摘要 |
A pneumatic conveying system includes a conveying conduit, a gas conduit which communicates with it at least at one juncture, and a release valve at the juncture. The release valve includes a housing connected with the conveying conduit and the gas conduit, a flexible diaphragm secured to the housing and subdividing the same into one chamber communicating with the gas conduit and another chamber connected with the conveying conduit, the diaphragm having a substantially central opening, a valve-seat member connected to and movable with the diaphragm in response to flexing of the same and forming a valve seat surrounding the opening, a valve member carried by the housing and located in the one chamber, means guiding the valve seat member for movement relative to the valve member between a valve-opening and a valve-closing position, and valve-closing spring means located in the one chamber and permanently tending to urge the valve-seat member to the valve-closing position thereof. |