A flow control structure which is primarily intended to be utilized as a pressure compensating emitter in agricultural watering or irrigation can be constructed utilizing a housing having a flow control member located therein. The housing employed has an internal cylinder connected by a passage leading to a valve seat. The flow control member extends from the cylinder to adjacent to the valve seat. The extremity of the flow control member within the cylinder is formed as a piston so that the flow control member may be moved by fluid pressure. A channel means connects this first extremity of the flow control member with the interior of the passage at a point which is adjacent to and spaced from the other extremity of the flow control member. This other extremity is shaped so as to cooperate with the valve seat in order to limit flow between this other extremity and the valve seat in accordance with the position of the flow control member.
A valve arrangement for a variable displacement refrigerant compressor comprising one or more valve assemblies adapted to regulate fluid communication between the compressor's discharge cavity and the interior of the crankcase as a function of a predetermined fluid pressure differential. The valve assemblies operate to modulate, as a function of the ambient temperature, the set point of the compressor thereby avoiding evaporator freeze up.
