Patent ID: 6263684
Filing Date: 2001-07-24
Classification: F25B,G01F

Abstract:
A refrigerant flow meter comprising:a refrigerant flow meter housing having:an input fitting;an output fitting in connection with the input fitting through a refrigerant flow passageway;two concentrically aligned sensor windows in photo transferring connection with the refrigerant flow passageway;a visual fluid flow verification window in viewing connection with the refrigerant flow passageway; anda paddle wheel flow transducer assembly including a photomicrosensor assembly installed across the two concentrically aligned sensor windows such that a photo signal is transferred through the two concentrically aligned sensor windows and a paddle wheel rotatably installed within the refrigerant flow passageway between the two concentrically aligned sensor windows and having a number of equally spaced openings formed therethrough that sequentially pass between the two concentrically aligned sensor windows when the paddle wheel rotates to cause a pulsing volume signal output from the photomicrosensor assembly proportional to the volume of refrigerant flow through the refrigerant flow passageway; anda microprocessor circuit including:a microcontroller having a random access memory, a read only memory, and a refrigerant volume input in electrical connection with the volume output of the photomicrosensor assembly;a housing temperature sensor mechanically mounted to the refrigerant flow meter housing and having a housing temperature signal output in electrical connection with a housing temperature input of the microcontroller;an ambient temperature sensor mechanically mounted away from to the refrigerant flow meter housing and having an ambient temperature signal output in electrical connection with an ambient temperature input of the microcontroller;a material select switch in electrical connection with a material select input of the microcontroller;a material index switch in electrical connection with a material index input of the microcontroller;a reset switch in electrical connection with a reset input of the microcontroller; anda display assembly including a display driver in electrical connection between a display output of the microcontroller and a display input of a visual display device;the microcontroller having a look up table of information on a number of refrigerant materials programmed therein that is selected by a user using the material and select switches;the microcontroller being programmed to monitor the pulsing volume signal output from the photomicrosensor assembly; calculate a volume quantity based on an accumulated value of the pulsing volume signal and the temperature sensed by the housing and ambient temperature sensors; and display the volume quantity on the display assembly;the microcontroller resetting the accumulated value of the pulsing volume signal to zero when the reset switch is depressed.