Vacuum tube insert assembly with feedthrough pin plug and mating socket

Abstract

The vacuum tube insert assembly includes a flared insert having an annular flange and a stem, each constructed from glass. The stem extends axially from the flange. The flange surrounds an outer periphery of a plug concavity defined by the stem. A feedthrough pin passes axially through the stem and is sealed to the stem. The pin terminates inside the concavity to form a plug. A socket connects to the plug within the concavity and includes a receptacle that removably couples to the pin, with an engagement feature preventing an incorrect plug-socket connection. The method includes axially inserting the pin through the stem in a fixed relative position such that the pin is disposed within the plug concavity, sealing the stem such that the stem is vacuum sealed to the pin, thereby forming a plug, and removably coupling a mating receptacle of the socket to the pin.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 217,019, filed June 30, 2021, which is incorporated herein by reference in its entirety. [Background technology]

[0002] Vacuum tubes are used in a wide range of applications to control the flow of electric current between separated electrodes within a sealed vacuum chamber. X-ray tubes are a specialized type of vacuum tube commonly used to generate and direct X-ray radiation for a variety of purposes, including medical imaging, radiology, diagnostics, radiography, tomography, non-destructive testing, materials analysis, security applications, and inspection.

[0003] Conventional X-ray tubes operate by using an energized cathode to emit a focused electron beam, which is then directed toward a target on which an anode is attached. The emitted electrons gain energy and accelerate due to a large potential difference across the space between the anode and cathode. Some of the accelerated electrons strike the target surface on the anode, and a small portion of the incident electron beam energy is converted into useful X-ray radiation. The remaining energy is primarily in the form of heat, which is dissipated from the X-ray tube, usually through some type of cooling system.

[0004] The drawings described herein are for illustration purposes only and are schematic in nature and are intended to be exemplary rather than limiting the scope of the present disclosure. [Brief explanation of the drawings]

[0005] [Figure 1] FIG. 1 is a diagram of an exemplary vacuum tube insert assembly for an X-ray tube, the assembly having feedthrough pins forming a plug and also having a mating socket as described herein. [Figure 2]FIG. 2 is a perspective view of one embodiment of the vacuum tube insert assembly shown in FIG. 1. [Figure 3] FIG. 2 is a schematic diagram of an exemplary dual filament device for use with the cathode assembly shown in FIG. 1. [Figure 4] FIG. 1 is a perspective view of a representative portion of a flared insert constructed as described herein. [Figure 5] FIG. 1 is a perspective view of a representative portion of a flared insert constructed as described herein. [Figure 6] FIG. 6 is a perspective view of a socket configured to connect to the plug of the flared insert shown in FIGS. 4 and 5. [Figure 7] FIG. 6 is a perspective view of a socket configured to connect to the plug of the flared insert shown in FIGS. 4 and 5. [Figure 8] 8A and 8B illustrate, in schematic form, alternative engagement features for the socket shown in FIG. 7; [Figure 9] FIG. 3 is a perspective view of a pin retainer for use during assembly of the flared insert and vacuum tube insert of FIGS. 1 and 2. [Figure 10] FIG. 3 is a perspective view of a pin retainer for use during assembly of the flared insert and vacuum tube insert of FIGS. 1 and 2. [Figure 11] 1 is a flowchart illustrating an exemplary method for constructing a vacuum tube insert according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0006] Embodiments of the present disclosure are described herein. The disclosed embodiments are provided as examples and illustrations of various solutions. The drawings are not necessarily to scale, and some features may be exaggerated or minimized to show specific details of the subject matter. Therefore, specific structural and functional details disclosed herein should not be construed as limiting, but merely as a representative basis for teaching those skilled in the art to variously employ the disclosed structures and methods.

[0007] The numbers provided in the flowcharts and process descriptions are for the purpose of improving clarity and do not necessarily indicate a particular order or sequence. For purposes of the present invention, approximation terms such as "about," "substantially," "generally," and "approximately" may be used to mean "at or near," or "within 0 to 5% of," or "within an acceptable manufacturing tolerance," respectively, or any logical combination thereof.

[0008] Some embodiments described herein relate generally to x-ray tubes and other types of vacuum tubes, glass inserts constructed for use with such vacuum tubes, and methods for making and using the vacuum tubes and glass inserts described herein. In particular, the following disclosure relates to the extension of a substantially rigid, electrically conductive feedthrough post or pin into a bowl-shaped cavity ("concave") in a defined open end of a flared insert for a glass vacuum tube, where the insert eventually melts and fuses with the glass encapsulant or envelope. The feedthrough pin is positioned to present a plug to which an operator can removably couple a mating socket. The socket configuration may vary with specific temperatures and other expected loads applied during testing, loading, and other stages of manufacturing and use.

[0009] In contrast to existing approaches in which flexible wires are separately welded to the ends of mating feedthrough wires, the rigid feedthrough pins contemplated herein are less susceptible to breakage, fraying, burning, and electrical shorting conditions due to their increased rigidity and extension into the concave volume as the plugs are spaced and oriented as desired. Furthermore, the unique plug-and-socket combination described below is much less prone to inadvertent wiring errors. Furthermore, because contemplated sockets of a particular configuration can be installed in only one specified orientation, the plug-and-socket connection reduces errors during manufacturing, installation, and maintenance.

[0010] Referring now to the drawings, wherein like numbers refer to like components, a vacuum tube insert assembly 10 includes plug means as described herein, such as representative plug 12 shown generally in FIG. 1. A mating socket means, illustrated as socket 14, is disposed at a distal end 15 of a flexible cable 16 and is removably coupled to plug 12, as shown by arrow A, for providing power to, for example, the vacuum tube insert assembly 10 or to a device assembled using the vacuum tube insert assembly 10. As understood in the art, when the vacuum tube insert assembly 10 is used as part of an x-ray tube, the vacuum tube insert assembly 10 may be positioned within a lead-lined protective alloy or machined housing (omitted for clarity) or another suitable protective outer structure to provide stable mechanical support and thermal insulation.

[0011] 1 , in a non-limiting x-ray tube embodiment, includes various components that collectively generate x-ray radiation (arrows 18) and emit it through a window 20 toward a subject 22, such as a patient's chest or appendages. Such components include glass means such as an enclosure or envelope 24 that is constructed from glass and defines an interior volume 25 in which a positively charged anode assembly 26 and a negatively charged cathode assembly 28 are positioned, as understood in the art. As described herein in various exemplary embodiments, envelope 24 is not limited to glass as a material of construction, but may be constructed from borosilicate glass or another rigid, application-appropriate glass material, and is therefore hereinafter referred to as glass envelope 24.

[0012] 1 for purposes of illustration, the anode assembly 26 includes a cylindrical, bearing-mounted rotor 30 having an axis of rotation 31. A stator 32 surrounds a neck 33 of the glass envelope 24, and the stator 32 defines the rotor 30. Thus, when the stator 32 is energized, alternating electromagnetic forces of attraction and repulsion cause the rotor 30 to rotate about the axis of rotation 31, which in turn causes rotation of an anode target disk 34, constructed, for example, from tungsten, attached to the rotor 30 via, for example, an anode stem 35. As understood in the art, the target disk 34 provides a material target for interaction with the electrons emitted by the cathode assembly 28, and ultimately, x-rays result from such interaction.

[0013] 1 includes a cathode head 36 to which a focus cup 38 is connected. The focus cup 38, in turn, includes or is connected to one or more conductive filaments 39, each of which may likewise be constructed from tungsten or another suitable material. When the cathode assembly 28 is energized, current flows through the filament(s) 39, heating them. The heated filament(s) 39 respond by emitting electrons via the process of thermionic emission.

[0014] A high voltage of about 1 kilovolt (kV) or more is typically applied between the anode assembly 26 and the cathode assembly 28. Thus, the glass envelope 24 is typically heated to 1000 K. -6 It functions as a hermetically sealed vacuum enclosure that maintains a high vacuum of less than mmHg. In addition to maintaining such a strong vacuum, the glass envelope 24 also isolates the anode assembly 26 from the cathode assembly 28 with a potential difference as high as 150 kV or more maintained between them without significant electrical leakage or spurious discharge.

[0015] The glass envelope 24 contemplated herein includes a flared insert 40 positioned adjacent to the cathode assembly 28, as shown in more detail in Figures 4 and 5. As explained in more detail below, the flared insert 40 eventually melts and thereafter fuses with and / or is integrally formed with, and thus vacuum-sealed to, feedthrough pin means, exemplified as a plurality of feedthrough pins 42 that also pass axially through the flared insert 40. The feedthrough pins 42 collectively form the plug 12 within a plug recess 44 defined by the flared insert 40. The plug 12 is therefore easily accessible for receiving power during various stages of production.

[0016] To that end, socket 14 is removably coupled to plug 12 within plug recess 44, which occurs with a correspondingly minimal level of effort. After connecting the various components of vacuum tube insert assembly 10 shown in Figures 1 and 2, flared insert 40, described below with respect to Figures 3 to 9, is connected to glass envelope 24, after which internal volume 25 is evacuated using a pump and other associated equipment.

[0017] Referring briefly to FIG. 3 , the number of feedthrough pins 42 (see FIGS. 1 and 2 ) may vary depending on the configuration of the vacuum tube insert assembly 10. In some embodiments, for example, filament(s) 39 may include multiple filaments 39, such as the dual-focus type shown having filaments 139 and 239. Filaments 139 and 239 are shown with corresponding terminals or nodes, with filament 139 having nodes 57A and 57B and filament 239 having nodes 57B and 57C. Also shown are getter 70 with getter node 57D and grid 72 with grid node 57E. The corresponding notations “S small,” “C common,” and “L large” can be used to connect a single “small” filament (e.g., filament 139 extending between nodes 57A and 57B) or a single “large” filament (e.g., filament 239 extending between nodes 57B and 57C). Filaments 139 and 239 may be connected in series by connecting nodes 57A and 57C. Filaments 139 and 239 may be connected in parallel by connecting nodes 57A, 57B, and 57C. As is understood in the art, using smaller filaments produces smaller focal spots suitable for imaging smaller areas, for example. Conversely, using multiple / larger filaments produces larger focal spots with correspondingly larger imaging areas.

[0018] In addition to nodes 57A, 57B, and 57C, feedthrough pin 42 in FIGS. 1 and 2 may also include “getter” and “grid” nodes 57D and 57E, respectively, for a total of five associated feedthrough pins 42 in this embodiment. The specific identities of nodes 57A through 57R may vary depending on the application, and thus the locations shown in the five-pin embodiment of FIG. 3 represent only one possible implementation. As used herein and in the art, a getter absorbs off-gassing particles during manufacturing and also serves to maintain a vacuum after sealing. Thus, getter node 57D provides one of the electrical connections to getter 70. A grid can be used to focus electrons or for fast switching speeds, i.e., to limit or even block the flow of electrons as the x-ray source is turned on and off. Thus, grid node 57E provides one of the electrical connections to grid 72. It is also contemplated that some of the nodes shown will be unused, i.e., tied together, e.g., grid node 57, getter node 57E, and common node 57B, which may be tied together either within the tube or external to the tube. Consequently, cable 16 of FIG. 1 may not be supplied with the same number of voltage inputs as feedthrough pins 42, e.g., in the example of a four-pin or three-pin configuration. However, for illustrative consistency, vacuum tube insert assembly 10 will be described hereinafter as a representative five-pin configuration.

[0019] 4 and 5, the flared insert 40 includes an annular flange 45, such as a substantially flat disk as shown. The annular flange 45 is integrally formed with an axially extending stem 46. The axially extending stem 46 in turn defines a plug concave surface 44 having an outer circumferential edge 47, which is shown but not labeled in FIG. 2. The plug concave surface 44 may, by way of example, have a generally hemispherical or rounded conical shape, such that the plug concave surface 44 has a concave, bowl-like appearance from the perspective of FIG. 4. The tubular flange 45 surrounds the outer circumferential edge 47 of the plug concave surface 44, and the outer diameter and thickness of the annular flange 45 correspond to the outer diameter and thickness of the remaining structure of the glass envelope 24 to which the insert will ultimately be fused or connected.

[0020] 4, the feedthrough pin 42 passes axially through the stem 46 and melts or fuses to the stem 46. The feedthrough pin 42 thus becomes integral with the surrounding glass of the stem 46 as the glass cools to provide the necessary vacuum-tight integrity between the vacuum side within the evacuated interior volume 25 of the glass envelope 24 (see FIG. 1) and the surrounding external / atmospheric pressure side of the vacuum tube insert assembly 10 shown in FIG.

[0021] The feedthrough pin 42 of FIG. 5 can include a center post 50 flanked by at least two pins 52, with four pins 52 surrounding the center post 50 in the non-limiting exemplary configuration of FIG. 5. The center post 50 can have a first radial dimension, such as a diameter, when the center post 50 is cylindrical, while each of the pins 52 can have a smaller second radial dimension. For example, the second radial dimension can be less than about 80 percent of the first radial dimension, such as about 40 to 60 percent of the first dimension, or about 25 to 75 percent of the first dimension, in various exemplary embodiments. Using a more rigid or thicker configuration for the center post 50 facilitates construction of the vacuum tube insert assembly 10 of FIGS. 1 and 2, for example, by providing a substantially rigid, central indexing feature to which other components and / or fixtures may be aligned or referenced. Although a cylindrical feedthrough pin is shown, the feedthrough pin may have a variety of cross-sections, including, but not limited to, circular, oval, rectangular, or another polygonal or other shape. Engagement features, described in more detail below, may be formed when two or more different cross-sectional shapes (or cross-sectional areas) are used on the feedthrough pin and the corresponding mating receptacle 56 of the socket 14 (FIGS. 7-8) so that the plug 12 is received by the socket 14 in a designated and / or unique orientation. Other engagement features may be formed by other variations of the features, with examples provided below, so long as the plug 12 is received by the socket 14 in a designated and / or unique orientation.

[0022] Proper fusing and bonding of the glass material of the stem 46 to the feedthrough pin 42 can be accomplished by a variety of means, one of which is the use of a press and a heat source. As understood in the art and used herein, such a press can be used to pinch / concentrate the heated glass material of the stem 46 together so that the softened, viscous glass material flows around and surrounds the feedthrough pin 42. As the glass cools, the feedthrough pin 42 becomes one with the stem 46 with no intervening gaps or spaces present at the interface between the feedthrough pin 42 and the surrounding glass.

[0023] To facilitate the necessary vacuum-sealing properties, the material used to construct the feedthrough pin 42 must have a coefficient of expansion similar to that of the glass of the glass envelope 24, so that cracks or gaps do not form as the glass cools and solidifies. One possible combination suitable for such a vacuum seal is borosilicate glass or another hard glass for the construction of the flared insert 40 and a plated or unplated metal, such as tungsten (W), molybdenum (Mo), or a nickel-cobalt alloy (Ni-Co-Fe) such as Kovar®, both of which are suitable for the construction of the feedthrough pin 42. That is, the feedthrough pin 42 may be constructed from a first metal that may optionally be plated with a second metal. When plated, a suitable conductive metal may be used to ensure continuity and reduce resistance; elemental nickel (Ni), gold (Au), copper (Cu), or silver (Ag) are some possible plating materials. The plating material may have a high thermal resistance to reduce damage due to thermal stress.

[0024] As best shown in Figure 4, the feedthrough pins 42 terminate at locations inside the plug recess 44, collectively forming the plug 12. The plug 12 is thus presented at a convenient height above the stem 46 for connecting power as needed to the vacuum tube insert assembly 10 of Figures 1 and 2, with power compositions and levels that may vary depending on the particular stage of assembly, testing, or loading. For example, the length of the feedthrough pins 42 exposed within the volume of the plug recess 44 may be at least 4 mm to about 10 mm, or another suitable length sufficient to penetrate and securely engage a mating receptacle 56 of the socket 14, as described herein.

[0025] 6, the flared insert 40 is shown as it would appear when viewed from the exterior / atmospheric pressure side of the vacuum tube insert assembly 10 of FIGS. 1 and 2. The appearance of the non-flexible / substantially rigid plug 12 (see FIG. 4) within the plug recess 44 eliminates the need to weld individual flexible wires to each of the feedthrough pins 42 when installing the cathode assembly 28 of FIG. 1, for example, which may be prone to manufacturing or operator error. Instead, the exposed feedthrough pins 42 of the plug 12 and the socket 14 may simply engage within the plug recess 44, with an annular flange 45 surrounding the outer periphery 47 of the plug recess 44.

[0026] Socket 14 terminates electrical wires 160 forming cable 16, with individual electrical contacts of the wires 160 housed within socket 14. Each of the wires 160 shown in FIG. 6 corresponds to one of the small, large, common, getter, or grid nodes described above in the exemplary five-pin embodiment of FIG. 6. For ease of assembly, socket 14 may define a respective through channel 49 for each of the wires 160, which would allow the wires 160 to pass cleanly through socket 14 and engage with mating receptacles 56 housed therein, as shown in FIG. 7. Any or all of the receptacles 56 may include resistors therein or in series therewith for current limiting, current sensing, or other beneficial purposes.

[0027] As contemplated herein, each of the receptacles 56 can be constructed in a variety of alternative shapes and with internal contact structures appropriate for the application to receive and subsequently securely retain a respective one of the feedthrough pins 42. That is, a resilient internal conductive connection or interference fit is provided between the mating feedthrough pins 42 and the receptacle 56 to ensure good electrical connection and continuity between the plug 12 and the socket 14. Alternative types of plug-socket connections, such as, but not limited to, male-female plug-socket configurations, hyperbolic contacts, or other suitable embodiments, may be used within the scope of this disclosure. While omitted for simplicity of illustration, additional retention mechanisms, such as keyways or similar structures that require partial rotation of the mated socket 14 after inserting the plug 12 to securely lock the plug 12 in place, may also be used in other embodiments.

[0028] The materials of construction of socket 14 may vary depending on the stage of manufacture. For example, stages requiring socket 14 to be exposed to higher temperatures or power levels may be constructed from high-temperature resin, while lower temperature or steady-state operation stages may use lower-temperature materials such as polycarbonate. Lower-temperature materials may be used in part because cooling oil and other thermal regulation structures are present in fully assembled vacuum tube devices, such as x-ray tubes, which similarly reduce the thermal load on socket 14. To form the desired geometry, in some embodiments, three-dimensional (3D) printing or additive manufacturing techniques may be used to construct socket 14 of FIG. 6.

[0029] Further, with respect to the socket 14, errors during installation are reduced by engagement features 60 configured to allow the plug 12 to accept the socket 14 in a specified orientation, and vice versa. As described below, the socket 14 or plug 12 can include engagement features 60, separately or together, in various embodiments to allow the plug 12 to accept the socket 14 in a specified orientation, and vice versa. To this end, an option for the plug 12 is to form at least one of the feedthrough pins 42 with a different height or length relative to the other feedthrough pins 42 to create a symmetry break at a defined height. For example, the engagement feature 60 may be implemented by leaving one or more of the feedthrough pins 42 longer than the remaining feedthrough pins 42; such feedthrough pins 42 are referred to herein as elongated pins 142 for clarity (see FIGS. 1 and 4). For simplicity, one such elongated pin 142 is shown; however, in other configurations, two or more feedthrough pins 42 may be elongated.

[0030] 7, the use of elongated pins 142 allows socket 14 to include a radial end surface 340 connected to stepped radial mid-wall surface 140, optionally via axial wall 240. Radial mid-wall surface 140 may include at least one of receptacles 56, with the remaining receptacles 56 housed within and opening from radial end surface 340, as shown. Receptacle(s) 56 located on mid-wall surface 140 may be configured to accept elongated pins 142 (see FIG. 1) in this particular exemplary embodiment, with the identity of elongated pins 142 for connection to the short, long, common, getter, or grid nodes or feeds discussed above varying depending on the desired application.

[0031] The use of multiple such elongated pins 142 in this manner ensures that an operator can connect the socket 14 to the plug 12 of Figures 1, 2, and 4 in a specified orientation. This feature also "error-proofs" the installation by reducing the likelihood of or preventing incorrect connections of the type typically made by individual manual connections made using, for example, alligator clips or direct wire connections. However, the elongated pins 142 are only one possible implementation of the engagement feature 60.

[0032] For example, and briefly referring to the alternative engagement feature 600 of FIG. 8 , the plug 12 of FIGS. 1 , 2 , and 4 may include a keyed or splined surface 420, such as by forming the keyed or splined surface 420 on the surface of the central post 50 or another feedthrough pin 42. In such an embodiment, the socket 14 includes a mating keyed or splined surface 61, such that a designated orientation of the socket 14 allows the central post 50 to enter the corresponding receptacle 56. Other possibilities for implementing the engagement feature 60 may exist, and the use of the elongated pin 142 and / or the keyed / splined surfaces 420 and 61 are merely exemplary means for allowing the plug 12 to be coupled to the socket 14 in the designated orientation described above.

[0033] Referring to FIG. 9 , the center post 50 described above can be used as an indexable feature to ensure proper spacing and leveling of the feedthrough pins 42, for example, before fusing the stems 46 and sealing the feedthrough pins 42 therein. To facilitate installation, for example, the stems 46 can be leveled using a pin fixture 65 that indexes or aligns the stems 46 in the same orientation each time. Because the center post 50 is also used for alignment during later stages of manufacturing, including final sealing, the stems 46 need to maintain straight axial alignment. Such alignment is enabled by a representative pin fixture 65, such as a solid, planar base 66 connected to or integrally formed with an axially extending fixture post 68.

[0034] During operation, an operator can axially insert individual feedthrough pins 42 forming the plug 12 into mating openings 156 in the pin fixture—in this example, the fixture posts 68—through the stems 46, which are in fixed positions relative to one another, until the fixture posts 68 finally enter the plug recesses 44. The fixture has the same number of openings 156 as the feedthrough pins 42 because the fixture is designed to hold the feedthrough pins 42 in place while the stems 46 are sealed. As best shown in FIG. 10 , the radial surface 69 of the annular flange 45 then rests firmly on the base. The cathode assembly 10 shown in FIG. 10 (see also FIG. 1 ) is then electrically connected to the free ends E1 of the pass-through pins 42 extending from the stems 46 of FIG. 9 . This fixation and leveling approach may be contrasted with conventional approaches in which the stems 46 are leveled with the radial surface 69 of the glass flare component 40, which is rarely, if ever, perfectly flat. As a result, the cathode head 36 (see FIG. 1) may sometimes appear slightly curved, which may result in an uneven focus.

[0035] 11 illustrates an exemplary method 100 for constructing a vacuum tube insert assembly 10 for a vacuum tube, such as an x-ray tube, as described above with reference to, for example, FIGS. 1-10. A possible embodiment of method 100 begins at block B102 with providing a flared insert 40 having an annular flange 45 surrounding a plug recess 44 and a stem 46 integrally formed with and extending axially from annular flange 45, as best shown in FIG. 4. Method 100 then proceeds to block B104.

[0036] Block B104 involves axially inserting a plurality of feedthrough pins 42 through the stem 46 at fixed positions relative to one another such that the feedthrough pins 42 are collectively positioned within the plug recess 44 as the plug 12. In some embodiments of the method 100, this may involve inserting the feedthrough pins 42 into openings 156 in the pin retainer 65, with the pin retainer 65 having a fixed spacing between the openings 156 (see FIG. 9 ). The feedthrough pins 42 may then be pushed through the stem 56 using, for example, a pinch press. Thus, use of the pin retainer 65 has the advantage of maintaining the plane of the annular flange 45 in a perpendicular orientation relative to the central post 50. The method 100 then proceeds to block B106.

[0037] Block B106 includes sealing the stem 46 to the feedthrough pin 42 such that the stem 46 is vacuum-sealed to the feedthrough pin 42, thereby forming the plug 12. Sealing may involve forming a partially molten or viscous heat-softened glass of the stem 46 using a glass lathe and / or press, perhaps while the flared insert 40 is oriented, leveled, and held in the pin fixture 65 of FIG. 9 or a similar fixture. The stem 46 is thus vacuum-sealed to the feedthrough pin 42, with the feedthrough pin 42 extending through the surrounding glass of the stem 46 and with no intervening space therebetween to break the vacuum. The method 100 then proceeds to block B108.

[0038] 11 may involve connecting the feedthrough pin 42 to a corresponding connection on the cathode head 36 and then setting the filament(s) 39 therein. As described above, the feedthrough pin 42 is integrally formed with the heat-softened glass material of the stem 46 so that any potentially vacuum-depleting leak paths are sealed. Once the cathode assembly 28 is so connected, the method 100 proceeds to block B110.

[0039] At block B110, the method 100 includes completing the construction of the vacuum tube insert assembly 10. This may involve installing the remaining components of FIG. 1 in a non-limiting exemplary construction of an x-ray tube insert. For example, the anode assembly 26 of FIG. 1 may be threaded directly into the neck 33 and anode shank (not shown), while the cathode assembly 28 is placed on the center post 50. The stem 46 was leveled from the center post 50 using a pin fastener 65 so that the cathode head 36 is straight during sealing. As part of this effort, the flared insert 40 is connected to the glass envelope 24 of FIG. 1, thereby enclosing the cathode assembly 28 and the remaining components of FIG. 1 within the defined volume 25 of the glass envelope 24. The glass envelope 24 may be evacuated to form a vacuum. The method 100 then proceeds to block B112.

[0040] Block B112 of method 100 includes removably coupling a mating receptacle 56 of socket 14, best shown in FIG. 7, to feedthrough pins 42 of plug 12, which themselves reside within plug recess 44 (see FIG. 4). Power is thereby supplied to vacuum tube insert assembly 10.

[0041] 7 and 8, block B112 may include orienting the socket 14 in a specified orientation when connecting the socket 14 to the plug 12. Different configurations of the socket 14 may be used to perform different stages of assembly and testing, including final sealing, pumping, bakeout, radio frequency (RF), high pressure testing, and tanking, the latter being used for smoothing and removal of high field areas / irregularities such as small burrs.

[0042] Similarly, a different socket 14 would be used for vital sign-off such as voltage and pressure, and for connecting the vacuum tube insert assembly 10 to external power; the socket 14 would simply plug directly into the exposed plug 12 to effect the electrical connection. Loading would also be easier, as the operator would no longer need to feed individual wires through small holes in the insulator and individually connect the wires to the cathode assembly 28. Instead, the housing would be modified with the socket 14 plugging directly onto the feed-through pins 42, as described above.

[0043] According to one embodiment of the present disclosure, the vacuum tube insert assembly 10 includes a flared insert 40 having an annular flange 45 and a stem 46, each constructed from glass. The stem extends axially from the annular flange 45 and defines a plug recess 44. The annular flange 45 surrounds an outer periphery 47 of the plug recess 44. A plurality of feedthrough pins 42 are configured to connect to components of the vacuum tube insert assembly 10 and pass axially through and are sealed to the stem 46. The feedthrough pins 42 terminate a predetermined distance from the stem 46 inside the plug recess 44 to collectively form the plug 12. The socket 14 is configured to connect to the plug 12 within the plug recess 44, and the socket 14 includes a plurality of receptacles 56 collectively configured to removably couple to the feedthrough pins 42. The socket 14 or plug 12 include mating features 60, 600, separately or together, configured to allow the plug 12 to receive the socket 14 in a designated orientation of the socket 14.

[0044] In one embodiment, the feedthrough pins 42 include a central post 50 and one or more remaining feedthrough pins 52. The central post 50 has a radial dimension that exceeds the radial dimension of each of the remaining feedthrough pins 52. The central post 50 and the feedthrough pins 42, 52 may be cylindrical in a possible configuration, and the one or more remaining feedthrough pins 52 include four feedthrough pins.

[0045] In another embodiment, the socket 14 further includes a flexible cable 16 coupled to a plurality of receptacles 56 .

[0046] The plug 12 may include an engagement feature 60 configured to allow the plug 12 to receive the socket 14 in a specified orientation. In a possible embodiment, the engagement feature 60 includes at least one of the feedthrough pins 42 having an extended length relative to the respective lengths of the one or more remaining feedthrough pins 42. The engagement feature 60 may also include a stepped radially intermediate wall surface 140 that accommodates at least one of the receptacles 56, at least one of the receptacles 56 configured to receive therein a respective one of the feedthrough pins 42 having an extended length.

[0047] The plug 12 and socket 14 include engagement features 600, which in the disclosed embodiment include the keyed or splined surface 420 of the plug 12. The socket 14 in such an embodiment includes a mating keyed or splined surface 61 configured to receive the keyed or splined surface 420 of the plug 12 therein.

[0048] The feedthrough pins 42 may optionally be constructed from tungsten (W), molybdenum (Mo), or a nickel-cobalt-iron (Ni-Co-Fe) alloy.

[0049] In another possible embodiment, the feedthrough pin 42 is constructed from a first metal plated with a second metal.

[0050] As part of any of the above-described embodiments, the cathode assembly 28 may be surrounded by a glass envelope 24, and the flared insert 40 is connected to or integrally formed with the glass envelope 24. A feedthrough pin 42 is connected to the cathode assembly 28.

[0051] In one embodiment of the present disclosure, the vacuum tube insert assembly 10 is configured as an X-ray tube insert assembly 10.

[0052] According to another embodiment of the present disclosure, a method 100 for constructing a vacuum tube insert assembly 10 includes constructing a flared insert 40 and a stem 46 from glass, the flared insert 40 having an annular flange 45 surrounding a plug recess 44 and a stem 46 integrally formed with and extending axially therefrom. In this embodiment, the method 100 includes axially inserting a plurality of feedthrough pins 42 through the stem 46 in fixed positions relative to one another such that the feedthrough pins 42 are collectively positioned within the plug recess 44 as a plug 12, with at least one of the feedthrough pins 42 being longer than the remainder of the feedthrough pins 42. The method 100 also includes sealing the stem 46 to the feedthrough pins 42, thereby forming the plug 12. The method 100 may also include removably coupling a mating receptacle 56 of a socket 14 to the feedthrough pins 42 of the plug 12 of the vacuum tube insert assembly 10.

[0053] According to another embodiment of the present disclosure, a method 100 for constructing a vacuum tube insert assembly 10 includes constructing a flared insert 40 and a stem 46 from glass, the flared insert 40 having an annular flange 45 surrounding a plug recess 44 and a stem 46 integrally formed with and extending axially from the annular flange 45. The method 100 in this embodiment involves axially inserting a plurality of feedthrough pins 42 through the stems 46 in fixed positions relative to one another such that the feedthrough pins 42 are collectively positioned within the plug recess 44 as a plug 12. The method 100 also includes sealing the stems 46 to the feedthrough pins 42, thereby forming the plug 12. The socket 14 or plug 12 includes engagement features 60, 600, separately or together, configured to enable the plug 12 to receive the socket 14 in a specified orientation of the socket 14. The method 100 may also include removably coupling the mating receptacle 56 of the socket 14 to the feedthrough pin 42 of the plug 12 of the vacuum tube insert assembly 10 .

[0054] Axially inserting the plurality of feedthrough pins 42 through the stem 46 in fixed positions relative to one another may include inserting the feedthrough pins 42 into a plurality of openings 156 in the pin retainer 65, the pin retainer 65 having a fixed spacing between the openings 156, and pushing the feedthrough pins 42 through the stem 46.

[0055] In a possible embodiment, the method 100 includes connecting the feedthrough pin 42 to a corresponding connection on the cathode assembly 28 and connecting the flared insert 40 to the glass envelope 24, thereby enclosing the cathode assembly 28 within the volume 25 of the glass envelope 24.

[0056] In one embodiment, method 100 includes positioning socket 14 in a specified orientation via engagement features 60, 600 prior to connecting socket 14 to plug 12. Engagement features 60, 600 include at least one of feedthrough pins 142 that is longer than the remaining amount of feedthrough pins 42.

[0057] Removably coupling the mating receptacles 56 of the socket 14 to the feedthrough pins 42 of the plug 12 within the plug recess 44 includes, in a possible embodiment, inserting the elongated feedthrough pin 42 into one of the mating receptacles 56 located on the stepped radially intermediate wall surface 140 of the socket 14.

[0058] Removably coupling the mating receptacle 56 of the socket 14 to the feedthrough pin 42 of the plug 12 within the plug recess 44 may include inserting one or more keyed or splined surfaces 420 of the feedthrough pin 42 into one mating keyed or splined surface 61 of the mating receptacle 56.

[0059] Some embodiments of the disclosed vacuum tube insert assembly 10 include an annular flange means and a stem means. For example, the vacuum tube insert assembly can include a glass means including an annular flange means integrally formed with an axially extending stem means, the stem means defining a plug concave means. The annular flange means surrounds the outer periphery of the plug concave means. The plug means includes a plurality of feedthrough pin means that pass axially through the glass means, are sealed to the glass means, and terminate inside the plug concave means. The socket means can be configured to connect to the plug means within the plug concave means. The plurality of receptacle means of the socket means are configured to removably mate with the feedthrough pin means of the plug means. The socket means or plug means, separately or together, include engagement features configured to allow the plug means to receive the socket means in a specified orientation of the socket means, and vice versa.

[0060] The engagement feature means may optionally include a keyed or splined surface of the plug means and a mating keyed or splined surface of the socket means configured to receive the keyed or splined surface of the plug means therein.

[0061] An example of annular flange means includes annular flange 42. An example of stem means includes an axially extending stem 46 integrally formed with glass envelope 24, stem 46 defining plug concave means. Further, an example of plug concave means includes plug concave 44 described above, with annular flange means surrounding the outer periphery of the plug concave means. An example of plug means includes plug 12 described above including a plurality of feed-through-in means, an example of which includes feed-through pins 42 described above that pass axially through glass means, are sealed to the glass means, and terminate inside the plug concave means. Socket means in this embodiment of the disclosure, exemplified as socket 14, is configured to connect to plug means within the plug concave means. A plurality of receptacle means of the socket means are configured to removably couple to the feed-through pin means of the plug means, with an example of receptacle means being receptacle 56 described above.

[0062] The plug means in some embodiments includes engagement features configured to allow the plug means to receive the socket means in a specified orientation, examples of engagement features include engagement features 60, 600 described above.

[0063] The following provisions provide exemplary configurations of vacuum tube insert assemblies and methods for assembling vacuum tube insert assemblies as disclosed herein.

[0064] Clause 1: A vacuum tube insert assembly comprising: flared insert parts each having an annular flange and a stem constructed from glass, the stem extending axially from the annular flange and defining a plug concave surface, the annular flange surrounding an outer periphery of the plug concave surface; a plurality of feedthrough pins configured to couple to components of the vacuum tube insert assembly, the feedthrough pins passing axially through and sealed to the stem, the feedthrough pins terminating a predetermined distance from the stem inside the plug concave surface to collectively form a plug; and a socket configured to connect to the plug within the plug concave surface, the socket including a plurality of receptacles collectively configured to removably couple to the feedthrough pins, the socket or the plug separately or together including an engagement feature configured to enable the plug to receive the socket in a designated orientation of the socket.

[0065] Clause 2: A vacuum tube insert assembly as described in clause 1, wherein the feedthrough pin includes a central post and one or more remaining feedthrough pins, the central post having a radial dimension that exceeds the radial dimensions of each of the remaining feedthrough pins.

[0066] Clause 3: The vacuum tube insert assembly of clause 2, wherein the central post and the pin are cylindrical, and the one or more remaining feedthrough pins include four feedthrough pins.

[0067] Clause 4: A vacuum tube insert assembly as described in any one of clauses 1 to 3, wherein the socket further comprises a flexible cable coupled to the plurality of receptacles.

[0068] Clause 5: A vacuum tube insert assembly as described in any one of clauses 1 to 4, wherein the plug includes the engagement feature.

[0069] Clause 6: A vacuum tube insert assembly as described in clause 5, wherein the engagement feature includes at least one of the feedthrough pins having an extended length compared to the respective lengths of one or more remaining feedthrough pins.

[0070] Clause 7: A vacuum tube insertion assembly as described in Clause 6, wherein the engagement feature includes a stepped radially intermediate wall surface that accommodates at least one of the receptacles, and the at least one of the receptacles is configured to receive a respective one of the feedthrough pins having the extended length therein.

[0071] Clause 8: The vacuum tube insert assembly of clause 5, wherein the plug and the socket include the engagement features, the engagement features including a keyed or splined surface on the plug, and the socket includes a mating keyed or splined surface configured to receive the keyed or splined surface on the plug therein.

[0072] Clause 9: The vacuum tube insert assembly of any one of clauses 1 to 8, wherein the feedthrough pin is constructed from tungsten (W), molybdenum (Mo), or a nickel-cobalt-iron (Ni-Co-Fe) alloy.

[0073] Clause 10: A vacuum tube insert assembly as described in any one of clauses 1 to 9, wherein the feedthrough pin is constructed from a first metal that is plated with a second metal.

[0074] Clause 11: A vacuum tube insert assembly described in any one of clauses 1 to 10, further comprising a cathode assembly surrounded by a glass envelope, the flared insert being connected to the glass envelope or integrally formed with the glass envelope, and the feedthrough pin being connected to the cathode assembly.

[0075] Clause 12: The vacuum tube insert assembly of clause 11, wherein the vacuum tube insert assembly is configured as an X-ray tube insert assembly.

[0076] Clause 13: A method for constructing a vacuum tube insert assembly, the method comprising: constructing a flared insert and stem from glass, the flared insert having an annular flange surrounding a plug concave surface, the stem being integrally formed with and extending axially from the annular flange; axially inserting a plurality of feedthrough pins through the stem in fixed positions relative to one another such that the feedthrough pins are collectively positioned as a plug within the plug concave surface; and sealing the stem to the feedthrough pins, thereby forming the plug, the plug or mating socket including an engaging feature that enables the plug to receive the socket in a specified orientation.

[0077] Clause 14: The method of clause 13, wherein axially inserting the plurality of feedthrough pins through the stem at fixed positions relative to one another further comprises inserting the feedthrough pins into a plurality of openings in a pin lock, the pin lock having a fixed spacing between the openings, and pushing the feedthrough pins through the stem.

[0078] Clause 15: The method of either clause 13 or 14, further comprising removably coupling a mating receptacle of the socket to the feedthrough pin of the plug of the vacuum tube insert assembly.

[0079] Clause 16: The method of clause 15, further comprising positioning the socket in the specified orientation via the engagement features before connecting the socket to the plug, wherein the engagement features include at least one of the feedthrough pins being an elongated feedthrough pin that is longer than the remaining amount of the feedthrough pins.

[0080] Clause 17: The method of clause 15, wherein removably coupling the mating receptacles of the socket to the feedthrough pins of the plug within the plug concave surface includes inserting an elongated feedthrough pin into one of the mating receptacles located on a stepped radially intermediate wall surface of the socket.

[0081] Clause 18: A method according to any one of clauses 15 to 17, wherein removably coupling the mating receptacle of the socket to the feedthrough pin of the plug within the plug concave surface comprises inserting one or more keyed or splined surfaces of the feedthrough pin into mating keyed or splined surfaces of the mating receptacle.

[0082] Clause 19: A vacuum tube insert assembly comprising: glass means including annular flange means integrally formed with axially extending stem means, said stem means defining plug concave means, said annular flange means surrounding an outer periphery of said plug concave means; plug means including a plurality of feedthrough pin means axially passing through said glass means and sealed to said glass means and terminating inside said plug concave means; and socket means configured to connect said plug means within said plug concave means, wherein a plurality of receptacle means of said socket means are configured to removably mate with said feedthrough pin means of said plug means, and wherein said socket means or said plug means separately or together include engagement feature means configured to enable said plug means to receive said socket means in a designated orientation of said socket means.

[0083] Clause 20: A vacuum tube insert assembly as described in clause 19, wherein the engagement feature means includes a keyed or splined surface of the plug means and a mating keyed or splined surface of the socket means configured to receive the keyed or splined surface of the plug means therein.

[0084] While these systems and methods have been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various modifications may be made and equivalents may be substituted to adapt these teachings to other problems, materials, and techniques without departing from the scope of the claims. Features, aspects, components, or operations of one embodiment may be combined with features, aspects, components, or operations of other embodiments described herein. Accordingly, the present invention is not limited to the particular examples disclosed, but rather includes all embodiments falling within the scope of the appended claims.

[0085] The claims following this written disclosure are hereby expressly incorporated into this disclosure, with each claim standing on its own as a separate embodiment. This disclosure includes all variations of the independent claims with their dependent claims. Additionally, additional embodiments that may be derived from the following independent and dependent claims are also expressly incorporated into this description. These additional embodiments are determined by replacing the dependency of a given dependent claim with the phrase "any of the claims beginning with claim [x] and ending with the claim immediately preceding this claim," where the bracketed term "[x]" is replaced with the number of the most recently recited independent claim. For example, for the first set of claims beginning with independent claim 1, claim 3 depends on either claim 1 or 2, and these separate dependencies can result in two different embodiments; claim 4 depends on any one of claims 1, 2, or 3, and these separate dependencies can result in three different embodiments; claim 5 depends on any one of claims 1, 2, 3, or 4, and these separate dependencies can result in four different embodiments, and so on.

[0086] The recitation in a claim of the term "first" with respect to a feature or element does not necessarily imply the presence of a second, or additional, such feature or element. Where present, elements specifically recited in means-plus-function form are intended to be construed pursuant to 35 U.S.C. §112(f) to cover the corresponding structure, material, or acts described herein and their equivalents. The embodiments of the invention in which an exclusive right or privilege is claimed are defined as follows:

Claims

1. 1. A vacuum tube insert assembly comprising: a flared insert having an annular flange and a stem, each constructed from glass, the stem extending axially from the annular flange, an outer surface of the stem defining a plug concavity, and the annular flange surrounding an outer periphery of the plug concavity; a plurality of feedthrough pins configured to couple to components of the vacuum tube insert assembly, the plurality of feedthrough pins passing axially through the stem and sealed to the stem, the plurality of feedthrough pins including a continuous material extending a first distance from an inner surface of the stem opposite the outer surface and terminating a second distance from the outer surface of the stem within the plug concave surface to form a plug; a socket configured to connect to the plug within the plug concave surface, the socket including a plurality of receptacles configured to removably mate with the plurality of feedthrough pins, and the socket or the plug including, separately or together, engagement features configured to allow the plug to receive the socket in a designated orientation of the socket; 1. A vacuum tube insert assembly comprising:

2. 2. The vacuum tube insert assembly of claim 1, wherein the plurality of feedthrough pins includes a central post and one or more remaining feedthrough pins, the central post having a radial dimension that exceeds a radial dimension of each of the remaining feedthrough pins.

3. 3. The vacuum tube insert assembly of claim 2, wherein the central post and the one or more remaining feedthrough pins are cylindrical, and the one or more remaining feedthrough pins include four feedthrough pins.

4. 4. The vacuum tube insert assembly of claim 1, wherein the socket further includes a flexible cable coupled to the plurality of receptacles.

5. The vacuum tube insert assembly of claim 1 , wherein the plug includes the engagement feature.

6. 6. The vacuum tube insert assembly of claim 5, wherein the engagement feature includes at least one feedthrough pin of the plurality of feedthrough pins having an extended length compared to a respective length of one or more remaining feedthrough pins.

7. 7. The vacuum tube insert assembly of claim 6, wherein the engagement feature includes a stepped radially intermediate wall surface that accommodates at least one receptacle of the plurality of receptacles, the at least one receptacle of the plurality of receptacles configured to receive therein a respective feedthrough pin of the plurality of feedthrough pins having the extended length.

8. 6. The vacuum tube insert assembly of claim 5, wherein the plug and the socket include the engagement features, the engagement features including a keyed or splined surface on the plug, and the socket includes a mating keyed or splined surface configured to receive the keyed or splined surface on the plug therein.

9. 2. The vacuum tube insert assembly of claim 1, wherein said plurality of feedthrough pins are constructed from tungsten (W), molybdenum (Mo), or a nickel-cobalt-iron (Ni-Co-Fe) alloy.

10. 10. The vacuum tube insert assembly of claim 1, wherein said plurality of feedthrough pins are constructed from a first metal that is plated with a second metal.

11. further comprising a cathode assembly surrounded by a glass envelope; the flared insert is connected to or integrally formed with the glass envelope; the plurality of feedthrough pins are connected to the cathode assembly; 2. The vacuum tube insert assembly of claim 1, wherein the plurality of feedthrough pins extend into an interior volume of the vacuum tube insert assembly defined by the glass envelope and the interior surface of the stem.

12. The vacuum tube insert assembly of claim 11 , wherein the vacuum tube insert assembly is configured as an x-ray tube insert assembly.

13. 1. A method for constructing a vacuum tube insert assembly, comprising: constructing a flared insert and a stem from glass, the flared insert having an annular flange surrounding a plug concavity, the stem being integrally formed with and extending axially from the annular flange, the outer surface of the stem defining the plug concavity; axially inserting a plurality of feedthrough pins into the stem in fixed positions relative to one another so that the plurality of feedthrough pins are configured as a plug within the plug recess, the plurality of feedthrough pins including a continuous material extending a first distance from an inner surface of the stem opposite the outer surface and extending to terminate at a second distance from the outer surface of the stem within the plug recess; sealing the plurality of feedthrough pins to the stem to form the plug, wherein the plug or mating socket includes engagement features that enable the plug to receive the mating socket in a specified orientation, and the plurality of feedthrough pins of the plug are configured to removably couple to a plurality of mating receptacles of the mating socket; A method comprising:

14. The step of axially inserting the plurality of feedthrough pins into the stem at fixed positions relative to each other, comprising: inserting the plurality of feedthrough pins into a plurality of openings in a pin retainer, the pin retainer having a fixed spacing between the openings; pushing the plurality of feedthrough pins through the stem; 14. The method of claim 13, further comprising:

15. 15. The method of claim 13 or 14, further comprising removably coupling the plurality of mating receptacles of the mating socket to the plurality of feedthrough pins of the plug of the vacuum tube insert assembly.

16. 16. The method of claim 15, further comprising positioning the mating socket in the specified orientation via the engagement features before connecting the mating socket to the plug, the engagement features including at least one of the feedthrough pins being longer than the remaining feedthrough pins.

17. 16. The method of claim 15, wherein the step of removably coupling the plurality of mating receptacles of the mating socket to the plurality of feedthrough pins of the plug within the plug concave surface includes inserting an elongated feedthrough pin into one of the plurality of mating receptacles located in a stepped radially intermediate wall surface of the mating socket.

18. 16. The method of claim 15, wherein the step of removably coupling the plurality of mating receptacles of the mating socket to the plurality of feedthrough pins of the plug within the plug concave surface includes inserting a keyed or splined surface of one or more of the plurality of feedthrough pins into a mating keyed or splined surface of one or more of the plurality of mating receptacles.

19. 1. A vacuum tube insert assembly comprising: a glass envelope including an annular flange integrally formed with an axially extending stem, the stem including an outer surface defining a plug concavity, the annular flange surrounding an outer periphery of the plug concavity; a plug including a plurality of feedthrough pins that pass axially through the glass envelope and are sealed to the glass envelope, the plurality of feedthrough pins including a continuous material that extends a first distance from an inner surface of the stem opposite the outer surface and that extends a second distance from the outer surface of the stem and terminates within the plug concave surface; a socket configured to connect to the plug within the plug concave surface, wherein a plurality of receptacles of the socket are configured to removably mate with the plurality of feedthrough pins of the plug, and wherein the socket or the plug separately or together include engagement features configured to allow the plug to receive the socket in a designated orientation of the socket; 1. A vacuum tube insert assembly comprising:

20. 20. The vacuum tube insert assembly of claim 19, wherein the engagement features include a keyed or splined surface of the plug and a mating keyed or splined surface of the socket configured to receive the keyed or splined surface of the plug therein.

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