Patent ID: 7975481

Claim:
A steam cycle apparatus, comprising: a reservoir for a liquid operating medium; an evaporator in which liquid operating medium is evaporated by the supply of heat thereto; an expander to which the vaporous operating medium is supplied for expansion and for performing mechanical work; a condenser to which the operating medium is then supplied for liquefaction, the condenser fluidly connected to the reservoir; an operating medium pump for supplying operating medium from the reservoir to a feed line fluidly connected to the reservoir, a bypass line forming a connection between input and output sides of the operating medium pump; a feedback control unit for operating medium flow; an externally controlled pressure-limiting overflow valve arranged in the bypass line and having a control element controlled by the feedback control unit for regulating pressure and/or volume flow of the operating medium in the feed line to the evaporator; and a pressure-reducing valve externally controlled by means of an electromagnetic control unit, the control element of the externally controlled pressure-limiting overflow valve subjected to a control pressure by the pressure reducing valve.