Systems and methods for liquid metal bearing assembly

Abstract

A liquid metal bearing assembly and a method for operating the assembly are provided. An exemplary liquid metal bearing assembly (300) includes a channel (314) fluidly coupling a liquid metal reservoir (312) to a gap (316) between a sleeve (302) and a shaft (304), and the channel includes a first section (314a) inclined at a first angle and a second section (314b) inclined at a second angle, where the first angle is different than the second angle, and where the first section (314a) is configured to fluidly couple the liquid metal reservoir (312) to the gap (316) between the sleeve (302) and the shaft (304), and the second section (314b) is configured to fluidly couple the liquid metal reservoir (312) to the gap (316). And a curved transition section (458) is located between the first section and the second section.

Description

Technical Field

[0001] Embodiments of the subject matter disclosed herein relate to systems having liquid metal bearing assemblies and methods for assembling liquid metal bearing assemblies. Background Art

[0002] Liquid metal bearings have been used in a variety of operating environments due to their longer service life and ability to manage thermal loads more efficiently than rolling element bearings. For example, some x-ray sources or x-ray tubes employ liquid metal bearings, at least in part due to their durability and thermodynamic properties. However, asymmetric liquid metal distribution in the bearing and gas formation at the bearing-liquid metal interface can occur. Summary of the invention

[0003] In one embodiment, a liquid metal bearing assembly is provided, comprising: a channel that connects a liquid metal reservoir fluid to a gap between a sleeve and a shaft; the channel having a first section inclined at a first angle and a second section inclined at a second angle, wherein the first angle is different from the second angle, and a curved transition section is located between the first section and the second section.

[0004] The above advantages and other advantages and features of the present specification will be apparent from the following detailed description when considered alone or in conjunction with the accompanying drawings. It should be understood that the above summary is provided to introduce a series of concepts further described in the detailed description in a simplified form. This is not meant to identify key or essential features of the claimed subject matter, the scope of which is uniquely defined by the claims that follow the detailed description. In addition, the claimed subject matter is not limited to specific implementations that address any shortcomings mentioned above or in any part of this disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] The present disclosure will be better understood by reading the following description of non-limiting embodiments with reference to the accompanying drawings, in which:

[0006] Figure 1 shows a schematic block diagram of an exemplary x-ray imaging system according to one embodiment;

[0007] Figure 2 shows a pictorial view of a portion of an x-ray source according to one embodiment;

[0008] Figure 3 shows a liquid metal bearing assembly according to one embodiment;

[0009] Figure 4A Shows Figure 3 A detailed view of a section of a liquid metal bearing assembly is shown, including a liquid metal reservoir;

[0010] Figure 4B Shows Figure 3 and Figure 4A A first embodiment of a shaft of a liquid metal bearing assembly is shown;

[0011] Figure 5 shows another shaft of a liquid metal bearing assembly according to one embodiment;

[0012] Figure 6 shows another shaft of a liquid metal bearing assembly according to one embodiment;

[0013] Figure 7 Additional embodiments of shafts of liquid metal bearing assemblies are shown;

[0014] Figure 8 According to one embodiment, Figure 3 a detailed view of a section of a liquid metal bearing assembly shown, including pinning features;

[0015] Fig. 9A and Fig. 9B According to one embodiment, Figure 3 An exemplary view of a sleeve of a liquid metal bearing assembly is shown;

[0016] Fig.10 A second embodiment of a sleeve of a liquid metal bearing assembly according to one embodiment is shown;

[0017] Fig.11A , Fig. 11B and Fig. 11C Additional embodiments of liquid metal bearing assemblies according to one embodiment are shown;

[0018] Fig.12 Various views of a liquid metal bearing assembly including inserting a shaft into a sleeve are shown according to one embodiment;

[0019] Fig.13 is an exemplary method of assembling a liquid metal bearing assembly according to one embodiment;

[0020] Fig.14 Additional embodiments of shafts of liquid metal bearing assemblies are shown;

[0021] Fig.15 Additional embodiments of shafts of liquid metal bearing assemblies are shown;

[0022] Fig.16 Additional embodiments of shafts of liquid metal bearing assemblies are shown;

[0023] Fig.17Additional embodiments of liquid metal bearing assemblies are shown; and

[0024] Fig.18 Additional examples of pinning features of a liquid metal bearing assembly are shown. DETAILED DESCRIPTION

[0025] The following description relates to various embodiments of systems (e.g., x-ray imaging systems) and liquid metal bearing assemblies deployed therein. Liquid metal bearings can enable systems to achieve a desired level of liquid metal filling accuracy. Reduction of suspended gas in the liquid metal and, in some cases, more uniform liquid metal distribution at the bearing interface may be a result of the liquid metal filling accuracy. As a result, the coefficient of friction can be reduced, thereby increasing the durability and service life of the bearing.

[0026] The disclosed liquid metal bearing assembly includes a shaft and a sleeve, with a gap between the shaft and the sleeve, wherein liquid metal (such as gallium) can be introduced into the gap by capillary action. The present disclosure solves the current challenges associated with liquid metal bearing manufacturing by promoting good capillary wetting and liquid metal retention. This is achieved by introducing a gradual transition (e.g., without a sharp chamfer transition) from a gallium reservoir to the gap. The gradual transition reduces the difficulty of aligning the shaft and the sleeve, enabling self-alignment during the assembly process, thereby improving yield and reducing capacity constraints during manufacturing. For another example, the configuration of the shaft and the sleeve can reduce the reliance on lubricants sometimes used during assembly, which in some examples may contaminate gallium and interfere with the lubrication ability of gallium. In addition, a smooth transition is used on the outer surface of the thrust bearing to promote complete wetting of liquid gallium. Strategically placed pinning features can reduce the amount of gallium that may flow undesirably to the lower rotating seal and reservoir within the bearing outside the journal surface. In this way, the capillary force in the gap keeps the gallium in the gap.

[0027] X-ray imaging systems Figure 1 , and includes an x-ray source (such as an x-ray tube) configured to generate x-rays and an x-ray controller. Figure 2 An embodiment of an x-ray source is shown in which the x-ray source is configured with a liquid metal bearing to provide anode rotation. Figure 3 A first embodiment of a liquid metal bearing assembly is shown, and Figure 4A A detailed view of the channel fluidly coupling the liquid metal reservoir to the gap of the liquid metal bearing assembly is illustrated. Figure 4B A detailed view of the shaft of a liquid metal bearing assembly is shown, including the formation of Figure 4A The angled surface of the channel. Figure 5 A detailed view of another shaft of a liquid metal bearing assembly is shown. Figure 6A detailed view of another shaft of the liquid metal bearing assembly is shown, which is different from Figure 5 Axis shown. Figure 7 Additional embodiments of shafts for liquid metal bearing assemblies are shown having surfaces at different angles within the size range of the liquid metal bearing assemblies. Figure 8 Shows Figure 3 Detailed view of a section of a Liquid Metal bearing assembly, including pinning features. Fig. 9A and Fig. 9B They are shown respectively Figure 3 A first view and a second view of a sleeve of a liquid metal bearing. Fig.10 Additional configurations of sleeves are illustrated. Fig.11A , Fig. 11B and Fig. 11C Additional embodiments of liquid metal bearing assemblies are shown. Fig.12 An exemplary assembly of a liquid metal bearing assembly is shown, including inserting a shaft into a sleeve. Fig.13 A method of operating a system including a liquid metal bearing assembly is illustrated. Fig.14 , Fig.15 and Fig.16 Additional embodiments of shafts for liquid metal bearing assemblies are shown, each with surfaces at different angles within the size range of the liquid metal bearing assembly. Fig.17 Another example of a liquid metal bearing assembly is shown. In the example, the channel and the pinning feature can be in a relative orientation so that the fill port, the inlet that forms the angle and gap of the liquid metal reservoir are located on the sealing side of the liquid metal bearing, and the pinning feature is located on the opposite end of the shaft with the sleeve. Fig.18 Additional examples of pinning features of a liquid metal bearing assembly are shown.

[0028] Figures 2 to 10 , Fig.12 and Figures 14 to 16 They are drawn to scale, but other relative dimensions may be used. Figures 2 to 10 , Fig.12 and Figures 14 to 18An exemplary configuration of the relative positioning of each component is shown. In at least one example, if it is shown as being in direct contact or directly connected to each other, such elements may be referred to as being in direct contact or directly connected, respectively. Similarly, in at least one example, the elements shown as being adjacent or adjacent to each other may be adjacent or adjacent to each other, respectively. For example, components placed in coplanar contact with each other may be referred to as being in coplanar contact. For another example, in at least one example, elements positioned to be spaced apart from each other and having only space therebetween without other components may be described and referenced as such. For another example, elements shown as being located above / below each other, located on opposite sides of each other, or located on the left / right side of each other may be described and referenced as such relative to each other. In addition, as shown in the figure, in at least one example, the topmost element or the point of the element may be referred to as the "top" of the component, and the bottommost element or the point of the element may be referred to as the "bottom" of the component. As used herein, top / bottom, upper / lower, above / below may be relative to the vertical axis of the figure, and may be used to describe the positioning of the elements in the figure relative to each other. Thus, in one example, elements shown as being above other elements are positioned vertically above other elements. For another example, the shapes of the elements depicted in the figures may be referred to as having those shapes (e.g., such as being round, straight, planar, curved, rounded, chamfered, angled, etc.). In addition, in at least one example, elements shown as intersecting each other may be referred to as intersecting elements or intersecting each other. In addition, in one example, elements shown as being within another element or being shown as being outside another element may be described and referenced as such.

[0029] The liquid metal bearing assembly includes a liquid metal interface between a stationary component and a rotating component. The rotating component includes a liquid metal reservoir designed to contain liquid metal and positioned radially inward from the liquid metal interface. The rotating component additionally includes a liquid metal passage extending between the liquid metal reservoir and the liquid metal interface. The rotating component may include an anti-wetting surface in the liquid metal passage.

[0030] Before further discussing the processability of liquid metal bearing assemblies and liquid metal introduction, an exemplary x-ray imaging system that may implement a liquid metal bearing assembly is shown. Figure 1 An x-ray imaging system 100 for generating x-rays is illustrated. The x-ray imaging system 100 is configured to Figure 1The x-ray imaging system 100 may be a computer tomography (CT) imaging system, a radiographic imaging system, a fluoroscopic imaging system, a mammographic imaging system, an interventional imaging system, a tomography system, etc. However, the x-ray imaging system 100 can be applied to fields other than imaging, medical devices, etc. For example, the x-ray imaging system 100 may be deployed in a crystallographic system, a security scanner, an industrial scanner, an x-ray photography system, etc. In the x-ray imaging system example, the x-ray imaging system may be configured to image a subject 102, such as a patient, an inanimate object, one or more manufactured parts, and / or a foreign object, such as an implant, a stent, and / or a contrast agent present in the body.

[0031] The x-ray imaging system 100 may include a collector assembly having at least one x-ray source 104 (such as an x-ray tube) configured to generate and project an x-ray radiation beam 106. Specifically, in the illustrated embodiment, the x-ray source 104 is configured to project the x-ray radiation beam 106 toward a detector array 108 and through a subject 102. In some system configurations, the x-ray source 104 may project a conical x-ray radiation beam that is collimated to lie within an XYZ plane of a Cartesian coordinate system. However, other beam profiles and / or systems that omit the detector array have been contemplated. Each detector element of the array produces a separate electrical signal that is a measurement of the x-ray beam attenuation at the detector location.

[0032] although Figure 1 Only a single x-ray source 104 and detector array 108 are depicted, but in certain embodiments, multiple x-ray sources and / or detectors may be employed to project multiple x-ray radiation beams and detect the beams. For example, in a CT machine use case example, multiple detectors may be used in series with an x-ray source to acquire projection data corresponding to different energy levels of a subject.

[0033] The x-ray imaging system 100 may further include an x-ray controller 110 configured to provide power and timing signals to the x-ray source 104. It should be appreciated that the system may also include a data acquisition system configured to sample analog data received from the detector elements and convert the analog data to digital signals for subsequent processing.

[0034] In certain embodiments, the x-ray imaging system 100 may also include a computing device 112 having a processor 114 and controlling system operation based on operator input. The computing device 112 receives operator input, including, for example, commands and / or scan parameters, via an operator console 116 operatively coupled to the computing device 112. The operator console 116 may include a keyboard, a touch screen, and / or other suitable input devices that allow an operator to specify commands and / or scan parameters.

[0035] although Figure 1 Only one operator console 116 is illustrated, but more than one operator console may be included in the x-ray imaging system 100, e.g., for inputting or outputting system parameters, requesting exams, plotting data, and / or viewing images. Additionally, in certain embodiments, the x-ray imaging system 100 may be coupled to a plurality of displays, printers, workstations, and / or the like, e.g., located locally or remotely and connected via a wired and / or wireless network. In one embodiment, the display 120 may be in electronic communication with the computing device 112 and configured to display a graphical interface indicating system parameters, control settings, imaging data, and the like.

[0036] In one example, computing device 112 stores data in storage device 118. For example, storage device 118 may include a hard drive, a floppy disk drive, a compact disk-read / write (CD-R / W) drive, a digital versatile disk (DVD) drive, a flash drive, and / or a solid-state storage drive.

[0037] Additionally, the computing device 112 provides commands to the x-ray controller 110 and other system components for controlling system operations, such as x-ray beam formation, data acquisition and / or processing, etc. Thus, in certain embodiments, the computing device 112 controls system operations based on operator input. In detail, the computing device 112 can use operator-provided and / or system-defined commands and parameters to operate the x-ray controller 110, which in turn can control the x-ray source 104. In this way, the intensity and timing of x-ray beam generation can be controlled. It should also be understood that the computing device 112 can adjust the rotation speed of the sleeve in the x-ray source in conjunction with the x-ray controller 110. The sleeve can be a rotating element of a liquid metal bearing assembly, as described in detail herein.

[0038] Various methods and processes may be stored as executable instructions in non-transitory memory on a computing device (or controller) in the x-ray imaging system 100. In one embodiment, the x-ray controller 110 may include the executable instructions in the non-transitory memory and may apply the methods to control the x-ray source 104. In another embodiment, the computing device 112 may include the instructions in the non-transitory memory and may relay the commands, at least in part, to the x-ray controller 110 to adjust the x-ray source output.

[0039] Figure 2 A detailed embodiment of a portion of an x-ray source, such as x-ray tube 200, is shown. Figure 2 The x-ray tube 200 shown is used as Figure 1 An example of an x-ray source 104 is shown. Thus, Figure 2 The x-ray source shown and other x-ray source embodiments described herein may include a source from Figure 1 The functional and / or structural features of the x-ray source 104 shown are also contemplated, and vice versa. Additionally, alternative embodiments are contemplated that combine features from one or more of the systems. Figure 2 The rotation axis 250 and the radial axis 252 are provided in FIG. 2 for reference. It should be understood that the radial axis is any axis that is perpendicular to the rotation axis 250.

[0040] The x-ray tube 200 includes a housing 202 having a low pressure enclosure 204 (eg, a vacuum enclosure) formed therein. It should be understood that a low pressure enclosure means a relatively low pressure relative to atmospheric pressure. Thus, the pressure within the enclosure may be lower than atmospheric pressure.

[0041] The x-ray tube 200 includes a liquid metal bearing assembly 205 having a rotating member (herein, the rotating component 208) and a fixed component (herein, the fixed component 206). In one example, the rotating component 208 and the fixed component 206 may include a wetted surface and an anti-wetting surface. In the illustrated embodiment, the rotating component 208 is a sleeve and the fixed component 206 is a shaft. However, embodiments in which the sleeve is fixed and the shaft rotates have been envisioned. It should be understood that the motion represented by the descriptors fixed and rotating represents relative motion between the components. However, in certain use case examples, the x-ray tube may be integrated into a moving structure. For example, in a CT imaging system use case, the x-ray tube may be integrated into a rotating gantry. Therefore, in a smaller scale reference frame, the shaft is fixed relative to the sleeve, but in a larger scale reference frame, the two components exhibit similar rotational motion in the gantry. However, in an alternative use case scenario, the x-ray tube may be integrated into a fixed structure relative to a larger scale reference frame. It should also be understood that, in some cases, the liquid metal bearing assemblies described in detail herein may be deployed in alternative types of systems utilizing liquid metal bearings.

[0042] Also disposed in the x-ray tube 200 are a rotor 218 and a stator 220. The rotor 218 is coupled to the rotating component 208 and is designed to impart rotational motion thereto. The stator 220 is shown as being located outside the low voltage enclosure 204. However, other suitable stator locations are contemplated. In general, the rotor and stator may include windings, magnets, electrical connections, etc., which electromagnetically interact to respond to signals from, for example, Figure 1 An x-ray controller 110 is shown receiving control commands to generate rotor rotation.

[0043] The x-ray tube 200 also includes an anode 210 and a cathode 212. The anode 210 is part of an anode assembly. The anode 210 is coupled to and supported by a rotating member 208, which can rotate the anode 210 during x-ray beam generation. The cathode 212 is part of a cathode assembly and can be controlled by a controller such as Figure 1 An x-ray controller 110 is shown receiving signals to generate an electron beam directed toward the surface of anode 210. When the electron beam from cathode 212 strikes anode 210, an x-ray beam 214 is generated. The x-rays are emitted through an x-ray window 216 in housing 202.

[0044] As for the liquid metal bearing assembly 205, the assembly 205 includes a plurality of liquid metal bearings. In the illustrated embodiment, the liquid metal bearing assembly 205 may include a liquid metal journal bearing 222 and a liquid metal thrust bearing 224. The liquid metal journal bearing 222 is designed to support radial loads, and the liquid metal thrust bearing 224 is designed to support axial loads. In this way, the load on the sleeve (e.g., rotating component 208) can be managed to provide efficient sleeve rotation.

[0045] Each of the bearings of the liquid metal bearing assembly 205 includes an interface 226 in which the liquid metal acts as a lubricant and also supports radial and axial loads. The thickness of the interface can be selected based on factors such as the type of liquid metal used in the bearing, the manufacturing tolerances of the components, the expected system operating temperature, etc. Therefore, in one use case example, the thickness of the liquid metal interface can be approximately 5 microns (μm) to 40 μm. The thickness of the liquid metal interface of the liquid metal journal bearing 222 can be in the direction of the radial axis 252, and the thickness of the liquid metal interface of the liquid metal thrust bearing 224 can be in the direction of the radial axis 252 and in the direction of the rotational axis 250. The liquid metal used as a working fluid in the bearing assembly may include gallium, tin, indium, combinations thereof, and the like. References herein Figure 3 to Figure 1 The embodiments of the liquid metal bearing assembly described in 1 may use gallium as the liquid metal lubricant.

[0046] Figure 3An embodiment of a liquid metal bearing assembly 300 is depicted. In some examples, the liquid metal bearing assembly 300 may be used with Figure 2 The liquid metal bearing assembly 205 shown is similar or identical to the liquid metal bearing assembly 205. Therefore, the features of the liquid metal bearing assembly 205 and more generally the features of the x-ray tube 200 may be included in the liquid metal bearing assembly 300 and other liquid metal bearing assembly embodiments described herein. For comparison purposes, Figure 3 , FIG. 4A to FIG. 6 , Figures 8 to 10 and Fig.12 Axis 399 is provided in FIG. 1 . In the example shown, the y-axis is a vertical axis, the x-axis is a transverse axis (e.g., a horizontal axis) perpendicular to the y-axis, and the z-axis is a longitudinal axis perpendicular to each of the x-axis and the y-axis. The liquid metal bearing assembly 300 is mounted to an x-ray source of an x-ray imaging system (such as the one described above with reference to FIG. 1 ). Figure 1 During the depicted case of the x-ray imaging system 100 ), the x-axis is parallel to the direction of gravity. Figure 3 A first detailed view 346 and a second detailed view 348 are included.

[0047] The liquid metal bearing assembly 300 includes a rotating component (which may be referred to herein as a sleeve 302) and a fixed component (which may be referred to herein as a shaft 304). The sleeve 302 and the shaft 304 may be coupled such that the sleeve 302 may rotate relative to the shaft 304. Each of the sleeve 302 and the shaft 304 is configured with a structure that forms a liquid metal flow path during the assembly of the liquid metal bearing assembly 300, such as Figure 3 304 is enclosed in sleeve 302). The liquid metal flow path may include a fill port 310, a liquid metal reservoir 312 (e.g., a lubricant reservoir), a channel 314, and a gap 316. The fill port 310 may be machined as part of the sleeve 302 or formed (e.g., molded) with the sleeve 302 and positioned radially away from the bearing centerline. For example, the bearing centerline may be a central rotational axis 350, which is aligned with the centerline of the bearing. Figure 2The rotation axis 250 is similar or identical. The filling port may be located at a first radial distance 322 from the central rotation axis 350 (e.g., deviating from the central rotation axis 350 in the radial direction of the central rotation axis 350). In some examples, during the assembly of the liquid metal bearing assembly 300, after the liquid metal is introduced into the liquid metal reservoir 312, the filling port may be equipped with a plug (not shown). In some embodiments, the liquid metal bearing assembly 300 may be configured with more than one filling port. For example, the liquid metal bearing assembly 300 may include a filling port 310 located on a first radial side of the sleeve 302, and also include a second filling port (not shown) completely opposite to the filling port 310 relative to the central rotation axis 350 (e.g., the filling port 310 may be arranged to cross the central rotation axis 350 and be opposite to the second filling port). For another example, the second filling port may be located at an axial position different from the first filling port or parallel to the bearing axis at a different radial distance from the central rotation axis 350. In some embodiments, the filling port 310 may have a wetting coating or an anti-wetting coating.

[0048] The liquid metal reservoir 312 may extend in an annular shape around the shaft 304 as a second radial distance 324 between the shaft 304 and the sleeve 302. The liquid metal reservoir 312 may be fluidly coupled to the filling port 310 and the channel 314. Each of the liquid metal reservoir 312 and the gap 316 may hold approximately equal volumes of liquid metal. For example, the liquid metal reservoir 312 and the gap 316 may each include equal volumes of liquid gallium. As another example, the liquid metal reservoir 312 and the gap 316 may hold more liquid gallium than the volume of the filling journal gap. As a non-limiting example, the liquid metal may be approximately 5 grams. The filling port 310 coupled to the liquid metal reservoir 312 may increase the available volume of the liquid metal reservoir 312. For example, the filling port 310 may increase the liquid metal capacity. Increasing the amount of liquid metal that the liquid metal reservoir 312 can hold can improve the long-term tolerance of the bearing to undesired liquid metal flows, as well as improve desired bearing properties, such as maintaining a continuous bearing surface, as further described herein.

[0049] The liquid metal flow path including the liquid metal reservoir 312, the channel 314, and the gap 316 may have an annular configuration between the sleeve 302 and the shaft 304. The inclined diameters (e.g., tapering) of the shaft 304 and the sleeve 302 provide a narrowing of the width of the liquid flow path from the liquid metal reservoir 312 to the gap 316 (e.g., between the shaft 304 and the sleeve 302). In other words, at the channel 314, the diameter of the shaft 304 may increase relative to the diameter of the shaft 304 at the liquid metal reservoir 312, and the diameter of the interior of the sleeve 302 may decrease relative to the diameter of the interior of the sleeve 302 at the liquid metal reservoir 312, thereby reducing the overall width of the liquid metal flow path between the shaft 304 and the sleeve 302 in a direction from the second end 308 of the shaft toward the first end 306.

[0050] During assembly of the liquid metal bearing assembly 300, liquid metal may be injected or otherwise inserted into the liquid metal reservoir 312 via the fill port 310. The liquid metal may converge to the gap 316 through the channel 314. The width of the gap 316 may be less than the width of the liquid metal bead; therefore, the liquid metal may not passively flow into the gap 316. The liquid metal wets the bearing surface by allowing capillary forces to pull the liquid metal from the channel 314 into the gap 316. Therefore, the liquid metal may coat the bearing surfaces (e.g., liquid metal journal bearings and / or liquid metal thrust bearings) of the liquid metal bearing assembly 300 to create bearing surfaces having a continuous layer of liquid metal extending between the sleeve 302 and the shaft 304. This can provide smooth, uninterrupted rotation of the sleeve 302 relative to the shaft 304, such as during operation of an x-ray tube to generate an x-ray beam, as shown in reference Figure 1 and Figure 2 The liquid metal bearing assembly 300 may also include a seal in a lower region of the first end 306 of the liquid metal bearing assembly 300, designed to reduce the amount of undesirable liquid metal flow from the bearing. For example, the seal may be a rotary seal, a compression seal, etc. The seal may prevent the liquid metal from flowing away from the anode (such as Figure 2 Liquid metal flow in an axial direction (eg, along the central rotational axis 350 ) of the anode 210 ) as shown.

[0051] The sleeve 302 of the liquid metal bearing assembly 300 can be formed by a first body 302a and a second body 302b, wherein the separation of the first body 302a and the second body 302b is shown by the interface 302c. During assembly of the liquid metal bearing assembly 300, the shaft 304 is inserted into the first body 302a of the sleeve 302 from the first end 306. The body 304a of the shaft 304 is configured with a flange 304b extending radially from the body 304a of the shaft 304. The first body 302a of the sleeve 302 is configured with a complementary section 352, and the flange 304b can be located in the complementary section. When the flange 304b is located in the complementary section 352 (for example, as Figure 3 ), the second body 302b of the sleeve 302 is coupled to the first body 302a at the first end 306 to enclose the shaft 304 in the sleeve 302. The first body 302a and the second body 302b may be coupled via bolts, welding, other fasteners, etc. For example, the second body 302b may be a sleeve cap.

[0052] The first body 302a of the sleeve 302 is configured with an annular cutout in which the shaft 304 is positioned when the liquid metal bearing assembly 300 is assembled. When the shaft 304 is located in the annular cutout of the sleeve 302, a liquid metal catcher may be formed therebetween, extending the length 318 of the first body 302a and including a complementary section where the flange 304b of the shaft 304 is located. The liquid metal catcher may have an angled wall in a first region 319 of the length 318, such that a first diameter of the first region 319 gradually increases downward along the y-axis from the second end 308. The liquid metal catcher is also configured with a second diameter in a second region 320, which decreases downward along the y-axis from the channel 314 until a third region 321 of the length 318, wherein the third region 321 is a complementary section. The third diameter of the third region 321 may be greater than the second diameter of the second region 320. In other examples, the third diameter of the third region 321 may be smaller than the second diameter of the second region 320. FIG. 4A to FIG. 4B and Figure 8 to Figure 1 1 further discusses the transition between the first diameter, the second diameter and the third diameter.

[0053] The liquid metal reservoir 312 is located in a first region 319 of the trap formed by the sleeve 302 and the shaft 304. The distance between the sleeve 302 and the shaft 304 in the first region 319 is greater than the distance between the sleeve 302 and the shaft 304 at the gap 316 and the channel 314. The liquid metal reservoir 312 may have a first volume, and the gap 316 may have a second volume, wherein the second volume is greater than or equal to the first volume. The liquid metal reservoir 312 may be fluidly coupled to the gap 316 via the channel 314. As further described herein, the channel 314 includes a first section inclined at a first angle, a second section inclined at a second angle, and a curved transition section coupling the first section to the second section. In one example, the curved transition is not straight and does not include any straight sections. The first angle is different from the second angle.

[0054] A portion of the gap 316 may be arranged at a third angle, wherein the third angle is different from the first angle and the second angle. A second section of the channel 314 fluidly couples the channel 314 to the gap 316. The gap 316 may have a width between the sleeve 302 and the shaft 304 that is greater than the width of the liquid metal journal bearing 326 (e.g., Figure 2 In other embodiments, gap 316 may have different widths along the length of liquid metal journal bearing 326. In the example shown, liquid metal journal bearing 326 and liquid metal thrust bearing 328 (e.g., Figure 2 The liquid metal thrust bearing 224 of the embodiment of the present invention may have a continuous layer of liquid metal extending therein and therebetween. In one example, at the transition between the liquid metal journal bearing 326 and the liquid metal thrust bearing 328, the structure of the sleeve 302 and the shaft 304 may form a wetted reservoir 330 that couples the gap 316 to the liquid metal interface 340 of the liquid metal thrust bearing 328. In one example, the liquid metal interface 340 may be a fluid surrounding the liquid metal thrust bearing 328 that extends along a first side 332, a second side 334, and a third side 336 of the flange 304b of the liquid metal thrust bearing 328. The third side 336 of the flange 304b may be configured with a pinning feature 338. For example, the first angle of the flange 304b and the second angle of the shaft 304 in the complementary section 352 may contact to form an acute angle extending annularly therebetween. Thus, the pinning feature 338 can provide a fluid pinning and, together with capillary forces, prevent liquid metal from flowing into the gas reservoir (herein, the expansion chamber 342) formed by the second body 302b of the sleeve 302 and the shaft 304. In this way, the liquid metal reservoir 312 is fluidly separated from the expansion chamber 342 by the pinning feature 338. More details about the liquid metal reservoir 312, the channel 314, and the gap 316 will be referred to. FIG. 4A to FIG. 4BFor more details about the pinning feature 338 and the expansion chamber 342, refer to Figure 8 Give a description.

[0055] Figure 4A A detailed view 400 of a section of the liquid metal bearing assembly 300 is depicted. The detailed view 400 is similar to the first detailed view 346, including additional details of the liquid metal reservoir 312, the channel 314, and the gap 316. In one example, the sleeve 302 and the shaft 304 include structures having a geometry designed to allow the liquid metal to flow into the gap 316 during field assembly of the liquid metal bearing assembly 300. The geometry can reduce the interface between the sleeve 302 and the shaft 304 (e.g., Figure 2 The gas in the interface 226 in the bearing is formed, where the liquid metal acts as a lubricant and provides structural support. The geometry can also make the distribution of the liquid metal in the bearing assembly more uniform. In addition, the geometry can make it possible for a sufficient amount of liquid metal to flow into the bearing journal during assembly, thereby reducing underfilling and voids in the journal. The size of the reservoir is such that the entire bearing capillary gap can be filled without overflowing the fill port or rotating seal.

[0056] In one example, the liquid metal reservoir 312 widens in a direction from the second end 308 toward the first end 306. The liquid metal reservoir 312 includes a first section 312a that is narrower than the second section 312b and a third section 312c that is wider than the second section 312b. The second section 312b may be part of a gap opposite to the filling port 310, wherein the first section 312a is located above the second section and the third section 312c is located below the second section 312b. The widening of the liquid metal reservoir 312 is formed by angling the first body 302a of the sleeve 302. In the first section 312a, the inner portion 402 and the outer portion 404 of the first body 302a intersect at an angle 406, which in an example may be approximately 45 degrees. In addition, in the first section 312a, the inner portion 402 of the sleeve 302 narrows in a direction from the second end 308 toward the first end 306. Starting from angle 406, the radial width of the liquid metal reservoir 312 increases from the first section 312a to the second section 312b. At the transition between the second section 312b and the third section 312c, the liquid metal reservoir 312 increases to a first radial width 408. In one example, the first radial width 408 can hold a liquid metal bead having a diameter greater than the diameter of the channel 314 (as further described herein) near the channel 314 to promote capillary flow during field assembly.

[0057] The channel 314 fluidly couples the liquid metal reservoir 312 to the gap 316 between the sleeve 302 and the shaft 304. In one example, the channel 314 tapers in a direction from the second end 308 toward the first end 306. The taper is formed by widening the shaft 304. For example, the shaft 304 may have a second radial width 410 in the area of ​​the liquid metal reservoir 312. The shaft 304 widens in the area of ​​the channel 314 to a third radial width 412 in the area of ​​the gap 316. The widening of the shaft 304 from the second radial width 410 to the third radial width 412 includes a first angle, a second angle, a curved transition between the first angle and the second angle, and a third angle. The angle of the shaft 304 is as shown in FIG. Figure 4B shown.

[0058] The angled surface of shaft 304 relative to sleeve 302 affects the geometry of passage 314. Figure 4B 314a and 314c. In one example, the channel 314 includes a first section 314a inclined at a first angle, a second section 314c inclined at a second angle different from the first angle, and a curved transition 314b between the first section 314a and the second section 314c. The gap 316 can be inclined at a third angle. In one example, the angled surface of the shaft 304 forms the channel 314 so that the liquid metal bead is kept above the gap 316 during field assembly. When the liquid metal bead is heated during use, the tapered geometry of the channel 314 and the gap 316 further increases the capillary flow during assembly. For example, the size of the first section 314a is such that the liquid metal can contact the second section 314c, thereby allowing capillary flow. Therefore, the liquid metal entering the gap 316 (e.g., a journal) can be controlled by the specific wetting properties of the shaft chamfer (e.g., the transition edge between the two faces of the object).

[0059] Figure 4B A detailed view 450 of a section of a liquid metal bearing assembly 300 is depicted. The detailed view 450 includes additional details of the shaft 304. In one example, the shaft 304 includes an angled surface designed to allow liquid metal to flow into the gap 316 during field assembly of the liquid metal bearing assembly 300. This geometry can reduce gas formation in the bearing journal (e.g., gap 316), where the liquid metal acts as a lubricant and provides structural support. The geometry can also make the distribution of the liquid metal in the assembly more uniform. The geometry of the structure also facilitates automatic alignment of the shaft and sleeve during field assembly, thereby improving manufacturing efficiency.

[0060] The shaft 304 includes an upper section 452. The upper section 452 of the shaft 304 may be adjacent to the liquid metal reservoir 312 (e.g., at Figure 3, etc.). Step 454 may be located below upper section 452. In one example, step 454 may be a ground step. Below step 454, shaft 304 is formed with a gradual transition 464. Gradient transition 464 includes first section 456, curved transition 458, second section 460, and third section 462. In one example, gradual transition 464 may be adjacent to channel 314 and the transition between channel 314 and gap 316 (e.g., at Figure 3 in, etc.).

[0061] In one example, the first section 456 may be inclined at a first angle 456a ranging from a lower boundary of 45° to an upper boundary of 60°. The first section 456 may have a first axial length 456b ranging from a lower boundary of 0.5 mm to an upper boundary of 3 mm. Here the axial length is in the direction of the axis of rotation (e.g., parallel to the axis of rotation). The first section 456 may have a first radial variation 456c ranging from a lower boundary of 1 mm to an upper boundary of 2 mm. In one example, the length of the curved transition 458 ranges from 4 mm to 9 mm. In one example, the second section 460 may be inclined at a second angle 460a ranging from a lower boundary of 0.5° to an upper boundary of 15°. The second section 460 may have a second axial length 460b ranging from a lower boundary of 1.5 mm to an upper boundary of 7 mm. The second section 460 may have a second radial variation 460c ranging from 0.5 mm to 1 mm. In one example, the third section 462 may be inclined at a third angle 462a ranging from a lower limit of 0 degrees to an upper limit of 2.5 degrees. The third section 462 may be the length of a journal of the assembly. In one example, the radius at the first radial change 456c is less than the radius at the second radial change 460c, and the difference is equal to the length of the second radial change 460c.

[0062] In one example, the first angle 456a, which is greater than the second angle 460a, acts as a funnel to move liquid metal from the liquid metal reservoir 312 to the channel 314 and into the gap 316 (e.g., a bearing journal). The size of the first angle 456a allows the liquid metal bead to fit further into the channel 314, thereby reducing the distance between the channel 314 and the gap 316 to increase capillary flow. The second angle 460a and the corresponding geometry of the sleeve 302 allow for automatic alignment during assembly. Fig.12 The geometry of this shaft and sleeve is described in more detail in .

[0063] Figure 5 It is shown that the liquid metal bearing assembly (such as Figure 3Detailed view 550 of another embodiment of a shaft 500 implemented in a liquid metal bearing assembly 300 of FIG. 500 is similar in form and function to the shaft 500 of FIG. Figure 3 , Figure 4A and Figure 4B The shaft 304 shown is relatively similar. In one example, the dimensions of the shaft 500 and the dimensions of the additional shaft embodiments illustrated below can be found in reference to Figure 3 , FIG. 4A to FIG. 4B Within the described size range.

[0064] For example, shaft 500 includes a gradual transition 502 including a first segment 504 inclined at a first angle 504a, a second segment 508 inclined at a second angle 508a, a curved transition 506 between the first segment 504 and the second segment 508, and a third segment 510 inclined at a third angle 510a. Figures 3 to 4B Compared to the embodiment of shaft 304 in FIG. , the gap in the embodiment of shaft 500 (e.g., Figure 3 The first angle 504a, the second angle 508a and the third angle 510a of the axis at the gap 316 in the reference yoke may be different. In one example, the first angle 504a may be greater than the reference yoke. Figure 4B In one example, the second angle 508a may be greater than the reference angle 456a. Figure 4B A second angle 460a is shown.

[0065] The first segment 504 may have a first axial length 511. The curved transition 506 and the first segment 504 may together have a second axial length 512. The first segment 504, the curved transition 506, and the second segment 508 may together have a third axial length 514. The third segment 510 may have a fourth axial length 516. The first segment 504, the curved transition 506, the second segment 508, and the third segment 510 may together have a fifth axial length 518. In this example, the first axial length 511 of the shaft 500 may be similar to that of the reference numeral 504. Figure 4B The length range described by the first axial length 456b of the shaft 304 in FIG. In this example, the first axial length 511 may be shorter than the first axial length 456b of the shaft 304. In other examples, the first axial length 511 may be greater than the first axial length 456b. Similarly, the difference between the second axial length 512 and the third axial length 514 may be similar to Figure 4B The length range described in for the second axial length 460b of the shaft 304.

[0066] Figure 6 It is shown that the liquid metal bearing assembly (such as Figure 3 Another embodiment of the shaft 600 implemented in the liquid metal bearing assembly 300 of FIG. The shaft 600 is similar in form and function to the Figure 3, Figure 4A and Figure 4B The shaft 304 and Figure 5 The illustrated shaft 500 is relatively similar. Figure 6 Axis of rotation 602 is provided for reference. Axis of rotation 602 may be Figure 3 and Figure 4A The rotation axis 350 in is the same or similar.

[0067] Figure 6 Detailed view 650 of shaft 600 is included, including gradual transition 620. Gradual transition 620 includes first segment 606 inclined at first angle 606a, second segment 610 inclined at second angle 610a, and third segment 612. Curved transition 608 may be located between first segment 606 and second segment 610. In other examples, angled segments (e.g., first segment 606 and second segment 610) may transition directly to each other without a curved transition. In some examples, shaft 600 may include tool transition region 604. Figures 3 to 4B and Figure 5 Compared to the illustrated shaft embodiment, the gap in the embodiment of shaft 600 (e.g., Figure 3 The first angle 606a, the second angle 610a and the third angle 612a of the axis at the gap 316) may be different. For example, the first angle 606a may be smaller than the first angle 504a, and the second angle 610a may be smaller than the second angle 508a, as shown in FIG. Figure 5 In one example, the gradual transition 620 may have a length 614. In one example, the length 614 may be shorter than the third axial length 514, as shown in FIG. Figure 5 described.

[0068] Figure 7 It is shown that the liquid metal bearing assembly (for example, Figure 3 Another embodiment of a shaft 700 implemented in a liquid metal bearing assembly 300 of FIG. 1 , wherein the angles used to form a channel coupling the liquid metal reservoir to the gap are shown in detail.

[0069] The shaft 700 includes a first section 702, a second section 706, a curved transition 704 between the first section 702 and the second section 706, and a third section 714. The shaft 700 includes a first angle 702a and a second angle 706a. The first section 702 includes a first axial length 708. The second section 706 includes a second axial length 712. The second section 706 and the curved transition 704 have a combined axial length 710. The first angle 702a and the second angle 706a of the shaft 700 can be respectively referenced to Figures 3 to 4B , Figure 5 and Figure 6The first angle and the second angle of the axis 304, the axis 500 and the axis 600 are shown to be different. For example, the first angle 702a may be greater than the reference angle 702a. Figure 5 As another example, the second angle 706a may be greater than the reference angle 504a. Figure 6 The second angle 610a is depicted. In one example, the shaft 700 includes a cutout 716 .

[0070] Figure 8 A detailed view 800 of a section of the liquid metal bearing assembly 300 is shown. The detailed view 800 may be similar to the second detailed view 348, including additional details of the wetted reservoir 330, the pinning feature 338, and the expansion chamber 342. In particular, the detailed view 800 illustrates features of the liquid metal bearing assembly that may reduce undesirable liquid metal flow in the assembly.

[0071] In one example, the third side 336 of the flange 304b can be in coplanar contact along the face 804 of the second body 302b. The flow of liquid metal outside the liquid metal interface 340 between the third side 336 and the face 804 can be prevented or reduced by the acute angle 802, which acts as a discontinuity point that changes the capillary force after the discontinuity point. The first angled cutout 806 on the third side 336 of the flange 304b and the second angled cutout 808 on the face 804 of the second body 302b extend annularly in a contacting manner to form the acute angle 802. The acute angle 802 formed by the straight transition between the first angled cutout 806 and the second angled cutout 808 can keep the liquid metal at the intersection of the two sides and can reduce the incidence of liquid metal entering the lower rotating seal, which may cause undesirable flow due to gas pressure and complete wetting of the bearing journal. In one example, the first angled cutout 806 and the second angled cutout 808 may be substantially symmetrical and form a sharp point. In another example, two asymmetrical cutouts may form a sharp point that acts as a pinning feature. In one example, the first angled cutout 806 and the second angled cutout 808 intersect at an approximately right angle at the acute angle 802. Therefore, the pinning feature 338 can provide a fluid pinning and prevent liquid metal from flowing into the expansion chamber 342 together with the capillary force. In one example, the pinning feature 338 separates the expansion chamber 342 from the wetting reservoir fluid. As another example, the pinning feature can be achieved by creating an undercut on the surface. Fig.18 An example of an undercut surface forming a pinning feature is shown.

[0072] The expansion chamber 342 may be formed by the second body 302b of the sleeve 302 and the shaft 304. The expansion chamber 342 may be defined by the inner surface of the liquid metal bearing assembly 300, which forms a void having an annular geometry. For example, the first surface 810 of the second body 302b may form the outer boundary of the expansion chamber 342. The second surface 812 and the fourth surface 830 of the shaft 304 may form the inner boundary of the expansion chamber 342. The third surface 816 of the flange 304b, which may be continuous with the first angled cutout 806, may form the upper boundary of the expansion chamber 342. The recess 814 shapes the first surface 810 toward the first end 306 of the liquid metal bearing assembly 300 and may form the lower boundary of the expansion chamber 342. The expansion chamber 342 (ideally free of liquid metal) may act as a gas reservoir to retain liquid metal exhaust gases.

[0073] The wetting reservoir 330 can fluidly connect the gap 316 and the liquid metal interface 340 surrounding the flange 304b. The wetting reservoir 330 can be formed by the first body 302a of the sleeve 302 and the shaft 304. The wetting reservoir 330 can be defined by the inner surface of the liquid metal bearing assembly 300, which forms a gap having an annular geometry. For example, the fourth surface 818 of the first body 302a can form the outer boundary of the wetting reservoir 330. The fifth surface 820 of the shaft 304 can form the inner boundary of the wetting reservoir 330. The fifth surface 820 can be shaped to avoid sharp transitions, wherein, for example, the bottom 822 of the wetting reservoir 330 can be relatively lower than the first side 332 of the flange 304b (e.g., along the y-axis) and gradually slopes to the liquid metal interface 340. The shape of the wetting reservoir 330 provides a smooth transition to facilitate liquid metal thrust bearings (e.g., Figure 2 The geometry of the wetted reservoir 330, in combination with the pinning feature 338, holds the liquid metal in the gap 316 and the liquid metal interface 340, thereby enabling the introduction of a sufficient amount of liquid metal during field assembly while minimizing underfill and voids in the flow path.

[0074] Fig. 9A and Fig. 9B It is shown that the liquid metal bearing assembly (such as Figure 3 A perspective view of a sleeve implemented in a liquid metal bearing assembly 300). In one example, Fig. 9A A first perspective view 900 of a sleeve (eg, sleeve 302 ) that may be disposed along a second end (eg, second end 308 ) of a bearing assembly is shown. Fig. 9B A second perspective view 950 of a sleeve that may be disposed along a first end (eg, first end 306 ) of a bearing assembly is shown.

[0075] First go to Fig. 9A, a first perspective view 900 of a first side 902 of a sleeve shows an example of a first surface 906 and a second surface 908. The first surface 906 can be joined to the second surface 908 by a step 910. The step 910 can include an inclined (e.g., curved or angled) edge 904. In some examples, the step 910 can be angularly oriented relative to the axis of rotation (e.g., Figure 2 The rotation axis 250 in FIG. 2 is angled (eg, an angle between 0.5° and 15°). In some examples, forming an angle can reduce the incidence of component deformation.

[0076] Fig. 9B A second perspective view 950 of an example of a second body 952 of a sleeve is shown, which may be similar to the second body 302b of the sleeve 302. The second body 952 includes a first surface 954 and a second surface 956 joined by a first step 962. In one example, the first step 962 can be arranged approximately perpendicular to the first surface 954 and the second surface 956. The second body 952 includes a third surface 958 joined to the second surface 956 by a second step 960. In one example, the second step 960 can be arranged approximately perpendicular to the second surface 956 and the third surface 958. The second step 960 may include a rounded edge 968.

[0077] The first surface 954 may include an inner cylindrical surface 964, an opening 970 on the first surface 954, and an opening on the opposite surface (e.g., Figure 8 The plurality of through holes 966 are defined by the openings 826 on the opposing surfaces 824 in the embodiment. In one example, the fastener (e.g., Figure 8 Bolts 828 in the sleeve can be inserted through the through holes 966 to secure the second body 952 to the first body of the sleeve (e.g., the first body 302a) during field assembly.

[0078] Fig.10 It is shown that the liquid metal bearing assembly (such as Figure 3 Another embodiment of the sleeve 1000 implemented in the liquid metal bearing assembly 300 of the embodiment of the present invention. The sleeve 1000 is similar in form and function to the Figure 3 , Fig. 9A and Fig. 9B The illustrated sleeve 302 is relatively similar.

[0079] In one example, the inner surface of the sleeve 1000 may be processed in various ways to have different surface finishes. For example, a first area of ​​the sleeve radially surrounded by the inner surface of the shaft may have a first surface finish. A second area of ​​the sleeve not radially surrounded by the inner surface of the shaft may have a second surface finish different from the first surface finish. In one example, the first surface 1002 of the sleeve 1000 may include a turned section and a ground section. For example, the sleeve 1000 may have a first area 1004, which is formed to be approximately cylindrical and has a first length 1006. For another example, the second area 1008 of the first surface 1002 may be ground to a second length 1010, and the third area 1012 may be turned to a third length 1014. The sleeve 1000 may be formed to have an uncontrolled cylindrical shape along the second length 1010. The grinding interface 1016 between the second length 1010 and the third length 1014 may produce a step or discontinuity 1018.

[0080] The first surface 1002 of the sleeve 1000 can be formed to include a first angle 1024 and a second angle 1022. In one example, the first angle 1024 can be 30° to 60°, and the second angle 1022 can range from 0.5° to 15°. In one example, the geometry of the sleeve 1000 can reduce the possibility of liquid metal being retained in a liquid metal reservoir (e.g., during a wetting and coating step of manufacturing) during field assembly. Figure 3 The occurrence rate in the liquid metal reservoir 312, etc.

[0081] Fig.11A , Fig. 11B and Fig. 11C 110, 1140, and 1170, respectively, of a liquid metal bearing assembly 1100. The examples of the liquid metal bearing assembly 1100 are functionally similar to Figure 3 , Figure 4A The liquid metal bearing assembly 300 shown in FIG. 110 , the second example 1140 , and the third example 1170 illustrate exemplary modifications to the liquid metal bearing assembly 1100 that may increase capillary flow of liquid metal into the bearing journal and facilitate automatic alignment of shaft insertion during field assembly.

[0082] Liquid metal bearing assembly 1100 includes shaft 1102, sleeve 1104, fill reservoir 1106, and bearing gap 1108. Fill reservoir 1106 may include a void formed by the shaft 1102 and the inner surface of sleeve 1104. For example, the surface may include a first surface 1102a of shaft 1102 and a second surface 1104a of sleeve 1104.

[0083] Fig.11AA first example 1110 is shown that includes a first modification 1112. The first modification 1112 may be a cutout cut out of the shaft 1102 that enlarges the fill reservoir 1106.

[0084] Fig. 11B A second example 1140 is shown including a first modification 1112 and a second modification 1142. The second modification 1142 may be a modification of the second surface 1104a of the sleeve 1104 (eg, see Fig.11A The second modification 1142 and the first modification 1112 enlarge the filling reservoir 1106 and widen the angle 1144 of the bearing gap 1108.

[0085] Fig. 11C A third example 1170 is shown including a third modification 1172, a fourth modification 1174, a fifth modification 1176, and a sixth modification 1178. The third modification 1172 may be a first modification 1112 from the shaft 1102 (e.g., see Fig.11A ) cut out. The fourth modification 1174 and the fifth modification 1176 may be cut out from the first surface 1102a of the shaft 1102. The sixth modification 1178 may be a cut out from the second modification 1142 (see, for example, Fig. 11B ). These modifications enlarge the fill reservoir 1106 and widen the angle 1180 of the bearing gap 1108.

[0086] FIG. 11A to FIG. 11C The exemplary modifications shown may have various advantages. For example, by widening the filling reservoir 1106, these modifications allow for adequate liquid metal filling prior to wetting. As another example, by reducing the chamfers in the filling reservoir 1106, these modifications increase capillary flow to the bearing gap 1108. In addition, reducing chamfers and other sharp transitions may reduce galling and other wear that may occur between the sliding surfaces of the shaft 1102 and the sleeve 1104 during field assembly.

[0087] Fig.12 An assembly sequence 1200 of a liquid metal bearing assembly 300 is shown during the insertion of a shaft 304 into a sleeve 302. For example, a first position 1202, a second position 1204, and a third position 1206 of the shaft 304 and sleeve 302 during field assembly are shown. For example, the matching angles of the sleeve 302 and the shaft 304 are aligned to facilitate assembly. For example, the matching angles can automatically align the shaft 304 and sleeve 302 during field assembly, thereby improving manufacturing efficiency.

[0088] The gradual transition 464 of the shaft 304 is shown as including segments formed with compound angles, such as the first segment 456, the second segment 460, and the third segment 462 and the curved transition 458. The second segment includes a second angle 460a. The first region 1208 of the first body 302a of the sleeve 302 can be formed to have a sleeve angle 1208a that can be the same or similar to the second angle 460a. Dashed lines 1210, 1212 are drawn to illustrate the gap 316 or bearing journal between the shaft 304 and the sleeve 302. The second angle 460a and the sleeve angle 1208a can be cutouts cut out from the gap 316.

[0089] During assembly, the shaft 304 can be inserted into the sleeve 302 from the first end 306. During assembly, at the first position 1202, the shaft 304 is close to the first area 1208 of the sleeve. At the second position 1204, the shaft 304 passes through the first area 1208 of the sleeve 302. The second angle 460a and the sleeve angle 1208a match and the cutout cut from the gap 316 enable the shaft 304 and the sleeve 302 to slide against each other. When the shaft 304 passes through the first area 1208 of the sleeve 302, the distance between the two narrows to the gap 316. At the third position 1206, the shaft 304 is fully inserted into the sleeve 302. For example, once fully inserted so that the shaft 304 intersects the second end 308 of the assembly, a liquid metal reservoir 312, a channel 314, and a gap 316 can be formed for receiving liquid metal or other bearing lubricants.

[0090] Fig.13 A flow chart illustrating an exemplary method 1300 of a liquid metal bearing assembly is shown. In one example, the liquid metal bearing assembly may be liquid metal bearing assembly 300. In one example, method 1300 may be performed by an automated system for assembling a liquid metal bearing assembly.

[0091] In one example, at 1302, method 1300 may include coupling a shaft to a sleeve of a liquid metal bearing assembly by inserting the shaft into the sleeve at an opening at a first end of the sleeve. For example, one or more angled surfaces or compound angles of the shaft and matching angles of the sleeve may allow for automatic alignment during assembly.

[0092] At 1304, method 1300 may include coupling a sleeve cap to the first end of the sleeve. For example, the sleeve cap may be the same or similar to the second body 302b, and the first end of the sleeve may be coupled to the sleeve cap. Figure 3 and Figure 8302a described in . For example, by joining the sleeve cap to the first end of the sleeve, a first reservoir (e.g., a liquid metal reservoir) can be formed at the first end of the assembly (e.g., the second end 308), and a second reservoir (e.g., a gas reservoir, an expansion chamber 342) can be formed at the second end (e.g., the first end 306). In addition, when joined, the flange of the shaft and the complementary section of the sleeve form a pin-joined feature with an acute angle formed at the interface therebetween. For example, when joined, the sleeve and the shaft can form a liquid metal reservoir 312, a wetted reservoir 330, a pin-joined feature 338, and an expansion chamber 342.

[0093] At 1306, method 1300 may include injecting liquid metal into the liquid metal reservoir via a fill port located at the second end of the assembly. Liquid metal, such as gallium, may be an example of a lubricant that may be used as a bearing in a liquid metal bearing assembly. The fill port may be similar to Figure 3 and the filling port 310 shown in other figures. In one example, a certain amount of liquid metal can be injected into the liquid metal reservoir, which amount can be equal to the volume of the liquid metal reservoir. In some examples, liquid metal can be additionally injected into the reservoir so that the total volume of the injected metal exceeds the volume of the reservoir.

[0094] At 1308, method 1300 may include heating the liquid metal bearing assembly to create a bearing surface in the gap between the sleeve and the shaft, thereby using capillary forces to cause liquid metal to flow into the gap. In other words, the liquid metal can be pulled into the gap from the liquid metal reservoir by capillary forces. Capillary forces can pull the liquid metal into the gap without heating. In some examples, the liquid metal bearing may not be heated during assembly. For example, the liquid metal can be blocked (e.g., reduced, prevented) from flowing into the expansion chamber by a pinning feature formed between the shaft and the sleeve.

[0095] Fig.14 , Fig.15 and Fig.16 It is shown that the liquid metal bearing assembly (for example, Figure 3 Another embodiment of a shaft implemented in a liquid metal bearing assembly 300) is shown in detail, wherein the angles used to form a channel connecting the liquid metal reservoir to the gap are shown. In one example, reference Figures 14 to 16 The dimensions of another embodiment of the described shaft can be found in reference Figure 3 , FIG. 4A to FIG. 4B Within the described size range.

[0096] Fig.14A shaft 1400 is shown. The shaft 1400 includes a first section 1402, a second section 1408, a curved transition 1404 between the first section 1402 and the second section 1408, and a third section 1422. The shaft 1400 includes a first angle 1412, a second angle 1414, and a third angle 1416. The first section 1402 has a first axial length 1410. The second section 1408 has a second axial length 1406. The curved transition 1404 has a transition axial length 1420. The shaft 1400 has a third axial length 1418 and includes the first section 1402, the second section 1408, the curved transition 1404, and the third section 1422.

[0097] In some examples, the first angle 1412, the second angle 1414, and the third angle 1416 may be different from the reference angle. Figures 3 to 4B , Figure 5 , Figure 6 and Figure 7 The first angle, second angle, and third angle of various embodiments of the shaft shown. For example, the first angle 1412 may be less than the reference Figure 5 The first angle 504a is described. The first angle 1412 may be greater than the reference Figure 6 The second angle 1414 may be greater than the reference angle 606a. Figure 5 A second angle 508a is depicted.

[0098] In some examples, the first axial length 1410, the second axial length 1406, the transition axial length 1420, and the third axial length 1418 may be different from the reference axial length. Figures 3 to 4B , Figure 5 , Figure 6 and Figure 7 The corresponding axial lengths of various embodiments of the shaft shown. For example, the first axial length 1410 can be longer than the reference Figure 5 The first axial length 511 described. The third axial length 1418 may be shorter than the reference Figure 5 The fifth axial length 518 is described. As another example, the first axial length 1410 may be longer than the reference Figure 7 A first axial length 708 is depicted.

[0099] Fig.15A shaft 1500 is shown. The shaft 1500 includes a first section 1502, a second section 1504, a third section 1508, and a curved transition 1506. The shaft 1500 includes a first angle 1510, a second angle 1512, and a third angle 1514. The first section 1502 has a first axial length 1524. The curved transition 1506 and the first section 1502 have a second axial length 1516. The first section 1502, the second section 1504, a portion of the third section 1508, and the curved transition have a third axial length 1520.

[0100] In some examples, the first angle 1510, the second angle 1512, and the third angle 1514 may be different from the reference angle. Figures 3 to 4B , Figures 5 to 7 and Fig.14 For example, the first angle 1510 may be greater than the reference angle 1520. Fig.14 The first angle 1412 is described. The first angle 1510 may be greater than the reference Figure 5 and Figure 6 The second angle 1512 may be smaller than the reference angle 504a. Figure 5 A second angle 508a is depicted.

[0101] In some examples, the first axial length 1524, the second axial length 1516, and the third axial length 1520 may be different from the reference Figures 3 to 4B , Figure 5 , Figure 6 and Figure 7 The corresponding axial lengths of various embodiments of the shaft are shown. For example, the first axial length 1524 may be shorter than the reference Figure 7 The third axial length 1520 may be longer than the reference Fig.14 A third axial length 1418 is described.

[0102] Fig.16 Axis 1600 is shown. Axis 1600 includes a first segment 1602, a second segment 1604, and a third segment 1608. Axis 1600 includes a first angle 1610 and a second angle 1612. In some examples, first angle 1610 and second angle 1612 may be different from reference angles. Figures 3 to 4B , Figures 5 to 7 and Figure 14 to Figure 15 The first angle and the second angle of the various embodiments of the shaft shown. For example, the second angle 1612 can be less than the reference Fig.14 The axis 1600 does not include a curved transition between the first angle 1610 and the second angle 1612 (e.g., Fig.14In other examples, the axis 1600 can include a curved transition between the first angle 1610 and the second angle 1612.

[0103] Fig.17 An example of a liquid metal bearing assembly 1700 is shown. Liquid metal bearing assembly 1700 is one configuration of the disclosed liquid metal bearings in which the assembly is arranged in an alternative orientation (e.g., with Figure 3 In this example, the fill port and the pinning feature can be in opposing orientations such that the fill port and the angle creating the reservoir and gap access are located on the sealing side of the bearing, such as the first end 1706, and the pinning feature is located on the opposite end of the shaft with the sleeve, such as the second end 1708.

[0104] The liquid metal bearing assembly 1700 includes a sleeve 1702 and a shaft 1704. In one example, the sleeve 1702 may be a rotating component and the shaft 1704 may be a fixed component. The sleeve 1702 and the shaft 1704 may be coupled so that the sleeve 1702 may rotate relative to the shaft 1704. The sleeve 1702 of the liquid metal bearing assembly 1700 may be composed of a first body 1702a and a second body (not shown, for example). Figure 3 The main body 1704a of the shaft 1704 is configured with a flange 1704b extending radially from the main body 1704a of the shaft 1704. The first body 1702a of the sleeve 1702 is configured with a complementary section 1722 in which the flange 1704b can be located.

[0105] Each of the sleeve 1702 and the shaft 1704 is configured with a structure that forms a liquid metal flow path during the assembly of the liquid metal bearing assembly 1700. The liquid metal flow path may include a filling port 1710, a first reservoir 1712 (e.g., a liquid metal reservoir, a gallium reservoir), a channel 1714, and a gap 1716. During assembly, liquid metal may be introduced into the first reservoir 1712 via the filling port 1710. The channel 1714 may include an angle that facilitates flow from the first reservoir 1712 into the gap 1716. The filling port 1710, the first reservoir 1712, and the channel 1714 are arranged at the first end 1706 of the liquid metal bearing assembly 1700.

[0106] Sleeve 1702 includes a pinning feature including sleeve element 1752 and shaft element 1750. Sleeve element 1752 and shaft element 1750 reduce the flow of gallium into undesirable areas of the liquid metal bearing assembly 1700 by pinning the gallium in gap 1716. Sleeve element 1752 and shaft element 1750 are disposed at a second end of the liquid metal bearing assembly 1700.

[0107] During assembly of the liquid metal bearing assembly 1700, the shaft 1704 is inserted into the first body 1702a of the sleeve 1702 from the first end 1706. When the flange 1704b is located in the complementary section 1722 (e.g., as shown in FIG. Fig.17 1704 ), the second body of the sleeve 1702 can be coupled to the first body 1702a at the first end 1706 to enclose the shaft 1704 in the sleeve 1702. The first body 1702a and the second body can be coupled via bolts, welding, other fasteners, etc. For example, the second body can be a sleeve cap. In this way, the filling port 1710 and the first reservoir 1712 are arranged on the sealing side of the bearing, and the pinning feature is arranged on the opposite end of the bearing between the shaft 1704 and the sleeve 1702.

[0108] Fig.18 An example of a liquid metal bearing assembly 1800 is shown. The liquid metal bearing assembly 1800 is one configuration of the disclosed liquid metal bearings showing additional or alternative pinning features. The liquid metal bearing assembly 1800 may be similar in other respects to the above referenced Figures 2 to 17 The examples of liquid metal bearing assemblies described are the same or similar.

[0109] The liquid metal bearing assembly 1800 includes a sleeve 1802 and a shaft 1804. In one example, the sleeve 1802 may be a rotating component and the shaft 1804 may be a fixed component. The sleeve 1802 and the shaft 1804 may be coupled so that the sleeve 1802 may rotate relative to the shaft 1804. The sleeve 1802 of the liquid metal bearing assembly 1800 may be composed of a first body 1802a and a second body (not shown, for example). Figure 3 The main body 1804a of the shaft 1804 is configured with a flange 1804b extending radially from the main body 1804a of the shaft 1804. The first body 1802a of the sleeve 1802 is configured with a complementary section 1814 in which the flange 1804b can be located.

[0110] A gap 1816 is formed between sleeve 1802 and shaft 1804. Liquid metal introduced during assembly can fill gap 1816. Liquid metal can be prevented from flowing through gap 1816 by a pinning feature that separates gap 1816 from a gas reservoir indicated by arrow 1806. The placement and geometry of the pinning feature can help reduce the amount of liquid metal of the lower rotating seal and reservoir within the bearing that may undesirably flow to the outside of the journal surface. In this example, a first pinning feature 1824 and a second pinning feature 1834 are shown in the same bearing assembly. However, it is understood that the manufactured bearing assembly may include only one of the first pinning feature 1824, the second pinning feature 1834, the pinning feature 338, or other similar configurations.

[0111] The first pinning feature 1824 includes a first sleeve element 1820 and a first shaft element 1822. The first pinning feature 1824 is an example where two asymmetric cuts may be used to pin the liquid metal in the gap 1816. For example, the first shaft element 1822 may be created by an asymmetric cut on the first surface 1826, while the first sleeve element 1820 may not have such a cut. In one example, the asymmetric cut on the first surface 1826 may form an acute angle (e.g., a 45° angle).

[0112] Alternatively, the pinning feature can be implemented by creating undercuts on the surfaces. For example, the second pinning feature 1834 includes a second sleeve element 1830 and a second shaft element 1832. The second sleeve element 1830 can be created by an undercut on the second surface 1836, and the second shaft element 1832 can be created by a matching, symmetrical undercut on the third surface 1838. In one example, the undercut on the second surface 1836 can form an acute angle (e.g., a 45° angle), and the undercut on the third surface 1838 can be symmetrically oriented to form a similar acute angle.

[0113] Some examples of the disclosed liquid metal bearing assemblies may include more than one filling port, more than one liquid metal reservoir, and / or more than one pinning feature. For example, there may be multiple filling ports located at different axial and radial positions. Similarly, in some examples, the assembly may include more than one pinning feature. In some examples, the disclosed liquid metal bearing assemblies may include one or more filling ports, one or more pinning features, and one or more liquid metal reservoirs. For example, there may be a first liquid metal reservoir located at a first end of the bearing, an associated first filling port, and an associated first pinning feature. At the second end of the bearing at a different axial position, there may be a second liquid metal reservoir, an associated second filling port, and an associated second pinning feature. In some examples, the first pinning feature may be shaped differently from the second pinning feature, and in other examples, they may be shaped similarly. For example, the first pinning feature may be similar to the reference Figure 8 The pinning feature described, and the second pinning feature may be similar to reference Fig.18 The first pinning feature or the second pinning feature described.

[0114] In this way, the disclosed liquid metal bearing assembly addresses current challenges associated with liquid metal bearing manufacturing by promoting good capillary wetting and liquid metal retention. The geometry of the disclosed liquid metal bearing assembly reduces the difficulty of alignment, enabling self-alignment during the assembly process, thereby improving yield and reducing capacity constraints during manufacturing. By reducing the difficulty of alignment, the disclosed liquid metal bearing assembly can reduce reliance on lubricants used during assembly, which in some examples may contaminate the liquid metal and interfere with the lubricating ability of the liquid metal. In addition, the disclosed liquid metal bearing assembly promotes complete wetting of the liquid metal and reduces the amount of liquid metal that may undesirably flow into the bearing outside the journal surface by strategically applying capillary forces. The technical effect of using a liquid metal reservoir in a liquid metal bearing is to allow a precise amount of liquid metal to be delivered to the bearing interface and to reduce the amount of gas in the bearing interface.

[0115] The present disclosure also provides support for a liquid metal bearing, the liquid metal bearing comprising: a channel that connects a liquid metal reservoir fluid to a gap between a sleeve and a shaft, the channel having a first section inclined at a first angle and a second section inclined at a second angle, wherein the first angle is different from the second angle. In a first example of the system, the first section has a first length and the second section has a second length different from the first length. In a second example of the system, optionally including the first example, the liquid metal reservoir has a first volume, and the gap has a second volume greater than or equal to the first volume. In a third example of the system, optionally including one or both of the first and second examples, the system further comprises: a filling port having a first end leading to the liquid metal reservoir and a second end including a plug. In a fourth example of the system, optionally including one or more or each of the first to third examples, a first region of the sleeve radially surrounded by the inner surface of the shaft has a first surface finish, and a second region of the sleeve not radially surrounded by the inner surface of the shaft has a second surface finish different from the first surface finish. In a fifth example of the system, optionally including one or more or each of the first to fourth examples, the system further includes: a pinning feature at an interface between a flange of the shaft and a complementary segment of the sleeve, wherein the pinning feature separates the gap from an expansion chamber formed between the sleeve and the shaft. In a sixth example of the system, optionally including one or more or each of the first to fifth examples, the system further includes: a curved transition segment between the first segment and the second segment. In a seventh example of the system, optionally including one or more or each of the first to sixth examples, the gap has a third angle different from the first angle and the second angle. In an eighth example of the system, optionally including one or more or each of the first to seventh examples, the system further comprises: a wetting reservoir connected to the liquid metal reservoir through the gap fluid, wherein the wetting reservoir is separated from the expansion chamber fluid by a pinning feature.

[0116] The present disclosure also provides support for an x-ray imaging system, the x-ray imaging system comprising: a collector assembly, a cathode assembly, and an anode assembly, the anode assembly comprising an anode supported for rotation by a bearing assembly, the bearing assembly being formed by a rotating member and a fixed member located therein, the bearing assembly also comprising a channel for fluidly coupling a liquid metal reservoir to a gap between the rotating member and the fixed member and a feature extending annularly from the fixed member to separate the gap from the gas reservoir. In a first example of the system, the fixed member is a shaft. In a second example of the system, optionally including a first example, the channel comprises a first section inclined at a first angle, a second section inclined at a second angle, and a curved transition section between the first section and the second section, wherein the first angle is different from the second angle.

[0117] The present disclosure also provides support for a method of assembling a bearing, the method comprising: inserting a shaft into a sleeve so that a first reservoir is formed at a first end of the bearing between the shaft and the sleeve, a second reservoir is formed at a second end of the bearing between the shaft and the sleeve, and a gap is formed between the first reservoir and the second reservoir, wherein the gap is separated from the second reservoir by a pinning feature; inserting a lubricant into the first reservoir via a fill port; and using capillary forces to flow the lubricant from the first reservoir into the gap. In a first example of the method, the flow includes heating the shaft and the sleeve to cause the lubricant to flow from the first reservoir into the gap. In a second example of the method, optionally including the first example, the lubricant is a first volume of gallium, and the first volume of gallium is pulled into the gap from the first reservoir by capillary forces. In a third example of the method, optionally including one or both of the first and second examples, the first volume of gallium is less than or equal to the volume of the first reservoir. In a fourth example of the method, optionally including one or more or each of the first to third examples, the method further includes: grinding the surface of the shaft and the inner surface of the sleeve so that the first reservoir and the gap have a first surface finish, and the second reservoir has a second surface finish different from the first surface finish. In a fifth example of the method, optionally including one or more or each of the first to fourth examples, the method further includes: wetting or anti-wetting the surface of the shaft and the inner surface of the sleeve. In a sixth example of the method, optionally including one or more or each of the first to fifth examples, inserting the shaft into the sleeve includes sliding the shaft from an opening at a first end of the sleeve into the sleeve, wherein the shaft and the sleeve include an aligned matching angle for easy assembly. In a seventh example of the method, optionally including one or more or each of the first to sixth examples, the filling port and the first reservoir are arranged on the sealing side of the bearing, and the pinning feature is arranged on the opposite end of the bearing between the shaft and the sleeve.

[0118] When introducing the elements of various embodiments of the present disclosure, the articles "one", "a kind of" and "the" are intended to mean that there are one or more such elements. The terms "first", "second", etc. do not represent any order, amount or importance, but are used to distinguish one element from another element. The terms "include", "comprise", and "have" are intended to be inclusive, and mean that there may be additional elements in addition to the listed elements. As used herein, the terms "connected to", "coupled to", etc., an object (e.g., material, element, structure, member, etc.) may be connected to or coupled to another object, regardless of whether the one object is directly connected or coupled to another object, or whether there are one or more intervening objects between the one object and another object. In addition, it should be understood that the reference to "an embodiment" or "embodiment" of the present disclosure is not intended to be interpreted as excluding the existence of additional embodiments that are also combined with the cited features. As described herein, unless otherwise indicated, "approximately" and "substantially" refer to values ​​within plus or minus five percent.

[0119] In addition to any previously indicated modifications, those skilled in the art may devise numerous other variations and alternative arrangements without departing from the spirit and scope of the present specification, and the appended claims are intended to cover such modifications and arrangements. Therefore, although the above has been described in detail and in detail in conjunction with what are currently considered to be the most practical and preferred aspects, it will be apparent to those of ordinary skill in the art that many modifications, including but not limited to form, function, mode of operation, and use, may be made without departing from the principles and concepts set forth herein. Likewise, as used herein, the examples and embodiments are intended to be illustrative in all respects only and should not be construed as limiting in any way.

Claims

1. A liquid metal bearing (300), comprising: a passage (314) fluidly coupling the liquid metal reservoir (312) to a gap (316) between the sleeve (302) and the shaft (304); The channel has a first section (314a) inclined at a first angle and a second section (314b) inclined at a second angle, wherein the first angle is different from the second angle.

2. The liquid metal bearing according to claim 1, wherein the first section (314a) has a first length, and the second section (314b) has a second length different from the first length.

3. The liquid metal bearing of claim 1, wherein the liquid metal reservoir (312) has a first volume, and the gap (316) has a second volume greater than or equal to the first volume.

4. The liquid metal bearing according to claim 1, further comprising a filling port (310) having a first end leading to the liquid metal reservoir (312) and a second end including a plug.

5. The liquid metal bearing according to claim 1, wherein a first area of ​​the sleeve (302) radially surrounded by the inner surface of the shaft (304) has a first surface finish, and a second area of ​​the sleeve (302) not radially surrounded by the inner surface of the shaft (304) has a second surface finish different from the first surface finish.

6. The liquid metal bearing according to claim 1 further includes a pinning feature (338) at the interface between the flange (304b) of the shaft (304) and the complementary section of the sleeve (302), wherein the pinning feature separates the gap from an expansion chamber (342) formed between the sleeve and the shaft.

7. The liquid metal bearing of claim 1, further comprising a curved transition section (458) between the first section and the second section.

8. The liquid metal bearing according to claim 1, wherein the gap (316) has a third angle different from the first angle and the second angle.

9. The liquid metal bearing of claim 1, further comprising a wetted reservoir (330) fluidly coupled to the liquid metal reservoir (312) through the gap (316), wherein the wetted reservoir is fluidly separated from the expansion chamber by a pinning feature.

10. A method for assembling a bearing, comprising: inserting a shaft into a sleeve (1304) such that a first reservoir is formed at a first end of the bearing between the shaft and the sleeve, a second reservoir is formed at a second end of the bearing between the shaft and the sleeve, and a gap is formed between the first reservoir and the second reservoir, wherein the gap is separated from the second reservoir by a pinning feature; inserting lubricant into the first reservoir via a fill port (1306); and The lubricant is caused to flow from the first reservoir into the gap using capillary forces (1308).

11. The method of claim 10, wherein the flowing includes heating the shaft and the sleeve to cause the lubricant to flow from the first reservoir into the gap (1308).

12. The method of claim 10, wherein the lubricant is a first volume of gallium, and the first volume of gallium is drawn into the gap from the first reservoir by capillary forces (1306).

13. The method of claim 12, wherein the first volume of gallium is less than or equal to the volume of the first reservoir (1306).

14. The method of claim 10, further comprising grinding a surface of the shaft and an inner surface of the sleeve so that the first reservoir and the gap have a first surface finish (1004) and the second reservoir has a second surface finish (1008) different from the first surface finish.

15. The method of claim 10, further comprising wetting or anti-wetting a surface of the shaft and an inner surface of the sleeve.

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