosswise of at least a portion of said zone R 1 , the diaphragm having a top wall carried for longitudinal movement toward the seat when the vacuum level in R 1 rises to a predetermined level, to reduce or block fluid flow through the chamber, the diaphragm top wall movable away from the seat when the vacuum level in R 1 falls below a predetermined level, (d) the chamber having an outer wall that faces laterally and extends about said seat, (e) said diaphragm consisting of elastomeric material and having a peripheral skirt which extends in a position proximate said outer wall that faces laterally, the diaphragm skirt retained in said position for positioning said diaphragm top wall for said movement toward and away from the seat. (f) the diaphragm top wall substantially everywhere deflected toward the seat by the outer wall when the diaphragm top wall extends furthest from the seat.