Patent ID: 7678177

Claim:
A membrane air dryer for removing moisture from compressed air, comprising: an elongate shell at least partially enclosing a membrane assembly having a tubular configuration extending along the length of the shell; a sweep valve housing at one end of the shell and supporting a sweep valve; the sweep valve including a fixed valve element on the housing; the sweep valve also including a movable valve element supported on the housing for movement relative to the fixed valve element in a direction transverse to the length of the shell, the movable valve element being oriented relative to the shell so that the movable element is moved by gravity into a closed position; the movable valve element being movable against the gravity in response to a flow of dried air from the membrane assembly to enable flow of a first portion of the dried air to a delivery port of the air dyer and flow of a second portion of the dried air to a sweep chamber as sweep air for the membrane assembly.