Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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REFRIGERATIONIHEAT PUMP MODULE
The present invention relates to a refrigeration/heat pump module
of the type comprising a compressor, evaporator and condenser all of which are
mounted in a housing for communicating heat through a recirculating
refrigerant
to a liquid to be heated and extracting heat by the same refrigerant to a
liquid to
be cooled.
The present module is particularly but not exclusively designed for
refrigeration for example for the cooling pipes of an ice rink, a cold room or
a
freezer with the extracted heat being available for use in heating other
areas.
However the module can be used for general cooling and can use a geo thermal
loop for disposing of the unwanted energy.
SUMMARY OF THE INVENTION
It is one object of the present invention to provide an improved
module of this type which has a significantly improved efficiency of
operation.
It is a second object of the present invention to provide a module of
this type which has an improved layout of the elements for compact
construction
and ease of operation.
According to one aspect of the invention there is provided a
refrigeration/heat pump module comprising:
a rectangular housing having a closed bottom, a closed top and
four generally upstanding walls including a front wall and a rear wall
defining a
closed interior, and including a front panel in the front wall which can be
removed
to provide access to the closed interior;
a first inlet and a first outlet for a liquid to be heated;
a second inlet and a second outlet for liquid to be cooled;
a compressor mounted in the closed interior for compressing and
pumping a refrigerant;
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a condenser having a plurality of parallel plates dividing the
condenser into two paths between the plates, the condenser having a third
inlet
for refrigerant vapor, a third outlet for refrigerant liquid, a fourth inlet
connected to
the first inlet for the liquid to be heated and a fourth outlet connected to
the first
outlet for the liquid to be heated, the condenser being mounted within the
closed
interior;
an evaporator having a plurality of parallel plates dividing the
evaporator into two paths between the plates, the evaporator having a fifth
inlet
for refrigerant liquid, a fifth outlet for refrigerant vapor, a sixth inlet
connected to
the second inlet for the liquid to be cooled, a sixth outlet connected to the
second
outlet for the liquid to be cooled, the evaporator being mounted within the
closed
interior;
an expansion valve for releasing pressure in the refrigerant, and
connecting piping connecting the fifth outlet of the evaporator to the input
of the
compressor, for connecting the outlet of the compressor to the third inlet of
the
condenser, for connecting the third outlet of the condenser to the expansion
valve and connecting the expansion valve to the fifth inlet of the evaporator;
a capacity of the evaporator and a capacity of the condenser and a
capacity of the expansion valve and a capacity of the piping begin selected
relative to a capacity of the compressor such that a compression ratio of the
compressor is maintained less than 4.5:1;
and a compartment for electrical components mounted immediately
rearwardly of the front wall adjacent one side wall, the compartment for
electric
components having a front door panel which can be opened along side said front
panel and separately of the front panel..
According to a second aspect of the invention there is provided a
refrigeration/heat pump module comprising:
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a rectangular housing having a closed bottom, a closed top and
four generally upstanding walls including a front wall and a rear wall
defining a
closed interior;
a first inlet and a first outlet for a liquid to be heated;
a second inlet and a second outlet for liquid to be cooled;
a compressor mounted in the closed interior for compressing and
pumping a refrigerant;
a condenser having a plurality of parallel plates dividing the
condenser into two paths between the plates, the condenser having a third
inlet
for refrigerant vapor, a third outlet for refrigerant liquid, a fourth inlet
connected to
the first inlet for the liquid to be heated and a fourth outlet connected to
the first
outlet for the liquid to be heated, the condenser being mounted within the
closed
interior;
an evaporator having a plurality of parallel plates dividing the
evaporator into two paths between the plates, the evaporator having a fifth
inlet
for refrigerant liquid, a fifth outlet for refrigerant vapor, a sixth inlet
connected to
the second inlet for the liquid to be cooled, a sixth outlet connected to the
second
outlet for the liquid to be cooled, the evaporator being mounted within the
closed
interior;
an expansion valve for releasing pressure in the refrigerant, and
connecting piping connecting the fifth outlet of the evaporator to the input
of the
compressor, for connecting the outlet of the compressor to the third inlet of
the
condenser, for connecting the third outlet of the condenser to the expansion
valve and connecting the expansion valve to the fifth inlet of the evaporator;
a capacity of the evaporator and a capacity of the condenser and a
capacity of the expansion valve and a capacity of the piping begin selected
relative to a capacity of the compressor such that a compression ratio of the
compressor is maintained less than 4.5:1;
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wherein the condenser is arranged adjacent to and parallel to one
side wall, wherein the evaporator is located adjacent to and parallel to an
opposed side wall;
wherein the compressor is located between the condenser and the
evaporator;
and wherein there is provided a filter for the refrigerant having a
cylindrical canister located in front of the compressor
According to a third aspect of the invention there is provided a
refrigeration/heat pump module comprising:
a rectangular housing having a closed bottom, a closed top and
four generally upstanding walls including a front wall and a rear wall
defining a
closed interior;
a first inlet and a first outlet for a liquid to be heated;
a second inlet and a second outlet for liquid to be cooled;
a compressor mounted in the closed interior for compressing and
pumping a refrigerant;
a condenser having a plurality of parallel plates dividing the
condenser into two paths between the plates, the condenser having a third
inlet
for refrigerant vapor, a third outlet for refrigerant liquid, a fourth inlet
connected to
the first inlet for the liquid to be heated and a fourth outlet connected to
the first
outlet for the liquid to be heated, the condenser being mounted within the
closed
interior;
an evaporator having a plurality of parallel plates dividing the
evaporator into two paths between the plates, the evaporator having a fifth
inlet
for refrigerant liquid, a fifth outlet for refrigerant vapor, a sixth inlet
connected to
the second inlet for the liquid to be cooled, a sixth outlet connected to the
second
outlet for the liquid to be cooled, the evaporator being mounted within the
closed
interior;
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an expansion valve for releasing pressure in the refrigerant, and
connecting piping connecting the fifth outlet of the evaporator to the input
of the
compressor, for connecting the outlet of the compressor to the third inlet of
the
condenser, for connecting the third outlet of the condenser to the expansion
valve and connecting the expansion valve to the fifth inlet ~f the evaporator;
a capacity of the evaporator and a capacity of the condenser and a
capacity of the expansion valve and a capacity of the piping begin selected
relative to a capacity of the compressor such that a compression ratio of the
compressor is maintained less than 4.5:1;
wherein the first inlet and first outlet and the second inlet and
second outlet are arranged at respective sides of the rear wall.
One embodiment of the invention will now be described in
conjunction with the accompanying drawings in which:
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a schematic illustration of a refrigeration/heat pump
system according to the present invention.
Figure 2 is an isometric view of the elements of Figure 1 mounted
in a housing.
Figure 3 is a horizontal cross sectional view through the apparatus
of Figure 2.
Figure 4 is a vertical cross sectional view through the apparatus of
Figure 2.
In the drawings like characters of reference indicate corresponding
parts in the different figures.
DETAILED DESCRIPTION
The refrigeration/heat pump system is shown in Figure 2 mounted
in the housing and the various elements are shown in layout form in Figure 1.
The apparatus comprises a compressor 10 of a conventional construction
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operable to compress vapor supplied at an inlet 11 and a discharge vapor at
higher pressure at an outlet 12. Manually operable control valves 13 and 14
are
provided at the inlet and outlet respectively for disconnecting the compressor
from the system and allowing the compressor to be readily removed and
replaced.
The apparatus further includes an evaporator and a condenser 16.
Further the apparatus comprises an expansion valve 17, a canister type filter
18,
a sight glass 19, a solenoid operated control valve 20 and a temperature
control
device 21.
The evaporator, compressor and condenser are arranged in
conventional manner such that compressed vapor at the outlet 12 is supplied to
an inlet 22 of the condenser and forms a condensate within the condenser
discharging from the condenser through an outlet 23. The condensate from the
condenser at the outlet 23 passes through a pipe 24 via the solenoid control
valve 20 and the sight glass 19 through the filter 18 to the expansion valve
17
where the compressed liquid is expanded through an orifice. The dimension of
the orifice or expansion valve is controlled by the temperature control device
21
which actuates a bellows type orifice control system 25 through a tube 26. The
pressure in the liquid is thus released through the expansion valve and the
liquid
at lower pressure is supplied to an inlet 27 of the evaporator. Within the
evaporator the liquid changes phased form a vapor so that the vapor discharges
from the evaporator at an outlet 28 connected to the inlet 11 of the
compressor
by a pipe 29.
As is well known the condenser releases heat as the vapor
changes phase to the liquid so that the condenser forms a heat exchanger with
a
liquid supplied at an inlet 30 which passes to an inlet 31 on the condenser so
that heated liquid emerges at an outlet 32 of the condenser for connection to
an
outlet coupling 33 of the system.
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Similarly the evaporator extracts heat from a liquid to be cooled
which is supplied at a system inlet 34 for connection to an inlet 35 at the
top of
the evaporator so that the cooled liquid emerges at the bottom of the
evaporator
through an outlet 36 for connection to a system outlet 37.
The evaporator 15 is of the type employing a plurality of parallel flat
plates 15A so that the materials passing through the evaporator are in
intimate
heat communication through the parallel plates. A suitable evaporator of the
type concerned is manufactured by Flat Plate Inc. of York Pennsylvania known
as the "CH Series" liquid chiller. An evaporator of this type generally
includes a
distributor 15B at the bottom of the evaporator so that the liquid at the
inlet 27 is
effectively and equally distributed through the channels between the plates
for
passage through the evaporator in the most efficient manner.
The condenser 16 similarly is of the type manufactured by Flat
Plate Inc. under the type "C Series" and includes a series of parallel plates
16A.
A suitable compressor is manufactured by Maneurop of
Lawrenceville GA under product reference number MTE160HW.
The electrical components of the system are controlled by an
electrical control system 38 which acts to control the motor of the compressor
and the solenoid valve 20 in dependence upon requirements.
The present inventor has found that a significant improvement in
efficiency of the system can be obtained as measured in tons of cooling per hp
where one ton is equal to 12000BTU at 45°F. Using the selection of
components
as set forth hereinafter, the efficiency of the system can be increased from
the
conventional value of 0.75 tons/hp up to 0.95 tons per hp and generally
greater
than 1.0 tons/hp at ice rink design temperatures.
The present inventor has identified that the selection of the above
types of components that is the plate type evaporator and condenser when
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utilizing components which are significantly oversized relative to
conventional
systems in comparison with the capacity of the compressor.
Thus in one example a compressor of the order of 13.5 tons
capacity is utilized in conjunction with a condenser having the capacity of 15
tons, an expansion valve having a capacity of 14 tons and an evaporator having
a capacity of 20 tons.
While these components are conventionally mismatched, the
present inventor has found that this selection of components provides a
significant advantage in terms of efficiency. Thus the following
characteristics of
the system are obtained by this selection.
1. The compression ratio of the compressor is significantly
reduced relative to conventional systems in that the compression ratio is
reduced
to a level less than 4.5:1 and preferably less than 3.4:1. Conventional
systems
run at a compression ratio of 7:1 to 10:1.
2. The temperature drop in the refrigerant across the
condenser is maintained so that the temperature of the refrigerant emerging
from
the outlet 23 is less than 80°F. This compares with a conventional
system
having a temperature of the order of 90 to 120°F.
3. The super heat (that is the net difference between the
temperature read out at the suction outlet of the evaporator and the pressure
at
the same point converted by the conventional calculations to temperature) of
the
refrigerant at the compressor is less than 8°F.
4. The temperature drop across the evaporator of the liquid to
be cooled is less than 7°F and preferably of the order of 6.6°F.
5. The temperature rise across the evaporator of the refrigerant
is less than 10°F and preferably of the order of 8°F.
6. The temperature rise across the condenser of the liquid to
be heated is less than 10°F and preferably of the order of
9.5°F.
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7. The temperature drop of the refrigerant across the
condenser is greater than 28°F and preferably of the order of
30°F.
8. The temperature of the refrigerant at the fifth outlet is less
than 80°F.
9. The pressure drop in the refrigerant across the evaporator is
less than 8.9 PSIG.
10. The pressure drop of the refrigerant across the condenser is
less than 11 PSIG.
Turning now to Figures 2, 3 and 4, the layout of the components of
Figure 1 in the housing is shown in more detail.
The housing comprises a rectangular body defined by a top wall
40, a front wall 41, side walls 42 and 43 and a rear wall 44 together with a
base
45. The structure is formed from metal sheet to define a rigid self supporting
transportable container which is stiffened by beams where necessary in
accordance with good engineering practice.
The front wall 41 is defined by a rectangular front removable panel
46 which can be removed to define a rectangular opening 47 as shown in Figure
2. Along one side of the panel 46 is defined a vertical strip 48. Along the
opposed side of the panel 46 is defined a front door 49 covering a rectangular
opening 50 defining a vertical housing for receiving the electrical components
38.
Thus the housing 50 is defined in the corner between the front wall 41 and the
side wall 42 and is enclosed by a side wall 51 parallel to the side wall 42
and a
rear wall 53 parallel to the front wall 41 and the front door 49. The front
door 49
is hinged at 54 so that it can be moved to an open position 49A allowing
access
to the electrical components.
The compressor 10 is mounted centrally of the base 45 on a
support tray 56. The tray 56 includes a horizontal support wall which is
supported by a pair of flanges 57 and 58 each along a respective side of the
wall
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56 and each horizontal adjacent the base 45. The flanges 57 and 58 are
attached to the base wall 45 by a vibration dampening rubber support 59.
The compressor 10 is mounted on four legs 60 each of which is
bolted to support wall 56 and is attached thereto by double rubber resilient
5 vibration dampening elements 61 arranged on top of and below the support
wall
56. In this way the legs are vibration dampened relative to the support wall
56
and the support wall is vibration damp and relative to the base 45 thus
isolating
any vibration from the compressor and reducing the noise level of the
components.
10 The evaporator 15 is mounted within an insulated container 62
carried on a support tray 63 similar to the support tray 56. However the
support
tray 63 is simply welded to the base 45. The evaporator 15 is mounted in fixed
position within the insulated interior of the container 62 and the ducts
communicant to and from the evaporator pass through a front face of the
housing 62.
Similarly the condenser 16 is mounted within an insulated housing
65 carried on a tray 66 welded to the base 45. Again the ducts pass through a
front face of the insulated housing 65 for communication with the condenser
16.
The housings 62 and 65 are thus arranged adjacent the side walls
43 and 42 respectively with the plates of the heat exchanger parallel to the
side
walls. The condenser is located centrally between the housings 62 and 65
allowing simple communication of the pipes from the compressor to the
evaporator and condenser. Thus the pipe 24 containing the dryer 18 and the
site
glass 19 passes from the valve 17 vertically downwardly and then horizontally
across the front of the housing in front of the compressor 10 and the tray 56.
The pipe 24 then extends horizontally rearwardly and then upwardly for
connection to the outlet 23 of the condenser. A pipe 12A from the outlet 12 of
the compressor extends horizontally across in front of the compressor and then
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vertically upwardly and rearwardly for connection to the inlet 22 of the
condenser.
The pipe 29 extends from the top of the evaporator horizontally across the top
of
the compressor.
The first inlet 30 and the first outlet 33 are both provided on the
rear wall 44 of the housing at vertically spaced positions on the side
adjacent the
condenser. Similarly the second inlet 34 and the second outlet 37 are located
on
the rear wall 44 at positions symmetrical with the first inlet and outlet and
adjacent the evaporator 15. Thus the system connections 30, 33 and 34, 37 are
conveniently located on the rear wall. The rear wall 44 includes a removable
panel 70 in between the first and second inlets and outlets on the rear wall.
Thus the servicing of the system can be effected readily by removing the front
and rear panels 46, 70.
Since various modifications can be made in my invention as herein
above described, and many apparently widely different embodiments of same
made within the spirit and scope of the claims without departing from such
spirit
and scope, it is intended that all matter contained in the accompanying
specification shall be interpreted as illustrative only and not in a limiting
sense.
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