This application relates generally to vapor compression systems incorporated in air conditioning and refrigeration applications, and, more particularly, to flow control of refrigerant in a compressor.
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are 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.
Vapor compression systems are utilized in residential, commercial, and industrial environments to control environmental properties, such as temperature and humidity, for occupants of the respective environments. The vapor compression system circulates a working fluid, typically referred to as a refrigerant, which changes phases between vapor, liquid, and combinations thereof in response to being subjected to different temperatures and pressures associated with operation of the vapor compression system. For example, the vapor compression system utilizes a compressor to circulate the refrigerant to a heat exchanger which may transfer heat between the refrigerant and another fluid flowing through the heat exchanger. Unfortunately, in certain conditions, refrigerant flow through the compressor may induce backspin in the compressor, which may cause undesirable wear and degradation on the compressor and related components.
In an embodiment of the present disclosure, a compressor includes a diffuser passage configured to receive refrigerant flow from an impeller of the compressor, where the diffuser passage is at least partially defined by a compressor discharge plate of the compressor. The compressor also includes a variable geometry diffuser positioned within the diffuser passage and configured to adjust a dimension of a refrigerant flow path through the diffuser passage, an actuator coupled to the variable geometry diffuser and configured to adjust a position of the variable geometry diffuser within the diffuser passage, and a controller configured to regulate operation of the actuator. The controller is configured to instruct the actuator to adjust the position of the variable geometry diffuser from a first position to a second position using a first force and to adjust the position of the variable geometry diffuser from the second position to a third position using a second force less than the first force, where the variable geometry diffuser abuts the compressor discharge plate in the third position.
In another embodiment of the present disclosure a heating, ventilation, air conditioning, and refrigeration (HVAC&R) system includes a compressor configured to pressurize refrigerant within a refrigerant circuit, where the compressor includes a diffuser passage configured to receive the refrigerant from an impeller of the compressor. The HVAC&R system also includes a variable geometry diffuser of the compressor, where the variable geometry diffuser is configured to be positioned within the diffuser passage and is configured to adjust a dimension of a refrigerant flow path through the diffuser passage, an actuator configured to adjust a position of the variable geometry diffuser within the diffuser passage, and a controller configured to regulate operation of the actuator, where the controller is configured to control the actuator to position the variable geometry diffuser within the diffuser passage and against a compressor discharge plate during stoppage of the compressor.
In a further embodiment of the present disclosure, a heating, ventilation, air conditioning and refrigeration (HVAC&R) system controller includes a tangible, non-transitory, computer-readable medium storing computer-executable instructions that, when executed, are configured to cause processing circuitry to control an actuator to position a variable geometry diffuser in a diffuser passage of a compressor within a first range of positions during operation of the compressor, control the actuator to position the variable geometry diffuser in the diffuser passage of the compressor within a second range of positions during stoppage of the compressor, and control the actuator to maintain a position of the variable geometry diffuser within the diffuser passage and against a compressor discharge plate of the compressor during stoppage of the compressor.
Various aspects of this disclosure may be better understood upon reading the following detailed description and upon reference to the drawings in which
One or more specific embodiments of the present disclosure will be described below. These described embodiments are examples of the presently disclosed techniques. Additionally, in an effort to provide a concise description of these embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers’ specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.
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.
Embodiments of the present disclosure are directed toward a heating, ventilating, air conditioning, and refrigeration (HVAC&R) system configured to cool a conditioning fluid. For example, the HVAC&R system may receive a flow of the conditioning fluid, such as from air handling equipment or other terminal devices in a building, and cool the conditioning fluid. The HVAC&R system may then return the conditioning fluid to the air handling equipment for use in cooling or conditioning air in the building. The HVAC&R system may include a vapor compression system configured to cool a refrigerant and place the cooled refrigerant in a heat exchange relationship with the conditioning fluid to absorb heat or thermal energy from the conditioning fluid. In general, the vapor compression system includes a refrigerant circuit configured to circulate the refrigerant through one or more heat exchangers, such as a condenser and an evaporator. The vapor compression system also includes a compressor (e.g., centrifugal compressor) to circulate the refrigerant through the refrigerant circuit. In some embodiments, the HVAC&R system is a chiller system, such as a water-cooled chiller system or air-cooled chiller system.
Unfortunately, in certain conditions, the compressor may be susceptible to spin (e.g., backspin) due to flow of the refrigerant through the refrigerant circuit. For example, when operation of a chiller system is suspended, the conditioning fluid (e.g., water) may still flow through the evaporator and/or a cooling fluid (e.g., water) may still flow through the condenser disposed along the refrigerant circuit. The temperature of the water may cause boiling of refrigerant in the condenser and/or condensing of the refrigerant in the evaporator. As a result, natural refrigerant migration through the refrigerant circuit (e.g., from the condenser to the evaporator via the compressor) may be induced, which may cause undesirable spin (e.g., backspin) of the compressor.
The compressor may also be susceptible to spin or backspin via refrigerant flow in embodiments of the chiller system having multiple refrigerant circuits (e.g., in a series counter-flow arrangement), and therefore multiple compressors, when one of the refrigerant circuits is idle or not operating. As will be appreciated, spin or backspin of a non-operating compressor can cause wear and degradation to the motor of the non-operating compressor. Additionally, bearing support systems (e.g., oil pumps, magnetic bearings, etc.) of the non-operating compressor may also be inactive, thereby exposing the non-operating compressor and/or the bearing support systems to premature wear and degradation during instances of compressor spin or backspin. Unfortunately, conventional systems and methods to reduce compressor spin or backspin, such as automated discharge isolation valves, are expensive.
Accordingly, embodiments of the present disclosure are directed to systems and methods for utilizing a variable geometry diffuser (VGD), such as a variable geometry diffuser ring, as a flow check valve to substantially reduce, block, or prevent undesirable refrigerant flow across the compressor and thereby mitigate spin and/or backspin of the compressor. Specifically, present embodiments include an actuator and/or actuation system (e.g., a two-stage actuator) configured to operate in multiple modes to actuate and move the VGD within a diffuser passage of the compressor. For example, the actuator may be configured to operate in a first mode by applying a first force to move the VGD and to operate in a second mode by applying a second force that is less than the first force to move the VGD. In accordance with present techniques, a control system is configured to selectively regulate operation of the actuator between the first mode and the second mode, for example, based on an operational state of the compressor and/or based on a position of the VGD within the diffuser passage. The control system may operate the actuator in the first mode when the compressor is operating in order to move the VGD within the diffuser passage and adjust a size of a flow path (e.g., refrigerant flow path) through the diffuser passage, such as for surge or capacity control of the compressor. The control system may operate the actuator in the second mode when the compressor is not operating, during a fault sequence, and/or during a shutdown sequence in order to move the VGD within the diffuser passage and abut an opposing surface of the diffuser passage, thereby substantially completely blocking or closing the flow path through the diffuser passage. In this way, the VGD may block or prevent refrigerant flow through the compressor so as to reduce spin and backspin of the compressor when the compressor is not operating. Details of the operation of the control system and the actuator are discussed in further detail below.
It should be noted that the disclosure herein describes the present techniques used with a VGD ring of a compressor. However, the present techniques may also be utilized in embodiments of a compressor that utilize other types of VGDs, such as variable vane diffusers, variable wall diffusers, or other types of diffusers. Moreover, the discussion below describes the present techniques implemented in a water-cooled chiller system, but the systems and methods disclosed herein may also be implemented in other HVAC&R systems.
Turning now to the drawings,
Some examples of fluids that may be used as refrigerants in the vapor compression system 14 are hydrofluorocarbon (HFC) based refrigerants, for example, R-410A, R-407, R-134a, hydrofluoro olefin (HFO), “natural” refrigerants like ammonia (NH3), R-717, carbon dioxide (CO2), R-744, or hydrocarbon based refrigerants, water vapor, or any other suitable refrigerant. In some embodiments, the vapor compression system 14 may be configured to efficiently utilize refrigerants having a normal boiling point of about 19° C. (66° F.) at one atmosphere of pressure, also referred to as low pressure refrigerants, versus a medium pressure refrigerant, such as R-134a. As used herein, “normal boiling point” may refer to a boiling point temperature measured at one atmosphere of pressure.
In some embodiments, the vapor compression system 14 may use one or more of a variable speed drive (VSDs) 52, a motor 50, the compressor 32, the condenser 34, the expansion valve or device 36, and/or the evaporator 38. The motor 50 may drive the compressor 32 and may be powered by a variable speed drive (VSD) 52. The VSD 52 receives alternating current (AC) power having a particular fixed line voltage and fixed 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.
The compressor 32 compresses a refrigerant 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 refrigerant 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 refrigerant vapor may condense to a refrigerant liquid in the condenser 34 as a result of thermal heat transfer with the cooling fluid. The liquid refrigerant from the condenser 34 may flow through the expansion device 36 to the evaporator 38. In the illustrated embodiment of
The liquid refrigerant delivered to the evaporator 38 may absorb heat from another cooling fluid (e.g., a conditioning fluid), which may or may not be the same cooling fluid used in the condenser 34. The liquid refrigerant in the evaporator 38 may undergo a phase change from the liquid refrigerant to a refrigerant vapor. As shown in the illustrated embodiment of
As mentioned above, the systems and methods disclosed herein may be utilized in HVAC&R systems 10 and/or vapor compression systems 14 having multiple refrigerant circuits. For example,
In the illustrated embodiment, the first and second refrigerant circuits 82 and 84 of the vapor compression system 14 are arranged in a series counter-flow arrangement. Specifically, the first and second evaporators 38A and 38B define a portion of a conditioning fluid flow path or circuit 86 that extends from a cooling load 88 (e.g., air handlers 22), sequentially through the second evaporator 38B and the first evaporator 38A, and back to the cooling load 88. Similarly, the first and second condensers 34A and 34B define a portion of a cooling fluid flow path or circuit 90 that extends from a cooling fluid source 92 (e.g., cooling tower 56), sequentially through the first condenser 34A and the second condenser 34B, and back to the cooling fluid source 92. Thus, conditioning fluid is directed through the vapor compression system 14 first through the second evaporator 38B and then through the first evaporator 38A, while cooling fluid is directed through the vapor compression system 14 first through the first condenser 34A and then through the second condenser 34B, thereby providing the series counter-flow arrangement.
In some circumstances, one of the refrigerant circuits 80 may be in an operating state, while the other of the refrigerant circuits 80 may be in a non-operating state. As will be appreciated, the compressor 32 of the refrigerant circuit 80 that is not operating may be idle (e.g., the motor 50 associated with the compressor 32 is not powered or energized). Thus, the compressor 32 of the non-operating refrigerant circuit 80 does not operate to circulate refrigerant through the non-operating refrigerant circuit 80. Nevertheless, the non-operating refrigerant circuit 80 may still be susceptible to natural refrigerant migration therethrough. For example, if the first refrigerant circuit 82 is in an operating state and the second refrigerant circuit 84 is in a non-operating state, cooling fluid may still circulate through the second condenser 34B along the cooling fluid circuit 90 (e.g., from the first condenser 34A, through the second condenser 34B, and to the cooling fluid source 92). Similarly, conditioning fluid may still circulate through the second evaporator 38B along the conditioning fluid circuit 86 (e.g., from the cooling load 88, through the second evaporator 38B, and to the first evaporator 38A). In some circumstances, the flow of cooling fluid through the second condenser 34B and/or the flow of conditioning fluid through the second evaporator 38B may induce natural refrigerant migration through the second refrigerant circuit 84. As discussed above, natural refrigerant migration may induce undesirable spin or backspin in the second compressor 32B that is not operating.
Accordingly, present embodiments include a flow control system 94 configured to improve operation and control of the compressor 32, such as by reducing, blocking, and/or preventing undesirable spin and/or backspin of the compressor 32. As described in further detail below, the flow control system 94 may be incorporated with (e.g., integrated with) the compressor 32 (e.g., one or both of compressors 32A, 32B) and may include a variable geometry diffuser (VGD) of the compressor 32, an actuation system configured adjust a position of the VGD within the compressor 32, and a control system configured to control operation of the actuation system. In some applications, the VGD is utilized to adjust a flow path through a diffuser passage of the compressor 32 in order enable surge and/or capacity control of the compressor 32 during operation of the compressor 32. Additionally, the VGD may be controlled via the actuation system and control system to position the VGD within the diffuser passage to completely or substantially completely block the flow path through the diffuser passage by positioning the VGD against an opposing wall of the diffuser passage and thus block refrigerant flow through the diffuser passage when the compressor 32 is not operating. In this way, the VGD may function as a flow check valve to mitigate or reduce spin and/or backspin of the compressor 32 that may be caused by natural refrigerant migration when the compressor 32 is not operating. As discussed in further detail below, the actuation system is configured to move the VGD within the diffuser passage for capacity and/or surge control using a first force and to move the VGD within the diffuser passage to abut the opposing surface and completely block the flow path through the diffuser passage using a second force that is less than the first force.
As noted above, the compressor 32 may include the flow control system 94 to regulate refrigerant flow through the compressor 32. The flow control system 94 may include a variable geometry diffuser (VGD) 110 disposed in, or proximate to, a lower portion of the diffuser passage 106 (e.g., between the impeller 104 and the collector 108 and proximate the impeller 104), an actuator 112, and a controller 114 (e.g., a control system). For example, the VGD 110 may be positioned at least partially within or adjacent the nozzle base plate 109 (e.g., within a groove formed in the nozzle base plate 109). In the illustrated embodiment, the VGD 110 is a VGD ring. However, in other embodiments, the VGD 110 may be a variable vane diffuser, a variable wall diffuser, or other type of variable diffuser. The position of the VGD 110 within the diffuser passage 106 is adjustable in order to improve control and operation of the compressor 32. For example, the VGD 110 may be coupled to the actuator 112 (e.g., a two-stage actuator, an actuation system, etc.), which, upon instruction by the controller 114 (e.g., a control system), actuates or moves the VGD 110 from a previous position to a desired position. In some embodiments, the actuator 112 may be an electromechanical actuator, a magnetic actuator, a hydraulic actuator, or any other suitable type of actuator. As described herein, the flow control system 94 (e.g., the actuator 112 and/or the controller 114) is configured to operate in two or more stages or modes. For example, the actuator 112 may actuate the VGD 110 in a first stage or mode (e.g., high torque mode) by applying a first force to the VGD 110 and in a second stage or mode (e.g., low torque mode) by applying a second force to the VGD 110 that is less than the first force.
The controller 114 may control the position of the VGD 110 such that the VGD 110 adjusts a size of a flow path through the diffuser passage 106. For example, the controller 114 may control operation of the actuator 112 to increase or decrease a size of the flow path (e.g., refrigerant flow path 100) through the diffuser passage 106 without completely blocking the flow path through the diffuser passage 106 during operation of the compressor 32 (e.g., to control surge and/or capacity of the compressor 32). The controller 114 may also control operation of the actuator 112 to position the VGD 110 within the entire diffuser passage 106, such that the VGD 110 abuts the compressor discharge plate 116 (e.g., a diffuser plate) of the compressor 32, thereby completely blocking the diffuser passage 106 and preventing flow of refrigerant therethrough. In this manner, the VGD 110 is used as a flow check valve to mitigate or prevent spin and/or backspin (e.g., of the impeller 100), such as during non-operational periods or stoppage of the compressor 32.
The controller 114 may include processing circuitry 118 and a memory 120. The memory 120 may include a tangible, non-transitory, computer-readable medium that may store instructions that, when executed by the processing circuitry 118, may cause the processing circuitry 118 to perform various functions or operations described herein. To this end, the processing circuitry 118 may be any suitable type of computer processor or microprocessor capable of executing computer-executable code, including but not limited to one or more field programmable gate arrays (FPGA), application-specific integrated circuits (ASIC), programmable logic devices (PLD), programmable logic arrays (PLA), and the like. For example, the controller 114 may control an operating capacity of the compressor 32 based at least in part on certain operating and/or environmental conditions (e.g., refrigerant temperature). The controller 114 may also include data stored on the memory 120 indicating a desired position of the VGD 110 based on the operating capacity of the compressor 32. Further, the controller 114 may be configured to control a stage or actuating force of the actuator 112 based on a position of the VGD 110 within the diffuser passage 106 and/or based on an operational state of the compressor 32. For example, the controller 114 may control the actuator 112 to adjust a position of the VGD 110 using a first force or torque when the VGD 110 is within a first range of positions within the diffuser passage 106 and using a second force or torque, less than the first force or torque, when the VGD 110 is within a second range of positions within the diffuser passage 106. Control of the VGD 110 via the actuator 112 and the controller 114 is described in further detail below.
In the illustrated embodiment, the VGD 110 is shown in a home or “zero” position 138. For example, the home position 138 of the VGD 110 may be a threshold position (e.g., a lower threshold position) within the diffuser passage 106 beyond which the actuator 112 and/or controller 114 does not adjust the VGD 110 (e.g., further into the diffuser passage 106 and/or further towards the compressor discharge plate 116) during operational periods of the compressor 32. In other words, when the compressor 32 is operating, the actuator 112 and/or controller 114 is configured to move the VGD 110 within a first range of positions 140 in the diffuser passage 106 and does not position the VGD 110 beyond the home position 138 (e.g., closer to the compressor discharge plate 116). Thus, when the compressor 32 is operating, a gap 142 remains between a distal surface 144 of the VGD 110 and the compressor discharge plate 116, where a dimension (e.g., width) of the gap 142 from the distal surface 144 to the compressor discharge plate 116 is greater than or equal to the width 132 shown in
In accordance with present embodiments, the actuator 112 and/or controller 114 is also configured to selectively move the VGD 110 beyond the home position 138 and into contact with the compressor discharge plate 116. For example, during stoppage (e.g., non-operating periods, a fault sequence, and/or a shutdown sequence) of the compressor 32, the controller 114 may instruct the actuator 112 to move the VGD 110 beyond the home position 138 (e.g., further away from the nozzle base plate 109), such that the VGD 110 contacts the compressor discharge plate 116 to block (e.g., completely block) the discharge passage 106 and thereby block or prevent refrigerant flow through the discharge passage 106. In other words, during non-operational periods, a fault sequence, and/or a shutdown sequence of the compressor 32, the controller 114 may instruct the actuator 112 to move the VGD 110 within a second range of positions 146, such that the VGD 110 is positioned beyond the home position 128 (e.g., relative to the nozzle base plate 109). As illustrated in
As mentioned above, the flow control system 94 (e.g., the actuator 112) is configured to operate in two or more modes or stages. In a first mode or stage, the controller 114 may control the actuator 112 to adjust the position of the VGD 110 by applying a first force or torque (e.g., a large force and/or a force above a threshold amount) to the VGD 110, and in the second mode or stage the controller 114 may control the actuator 112 to adjust the position of the VGD 110 by applying a second force or torque (e.g., a small force and/or a force below a threshold amount) to the VGD 110 that is less than the first force or torque. For example, the controller 114 may be configured to instruct the actuator 112 to operate in the first mode or stage when the VGD 110 is within the first range of positions 140 and to instruct the actuator 112 to operate in the second mode or stage when the VGD 110 is within the second range of positions 146. By utilizing the first or large force to move the VGD 110 across the first range of positions 140 when the compressor 32 is operating, a position of the VGD 110 may be quickly and effectively adjusted during operation of the compressor 32 to control surge and/or capacity. By utilizing the second or small force to move the VGD 110 across the second range of positions 146 when the compressor 32 is not operating, the VGD 110 may be positioned to contact the compressor discharge plate 116, and therefore block natural refrigerant migration through the diffuser passage 106, while avoiding transfer of undesirable forces to the VGD 110, the linkage 136, the actuator 112, or other components of the compressor 32.
As an example, the compressor 32 may operate with the VGD 110 positioned in the diffuser passage 106 within the first range of positions 140, and the controller 114 may receive an indication (e.g., feedback) of a fault or shutdown of the compressor 32 (e.g., from the control board 40). To this end, the controller 114 may be communicatively coupled to other control components of the vapor compression system 14 and/or HVAC&R system 10 that regulate system operations. Based on the indication, the controller 114 may instruct the actuator 112 to adjust the position of the VGD 110 to the home position 138 in the first mode or stage of the actuator 112 (e.g., using the first or large force). Once the VGD 110 reaches the home position 138, the controller 114 may instruct the actuator 112 to adjust the position of the VGD 110 from the home position 138 to a position in contact with the compressor discharge plate 116 in the second mode or stage of the actuator 112 (e.g., using the second or small force). As discussed further below, once the VGD 110 is in sufficient contact with the compressor discharge plate 116, the controller 116 may instruct the actuator 112 to maintain the position of the VGD 110 against the compressor discharge plate 116 to block or prevent refrigerant flow through the discharge passage 106. For example, the actuator 112 may maintain the position of the VGD 110 in contact with the compressor discharge plate 116 until a command to operate the compressor 32 or to unblock the diffuser passage 106 is received by the controller 114 (e.g., from the control board 40).
When the controller 114 determines that the VGD 110 is positioned in sufficient contact with the compressor discharge plate 116 (e.g., based on feedback from the sensor 150), the controller 114 may instruct the actuator 112 to activate the locking system 152 to maintain the position of the VGD 110 within the diffuser passage 106 and may discontinue operation of the actuator 112 to move the VGD 110. In some embodiments, the locking system 152 may include a mechanical locking system configured to maintain a position of the actuator 112 and the VGD 110. The mechanical locking system may include, for example, a mechanical interlocking device, a key, a pin, a tapered ring, a spring lock, a brake mechanism, a piston, another suitable locking device, or any combination thereof. In some embodiments, the locking system 152 may include an electric locking system configured to block electrical power supplied to the actuator 112 and thereby retain a position of the actuator 112 and the VGD 110. Other embodiments of the locking system 152 may include additional or alternative components, such as a pneumatic lock, a hydraulic lock, a magnetic lock, an electromechanical lock, or any combination thereof.
It should be appreciated that embodiments in accordance with the present techniques may utilize additional and/or alternative sensors 150 configured to provide feedback to the controller 114. For example, the flow control system 94 may include sensors 150, such as position sensors, current sensors, temperature sensors, pressure sensors, flow rate sensors, contact sensors or other sensors to enable the functionality described above. In some embodiments, one or more sensors 150 may be coupled to other components of the vapor compression system 14 and/or disposed in other locations along or within refrigerant circuit 80.
As discussed above, embodiments of the present disclosure are directed to systems and methods for utilizing a variable geometry diffuser (VGD) as a flow check valve in a compressor to substantially reduce, block, or prevent undesirable refrigerant flow across the compressor and thereby mitigate spin and/or backspin of the compressor. Embodiments include an actuator configured to operate in multiple modes to actuate and move the VGD within a diffuser passage of the compressor, and the mode of operation may be based on an operational state of the compressor and/or based on a position of the VGD within the diffuser passage. The actuator may operate in a first mode when the compressor is operating in order to move the VGD within the diffuser passage and adjust a size of a flow path through the diffuser passage, such as for surge or capacity control of the compressor. The control system may operate the actuator in a second mode when the compressor is not operating in order to move the VGD within the diffuser passage and abut an opposing surface of the diffuser passage, thereby substantially completely blocking or closing the flow path through the diffuser passage. Thus, the disclosed systems and methods enable the use of the VGD to block or prevent refrigerant flow through the compressor so as to reduce spin and/or backspin of the compressor when the compressor is not operating.
While only certain features and embodiments of the disclosure have been illustrated and described, many modifications and changes may occur to those skilled in the art, such as variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, including temperatures and pressures, mounting arrangements, use of materials, colors, orientations, and so forth without materially 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 varied or re-sequenced according to alternative embodiments. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the disclosure. Furthermore, in an effort to provide a concise description of the exemplary embodiments, all features of an actual implementation may not have been described, such as those unrelated to the presently contemplated best mode of carrying out the disclosure, or those unrelated to enabling the claimed disclosure. It should be noted that in the development of any such actual implementation, as in any engineering or design project, numerous implementation specific decisions may be made. Such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure, without undue experimentation.
The techniques presented and claimed herein are referenced and applied to material objects and concrete examples of a practical nature that demonstrably improve the present technical field and, as such, are not abstract, intangible or purely theoretical. Further, if any claims appended to the end of this specification contain one or more elements designated as “means for [perform]ing [a function]... ” or “step for [perform]ing [a function]... ”, it is intended that such elements are to be interpreted under 35 U.S.C. 112(f). However, for any claims containing elements designated in any other manner, it is intended that such elements are not to be interpreted under 35 U.S.C. 112(f).
This application claims priority from and the benefit of U.S. Provisional Application Serial No. 62/982,573, entitled “SYSTEM AND METHOD FOR OPERATION OF VARIABLE GEOMETRY DIFFUSER AS CHECK VALVE,” filed Feb. 27, 2020, which is hereby incorporated by reference in its entirety for all purposes.
Filing Document | Filing Date | Country | Kind |
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PCT/US2021/020049 | 2/26/2021 | WO |
Number | Date | Country | |
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62982573 | Feb 2020 | US |