Abstrict A light weight, refrigerant flow meter that calculates the quantity
of refrigerant that has flowed through the refrigerant flow meter
for a given period of time and provides a continuous visual display
output of the quantity of refrigerant transferred between a refrigerant
container and a system being charged with refrigerant.
Claims What is claimed is:
1. 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; and
a 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; and
a 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; and
a 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.
Description DESCRIPTION
1. Technical Field
The present invention relates to servicing equipment for refrigeration
systems and more particularly to a refrigerant flow meter that includes
a refrigerant flow meter housing and a microprocessor circuit; the
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; and a 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 there through
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;
the 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;
and a 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.
2. Background Art
When repairing an air conditioning unit that requires the repair
and resealing of the system, the refrigerant must be replaced within
the system prior to resealing the system. This is typically accomplished
by hooking a container of refrigerant to a fitting on the system
and then opening the container until a precise quantity of refrigerant
is transferred from the container to the system. Determining the
precise quantity of refrigerant transferred to the system can be
difficult and is typically accomplished using a scale to weigh the
container before and after the transfer has occurred. The scale
is large, bulky to carry and subject to variations that can cause
significant errors in the quantity of refrigerant transferred. In
addition, if the scale is dropped, it often has to be sent for recalibration
by a scale technician. It would be a benefit, therefore, to have
a small, light weight refrigerant flow meter that would calculate
the quantity of refrigerant that has flowed through the refrigerant
flow meter for a given period of time and provide a continuous visual
display output of the quantity of refrigerant transferred between
a refrigerant container and a system being charged with refrigerant.
GENERAL SUMMARY DISCUSSION OF INVENTION
It is thus an object of the invention to provide a refrigerant
flow meter that includes a refrigerant flow meter housing and a
microprocessor circuit; The 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; and
a 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; the 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; and a 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.
Accordingly, a refrigerant flow meter is provided. The refrigerant
flow meter includes a refrigerant flow meter housing and a microprocessor
circuit; the 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; and a 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;
the 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;
and a 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.
BRIEF DESCRIPTION OF DRAWINGS
For a further understanding of the nature and objects of the present
invention, reference should be made to the following detailed description,
taken in conjunction with the accompanying drawings, in which like
elements are given the same or analogous reference numbers and wherein:
FIG. 1 is a perspective view of an exemplary embodiment of the
refrigerant flow meter of the present invention.
FIG. 2 is a detail perspective view of an exemplary embodiment
of the refrigerant flow meter housing in isolation.
FIG. 3 is a schematic drawing of the microprocessor circuit.
FIG. 4 is a plan view of the top of the refrigerant flow meter
of FIG. 1.
EXEMPLARY MODE FOR CARRYING OUT THE INVENTION
FIGS. 1-4 show various aspects of an exemplary embodiment of the
refrigerant flow meter of the present invention, generally designated
10. Refrigerant flow meter 10 includes a refrigerant flow meter
housing, generally designated 12 and a microprocessor circuit,
generally designated 14.
Refrigerant flow meter housing 14 is constructed of machined brass
and includes an input fitting 16; an output fitting 18 in connection
with the input fitting through a refrigerant flow passageway 20
(shown in dashed lines); two concentrically aligned sensor windows
22 in photo transferring connection with the refrigerant flow passageway
20; a visual fluid flow verification window 24 in viewing connection
with the refrigerant flow passageway 20; and a paddle wheel flow
transducer assembly 28 (shown in dashed lines) including a photomicrosensor
assembly 30 installed across the two concentrically aligned sensor
windows 22 such that a photo signal is transferred through the two
concentrically aligned sensor windows 22 and a paddle wheel 32 is
rotatably installed within the refrigerant flow passageway 20 between
the two concentrically aligned sensor windows 22 that has a number
of equally spaced openings formed therethrough that sequentially
pass between the two concentrically aligned sensor windows 22 when
the paddle wheel 32 rotates to cause a pulsing volume signal output
from the photomicrosensor assembly 30 that is proportional to the
volume of refrigerant flow through the refrigerant flow passageway
20.
Microprocessor circuit 14 includes a microcontroller 40 having
a random access memory 42 a read only memory 44 and a refrigerant
volume input 46 in electrical connection with the volume output
48 of the photomicrosensor assembly 30. Microprocessor circuit 14
also includes a housing temperature sensor 50 that is mechanically
mounted to the refrigerant flow meter housing 12 and has a housing
temperature signal output 52 in electrical connection with a housing
temperature input 54 of microcontroller 40; an ambient temperature
sensor 56 mechanically mounted away from to the refrigerant flow
meter housing 12 and having an ambient temperature signal output
58 in electrical connection with an ambient temperature input 60
of the microcontroller 40; a material select switch 62 in electrical
connection with a material select input 64 of the microcontroller
40; a material index switch 66 in electrical connection with a material
index input 68 of the microcontroller 40; a reset switch 70 in electrical
connection with a reset input 72 of the microcontroller 40; and
a display assembly 76 including a display driver 78 in electrical
connection between a display output 80 of the microcontroller 40
and a display input 82 of a liquid crystal visual display device
84.
Microcontroller 40 has a look up table of information on a number
of refrigerant materials programmed therein including refrigerants
such as R-12 R-22 R-502 R-134A, R-402A, R-402B, R-404A, R-407C,
R-500 and H.sub.2 O. Prior to use, the user selects the correct
refrigerant from the list sequentially pressing the material index
switch 64 until the correct refrigerant type is displayed in LCD
display 84 and then depressing material select switch 62.
Microcontroller 40 is programmed to monitor the pulsing volume
signal output from the photomicrosensor assembly 30; 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 5056; and display the volume quantity on the display assembly
76. Microcontroller 40 resets the accumulated value of the pulsing
volume signal to zero when the reset switch 70 is depressed.
It can be seen from the preceding description that a refrigerant
flow meter has been provided.
It is noted that the embodiment of the refrigerant flow meter described
herein in detail for exemplary purposes is of course subject to
many different variations in structure, design, application and
methodology. Because many varying and different embodiments may
be made within the scope of the inventive concept(s) herein taught,
and because many modifications may be made in the embodiment herein
detailed in accordance with the descriptive requirements of the
law, it is to be understood that the details herein are to be interpreted
as illustrative and not in a limiting sense.
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