Diaphragm

[1] A flexible cloth-rubber sheet that is stretched across an area thereby separating two different compartments. A diaphragm is used in pumps to create a pressure differential that causes a fluid to be pushed or pulled from one point to another. Some carburetors have no float bowl (i.e., Tillotsen), but use a series of diaphragms to pump gasoline into the engine.
[2] A flexible partition used to separate two chambers or elements.
[3] In air-conditioning system, a rubber-like piston or bellows assembly which divides the inner and outer chambers of backpressure regulated air conditioning devices.
[4] In fuel system, a thin dividing sheet or partition which separates a housing into two chambers, one of which is usually vented to vacuum while the other is not; used in vacuum-controlled secondaries, anti-stall dashpots, and other carburetor control devices.
See also piston diaphragm
[5] A rubber-like piston or bellows assembly which divides the inner and outer chambers of back-pressure regulated air conditioning devices,