| 摘要 |
An electronic variable orifice tube (16) suitable for use as an expansion valve in a refrigeration system (10) providing two flow rates in response to electronic control signals comprises a bodytube (26), a restrictor (40) mounted within the bodytube and defining a first (42) flowpath. A plunger (54) is translatably positioned within the bodytube (26) in proximity to the restrictor (40) and defines a second (56) and a third (58) flowpath. A valve actuator (28) is functionally coupled to the plunger (54) to translate the plunger within the bodytube (26) to transition between the two flow rates. A high flowpath is formed through the bodytube by the first (42), second (56), and third (58) flowpaths, and a low flowpath is formed through the bodytube by the first (42) and the second (56) flowpaths to the exclusion of the third (58) flowpath. A solenoid (30) may be used as valve actuator and a spring (50) may be employed to return the plunger (54) to its quiescent state when the solenoid (30) is not energized. |
