X-ray tube housing with integral heat exchanger

Abstract

The invention is entitled "X-ray tube housing with integral heat exchanger". The invention provides an x-ray tube housing including an outer shell having a heat exchanger integrally formed thereon in an additive manufacturing process. The additive manufacturing process allows for tight tolerances regarding the structure of the housing and the internal passages of the heat exchanger to significantly reduce the size and weight of the housing. The housing also includes a fluid distribution manifold that effectively distributes a cooling fluid within the housing to more effectively provide cooling to an x-ray tube insert disposed within the housing.

Description

[0001] Technical Field and Background Art

[0002] The present invention relates generally to x-ray tubes, and more particularly to housings for enclosing various components of x-ray tubes.

[0003] An x-ray system may include an x-ray tube, a detector, and a support structure for the x-ray tube and the detector. In operation, an imaging table on which an object is located may be located between the x-ray tube and the detector. The x-ray tube typically emits radiation, such as x-rays, toward the object. The radiation passes through the object on the imaging table and impinges on the detector. As the radiation passes through the object, the internal structure of the object causes spatial differences in the radiation received at the detector. The detector then transmits the received data, and the system converts the radiation differences into an image that can be used to evaluate the internal structure of the object. The object may include, but is not limited to, patients and inanimate objects in medical imaging procedures, such as packages in an x-ray scanner or a computed tomography (CT) package scanner.

[0004] An X-ray tube includes an X-ray tube insert and an X-ray tube housing. The X-ray tube insert is the functional device that generates X-rays, while the X-ray tube housing is the outer shell that surrounds, protects, and supports the insert. The X-ray tube housing performs the following functions:

[0005] - physically supporting the x-ray tube insert within the x-ray tube housing such that an x-ray transmission window on the x-ray tube insert is maintained in a position aligned with an x-ray transmission window in the x-ray tube housing such that x-rays generated in the x-ray tube insert exit the x-ray tube assembly and illuminate an object of interest;

[0006] - shielding x-rays emitted from the x-ray tube insert except for a defined portion that passes through one or more x-ray transmission windows toward the object of interest;

[0007] - supporting a motor stator relative to a motor rotor for use with a rotating anode x-ray tube;

[0008] - providing a high voltage electrical connection between the x-ray tube insert and the high voltage generator, typically via a high voltage plug and socket or via a high voltage connector that is removably secured to a high voltage insulator by a silicone gasket;

[0009] - Sealingly enclosing and directing coolant within the x-ray tube housing around the x-ray tube insert - the vacuum vessel of the x-ray tube insert can become hot during operation, and removing this heat by circulating dielectric oil or other suitable coolant over the x-ray tube insert vacuum vessel, which is then pumped to an external heat exchanger where it is rejected back to room air or another liquid coolant and then back to the x-ray tube housing; and

[0010] -Operably connecting the x-ray tube insert to the imaging system gantry or positioner.

[0011] See also Figure 1 and Figure 2 , an x-ray tube insert 14' is disposed within a conventional x-ray tube housing 10'. The housing 10' includes an outer shell 12', an end cap 15' secured to the outer shell 12' at one end, and a cover plate 16' secured to the outer shell 12' opposite the end cap 15'. The outer shell 12' is formed by an intermediate shell 18' in which the x-ray tube insert 14' is disposed. The outer shell 12' also includes an end shell 21' connected to one end of the intermediate shell 18', which encloses the shaft and bearing assembly 14' of the x-ray source.

[0012] The housing 12', such as the intermediate housing 18' and the end housing 21', is typically made by casting techniques, machined from bulk material, or made from separately formed parts joined together by welding and / or brazing processes. Subsequently, the intermediate housing 18' and the end housing 21' are joined to each other to enclose the x-ray tube insert 14' positioned therein.

[0013] See now Figure 1 and Figure 2 , the x-ray tube housing 10' includes a heat exchanger 24' as part of a cooling circuit 25' that utilizes a cooling system disposed external to the housing 12' and includes a water chiller / reservoir 27' and a pump 29' that circulates cooling water through a dedicated oil-to-water heat exchanger 24' to thermally contact and cool dielectric tube oil 26' contained within the housing 10' and pumped through the opposite side of the heat exchanger 24'. The oil 26' passes through an oil filter 28' that retains the electrical insulating properties of the dielectric oil 26'. As Figure 2 Schematically shown, oil 26' is present within the housing 10' to support the x-ray tube insert 14' within the housing 10' and to provide for the removal of heat from the insert 14'.

[0014] While adequate to cool the oil 26' from within the housing 10', the dedicated oil-to-water heat exchanger 24' and associated cooling circuit 25' including tubes or lines directing various fluids between the outer shell 12' and the heat exchanger 24' introduces added cost, weight, and size to the x-ray tube housing 10'. Furthermore, the size of the tube housing 10' including the heat exchanger 24' / cooling circuit 25' connected to and / or mounted to the exterior of the housing 10' significantly increases the overall size and weight of the housing 10', which limits the degree of oblique imaging angles about the patient that can be utilized and can compromise the quality of the examination performed.

[0015] An attempt to overcome the problems associated with the external heat exchange loop 25 is disclosed in co-pending and co-owned U.S. Patent Application Publication No. US2018 / 0376574, entitled X-Ray Tube Casing, which is expressly incorporated herein by reference in its entirety. In this reference, an x-ray tube casing is formed in an additively manufactured manner that forms a fluid passage directly within the casing for counterflow of dielectric oil and cooling fluid to provide heat exchange between the fluids to cool the x-ray tube insert.

[0016] However, because the disclosed x-ray tube housing still employs multiple heat exchange circuit components outside the housing and has other problems, it is desirable to develop a structure, method of manufacturing, and method of using an improved x-ray tube housing designed to reduce the weight of the housing while increasing the cooling capability of the housing when in use. Summary of the invention

[0017] In the present invention, an x-ray tube housing provides x-ray insert cooling and mechanical support without a separate external cooling circuit. The housing is formed of metal in a suitable additive manufacturing process. The housing is formed to include a wall with an integral internal passage therein to supply cooling fluid directly to and through the housing body without the need for an external cooling circuit and / or a separate component heat exchanger.

[0018] According to one aspect of an exemplary embodiment of the present invention, an x-ray tube housing is made using a metal material to form a structural wall of the housing that is continuous throughout the housing structure. This integral nature of the material forming the housing eliminates leakage that typically occurs at the joints between the component parts of the prior art housing where the individual parts are joined or secured to each other. The wall thickness of the housing can be varied during manufacturing depending on the structural strength required at any particular location. This optimization provides the necessary amount of material at different locations in the housing while minimizing the overall mass of the housing.

[0019] According to another aspect of an exemplary embodiment of the present invention, the configuration of the housing having cooling passages embedded within the housing provides the housing with the ability to direct a chilled coolant through the housing and provide more efficient heat exchange due to the large surface area of ​​the housing being in direct thermal contact with the dielectric oil flowing between the insert and the housing.

[0020] According to yet another aspect of an exemplary embodiment of the present invention, the ability to manufacture the housing with tight tolerances enables the housing to be formed to closely conform to the shape of the x-ray tube insert. This enables the size of the oil gap between the housing and the x-ray tube insert to be reduced, which thereby enhances the contact of the oil with the insert for heat transfer purposes and also provides improved dimensional stability to the insert when placed within the housing.

[0021] According to yet another aspect of an exemplary embodiment of the present invention, the housing includes a manifold disposed within the housing. The manifold provides more efficient and uniform distribution of dielectric oil within the housing surrounding an x-ray tube insert, thereby providing more efficient cooling of the x-ray tube insert. Cooling efficiency is improved by directing the overall flow of available coolant to preferential points on the insert for cooling. Due to the complexity of internal coolant routing, conventional x-ray tube housings do not include deliberate cooling flow diversion and directing.

[0022] According to yet another aspect of an exemplary embodiment of the present invention, the housing includes a component for accommodating volume expansion of the oil during operation of the x-ray tube insert. The component is formed as a deformable bladder or bellows that is located within the housing and is movable under pressure exerted by the expansion of the oil within the housing when heated. The bladder is used to maintain a desired pressure exerted by the dielectric oil within the housing by increasing or decreasing the volume inside the housing to accommodate pressure changes caused by temperature changes of the dielectric oil in the housing.

[0023] In another exemplary embodiment of the invention, the invention is an x-ray tube housing for an x-ray tube insert, the housing comprising an outer shell adapted to house at least a portion of the x-ray tube insert therein, and a heat exchanger comprising a plurality of fluid flow passages formed on an outer surface of the outer shell, wherein the outer shell and the heat exchanger are formed in an additive manufacturing process.

[0024] In yet another exemplary embodiment of the present invention, an x-ray tube includes: an x-ray tube insert including a frame defining an enclosure; a cathode assembly disposed in the enclosure; an anode assembly disposed in the enclosure and spaced apart from the cathode assembly; and an x-ray tube housing including an outer shell formed in an additive manufacturing process and in which the x-ray tube insert is positioned, the outer shell including side walls and a heat exchanger formed on an exterior of the side walls.

[0025] In an exemplary embodiment of the method of the present invention, a method for exchanging heat from a cooling fluid disposed within an x-ray tube includes the steps of: additively manufacturing an x-ray tube housing, the x-ray tube housing including an outer shell having a heat exchanger formed on an outer surface of a side wall of the outer shell, the heat exchanger including at least one passage communicating with an interior space defined by the outer shell; placing an x-ray tube insert in the interior space defined by a central frame; placing a quantity of cooling fluid in the interior space between the x-ray tube insert and the outer shell; and directing a flow of the cooling fluid through the at least one passage to exchange heat from the cooling fluid.

[0026] It should be understood that the above brief description is provided to introduce in a simplified form selected concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is solely defined by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is an isometric view of a prior art x-ray tube housing.

[0028] Figure 2 for Figure 1 Schematic diagram of a prior art x-ray housing.

[0029] Figure 3 is an isometric view of an x-ray tube housing according to an exemplary embodiment of the present invention.

[0030] Figure 4 is an isometric view of an x-ray tube end housing according to an exemplary embodiment of the present invention.

[0031] Figure 5 for Figure 3 Schematic diagram of the x-ray tube and x-ray housing.

[0032] Figure 6 for Figure 4 A partially broken away isometric view of an x-ray tube end housing.

[0033] Figure 7 for Figure 4 A partially broken away isometric view of an x-ray tube end housing.

[0034] Figure 8 for Figure 4 A partially broken away cross-sectional view of an x-ray tube end housing.

[0035] Fig. 9 For along Figure 4 A cross-sectional view taken along line 9-9.

[0036] Fig.10 for Fig. 9 A partially broken away cross-sectional view of an x-ray housing.

[0037] Fig.11 is an isometric view of an x-ray tube housing according to another exemplary embodiment of the present invention.

[0038] Fig.12 for Fig.11 A top plan view of the x-ray tube housing. DETAILED DESCRIPTION

[0039] In the following detailed description, reference is made to the accompanying drawings which form a part thereof and in which specific embodiments that can be practiced are shown by way of illustration. These embodiments are described in sufficient detail to enable those skilled in the art to practice the embodiments, and it is understood that other embodiments may be utilized and that logical, mechanical, electrical and other changes may be made without departing from the scope of the embodiments. Therefore, the following detailed description should not be considered in a limiting sense.

[0040] See now Figure 3 and Figure 4 In the exemplary embodiment shown, an x-ray tube insert (not shown) is disposed within an x-ray tube housing 100 to form the x-ray tube 11. The housing 100 includes a hollow outer shell or body 102, a high voltage (HV) connector / end cap 104 secured to the housing 102 adjacent to a cathode assembly (not shown), and a cover plate 106 ( Fig.10 ). The hollow housing 102 is formed by a generally cylindrical intermediate housing 108 which is open at each end 107, 109 and in which the cathode assembly and anode (not shown) of the x-ray tube 11 are disposed. The housing 102 also includes a generally cylindrical end housing 110 which is mounted to and / or disposed about one open end 109 of the intermediate housing 108, the intermediate housing itself including an open port 111 opposite the intermediate housing 108 and enclosing the shaft 61 and bearing assembly 63 (not shown) of the x-ray source (not shown) extending outwardly from the intermediate housing 108. Fig. 9 ).

[0041] Reference now Figure 3 to Figure 4 In the exemplary embodiment shown in FIG. 1 , the end housing 110 additionally encloses a stator basket (not shown) disposed inside the end housing 110 around the shaft 61 and the bearing assembly 63. The stator basket is operably connected to a voltage source (not shown) via a suitable connector (not shown) that extends through an aperture 116 in the end housing 110 to supply current to the stator basket to enable the basket to interact with and rotate the shaft 61 during operation of the x-ray tube insert.

[0042] See now Figures 9 and 10In the exemplary embodiment shown in FIG. 1 , the open end 111 of the end housing 110 is enclosed by the cover plate 106, which is engaged with a flexible bladder or fluid expansion bellows 117, which is located between the cover plate 106 and the open end 111 of the end housing 110. The bellows 117 is formed of a suitable material, such as a rubber bladder, and extends over the entire open end 111 of the end housing 110. In the exemplary embodiment shown, the bellows 117 is generally circular in shape and includes a curved cross-section to provide the bellows 117 with the ability to expand and contract under a pressure differential applied to the bellows 117. In order to maintain a fluid-tight seal with the cover plate 106 and the end housing 110, the bellows 117 includes a peripheral cylindrical bead 118 formed around the entire periphery of the bellows 117. The beads 118 are disposed within and compressed by aligned complementary grooves 120, 122 formed in the cover plate 106 and the end housing 110, respectively, to provide a fluid-tight seal while also allowing the bellows 117 to expand and contract between the cover plate 106 and the end housing 110. To accommodate expansion and contraction, the cover plate 106 includes vents 124 that allow air to enter and exit a space 126 defined between the bellows 117 and the cover plate 106.

[0043] As opposed to the cover plate 106, the end housing 110 is secured to the intermediate housing 108 in a suitable manner to seal the end housing 110 to the intermediate housing 108. With the end housing 110 so sealed, it is possible to fill the end housing 110 with a quantity of dielectric oil 136, such as via a sealable oil fill port 139, to provide cooling for the operation of the shaft 61 and the bearing assembly 63.

[0044] like Figure 5 1, when assembled with the HV connector / end cap 104 and the cover plate 106, the housing 102 defines an interior space (not shown) in which portions of the x-ray tube insert including the cathode assembly and the anode / target 56 are located. The intermediate housing 108 and the end housings 110 of the housing 102 effectively form a fluid-tight enclosure around the interior space 134 to retain a volume of cooling fluid / dielectric oil 136 in the interior space 134 between the x-ray tube insert / source 14 and the housing 102. The oil 136 is introduced through a sealable fill port 139 formed in the end housing 110 and is used to flow through and thermally contact the frame 50 surrounding the x-ray tube / source 14 and to draw heat generated by the operation of the x-ray tube insert 14 out of the x-ray tube insert 14 through contact with the frame 50, cooling the internal components of the x-ray tube insert 14.

[0045] Reference now Figures 4 to 8In order to remove heat from the insert cooling fluid / dielectric oil 136, the housing 100 or one or more components of the housing 100, such as the entire housing 102, the intermediate housing 108, the end housing 110, the end cover 104, or any combination thereof, can be formed to include one or more passages 138 or channels 152, 154 therein to enable the cooling fluid 140 to pass through the sidewall 121 of the housing 100 or its components. This provides an overall cooling function for the housing 100 so that the housing 100 can effectively remove the heat generated by the operation of the shaft 61 and the bearing assembly 63.

[0046] exist Figure 5 In one exemplary embodiment schematically shown in FIG. 1 , one or more passages 138 may be formed as a continuous passage 138 extending through the sidewall 121 of the housing 102 or a portion thereof, or may be formed as separate passages 138, each extending through the sidewall 121. The one or more passages 138 are each connected to a source of cooling fluid 140, such as water, a water / ethylene glycol mixture, or any other suitable fluid having the desired heat exchange characteristics, which is directed into the passages 138 to flow from the inlet water header 142, 157 to the outlet water header 144, 159 of each passage 138. The heat transfer characteristics of water are significantly better than those of dielectric oil, so the overall heat transfer depends on the heat transfer from the vacuum vessel wall / frame 50 to the oil 136. Each passage 138 is formed in the side wall 121 to maintain a thickness of the side wall 121 between the interior space 134 of the housing 102 and the passage 138 that is sufficient to allow the cooling fluid 140 flowing through the passage 138 to be in thermal contact with the oil 136 located within the interior space 134, but not to allow the oil 136 and the fluid 140 to be in direct contact with each other. This provides efficient heat exchange due to the large surface area of ​​the side wall 121 being in direct contact with the dielectric oil 136 flowing in the space or gap 180 between the x-ray tube insert 14 and the side wall 121. The cooling fluid 140 can be introduced into the inlet end 142 of the passage 138 by a pump 146 connected to a refrigerated reservoir 148 of the cooling fluid 140, which is used to cool the heated cooling fluid 140 exiting the passage 138 in the housing 102. Operation of the pump 146 may be controlled to direct the cooling fluid 140 into the passage 138 at a rate commensurate with the operation of the x-ray tube 14 in order to provide appropriate cooling to the dielectric oil 136 .

[0047] The dielectric oil 136 may be brought into thermal contact with the cooling fluid 140 in the one or more passages 138 by convection alone, in which case the heat absorbed by the oil 136 adjacent the frame 50 causes the heated oil 136 to move outward from the frame 50, where it is heated through the interior space 134 toward the housing 102. Upon reaching the housing 102, the heated oil 136 is brought into thermal contact with the cooling fluid 140 flowing through the one or more passages 138 to cool the oil 136, which then flows back to the frame 50 to move the heated oil 136 adjacent the frame 50. This embodiment is suitable for lower average power x-ray tubes 14 employed on surgical C-arms, and further reduces cost, size, and weight by eliminating the oil pump 150.

[0048] Alternatively, the oil 136 may be circulated into thermal contact with the cooling fluid 140 by a pump 150 that draws the heated oil 136 from the interior space 134 via a suitable conduit connected to an outlet header 153 and through an oil filter 149, and then reintroduces the oil 136 from the filter 149 via a suitable conduit through an inlet header 155 into the interior space 134 of the housing 102. In this way, the oil 136 is brought into thermal contact with the cooling fluid 140 flowing through one or more passages 138 so as to cool the oil 136.

[0049] Especially with respect to Figure 4 and Figures 6 to 8 In the exemplary embodiment shown in FIG. 1 , the housing 100 or a component of the housing 100, such as the entire shell 102, the intermediate housing, the end housing 110, or any combination thereof, can be formed with internal counter-flow channels 152, 154 separated by plates 151 and extending through the side wall 121 of the end housing 110 / the component of the housing 100 in place of the passage 138. As shown with respect to the end housing 110, the channels 152, 154 and the plates 151 are located within an integral heat exchanger 160 that is directly on the exterior of the side wall 121 of the end housing 110 and is integrally formed therewith.

[0050] like Figure 6 and Figure 7 In the exemplary embodiment shown, within the heat exchanger 160, a passage 152 is connected between an oil inlet header 153 and an oil outlet header 155 for providing a first flow path 156 for the heated dielectric oil 136. The oil 136 is pumped from the outlet header 155 via a suitable conduit connected to a pump 150, which can be disposed directly in a pump chamber or housing 170 on the end housing 110 ( Figure 11 to Figure 12), which is used to extract the heated oil 136 from the interior 134 of the end housing 110. In addition, the end housing 110 / heat exchanger 160 can be formed to additionally integrally connect the oil outlet header 155 with the manifold 164 to guide the cooled oil 136 back to the interior 134 of the housing 100. Fig.11 and Fig.12 In the exemplary embodiment shown, the housing 170 is integrally formed with the remainder of the end housing 110, such as in an additive manufacturing process, and includes the oil inlet and outlet ports formed therein. In this way, the oil inlet 153 and the oil outlet 155 are eliminated from the end housing 110, thereby further reducing the number of hoses and other connections required for the operation of the tube 11.

[0051] In addition, if Fig.12 As shown in the exemplary embodiment shown, passage 154 is connected between oil inlet header 157 and water outlet header 159 to provide a second reverse flow path 158 for cooling fluid / water 140, which is directed from reservoir 148 to and from passage 154 via suitable conduits connected to pump 146. While any configuration of passages 152, 154 is considered within the scope of the present invention, Figure 8 As shown in the exemplary embodiment of FIG. 1 , one or both of the channels 152, 154 may be formed as a plurality of conduits 161 separated by fins 162 to increase the thermal contact and the subsequent heat transfer between the oil 136 and the cooling fluid 140 flowing through the channels 152, 154. The channels 152, 154 may also be formed with a certain angle slope to provide additional structural integrity to the channels 152, 154. In addition, the number of conduits 161 formed in the corresponding channels 152 and channels 154 may be formed to be the same or different from each other to achieve the desired heat exchange within the heat exchanger 160 including the channels 152, 154.

[0052] Reference now Fig. 9 and Fig.10In the exemplary illustrated embodiment, the cooled dielectric oil 136 from the oil outlet manifold 155 is introduced into a fluid distribution manifold 164 disposed within the end housing 110 adjacent the bellows 117 and, in the exemplary embodiment illustrated, integrally formed with the end housing 110. The manifold 164 extends within the interior of the end housing 110 and includes a plurality of spaced-apart nozzles or holes 166, 168 extending therethrough. The holes 166 are located at the periphery of the manifold 164 and are used to direct a quantity of the cooled dielectric oil 136 into the interior 134 of the end housing 110 where the oil 136 can be in thermal contact with the frame 50 of the x-ray tube insert 14. The holes 168 are generally centrally disposed on the manifold 164 in alignment with the bearing assembly 63 so as to direct a quantity of the cooled dielectric oil 136 into the shaft 61 and the bearing assembly 63.

[0053] Because the passages 138 or channels 152, 154 are formed directly within the sidewall 121 of the housing 100, a manufacturing process with tight tolerance control is required to form the housing 100. In order to reduce cost, reduce weight, and provide the complex formed sidewall 121 with internal passages 138 or channels 152, 154 as described above, the housing 100 / housing 102 / intermediate housing 108 / end housing 110 can be manufactured or formed at least partially or entirely via one or more additive manufacturing techniques or processes, thereby providing greater accuracy and / or more complex details within the housing 100 / housing 102 / intermediate housing 108 / end housing 110 than previously producible via conventional manufacturing processes. As used herein, the term "additive manufacturing" or "additive manufacturing techniques or processes" includes, but is not limited to, various known 3D printing manufacturing methods such as extrusion deposition, wire, granular material bonding, powder bed and inkjet 3D printing, lamination, and photopolymerization.

[0054] In one embodiment, the additive manufacturing process of direct metal laser melting (DMLM) is an exemplary method of manufacturing the housing 100 / shell 102 / intermediate housing 108 / end housing 110 or its components described herein. DMLM is a known manufacturing process that uses three-dimensional information to manufacture metal components, such as a three-dimensional computer model of the housing 100 / shell 102 / intermediate housing 108 / end housing 110. The three-dimensional information is converted into a plurality of slices, where each slice defines a cross-section of the component for a predetermined height of the slice. The housing 100 / shell 102 / intermediate housing 108 / end housing 110 (such as the sidewall 121 of the end housing 110) is then "built up" piece by piece or layer by layer until it is completed. Each layer of the housing 100 / shell 102 / intermediate housing 108 / end housing 110 is formed by melting or fusing layers of metal powder (such as aluminum powder) or other materials / metals (such as stainless steel) to each other using a laser.

[0055] Although the method of manufacturing the housing 100 / shell 102 / intermediate housing 108 / end housing 110 including the internal passage 138 or channels 152, 154 has been described herein using DMLM, those skilled in the art of manufacturing will recognize that any other suitable rapid manufacturing method using layer-by-layer construction or additive manufacturing may also be used. These alternative rapid manufacturing methods include, but are not limited to, direct metal laser sintering (DMLS), selective laser sintering (SLS), 3D printing (such as by inkjet and laser inkjet), stereolithography (SLS), direct selective laser sintering (DSLS), electron beam sintering (EBS), electron beam melting (EBM), laser engineered net shaping (LENS), laser net shaping manufacturing (LNSM) electron beam powder bed fusion and direct metal deposition (DMD).

[0056] Due to the precise manufacturing tolerances provided by using an additive manufacturing process to manufacture the housing 100, the width and / or height of the passages 138 or channels 152, 154 within the heat exchanger 160 can be formed to be between 1.0 mm and 2.0 mm, and in other embodiments between 1.4 mm and 1.8 mm. In addition, precise control of the overall shape of the housing 100, including the intermediate housing 108 and the end housing 110, relative to the shape of the x-ray tube insert 14, allows for a reduction in the size of the oil gap 180 between the frame 50 of the x-ray tube insert 14 and the sidewall 121 of the housing 100, thereby significantly increasing the heat transfer coefficient compared to conventional x-ray housings by maintaining a smaller hydraulic diameter of the oil layer / gap 160.

[0057] Furthermore, while the additive manufacturing processes used to construct the housing 100 (e.g., the end housing 110) allow for precise manufacturing tolerances, the nature of the one or more materials used in these processes results in relatively rough or uneven surfaces of the end housing 110. Thus, these uneven or rough surfaces within the passages 138 or channels 152, 154 further enhance the heat exchange characteristics of the heat exchanger 160 including the passages 138 or channels 152, 154 due to the increased surface area within the passages 138 or channels 152, 154 from the rough surfaces.

[0058] Incorporating the heat exchanger 160 directly into the end housing 110 through additive manufacturing processes of the housing 100 and / or its component parts (such as the entire outer shell 102, the intermediate housing 108, and / or the end housing 110 in particular) allows for a significant reduction in the size and weight of the x-ray tube 12, including the insert 14 and the housing 100. The end housing 110 structurally incorporates multiple previously external or additional components into the end housing 110 to achieve this purpose, and eliminates multiple connecting hoses, seals, and potential leak points that result. The end housing 110 also provides directional cooling to the insert 14 and bearing assembly via the manifold 164, and internally contains the expansion of the oil 136 through the use of the bellows 117, all within the structure of the end housing 110.

[0059] Due to this improved structure of the housing 100, and in certain exemplary illustrated embodiments, the end housing 110, a smaller and lighter x-ray tube 11 improves the angle of the tube 11 around the patient to improve the viewing angle and provide better treatment. In addition, the x-ray tube 11 has a smaller footprint, which allows for better access to the patient and reduces static and dynamic loads on the C-arm, thereby achieving faster rotation speeds and lower gantry costs.

[0060] This written description uses examples to disclose the invention, including the best mode, and also to enable those skilled in the art to practice the invention, including making and using any devices or systems and performing any included methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to fall within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insignificant differences from the literal language of the claims.

Claims

1. An x-ray tube housing for an x-ray tube insert, the housing comprising: - a housing adapted to receive at least a portion of the x-ray tube insert therein and including an end housing enclosing a shaft and bearing assembly of the x-ray tube insert; - a heat exchanger including a plurality of fluid flow passages formed on an outer surface of the housing, and; - a fluid distribution manifold disposed within the interior of the housing, - wherein the housing and the heat exchanger are formed in an additive manufacturing process, - wherein the fluid distribution manifold comprises a plurality of first holes located at a periphery of the fluid distribution manifold, and a second hole located centrally on the fluid distribution manifold and aligned with the bearing assembly of the x-ray tube insert, The fluid distribution manifold is configured to direct cooling dielectric oil into the interior of the end housing through the plurality of the first holes and to direct cooling dielectric oil into the shaft and the bearing assembly through the second holes.

2. The x-ray tube housing of claim 1, wherein the plurality of fluid flow passages comprises a first fluid flow passage and a second fluid flow passage.

3. The x-ray tube housing of claim 2, wherein the first fluid flow path and the second fluid flow path are counter-current to each other.

4. The x-ray tube housing of claim 2, wherein the first fluid flow passage and the second fluid flow passage have different sizes.

5. The x-ray tube housing of claim 2, wherein one of the first fluid flow path or the second fluid flow path is in fluid communication with an interior space of the outer shell.

6. The x-ray tube housing of claim 1, wherein the manifold is integrally formed with the outer shell.

7. The x-ray tube housing of claim 1, wherein the outer shell includes an oil pump chamber formed on an exterior of the outer shell.

8. The x-ray tube housing of claim 7, wherein an oil pump housing is in fluid communication with the plurality of fluid passages in the heat exchanger.

9. The x-ray tube housing of claim 1, further comprising a fluid expansion bellows disposed within the outer shell.

10. The x-ray tube of claim 9, wherein the bellows includes a peripheral sealing bead engaged with the housing.

11. The x-ray tube housing of claim 1 , wherein the outer shell comprises: - an intermediate housing in which at least a portion of the x-ray tube insert is arranged; and - the end housing, which is fixed to the intermediate housing, in which at least a part of the x-ray tube insert is arranged, the end housing including the heat exchanger having a plurality of fluid flow passages formed on an outer surface of the end housing.

12. An x-ray tube comprising: - x-ray tube insert; and - an x-ray tube housing comprising an outer shell formed in an additive manufacturing process and in which the x-ray tube insert is placed, the outer shell comprising a side wall and a heat exchanger formed on an exterior of the side wall, - the housing further comprises an end housing enclosing a shaft and a bearing assembly of the x-ray tube insert, and a fluid distribution manifold disposed within an interior of the end housing, - wherein the fluid distribution manifold comprises a plurality of first holes located at a periphery of the fluid distribution manifold, and a second hole located on the fluid distribution manifold and centrally disposed in alignment with the bearing assembly of the x-ray tube insert, The fluid distribution manifold is configured to direct cooling dielectric oil into the interior of the end housing through the plurality of the first holes and to direct cooling dielectric oil into the shaft and the bearing assembly through the second holes.

13. The x-ray tube of claim 12, wherein the heat exchanger comprises: - a first internal passage, the first internal passage having an inlet and an outlet, wherein the first internal passage is not in fluid communication with an interior space defined by the housing; and - a second internal passage having an inlet and an outlet, wherein the second internal passage is in fluid communication with the interior space defined by the housing.

14. A method for exchanging heat from a cooling fluid disposed within an x-ray tube, the method comprising the steps of: - additively manufacturing an x-ray tube housing comprising an outer shell having a heat exchanger formed on an outer surface of a side wall of the outer shell, the heat exchanger comprising at least one passage in communication with an interior space defined by the outer shell; - placing an x-ray tube insert within the interior space defined by the central frame; - placing a quantity of cooling fluid in the interior space between the x-ray tube insert and the housing; as well as - directing a flow of the cooling fluid through the at least one passage to exchange heat from the cooling fluid, - wherein the housing further comprises an end housing enclosing a shaft and a bearing assembly of the x-ray tube insert, and the fluid distribution manifold disposed within an interior of the end housing, - wherein the fluid distribution manifold comprises a plurality of first holes located at a periphery of the fluid distribution manifold, and a second hole located on the fluid distribution manifold and centrally disposed in alignment with the bearing assembly of the x-ray tube insert, The fluid distribution manifold is configured to direct cooling dielectric oil into the interior of the end housing through the plurality of the first holes and to direct cooling dielectric oil into the shaft and the bearing assembly through the second holes.

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