An expansion valve comprising a stop element

摘要

An expansion valve (1) for a vapour compression system, the valve (1) comprising a first valve part (5) having an outlet orifice (7) and a piston (8) movable inside the outlet orifice (7) in response to a differential pressure across the expansion valve (1), controlling a fluid flow through the valve (1). The piston (8) comprises a stop element (9) at an outlet end (8b) of the piston (8) and mechanical forcing means (10) to force the piston (8) towards a position in which the stop element (9) is brought into abutment with a valve seat (12) of the first valve part (5). A differential pressure below a predefined threshold value causes the stop element (9) of the piston (8) to abut the valve seat (12) of the first valve part (5), preventing fluid flow through the first valve part (5), via the forward fluid passage.