The present disclosure relates to preconnectorized optical cable assemblies with and methods of making by jacket segmentation.
Data center design and cabling-infrastructure architecture are increasingly large and complex, which requires incorporation of high density optical components (e.g., optical fiber densities), such as to compensate for limited space and meet increasing performance demands. Many data centers include fiber optic cables which have a number of advantages in waveguide systems compared to bulky traditional conductor cables (e.g., copper). Fiber optic cables provide wide bandwidth data transmission, transport multiple signals and traffic types, and/or deliver high-speed Internet access, especially as data rates increase. Data centers utilize multi-fiber cables to interconnect and provide signals between building distribution frames and/or to individual unit centers (e.g., computer servers). However, the labor and cost of deployment of such multi-fiber cable networks for a data center can be high. Thus, there is a desire to reduce the time and costs associated with data center construction, particularly regarding cabling installation.
One way to improve optical infrastructure installation efficiency is to pre-engineer infrastructure components. Such components (e.g., fiber optic cables) may be preterminated in a factory with connectors installed, tested, and packaged for fast, easy, and safe installation at a data center. In this way, the installer merely needs to unpacks the components, pull or route the preconnectorized fiber optic cable assembly, snap in connectors, and/or install patch cords to end equipment, etc. This saves a significant amount of time, effort, and costs compared to on-site connectorization and assembly of cables.
Pre-engineering such components presents challenges to decrease costs, waste, and/or effort in assembling such pre-configured multi-fiber optical cables to enable efficient handling, maintenance, and/or installation.
One embodiment of the disclosure relates to a method of making a distribution cable assembly. The method includes providing a cable bundle including a plurality of cable subunits. Each of the plurality of cable subunits includes at least one optical fiber. The cable bundle is devoid of an outer jacket of a distribution cable. The method further includes positioning a plurality of segments of a jacket of a distribution cable around the cable bundle. The method further includes attaching the plurality of segments together to form the jacket of the distribution cable.
An additional embodiment of the disclosure relates to a method of making a distribution cable assembly. The method includes circumferentially cutting a first ring cut at a first predetermined location in a base jacket surrounding a cable bundle. The cable bundle includes a plurality of subunit cables. Each of the plurality of subunit cables includes at least one optical fiber. The method further includes inserting a first insert jacket segment around the cable bundle within a first access window between two base jacket portions at least partially formed by the first ring cut. The first insert jacket segment includes a longitudinal slit and a first side opening. The method further includes joining the first insert jacket segment along the longitudinal slit. The method further includes attaching each end of the first insert jacket segment to the two base jacket portions to form the jacket of the distribution cable. The method further includes extending a first subunit cable of the plurality of subunit cables of the cable bundle through the first side opening.
Additional features and advantages will be set out in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the embodiments as described herein, including the detailed description which follows, the claims, as well as the appended drawings.
It is to be understood that both the foregoing general description and the following detailed description are merely exemplary, and are intended to provide an overview or framework to understanding the nature and character of the claims. The accompanying drawings are included to provide a further understanding, and are incorporated in and constitute a part of this specification. The drawings illustrate one or more embodiment(s), and together with the description serve to explain principles and operation of the various embodiments.
Reference will now be made in detail to the present preferred embodiments, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals will be used throughout the drawings to refer to the same or like parts.
The embodiments set out below represent the information to enable those skilled in the art to practice the embodiments. Upon reading the following description in light of the accompanying drawing figures, those skilled in the art will understand the concepts of the disclosure and will recognize applications of these concepts not particularly addressed herein. It should be understood that these concepts and applications fall within the scope of the disclosure and the accompanying claims.
The use herein of ordinals in conjunction with an element is solely for distinguishing what might otherwise be similar or identical labels, such as “first layer” and “second layer,” and does not imply a priority, a type, an importance, or other attribute, unless otherwise stated herein.
The term “about” used herein in conjunction with a numeric value means any value that is within a range of ten percent greater than or ten percent less than the numeric value.
As used herein, the articles “a” and “an” in reference to an element refers to “one or more” of the element unless otherwise explicitly specified. The word “or” as used herein is inclusive unless contextually impossible. As an example, the recitation of A or B means A, or B, or both A and B.
The phrase “surface” as used herein refers to an outermost portion of an item, and includes a thickness of the outermost portion of the item. The precise thickness is generally not relevant to the embodiments, unless otherwise discussed herein. For example, a layer of material has a surface which includes the outermost portion of the layer of material as well as some depth into the layer of material, and the depth may be relatively shallow, or may extend substantially into the layer of material. The sub-wavelength openings discussed herein are formed in a surface, but whether the depth of the sub-wavelength openings extends past the depth of the surface is generally not relevant to the embodiments.
It will be understood that when an element is referred to as being “connected” or “coupled” to another element, it can be directly connected or coupled to the other element or intervening elements may be present. In contrast, when an element is referred to as being “directly connected” or “directly coupled” to another element, there are no intervening elements present.
The use herein of “proximate” means at, next to, or near.
The terms “left,” “right,” “top,” “bottom,” “front,” “back,” “horizontal,” “parallel,” “perpendicular,” “vertical,” “lateral,” “coplanar,” and similar terms are used for convenience of describing the attached figures and are not intended to limit this disclosure. For example, the terms “left side” and “right side” are used with specific reference to the drawings as illustrated and the embodiments may be in other orientations in use. Further, as used herein, the terms “horizontal,” “parallel,” “perpendicular,” “vertical,” “lateral,” etc., include slight variations that may be present in working examples.
As used herein, the terms “optical communication,” “in optical communication,” and the like mean that two elements are arranged such that optical signals are passively or actively transmittable therebetween via a medium, such as, but not limited to, an optical fiber, connectors, free space, index-matching structure or gel, reflective surface, or other light directing or transmitting means.
As used herein, the term “port” means an interface for actively or passively passing (e.g., receiving, transmitting, or both receiving and transmitting) optical signals. A port may include, by way of non-limiting examples, one or more collimators, pigtails, optical connectors, optical splices, optical fibers, free-space, or a combination of the foregoing. In the context of a WDM assembly, a port is the location at which one or more optical signals enters and/or exist the WDM assembly.
As used herein, the term “pigtail” means one or more optical fibers that extend from a ferrule. The one or more optical fibers may each be terminated with a fiber optical connector but are not required to be terminated with a fiber optic connector.
In certain embodiments, a strain-relief component 110 may be disposed within the distribution interior 108 of the distribution jacket 106 between the cable bundle 102 of the subunit cables 104 and the distribution jacket 106. The strain-relief component 110 surrounds and/or is interspersed among the cable bundle 102 of the subunit cables 104. In certain embodiments, the strain-relief component 110 may be, for example, a layer of longitudinally-extending yarns for absorbing tensile loads on the cable bundle 102. In certain embodiments, the strain-relief component 110 includes a dispersed layer of aramid strands in the region between the distribution jacket 106 and the cable bundle 102 of subunit cables 104.
In the illustrated embodiment, the cable bundle 102 has eight subunit cables 104. However, other embodiments could include more or fewer subunit cables 104 depending on cabling requirements. In certain embodiments, one or more layers of subunit cables 104 may be provided depending on the fiber densities needed and/or other desired parameters (e.g., limitations on the outside diameter of the distribution cable 100). The distribution cable 100 and/or the subunit cables 104 may have generally circular cross-sections, although other cross-sections (e.g., oval, elliptical, etc.) may be used. The illustrated cables and subunit cables may not have perfectly circular cross-sections, and any citations of diameters may represent an average diameter of a generally circular cross-section. In certain embodiments, as illustrated, the cable bundle 102 is stranded such that the subunit cables 104 are helically twisted around a longitudinal axis of the cable bundle 102. In certain embodiments, an outer layer of a plurality of subunit cables 104 is stranded around an inner layer of subunit cables 104 to provide higher fiber densities. This reduces any stress or strain concentrations on any one subunit cable 104 (e.g., from bending of the distribution cable 100). In certain embodiments, a central strength element (not shown) may be provided and the subunit cables 104 may be stranded around the central strength element. In yet other cable applications, stranding may not be used and the subunit cables 104 may run substantially parallel through the distribution cable 100.
Referring to
In certain embodiments, a strain-relief component 120 may be disposed within the subunit interior 118 of the subunit jacket 116 between the subunit bundle 112 of the tether cables 114 and the subunit jacket 116. The strain-relief component 120 surrounds and/or is interspersed among the subunit bundle 112 of the subunit cables 104. In certain embodiments, the strain-relief component 120 may be, for example, a layer of longitudinally-extending yarns for absorbing tensile loads on the subunit bundle 112. In certain embodiments, the strain-relief component 120 includes a dispersed layer of aramid strands in the region between the subunit jacket 116 and the subunit bundle 112 of tether cables 114.
In certain embodiments, a central strength element 122 may be disposed in a center of the subunit bundle 112, and thereby within the subunit interior 118 of the subunit jacket 116. The tether cables 114 may be stranded (e.g., helically twisted) around the central strength element 122. In certain embodiments, an outer layer of a plurality of tether cables 114 is stranded around an inner layer of tether cables 114 to provide higher fiber densities. In yet other cable applications, stranding may not be used and the tether cables 114 may run substantially parallel through the subunit cable 104. The central strength element 122 provides strain-relief and absorbs loads from the tether cables 114.
In the illustrated embodiment, the subunit bundle 112 has six tether cables 114. However, other embodiments could include more or fewer tether cables 114 depending on cabling requirements. In certain embodiments, one or more layers of tether cables 114 may be provided depending on the fiber densities needed and/or other desired parameters (e.g., limitations on the outside diameter of the distribution cable 100). In certain embodiments, as illustrated, the subunit bundle 112 is stranded such that the tether cables 114 are helically twisted around a longitudinal axis of the subunit bundle 112. This reduces any stress or strain concentrations on any one tether cable 114 (e.g., from bending of the distribution cable 100 and/or subunit cable 104).
Each tether cable 114 includes one or more optical fibers 124 (may also be referred to herein as optical fiber waveguides). In certain embodiments, the optical fibers 124 in the subunit cable 104 may be furcated into separate tether cables 114 within the core of the subunit cable 104. Each tether cable 114 may include a tether jacket 126 to surround a select number of optical fibers 124 in the tether cable 114. As an example, as illustrated, each subunit cable 104 includes six tether cables 114, and each tether cable 114 includes two optical fibers 124. In other words, each subunit cable 104 includes 12 optical fibers 124. Other numbers of subunit cables 104, and/or tether cables 114, and/or optical fibers 124 can be employed for various applications, however. For example, in certain embodiments, each subunit cable 104 includes 2-24 optical fibers. Further, the diameters and thicknesses of the distribution cable 100, the subunit cables 104, and/or the tether cables 114 may vary according to the number of optical fibers 124 enclosed therein, and according to other factors.
In various embodiments, the distribution jacket 106, the subunit jacket 116, and/or the tether jacket 126 may be formed from an extrudable polymer material that includes one or more materials, additives, and/or components embedded in the polymer material that provides fire resistant characteristics, such as relatively low heat generation, low heat propagation, low flame propagation, and/or low smoke production. For example, the distribution jacket 106, the subunit jacket 116, and/or the tether jacket 126 may be made from a flame-retardant PVC. In various embodiments, the fire resistant material may include an intumescent material additive embedded in the polymer material. In other embodiments, the fire resistant material may include a non-intumescent fire resistant material embedded in the polymer material, such as a metal hydroxide, aluminum hydroxide, magnesium hydroxide, etc., that produces water in the presence of heat/fire which slows or limits heat transfer along the length of the distribution cable 100, subunit cables 104, and/or tether cables 114. In certain embodiments, the distribution jacket 106, the subunit jacket 116, and/or the tether jacket 126 may be formed from fire-retardant materials to obtain a desired plenum burn rating. For example, highly-filled PVCs of specified thicknesses can be used to form these components. Other suitable materials include low smoke zero halogen (LSZH) materials such as flame retardant polyethylene and PVDF.
In certain embodiments, the strain-relief component 110 and/or strain-relief component 120 may utilize tensile yarns as tension relief elements that provide tensile strength to the cables 100, 104, 114. In certain embodiments, a preferred material for the tensile yarns is aramid (e.g., KEVLAR®), but other tensile strength materials could be used, such as high molecular weight polyethylenes (e.g., SPECTRA® fiber and DYNEEMA® fiber, Teijin Twaron® aramids, fiberglass, etc.). In certain embodiments, the yarns may be stranded to improve cable performance.
The components of the distribution cable 100, such as the subunit cables 104, can be constructed of selected materials of selected thicknesses such that the distribution cable 100 achieves plenum burn ratings according to desired specifications. The subunit cables 104 can also be constructed so that they are relatively robust, such that they are suitable for field use, while also providing a desired degree of accessibility. For example, in certain embodiments, the subunit cables 104 can be constructed with thicker subunit jackets 116 which provide sufficient protection for the fibers such that the subunit jackets 116 may be used as furcation legs.
The distribution connectors 308(1)-308(8) are in optical communication with the tap connectors 314(1)-314(8) (may be referred to generally as tap connectors 314), where the distribution cable assembly 300 is pre-connectorized, such as for connection to a patch panel (e.g., at a goalpost). Any conventional or yet-to-be developed optical connector or connectorization scheme may be used in accordance with the present disclosure, including, but not limited to, small (e.g., LC) and multi-fiber (e.g., MPO/MTP) connectors as commercially available. The distribution cable assembly 300 includes a distribution portion 317 of the subunit cable 104 that extends from the distribution connectors 308(1)-308(8) through the distribution cable 100. The distribution cable assembly 300 further includes tap portions 318(1)-318(8) of the subunit cable 104 that extends from the distribution cable 100 to the tap connectors 312(1)-312(8). A junction shell 322(1)-322(8) at each tap point 320(1)-320(8) facilitates and protects routing of the subunit cable 104 from the distribution cable 100.
In certain embodiments, as illustrated in
In certain embodiments, as illustrated in
The entrance room 404 communicates with a Main Distribution Area (MDA) 406. The MDA 406 may be separately contained in a dedicated computer room 408. In some cases, the entrance room 404 may be combined with the MDA 406. The MDA 406 is the central point of distribution for the data center structured cabling system. Core routers, core Local Area Network (LAN) switches, core Storage Area Network (SAN) switches, and Private Branch eXchange (PBX) may be located in the MDA 406. The MDA 406 may serve one or more Horizontal Distribution Areas (HDAs) 410 or Equipment Distribution Areas (EDAs) 412. The HDA 410 may include LAN switches, SAN switches, and Keyboard/Video/Mouse (KVM) switches for equipment located in the EDAs 412. In a small data center, the MDA 406 may serve the EDAs 412 directly with no HDAs 410. However, most data centers, particularly large data centers, will have multiple HDAs 410. The EDA 412 contains the end equipment, including computer systems and telecommunications equipment typically organized in racks or cabinets. In some cases, a Zone Distribution Area (ZDA) 414 may be provided between the HDA 410 and the EDA 412 to provide for frequent reconfiguration and flexibility.
The cabling topology for a data center includes many different types of cabling, such as high fiber count cables (e.g., 3,000+ fibers) coming into the data center and all the structured cabling to connect all of the switches and equipment internal to the data center. The data center structured cabling may be categorized as backbone cabling and horizontal cabling.
The most efficient optical infrastructure is one in which all or most of the components are preterminated in the factory and the cables are designed to fit efficiently in the confined spaces of the datacenter without excess cable. In certain embodiments, all connectors are installed and tested in the factory and packaged such that components are not damaged during installation. The installer simply unpacks the components, pulls the preconnectorized cable assembly into place, snaps in all of the connectors and the system is up and running. Accordingly, the cable assembly 300, 300′, 300″ depicted in
In certain embodiments, the plurality of tap subunits 304 (e.g., premanufactured) of the distribution cable assembly 300 are spaced apart by a predetermined distance S and/or of a predetermined length L based on, for example, location in a datacenter and/or distance to specific equipment, etc. In particular, the distribution cable assembly 300 could be manufactured such that each individual tap subunit 304 has a predetermined length L according to the configuration of the data center and where along the distribution cable 100 the tap subunit 304 will branch away. Further, the tap subunits 304 may be premanufactured such that each has a predetermined length L according to the configuration of the data center (e.g., spacing S between servers) and location along the distribution cable.
Although the concepts of the present disclosure are described herein with primary reference to a data center, it is contemplated that the concepts will enjoy applicability to any outdoor and indoor waveguide system associated with digital infrastructure data including an infrastructure layout and housing server rack systems. For example, and not by way of limitation, it is contemplated that the concepts of the present disclosure will enjoy applicability to indoor warehouses and/or commercial buildings.
In certain embodiments, some of the jacket segments 600A-602D are through jacket segments 600A-600D (referred to generally as through jacket segment 600) without a side opening, and some of the jacket segments are windowed jacket segments 602A-602D (referred to generally as windowed jacket segment 602), where each windowed jacket segment 602A-602D includes a side opening 506 at the first end 608 extending at least partially around a circumference of the windowed jacket segment 602A-602D. In certain embodiments, all of the jacket segments 600A-602D are windowed jacket segments 602. A longitudinal length of each of the jacket segments 600A-602D may be configured according to where the tap points 320 are required.
In certain embodiments, the cable bundle 102 is fed through all of the jacket segments 600A-602D. Then, for example, a subunit cable 104 is cut at a second end 610 of a windowed jacket segment 602A and withdrawn through the windowed jacket segment 602A to the first end 604 of the through jacket segment 600A. Accordingly, in certain embodiments, the length of the windowed jacket segment 602A is based on the desired length of the tap portion 318 of the subunit cable 104. Of course, the subunit cable 104 may be tailored further (e.g., additionally cut) as needed. The process may be repeated as necessary based on the number of tap points 320 to be branched from the distribution cable 100. In such a configuration, the lengths of the through jacket segment 600 and the windowed jacket segment 602 determines the relative positions of the side openings 506 (and the relative positions of the tap points 320). In certain embodiments, these relative positions are preconfigured based on a predetermined length (such as corresponding to a data center layout).
Referring to
Referring to
In certain embodiments, rather than cut the subunit cable 104 from the cable bundle 102, the subunit cables 104 are instead individually fed down each of the jacket segments 600A-602D. In such a configuration, the cable bundle 102 is formed during the assembly of the distribution cable 100 rather than pulled from the cable bundle.
In certain embodiments, pre-cutting the distribution jacket 106 into smaller segments and placed close together may require less space to manufacture (e.g., have a smaller footprint).
Then, for example, a subunit cable 104 (see
In certain embodiments, after the first through jacket segment 600A is positioned over the cable bundle 102, the subunit cable 104 is cut from the cable bundle 102 and peeled away from the cable bundle 102. The second through jacket segment 600B is then positioned around the cable bundle 102 with the first end 604 of the second jacket segment 600B positioned proximate the second end 606 of the first through jacket segment 600A.
Regardless of which process is used, windowed jacket segments 602 are then positioned between at least some of the through jacket segments 600 and around the cable bundle 102. The through jacket segments 600 and the windowed jacket segments 602 are then attached to one another (e.g. by coupling shell 500, junction shell 502, welding, glue, etc.). In such a configuration, the lengths of the through jacket segment 600 and the windowed jacket segment 602 determine the relative positions of the side openings 506 (and the relative positions of the tap points 320 (see
Referring to
Step 1104 includes cutting each subunit cable of the plurality of subunit cables 104 from the cable bundle 102 at a different longitudinal location to create a plurality of longitudinally spaced tap points 320. Step 1106 includes positioning a plurality of jacket segments 600A-602D of a distribution cable 100 around the cable bundle 102. In certain embodiments, at least one of the plurality of jacket segments 600A-602D includes a plurality of side openings 506.
Step 1108 includes extending one subunit cable of the plurality of subunit cables 104 through each of the plurality of side openings 506. Step 1110 includes attaching the plurality of jacket segments 600A-602D together to form the jacket of the distribution cable 100. In certain embodiments, the plurality of jacket segments 600A-602D are attached together by at least one of welding or gluing. Step 1112 includes covering each of the plurality of side openings 506 with a junction shell 502 by attachment of the junction shell 502 to the jacket of the distribution cable 100.
In certain embodiments, the method further includes sliding a tap jacket 1000 over at least a portion of each of the plurality of subunit cables 104 extending through the plurality of side openings 506. In certain embodiments, the method further includes furcating a plurality of fibers of each subunit cable of the plurality of subunit cables 104 into tether subunits. In certain embodiments, the method further includes connectorizing each of the plurality of subunit cables 104 with a distribution connector 308 at a distribution end 310 and a tap connector 314 at a tap end 316. In certain embodiments, the plurality of subunit cables 104 comprises eight subunit cables 104, each subunit cable 104 including 12 fibers furcated into six 2-fiber tether subunits, each of the plurality of subunit cables 104 extending through a respective one of the plurality of side openings 506.
Step 1204 includes inserting a first insert jacket segment around the cable bundle 102 within a first access window 700 between two base jacket portions 800A-800B at least partially formed by the first ring cut 800(1). The first insert jacket segment includes a longitudinal slit 702 and a first side opening 506. In certain embodiments, the first access window 700 is formed by sliding the two base jacket portions 800A-800B apart. In certain embodiments, the method further includes circumferentially cutting a second ring cut 800(2) to form a base jacket segment 902 between the first ring cut 800(1) and the second ring cut 800(2), longitudinally cutting a slit 702 in the base jacket segment 902 between the first ring cut 800(1) and a second ring cut 800(2), and removing the base jacket segment 902 of the base jacket from around the cable bundle 102 to form the first access window 700.
In certain embodiments, the method further includes cutting the first subunit cable 104 of the plurality of subunit cables 104 from the cable bundle 102 to create a tap point 320, and extending the first subunit cable of the plurality of subunit cables 104 through the first side opening.
Step 1206 includes joining the first insert jacket segment along the longitudinal slit 702. Step 1308 includes attaching each end of the first insert jacket segment to the two base jacket portions 800A-800B to form the jacket of the distribution cable 100. In certain embodiments, the first insert jacket segment is attached to the two base jacket portions 800A-800B of the base jacket by at least one of welding or gluing.
Step 1210 includes extending a first subunit cable of the plurality of subunit cables 104 of the cable bundle 102 through the first side opening. Step 1212 includes covering the first side opening with a junction shell 502 by attachment of the junction shell 502 to one of the two base jacket portions 800A-800B and the first insert jacket segment.
In certain embodiments, the method further includes sliding a tap jacket 1000 over at least a portion of the first subunit cable of the plurality of subunit cables 104 extending through the first side opening 506. In certain embodiments, the method further includes furcating a plurality of fibers of the first subunit cable of the plurality of subunit cables 104 into tether subunits. In certain embodiments, the method further includes connectorizing the first subunit cable of the plurality of subunit cables 104 with a distribution connector 308 at a distribution end 310 and a tap connector 314 at a tap end 316. In certain embodiments, the plurality of subunit cables 104 comprises eight subunit cables 104, each subunit cable 104 including 12 fibers furcated into six 2-fiber tether subunits, each of the plurality of subunit cables 104 extending through a respective one of the plurality of side openings 506.
It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit or scope of the invention.
Further, as used herein, it is intended that terms “fiber optic cables” and/or “optical fibers” include all types of single mode and multi-mode light waveguides, including one or more optical fibers that may be upcoated, colored, buffered, ribbonized and/or have other organizing or protective structure in a cable such as one or more tubes, strength members, jackets or the like. Likewise, other types of suitable optical fibers include bend-insensitive optical fibers, or any other expedient of a medium for transmitting light signals. An example of a bend-insensitive, or bend resistant, optical fiber is ClearCurve® Multimode fiber commercially available from Corning Incorporated. Suitable fibers of this type are disclosed, for example, in U.S. Patent Application Publication Nos. 2008/0166094 and 2009/0169163.
Many modifications and other embodiments of the concepts in this disclosure will come to mind to one skilled in the art to which the embodiments pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the description and claims are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
This application is a continuation of International Patent Application No. PCT/US2021/018309 filed Feb. 17, 2021, which claims the benefit of priority of U.S. Provisional Application No. 62/986,118, filed on Mar. 6, 2020, the content of which is relied upon and incorporated herein by reference in its entirety.
Number | Date | Country | |
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62986118 | Mar 2020 | US |
Number | Date | Country | |
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Parent | PCT/US2021/018309 | Feb 2021 | US |
Child | 17893510 | US |