Patent Application
20050092002
This invention relates generally to vapor compression systems, and more particularly, to expansion devices for vapor compression systems.
In a closed-loop vapor compression cycle, heat transfer fluid changes state from a vapor to a liquid in the condenser, giving off heat to ambient surroundings, and changes state from a liquid to a vapor in the evaporator, absorbing heat from the ambient surroundings during vaporization. A typical vapor compression system includes a compressor for pumping heat transfer fluid, such as a Freon, to a condenser, where heat is given off as the heat transfer fluid condenses into a liquid. The heat transfer fluid then flows through a liquid line to an expansion device, where the heat transfer fluid undergoes a volumetric expansion. The heat transfer fluid exiting the expansion device is usually a low quality liquid vapor mixture. As used herein, the term “low quality liquid vapor mixture” refers to a low pressure heat transfer fluid in a liquid state with a small presence of flash gas that cools off the remaining heat transfer fluid as the heat transfer fluid continues on in a sub-cooled state. The expanded heat transfer fluid then flows into an evaporator. The evaporator includes a coil having an inlet and an outlet, wherein the heat transfer fluid is vaporized at a low pressure absorbing heat while it undergoes a change of state from a liquid to a vapor. The heat transfer fluid, now in the vapor state, flows through the coil outlet and exits the evaporator. The heat transfer fluid then flows through a suction line and back to the compressor. A typical vapor compression system may include more than one expansion device. Moreover, the expansion device may be placed in various locations within a vapor compression system. For example, as the heat transfer fluid flows into an evaporator it may flow through a second expansion device, where the heat transfer fluid undergoes a second volumetric expansion. Additionally, a typical vapor compression system may include a nozzle or fixed orifice.
In one aspect, the efficiency of the vapor compression cycle depends upon the precise control of the volumetric expansion of a heat transfer fluid in various locations within a vapor compression system. Heat transfer fluid is volumetrically expanded when the heat transfer fluid flows through an expansion device, such as a thermostatic expansion valve, a capillary tube, and a pressure control, or when the heat transfer fluid flows through a nozzle or fixed orifice. Often times, the rate at which a heat transfer fluid is volumetrically expanded needs to be varied depending on the conditions within the vapor compression system. Devices such as capillary tubes, pressure controls, nozzles, or fixed orifices are fixed in size and cannot vary the rate at which a heat transfer fluid is volumetrically expanded. While many thermostatic expansion valves can vary the rate at which a heat transfer fluid is volumetrically expanded, they are complex and rather costly to manufacture. Moreover, thermostatic expansion valves are not as precise as capillary tubes, pressure controls, nozzles, or fixed orifices, when it comes to controlling the rate at which heat transfer fluid is volumetrically expanded.
One of the major drawbacks with conventional designs of expansion valves is that each type of refrigerant used in a vapor compression system typically requires its own dedicated expansion valve and/or power head, each of which is appropriately sized to accommodate the properties (e.g., tonnages) of the specific refrigerant to be used. As a result, it has heretofore been necessary to purchase and maintain a large series of expansion valves and power heads, which is both costly and inconvenient. Moreover, when switching from one refrigerant to another, an operator has heretofore been forced to open the closed loop system in order to replace the expansion device and/or power head This task is oftentimes difficult to perform in the field and, moreover, is time-, cost-, and labor-intensive. Thus, it would be highly advantageous if a single expansion valve configured for use with multiple refrigerants were available.
The scope of the present invention is defined solely by the appended claims, and is not affected to any degree by the statements within this summary.
A first expansion valve embodying features of the present invention includes a housing containing an inlet and an outlet, one or both of which is configured for coupling to an expansion device; a valve orifice provided between the inlet and the outlet; a valve member configured for engagement with the valve orifice; and an expandable member coupled to the valve member by a transmitting element and configured for moving the valve member into and out of engagement with the valve orifice. The expansion device includes a flow-regulating member that contains at least a first and a second channel forming at least first and second channel orifices, respectively, such that a cross-sectional area of the first channel orifice is larger than a cross-sectional area of the second channel orifice. The flow of a heat transfer fluid between the inlet and the outlet is substantially prevented when the valve member fully engages the valve orifice, and the flow of the heat transfer fluid is permitted when the valve member is at least partially disengaged from the valve orifice. A cross-sectional area of the valve orifice is at least as large as the cross-sectional area of the first orifice. In some embodiments, the expansion valve further includes an adjustable cam element coupled to each of the expandable member and the transmitting element, such that movement of the valve member in relation to the valve orifice is facilitated or impeded based on orientation of the cam element.
A second expansion valve embodying features of the present invention includes a housing containing an inlet and an outlet, one or both of which is configured for coupling to an expansion device; a valve orifice provided between the inlet and the outlet; a valve member configured for engagement with the valve orifice; and an expandable member coupled to the valve member by a transmitting element and configured for moving the valve member into and out of engagement with the valve orifice. The expansion device includes a flow-regulating member that contains a primary channel and a plurality of secondary channels. The primary channel defines a primary channel orifice in the flow-regulating member and the plurality of secondary channels defines a plurality of secondary channel orifices in the flow-regulating member. The plurality of secondary channel orifices is located along a common periphery of the flow-regulating member, such that an axis passing through the primary channel orifice intersects a plane containing the common periphery at a unique point. At least one of the plurality of secondary channel orifices has a cross-sectional area larger than that of the others, and at least one of the plurality of secondary channels intersects the primary channel. A cross-sectional area of the valve orifice is at least as large as the largest cross-sectional area of the plurality of secondary channel orifices.
A third expansion valve embodying features of the present invention includes a housing containing an inlet and an outlet, one or both of which is configured for coupling to an expansion device; a valve orifice provided between the inlet and the outlet; a valve member configured for engagement with the valve orifice; an expandable member coupled to the valve member by a transmitting element and configured for moving the valve member into and out of engagement with the valve orifice; and an adjustable cam element coupled to each of the expandable member and the transmitting element. Movement of the valve member in relation to the valve orifice is modulated based on orientation of the cam element.
An expansion device assembly embodying features of the present invention includes: a first housing containing an inlet and an outlet; a valve orifice provided between the inlet and the outlet; a valve member configured for engagement with the valve orifice; an expandable member coupled to the valve member by a transmitting element and configured for moving the valve member into and out of engagement with the valve orifice; and an expansion device coupled to the inlet or the outlet. The expansion device includes: a second housing containing a first housing orifice; and at least one flow-regulating member within the housing. The flow-regulating member includes at least two secondary channels forming at least first and second secondary channel orifices, respectively, wherein a cross-sectional area of the first secondary channel orifice is larger than a cross-sectional area of the second secondary channel orifice, and wherein a cross-sectional area of the valve orifice is at least as large as the cross-sectional area of the first secondary channel orifice. Flow of a heat transfer fluid between the inlet and the outlet is substantially prevented when the valve member fully engages the valve orifice, and flow of the heat transfer fluid is permitted when the valve member is at least partially disengaged from the valve orifice.
A vapor compression system embodying features of the present invention includes: a line for flowing a heat transfer fluid; a compressor connected with the line for increasing at least one of a pressure and a temperature of the heat transfer fluid; a condenser connected with the line for at least partially liquefying the heat transfer fluid; an evaporator connected with the line for transferring heat from an ambient surrounding to the heat transfer fluid; and an expansion device assembly of a type described above.
A vehicle embodying features of the present invention includes an expansion device assembly of a type described above.
A method for operating a vapor compression system embodying features of the present invention includes flowing a heat transfer fluid through a line connected with each of a compressor for increasing at least one of a pressure and a temperature of the heat transfer fluid, a condenser for at least partially liquefying the heat transfer fluid, an evaporator for transferring heat from an ambient surrounding to the heat transfer fluid, and an expansion device assembly of a type described above.
For simplicity and clarity of illustration, elements shown in the Figures have not necessarily been drawn to scale. For example, dimensions of some elements are exaggerated relative to each other. Further, when considered appropriate, reference numerals have been repeated among the Figures to indicate corresponding elements.
Representative embodiments in accordance with the present invention are described below in reference to the appended drawings. It is to be understood that elements and features of the various representative embodiments described herein may be combined in different ways to produce new embodiments that likewise fall within the scope of the present invention. Accordingly, the description provided below, when provided in reference to one or more specific figures, is to be understood as being likewise applicable to other embodiments, including but not limited to those that are shown in other drawing figures that may or may not have been specifically referenced.
One embodiment of a vapor compression system 10 is illustrated in
In one embodiment, vapor compression system 10 includes a sensor 32 operably connected to expansion device 18. Sensor 32 can be used to vary the rate at which a heat transfer fluid is volumetrically expanded through expansion device 18. Preferably, sensor 32 is mounted to a portion of line 19, such as suction line 30, and is operably connected to expansion device 18. Sensor 32 can be any type of sensor known by those skilled in the art designed to detect conditions in and around vapor compression system 10, such as the temperature, pressure, enthalpy, and moisture of heat transfer fluid or any other type of conditions that may be monitored in and around vapor compression system 10. For example, sensor 32 may be a pressure sensor that detects the pressure of heat transfer fluid at a certain point within vapor compression system 10, or sensor 32 may be a temperature sensor which detects the temperature of ambient surroundings 11 around vapor compression system 10. Preferably, sensor 32 is operably connected to expansion device 18 through control line 33.
Vapor compression system 10 can utilize any commercially available heat transfer fluid such as refrigerants, including but not limited to chlorofluorocarbons such as R-12 which is a dichlorodifluoromethane, R-22 which is a monochlorodifluoromethane, R-500 which is an azeotropic refrigerant containing R-12 and R-152a, R-503 which is an azeotropic refrigerant containing R-23 and R-13, and R-502 which is an azeotropic refrigerant containing R-22 and R-115. Vapor compression system 10 can also utilize heat transfer fluids including but not limited to refrigerants R-13, R-113, 141b, 123a, 123, R-114, and R-11. Additionally, vapor compression system 10 can utilize heat transfer fluids including but not limited to hydrochlorofluorocarbons such as 141b, 123a, 123, and 124; hydrofluorocarbons such as R-134a, 134, 152, 143a, 125, 32, 23; azeotropic HFCs such as AZ-20 and AZ-50 (commonly known as R-507); non-halogenated refrigerants such as R-717 (commonly known as ammonia); and blended refrigerants such as MP-39, HP-80, FC-14, and HP-62 (commonly known as R-404a). Accordingly, it should be appreciated that the particular heat transfer fluid or combination of heat transfer fluids utilized in the present invention is not deemed to be critical to the operation of the present invention since this invention is expected to operate with a greater system efficiency with virtually all heat transfer fluids than is achievable by any previously known vapor compression system utilizing the same heat transfer fluid.
In one embodiment, compressor 12 compresses heat transfer fluid, to a relatively high pressure and temperature. The temperature and pressure to which heat transfer fluid is compressed by compressor 12 will depend upon the particular size of vapor compression system 10 and the cooling load requirements of vapor compression system 10. Compressor 12 then pumps heat transfer fluid into discharge line 20 and into condenser 14. In condenser 14, a medium such as air, water, or a secondary refrigerant is blown past coils within condenser 14 causing the pressurized heat transfer fluid to change to a liquid state. The temperature of the heat transfer fluid drops as the latent heat within the heat transfer fluid is expelled during the condensation process. Condenser 14 discharges the liquefied heat transfer fluid to liquid line 22.
As shown in
While in the above embodiment expansion device 18 is connected with saturated vapor line 28 and liquid line 22, expansion device 18 may be connected with any component within vapor compression system 10, and expansion device 18 may be located at any point within vapor compression system 10. Preferably, expansion device 18 is located at a point within vapor compression system 10 in which it is desired to volumetrically expand heat transfer fluid, such as between condenser 14 and evaporator 16. More preferably, expansion device 18 is located at a point within vapor compression system 10 in which it is desired to vary the rate at which a heat transfer fluid is volumetrically expanded, such as between condenser 14 and evaporator 16, as illustrated in
Shown in
Blade 48 is movable between a first position, as illustrated in
In one embodiment, expansion device 18 includes a first blade 50 and a second blade 52, as illustrated in
In one embodiment, expansion device 18 includes a single blade 48, wherein single blade 48 defines a second orifice 46, as illustrated in
In one embodiment expansion device 18 includes a series of blades 48, wherein the series of blades 48 define a second orifice 46, as illustrated in
In one embodiment, sensor 32 controls the movement of at least one blade 48 between a first position and a second position. Preferably, sensor 32 is connected with a moving device (not shown), such as an electric motor or an electromagnet, wherein the moving device can be used to automatically move blade 48 from a first position to a second position upon receiving a signal from sensor 32.
In one embodiment, expansion device 18 includes a first sheet 60 defining a first orifice 62, and a second sheet 64 overlapping the first sheet 60, as illustrated in
Preferably, heat transfer fluid is used to lubricate either blades 48 or first and second sheets 60, 64, so that blades 48 and/or first and second sheets 60, 64 may move more freely about.
In one embodiment, second sheet 64 defines multiple orifices 66 and first sheet 60 defines a single orifice 62, wherein the size and shape of orifice 62 allows orifice 62 to overlap multiple orifices 66, as illustrated in
Another embodiment of expansion device 18 is shown in
Ball 84 sits within bore 72 of housing 80 and is sandwiched between two seats 86 that are sized to be sealingly received in the bore 72 of the housing 80. While in this embodiment ball 84 is in the shape of a sphere, ball 84 can have other shapes, such as other three-dimensional curvilinear shapes and other regular and irregular geometric structures. Representative alternative shapes include but are not limited to hemispheres, spherical cones, ellipsoids, oblate spheroids, prolate spheroids, catenoids, cylinders, truncated cylinders, cones, truncated cones, parallelograms, pyramids, and the like.
Ball 84 forms a notch 126 that receives an adjustment stem 88 through a second bore 130 of housing 80. A stem washer 90 surrounds the base of adjustment stem 88. The adjustment stem 88 receives a packing 98, a packing follower 100, a packing spring 102, a spring cap 104, and a thrust bearing 106 which overlie the washer 90 and are generally located within the bore 130. A base 96 holds the adjustment stem 88 within bore 130. A tip 89 of adjustment stem 88 pokes through an opening in the base 96. A handle 112 forms an opening 116 that is fitted over the tip 89. A handle set screw 114 secures the handle 112 to adjustment stem 88. As the handle 112 rotates in a rotational direction R, adjustment stem 88 and the ball 84 also rotate in a direction R, as illustrated in
As handle 112 rotates, ball 84 is movable between a first position and a second position. Ball 84 forms at least two channels 118 which each form a channel orifice 76, as shown, for example, in
While a channel, such as first channel 120, may define a number of orifices along the developed length of that channel, as defined herein, the channel orifice 76 is the orifice defined by a channel that has the smallest cross-sectional area from any other orifice defined by that channel. For example, as illustrated in
The heat transfer fluid flows in a direction F through line 19 and into the expansion device 78 through the housing orifice 74 having a diameter D, as illustrated in
As defined herein, an orifice, such as orifice 74, is made larger when the cross-sectional area of the orifice is effectively increased and an orifice is made smaller when the cross-sectional area of the orifice is effectively decreased. By moving the ball 84 from a first position to a second position, the cross-sectional area of housing orifice 74 can be effectively increased or decreased; thus, the rate of volumetric expansion within a heat transfer fluid which flows through the housing orifice 74 and through expansion device 78 can be precisely controlled and varied.
The ball 84 can be either manually moved from a first position to a second position or automatically moved, by means of a motor or other means, from a first position to a second position. In one embodiment, sensor 32 controls the movement of ball 84 between a first position and a second position. Preferably, sensor 32 is connected with a moving device (not shown), such as an electric motor or an electromagnet, wherein the moving device can be used to automatically move ball 84 from a first position to a second position upon receiving a signal from sensor 32.
In one embodiment, the ball 84 forms a first channel 120 having an orifice 76 with an effective cross-sectional area C, a second channel 122 having an orifice 76 with an effective cross-sectional area B, and a third channel 124 having an orifice 76 with an effective cross-sectional area A, wherein the effective cross-sectional area A is not equal to effective cross-sectional areas C or B, and the effective cross-sectional area C is not equal to the effective cross-sectional area B, as illustrated in
In one embodiment, the first channel 120 and the second channel 122 form an intersection 132, wherein the path of the first channel 120 crosses the path of the second channel 122, as illustrated in
In one embodiment, the first channel 120 and the second channel 122 are positioned near one another so that the heat transfer fluid may flow through either the first channel 120, the second channel 122, or through both the first and the second channel 120, 122, depending on the position of ball 84, as illustrated in
Another embodiment of expansion device 18 is shown in
Preferably, housing 138 includes a rigid, steel material; however housing 138 can be manufactured from any rigid material known by those skilled in the art, such as ceramics, carbon fiber, any metal or metallic alloy, any plastic, or any other rigid material. Housing 138 is preferably constructed as a two-piece structure analogous to the two-piece structure shown in
Flow-regulating member 140 sits within first bore 142 of housing 138 and is sandwiched between a washer 152 and a seat 154 that are sized to be sealingly received in the first bore 142 of the housing 138. As shown in
Flow-regulating member 140 has a notch 156 that receives an adjustment stem 158 through a top bore 160 of housing 138. A packing ring 162 surrounds the base of adjustment stem 158. The adjustment stem 158 receives a stem seal 164, a stem packing ring 166, a stem locking nut 168, and a stem cap 170. The stem cap 170 is threaded on an interior surface 172 and connects with a complementary threaded portion 174 of top bore 160. As shown in
Stem cap 170 comprises an out-of-round portion 176. As shown in
The flow-regulating member 140, shown in
The plurality of secondary channel orifices 184 are located along a common periphery 186 of the flow-regulating member 140, such that an axis A3 passing through the primary channel orifice 182 intersects a plane P1 containing the common periphery 186 at a unique point P. In presently preferred configurations, wherein the flow-regulating member 140 is spherical, the secondary channel orifices 184 are located along the equatorial periphery of the sphere and the primary channel orifice 182 is located at a pole of the sphere, such that the axis A3 passing through the primary channel orifice 182 is substantially perpendicular to axes A4 passing through each of the plurality of secondary channel orifices 184.
In presently preferred configurations, the secondary channel orifices 184 have different cross-sectional areas, and the secondary channels 180 intersect the primary channel 178, as shown in
As adjustment stem 158 rotates, flow-regulating member 140 is movable between a first position and a second position, such that at least one of the primary channel orifice 182 and the plurality of secondary channel orifices 184 is configured for being substantially aligned with one or the other of the first housing orifice 144 and the second housing orifice 146. As depicted in
The heat transfer fluid flows in a direction F through line 136 and into the expansion device 134 through the first housing orifice 144 as illustrated in
In presently preferred configurations, the secondary channel orifices 184 are spaced apart at regular intervals along the common periphery 186, as best shown by
As shown in
As defined herein, an orifice, such as first housing orifice 144, is made larger when the cross-sectional area of the orifice is effectively increased and an orifice is made smaller when the cross-sectional area of the orifice is effectively decreased. By moving the flow-regulating member 140 from a first position to a second position, the cross-sectional area of first housing orifice 144 can be effectively increased or decreased; thus the rate of volumetric expansion within a heat transfer fluid which flows through the first housing orifice 144 and through expansion device 134 can be precisely controlled and varied.
The flow-regulating member 140 can be either manually moved from a first position to a second position or automatically moved, by means of a motor or other means, from a first position to a second position. In one embodiment, sensor 32 controls the movement of flow-regulating member 140 between a first position and a second position. Preferably, sensor 32 is connected with a moving device (not shown), such as an electric motor or an electromagnet, wherein the moving device can be used to automatically move flow-regulating member 140 from a first position to a second position upon receiving a signal from sensor 32.
Expansion device 18 may be combined with a traditional expansion device, wherein the traditional expansion device volumetrically expands heat transfer fluid at a fixed rate. By combining expansion device 18 with a traditional expansion device, heat transfer fluid can be volumetrically expanded at a varied rate, and thus simulate the effect of a thermostatic expansion valve at a reduced cost.
Expansion devices embodying features of the present invention may be advantageously configured for use with expansion valves of the type containing a variably sized orifice provided by the combination of a valve seat and a valve member, wherein the valve member is configured for full, partial or non engagement with the valve seat, thereby controlling the size of the valve seat orifice. Expansion valve 42 shown in
By employing one of the adjustable expansion devices described herein, the costly and inconvenient requirement of purchasing entire sets of variably sized power heads and/or expansion valves, and the necessity of changing one or both of these parts each time a different refrigerant is to be employed may be significantly reduced or avoided altogether.
Thus, if expansion valve 194 is connected to expansion device 134 of
As shown in
In the representative configuration shown in
It is to be understood that the simplified depiction of expansion valve 194 shown in
It is further to be understood that the term “coupled,” as used herein, is intended broadly to encompass both direct and indirect coupling. Thus, first and second parts are said to be coupled together when they are directly connected and/or functionally engaged (e.g. by direct contact), as well as when the first part is functionally engaged with an intermediate part which is functionally engaged either directly or via one or more additional intermediate parts with the second part. Also, two elements are said to be coupled when they are functionally engaged (directly or indirectly) at some times and not functionally engaged at other times.
By providing a valve orifice 202 that is larger in cross-section than conventional valve seats, a single expansion valve 194 may be used to accommodate the throughput of a great many refrigerants when used in combination with one of the adjustable expansion devices described herein. By way of example, expansion device 78 shown in
In expansion device assemblies in which expansion valve 194 is coupled, for example, to expansion device 78 of
In some embodiments, as shown in
As shown in the simplified depiction of
In alternative embodiments, cam element 214 may be provided by a removable cam member, such as a removable cam disc or a removable cam wafer, which are introduced into expansion valve 194 by removing power head 210 and inserting the removable cam member in position to contact and/or be coupled—directly or indirectly—to transmitting element 208 and expandable member 206. The size and/or geometric configuration of the removable cam member, as well as the deformability of the material from which the removable cam member is manufactured, may each affect the level of pressure being applied to expandable member 206 and/or transmitting element 208, thereby modulating the freedom of movement available to valve member 204 in relation to valve orifice 202. All manner of regular and irregular geometric shapes are contemplated for use in accordance with the above-described removable cam members, including but not limited to discs or wafers (e.g., having cross-sections that are circular, elliptical, square, rectangular, triangular, spherical triangular, or the like), hemispheres, spherical cones, ellipsoids, oblate spheroids, prolate spheroids, catenoids, spherical lunes, spherical wedges, cylinders, truncated cylinders, ungula of cylinders, quoits, toroids, zones of spheres, parallelepipeds, cubes, tetrahedrons, bispheonids, parallelograms, pyramids, and the like. The removable cam element may optionally be attached to one or more interior portions of expansion valve 194, including but not limited to expandable member 206 and/or head portion 220 of transmitting element 208.
The above-described embodiments shown in
In practice, it may be preferable to provide a small series of expansion valves embodying features of the present invention, each member of which is configured for accommodating a range of refrigerant tonnages, rather than providing only one expansion valve designed to accommodate a full gamut of tonnages. Notwithstanding, this represents a considerable advantage over conventional designs in which a particular tonnage is accommodated by a dedicated expansion valve. By way of illustration, a first expansion valve embodying features of the present invention may accommodate a first range of tonnages (e.g., ½, ¾, 1, 1{fraction (1/2)}, 2, 2{fraction (1/2)}), a second expansion valve embodying features of the present invention may accommodate a second range of tonnages (e.g., 5-11), and a third expansion valve embodying features of the present invention may accommodate a third range of tonnages (e.g., 16-30). In this illustrative example, three expansion devices in accordance with the present invention may be used to replace a much larger number of conventional expansion valves, thereby dramatically reducing costs and field installation labor. It is to be understood, of course, that the tonnages and ranges indicated above are purely illustrative and are not to be construed as limiting or necessary for the practice of the present invention.
Those skilled in the art will appreciate that numerous modifications can be made to enable vapor compression system 10 to address a variety of applications. For example, vapor compression system 10 operating in a retail food outlet may include a number of evaporators 16 that can be serviced by a common compressor 12. Also, in applications requiring refrigeration operations with high thermal loads, multiple compressors 12 can be used to increase the cooling capacity of the vapor compression system 10.
Those skilled in the art will recognize that vapor compression system 10 can be implemented in a variety of configurations. For example, the compressor 12, condenser 14, expansion device 18, and the evaporator 16 can all be housed in a single housing and placed in a walk-in cooler. In this application, the condenser 14 protrudes through the wall of the walk-in cooler and ambient air outside the cooler is used to condense the heat transfer fluid. In another application, vapor compression system 10 can be configured for air-conditioning a home or business. In yet another application, vapor compression system 10 can be used to chill water. In this application, the evaporator 16 is immersed in water to be chilled. Alternatively, water can be pumped through tubes that are meshed with the evaporator coil 44. In a further application, vapor compression system 10 can be cascaded together with another system for achieving extremely low refrigeration temperatures. For example, two vapor compression systems using different heat transfer fluids can be coupled together such that the evaporator of a first system provides a low temperature ambient. A condenser of the second system is placed in the low temperature ambient and is used to condense the heat transfer fluid in the second system.
As known by one of ordinary skill in the art, every element of vapor compression system 10 described above, such as evaporator 16, liquid line 22, and suction line 30, can be scaled and sized to meet a variety of load requirements. In addition, the refrigerant charge of the heat transfer fluid in vapor compression system 10 may be equal to or greater than the refrigerant charge of a conventional system.
Furthermore, it is to be understood that considerable variation can be made in the parts of vapor compression systems, expansion devices, and flow-regulating members embodying features of the present invention, and in the quantity, connectivity, and placement of such parts. For example, the placement and quantity of compressors and/or condensers and/or evaporators and/or expansion devices can vary from one vapor compression system to another. Similarly, the inclusion and placement of sensors in such vapor compression systems are variables. These and related variations are well known to those of ordinary skill in the art, and fall within the scope of the appended claims and their equivalents.
Thus, it is apparent that there has been provided, in accordance with the invention, a vapor compression system that fully provides the advantages set forth above. Although the invention has been described and illustrated with reference to specific illustrative embodiments thereof, it is not intended that the invention be limited to those illustrative embodiments. Those skilled in the art will recognize that variations and modifications can be made without departing from the spirit of the invention. For example, non-halogenated refrigerants can be used, such as ammonia, and the like can also be used. It is therefore intended to include within the invention all such variations and modifications that fall within the scope of the appended claims and equivalents thereof.
This application is a continuation-in-part of application Ser. No. 10/327,707, filed Dec. 20, 2002, which is a continuation-in-part of application Ser. No. 09/809,798, filed Mar. 16, 2001, which is a continuation-in-part of application Ser. No. 09/661,477, filed Sep. 14, 2000, now U.S. Pat. No. 6,401,470. The entire contents of all of the above-identified documents are incorporated herein by reference, except that in the event of any inconsistent disclosure or definition from the present application, the disclosure or definition herein shall be deemed to prevail.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 10327707 | Dec 2002 | US |
| Child | 10948106 | Sep 2004 | US |
| Parent | 09809798 | Mar 2001 | US |
| Child | 10327707 | Dec 2002 | US |
| Parent | 09661477 | Sep 2000 | US |
| Child | 09809798 | Mar 2001 | US |
