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.
Meaning of DIAPHRAGM in English
English dictionary of automotive terms. Английский словарь автомобильных терминов. 2012