Slide valve system for compressor

Abstract

A slide valve system (50) for a screw compressor (14) includes a slide body (68) configured to be disposed within a slide bore (110) of a housing (52) of the screw compressor (14), where the slide body (68) is configured to translate within the slide bore (110) along a first axis (62) and along a compression chamber (58) of the screw compressor (14). The slide valve system (50) also includes a cavity (104) formed within the slide body (68) and a valve body (102) disposed within the cavity (104). The valve body (102) is adjustable within the cavity (104) between an activated position and a deactivated position, and the valve body (102) is configured to translate along a second axis, cross-wise to the first axis (62), within the cavity (104).

Description

New International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd SLIDE VALVE SYSTEM FOR COMPRESSORCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority from and the benefit of U.S. Provisional Application No. 63 / 719,347, entitled “SLIDE VALVE SYSTEM FOR COMPRESSOR,” filed November 12, 2024, which is herein incorporated by reference in its entirety for all purposes.BACKGROUND

[0002] 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.

[0003] Heating, ventilation, air conditioning, and refrigeration (HVAC&R) systems, or vapor compression systems, are utilized in residential, commercial, and industrial environments to control environmental properties, such as temperature and humidity, of a conditioned space. In general, HVAC&R systems circulate a working fluid (e.g., refrigerant), which changes phases between vapor, liquid, and combinations thereof in response to exposure to different temperatures and pressures associated with operation of the HVAC&R system. For example, an HVAC&R system may utilize a compressor to circulate the working fluid to a heat exchanger (e.g., evaporator, condenser) which may transfer heat between the working fluid and another fluid (e.g., cooling fluid) flowing through or across the heat exchanger. One type of compressor that may be utilized in an HVAC&R system is a screw compressor, which generally includes one or more cylindrical rotors mounted inside a hollow casing. Twin screw compressor rotors typically have outer surfaces with helically extending lobes and grooves that form threads extending about respective circumferences of the rotors. During operation, the threads of the rotors mesh together, with the lobes of one rotor meshing with the corresponding grooves of the other rotor to form a series of spaced compression cavities (e.g., spaced gaps) between the rotors. The spaced compression cavities cooperatively form a compression chamber that is in fluid communication with a compressor inlet or port and continuously reduces a volume of the fluid as the rotors rotate to compress the fluid directed through the compression chamber.

[0004] In some instances, it is desirable to adjust an operating capacity and / or a volume ratio of a compressor. Some screw compressors may include a slide valve system, such as a tandemNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd slide valve system, that may be operated to adjust the operating capacity and / or volume ratio of the screw compressor. Unfortunately, existing systems configured to adjust the operating capacity and / or volume ratio of a screw compressor are mechanically complex with numerous interconnected components and are acutely sensitive to various operating conditions or adjustments, which results in substantial costs associated with manufacturing, assembly, and service of the screw compressor.SUMMARY

[0005] 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 certain embodiments and that these aspects are not intended to limit the scope of this disclosure. Indeed, this disclosure may encompass a variety of aspects that may not be set forth below. Embodiments according to the invention are disclosed in particular in the appended claims.

[0006] In one embodiment of the present disclosure, a slide valve system for a screw compressor includes a slide body configured to be disposed within a slide bore of a housing of the screw compressor, where the slide body is configured to translate within the slide bore along a first axis and along a compression chamber of the screw compressor. The slide valve system also includes a cavity formed within the slide body and a valve body disposed within the cavity. The valve body is adjustable within the cavity between an activated position and a deactivated position, and the valve body is configured to translate along a second axis, cross-wise to the first axis, within the cavity.

[0007] In another embodiment, a screw compressor includes a housing and a slide valve system. The housing includes a compression chamber configured to accommodate a screw rotor therein and includes a slide bore. The slide valve system includes a slide body disposed within the slide bore and configured to translate within the slide bore along a first axis, where the slide body includes a first rotor mating surface configured to at least partially define the compression chamber, and the slide body includes a cavity formed therein. The slide valve system also includes a valve body disposed within the cavity, where the valve body includes a second rotor mating surface configured to at least partially define the compression chamber, and the valve body is configured to translate within the cavity along a second axis, cross-wise to the first axis, between an activated position and a deactivated position. The first rotor mating surface and the second rotor mating surface are aligned with one another along the first axis in the activated position ofNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd the valve body, and the second rotor mating surface is offset from the first rotor mating surface along the second axis in the deactivated position of the valve body.

[0008] In a further embodiment, a screw compressor includes a housing having a suction side, a discharge side, compression chamber, and a slide bore, a screw rotor disposed within the compression chamber and configured to drive a working fluid through the compression chamber from the suction side to the discharge side, and a slide valve system. The slide valve system includes a slide body disposed within the slide bore and configured to translate within the slide bore along a first axis, where the slide body includes a first rotor mating surface configured to at least partially define the compression chamber, and the slide body includes a cavity formed therein. The slide valve system also includes a valve body disposed within the cavity, where the valve body has a second rotor mating surface, and the valve body is configured to translate within the cavity along a second axis, cross-wise to the first axis, between an activated position and a deactivated position. The slide valve system further includes a chamber disposed within the cavity between the valve body and the slide body. The chamber is configured to receive a flow of lubricant to transition the valve body from the deactivated position to the activated position, the valve body includes a lubricant flow path formed therethrough, and the lubricant flow path is configured to direct a portion of the flow of lubricant from the chamber to the compression chamber, the suction side of the screw compressor, or both, in the activated position of the valve body. The second rotor mating surface at least partially defines the compression chamber in the activated position of the valve body, and the second rotor mating surface at least partially defines a bypass flow path from the compression chamber to the suction side of the screw compressor in the deactivated position of the valve body.New International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Various aspects of this disclosure may be better understood upon reading the following detailed description and upon reference to the drawings in which:

[0010] FIG. l is a schematic of an embodiment of a vapor compression system, in accordance with an aspect of the present disclosure;

[0011] FIG. 2 is a perspective cross-sectional view of an embodiment of a compressor having a slide valve system, in accordance with an aspect of the present disclosure;

[0012] FIG. 3 is a perspective view of a portion of an embodiment of a slide valve system of a compressor, in accordance with an aspect of the present disclosure;

[0013] FIG. 4 is a cross-sectional side view of a portion of an embodiment of a compressor having a slide valve system, in accordance with an aspect of the present disclosure;

[0014] FIG. 5 is a perspective view of a portion of an embodiment of slide valve system of a compressor, in accordance with an aspect of the present disclosure;

[0015] FIG. 6 is a perspective cross-sectional view of a portion of an embodiment of a compressor having a slide valve system, in accordance with an aspect of the present disclosure;

[0016] FIG. 7 is a perspective cross-sectional view of a portion of an embodiment of a compressor having a slide valve system, in accordance with an aspect of the present disclosure;

[0017] FIG. 8 is a perspective cross-sectional view of a portion of an embodiment of a slide valve system of a compressor, in accordance with an aspect of the present disclosure;

[0018] FIG. 9 is a perspective cross-sectional view of an embodiment of a compressor having a slide valve system, in accordance with an aspect of the present disclosure;

[0019] FIG. 10 is a perspective cross-sectional view of a portion of an embodiment of a compressor having a slide valve system, in accordance with an aspect of the present disclosure;

[0020] FIG. 11 is a perspective cross-sectional view of a portion of an embodiment of a compressor having a slide valve system, in accordance with an aspect of the present disclosure; and

[0021] FIG. 12 is an axial cross-sectional view of a portion of an embodiment of a compressor having a slide valve system, in accordance with an aspect of the present disclosure.DETAILED DESCRIPTION

[0022] 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 actualNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd 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 may 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.

[0023] 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.

[0024] As used herein, the terms “approximately,” “generally,” “substantially,” and so forth, are intended to convey that the property value being described may be within a relatively small range of the property value, as those of ordinary skill would understand. For example, when a property value is described as being “approximately” equal to (or, for example, “substantially similar” to) a given value, this is intended to convey that the property value may be within + / - 5%, within + / - 4%, within + / - 3%, within + / - 2%, within + / - 1%, or even closer, of the given value. Similarly, when a given feature is described as being “substantially parallel” to another feature, “generally perpendicular” to another feature, and so forth, this is intended to convey that the given feature is within + / - 5%, within + / - 4%, within + / - 3%, within + / - 2%, within + / - 1%, or even closer, to having the described nature, such as being parallel to another feature, being perpendicular to another feature, and so forth. Mathematical terms, such as “parallel” and “perpendicular,” should not be rigidly interpreted in a strict mathematical sense, but should instead be interpreted as one of ordinary skill in the art would interpret such terms. For example, one of ordinary skill in the art would understand that two lines that are substantially parallel to each other are parallel to a substantial degree, but may have minor deviation from exactly parallel.

[0025] As briefly discussed above, a heating, ventilation, air conditioning, and refrigeration (HVAC&R) system may be configured to operate to satisfy heating and / or cooling demands within a building, home, commercial appliance, industrial system, or other conditioned space. ForNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd example, the HVAC&R system may include a vapor compression system (e.g., chiller system, heat pump system) that transfers thermal energy between a working fluid (e.g., refrigerant, ammonia) and a fluid to be conditioned (e.g., air, water, brine). The vapor compression system may include one or more vapor compression circuits (e.g., heat pumps, working fluid circuits) that each include a condenser and an evaporator that are fluidly coupled to one another via one or more conduits (e.g., vapor compression circuit, working fluid circuit, refrigeration circuit). Further, each vapor compression circuit may include a compressor configured to pressurize and circulate the working fluid through the vapor compression circuit and, thus, enable the transfer of thermal energy between the working fluid and the fluid to be conditioned via the condenser and / or the evaporator. For example, the compressor may direct the working fluid to a condenser, which may cool and condense the working fluid. The condensed working fluid may be directed toward an expansion device, which may reduce a pressure of the working fluid. From the expansion device, the cooled working fluid may be directed to an evaporator, where the working fluid may be placed in a heat exchange relationship with a conditioning fluid to cool the conditioning fluid. The compressor may then receive the working fluid from the evaporator for pressurization to restart the vapor compression cycle.

[0026] During operation of the vapor compression system, parameters of the working fluid at various positions or locations along the working fluid circuit and / or a load demand on the vapor compression system may fluctuate. Accordingly, operation of the compressor may be adjusted to enable operation of the vapor compression system and / or the compressor at target or desired levels (e.g., operating conditions). For example, a volume ratio (e.g., a ratio between a suction volume and a discharge volume of working fluid) of the compressor may be adjusted. In some embodiments, a speed of one or more rotors of the compressor may be adjusted via a motor or another suitable drive to cause an adjustment of an operating capacity of the compressor. However, certain compressors may be configured to operate at a fixed speed, which may limit operating capacity adjustments. Some compressors may be configured to operate at variable speeds, but variable speed operation of such compressors may nevertheless be inadequate to effectively adjust the operating capacity in a desired manner. Unfortunately, existing systems that adjust operating capacities and / or volume ratios of compressors are susceptible to various drawbacks. For example, existing volume ratio control systems are typically complex, expensive, unreliable, and / or difficult to operate.New International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd

[0027] Accordingly, embodiments of the present disclosure are directed toward a slide valve system for a compressor, such as a screw compressor, that enables improved control and / or adjustment of a volume ratio of the compressor. The techniques described herein may also enable improved control and / or adjustment of an operating capacity of the compressor, in some embodiments. As described in further detail below, the slide valve system includes a slide body (e.g., single slide body, single beam) having a valve configured to enable more accurate and robust adjustment of the volume ratio and / or operating capacity of the compressor. The slide body may also be incorporated with the screw compressor in a more balanced manner that enables more rapid, responsive, reliable, and repeatable adjustment of a position of the slide body within the compressor to cause a desired adjustment to the volume ratio. Moreover, the present embodiments may be implemented with reduced complexity, increased accessibility, and reduced costs compared to existing volume ratio control systems. The techniques described herein also provide additional advantages over existing systems, as discussed below.

[0028] Turning now to the drawings, FIG. 1 is a schematic of an embodiment of a heating, ventilation, air conditioning, and refrigeration (HVAC&R) system 10 having a vapor compression circuit 12. For example, the HVAC&R system 10 may include a chiller system and / or a heat pump system. The vapor compression circuit 12 (e.g., working fluid circuit) may circulate a working fluid (e.g., heat transfer fluid, refrigerant) to provide heating, cooling, and / or other condition to a load. As shown, the vapor compression circuit 12 includes a compressor 14 (e.g., screw compressor), a condenser 16 (e.g., first heat exchanger), a first expansion valve 18, an economizer 20, a second expansion valve 22, and an evaporator 24 (e.g., second heat exchanger). The HVAC&R system 10 may also include a motor 26 configured to drive the compressor 14. In some embodiments, the motor 26 may be powered by a variable speed drive (VSD) 28 that receives alternating (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 26 to enable variable speed operation of the compressor 14. In other embodiments, the motor 26 may be configured to operate the compressor 14 at a fixed speed (e.g., single speed) and / or may be powered directly from an AC or direct current (DC) power source. The motor 26 may include any type of motor, such as a switched reluctance motor, an induction motor, an electronically commutated motor, a permanent magnet motor, an engine (e.g., non-electrical engine, combustion engine), a gas turbine, or any combination thereof. In certain embodiments, the HVAC&R system 10 may include a controller 30 (e.g., control system, control panel) configured to control operationNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd of the HVAC&R system 10. For example, the controller 30 may be communicatively coupled to the VSD 28 and may be configured to control operation of the VSD 28, and thus, the compressor 14. As will be appreciated, the controller 30 may include processing circuitry and a memory (e.g., non-transitory, computer-readable medium) configured to store executable instructions that may be executed by the processing circuitry to control operation of the HVAC&R system 10.

[0029] The compressor 14 is configured to compress a working fluid vapor and deliver the vapor to the condenser 16 via a discharge outlet of the compressor 14. As mentioned above, the compressor 14 may be a screw compressor. The condenser 16 may place the working fluid in a heat exchange relationship with a cooling fluid to enable transfer of heat from the working fluid to the cooling fluid (e.g., water or air). Accordingly, the working fluid vapor may condense to a working fluid liquid in the condenser 16. The working fluid liquid may be directed from the condenser 16 through the first expansion valve 18 positioned upstream of the economizer 20 (e.g., flash tank, intercooler) along the vapor compression circuit 12. The first expansion valve 18 is configured to reduce a pressure of (e.g., expand) the liquid working fluid received from the condenser 16. During the expansion process, a portion of the liquid may vaporize, and the economizer 20 may therefore be used to separate the working fluid received from the first expansion valve 18 into vapor working fluid and liquid working fluid.

[0030] Additionally, the economizer 20 may enable further expansion of the liquid working fluid due to a pressure drop experienced by the liquid working fluid upon entering the economizer 20 (e.g., due to a rapid increase in volume experienced upon entering the economizer 20). The vapor working fluid in the economizer 20 may be drawn (e.g., by the compressor 14) through an economizer conduit 32 (e.g., suction line, economizer line, economizer conduit) to the compressor 14. In some embodiments, the vapor working fluid in the economizer 20 may be drawn to an intermediate stage of the compressor 14. The liquid working fluid that collects in the economizer 20 may be at a lower enthalpy than the liquid working fluid exiting the condenser 16 due to expansion via the first expansion valve 18 and / or in the economizer 20. The liquid working fluid from the economizer 20 may then flow through the second expansion valve 22 and thereafter to the evaporator 24.

[0031] The liquid working fluid delivered to the evaporator 24 may absorb heat from another fluid, such as a conditioning fluid, which may or may not be the same fluid as the cooling fluid directed through the condenser 16. The liquid working fluid in the evaporator 24 may undergo a phase change from liquid working fluid to working fluid vapor. For example, the evaporator 24New International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd may reduce the temperature of the conditioning fluid via thermal heat transfer with the working fluid directed through the evaporator 24. Thus, liquid working fluid directed to the evaporator 24 may absorb heat from the conditioning fluid, which may cause the liquid working fluid to evaporate to become vapor working fluid. Thereafter, the vapor working fluid may be directed from the evaporator 24 to the compressor 14 to complete and restart the vapor compression cycle.

[0032] As mentioned above, some screw compressors may include features to adjust an operating capacity and / or a volume ratio of the screw compressor, but existing systems are mechanically complex, unreliable, expensive, and / or difficult to operate. For example, existing systems typically include a large number of interconnected components and are generally sensitive to variations in adjustments, operating conditions, and so forth. Indeed, conventional systems that adjust a volume ratio of a screw compressor may be difficult to operate and unreliable, yet remain expensive to manufacture, assembly, maintain, and operate. Accordingly, present embodiments are directed to an improved slide valve system for a screw compressor that enhances control and / or adjustment of a volume ratio and / or an operating capacity of the screw compressor. Further, embodiments described herein enable improved volume ratio control and / or operating capacity control with fewer components and reduced complexity.

[0033] With the foregoing in mind, FIG. 2 is a perspective cross-sectional view of an embodiment of the compressor 14 (e.g., screw compressor) that includes a slide valve system 50 (e.g., single beam slide valve, slide valve assembly) configured to enable improved control and adjustment of a volume ratio and / or an operating capacity of the compressor 14. The compressor 14 includes a housing 52, a suction side 54 (e.g., inlet end, suction end, intake portion), a discharge side 56 (e.g., outlet end, discharge side, discharge portion), a compression chamber 58 formed within the housing 52, and at least one rotor 60 (e.g., screw rotor, screw) disposed within the compression chamber 58. In some embodiments, the compressor 14 includes two rotors 60 (e.g., screw rotors) disposed within the compression chamber 58. For example, the compressor 14 may include a male rotor and a female rotor having respective lobes (e.g., threads) and grooves (e.g., flutes) extending about respective circumferences of the rotors 60 and configured to mesh with one another. The lobes and grooves may form a series of gaps between the rotors 60. The gaps form cyclical compression cavities that extend along the compression chamber 58. The gaps may be fluidly coupled with a suction port (e.g., compressor inlet, suction side 54) of the compressor 14 at one end of the housing 52 and may continuously reduce in volume as the rotors 60 rotate to compress a working fluid (e.g., refrigerant) and direct the working fluid toward a discharge portNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd (e.g., compressor outlet, discharge side 56) at an opposite end of the housing 52. The compressor 14 may be configured to rotate the rotors 60 at a fixed speed (e.g., a single speed) or may be configured to rotate the rotors 60 at multiple speeds (e.g., variable speeds).

[0034] To facilitate the following discussion, the compressor 14 and the components thereof may be described with reference to a longitudinal axis 62 (e.g., axial direction, first axis), a vertical axis 64 (e.g., orthogonal axis, radial axis, second axis), and a lateral axis 66 (e.g., third axis). It should be noted that the vertical axis 64 and the lateral axis 66 extend in radial directions relative to the longitudinal axis 62. Respective rotational axes of the one or more rotors 60 of the compressor 14 may also extend along the longitudinal axis 62. Further, it should be appreciated that the longitudinal axis 62, the vertical axis 64, and the lateral axis 66 are illustrated for ease of reference and are not intended to limit the present disclosure to the orientations described herein. For example, in some implementations, the vertical axis 64 may be oriented in any suitable direction and may not be oriented in a direction of gravity. Similarly, the longitudinal axis 62 and the lateral axis 66 may not be oriented in a purely horizontal direction (e.g., relative to gravity), in some implementations.

[0035] As mentioned above, the compressor 14 also includes the slide valve system 50. The slide valve system 50 is configured to enable adjustment of a volume ratio of the compressor 14 and / or adjustment of an operating capacity of the compressor 14. In accordance with the present techniques, the slide valve system 50 includes a slide body 68 (e.g., single beam body, single beam) configured to translate within the housing 52 (e.g., within a slide bore 110 of the housing 52) along the longitudinal axis 62 and along the compression chamber 58 of the compressor 14. The slide body 68 defines a radial discharge port 70 configured to enable discharge of working fluid from the compression chamber 58 (e.g., in addition to an axial discharge port of the housing 52). A position of the slide body 68 along the longitudinal axis 62 (e.g., within the housing 52) may be adjusted to modify a position of the radial discharge port 70 (e.g., relative to the rotors 60). Translation of the slide body 68, and therefore the radial discharge port 70, also adjusts an effective working length of the rotors 60, which causes a corresponding change in the volume ratio of the compressor 14. Specifically, as the position of the radial discharge port 70 (e.g., relative to the rotors 60) is adjusted, a volume of the working fluid discharged from the compression chamber 58 (e.g., discharge volume) is adjusted. Indeed, the discharge volume of the working fluid may be adjusted relative to a volume of the working fluid received within and / or by the compressionNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd chamber 58 (e.g., suction volume, swept volume), thereby causing an adjustment to the volume ratio of the compressor 14.

[0036] In accordance with the present techniques, the slide valve system 50 is configured to provide more robust, accurate, and reliable adjustment of the slide body 68. For example, the slide body 68 may include a single beam instead of multiple beams configured to translate (e.g., independently of one another) along the longitudinal axis 62. The single beam of the slide body 68 may be supported at multiple axial locations along the slide body 68 (e.g., opposing ends of the compression chamber 58) to provide additional structural support of the slide body 68. For example, the slide body 68 may be supported at multiple axial locations (e.g., along the longitudinal axis 62) via support rings 69 (e.g., supports, retention rings, annular supports, bearing supports, beam supports) disposed within and coupled to the housing 52 of the compressor 14. As shown, the support rings 69 may be disposed at ends (e.g., opposite ends, along the longitudinal axis 62) of the compression chamber 58. Therefore, the support rings 69 may support the slide body 68 (e.g., single beam) at multiple axial positions and / or locations (e.g., along the longitudinal axis 62) along the slide body 68. In some embodiments, the support rings 69 may contact and / or abut the slide body 68 to support the slide body 68 (e.g., at offset axial positions of the slide body 68 along the longitudinal axis 62) at each position of a plurality of positions of the slide body 68 along the longitudinal axis 62 and within the housing 52 (e.g., slide bore). Indeed, the support rings 69 may continually and / or simultaneously contact and / or support the slide body 68 during translation of the slide body 68 within the housing 52, as well as during instances in which the slide body 68 is stationary. In this way, the slide valve system 50 (e.g., slide body 68) may be more robustly supported within the housing 52 and may translate within the housing 52 in a more reliable, predictable, and effective manner.

[0037] Additionally, the slide valve system 50 may be configured to utilize a suction pressure and a discharge pressure of the compressor 14 to provide improved balance to the slide valve system 50 (e.g., reduced and / or zero net axial force along the longitudinal axis 62). For example, the slide valve system 50 includes a piston assembly 72 having a cylinder 74 and a piston 76 disposed within the cylinder 74. One or more components of the piston assembly 72 may be coupled to the slide body 68, as described in further detail below. The piston 76 separates an internal volume of the cylinder 74 into a first chamber 78 (e.g., first volume) and a second chamber 80 (e.g., second volume). The second chamber 80 may be exposed to a suction pressure of the compressor 14, while the first chamber 78 may be exposed to a discharge pressure of theNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd compressor 14. As shown in the illustrated embodiment, the first chamber 78 is formed at least partially by a first face 106 (e.g., first side, first surface) of the piston 76, and the second chamber 80 is formed at least partially by a second face 108 (e.g., second side, second surface) of the piston 76, opposite the first face 106. The first face 106 of the piston 76 and the first chamber 78 are positioned opposite the housing 52 and the slide body 68 relative to the second chamber 80 and the second face 108 of the piston 76. In other words, the second chamber 80 is disposed between the first chamber 78 and the housing 52 along the longitudinal axis 62.

[0038] To expose the first chamber 78 to the discharge pressure of the compressor 14, in some embodiments, the slide valve system 50 may include one or more ports 82 (e.g., one or more balancing ports, one or more discharge pressure ports, one or more slide body ports) extending from the discharge side 56 (e.g., radial discharge port 70) to the first chamber 78. The ports 82 may include one or more channels or passages formed in (e.g., through) a discharge pressure face 112 of the slide body 68 and extending through the slide body 68 (e.g., along the longitudinal axis 62). As discussed further below, one or more conduits may extend from the ports 82 and through the second chamber 80 to fluidly couple to the first chamber 78. Thus, a discharge pressure of the compressor 14 may be present in the first chamber 78 and may act on the slide body 68 and the piston 76, as indicated by arrows 84. A suction pressure of the compressor 14 may be present in the second chamber 80 and may act on the piston 76 and the slide body 68, as indicated by arrows 86. To this end, the cylinder 74 may be coupled (e.g., mounted, attached) to the housing 52, and a suction pressure passage 114 may fluidly couple the suction side 54 (e.g., suction chamber) of the housing 52 and the second chamber 80. Thus, the second chamber 80 may be exposed to a suction pressure of the compressor 14.

[0039] To enable balancing of the forces acting on the slide body 68 and the piston 76, respective geometries, sizes, and / or dimensions (e.g., cross-sectional geometries, surface geometries, measurements) of the slide body 68, the piston 76, and / or other components of the slide valve system 50 and / or the compressor 14 may be determined, selected, and / or utilized to enable balancing of the forces (e.g., axial forces, discharge and suction pressures) acting on the slide body 68 and the piston 76. Indeed, the geometries of the slide body 68 and the piston 76, such as respective geometries and / or sizes of the first face 106 of the piston 76, the second face 108 of the piston 76, the discharge pressure face 112 of the slide body 68, the suction pressure passage 114, the ports 82, the conduits, another component or feature, or any combination thereof, may be configured to enable inherent balancing of the forces (e.g., axial forces, discharge andNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd suction pressures) acting on the slide body 68 and the piston 76 in some or all working conditions of the compressor 14.

[0040] To further enable more robust, reliable, and accurate control of the slide body 68 (e.g., positioning of the slide body 68), the slide valve system 50 includes an actuation system 88 (e.g., linear actuation system) configured to adjust and position the slide body 68 along the longitudinal axis 62 (e.g., within the housing 52, relative to the rotors 60) in a desired manner. The actuation system 88 described herein may, in some embodiments, be more effectively utilized at least partially due to the axial force balancing of the slide valve system 50 described above. The actuation system 88 may include a motor 90 (e.g., stepper motor) configured to drive translation of a shaft 92 attached to the slide body 68. For example, the actuation system 88 may include a ball screw spindle assembly 94 having a screw shaft 96 (e.g., threaded shaft, screw spindle, ball screw spindle, threaded rod) and a nut 98 (e.g., ball nut, ball screw) disposed about the screw shaft 96 and secured to the shaft 92 and the piston 76. As shown, the screw shaft 96 and the nut 98 are disposed within the cylinder 74. The nut 98 is configured to convert rotary movement of the screw shaft 96 into linear movement, such as linear movement of the piston 76, the shaft 92, and / or the slide body 68. It should be noted that the piston 76 and the shaft 92 may be axially fixed to one another (e.g., relative to the longitudinal axis 62, via the nut 98), such that forces acting on the piston 76 (e.g., axial forces) may be transferred to the slide body 68 via the shaft 92 to enable the axial force balancing functionalities described herein. The actuation system 88 may also include a bearing support 100 configured to support an end of the screw shaft 96 adjacent the motor 90. The motor 90 may be configured to induce rotational motion of the screw shaft 96. In some embodiments, the motor 90 may be operatively coupled to the screw shaft 96 via one or more gears, one or more magnetic couplings, or both.

[0041] As the screw shaft 96 is driven into rotation, rotary movement of the screw shaft 96 may be converted into linear movement via the nut 98, and the nut 98 may translate along the screw shaft 96 and along the longitudinal axis 62. Therefore, the piston 76 and the shaft 92 secured to the nut 98 may also translate along the longitudinal axis 62. In this way, adjustment of the slide body 68 along the longitudinal axis 62 is enabled. As mentioned above, the motor 90 may be a stepper motor, which may enable more rapid, responsive, reliable, and repetitive actuation and adjustment of the slide body 68 within the housing 52. Moreover, the actuation system 88 described herein may enable adjustment of the slide body 68 utilizing feed-forward techniques and / or control schemes. In other words, a position of the slide body 68 may be determined basedNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd on operation of the actuation system 88 (e.g., control signals provided to the motor 90). Indeed, in some embodiments, the position of the slide body 68 may be determined without reliance on subsequently received feedback indicative of the position of the slide body 68. For example, present embodiments may not include position indicators (e.g., slide body 68 position indicators, Vi-position indicators), sensors, transmitters, and / or other components that may be susceptible to operational interruptions and / or irregularities. Indeed, the present techniques may be incorporated to enable faster, more reliable, repeatable, and / or more accurate positioning and adjustment of the slide body 68 without conventional sensors or indicators traditionally utilized to determine a position (e.g., feedback) of a slide valve within a screw compressor.

[0042] Additionally, present embodiments of the slide valve system 50 also include a valve 102 (e.g., plug valve, valve body, plug let-out valve [PLOV], lubricant valve, oil valve) incorporated with the slide body 68. The valve 102 (e.g., valve body) may be disposed within a cavity 104 (e.g., pocket, recess, valve cavity) formed in the slide body 68, and the valve 102 is configured to translate within the cavity 104. Specifically, the valve 102 is configured to translate within the cavity 104 along an axis cross-wise to the longitudinal axis 62 along which the slide body 68 may be translated. For example, the valve 102 may translate within the cavity 104 and relative to the slide body 68 along the vertical axis 64 (e.g., second axis cross-wise to first axis, radially relative to the longitudinal axis 62). The valve 102 is configured to further enable improved operation of the compressor 14. For example, the valve 102 (e.g., valve body) may be actuated to enable improved unloading of the compressor 14, capacity control of the compressor 14, and / or supply of lubricant (e.g., oil) to the compressor 14. Additional details of the valve 102 and operation of the slide valve system 50 are described further below.

[0043] FIG. 3 is a perspective view of a portion of an embodiment of the slide valve system 50, in accordance with aspects of the present disclosure. As described above, the slide valve system 50 includes the slide body 68 (e.g., single beam body) configured to translate within the housing 52 (e.g., slide bore) of the compressor 14 (e.g., screw compressor). The illustrated embodiment of the slide valve system 50 also includes certain components of the piston assembly 72 (e.g., piston 76) and the actuation system 88 (e.g., shaft 92, nut 98). Additionally, the slide valve system 50 (e.g., piston assembly 72) includes conduits 118 coupled to the slide body 68. Each conduit 118 may be fluidly coupled to a respective channel or passage (e.g., port 82) formed in the slide body 68 to enable fluid coupling of the discharge side 56 of the compressor 14 and the first chamber 78 of the cylinder 74, as described above. For example, each conduit 118 may extendNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd from the slide body 68, through the second chamber 80, and to the piston 76 and may fluidly couple one of the ports 82 formed in the slide body 68 with a corresponding port 119 (e.g., piston port) formed in (e.g., through) the piston 76. Indeed, the conduits 118 may be mechanically coupled to the slide body 68 and the piston 76, in some embodiments. In this way, the discharge side 56 of the compressor 14 may be fluidly coupled with the first chamber 78 of the cylinder 74 via the ports 82, the conduits 118, and the ports 119 to enable application of a discharge pressure within the first chamber 78 of the cylinder 74.

[0044] The slide body 68 further includes rotor mating surfaces 120 (e.g., discharge pressure surfaces, arcuate surfaces, curved surfaces, first rotor mating surfaces). Each rotor mating surface 120 is configured to mate and / or engage with one of the rotors 60 of the screw compressor 14. The rotor mating surfaces 120 may also function as extensions of surfaces of the housing 52 of the compressor 14. Indeed, the rotor mating surfaces 120 may at least partially define the compression chamber 58 of the compressor 14. As the position of the slide body 68 is adjusted along the longitudinal axis 62, the position of the radial discharge port 70 is adjusted and an amount or portion of the rotor mating surfaces 120 that engages with (e.g., overlaps with) the rotors 60 is adjusted to modify an effective working length of the rotors 60 (e.g., an effective size of the compression chamber 58). As the position of the radial discharge port 70 and the effective working length of the rotors 60 are adjusted, the compression volume ratio of the compressor 14 is also adjusted.

[0045] As mentioned above, the slide body 68 also includes the cavity 104 formed therein. The cavity 104 may be formed in the rotor mating surfaces 120 and may extend into the slide body 68 (e.g., cross-wise and / or transverse to the longitudinal axis 62, along the vertical axis 64). The valve 102 is disposed within the cavity 104 and includes rotor mating surfaces 122 (e.g., discharge pressure surfaces, arcuate surfaces, curved surfaces, second rotor mating surfaces) that may be similar to the rotor mating surfaces 120 of the slide body 68. The rotor mating surfaces 122 of the valve 102 may be configured to at least partially define the compression chamber 58, a bypass flow path, or both based on, for example, a position of the valve 102 within the cavity 104 (e.g., relative to the slide body 68). In accordance with the present techniques, the valve 102 is configured to translate within the cavity 104 along an axis (e.g., vertical axis 64, second axis crosswise to longitudinal axis 62) transverse to the longitudinal axis 62 (e.g., axial direction). For example, the valve 102 may be adjusted (e.g., to a closed position, to an engaged position, to an activated position) to position the rotor mating surfaces 122 of the valve 102 in alignment (e.g.,New International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd along the longitudinal axis 62) with the rotor mating surfaces 120 of the slide body 68 and / or rotor bores of the housing 52. The rotor mating surfaces 122 of the valve 102 may at least partially define the compression chamber 58 (e.g., a portion of the compression chamber 58) in the activated position. For example, the valve 102 may be adjusted to the activated position during operation of the compressor 14 at full load (e.g., 100 percent capacity) to block bypass of working fluid within the compressor 14 (e.g., bypass of the compression chamber 58) and / or to adjust a volume ratio of the compressor 14. Additionally, the valve 102 may be adjusted (e.g., to an open position, to a disengaged position, to a deactivated position) to position the valve 102 further within (e.g., recessed within) the cavity 104. In the deactivated (e.g., open, disengaged) position, the rotor mating surfaces 122 of the valve 102 may be recessed within the cavity 104 and may be offset (e.g., along the vertical axis 64) from the rotor mating surfaces 120 of the slide body 68 and / or rotor bores of the housing 52. In the deactivated (e.g., open, disengaged) position, the valve 102 may enable bypass of working fluid within the compressor 14 (e.g., bypass of the compression chamber 58) and / or may adjust a volume ratio of the compressor 14. For example, the rotor mating surfaces 122 of the valve 102 may define a bypass flow path (e.g., to the suction side 54 of the compressor 14) for working fluid within the compression chamber 58 in the deactivated position of the valve 102.

[0046] As discussed in further detail below, the slide valve system 50 is also configured to enable supply and / or circulation of a fluid (e.g., lubricant, oil) within the compressor 14. For example, lubricant may be directed into the cavity 104, and at least a portion of the lubricant within the cavity 104 may be directed into the compression chamber 58 via the valve 102, such as during operation of the compressor 14 to compress a working fluid within the compression chamber 58. In some instances, at least a portion of the lubricant may be discharged from the cavity 104 via a bleed plug 124 (e.g., bleed port, bleed valve) of the valve 102. In some embodiments, a bleed port may be machined into the valve 102 (e.g., valve body) without inclusion of the bleed plug 124.

[0047] To enable desired movement of the valve 102 relative to the slide body 68 and / or desired alignment of the rotor mating surfaces 122 of the valve 102 with the rotor mating surfaces 120 of the slide body 68 and / or with the rotors 60, the valve 102 and the cavity 104 may have corresponding (e.g., matching) geometries, shapes, and / or configurations. In the illustrated embodiment, the cavity 104 and the valve 102 each have a respective non-cylindrical geometry. The corresponding, non-cylindrical geometries of the cavity 104 and the valve 102 may enable and guide translation of the valve 102 within the cavity 104 (e.g., along the vertical axis 64). TheNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd corresponding, non-cylindrical geometries of the cavity 104 and the valve 102 may also inhibit rotation of the valve 102 (e.g., about the vertical axis 64) relative to the cavity 104 and / or the slide body 68. In this way, the valve 102 may be actuated (e.g., translated) relative to the slide body 68, and proper alignment of the rotor mating surfaces 120 of the slide body 68 and the rotor mating surfaces 122 of the valve 102 (e.g., relative to one another, relative to the housing 52, relative to the rotors 60) may be achieved (e.g., in the activated position of the valve 102).

[0048] FIG. 4 is a cross-sectional side view of a portion of an embodiment of the slide valve system 50, illustrating the valve 102 (e.g., plug let-out valve [PLOV], valve body) disposed within the cavity 104 formed in the slide body 68. The valve 102 is adjustable within the cavity 104 between an activated position and a deactivated position. The cavity 104 of the slide body 68 may be configured to receive a flow of lubricant (e.g., from a lubricant source, from a lubricant sump, from another portion of the compressor 14). In some embodiments, the valve 102 may include a recess 140 formed on a side 142 of the valve 102 opposite the rotor mating surfaces 122 to form a chamber 144 (e.g., fluid chamber, working chamber, activation chamber, lubricant chamber) within the cavity 104. That is, the chamber 144 may be defined within the cavity 104 and between the valve 102 (e.g., valve body) and the slide body 68.

[0049] To actuate the valve 102 (e.g., adjust a position of the valve 102 within the cavity 104), such as to transition the valve 102 from a deactivated position to an activated position, a flow of lubricant (e.g., pressured lubricant) may be directed into the chamber 144. For example, the slide body 68 may include one or more channels, passages, grooves, or other flow paths formed therein and configured to fluidly couple to corresponding passages, grooves, or flow paths formed in the housing 52. A flow of lubricant may be supplied to the respective flow paths formed in the housing 52 and slide body 68, and the flow of lubricant may be directed into the chamber 144. In some embodiments, the housing 52 may include grooves, passages, and / or channels (e.g., lubricant supply grooves) formed therein and disposed on opposite sides of the slide bore 110 and the slide body 68 (e.g., along the lateral axis 66), and the grooves may extend along the longitudinal axis 62. The slide body 68 may include one or more cross-bores extending and / or formed through the slide body 68 (e.g., along the lateral axis 66), and the cross-bores may be configured to align with and / or fluidly couple to the grooves formed in the housing 52. The slide body 68 may also include supply ports or passages (e.g., flow paths) extending from the cross-bores of the slide body 68 to the chamber 144. Thus, the chamber 144 may be in fluid communication with the passages, grooves, or channels formed in the housing 52, and a fluid (e.g. lubricant) supplied to the channelsNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd (e.g., via a supply flow path extending through the housing 52) may be directed into the chamber 144 via the cross-bores of the slide body 68. Additionally, as the cross-bores of the slide body 68 extend along the lateral axis 66 and the grooves formed in the housing 52 on opposite sides of the slide bore 110 extend along the longitudinal axis, fluid communication between the grooves of the housing 52 and the chamber 144 may be maintained as the slide body 68 is translated within the slide bore 110.

[0050] As described further below, the lubricant within the chamber 144 may cause actuation of the valve 102 (e.g., from the deactivated position to the activated position) and may drive the valve 102 toward the compression chamber 58 (e.g., in a direction cross-wise to the longitudinal axis 62, in a direction along the vertical axis 64, toward an activated position, toward a closed position, toward an engaged position). Additionally, at least a portion of the lubricant within the chamber 144 may be directed into the compression chamber 58 via the valve 102. For example, the valve 102 (e.g., valve body) may include a lubricant flow path 146 (e.g., bore, channel, passage, fluid flow path) formed therein and / or extending through a body of the valve 102. A first portion 147 of the lubricant flow path 146 may extend from the chamber 144 to an injection port 148 of the valve 102. The injection port 148 may be exposed (e.g., fluidly coupled) to the compression chamber 58 and may be configured to direct a portion of the lubricant into the compression chamber 58. In some embodiments, the first portion 147 of the lubricant flow path 146 may include a check valve 150 (e.g., disposed within the valve 102 and along the lubricant flow path 146) to regulate and / or enable desired flow of the lubricant into the compression chamber 58 via the injection port 148. The check valve 150 may be configured to open and enable lubricant flow therethrough at a predetermined pressure, such as one bar (e.g., 100 kilopascals). In other words, the check valve 150 is configured to actuate to direct a flow of the lubricant from the chamber 144 to the compression chamber 58 in response to a pressure within the chamber 144 exceeding a threshold pressure level.

[0051] The bleed plug 124 (e.g., threaded plug, ported plug) may be disposed along a second portion 149 of the lubricant flow path 146 that is configured to direct the lubricant out of the cavity 104 for recirculation (e.g., to a lubricant sump, to a lubricant source, toward the suction side 54). In some embodiments, the bleed plug 124 may be a solid plug that does not include a bleed port. Instead, a bleed port may be formed in a body of the valve 102 (e.g., valve body) and may extend (e.g., along the vertical axis 64) from the lubricant flow path 146 toward the compression chamber 58. In this way, lubricant discharged from the lubricant flow path 146 (e.g., second portion 149)New International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd via the bleed port may be recirculated into the compression chamber 58, which may enable more efficient operation of the compressor 14.

[0052] Movement of the valve 102 within the cavity 104 (e.g., via the pressure of the lubricant within the cavity 104) may be guided via one or more pins 152 extending within corresponding grooves 154 (e.g., guide grooves) formed in the valve 102. Additionally or alternatively, the one or more pins 152 and one or more grooves 154 may be configured to engage with one another to limit a range of movement of the valve 102 (e.g., along the vertical axis 64, toward the compression chamber 58). Further, as discussed above, the valve 102 may have a non-cylindrical outer geometry 156 and / or outer contours that correspond to one or more surfaces 158 (e.g., one or more inner surfaces, one or more cavity surfaces, non-cylindrical cavity geometry) of the slide body 68 defining the cavity 104. That is, the non-cylindrical outer geometry 156 of the valve 102 (e.g., valve body) and a non-cylindrical cavity geometry of the cavity 104 (e.g., defined by the one or more surfaces 158 of the slide body 68) may correspond with and / or match one another. In this way, desired translation of the valve 102 relative to the cavity 104 and proper alignment of the valve 102 relative to the slide body 68 and the rotors 60 may be achieved and / or maintained.

[0053] FIG. 5 is a perspective view of an embodiment of the valve 102, in accordance with the aspects of the present disclosure. As described above, the valve 102 may include the rotor mating surfaces 122 and the injection port 148. Additionally, the valve 102 may have the non-cylindrical outer geometry 156 (e.g., non-cylindrical geometry) configured to match and / or mate with a corresponding non-cylindrical geometry of the cavity 104 (e.g., surfaces 158 defining the cavity 104). For example, the non-cylindrical geometry (e.g., outer geometry, lateral contour) of the valve 102 may correspond to a matching geometry of the surfaces 158 of the slide body 68 that define the cavity 104. However, other embodiments of the slide valve system 50 may include the valve 102 and the cavity 104 having different geometries that correspond with one another.

[0054] FIG. 6 is a perspective cross-sectional view of a portion of an embodiment of the compressor 14 having an embodiment of the slide valve system 50. The illustrated embodiment includes elements and element numbers similar to those described above. Additionally, the valve 102 (e.g., valve body) is illustrated in an activated or closed position. In the activated position of the valve 102, the chamber 144 defined within the cavity 104 may be pressurized with a lubricant supplied via a lubricant source 180 (e.g., lubricant sump of the compressor 14). Flow of lubricant (e.g., pressurized lubricant) from the lubricant source 180 to the chamber 144 may be regulated via a valve 182 (e.g., solenoid valve, fluid valve, lubricant valve, supply valve) disposed along aNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd lubricant supply conduit 184. Thus, the valve 182 may be in an open position to enable flow of pressurized lubricant from the lubricant source 180 into the chamber 144 via one or more lubricant inlet ports 186 (e.g., extending from cross-bores of slide body 68, lubricant supply ports, lubricant supply channels) formed in the slide body 68. In some embodiments, the lubricant supply conduit 184 may direct the flow of lubricant to one or more slots or recesses (e.g., channels, grooves) formed in the housing 52 (e.g., along the longitudinal axis 62, along the slide bore 110), and the lubricant inlet port 186 may fluidly couple to the slot formed in the housing 52 (e.g., via crossbores formed through the slide body 68) to enable supply of lubricant to the chamber 144 at each position of a plurality of positions of the slide body 68 along the longitudinal axis 62. The lubricant inlet port 186 may be formed through any suitable portion of the slide body 68 and may extend along the vertical axis 64, the lateral axis 66, the longitudinal axis 62, or any combination thereof. The housing 52 of the compressor 14 may also include one or more ports or channels to direct the lubricant from the lubricant supply conduit 184 to the lubricant inlet port 186. In some embodiments, the lubricant may be supplied to two lateral sides of the slide body 68 to balance forces of the pressurized lubricant acting on the slide valve system 50 (e.g., along the lateral axis 66).

[0055] The pressurized lubricant supplied to the chamber 144 may cause the valve 102 to transition to the activated (e.g., closed) position shown in FIG. 6. In the activated position, the rotor mating surfaces 122 of the valve 102 may be generally aligned (e.g., along the longitudinal axis 62) with the rotor mating surfaces 120 of the slide body 68. In some instances, the valve 102 may abut one or more of the pins 152 described above upon transition into the activated position. Flow of pressurized lubricant may be continuously supplied from the lubricant source 180 to the chamber 144 to maintain the valve 102 in the activated position. As the pressurized lubricant is supplied to the chamber 144, a portion of the lubricant within the chamber 144 may flow along the lubricant flow path 146 (e.g., first portion 147), across the check valve 150, and into the compression chamber 58 (e.g., an intermediate and / or axially central portion of the rotors 60) via the injection port 148. The check valve 150 may be configured to open and enable flow of lubricant from the chamber 144 into the compression chamber 58 in response to a pressure within the chamber 144 meeting or exceeding a threshold value (e.g., threshold pressure level). The check valve 150 may close and block flow of lubricant therethrough in response to the pressure within the chamber 144 falling below the threshold value.New International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd

[0056] Additionally or alternatively, another portion of the lubricant within the chamber 144 may flow along the lubricant flow path 146 (e.g., second portion 149) and may exit the valve 102 via the bleed plug 124 (e.g., bleed port) to be recirculated through a lubricant system of the compressor 14 (e.g., via the suction side 54, via the discharge side 56, via the compression chamber 58). With the valve 102 in the closed or activated position, in some instances, the compressor 14 may be operated at full load, and the slide valve system 50 may enable supply of additional lubricant into the compressor 14 in the manner described above. Additionally, the valve 102 in the closed or activated position, the compressor 14 may be operated at full load, and the slide body 68, including the valve 102, may be translated within the housing 52 along the longitudinal axis 62 to provide or obtain a desired volume ratio (e.g., lowest conventional volume ratio, lower limit volume ratio, highest conventional volume ratio, upper limit volume ratio) by positioning the radial discharge port 70 of the slide body 68 at a position corresponding to the desired volume ratio. In this way, a volume ratio of the compressor 14 may be readily and accurately adjusted with the slide body 68 during operation of the compressor 14 at a full load.

[0057] FIG. 7 is a perspective cross-sectional view of a portion of an embodiment of the compressor 14 having an embodiment of the slide valve system 50. The illustrated embodiment includes elements and element numbers similar to those described above. Additionally, the valve 102 is illustrated in a deactivated or open position. The valve 102 may be adjusted to the deactivated position to enable improved operation of the compressor 14 at a partial load (e.g., lower limit load) and / or to enable improved unloading of the compressor 14 (e.g., transition of the compressor 14 from full load operation to partial load operation).

[0058] To cause transition of the valve 102 to the deactivated position, the valve 182 disposed along the lubricant supply conduit 184 may be closed. Thus, flow of the pressurized lubricant to the chamber 144 may be suspended. Lubricant remaining within the chamber 144 may flow out of the chamber 144 and / or the cavity 104 via the lubricant flow path 146 and the bleed plug 124 and / or the injection port 148. For example, a gravitational force (e.g., in a downward direction along the vertical axis 64) and / or a force of working fluid within the compression chamber 58 acting on the rotor mating surfaces 122 may force translation of the valve 102 further into the cavity 104 (e.g., downward along the vertical axis 64), thereby reducing a volume of the chamber 144 and forcing lubricant therein to flow out of the chamber 144. The check valve 150 may also be biased in a closed position (e.g., via a pressure force from the compression chamber 58 and injection port 148) to block back flow of working fluid and / or lubricant into the lubricant flowNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd path 146 and / or the chamber 144. In the deactivated position, the valve 102 may rest on a surface 198 (e.g., base surface) of the slide body 68 within the cavity 104, and / or one of the valve 102 may rest against one or more of the pins 152. In some embodiments, the valve 102 may include a spring (e.g., coupled to the valve 102 and the slide body 68, disposed within the cavity 104, disposed within the chamber 144) configured to retract the valve 102 from the activated position to the deactivated position. Indeed, the valve 102 may be configured to transition from the activated position to the deactivated position via force of gravity, via a spring force, via a pressure force within the compression chamber 58, or any combination thereof.

[0059] With the valve 102 in the open or deactivated position, the rotor mating surfaces 122 of the valve 102 are offset (e.g., within the cavity 104, lower relative to vertical axis 64) from the rotor mating surfaces 120 of the housing 52 within the compression chamber 58 (e.g., along the vertical axis 64, along a second axis cross-wise to the longitudinal axis 62). As a result, the rotors 60 may not be fully engaged with the rotor mating surfaces 120 and / or the rotor mating surfaces 122, and at least a portion of the working fluid directed into the compression chamber 58 may bypass a flow path through the compression chamber 58 toward the discharge side 56 and / or radial discharge port 70. Instead, at least some amount of the working fluid may flow between the valve 102 and the rotors 60, as indicated by arrow 200, along a bypass flow path 202 from the compression chamber 58 to the suction side 54 of the compressor 14. Thus, the valve 102 (e.g., the rotor mating surfaces 122) may at least partially define the bypass flow path 202 in the deactivated position of the valve 102. The amount of the working fluid directed from the compression chamber 58 and along the bypass flow path 202 may be recirculated toward the suction side 54 of the compressor 14 and may not be compressed within the compression chamber 58. In this way, the compressor 14 may be unloaded and / or operated at a reduced part load (e.g., lower limit load, minimum part load) in a more desirable manner. Additionally, in embodiments of the compressor 14 having the VSD 28, operation of the slide valve system 50 in this manner may reduce a torque load on the VSD 28.

[0060] In some instances, the valve 102 may be positioned in the open or deactivated position during lubricant circulation through the compressor 14 in an idle or standstill condition (e.g., pressure equalization between the suction side 54 and the discharge side 56) of the compressor 14. During lubricant circulation through the compressor 14 in an idle or standstill condition, the slide body 68 may be adjusted to a position corresponding to a lower volume ratio (e.g., minimum volume ratio, lower limit volume ratio, a volume ratio of 1.0, to a suction end limit position). WithNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd the slide body 68 positioned in this manner, lubricant may be circulated through the compression chamber 58 (e.g., from a main lubricant injection port, via the suction side 54, via bearings of the compressor 14) and may be circulated through the compression chamber 58 to the rotors 60 (e.g., via force of gravity) without compressing the lubricant. Upon startup of the compressor, and depending on transient to steady-state operating conditions, the slide body 68 may be adjusted to a position corresponding to a higher volume ratio, while the valve 102 may be maintained in the open or deactivated position to enable bypass of working fluid and unloading of the motor 26 of the compressor 14.

[0061] It should be appreciated that the lubricant circulation operation during a standstill or idle condition may be implemented in embodiments of the compressor 14 that are configured for fixed speed operation and variable speed operation (e.g., with the VSD 28). The slide valve system 50 may also be utilized to enable improved operation in part loading conditions in embodiments of the compressor 14 that are configured for fixed speed operation. In particular, the slide body 68 may be translated toward the suction side 54, such as to a suction side limit position, with the valve 102 in a deactivated position. In this way, an amount working fluid trapped within the compression chamber 58 and between the rotors 60 may be controlled, and an amount of working fluid enabled to flow (e.g., sweep) toward the suction side 54 without compression may be adjusted.

[0062] FIG. 8 is a perspective cross-sectional view of a portion of an embodiment of the slide valve system 50 of the compressor 14, illustrating embodiments of the piston assembly 72 and the actuation system 88. The illustrated embodiment includes elements and element numbers similar to those described above. For example, the piston assembly 72 includes the cylinder 74 and the piston 76 disposed within the cylinder 74. Additionally, the actuation system 88 includes the motor 90 (e.g., stepper motor), the bearing support 100, the shaft 92, and the ball screw spindle assembly 94 having the screw shaft 96 and the nut 98 (e.g., ball screw). The screw shaft 96 and the nut 98 are also disposed within the cylinder 74, and the shaft 98 extends through the second chamber 80. The actuation system 88 also includes a magnetic coupling 220 (e.g., canned type magnetic coupling) and a gear assembly 222 configured to transfer rotational motion (e.g., rotational force, rotational movement) from the motor 90 to the screw shaft 96. As discussed above, the actuation system 88 enables more rapid, reliable, rigid, robust, and repeatable actuation (e.g., position adjustment) of the slide body 68 (e.g., utilizing a feed-forward control scheme).New International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd

[0063] FIG. 9 is a perspective cross-sectional view of an embodiment of the compressor 14 (e.g., screw compressor) including an embodiment of the slide valve system 50 (e.g., single beam slide valve, slide valve assembly) configured to enable improved control and adjustment of a volume ratio of the compressor 14. FIGS. 10 and 11 are perspective cross-sectional views of a portion of an embodiment of the compressor 14 having an embodiment of the slide valve system 50, and FIG. 12 is an axial cross-sectional view of a portion of an embodiment of the compressor 14 having the slide valve system 50. FIGS. 9-12 are discussed concurrently below.

[0064] The embodiments illustrated in FIGS. 9-12 include certain elements and element numbers similar to those described above, such as the housing 52, the slide body 68, the valve 102, and the actuation system 88. The slide valve system 50 may be configured to operate in a manner similar to that described above. For example, the slide valve system 50 includes the slide body 68 (e.g., single beam body) configured to translate within the housing 52 along the longitudinal axis 62 to adjust a volume ratio of the compressor 14. The slide body 68 also includes the cavity 104 formed therein, with an embodiment of the valve 102 (e.g., plug let-out valve) disposed within the cavity 104. The cavity 104 and the valve 102 may each include a cylindrical and / or circular geometry. In such embodiments, the slide valve system 50 may include bolts 260 (e.g., shoulder bolts, anti-rotation bolts, retention rods) coupled to the slide body 68 and extending into the valve 102. The bolts 260 may be configured to block rotation of the valve 102 relative to the slide body 68 (e.g., about the vertical axis 64). However, the valve 102 may nevertheless be configured to translate along the bolts 260 (e.g., along an axis of the bolts 260, along the vertical axis 64) to enable operation of the slide valve system 50 in the manner described herein.

[0065] The slide body 68 also includes the cavity 104 with the chamber 144 defined within the cavity 104 by the valve 102 and the slide body 68. As similarly described above, the chamber 144 is configured to receive a flow of lubricant (e.g., pressurized lubricant) to enable actuation of the valve 102 (e.g., from a deactivated position to an activated position). To this end, the slide body 68 may include one or more lubricant inlet ports 262 configured to receive a flow of pressurized lubricant and direct the flow of pressurized lubricant into the chamber 144. Flow of the pressurized lubricant into the chamber 144 may be controlled by the valve 182 described above.

[0066] The pressurized lubricant within the chamber 144 may drive translation of the valve 102 (e.g., along the vertical axis 64) to the activated (e.g., closed) position illustrated in FIGS. 10 and 12. As described above, in the activated position, the rotor mating surfaces 122 of the valve 102 may be generally aligned (e.g., along the longitudinal axis 62) with the rotor mating surfacesNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd 120 of the slide body 68, and / or the compressor 14 may be operated at full load. Additionally, at least a portion of the lubricant within the chamber 144 may flow along a lubricant port extending through the valve 102 and may be directed into the compression chamber 58 via an injection port 224 of the valve 102.

[0067] The valve 102 may be transitioned to an open or deactivated position (e.g., further extended within the cavity 104) to enable improved unloading of the compressor 14. In the illustrated embodiments, the slide valve system 50 includes a spring assembly 266 (e.g., spring return assembly, valve retraction system) configured to facilitate and enable transition of the valve 102 from the activated position to the deactivated position. The spring assembly 266 includes a spring 268 retained within a sleeve 270 via a bolt 282 and a retention cap 284 (e.g., end cap, anchor, retaining ring). The spring 268 may be in a compressed state when the valve 102 is in the activated position, as shown in FIGS. 10 and 12. Upon a decrease in pressure within the chamber 144 (e.g., when the valve 182 is closed to suspend flow of pressurized lubricant to the chamber 144), the force of the spring 268 may overcome the pressure force within the chamber 144 and may drive translation of the valve 102 further into the cavity 104 to position the valve 102 in the open or deactivated position shown in FIG. 11. To this end, the slide body 68 may include a recess 286 and the valve 102 may include a recess 288 that are aligned with one another (e.g., along the vertical axis 64) and within which the sleeve 270 and the spring 268 may translate.

[0068] During operation, at least a portion of the lubricant within the chamber 144 may flow into the recess 286, the recess 288, the sleeve 270, or any combination thereof. The valve 102 may include one or more bleed holes 290 (e.g. bleed ports), which may include one or more bleed inserts 292 disposed therein. The bleed holes 290 and / or the bleed inserts 292 are configured to enable lubricant within the recess 286, the recess 288, and / or the sleeve 270 to flow out of the valve 102 and into the compression chamber 58 in a controlled and / or regulated manner. In some embodiments, bolt retention cavities 294 of the valve 102 that accommodate the bolts 260 may also include one or more bleed holes 290 and / or one or more bleed inserts 292 to similarly enable regulated flow of lubricant into the compression chamber 58. It will be appreciated that, as the spring 268 drives translation of the valve 102 from the activated position to the deactivated position, the lubricant remaining within the chamber 144 may be ejected or drained from the chamber 144 and into the compression chamber 58 via one or more of the bleed holes 290 and / or bleed inserts 292. In some embodiments, the valve 102 may further include a check valve 296 disposed within the valve 102 and fluidly coupled to the recess 288. The check valve 296 may beNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd configured to open and enable flow of lubricant out of the chamber 144 upon a pressure within the chamber 144 meeting and / or exceeding a threshold pressure. The check valve 296 may enable flow of lubricant to the discharge side 56 of the compressor 14, to the suction side 54 of the compressor 14, or to another suitable location. Additionally or alternatively, the check valve 296 may also operate to block back flow of fluid (e.g., working fluid) from the compression chamber 58 into the chamber 144.

[0069] As set forth above, the present disclosure may provide one or more technical effects useful in operating a compressor, such as a screw compressor. In particular, embodiments of the present disclosure are directed toward a slide valve system for a compressor that enables improved control and / or adjustment of a volume ratio of the compressor, an operating capacity of the compressor, or both. The slide valve system includes a slide body (e.g., a single slide body) having a valve configured to enable more accurate and robust adjustment of the volume ratio and operating capacity of the compressor. The slide body may also be incorporated with the screw compressor in a more balanced manner that enables more rapid, responsive, and reliable adjustment of a position of the slide body within the compressor to cause a desired adjustment to the volume ratio. Moreover, the present embodiments may be implemented with reduced complexity, increased accessibility, and reduced costs compared to existing volume ratio and capacity control systems.

[0070] 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.

[0071] 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, butNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd 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.

[0072] 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).

Claims

New International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd CLAIMS:

1. A slide valve system (50) for a screw compressor (14), wherein the slide valve system (50) comprises:a slide body (68) configured to be disposed within a slide bore (110) of a housing (52) of the screw compressor (14), wherein the slide body (68) is configured to translate within the slide bore (110) along a first axis and along a compression chamber (58) of the screw compressor (14);a cavity (104) formed within the slide body (68); anda valve body (102) disposed within the cavity (104), wherein the valve body (102) is adjustable within the cavity (104) between an activated position and a deactivated position, and the valve body (102) is configured to translate along a second axis (64), cross-wise to the first axis, within the cavity (104).

2. The slide valve system (50) of claim 1, wherein the slide body (68) comprises a first rotor mating surface (120) configured to at least partially define the compression chamber (58), and the valve body (102) comprises a second rotor mating surface (122) configured to at least partially define the compression chamber (58).

3. The slide valve system (50) of claim 2, wherein the first rotor mating surface (120) and the second rotor mating surface (122) are aligned with one another along the first axis in the activated position of the valve body (102).

4. The slide valve system (50) of claim 2 or 3, wherein the second rotor mating surface (122) is offset from the first rotor mating surface (120) along the second axis (64) in the deactivated position of the valve body (102).

5. The slide valve system (50) of any of claims 1 to 4, wherein the valve body (102) is configured to define a bypass flow path (202) from the compression chamber (58) to a suction side (54) of the screw compressor (14) in the deactivated position.28New International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd 6. The slide valve system (50) of any of claims 1 to 5, comprising a chamber defined within the cavity (104) between the slide body (68) and the valve body (102), wherein the chamber is configured to receive a fluid to transition the valve body (102) from the deactivated position to the activated position.

7. The slide valve system (50) of any of claims 1 to 6, wherein the valve body (102) comprises a fluid flow path (146) formed therethrough, and the fluid flow path (146) is configured to direct a portion of the fluid within the chamber to a suction side (54) of the screw compressor (14).

8. The slide valve system (50) of any of claims 1 to 7, wherein the valve body (102) comprises a fluid flow path (146) formed therethrough, and the fluid flow path (146) is configured to direct a portion of the fluid within the chamber to the compression chamber (58) of the screw compressor (14).

9. The slide valve system (50) of any of claims 1 to 8, comprising a check valve (150) disposed within the valve body (102) and along the fluid flow path (146), wherein the check valve (150) is configured to actuate to direct a flow of the fluid from the chamber (144) to the compression chamber (58) in response to a pressure within the chamber exceeding a threshold pressure level.

10. The slide valve system (50) of any of claims 1 to 9, comprising an actuation system (88) configured to adjust a position of the slide body (68) within the slide bore (110), wherein the actuation system (88) comprises:a ball screw spindle (94);a ball nut (98) disposed about the ball screw spindle (94) and attached to a shaft (96( extending from the slide body (68), wherein the ball nut (98) is configured to convert rotary movement of the ball screw spindle (94) into linear movement; anda stepper motor (90) configured to rotate the ball screw spindle (94).

11. The slide valve system (50) of any of claims 1 to 10, comprising a piston assembly, wherein the piston assembly comprises:New International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd a cylinder (74), wherein the ball screw spindle (94) and the ball nut (98) are disposed within the cylinder (74); anda piston (76) disposed within the cylinder (74) to define and separate a first chamber and a second chamber within the cylinder (74), wherein the first chamber is configured to receive a discharge pressure of the screw compressor (14), and the second chamber is configured to receive a suction pressure of the screw compressor (14).

12. The slide valve system (50) of any of claims 1 to 11, wherein:the slide body (68) comprises a slide body (68) port extending therethrough, wherein the slide body (68) port is configured to be exposed to a discharge side (56) of the screw compressor (14),the piston (76) comprises a piston port (119) formed therethrough, andthe slide valve system (50) comprises at least one conduit extending from the slide body (68) port, through the second chamber, to the piston port (119), wherein the at least one conduit is configured to direct the discharge pressure from the discharge side (56) of the screw compressor (14) toward the first chamber.

13. The slide valve system (50) of any of claims 1 to 12, wherein the valve body (102) and the cavity (104) comprise corresponding non-cylindrical geometries.

14. A screw compressor (14), comprising:a housing (52) comprising a compression chamber (58) configured to accommodate a screw rotor (60) therein and comprising a slide bore (110); anda slide valve system (50), comprising:a slide body (68) disposed within the slide bore (110) and configured to translate within the slide bore (110) along a first axis, wherein the slide body (68) comprises a first rotor mating surface (120) configured to at least partially define the compression chamber (58), and the slide body (68) comprises a cavity (104) formed therein; anda valve body (102) disposed within the cavity (104), wherein the valve body (102) comprises a second rotor mating surface (122) configured to at least partially define the compression chamber (58), and the valve body (102) is configured to translate within the cavityNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd (104) along a second axis (64), cross-wise to the first axis (62), between an activated position and a deactivated position,wherein the first rotor mating surface (120) and the second rotor mating surface (122) are aligned with one another along the first axis (62) in the activated position of the valve body (102), and the second rotor mating surface (122) is offset from the first rotor mating surface (120) along the second axis (64) in the deactivated position of the valve body (102).

15. The screw compressor (14) of claim 14, wherein the slide valve system (50) comprises a chamber defined within the cavity (104) between the slide body (68) and the valve body (102), the chamber is configured to receive a flow of lubricant to transition the valve body (102) from the deactivated position to the activated position, the valve body (102) comprises a lubricant flow path (146) formed therethrough, and the lubricant flow path (146) is configured to direct a portion of the flow of lubricant from the chamber (144) to the compression chamber (58), a suction side (54) of the screw compressor (14), or both, in the activated position of the valve body (102).

16. The screw compressor (14) of claim 14 or 15, wherein the valve body (102) is configured to transition from the activated position to the deactivated position via a pressure within the compression chamber (58), via force of gravity, via a spring force, or any combination thereof.

17. The screw compressor (14) of any of claims 14 to 16, wherein the valve body (102) is configured to define a bypass flow path (202) from the compression chamber (58) to a suction side (54) of the screw compressor (14) in the deactivated position.

18. The screw compressor (14) of any of claims 14 to 17, wherein the slide body (68) comprises a single beam (50), the housing (52) comprises a plurality of beam supports (69) disposed therein, and the plurality of beam supports (69) is configured to support the single beam (50) at a plurality of axial locations along the single beam (50), relative to the first axis (62).

19. The screw compressor (14) of any of claims 14 to 18, wherein the valve body (102) comprises a non-cylindrical outer geometry, the cavity (104) comprises a non-cylindrical cavityNew International Application N / JOHCO-177-PCT November 12, 2025 NUGS / nusd (104) geometry, and the non-cylindrical outer geometry and the non-cylindrical cavity (104) geometry correspond with one another.

20. A screw compressor (14), comprising:a housing (52) comprising a suction side, a discharge side (56), compression chamber (58), and a slide bore (110);a screw rotor (60) disposed within the compression chamber (58) and configured to drive a working fluid through the compression chamber (58) from the suction side (54) to the discharge side (56); anda slide valve system (50), comprising:a slide body (68) disposed within the slide bore (110) and configured to translate within the slide bore (110) along a first axis (62), wherein the slide body (68) comprises a first rotor mating surface (120) configured to at least partially define the compression chamber (58), and the slide body (68) comprises a cavity (104) formed therein;a valve body (102) disposed within the cavity (104), wherein the valve body (102) comprises a second rotor mating surface (122), and the valve body (102) is configured to translate within the cavity (104) along a second axis (64), cross-wise to the first axis (62), between an activated position and a deactivated position; anda chamber disposed within the cavity (104) between the valve body (102) and the slide body (68), wherein the chamber is configured to receive a flow of lubricant to transition the valve body (102) from the deactivated position to the activated position, the valve body (102) comprises a lubricant flow path (146) formed therethrough, and the lubricant flow path (146) is configured to direct a portion of the flow of lubricant from the chamber (144) to the compression chamber (58), the suction side (54) of the screw compressor (14), or both, in the activated position of the valve body (102),wherein the second rotor mating surface (122) at least partially defines the compression chamber (58) in the activated position of the valve body (102), and the second rotor mating surface (122) at least partially defines a bypass flow path (202) from the compression chamber (58) to the suction side (54) of the screw compressor (14) in the deactivated position.32

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