Patent ID: 12256510

The figures are not necessarily to scale. Like numbers used in the figures may be used to refer to like components. However, it will be understood that the use of a number to refer to a component in a given figure is not intended to limit the component in another figure labeled with the same number.

DETAILED DESCRIPTION

Various exemplary embodiments of the disclosure will now be described with particular reference to the drawings. Exemplary embodiments of the present disclosure may take on various modifications and alterations without departing from the spirit and scope of the disclosure. Accordingly, it is to be understood that the embodiments of the present disclosure are not to be limited to the following described exemplary embodiments, but are to be controlled by the features and limitations set forth in the claims and any equivalents thereof.

Unless otherwise indicated, all numbers expressing feature sizes, amounts, and physical properties used in the specification and claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the foregoing specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by those skilled in the art utilizing the teachings disclosed herein.

As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” encompass embodiments having plural referents, unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term “or” is generally employed in its sense including “and/or” unless the content clearly dictates otherwise.

Spatially related terms, including but not limited to, “lower,” “upper,” “beneath,” “below,” “above,” and “on top,” if used herein, are utilized for ease of description to describe spatial relationships of an element(s) to another. Such spatially related terms encompass different orientations of the device in use or operation in addition to the particular orientations depicted in the figures and described herein. For example, if an object depicted in the figures is turned over or flipped over, portions previously described as below or beneath other elements would then be above those other elements.

Cartesian coordinates are used in some of the Figures for reference and are not intended to be limiting as to direction or orientation.

For purposes of description herein, the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” “top,” “bottom,” “side,” and derivatives thereof, shall relate to the disclosure as oriented with respect to the Cartesian coordinates in the corresponding Figure, unless stated otherwise. However, it is to be understood that the disclosure may assume various alternative orientations, except where expressly specified to the contrary.

For the purposes of describing and defining the subject matter of the disclosure it is noted that the terms “substantially” and “generally” may be utilized herein to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation.

FIGS.1and2illustrate an embodiment of a closure1000A in which a plurality of sealing segment assemblies300can be mounted to form a sealing system1000. The closure1000A includes a cover assembly100, an endcap200or base coupled to the cover assembly100, a plurality of sealing segment assemblies300disposed within slotted areas250of the endcap200, and a plurality of cables400(FIG.1) at least some of which are configured to route through at least one sealing segment assembly and form a cable port seal500.

Other components may also be included in the closure, as will be further described herein. The plurality of sealing segment assemblies300is mounted to the endcap200such that together or upon combination, the plurality forms a substantially continuous sealing perimeter around the endcap, i.e. with minimal gaps between sealing elements contained in the sealing system.

The cover assembly100is removable from the endcap200. The cover assembly100includes a cover120or cannister, a clamping ring140, a cover fastener160, and a cover sealing element180. In this exemplary embodiment, the cover is a dome-type cover, which extends upwardly and around the endcap to enclose various components contained therein.

The clamping ring140is positionable over a portion of the cover120and includes a clamping arm142. Disposed in the clamping arm142is an aperture144configured to hold the cover fastener160. The cover fastener160is configured to mechanically hold at least a portion of the clamping arm142together such that the clamping arm applies force against the cover sealing element180and the endcap, as schematically shown inFIG.2. The cover fastener may have a nut and bolt configuration or may be a screw or some other type of mechanical fastener. The cover sealing element180includes an outer sealing portion182, an upper sealing portion184, a middle sealing portion186, and a lower sealing portion188. Each sealing portion of the cover sealing element extends toward the clamping arm142to apply a force, as schematically represented by arrow R, as shown inFIG.2. Arrows G1, G2, Y1, Y2further schematically represent the forces in the sealing system when assembled with the cover assembly.

The endcap200and the cover assembly100cooperate to define an interior when the cover assembly100is mounted to the endcap200. The interior is of sufficient size and shape to contain a variety of components, which are commonly included in fiber optic closures. Such components include, but are not limited to strain relief assemblies, splice trays, splitters, wavelength division multiplexers, etc.

FIGS.3,4A, and5-7further illustrate the sealing system1000with the cover assembly removed. The endcap200includes an endcap body210having a plurality of slotted areas250disposed therein. In the embodiment as shown particularly inFIG.5, the endcap200includes eight slotted areas250. The number of slotted areas included in the endcap, however, should not be construed as limiting. Fewer or additional slotted areas can be included in the endcap depending upon application requirements, the size or footprint of the closure, manufacturing parameters, etc.

FIG.4Aillustrates a portion of the endcap body210with additional detail included in each slotted area250. The endcap body210includes an outer endcap rim212having an upwardly extending edge214and an inner endcap step216positioned higher than the outer endcap rim212. A portion of each slotted area has a curved profile CP, having a semi-circular section. A plurality of elongated notches220is positioned at intervals along the inner surface of each slotted area250. At least some of the notches are preferably configured to engage with complimentary surfaces of each respective sealing segment assembly300. Extending from end faces222of the endcap are tangs224, which facilitate alignment and connection of the sealing segment assembly300into the slotted area250.

Referring particularly toFIG.4B, each sealing segment assembly300includes an inner segment310and an outer segment350that mate together. Each inner segment310has an upper segment portion312, a lower segment portion314, and an inner segment seal318disposed between the upper segment portion312and the lower segment portion314. Each upper segment portion312, lower segment portion314, and inner segment seal318has an arc shape and substantially flat forward-facing surfaces that allow for mating of the inner segment310with the outer segment350. The upper segment portion312and the lower segment portion314also include a plurality of protruding mating elements320configured for insertion into the upper segment element362of the outer segment350.

Still referring toFIG.4B, each outer segment350has an upper segment element362, an outer perimeter element354, and an outer segment seal356disposed between the upper segment element362and the outer perimeter element354. Each upper segment element362, outer perimeter element354, and outer segment seal356has an arc shape and substantially flat forward-facing surfaces that allow for mating of the inner segment310with the outer segment350. The upper segment element362and the outer perimeter element354also include a plurality of openings360configured to receive the protruding mating elements320of the inner segment310. The upper segment element362also includes protruding mating elements364configured for positioning within the elongated slots of the endcap.

Upon assembly, the inner segment310and the outer segment are configured to provide a sealing segment assemblies, which each act as a sealed cable port370, allowing at least one cable to pass through in a sealed state, as particularly shown inFIG.3.FIG.6shows the sealing segment assemblies in activated and released positions, with the activated positioning being schematically represented by arrows L1, L2, L3. A compressive force is applied to the sealing segment assembly to compress the sealing elements contained therein and move the sealing segment assembly downward.

In embodiments, the sealing elements shown and described herein may be manufacturing from one or materials having a Shore 000 hardness in the range of 20-80 or 30-60. The one or materials may have a compression set less than or equal to 10 percent, less than or equal to 15 percent, or less than or equal to 20 percent. Any material that meets these Shore 000 hardness and compression set requirements can be used.

In embodiments, the sealing elements are manufactured from a composition that includes a dry silicone gel or a polyurethane gel. As used herein, the term “dry silicone gel” may refer to a chemically crosslinked polymer having a Si—O backbone and comprising a relatively low amount, or no amount at all, of diluent fluids such as silicone oil or mineral oil. As opposed to carbon-based polymers, the crosslinked silicone polymers of dry silicone gels are based on a Si—O backbone. The characteristics of silicon and oxygen provide crosslinked polymers with their exceptional properties. For example, silicon forms stable tetrahedral structures, and silicon-oxygen bonds are relatively strong which results in dry silicone gels with high temperature resistance. In addition, crosslinked Si—O polymers have a relatively high chain flexibility as well as low rotational energy barrier.

The dry silicone gels may be made according to a number of different polymerization reactions. In certain embodiments, the polymerization reaction is a hydrosilylation reaction, also referred to as a hydrosilation reaction. In some embodiments, the hydrosilylation reaction makes use of a platinum catalyst, while other embodiments make use of radicals. In further embodiments, the dry silicone gel is made by a dehydrogenated coupling reaction. In other embodiments, the dry silicone gel is made by a condensation cure RTV reaction.

In certain embodiments, the dry silicone gel is made by reacting at least a crosslinker, a chain extender, and a base polymer (e.g., a vinyl-terminated polydimethylsiloxane). In certain embodiments, a catalyst is included to speed up the reaction. In additional embodiments, an inhibitor may be used to slow down the rate of reaction.

Polyurethane gels are typically formed from the reaction of a polyfunctional organic isocyanate with a polyfunctional isocyanate reactive material in the presence of a non-volatile inert liquid. The polyurethane component of the gel is typically cross-linked (thermoset) and the isocyanate reactive material contributes to flexibility. The loading of the non-volatile inert liquid in polyurethane gels is typically quite high. It is almost always higher than 10% by weight of the total gel composition, and is typically higher than 30% by weight of the total gel composition. Plasticizer loadings of greater than 50% of the total composition are well known. Plasticizers (typically inert, non-volatile liquids) that have been used in the past in preparing polyurethane gels include phthalate plasticizers (such as DIOP), vegetable oils, mineral oils, liquid resins such as polybutene resins, other kinds of ether and ester containing liquids, mixtures of these, and the like. [0119] For example, polyurethane gel can be made by gelling a mixture comprising conventional curable polyurethane precursor materials in the presence of substantial quantities of a mineral or vegetable oil or a mixtures thereof (e.g., in an amount of 60 to 80%) or a suitable plasticizer, e.g., a trimellitate such as n-octyl-n-decyl trimellitate (e.g., in an amount of 30 to 70%).

In some embodiments, the sealing element material(s) (e.g., a dry silicone gel or a polyurethane gel) has/have a hardness in the range of 20 to 80 Shore 000. In some embodiments, the sealing element material(s) (e.g., a dry silicone gel or a polyurethane gel) has/have a hardness in the range of 30 to 60 Shore 000. In other embodiments, the sealing element material(s) (e.g., a dry silicone gel or a polyurethane gel) has/have a hardness in the range of 37 to 45 Shore 000. In yet other embodiments, the cable sealing insert material (e.g., a dry silicone gel or a polyurethane gel) has a hardness in the range of 38 to 42 Shore 000. Shore 000 hardness referenced herein is residual hardness measured according to ASTM D2240 with a 30 second hold time.

In some embodiments, the cable sealing insert material (e.g., a dry silicone gel or a polyurethane gel) is compressed to about 50% of its original height. This causes a certain stress in the material. The stress is now reduced because the material relaxes. In certain embodiments, the stress relaxation of the cable sealing insert material is 20% to 70% when subjected to compression to about 50% of the original height of the material at 85° C., wherein the stress relaxation is measured after a one minute hold time. In certain embodiments, the stress relaxation of the cable sealing insert material is 30 to 60% when subjected to compression to about 50% of the original height of the material at 85° C., wherein the stress relaxation is measured after a one minute hold time. In other embodiments, the stress relaxation of the cable sealing insert material is 40% to 60% when subjected to compression to about 50% of the original height of the material at 85° C., wherein the stress relaxation is measured after a one minute hold time. A higher stress relaxation indicates that once a cable sealing insert material is installed in an enclosure, the cable sealing insert material will require less stress in order for it to seal.

Sealing materials (i.e., gel materials) that may be used for cable ports in accordance with the present disclosure can have certain material properties adapted to facilitate cable size range taking and reliable sealing in systems that optionally may not include a separate actuator for pressurizing the seal and for maintaining pressure on the sea lover extended times. For example, exemplary sealant materials can be defined by properties such as hardness, compression set, resistance to extrusion, elongation to failure, and oil bleed out properties.

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 disclosure. Since modifications, combinations, sub-combinations and variations of the disclosed embodiments incorporating the spirit and substance of the disclosure may occur to persons skilled in the art, the embodiments disclosed herein should be construed to include everything within the scope of the appended claims and their equivalents.