Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
85 words
Apparatus for controlling operation of an expansion valve and compressor in a heat transfer system, comprising: means for determining high side pressure of working fluid in the system; means for determining the working fluid state after the working fluid has passed through the evaporator; and control means for controlling operation of the expansion valve as a function of the detected working fluid state based on a state set point, said control means adjusting said state set point based on the working fluid high side pressure.
Claim 2
Dependent Claim
85 words
Apparatus for controlling operation of an expansion valve and compressor in a heat transfer system, comprising: means for determining high side pressure of working fluid in the system; means for determining the working fluid state after the working fluid has passed through the evaporator; and control means for controlling operation of the expansion valve as a function of the detected working fluid state based on a state set point, said control means adjusting said state set point based on the working fluid high side pressure.
Claim 3
Dependent Claim
24 words
The apparatus of claim 1 wherein said working fluid state corresponds to quality of the working fluid on the outlet side of the evaporator.
Claim 4
Dependent Claim
24 words
The apparatus of claim 1 wherein said working fluid state corresponds to superheat of the working fluid on the outlet side of the evaporator,
Claim 5
Dependent Claim
35 words
The apparatus of claim 1 wherein said means for determining the working fluid state comprises a resistance temperature sensor, said control means being operable to determine thermal conductance between the sensor and the working fluid.
Claim 6
Dependent Claim
25 words
The apparatus of claim 4 wherein said control means calculates said thermal conductance based on power dissipated by the sensor during a self-heated time period.
Claim 7
Dependent Claim
55 words
The apparatus of claim 1 wherein said control means raises a working fluid quality set point in response to an increase in high side pressure above a first value, said increased quality set point producing a reduction in demand for mass flow through the valve to reduce high side pressure without turning the compressor off.
Claim 8
Dependent Claim
26 words
The apparatus of claim 6 wherein said first value corresponds to a high side pressure higher than the pressure at which a condenser fan is activated.
Claim 9
Independent Claim
78 words
A method for controlling operation of a compressor and expansion valve in a heat transfer system including the steps of detecting high side pressure of the working fluid; detecting a state of the working fluid between the evaporator outlet and the compressor inlet; controlling operation of the expansion valve as a function of the detected working fluid state based on a state set point; and adjusting the state set point as a function of the high side pressure.
Claim 10
Independent Claim
78 words
A method for controlling operation of a compressor and expansion valve in a heat transfer system including the steps of detecting high side pressure of the working fluid; detecting a state of the working fluid between the evaporator outlet and the compressor inlet; controlling operation of the expansion valve as a function of the detected working fluid state based on a state set point; and adjusting the state set point as a function of the high side pressure.