Pressure accumulators for HVAC&R systems

Abstract

The heating, ventilation, air conditioning, and / or refrigeration (HVAC&R) system (10) includes a compressor (32) having a bearing (150). The HVAC&R system (10) also includes a lubricant circuit (202) configured to direct a flow of fluid to the bearing (150). Additionally, the HVAC&R system (10) includes a pressure accumulator (208) upstream of the bearing (150) and fluidly coupled to the lubricant circuit (202). The pressure accumulator (208) is configured to receive and contain a portion of the fluid from the lubricant circuit (202).

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 529,974, entitled "PRESSURE ACCUMULATOR FOR HVAC&R SYSTEM," filed July 31, 2023, and U.S. Provisional Patent Application No. 63 / 443,921, entitled "BEARING SYSTEM FOR HVAC&R SYSTEM," filed February 7, 2023, each of which is incorporated herein by reference in its entirety for all purposes. [Background technology]

[0002] This section is intended to introduce the reader to various aspects of the art that may be related to various aspects of the present disclosure, as described below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.

[0003] Chiller systems, or vapor compression systems, utilize a working fluid (e.g., refrigerant, etc.) that changes phase between vapor, liquid, and mixtures thereof in response to exposure to different temperatures and pressures within the chiller system's components. The chiller system may place the working fluid in a heat exchange relationship with a conditioned fluid (e.g., water) and deliver the conditioned fluid to conditioned equipment and / or a conditioned environment served by the chiller system. In such applications, the conditioned fluid may be routed through downstream equipment, such as an air handler, to condition other fluids, such as building air. The chiller system may include a compressor configured to pressurize the working fluid and circulate it through the chiller system's working fluid circuit. In some applications, the compressor's shaft may be rotatably driven by a motor to drive rotation of the compressor's impeller, which pressurizes the working fluid. Traditionally, compressors include bearings configured to facilitate shaft rotation. Unfortunately, existing bearings utilized with compressors can be complex and expensive and / or contribute to inefficiencies in the operation of the chiller system. Summary of the Invention

[0004] A summary of certain embodiments disclosed herein is set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of these particular embodiments, and that these aspects are not intended to limit the scope of the disclosure. Indeed, the disclosure may encompass a variety of aspects that may not be set forth below.

[0005] In one embodiment, a heating, ventilation, air conditioning, and / or refrigeration (HVAC&R) system includes a compressor having a bearing. The HVAC&R system also includes a lubricant circuit configured to direct a flow of fluid to the bearing. Additionally, the HVAC&R system includes a pressure accumulator upstream of the bearing and fluid-coupled to the lubricant circuit. The pressure accumulator is configured to receive and contain a portion of fluid from the lubricant circuit.

[0006] In another embodiment, a heating, ventilation, air conditioning, and / or refrigeration (HVAC&R) system includes a compressor having a bearing. The HVAC&R system also includes a conduit configured to direct a pressurized flow of fluid to the bearing. Additionally, the HVAC&R system includes a pressure accumulator fluidly coupled to the conduit. The pressure accumulator is configured to apply a force to the fluid in the conduit based on a change in pressure of the fluid in the conduit.

[0007] In another embodiment, a heating, ventilation, air conditioning, and / or refrigeration (HVAC&R) system includes a compressor configured to pressurize a working fluid and circulate the working fluid through a working fluid circuit of the HVAC&R system. The compressor includes a bearing. The HVAC&R system includes a lubricant circuit extending from the working fluid circuit to the bearing. Additionally, the HVAC&R system includes a pump disposed along the working fluid circuit and configured to direct a portion of the working fluid to the bearing. Further, the HVAC&R system includes a pressure accumulator fluidly coupled to the lubricant circuit. The pressure accumulator is configured to store a predetermined volume of pressurized working fluid.

[0008] The various aspects of the present disclosure may be better understood by reading the following detailed description and by reviewing the drawings, in which: [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view of an embodiment of a building that may utilize a heating, ventilation, air conditioning, and / or refrigeration (HVAC&R) system in a commercial environment, according to an aspect of the present disclosure. [Figure 2] FIG. 1 is a perspective view of an embodiment of a vapor compression system according to an aspect of the present disclosure. [Figure 3] 1 is a schematic diagram of an embodiment of a vapor compression system according to an aspect of the present disclosure. [Figure 4] 1 is a schematic diagram of an embodiment of a vapor compression system according to an aspect of the present disclosure. [Figure 5]FIG. 1 is a cross-sectional side view of an embodiment of a compressor of a vapor compression system illustrating a bearing system of the compressor according to one aspect of the present disclosure. [Figure 6] 1 is a schematic diagram of an embodiment of a vapor compression system including a bearing system for a compressor, according to an aspect of the present disclosure. [Figure 7] FIG. 1 is a schematic diagram of an embodiment of an accumulator for a bearing system, according to an aspect of the present disclosure. [Figure 8] FIG. 1 is a schematic diagram of an embodiment of an accumulator for a bearing system, according to an aspect of the present disclosure. [Figure 9] FIG. 1 is a schematic diagram of an embodiment of an accumulator for a bearing system, according to an aspect of the present disclosure. [Figure 10] FIG. 1 is a schematic diagram of an embodiment of an accumulator coupled to a fluid tank, according to an aspect of the present disclosure. [Figure 11] FIG. 1 is a schematic diagram of an embodiment of an accumulator for a bearing system, according to an aspect of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0010] One or more specific embodiments are described below. In an effort to provide a concise description of these embodiments, not all features of an actual implementation are described herein. It should be recognized that the development of any such actual implementation, as with any engineering or design project, will require many implementation-specific decisions to be made to achieve the developer's specific goals, which may vary from implementation to implementation, including compliance with system-related and industry-related constraints. Moreover, it should be recognized that such a development effort may be complex and time-consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill in the art having the benefit of this disclosure.

[0011] When introducing elements of various embodiments of the present disclosure, the articles "a," "an," and "the" are intended to mean that there are one or more of the elements. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements other than the listed elements. Additionally, it should be understood that references to "one embodiment" or "an embodiment" of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features.

[0012] As used herein, terms such as "approximately," "generally," and "substantially" are intended to convey, as one skilled in the art would understand, that a described attribute value may fall within a relatively small range of attribute values. For example, when an attribute value is described as being "approximately" equal to (or, e.g., "substantially similar to") a given value, this is intended to mean that the attribute value may be within + / -5%, + / -4%, + / -3%, + / -2%, + / -1% of the given value, or even close to it. Similarly, when a given feature is described as being "substantially parallel" to another feature, "generally perpendicular" to another feature, etc., this is intended to mean that the given feature is within + / -5%, + / -4%, + / -3%, + / -2%, + / -1%, or even close to having the described property, such as being parallel to another feature or perpendicular to another feature. Furthermore, it should be understood that mathematical terms such as "planar," "inclined," "vertical," "parallel," and the like are intended to encompass characteristics of surfaces or elements as understood by those of ordinary skill in the relevant art, and should not be rigorously interpreted as may be understood in the mathematical arts. For example, a "planar" surface is intended to encompass a surface that is machined, molded, or otherwise formed to be substantially flat or smooth (within relevant tolerances) using techniques and tools available to those of ordinary skill in the art. Similarly, a "inclined" surface is intended to encompass a surface that is machined, molded, or otherwise formed to be oriented at an angle (e.g., tilted) relative to a reference point using techniques and tools available to those of ordinary skill in the art.

[0013] Embodiments of the present disclosure relate to a heating, ventilation, air conditioning, and refrigeration (HVAC&R) system (e.g., a chiller) that includes a vapor compression system (e.g., a vapor compression circuit) having a compressor. During operation, the compressor pressurizes a working fluid in the vapor compression system and directs the working fluid to a condenser (e.g., a first heat exchanger), which cools and condenses the working fluid. The condensed working fluid may be directed to an expansion device, which reduces the pressure of the working fluid and further cools the working fluid. From the expansion device, the cooled working fluid may be directed to an evaporator (e.g., a second heat exchanger), where the working fluid is placed in a heat exchange relationship with a conditioned fluid and may cool the conditioned fluid. The conditioned fluid may be circulated between the evaporator and a structure, such as a building, and the conditioned fluid is used to cool an airflow delivered to a conditioned space of the structure. In some embodiments, an air handling unit (AHU) of the HVAC&R system may receive the conditioned fluid from the chiller and utilize the conditioned fluid to cool the airflow delivered to the conditioned space. The conditioning fluid can then be returned to the evaporator and cooled again.

[0014] In some embodiments, a compressor may include a bearing system including bearings (e.g., hydrostatic bearings, porous bearings) that utilize pressurized fluid to support and lubricate the compressor's rotating shaft. For example, the bearing system may include a lubricant circuit extending from the working fluid circuit and directing a portion of the working fluid from the working fluid circuit into the compressor's bearings. That is, a portion of the working fluid (e.g., refrigerant) in the lubricant circuit may be utilized as the lubricating fluid. The lubricant circuit may include a pump configured to pump pressurized fluid toward the compressor's bearings. In this manner, the working fluid configured to exchange heat with a conditioning fluid as part of the working fluid circuit may also be utilized to lubricate the bearings and enable the bearings to support the compressor's shaft. The pump may be configured to maintain a desired pressure of the pressurized fluid supplied to the bearings. Unfortunately, the supply of pressurized fluid to the bearings may sometimes be interrupted or otherwise disrupted. For example, the operation of the pump may be interrupted (e.g., due to a loss of power) or the lubricant circuit may experience a drop in pressure (e.g., due to a blocked or leaky conduit), resulting in a drop in the pressure of the pressurized fluid supplied to the bearings. As a result, compressor operation may be interrupted or limited. Specifically, the shaft may be inadequately supported and / or inadequately lubricated, which may cause unintended operation, wear, and / or deterioration of bearing system components, the compressor shaft, the compressor motor, and / or other components of the vapor compression system. That is, if pump operation is interrupted and the pressure of the pressurized fluid is not properly maintained, the compressor may be susceptible to wear and deterioration caused by uncontrolled shaft momentum, impact forces, and / or friction. Therefore, an improved compressor with a bearing system having a more robust fluid supply system is desired.

[0015] Accordingly, the present embodiments relate to a fluid supply system configured to at least temporarily maintain the pressure of pressurized fluid flowing to a compressor bearing in the event of an interruption in the normal operation of the fluid supply system. Specifically, the fluid supply system described herein includes a pressure accumulator configured to store pressurized fluid (e.g., lubricating fluid) at a desired pressure during normal operation and to discharge (e.g., dispense) the lubricating fluid toward the bearing (e.g., at the desired pressure) during an interruption in normal operation. In this manner, in the event of an interruption in the operation of a pump or other component of the fluid supply system, the pressure accumulator can function as a backup pressure source to continue temporarily supplying a pressurized flow of lubricating fluid to the bearing. Thus, the bearing can receive pressurized lubricating fluid until the pump becomes operational and / or compressor operation is suspended in a controlled manner. In this manner, the present embodiments enable a continuous supply of pressurized lubricating fluid to the bearing (e.g., and allow for controlled shutdown of the compressor, when appropriate) through operation of the pressure accumulator, and enable mitigation of wear and deterioration to the bearing system and compressor components.

[0016] Referring now to the drawings, FIG. 1 is a perspective view of one embodiment of a heating, ventilation, air conditioning, and / or refrigeration (HVAC&R) system 10 within a building 12 for a typical commercial environment. The HVAC&R system may include a vapor compression system 14 that provides cold liquid for cooling the building 12 and a boiler 16 that provides warm liquid for heating the building 12. The vapor compression system 14, also referred to herein as a chiller, may circulate a working fluid (e.g., a refrigerant) that is cooled by a cooling fluid (e.g., a liquid such as water) in a condenser of the vapor compression system 14 and heated by a conditioning fluid (e.g., a liquid such as water) in an evaporator of the vapor compression system 14. The cooling fluid may be provided, for example, by a cooling tower that cools the cooling fluid via ambient air. The conditioning fluid, cooled by the working fluid as described above, may be utilized to cool an airflow provided to a conditioned space of the building 12.

[0017] HVAC&R system 10 may also include an air distribution system that circulates air through building 12. The air distribution system may also include air return ducts 18, air supply ducts 20, and / or air handlers 22. In some embodiments, air handlers 22 may include a heat exchanger connected to boiler 16 and vapor compression system 14 by conduits 24. The heat exchanger within air handler 22 may receive either a warm liquid from boiler 16 or a conditioned fluid (e.g., a cold liquid such as water) from vapor compression system 14, depending on the operating mode of HVAC&R system 10. Although HVAC&R system 10 is shown with a separate air handler for each floor of building 12, in other embodiments, HVAC&R system 10 may include air handlers 22 and / or other components that may be shared between floors.

[0018] 2 and 3 illustrate an embodiment of a vapor compression system 14 or chiller that can be used in HVAC&R system 10. Vapor compression system 14 may circulate a working fluid through a circuit (e.g., a working fluid circuit) that begins with a compressor 32, such as a centrifugal compressor. The circuit may also include a condenser 34, expansion valve(s) or device(s) 36, and an evaporator 38. Vapor compression system 14 may further include a control panel 40 having an analog-to-digital (A / D) converter 42, a microprocessor 44, non-volatile memory 46, and / or an interface board 48.

[0019] Some examples of fluids that can be used as working fluids in vapor compression system 14 include hydrofluorocarbon (HFC) refrigerants, such as R-410A, R-407, R-134a, hydrofluoroolefins (HFOs), ammonia (NH), R-717, carbon dioxide (CO), R-744, or "natural" refrigerants such as hydrocarbon-based refrigerants, water vapor, or any other suitable working fluid. Other possible working fluids include R-123, R-514A, R-1130yd, R-1233zd, R-134a, R-1142ze, R-1142yf, R-1311, R-32, and R-410A. In some embodiments, vapor compression system 14 can be configured to efficiently utilize working fluids with a normal boiling point of approximately 19 degrees Celsius (66 degrees Fahrenheit) at 1 atmosphere, also referred to as low-pressure refrigerants, compared to medium-pressure working fluids such as R-134a. As used herein, "normal boiling point" may refer to the boiling point temperature measured at 1 atmosphere pressure.

[0020] In some embodiments, the vapor compression system 14 may use one or more of a variable speed drive (VSD) 52, a motor 50, a compressor 32, a condenser 34, an expansion valve or device 36, and / or an evaporator 38. The motor 50 may drive the compressor 32 during normal operation and may be powered by the variable speed drive (VSD) 52. The VSD 52 receives alternating current (AC) power during normal operation, where the AC power includes a particular constant line voltage and constant line frequency from an AC power source, and provides power having a variable voltage and frequency to the motor 50. In other embodiments, the motor 50 may be powered directly from an AC or direct current (DC) power source. The motor 50 may include any type of electric motor that can be powered by a VSD or directly from an AC or DC power source, such as a switched reluctance motor, an induction motor, an electronically commutated permanent magnet motor, or another suitable motor.

[0021] The compressor 32 compresses a working fluid vapor and delivers the vapor to the condenser 34 through a discharge passage. In some embodiments, the compressor 32 may be a centrifugal compressor. The working fluid vapor delivered by the compressor 32 to the condenser 34 may transfer heat to a cooling fluid (e.g., water or air) in the condenser 34. The working fluid vapor may condense into a working fluid liquid in the condenser 34 as a result of the heat transfer with the cooling fluid. The liquid working fluid from the condenser 34 may flow through an expansion device 36 to an evaporator 38. In the illustrated embodiment of FIG. 3 , the condenser 34 is water-cooled and includes a tube bundle 54 connected to a cooling tower 56 that supplies cooling fluid to the condenser 34.

[0022] The liquid working fluid delivered to the evaporator 38 may absorb heat from a conditioning fluid that is then sent to a load 62 (e.g., the building 12 of FIG. 1 ). For example, the conditioning fluid may be cooled by the working fluid in the evaporator 38 and then utilized in the building 12 of FIG. 1 to condition the airflow provided to condition the space within the building 12. The liquid working fluid in the evaporator 38 may undergo a phase change from a liquid working fluid to a working fluid vapor. As shown in the illustrated embodiment of FIG. 3 , the evaporator 38 may include a tube bundle 58 having a supply line 60S and a return line 60R connected to the cooling load 62. The conditioning fluid of the evaporator 38 (e.g., water, ethylene glycol, calcium chloride brine, sodium chloride brine, or any other suitable fluid) enters the evaporator 38 via the return line 60R and exits the evaporator 38 via the supply line 60S. The evaporator 38 may reduce the temperature of the conditioning fluid in the tube bundle 58 through heat transfer with the working fluid. The tube bundle 58 in the evaporator 38 may include multiple tubes and / or multiple tube bundles. In either case, the vapor working fluid exits the evaporator 38 and returns to the compressor 32 via a suction line to complete the cycle.

[0023] FIG. 4 is a schematic diagram of one embodiment of the vapor compression system 14 having an intermediate circuit 64 incorporated between the condenser 34 and the expansion device 36. The intermediate circuit 64 may have an inlet line 68 directly fluidly connected to the condenser 34. In other embodiments, the inlet line 68 may be indirectly fluidly coupled to the condenser 34. As shown in the illustrated embodiment of FIG. 4, the inlet line 68 includes a first expansion device 66 positioned upstream of an intermediate vessel 70. In some embodiments, the intermediate vessel 70 may be a flash tank (e.g., a flash intercooler). In other embodiments, the intermediate vessel 70 may be configured as a heat exchanger or a “surface economizer.” In the illustrated embodiment of FIG. 4, the intermediate vessel 70 is used as a flash tank, and the first expansion device 66 is configured to reduce the pressure of (e.g., expand) the liquid working fluid received from the condenser 34. During the expansion process, a portion of the liquid working fluid may vaporize; therefore, intermediate vessel 70 may be used to separate the vapor working fluid received from first expansion device 66 from the liquid working fluid. Additionally, intermediate vessel 70 may provide further expansion of the liquid working fluid due to the drop in pressure the liquid working fluid experiences as it enters intermediate vessel 70 (e.g., due to the sudden increase in volume it experiences as it enters intermediate vessel 70). The vapor working fluid in intermediate vessel 70 may be drawn by compressor 32 through a suction line 74 of compressor 32. In other embodiments, the vapor working fluid in intermediate vessel 70 may be drawn into an intermediate stage (e.g., rather than the suction stage) of compressor 32. The liquid working fluid collecting in intermediate vessel 70 may have a lower enthalpy than the liquid working fluid exiting condenser 34 due to the expansion of the working fluid in expansion device 66 and / or intermediate vessel 70. The liquid working fluid from intermediate vessel 70 may then flow through line 72 and through second expansion device 36 to evaporator 38 .

[0024] According to this embodiment, the compressor 32 may be a centrifugal compressor (e.g., a hermetic compressor) having a floating rotor or shaft. To this end, the vapor compression system 14 includes a bearing system with one or more bearings configured to support the load of the shaft of the compressor 32. The bearing system is configured to direct a pressurized fluid (e.g., a liquid, working fluid, refrigerant) through the bearing, and the bearing is configured to discharge the fluid toward and against the shaft, allowing the shaft to float within the compressor 32. Specifically, the bearing includes one or more porous bearing elements configured to receive and direct the pressurized fluid toward the shaft within the housing of the compressor 32. In this manner, the bearing system may support the load on the shaft and enable the shaft to rotate within the housing of the compressor 32 during operation of the vapor compression system 14. As discussed herein, the pressurized fluid may be a portion of the working fluid (e.g., a refrigerant) circulating through the vapor compression system 14. Accordingly, the vapor compression system 14 may not utilize a dedicated lubricant, such as oil, to support and enable rotation of the shaft of the compressor 32. Additionally, the bearing system may incorporate reduced cost vapor compression system 14 compared to other existing bearing system designs. The disclosed embodiments also allow for improved (e.g., simplified) control of the bearing system as well as more efficient operation of vapor compression system 14.

[0025] With the foregoing in mind, FIG. 5 is a cross-sectional side view of one embodiment of a compressor 32 including a bearing system 100 in accordance with aspects of the present disclosure. The compressor 32 may include a housing 102 and a shaft 104 extending through the housing 102. The compressor 32 may also include an impeller 106 coupled to the shaft 104, such as via a fastener 108. During operation of the compressor 32, the shaft 104 may rotate (e.g., via operation of the motor 50), causing rotation of the impeller 106. The rotation of the impeller 106 may drive a working fluid (e.g., refrigerant) to flow through a working fluid flow path 110 (e.g., from the evaporator 38, from the intermediate vessel 70, the working fluid circuit), drawing the working fluid into the housing 102 via an intake 112 and toward the impeller 106. The impeller 106 may impart mechanical energy to the working fluid and may discharge the working fluid into a diffuser passage 114 of the compressor 32. The working fluid may be channeled from the diffuser passage 114 to a volute 116 of the compressor 32 and from the volute 116 to a condenser (e.g., condenser 34) for heat exchange with a fluid, such as a cooling fluid.

[0026] In the illustrated embodiment, compressor 32 (e.g., bearing system 100) includes a first bearing 118 (e.g., a radial bearing, a bearing assembly, a porous bearing) and a second bearing 120 (e.g., a radial bearing, a bearing assembly, a porous bearing) configured to control and / or adjust the position (e.g., radial position) of shaft 104 relative to an axis 122 (e.g., a rotational axis, a central axis) of shaft 104. For example, first bearing 118 and second bearing 120 may be configured to support a load of shaft 104 such that shaft 104 floats within first bearing 118 and second bearing 120. First bearing 118 and second bearing 120 may also be configured to prevent shaft 104 from moving laterally (e.g., bending, moving radially, rotating eccentrically) relative to axis 122. Compressor 32 (e.g., bearing system 100) further includes a third bearing 124 (e.g., a thrust bearing, an axial bearing, a bearing assembly, a porous bearing) configured to control and / or adjust the position (e.g., axial position) of shaft 104 along axis 122. For example, third bearing 124 may be configured to prevent or limit movement (e.g., translation) of shaft 104 along axis 122.

[0027] As described above, bearing system 100 is configured to direct pressurized fluid to bearings of bearing system 100, such as first bearing 118, second bearing 120, and / or third bearing 124. The pressurized fluid may be the same working fluid (e.g., refrigerant) circulated through vapor compression system 14 having compressor 32. However, it should be appreciated that the pressurized fluid may be any suitable fluid (e.g., refrigerant, condensable vapor, or other fluid). In some embodiments, first bearing 118, second bearing 120, and / or third bearing 124 each include one or more porous elements 126 configured to direct the pressurized fluid therethrough. For example, one or more porous elements 126 of first bearing 118 and second bearing 120 may be configured to receive pressurized fluid and direct the pressurized fluid toward shaft 104, establishing a high-pressure fluid film (e.g., a vapor film) around shaft 104 between first bearing 118, second bearing 120, and shaft 104. In this manner, the pressurized fluid may lift the shaft 104 off the first bearing 118 and the second bearing 120, thereby enabling desired rotation of the shaft 104 about the axis 122. One or more porous elements 126 of the third bearing 124 may receive and direct the pressurized fluid toward a collar 128 (e.g., a thrust collar) of the third bearing 124. In this manner, the pressurized fluid may apply a force to the collar 128 to enable adjustable positioning of the shaft 104 along the axis 122.

[0028] The bearing system 100 includes a fluid supply system 130 configured to supply pressurized fluid to the bearings (first bearing 118, second bearing 120, and / or third bearing 124) of the bearing system 100. For example, the fluid supply system 130 may direct the pressurized fluid through the housing 102 of the compressor 32 to one or more bearing housings 132 (e.g., casings) of the first bearing 118, second bearing 120, and third bearing 124. In the illustrated embodiment, one bearing housing 132 is associated with the first bearing 118 and another bearing housing 132 is associated with the second bearing 120. An additional bearing housing 132 may be utilized for the third bearing 124. In other embodiments, the second bearing 120 and the third bearing 124 may be packaged together within a common bearing housing 132. The pressurized fluid may be directed through the bearing housings 132 to corresponding porous elements 126 retained within each bearing housing 132. The fluid supply system 130 is described in further detail below. It should be appreciated that the compressor 32 may include any suitable number or type of bearings (e.g., axial bearings, radial bearings) incorporating the present technology, and that these bearings may be positioned in any suitable location within the housing 102 of the compressor 32.

[0029] 6 is a schematic diagram of one embodiment of a vapor compression system 14 (e.g., an HVAC&R system) including a bearing system 100 for a compressor 32. The vapor compression system 14 includes similar elements as discussed above, including the compressor 32, a motor 50, a condenser 34, and an evaporator 38 (e.g., a falling film evaporator) arranged along a working fluid circuit 200 (e.g., a refrigerant circuit). In accordance with the present technique, the bearing system 100 also includes a fluid supply system 130 configured to direct pressurized fluid to a bearing (e.g., a first bearing 118) of the bearing system 100. Specifically, the fluid supply system 130 is configured to direct a portion of the working fluid (e.g., refrigerant) circulated through the working fluid circuit 200 to one or more bearing assemblies 150 (e.g., the first bearing 118, the second bearing 120). To this end, the fluid supply system 130 includes a lubricant circuit 202 (eg, a fluid supply circuit) that extends from the actuation fluid circuit 200 to the bearing assembly 150 via a fluid conduit 203 .

[0030] In the illustrated embodiment, lubricant circuit 202 extends from liquid line portion 204 of working fluid circuit 200 to bearing assembly 150. Liquid line portion 204 extends from condenser 34 to evaporator 38. Thus, the working fluid in liquid line portion 204 may be in a liquid phase. Various components are disposed along lubricant circuit 202 and configured to enable a desired supply of working fluid to bearing assembly 150 to enable bearing assembly 150 to support the load of shaft 104 of compressor 32. For example, fluid supply system 130 includes pump 206 (e.g., a liquid pump) disposed along lubricant circuit 202 and configured to direct a flow of working fluid (e.g., liquid working fluid) along lubricant circuit 202 from liquid line portion 204 of working fluid circuit 200 to bearing assembly 150 of motor 50 (e.g., compressor 32). The pump 206 may be a linear piston pump in some embodiments, and the pump 206 may be driven electrically, pneumatically, mechanically, electromechanically, and / or via another suitable technique. In some embodiments, the pump 206 may operate without utilizing oil or other dedicated lubricants.

[0031] Fluid supply system 130 also includes a pressure accumulator 208 fluidly coupled to lubricant circuit 202. Pressure accumulator 208 is fluidly coupled to lubricant circuit 202 (e.g., conduit 203) downstream of pump 206 and / or upstream of bearing assembly 150 with respect to the flow of working fluid along lubricant circuit 202. Thus, pressure accumulator 208 may receive a pressurized flow of working fluid (e.g., liquid working fluid, vapor working fluid, or both) from pump 206 and lubricant circuit 202. As will be appreciated, pressure accumulator 208 is configured to store the pressurized working fluid therein. For example, pressure accumulator 208 may include a container 210 and a separator 212 (e.g., a bladder, a diaphragm, a piston, etc.) disposed therein. In some embodiments, the separator 212 may divide the interior volume of the vessel 210 into a biasing chamber 214 (e.g., a gas chamber) on a first side of the separator 212 and a fluid chamber 216 (e.g., a liquid chamber, a working fluid chamber) on a second side of the separator 212. The fluid chamber 216 of the pressure accumulator 208 is configured to receive pressurized working fluid from the lubricant circuit 202. The separator 212 may be a bladder or other flexible container pre-loaded with a gas (e.g., nitrogen) to enable maintaining the pressure of the working fluid in the fluid chamber 216. In other embodiments, the biasing chamber 214 may be pre-loaded with a gas. In still further embodiments, the biasing chamber 214 may instead include a spring or other mechanical biasing component. In either case, pressure accumulator 208 may operate as a mechanical battery configured to enable the supply (e.g., temporary supply) of pressurized working fluid from fluid chamber 216 to bearing assembly 150 via lubricant circuit 202, such as during periods of non-operation of pump 206. For example, if the flow of working fluid in conduit 203 experiences a change in pressure (e.g., due to an interruption in operation of pump 206), pressure accumulator 208 may distribute (e.g., discharge) pressurized working fluid to lubricant circuit 202 for supply to bearing assembly 150.In this manner, bearing assembly 150 may continue to operate to support a load on shaft 104 while operation of pump 206 is resumed and / or operation of compressor 32 (e.g., motor 50) is stopped in a controlled manner. In some embodiments, pressure accumulator 208 may also operate to regulate (e.g., damp) oscillations in the flow of compressed working fluid directed to bearing assembly 150. Additionally, pressure accumulator 208 may be configured to supply compressed working fluid to bearing assembly 150 upon start-up of vapor compression system 14 (e.g., prior to operation of pump 206 and / or compressor 32). In either case, pressure accumulator 208 may be configured to regulate the flow of working fluid based on the pressure of the flow in conduit 203.

[0032] Fluid supply system 130 may also include other components disposed along lubricant circuit 202, such as a check valve 218 disposed between pump 206 and pressure accumulator 208. Check valve 218 may be configured to shut off and interrupt the flow of liquid working fluid from pump 206 along bearing assembly 150 based on the pressure of the liquid working fluid discharged by pump 206. For example, check valve 218 may close in response to the pressure of the liquid working fluid dropping below a threshold value (e.g., a threshold value corresponding to a liquid working fluid pressure desired to be supplied to bearing assembly 150). In such an event, pressurized liquid working fluid stored in pressure accumulator 208 (e.g., with check valve 218 closed and preventing working fluid from returning to pump 206) may be supplied to bearing assembly 150, enabling at least temporary continuous operation of bearing assembly 150 and supporting shaft 104. Check valve 218 may be a ball check valve, a diaphragm check valve, a swing check valve, a stop check valve, a lift check valve, an in-line check valve, or any other suitable valve.

[0033] In some embodiments, fluid supply system 130 may include a filter 220 disposed along lubricant circuit 202 (e.g., downstream of pressure accumulator 208 and upstream of bearing assembly 150). Filter 220 may be configured to remove particulates and / or moisture (e.g., water, water vapor) from the liquid working fluid (e.g., before the liquid working fluid is directed to bearing assembly 150).

[0034] Fluid supply system 130 may also include a heat exchanger 222 disposed along lubricant circuit 202. Heat exchanger 222 is disposed upstream of pump 206 with respect to the flow of working fluid through lubricant circuit 202. In some embodiments, heat exchanger 222 may be a brazed plate heat exchanger. During operation, heat exchanger 222 may function as a subcooler configured to subcool working fluid channeled into lubricant circuit 202 from liquid line portion 204. In this manner, heat exchanger 222 may operate to ensure that the working fluid supplied to pump 206 is in a liquid phase, which may reduce undesirable effects such as flashing of the working fluid in pump 206 and cavitation of pump 206. Heat exchanger 222 is configured to place the working fluid drawn from liquid line portion 204 in a heat exchange relationship with a cooling fluid (e.g., a supplemental cooling fluid) channeled to heat exchanger 222 via cooling fluid circuit 224. In some embodiments, the cooling fluid may be water. In such embodiments, the cooling fluid circuit 224 may be configured to supply cooling fluid from an external source. Additionally or alternatively, the cooling fluid circuit 224 may be configured to supply water or other cooling fluid (e.g., cooled via the evaporator 38) from a conditioned fluid conduit, such as the supply line 60S and / or the return line 60R described above. In some embodiments, the cooling fluid may be another portion of the working fluid from the working fluid circuit 200. In such embodiments, the cooling fluid circuit 224 may extend from the working fluid circuit 200 (e.g., the liquid line portion 204) to the heat exchanger 222. However, it should be appreciated that the cooling fluid circuit 224 may be configured to direct any suitable cooling fluid to the heat exchanger 222 to enable cooling (e.g., sub-cooling) of a portion of the working fluid directed along the lubricant circuit 202 toward the bearing assembly 150 of the compressor 32.

[0035] As described above, bearing assemblies 150 are configured to receive pressurized fluid (e.g., working fluid, refrigerant) and discharge the fluid toward shaft 104 or collar 128. Specifically, bearing assemblies 150 each include one or more porous elements configured to channel the compressed working fluid, flash the compressed working fluid, and discharge the compressed vapor working fluid toward shaft 104 or collar 128. The working fluid may then flow through housing 102 of compressor 32 (e.g., motor 50) to one or more drain lines 226 of bearing system 100. For example, bearing system 100 may include a first drain line 228 extending from housing 102 to liquid line portion 204 of working fluid circuit 200. First drain line 228 may include a valve 230 (e.g., an electronic expansion valve) and / or be configured to channel the vapor working fluid from housing 102 to liquid line portion 204 of working fluid circuit 200. Additionally or alternatively, the bearing system 100 may include a second drain line 232 extending from the housing 102 to the evaporator 38 and / or a third drain line 234 extending from the housing 102 to the evaporator 38. In some embodiments, the second drain line 232 is configured to conduct the vapor working fluid from the housing 102 to the evaporator 38, and the third drain line 234 is configured to conduct the liquid working fluid from the housing 102 to the evaporator 38.

[0036] The vapor compression system 14 may also include a controller 250 (e.g., a control system, control board, control panel) communicatively coupled to one or more components of the vapor compression system 14 and / or bearing system 100. The controller 250 is configured to monitor, regulate, and / or otherwise control the operation of the components of the vapor compression system 14 and / or bearing system 100. One or more control transfer devices, such as, for example, wires, cables, wireless communication devices, etc., may communicatively couple the compressor 32, the motor 50, the pump 206, and / or other components described herein. Such components may include network interfaces that enable the components of the vapor compression system 14 and / or bearing system 100 to communicate via various protocols, such as Ethernet / IP, ControlNet, DeviceNet, or any other communication network protocol. Alternatively, the communication components may enable the components of the vapor compression system 14 and / or bearing system 100 to communicate via mobile communication technology, Bluetooth, near-field communication technology, etc.

[0037] In some embodiments, controller 250 may comprise part or all of control panel 40, or may be another suitable controller included in vapor compression system 14 and / or bearing system 100. In either case, controller 250 may be configured to control components of vapor compression system 14 and / or bearing system 100 in accordance with the technology discussed herein. Controller 250 includes processing circuitry 252, such as one or more microprocessors, which may execute software for controlling the components of vapor compression system 14 and / or bearing system 100. Processing circuitry 252 may include multiple microprocessors, one or more “general-purpose” microprocessors, one or more special-purpose microprocessors, and / or one or more application-specific integrated circuits (ASICs), or some combination thereof. For example, processing circuitry 252 may include one or more reduced instruction set (RISC) processors.

[0038] Controller 250 may also include a memory device 254 (e.g., memory) that may store information such as instructions, control software, look-up tables, configuration data, etc. Memory device 254 may include volatile memory (e.g., random access memory (RAM)) and / or non-volatile memory (e.g., read-only memory (ROM)). Memory device 254 may store a variety of information and may be used for a variety of purposes. For example, memory device 254 may store processor-executable instructions, including firmware or software, for execution by processing circuit 252, such as instructions for controlling components of vapor compression system 14 and / or bearing system 100. In some embodiments, memory device 254 is a tangible, non-transitory, machine-readable medium that may store machine-readable instructions for execution by processing circuit 252. Memory device 254 may include ROM, flash memory, a hard drive, or any other suitable optical, magnetic, or solid-state storage medium, or a combination thereof. Memory device 254 may store data, instructions, and any other suitable data. It should be appreciated that memory device 254 may store processor-executable instructions (e.g., for execution via processing circuitry 252) for controlling any of the components described herein to enable any or all of the operations and / or functions described herein.

[0039] Controller 250 may be configured to control operation of components of vapor compression system 14 and / or bearing system 100 based on detected operating parameters of vapor compression system 14 and / or bearing system 100. To this end, vapor compression system 14 includes one or more sensors 256 configured to detect operating parameters associated with or indicative of the operating state of vapor compression system 14 and bearing system 100. For example, one or more of sensors 256 may be disposed along lubricant circuit 202 and configured to detect operating parameters such as the temperature, pressure, flow rate, etc. of refrigerant channeled through lubricant circuit 202. In some embodiments, one or more sensors 256 may be configured to detect operating parameters associated with motor 50, such as the rotational speed of shaft 104, torque on shaft 104, the temperature of motor 50, etc. As described further below, one or more sensors 256 may be configured to detect operating parameters of bearing assembly 150, such as detecting whether one or more bearing assemblies 150 are in contact (e.g., physical contact) with shaft 104.

[0040] In some embodiments, one of sensors 256 may be configured to detect an operating parameter, such as the pressure of a refrigerant in fluid chamber 216 and / or the pressure of a gas in biasing chamber 214, associated with pressure accumulator 208. Additionally or alternatively, one or more of sensors 256 may be configured to detect a level of working fluid in condenser 34, which may be referenced prior to and / or during start-up of bearing system 100 and / or vapor compression system 14. As will be appreciated, each sensor 256 included in vapor compression system 14 may be communicatively coupled to controller 250. Thus, controller 250 may receive data and / or feedback from sensors 256 and may control the operation of vapor compression system 14 and / or bearing system 100 based on this feedback and / or data.

[0041] 7 is a schematic diagram of one embodiment of pressure accumulator 208, illustrating pressure accumulator 208 as a spring-loaded piston accumulator 300. As discussed above, fluid conduit 203 transports a pressurized flow 302 of working fluid from pump 206 to bearing system 100. A fluid port 304 of spring-loaded piston accumulator 300 may be fluidly coupled to fluid conduit 203, such that spring-loaded piston accumulator 300 is configured to receive a portion of pressurized flow 302 of working fluid. Spring-loaded piston accumulator 300 includes a piston 306 driven by a spring 308. Piston 306 and spring 308 are disposed within a reservoir 210 of accumulator 208. The spring 308 applies a spring force to one side of the piston 306 to balance the piston 306 against a fluid pressure 310 of the hydraulic fluid acting on the other (e.g., opposite) side of the piston 306. Thus, as the hydraulic fluid enters the fluid chamber 216, the fluid pressure 310 may act against the piston 306, compressing the spring 308. In this manner, the spring-loaded piston accumulator 300 may store hydraulic fluid in the fluid chamber 216 while the spring 308 and piston 306 apply a balancing pressure to the hydraulic fluid stored in the fluid chamber 216.

[0042] In some circumstances, the pressurized flow 302 of working fluid through the check valve 218 may fall below a threshold or desired pressure level. For example, operation of the pump 206 may be interrupted (e.g., due to a loss of power), the fluid conduit 203 may experience a blockage or leak upstream of the spring-loaded piston accumulator 300, or the pressurized flow 302 may be reduced or stopped by a valve (e.g., an emergency shut-off valve) upstream of the check valve 218. The pressure accumulator 208 may discharge pressurized working fluid stored in the fluid chamber 216 into the fluid conduit 203 and toward the bearings to temporarily maintain a supply of pressurized working fluid to the bearings of the bearing system 100. In particular, the force of the spring 308 acting on the piston 306 may cause the spring-loaded piston accumulator 300 to release the stored working fluid from the fluid chamber 216 into the fluid conduit 203 (e.g., via the fluid port 304). In this manner, the pressure accumulator 208 may maintain a supply of pressurized working fluid to the bearings until the lubricant circuit 202 (e.g., fluid supply system 130) returns to normal operation and / or the compressor 32 (e.g., shaft 104) shuts off.

[0043] In response to a loss of pressure (e.g., in fluid chamber 216, in fluid conduit 203), check valve 218 may close to prevent working fluid discharged from pressure accumulator 208 from proceeding upstream toward pump 206. In some embodiments, to open check valve 218 and allow pressurized flow 302 of working fluid to flow therethrough, the pressure upstream of check valve 218 must be greater than the pressure downstream of check valve 218. For example, check valve 218 may be a swing check valve configured to allow fluid to flow therethrough in response to the pressure (e.g., pressure differential) of the downstream flow exceeding a threshold pressure (e.g., cracking pressure). Alternatively, sensor 256 may detect that the pressure upstream of check valve 218, the pressure downstream of check valve 218, and / or the pressure in fluid chamber 216 is lower than the threshold pressure. The controller 250 may then direct the check valve 218 to close, thereby avoiding backflow of the working fluid. In some embodiments, the check valve 218 may be configured to close in response to detecting backpressure across the check valve 218.

[0044] FIG. 8 is a schematic diagram of one embodiment of the pressure accumulator 208, illustrating the pressure accumulator 208 as a gas-filled piston accumulator 320. Like the spring-loaded piston accumulator 300 discussed above with reference to FIG. 7, the gas-filled piston accumulator 320 includes a piston 322 configured to apply a balancing pressure against the fluid pressure 310 of the working fluid within the fluid chamber 216. The gas-filled piston accumulator 320 includes a gas chamber 324 (e.g., bias chamber 214) on a side of the piston 322 opposite the fluid chamber 216. A pressurized gas 326 (e.g., a gas charge, an inert gas, a precharge gas, nitrogen) may be introduced into the gas chamber 324 via a charge valve 328 fluidly coupled to the gas chamber 324. For example, the gas chamber 324 may be charged with nitrogen to a desired pressure prior to operation of the gas-filled piston accumulator 320. Gas 326 in gas chamber 324 exerts a gas pressure 330 on piston 322, which acts or biases against fluid pressure 310 exerted by the working fluid. During normal operation, gas pressure 330 and fluid pressure 310 may be balanced so that piston 322 is in an equilibrium position. However, if fluid pressure 310 drops (e.g., during an interruption in operation of pump 206), check valve 218 may close and gas pressure 330 may push against piston 322, expelling working fluid from fluid chamber 216 to maintain pressurized flow 302 of working fluid to the bearings.

[0045] FIG. 9 is a schematic diagram of pressure accumulator 208, illustrating pressure accumulator 208 as a bladder accumulator 340. Bladder accumulator 340 includes a fluid chamber 342 and a bladder 344 housed within a container 346. Fluid chamber 346 is fluidly coupled to fluid conduit 203 via fluid port 348, such that pressurized flow of working fluid 302 may enter fluid chamber 342 via fluid port 348. Bladder 344 may be a gas chamber having one or more walls 350 formed from an elastomeric material. The shape and / or volume of bladder 344 may change in response to a pressure differential across wall 350 of bladder 344 (e.g., between the interior and exterior). Pressurized gas 352 may be introduced into bladder 344 via fill port 354 to achieve a pre-fill state of bladder 344 prior to operation of bladder accumulator 340. The pressurized gas 352 exerts a gas pressure 356 on the wall 350 of the bladder 344, causing the bladder 344 to expand into the fluid chamber 342. In the pre-filled state, the bladder 344 may expand to completely fill the vessel 346 (e.g., occupy substantially the entire volume of the vessel 346). When the bladder accumulator 340 is fluidly coupled to the fluid conduit 203, a pressurized flow 302 of working fluid may enter the fluid chamber 342 via the fluid port 348 and exert a fluid pressure 358 against the wall 350 of the bladder 344, causing the bladder to contract. In this manner, the respective volumes of the bladder 344 and the fluid chamber 342 may vary depending on the pressure of the pressurized gas 352 and the working fluid within the fluid chamber 342.

[0046] During normal operation, working fluid may accumulate in the fluid chamber 342 at a pressure corresponding to the pressure of the pressurized flow 302 of working fluid directed to the bearing. As a result, when fluid pressure 358 acts on the wall 350 of the bladder 344, the bladder 344 may store gas pressure 356 in a contracted state. Thus, the shape and volume of the bladder 356 may be in equilibrium with the fluid chamber 342. However, if the fluid pressure 358 drops (e.g., during an interruption in the operation of the pump 206), the check valve 218 may close and the gas pressure 356 may expand the bladder 344, thereby displacing working fluid from the fluid chamber 342 and maintaining the pressurized flow 302 of working fluid to the bearing.

[0047] In some embodiments, the bladder accumulator 340 may include a poppet valve 360 ​​at the fluid port 348. The poppet valve 360 ​​may be biased (e.g., spring-loaded) toward an open position to allow hydraulic fluid to flow into and out of the fluid chamber 342. When the bladder 344 is in a fully expanded (e.g., pre-filled) state, the bladder 344 may abut against and bias the poppet valve 360, thereby closing the poppet valve 260 and preventing the bladder 344 from expanding out of the fluid port 348 and into the fluid conduit 203.

[0048] As the bladder 344 expands and provides backup pressure for the working fluid, the gas pressure 356 may decrease. Thus, the pressure of the working fluid supplied to the bearing from the bladder accumulator 340 may decrease over time. It may be desirable to maintain a relatively constant pressure of the working fluid exiting the bladder 344. To this end, the bladder accumulator 340 may be fluidly coupled to a fluid source (e.g., a gas source).

[0049] For example, FIG. 10 is a schematic diagram of one embodiment of a bladder accumulator 340, illustrating the bladder accumulator 340 coupled to a fluid source 370 (e.g., a gas supply, gas tank, gas reservoir). The fluid source 370 is configured to introduce gas 352 into the bladder 344 (e.g., within an interior volume defined by the wall 350) to maintain an elevated gas pressure 356 during expansion of the bladder 344 (e.g., during exhaustion of working fluid from the bladder accumulator 304). Because the change in volume of the bladder 344 may be relatively small compared to the combined volume of the container 346 and the fluid source 370 (e.g., a gas tank), the gas pressure 356 may remain relatively constant as the bladder 344 expands. In this manner, the pressure of the working fluid supplied from the bladder accumulator 340 to the bearing may be relatively constant throughout the expansion of the bladder 344.

[0050] FIG. 11 is a schematic diagram of one embodiment of the pressure accumulator 208, illustrating the pressure accumulator 208 as a diaphragm accumulator 380. The diaphragm accumulator 380 includes a fluid chamber 382 and a gas chamber 384 housed within a container 388 and separated by a diaphragm 386. The diaphragm 386 may be formed from an elastomeric material (e.g., rubber) and configured to expand toward one or both of the fluid and gas chambers 382 and 384 based on a pressure differential between the chambers. For example, pressurized gas 390 may be introduced into the gas chamber 384 via a fill port 392 to achieve a pre-charge state prior to operation of the diaphragm accumulator 340. The pressurized gas 390 may exert a gas pressure 394 against the diaphragm 386, thereby expanding the diaphragm 386 toward the fluid chamber 382. Thus, the volume of gas chamber 284 may increase and the volume of fluid chamber 382 may decrease. In the pre-filled state, diaphragm 386 may extend to completely block fluid chamber 382. When diaphragm accumulator 380 is fluidly coupled to fluid conduit 203, pressurized flow 302 of actuating fluid may enter fluid chamber 382 through fluid port 396 and exert fluid pressure on diaphragm 386, expanding fluid chamber 382 and contracting gas chamber 384.

[0051] During normal operation, hydraulic fluid may accumulate in the fluid chamber 382 at a fluid pressure corresponding to the pressure of the pressurized flow of hydraulic fluid 302. As a result, the diaphragm accumulator 380 may store the pressure differential across the diaphragm 386. In some cases, the shape and volume of the gas chamber 384 may be in equilibrium with the fluid chamber 382. However, if the fluid pressure drops (e.g., during an interruption in the operation of the pump 206), the check valve 218 may close and the gas pressure 394 may cause the diaphragm 386 to bulge toward the fluid port 396, thereby expelling hydraulic fluid from the fluid chamber 382 and maintaining the pressurized flow of hydraulic fluid 302 to the bearing. To prevent the diaphragm 386 from being forced out of the reservoir 388, the diaphragm accumulator 380 may include a button 398 on the diaphragm 386 or a poppet valve at the fluid port to block the fluid port during expansion and / or actuation of the diaphragm 386.

[0052] In addition to providing a backup source of pressurized working fluid to fluid supply system 130 in the event of interruptions in normal operation, pressure accumulator 208 may regulate the flow of pressurized working fluid during normal operation. For example, the pressure of the working fluid upstream of pressure accumulator 208 may undesirably fluctuate and / or spike (e.g., due to pump cycles). Pressure accumulator 208 may mitigate fluctuations by storing and releasing pressurized working fluid in coordination with changes in the pressure of the working fluid entering fluid chamber 216. Thus, pressure accumulator 208 may act as a mechanical capacitor, smoothing out energy oscillations in the conduits and thereby providing a more consistent pressurized flow of working fluid to the bearings.

[0053] While only certain features and embodiments have been illustrated and described, those skilled in the art may make numerous modifications and changes, such as variations in the size, dimensions, structure, shape, and proportions of various elements, values ​​of parameters such as temperature and pressure, mounting arrangements, use of materials, color, orientation, etc., without substantially departing from the novel teachings and advantages of the subject matter recited in the claims. The order or sequence of any process or method steps may be changed or re-ordered according to alternative embodiments. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes that fall within the true spirit of the present disclosure.

[0054] Moreover, in an effort to provide a concise description of exemplary embodiments, all features of an actual implementation may not be described, such as those that are not relevant to the currently contemplated best mode or that are not relevant to enabling. It should be recognized that, as in any engineering or design project, numerous implementation-specific decisions may be made in the development of any such actual implementation. While such a development effort may be complex and time-consuming, it would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill in the art having the benefit of this disclosure, without undue experimentation.

[0055] The technology presented and claimed herein refers to and applies to material objects and concrete examples of a practical nature that clearly improve the art, and thus is not abstract, intangible, or purely theoretical. Furthermore, if any claim appended at the end of this specification contains one or more elements designated as "means for [performing] [function]" or "step for [performing] [function]," it is intended that such elements be construed under 35 U.S.C. 112(f). However, for any claim containing elements designated in any other manner, it is intended that such elements not be construed under 35 U.S.C. 112(f).

Claims

1. A heating, ventilation, air conditioning, and / or refrigeration (HVAC&R) system comprising: a compressor having a bearing; a lubricant circuit configured to direct fluid flow to the bearing; a pressure accumulator fluidly coupled to the lubricant circuit upstream of the bearing, the pressure accumulator configured to receive and contain a portion of the fluid from the lubricant circuit.

2. The HVAC&R system of claim 1 , wherein the pressure accumulator is configured to apply a force to the portion of the fluid to regulate a pressure of the flow of the fluid within the lubricant circuit.

3. 2. The HVAC&R system of claim 1, wherein the pressure accumulator is configured to supply the portion of the fluid to the bearing in response to a decrease in pressure of the flow of the fluid in the lubricant circuit.

4. The pressure accumulator comprises: a fluid chamber configured to receive and contain the portion of the fluid; 10. The HVAC&R system of claim 1, further comprising: a biasing chamber configured to apply a force to the portion of the fluid.

5. 5. The HVAC&R system of claim 4, wherein the pressure accumulator comprises a separator separating the fluid chamber and the biasing chamber, the biasing chamber configured to contain pressurized gas, the pressurized gas configured to exert the force on the separator.

6. The HVAC&R system of claim 1 , wherein the pressure accumulator comprises a piston configured to apply a force to the portion of the fluid within the pressure accumulator.

7. a pump disposed along the lubricant circuit, the pump configured to pump the flow of the fluid toward the bearing; 10. The HVAC&R system of claim 1, further comprising a check valve disposed along the lubricant circuit between the pump and the pressure accumulator.

8. The HVAC&R system of claim 7 , wherein the pressure accumulator is configured to provide the portion of the fluid to the bearing in response to an interruption in operation of the pump.

9. 10. The HVAC&R system of claim 1, wherein the compressor is configured to circulate a working fluid through a working fluid circuit of the HVAC&R system, and the lubricant circuit is configured to direct a portion of the working fluid from the working fluid circuit to the bearing as the flow of the fluid.

10. A heating, ventilation, air conditioning, and / or refrigeration (HVAC&R) system comprising: a compressor having a bearing; a conduit configured to direct a pressurized flow of fluid to the bearing; a pressure accumulator fluidly coupled to the conduit, the pressure accumulator configured to apply a force to the fluid in the conduit based on a change in pressure of the fluid in the conduit.

11. 11. The HVAC&R system of claim 10, further comprising a pump configured to drive the pressurized flow of the fluid through the conduit, the pump disposed along the conduit, and the pressure accumulator disposed between the pump and the bearing.

12. 12. The HVAC&R system of claim 11, wherein the pressure accumulator is configured to at least partially drive the pressurized flow of the fluid to the bearing in response to an interruption in operation of the pump.

13. 12. The HVAC&R system of claim 11, wherein the pressure accumulator is configured to receive a portion of the pressurized flow of the fluid from the conduit and store the portion of the pressurized flow of the fluid in the pressure accumulator during operation of the pump.

14. The pressure accumulator comprises: a fluid chamber configured to receive a portion of the pressurized flow of the fluid from the conduit; 11. The HVAC&R system of claim 10, comprising: a biasing chamber configured to apply a force to the portion of the pressurized flow of the fluid based on a pressure of the portion of the pressurized flow of the fluid within the fluid chamber.

15. 15. The HVAC&R system of claim 14, wherein the biasing chamber comprises a bladder containing pressurized gas, the bladder configured to expand based on the pressure of the portion of pressurized fluid in the fluid chamber.

16. The HVAC&R system of claim 14 , further comprising a gas reservoir coupled to the pressure accumulator, the gas reservoir configured to supply pressurized gas to the biasing chamber.

17. 11. The HVAC&R system of claim 10, wherein the compressor is configured to circulate a working fluid through a working fluid circuit of the HVAC&R system, and the pressurized flow of the fluid includes a portion of the working fluid.

18. A heating, ventilation, air conditioning, and / or refrigeration (HVAC&R) system comprising: a compressor configured to pressurize a working fluid and circulate the working fluid through a working fluid circuit of the HVAC&R system, the compressor comprising: a bearing; a lubricant circuit extending from the hydraulic fluid circuit to the bearing; a pump disposed along the hydraulic fluid circuit and configured to direct the hydraulic fluid to the bearing; a pressure accumulator fluidly coupled to the lubricant circuit, the pressure accumulator configured to store a pressurized volume of the working fluid.

19. 19. The HVAC&R system of claim 18, wherein the pressure accumulator is configured to supply the pressurized volume of the working fluid to the bearing in response to a change in pressure of the portion of the working fluid in the lubricant circuit.

20. 20. The HVAC&R system of claim 18, wherein the pressure accumulator comprises a diaphragm configured to apply a force to the pressurized volume of the working fluid.

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