초록 ▼

A pulse controlled refrigeration expansion valve and method of controlling the valve is disclosed. The valve is preferably an on/off (open/closed) direct controlled solenoid valve. The valve is periodically energized (opened) and de-energized (closed) in response to a refrigeration system parameter

A pulse controlled refrigeration expansion valve and method of controlling the valve is disclosed. The valve is preferably an on/off (open/closed) direct controlled solenoid valve. The valve is periodically energized (opened) and de-energized (closed) in response to a refrigeration system parameter (e.g., superheat) such that the ratio of energization time/de-energization time during each period of operation of the valve is varied in response to the system parameter(s) and such that the on/off solenoid valve functions as a modulated refrigerant flow control expansion valve.

대표청구항 ▼

Apparatus for controlling a refrigeration system, the latter comprising a compressor having an inlet and an outlet, a condenser connected to the outlet of the compressor, an evaporator connected to said condenser and to the inlet of said compressor, an expansion valve between said condenser and said

Apparatus for controlling a refrigeration system, the latter comprising a compressor having an inlet and an outlet, a condenser connected to the outlet of the compressor, an evaporator connected to said condenser and to the inlet of said compressor, an expansion valve between said condenser and said evaparator, said condenser delivering high pressure liquid refrigerant to said expansion valve, said apparatus comprising a solenoid valve constituting said expansion valve, said solenoid valve having a valve body with a flow passage therewithin for the flow of refrigerant therethrough, a valve seat constituting a portion of said flow passage, a valve member selectively movable between a closed position in which it is sealingly engageable with said valve seat so as to block the flow of refrigerant through said flow passage and an open position in which said valve member is clear of said valve seat permitting the flow of refrigerant through said flow passage, said flow passage downstream from said valve seat having a metering orifice therein for restricting the flow of refrigerant through said flow passage to a predetermined flow rate when said valve member is open substantially independently of the distance said valve member is moved from its closed position, a solenoid actuator for effecting movement of said valve member between its closed and its open position upon energization and de-energization of said solenoid actuator, a spring for resiliently biasing said valve member toward one of its said positions, and control means for periodically energizing and de-energizing said solenoid actuator thereby to regulate the flow of refrigerant through said solenoid valve. In a refrigeration system comprising a compressor having an inlet and an outlet, a condenser connected to the outlet of the compressor, an evaporator connected to said condenser and to the inlet of said compressor, an expansion valve between said condenser and said evaporator, said condenser delivering high pressure liquid refrigerant to said expansion valve, said refrigerant expanding as it flows through said expansion valve, wherein the improvement of this invention comprises: said expansion valve being a solenoid operated valve having a valve body with a flow passage therewithin for the flow of refrigerant therethrough, a valve seat constituting a portion of said flow passage, a valve member selectively movable between a closed position in which it is sealingly engageable with said valve seat so as to block the flow of refrigerant through said flow passage and an open position in which said valve member is clear of said valve seat permitting the flow of refrigerant through said flow passage, a solenoid actuator for effecting movement of said valve member between its closed and its open position upon energization and de-energization of said solenoid actuator, a spring for resiliently biasing said valve member towards its closed position, and control means for periodically energizing and de-energizing said solenoid actuator with the ratio of open time to the length of the period of said valve being responsive to one or more parameters of said refrigeration system thereby to regulate the flow of refrigerant through said expansion valve, said control means including means for sensing the superheat of the refrigerant discharged from said evaporator, means for generating a setpoint signal T2 representative of a desired operating condition of the refrigeration system, said control means further including means for generating an integrator count signal corresponding to a predetermined ratio of valve open time to the length of the period which is greater than zero, said integrator count signal generating means further having means for comparing said superheat to said set point signal and if the difference between said superheat and said set point is less than zero, an increment will be subtracted from said predetermined ratio of energization time to the length of said period, and if the difference between said superheat and said set point is greater than zero, an increment will be added to said predetermined ratio of energization time to the length of said period.