Patent ID: 12252008

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

This application is directed to reducing ingress of debris, such as sand, dust and grit, into an interface that is provided between an outside surface of a neck portion of a fuel tank and a surface applying a load to the outside surface. The outside surface may be a cylindrical surface of a boss and the load applying surface may be a bearing or a component of a mounting block or mounting block assembly configured to support at least a portion of the weight of the tank. The ingress of such matter can produce wear at the neck portion of the fuel tank. Neck portion wear can lead to accelerated wear of the fuel tank or fuel system in which the tank is integrated, and/or to maintenance concerns of the fuel tank and/or fuel system. The incidence and severity of these outcomes can be reduced or eliminated by embodiments disclosed herein.

FIGS.1and2illustrate environments in which embodiments herein can be deployed. In one example, a fuel system50can be coupled with a vehicle10to provide the fuel needs therefor. In various embodiments, a vehicle10may refer to any mobile machine or device, including trailers and other towable assemblies, designed or used to transport passengers or cargo, including fuel. Examples of a vehicle may include cars, trucks, buses, trains, ships, boats, aircrafts and other types of vehicles as well as trailer and other component that can be towed by or coupled to any of the foregoing. More generally, the fuel system50could be part of a stationary facility for storage of fuel and/or for refueling a fleet. The vehicle10inFIG.1is a tractor-trailer. Classes of trucks that could benefit from the disclosed improvements herein include a light duty trucks (e.g., class 1, class 2 or class 3), medium duty trucks (e.g., class 4, class 5 or class 6), or heavy duty trucks (e.g., class 7 or class 8). Passenger vehicles, including cars, wagons, vans, buses, high-occupancy vehicles could employ the disclosed improvements as well. The vehicle10can be any vehicle, as discussed above, but is illustrated as a tractor-trailer with a cab18and a detachable portion22, i.e., the trailer. The fuel system50is disposed between the cab18and the detachable trailer22but could be in other locations in other fuel systems. The connection to the vehicle10can be by way of mounting brackets51disposed on a lower portion of the fuel system50. The fuel system50can include one or a plurality of fuel tanks52disposed in an enclosure53. The fuel tanks52may be of any size, capacity, shape and/or weight and may be made of any suitable material. For example, the fuel tanks52may have a shape that is substantially cylindrical, rectangular, spherical, or the like. In addition, the fuel tank(s)52may be used to store any type(s) of fuel such as gaseous fuels (e.g., compressed natural gas) or a liquid (e.g., diesel). For example, gaseous fuels may include hydrogen or hydrogen based gas, hythane, H2CNG, or any other gas. The enclosure53can be mounted to a structure, e.g., to a support frame of the fuel system50.

In one embodiment, the fuel system50includes a mounting assembly62that can include or be supported by a frame64. The mounting assembly62can include a block member(s) that receives and retains one or more boss members of the fuel tank52. The mounting assembly62can be coupled to the mounting brackets51, e.g., by the first boss54or by other frame members between the frame64and the mounting brackets51.

FIGS.2A,3, and3Ashow details of how the fuel tank52can be supported by a mounting block such as the mounting assembly62and/or the frame64and/or block members as discussed further below. The fuel tank52includes a first end52A and a second end52B. A cylindrical portion is disposed between the first end52A and the second end52B. The cylindrical portion can account for the majority of the volume of the fuel tank52. The ends of the fuel tank52can be enclosed by hemispherical dome members at the first end52A and the second end52B. A first boss54can be disposed at the first end52A. A second boss58can be disposed at the second end52B. Each boss can have an outer surface, e.g., the first boss54can have an outer surface56that is exposed and that is coupled to the mounting assembly62as discussed below.

FIG.3Aschematically shows how a fixed bearing block assembly66can be integrated into the mounting assembly62to support the fuel tank52at the second boss58. The fixed bearing block assembly66can include a rigid block member68. In one embodiment the fixed bearing block assembly66includes a two part assembly that includes two rigid block members68. A first rigid block member68is disposed generally above the second boss58when applied and a second rigid block member68is disposed generally below the second boss58. The two rigid block members68can be identical, such that each provides one half of an inner periphery70configured to be disposed about the second boss58. In some embodiments the first and second rigid block members68have a “C” shape profile when separated. The “C” shape refers to one or each of the block members68having a convex surface, such as one-half or a portion of the inner periphery70and also having external sides disposed about the inner periphery70or portion thereof. Each block member68can have a first side or portion68A of an outer periphery thereof disposed opposite the inner periphery70. Each block member68can have a second68B and third side68C disposed opposite of each other and at opposite ends of the first side68A. The two rigid block members68can be similar or identical such that each provides a similar or identical outer periphery configured to be secured to the frame64or other supporting structure within the mounting brackets51of the fuel system50. Apertures in the outer periphery of the rigid block member(s)68can allow bolts or other fasteners to secure the two or more rigid block members68together. In another embodiment, the fixed bearing block assembly66is a single member with an aperture in a center thereof providing the inner periphery70.

The inner periphery70can be provided with a boss engaging feature72, which can be one or a plurality of inner threads76. The inner threads76can be configured to mate with the second boss58to limit, reduce or eliminate relative movement between the second boss58and the fixed bearing block assembly66. In one case, the second boss58comprises one or a plurality of outer threads74that can mate with the boss engaging feature72, e.g., with the inner threads76. In one case, the inner threads76are female threads and the outer threads74are male threads. In another case, the inner threads76are male threads and the outer threads74are female threads. In various embodiments, the shape and dimensions (e.g., diameter, length) of the inner periphery70may be configured to secure or protect the second boss58. For example, where the cross-section of the second boss58is a circle, the shape of the inner periphery70may also be circular. In other embodiments the cross-intersection of the second boss58is a rectangle and the shape of the inner periphery70may resemble a rectangle.

As noted above, the fuel tank52can be somewhat expanded when under pressure in part due to the materials used to form the fuel tank52. In some cases, a longer lasting fuel system50results from permitting the fuel tank52to expand while holding the fuel tank52in the fuel system50. In one embodiment, a first bearing block assembly90is provided that is configured to permit some movement between the first boss54and an inner periphery96configured to be disposed around the first boss54. The inner periphery96provides a bearing support space for supporting a bearing which actually contacts the first boss54as discussed further below. The first bearing block assembly90can be configured to be supported in the enclosure53, e.g., being coupled with the mounting brackets51directly or through the frame64.

FIG.3Ashows that the first bearing block assembly90can include a first block portion92A and a second block portion92B. The block portions92A,92B can be separable in a manner similar to the rigid block member68of the fixed bearing block assembly66. The first block portion92A can be lifted off of the second block portion92B to provide access to an inner periphery96of the block portions92A,92B. The inner periphery96can be shaped and sized (e.g., diameter, length) in a variety of different ways. For instance, the inner periphery96can be circular, triangular, rectangular, pentagonal, hexagonal and octagonal. The inner periphery96can be shaped in many other configurations other than those previously listed. A bearing assembly100can be placed in the inner periphery96to provide support for the first boss54. In some embodiments, a second bearing assembly100similar to the first bearing assembly100can be provided on the second boss58. The first bearing assembly100can be secured in the inner periphery96in any suitable manner, such as by being received in a channel therein. In some embodiments, the bearing assembly100can be secured in place by a fastener, pin and key, latch, or other connector. In other embodiments, the bearing assembly can be secured in place through a more permanent method, such as through welding or bonding. In various embodiments, the shape and dimensions (e.g., diameter, length) of the bearing assembly100may be configured to secure to the inner periphery96. For example, where the intersection of the inner periphery96is a circle, the shape of the bearing assembly100may resemble a circle. Where the intersection of the inner periphery96is a rectangle, the shape of the bearing assembly100may resemble a rectangle.

This connection can be more fully appreciated with reference toFIG.4in which the first bearing assembly100is shown positioned over the first boss54. The first bearing assembly100can be seen to have a convex outer surface101. The convex outer surface101can be convex in direction seen in a cross-section transverse, e.g., perpendicular to the opening through the first bearing assembly100, as shown inFIG.7. The convex surface can be received in a corresponding concave channel formed in the inner periphery96of the first bearing block assembly90.FIG.4shows that a first support connection102is provided between the outer surface56of the first boss54and a first inner portion104of the first bearing assembly100.

FIGS.5-7show the first bearing assembly100in more detail. The first bearing assembly100includes an aperture at the first inner portion104. The aperture is sized to receive the outer surface56of the first boss54. The aperture can allow a sliding connection to be formed in the first inner portion104. The first inner portion104can include a first tank support surface108. The first tank support surface108is configured for sliding support of the first boss54of the fuel tank52at an interface there between. The first tank support surface108can be a generally flat surface, e.g., forming a cylindrical portion that can be larger than the outer diameter of the outer surface56of the first boss54. The first tank support surface108can be smooth, with a surface roughness value of anywhere between 0.025 micrometers to 100 micrometers, including about 0.05, 0.1, 0.2, 0.4, 0.8, 1.6, 3.2, 6.3, 12.5, 25, 50, and 100 micrometers. In some embodiments, the first tank support surface108contains bearings, such as a sleeve bearing, ball bearings or another suitable bearing. These bearings can be arranged in a ring or sleeve pattern on the first tank support surface108.

The first tank support surface108can at least, in part, define a space110that is inward of the first tank support surface108. The space110can be disposed between the first tank support surface108and the outer surface56of the first boss54. The space110can be or can include a portion of an interface between the fuel tank52and the first bearing block assembly90. The space110can benefit from the addition of a mechanism to exclude dirt, debris or other matter from the interface. By excluding such matter, the first bearing block assembly90and the fuel system50can have a longer service life, particularly in dirty environments in which heavy duty vehicles are used.

In one embodiment, the first bearing assembly100includes a wiper112. The wiper112can be a first wiper112where the first bearing assembly100also includes a second wiper130. The first wiper112can be an inboard wiper, e.g., one that is positioned between the space110and the cylindrical portion of the fuel tank52. The first wiper112can be an outboard wiper, e.g., one that is positioned such that the block portions92A,92B are disposed between the first wiper112and the cylindrical portion of the fuel tank52. The first wiper112can be outboard in the sense of being more laterally located on the fuel system50.

The first wiper112and/or the second wiper130can be integrated into the first bearing assembly100in convenient manner such that they can be installed together with the first tank support surface108, which is the surface that the outer surface56of the first boss54can rest upon. In one embodiment, the first bearing assembly100includes a ring member100A that extends between the convex outer surface101and the first tank support surface108. The ring member100A can include a continuous monolithic structure from the convex outer surface101to the first tank support surface108. The ring member100A can be formed of a strong, substantially incompressible material. The ring member100A can include a low friction material, at least adjacent to or at the first tank support surface108. Some materials that can form the ring member100A can include, for instance, metal (e.g., aluminum or steel), metal alloy (e.g., aluminum alloys), carbon fiber reinforced plastic, or a plastic material. The ring member100A can be manufactured using a variety of different materials and methods. The ring member100A may be made by any suitable process, such as, for instance, machining, milling, water jet cutting, laser cutting, stamping, pressing, sheet metal drawing, molding (e.g., injection molding), casting, rapid prototyping using additive manufacturing techniques, or any combination thereof. The ring member100A can provide a first recess116disposed on a side surface thereof. The first recess116can be formed in the material of the ring member of the first bearing assembly100between the first tank support surface108and a lateral surface of the ring member100A. A lateral surface in this context can be disposed in a plane perpendicular to an axis A through the first bearing assembly100. The first recess116can correspond to an annular recess disposed between the material forming the first tank support surface108and the lateral edge of the ring member100A of the first bearing assembly100. The first wiper112can be installed in the first recess116.

In one embodiment, the first wiper112has one or more, e.g., two faces that can be secured to the first recess116. Any suitable approach can be provided to secure the first wiper112in the first recess116. For example, an adhesive can be used to secure a first face of the first wiper112to a surface of the first recess116. An adhesive can be used to secure a second face of the first wiper112to a surface of the first recess116. When secured in the first recess116, a free end of the first wiper112can be disposed in an opening through the first bearing assembly100that includes the space110disposed between the first tank support surface108and the axis A. For example, a free end of the first wiper112can be suspended at or adjacent to a lateral face of the ring member100A of the first bearing assembly100. The free end can comprise a free circumferential edge of the first wiper112. The free end of the first wiper112can flare at least partially into the opening within the first bearing assembly100. The free end of the first wiper112can flare toward the axis A and away from the first recess116.

In some embodiments, the first wiper112can be resilient in structure or material. In some embodiments, the first wiper112can be made from a material, including rubber, silicone, metal, cork, neoprene, nitrile rubber, fiberglass, PTFE, plastic, or any combination thereof. The first wiper112can be manufactured by any suitable process, such as, for instance, machining, milling, water jet cutting, laser cutting, stamping, pressing, sheet metal drawing, molding (e.g., injection molding), casting, rapid prototyping using additive manufacturing techniques, or any combination thereof. The first wiper112can be configured such that a portion thereof, e.g., the free end thereof, can be disposed or urged toward the axis A in at least one configuration. The first wiper112can include a rubber ring member120. The rubber material of the rubber ring member120can be springy or resilient such that upon being compressed the first wiper112applies a resisting force against the structure compressing the rubber ring member120. In one case, the rubber ring member120includes an outer periphery122secured in the first recess116and an inner periphery124disposed toward the axis A. The outer periphery122can be disposed in a free state126A toward the axis A by a first amount. The outer periphery122can be disposed in compressed state126B toward the axis A by a second amount. The second amount can be less than the first amount, as shown in, for example,FIG.7A. In some cases, the first wiper112is itself resilient. In other cases, a spring or other resilient member127can be disposed between the ring member of the first bearing assembly100and the first wiper112such that the first wiper112can be stiff but the resilient member127can act to press the first wiper112against the outer surface56of the first boss54.

As discussed above, the first bearing assembly100can include a second wiper130in some cases. If provided, the second wiper130can be of a similar configuration as the first wiper112. The second wiper130can be a mirror image configuration such that an outer periphery122thereof flares toward the axis A. The second wiper130can include or be configured as a rubber ring member. The material of the rubber ring member can be resilient to press against a portion of the outer surface56of the first boss54spaced away from the location of the first wiper112. Thus, a first bearing assembly100with both the first wiper112and the second wiper130can be equipped to exclude matter, e.g., dirt and grit, from the first support connection102, e.g., from the space110forming the interface between the first boss54and the first bearing assembly100. A first bearing assembly100with both the first wiper112and the second wiper130can be equipped to exclude matter from the contact point between the first boss54and the supporting structure of the fuel tank52within the fuel system50.

The first bearing block assembly90provides convenience in assembling the fuel system50including the first bearing block assembly90. For example, the separability of the first block portion92A from the second block portion92B enables the first bearing assembly100to be inserted into the inner periphery96in the space between the block portions92A,92B. When separated, the first and second block portions92A,92B have a “C” shape profile. The “C” shape refers to the first and second block portions92A,92B having a first side facing away from the inner periphery96with a second side and a third side disposed opposite to each other and at opposite ends of the first side, similar to the block members68discussed above. This structure allows the ring member of the first bearing assembly100to be continuous which provides a more rigid structure. A continuous solid structure ring member can be more easily handled and may be more rugged with a longer service life.

FIG.3Bshows another embodiment of a bearing block assembly190that provides other advantages. The assembly ofFIG.3Bcan be the same as the assembly ofFIG.3Aexcept as described differently below. The first bearing block assembly190has a monolithic block component192. The fuel system50can be formed by including the first bearing block assembly190, e.g., by supporting the first bearing block assembly190with the frame64. The block component192can include an outer periphery194coupled to the frame64. The block component192can include an inner periphery196configured to be disposed around the first boss54. The inner periphery196can be sized to surround the outer surface56of the first boss54while also providing a space for a support connection200. The support connection200can include a first inner portion204that can comprise an assembly. The first inner portion204can include a bearing assembly197that can include a ring member199that has a seam198that facilitates placement of the first inner portion204within the inner periphery196. The inner periphery196can include a concave channel that can receive a convex outer surface of the ring member199of the bearing assembly197. The convex outer surface can be similar to the convex outer surface101of the first bearing assembly100. The convex outer surface can be split at least at one location such that the ring member199of the bearing assembly197can be inserted into the inner periphery196. The bearing assembly197can include one or more of the first wiper112and the second wiper130.FIG.3Bshows that ring member199can be coupled with both the first wiper112and the second wiper130.

The integration of the first wiper112and/or the second wiper130into the ring member199of the bearing assembly197can be similar to that of the first bearing assembly100. For example, one or more of the first recess116and the second recess134can be provided in the ring member199. The first wiper112and/or the second wiper130can be coupled with the recesses in a suitable manner, e.g., by an adhesive connection to one or more surfaces of the recesses.

The first bearing block assembly190can be incorporated into fuel system assembly similar to the fuel system50. The continuous uninterrupted configuration of the block component192provides more rigid support for the first boss54in some configurations. Also, the assembly of the fuel system50including the first bearing block assembly190is simplified in not requiring the connection of two separate block components.

In some embodiments, the fuel system50includes a bellows assembly500. A bellows assembly500can include two clamps502and a sheath or cover504. The cover504extends from one clamp502to the other, forming a hollow center506. The clamp502can attach the bellows assembly500to the fuel tank52and the bearing block66,90,190. The clamps502attach the bellows assembly500to the fuel tank52or bearing block66,90,190by exerting a clamping force at a connecting point508. The connecting point508can be a ferrule or lip on the fuel tank52and/or bearing block66,90,190. In some embodiments, there is no connecting point508and the clamps502connect directly to the first or second boss54,58. The bellows assembly500can simultaneously connected to two connecting points508, such as the connecting point508attached to fuel tank52and the connecting point508attached to the bearing block66,90,190. InFIG.8, the cover504covers a section of the first boss54that extends between the fuel tank52and the bearing block66,90,190.

In some embodiments, the bellows assembly500includes two latches instead of two clamps502. In some embodiments, the clamps502are configured as ratcheting members, similar to a hose clamp. In some embodiments, the cover504is made from flexible material, such as natural or synthetic fabric, rubber, silicone, neoprene, nitrile rubber, PTFE, or other plastics. This flexible material allows the cover504to expand or contract, which thus increases or decreases the overall length of the cover504. In some embodiments, the cover504has a ribbed outer surface. The ribbed outer surface allows the hollow center506to maintain about a steady inner circumference while the cover504expands or contracts.

In some embodiments, the fuel system50can include two or more sets of bellows assemblies500, e.g., one for each boss54,58. In some embodiments, the fuel system50can include one of bellow assembly500for a single boss54,58. In some embodiments, the bellows assembly500is used in combination with a bearing block66,90,190.

FIGS.10-12Cshow another embodiment of a bearing block assembly600for use with the fuel system50. The bearing block assembly600can be similar to the bearing block assemblies described elsewhere herein, the disclosure of which can supplement the disclosure hereinbelow. The disclosure of the bearing block assembly600can supplement the other bearing block assemblies described herein. The bearing block assembly600can permit some movement between the first boss54and the bearing block assembly600, while also reducing the ingress of debris onto the first boss54. The bearing block assembly600can exclude ingress of debris from one or both of an outboard and an inboard side. The bearing block assembly can include an inner periphery620, which can be disposed around the first boss54. The inner periphery620provides a bearing support space for supporting the first bearing assembly100, which actually contacts the first boss54. As discussed above, the first bearing assembly100includes one or more dust wipers. In variations more or fewer wipers can be provided. In one embodiment the bearing block assembly600can be provided without any dust wipers in the interface between the boss54and the bearing surface of the assembly100, as shown inFIG.11. The bearing block assembly600can be supported in the enclosure53. For example, the bearing block assembly600can be coupled with the mounting brackets51directly or through the frame64.

As shown inFIGS.10and11, the bearing block assembly600can include a bearing block602.FIGS.12A-12Cshow that the bearing block602can include a first block portion602A and a second block portion602B. The block portions602A,602B can be separable in a manner similar to the rigid block member68of the fixed bearing block assembly66and the first bearing block92of first bearing block assembly90. The first block portion602A can be lifted off of or separated from the second block portion602B to provide access to an inner periphery620of the block portions602A,602B. The inner periphery620can be shaped and sized (e.g., diameter, length) in a variety of different ways. For instance, the inner periphery620can be circular, triangular, rectangular, pentagonal, hexagonal and octagonal. The inner periphery620can be shaped in many other configurations other than those previously listed. A bearing assembly100can be placed in the inner periphery620to provide support for the first boss54. The bearing assembly100can be secured in the inner periphery620in any suitable manner, such as by being received in a channel therein. In some embodiments, the bearing assembly100can be secured in place by a fastener, pin and key, latch, or other connector. In other embodiments, the bearing assembly can be secured in place through a more permanent method, such as through welding or bonding. In various embodiments, the shape and dimensions (e.g., diameter, length) of the bearing assembly100may be configured to secure to the inner periphery602. For example, where the intersection of the inner periphery620is a circle, the shape of the bearing assembly100may resemble a circle. Where the intersection of the inner periphery602is a rectangle, the shape of the outer periphery of the bearing assembly100may resemble a rectangle.

The bearing block602can include a ridge622. The ridge622can be formed on one or two sides of the first block portion602A and the second block portion602B. The ridge622can form a raised surface on a side of the bearing block602. The ridge622can be used to connect the bearing block602to a structure or can be used to secure a structure to the bearing block602. For example, a clamp608can be placed around the outer edge of the ridge622to hold a cover606in place. The ridge622can include an annular projection on a first or inboard side of the bearing block620. The ridge622can provide a peripheral, e.g., a circumferential, surface623providing an area upon which a clamp can apply a compression force. Although the peripheral surface623is illustrated as flat, a concave recess can be provided in the peripheral surface623to receive or partly receive a portion of a clamp.

The bearing block602can include one or more fastener holes626. The fastener holes626can be formed on one or more sides of the first block portion602A and the second block portion602B. The fastener holes626can be disposed on an outboard side, as shown. In some embodiments, fastener holes626can be disposed on inboard and outboard sides of the bearing block portions602A,602B. In some embodiments, the fastener holes626are through holes that extend through the block portions602A,602B. In other embodiments, the fastener holes626do not extend completely through the block portions602A,602B. The fastener holes626can be used to connect the bearing block602to a structure or can be used to secure a structure to the bearing block602. For example, the fastener holes626can receive fasteners612to secure the end cap604to the bearing block602. The fastener holes626can be used to secure the cover606in some embodiments.

The bearing block602can include through holes624. The through holes624can be formed on one side of the first block portion602A and the second block portion602B. The through holes624can be used connect the bearing block602to a structure. For example, the through holes624can be used connect the bearing block602to the mounting brackets51directly or the frame64.

The bearing block602provides convenience in assembling the fuel system50including the bearing block assembly600. For example, the separability of the first block portion602A from the second block portion602B enables the first bearing assembly100to be inserted into the inner periphery620in the space between the block portions602A,602B. When separated, the first and second block portions602A,602B can have a “C” shape profile. The “C” shape refers to the first and second block portions602A,602B having a first side facing away from the inner periphery620A with a second side and a third side disposed opposite to each other and at opposite ends of the first side, similar to the block members68and92discussed above. This structure allows a ring member or other portion or all of the first bearing assembly100to be continuous which provides a more rigid structure. A continuous solid structure ring member can be more easily handled and may be more rugged with a longer service life.

FIGS.10and11show further details of the endcap604and the integration thereof into the bearing block assembly600. The end cap604can have a cylindrical shape with an open-ended chamber. The end cap604can have an opening on one side of the end cap604that leads to the chamber. This open-ended chamber allows for the end cap604to be placed around objects. For example, the end cap604can be placed around the first boss54. This open-ended chamber can have a closed end at an inside surface607opposite to the opening to mitigate or exclude dust or debris from entering the space in the chamber. The end cap604can have one or more fastener holes, which allow for the end cap604to connect to a structure or can be used to secure a structure to the end cap604. For example, the end cap604can be fastened to a side of the bearing block602. The fastener holes can be disposed on a radially outwardly extending annular flange605. An inboard side of the flange605can make contact with outside surfaces of the block portions602A,602B.

As shown inFIGS.10and11, the bearing block assembly600can include a cover606. The cover606can be a material that can be placed over other components. In some embodiments, the cover606can have a hollowed center, which allows for the cover606to be slid over other components. For example, the cover606can be slid or placed over the first boss54. The cover606can be made from a flexible material, such as natural or synthetic fabric, rubber, silicone, neoprene, nitrile rubber, PTFE, or other plastics. This flexible material allows the cover606to expand or contract, which thus increases or decreases the overall length of the cover606. The cover606can be connected to other components through a clamp608. For example, the cover606can be connected to the bearing block602and the first boss54of the fuel tank52with two clamps608. For example, a first clamp608can be disposed on the bearing block602, e.g., by compression onto the peripheral surface623, and a second clamp608can be disposed on a surface625of the first boss54. The first and second clamps608can have the same configuration, e.g., similar to hose clamps in one embodiment.

The bearing block assembly600can be used to prevent the ingress of dust and other debris into the inner periphery620and the first boss54. As shown inFIGS.10and11, the bearing block602, end cap604, and cover606can be used to envelop most of, or all of, the outer surface56of the first boss54. For example, the cover606can be used for coverage of the first boss54between the connecting point508of the fuel tank and the connecting point to bearing block602, while the end cap can be used to for coverage of the first boss54between the bearing block602and the end of the first boss54. As a result of this coverage, the bearing block assembly600can greatly limit the amount of debris that can enter into the inner periphery620. This coverage can also keep the outer surface56of the first boss54free from debris. The use of wipers112in the interface between the bearing block602and the boss54can further exclude debris from this interface.

As noted above, the bearing block assembly600can permit some movement between the bearing block assembly600and the first boss54. The fuel tank52can be somewhat expanded, e.g., elongated, when under pressure in part due to the materials used to form the fuel tank52. As the fuel tank52expands or contracts, the first bearing assembly100disposed within the bearing block assembly600can allow for first boss54to move relative thereto. The cover606can expand, e.g., elongate, or contract, e.g., foreshorten, along with the fuel tank52, which allows for cover606to maintain its coverage over the first boss54. The cover606can include a bellows-type member, as discussed above in connection withFIGS.8-9or can comprise a material or structure that permits elastic expansion and/or contraction. The chamber of the endcap604can be sized so as to allow for the fuel tank52to expand without the inside surface607of the endcap contacting the first boss54. For example, the inside surface607of the endcap604can be spaced away from the end of the first boss54or a plug610enclosing an access passage in the boss54at or beyond the expected travel distance of the first boss54or plug610. Thus, the bearing block assembly600can maintain its coverage of the first boss54while the fuel tank52expands or contracts without interfering with the expected expansion and contraction of the boss54and/or the plug610.

Fuel System with Sacrificial Neck Sleeve

During use, the boss of a fuel tank can experience wear due to pressurization, vibration, debris, and/or misalignment when the fuel tank is neck-mounted within a fuel system. For example, the outer surface of the boss can chafe against a mounting bracket supporting the boss. Damage to the boss of a fuel tank can make it necessary to repair or replace the fuel tank or portions of the fuel tank. Providing a wear surface that is separable from the fuel tank, such as a sacrificial neck sleeve, would advantageously reduce or prevent damage to the fuel tank (e.g., to the boss of the fuel tank). Further, such a wear surface could be removed and replaced more easily and inexpensively than could a fuel tank.

FIG.13shows another embodiment of a fuel system50′. The fuel system50′ can be similar to the fuel system50described elsewhere herein, the disclosure of which can supplement the disclosure below. The disclosure of the fuel system50′ can supplement the other fuel systems described herein. The fuel system50′ can be mountable on a heavy-duty vehicle, such as a tractor-trailer. The fuel system50′ can include one or more fuel tank(s)52, a mounting assembly700, and a frame702. Each fuel tank52can include a central portion (e.g., a central cylindrical portion) and an end assembly. The central portion of the fuel tank52can include a carbon fiber reinforced polymeric liner. The end assembly of the fuel tank52can include a dome portion and a metallic boss, where the dome portion extends between the central cylindrical portion and the metallic boss. In some embodiments, the carbon reinforcement can extend over the polymeric liner and over at least a portion of the dome portion. The mounting assembly700can include, or be supported by, the frame702. The mounting assembly700can include, or be coupled to, a block member(s) that receives one or more bosses54,58of the fuel tank52(the first boss54and the second boss58are shown schematically inFIG.2A). Each boss54,58can include a mounting surface (e.g., an outer surface).

The mounting assembly700can be configured for mounting to a rooftop of a vehicle. For example, longitudinal members703A of the frame702can extend along one or more tank(s)52. The longitudinal members703A can be configured with connection brackets or members for securing the mounting assembly700to an upper chassis portion of a vehicle forming a structure of a rooftop of the vehicle. Transverse members703B can be provided to connect two or more longitudinal members703A. The length of and spacing between the longitudinal members703A can correspond to the location of connection points of the vehicle chassis. The length of and spacing between the transverse members703B can correspond to the location of connection points of the vehicle chassis. The frame702can be configured to support tanks52that are horizontally aligned, e.g., such that central longitudinal axes of the tanks52are disposed in a horizontal plane. The frame702can be configured to support tanks52that are vertically offset, e.g., such that central longitudinal axes of the tanks52are disposed in different horizontal planes. The frame702can support other structures, such as platforms to support other loads, including cargo and service personnel. Though not shown, the fuel system50′ will be understood to also include tubing to convey the fuel from within the tank(s)52to a combustion engine, fuel cell or other load drawing from the fuel system50′.

As illustrated inFIG.13and shown in greater detail inFIGS.14A-14C and16, another embodiment of a bearing block assembly710(e.g., bearing block assembly, mounting block assembly, bearing block, mounting block, mounting member, mounting portion, and/or the like) can be used with the fuel system50′. The bearing block assembly710can be similar to the bearing block assemblies described elsewhere herein, the disclosure of which can supplement the disclosure below. The disclosure of the bearing block assembly710can supplement the other bearing block assemblies described herein. For example, the sacrificial sleeves described herein can be used with any of the tanks and/or bearing or mounting assemblies disclosed herein, and any portion of the bearing or mounting assemblies disclosed herein can be used with the assemblies described and shown as including a sleeve. The bearing block assembly710can permit some movement between the first boss54and the bearing block assembly710. The bearing block assembly710can include a bearing block712with an inner periphery714and an outer periphery716. In some embodiments, the inner periphery714provides a bearing support space for supporting a bearing (e.g., a bearing having a spherical outer surface, such as is illustrated inFIGS.4-7), where the bearing is configured to contact a sleeve750that is disposed around the first boss54. In some embodiments, the inner periphery714provides a support space having or disposed within a support surface (e.g., a tank component support surface) that is configured to directly contact a sleeve750that is disposed around the first boss54. The support space can support a portion of the sleeve750over the boss54. The sleeve750can be made of any material that provides a wear surface for the boss54. In some embodiments, the support space (e.g., support surface) of the inner periphery714(and/or the entire mounting block portions712A,712B) can be made of a more wear-resistant (e.g., harder) material than the sleeve750. In some embodiments, the mounting block comprises a homogenous material from an inner periphery714to an outer periphery716of the block712. In some embodiments, the sleeve750comprises a homogenous material from an inner periphery752to an outer periphery754of the sleeve750. In some embodiments, the bearing block712comprises aluminum and the sleeve750comprises a thermoplastic material (such as an acetal or other polymer). In some embodiments, the sleeve750comprises a self-lubricating polymer, such as an acetal copolymer or homopolymer. In some embodiments, the sleeve750comprises a polymer (such as a thermoplastic polymer, acetal, nylon, and/or the like) and the bearing block712comprises a metal (such as aluminum, steel, titanium, and/or the like). In some embodiments, the block712comprises A380 Aluminum. In some embodiments, the block712has a hardness of 80 HB. In some embodiments, the block712is anodized (e.g., with a surface finish on the support surface of 32 RMS). In some embodiments, the sleeve750comprises Delrin. In some embodiments, the sleeve750has a hardness of Rockwell R120. In some embodiments, the sleeve750further comprises a material that is less wear-resistant than the material of the boss54. This can be desirable particularly in a situation where the sleeve750may be at least somewhat restrained from longitudinal and/or rotational motion with respect to the boss54, but where at least some small relative motion may occur during use, such as through vibration, thermal changes, and/or the like.

As shown inFIGS.14A-14C, the bearing block712can include a first block portion712A and a second block portion712B. The block portions712A,712B can be separable in a manner similar to the bearing block602of the bearing block assembly600, the rigid block member68of the fixed bearing block assembly66, and the first bearing block92of first bearing block assembly90. As illustrated inFIG.14B, the first block portion712A can be lifted off of or separated from the second block portion712B to provide access to the support surface of the inner periphery714of the bearing block712(e.g., the support surface of the inner peripheries of the block portions712A,712B). The inner periphery714can be shaped and sized (e.g., diameter, length) in a variety of different ways. For instance, the inner periphery714can be circular, triangular, rectangular, pentagonal, hexagonal and octagonal. The inner periphery714can be shaped in many other configurations other than those previously listed. In some embodiments, a bearing assembly can be placed in the inner periphery714. Further, some embodiments may form the inner periphery714using a single member or block, instead of having one block portion be separable from another block portion. In such a design, the fuel tank boss54may be installed by, for example, sliding the boss54into the mounting block712, sliding the mounting block712over the boss54, and/or the like.

As shown inFIG.14C, the bearing block712can include a first edge718A on a first end and a second edge718B on a second end opposite the first end. As illustrated inFIGS.14C and16, the interface between the first edge718A and the inner periphery714can include a rounded portion (e.g., a curved surface, a convex surface, a radiused edge, and/or the like). The interface between the second edge718B and the inner periphery714can include a rounded portion (e.g., a curved surface, a convex surface, a radiused edge, and/or the like). The curved surface(s) can advantageously reduce stress and/or wear on the sleeve750resulting from any lateral load on the sleeve750as the sleeve750slides longitudinally with respect to the mounting block710and/or any angular misalignment of the boss54and/or bearing block712when the sleeve750is disposed within the space formed by the inner periphery714of the bearing block712.

FIG.2Aillustrates an exaggerated example of such angular misalignment, using angle1401. In some embodiments, it may be desirable for the mounting blocks at both ends of the tank (e.g., elements66and90ofFIG.2A), to include radiused edges718A and718B. In some embodiments, only the mounting block that interfaces with the sleeve750comprises such radiused edges. In some embodiments, the radiused edges718A and/or718B comprise a radius that is at least 5% of an outer diameter of the sleeve750(e.g., a diameter of the outer periphery754of the sleeve750) and/or of an inner diameter of the mounting block (e.g., the inner periphery714of the bearing block assembly710). In some embodiments, the radiused edges718A and/or718B comprise a radius that is at least 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, or 10% of an outer diameter of the sleeve750(e.g., a diameter of the outer periphery754of the sleeve750) and/or of an inner diameter of the mounting block (e.g., the inner periphery714of the bearing block assembly710).

In some embodiments, the sleeve750may be used in combination with a mounting block assembly that includes a separate component that helps to account for or limit wear on the sleeve due to angular misalignment. For example, the sleeve750may be used in combination with a bearing assembly, such as bearing assembly100ofFIG.4, which includes a convex outer surface101that fits into a corresponding concave surface of the mounting block in order to help account for angular misalignment. In some embodiments, however, the sleeve750may be configured to be in direct contact with, or to be directly supported by, the inner surface of a mounting block or mounting block assembly (such as inner surface714ofFIG.14C), with no additional bearing or other component therebetween. For example, in some embodiments there is no bearing, bushing, and/or the like between the sleeve750and the mounting block or mounting block assembly (such as inner surface714of the bearing block712). Radiused edges718A and/or718B can be particularly beneficial in such embodiments. The sleeve750may also be used in combination with any wipers disclosed herein, such as to limit introduction of debris while at the same time providing the sacrificial surface on the sleeve750to absorb any wear from debris or otherwise.

The bearing block712can include a plurality of apertures720configured to receive fasteners722. The apertures720can extend through the entire height of the bearing block712(e.g. in a direction perpendicular to the longitudinal length of the fuel tank52, through the outer periphery716on the upper portion of the bearing block712and beyond the outer periphery716on the lower portion of the bearing block). The apertures720can extend through the first block portion712A and the second block portion712B. A fastener722can be inserted into each aperture720, through the bearing block712(e.g., through the first block portion712A and the second block portion712B), and into openings in the mounting assembly700. This arrangement can advantageously allow the first and second block portions712A,712B to be secured in position relative to one another and can allow the bearing block712to be secured to the mounting assembly700.

In some embodiments, as shown inFIGS.14A and14B, a plug704can be used with the fuel system50′. The plug704can be similar to the plug610described elsewhere herein, the disclosure of which can supplement the disclosure hereinbelow. The plug704can be configured to enclose an access passage in the first boss54at or beyond the expected travel distance of the first boss54or plug704. In some embodiments, as illustrated inFIG.14B, the plug704includes a threaded portion that is compatible with a corresponding portion of the access passage in the first boss54. In some embodiments, as shown inFIG.14B, an O-ring706is positioned between the plug704and the first boss54to improve the seal between the plug704and the access passage of the first boss54.

As shown inFIGS.14A-16, a sleeve750can be used with the fuel system50′. The sleeve750can be a sacrificial component configured to protect the boss54of the fuel tank52from damage. The sleeve750can be configured to be disposed around the boss54. The sleeve750can be removably coupled to the boss54. The sleeve750can be replaceable. A damaged sleeve750can be easier and/or cheaper to replace than a damaged fuel tank52. In some embodiments, it may be possible to replace the sleeve750without removing the fuel tank52from the mounting block712. In some embodiments, such as when the mounting block712is a single piece or multiple pieces, the sleeve750may be removable and/or replaceable without removing the fuel tank52from the mounting block712, by removing the retaining ring760and sliding the sleeve750off of the boss54while the mounting block712remains in place. In some embodiments, such as when the mounting block712is part of a mounting block assembly710having more than one mounting block component, one of the first and second portion of the mounting block assembly710may be separated from the other of the first and second portion to provide easier access to the sleeve750for purposes of removal of the sleeve. In some embodiments, the tank52may be moved a small distance longitudinally and/or laterally away from the mounting block712to facilitate removal and/or replacement of the sleeve750. Additionally, the inclusion of a sleeve750can make it easier to identify signs of wear. For example, signs of wear can include the presence of plastic shavings, an inconsistent gap between the mounting block and the sleeve, and/or variations in the diameter of the sleeve.

The sleeve750can have a first end750A, a second end750B opposite the first end750A, an inner periphery752, and an outer periphery754. In some embodiments, the sleeve750can have a thickness of approximately 0.125 in (measured as the wall thickness between inner periphery752and outer periphery754). In some embodiments, the sleeve750can have a thickness of at least 0.05 in, 0.075 in, 0.10 in, 0.125 in, 0.15 in, 0.175 in, 0.2 in, 0.225 in, or 0.25 in. In some embodiments, the sleeve750can have a length of approximately 3 in. In some embodiments, the sleeve750can have a length of at least 1 in, 1.5 in, 2 in, 2.5 in, 3 in, 3.5 in, 4 in, 4.5 in, 5 in, 5.5 in, or 6 in.

The inner periphery752of the sleeve750can be coupled to a mounting surface (e.g., outer surface) of the boss54such that the sleeve750is restrained longitudinally relative to the boss54and configured to slide longitudinally relative to the support surface of the inner periphery714of the bearing block assembly710(e.g., the inner periphery of the bearing block712) upon expansion of the fuel tank52when the fuel tank52is pressurized. The first end750A can be configured to be positioned adjacent to a dome portion of the fuel tank52when the sleeve750is disposed around the boss54. The second end750B can be configured to be positioned adjacent to an outer end of the boss54when the sleeve750is disposed around the boss54. The sleeve750can have a cylindrical shape. The sleeve750can have an interruption in the circumference of the sleeve, such as a slit, gap, seam, or opening. For example, a slit756can extend between opposing ends of the sleeve750. The slit756can extend through the outer periphery754and the inner periphery752along a portion of the sleeve750. The slit756can advantageously allow for less precise tolerances between the diameter of the sleeve750and the outer diameter of the boss54. The diameter of the sleeve750can be undersized relative to the mounting surface of the boss54to enable a tight fit between the sleeve750and boss54. Therefore, the sleeve750can be used on the boss54even if the diameter of the sleeve750is smaller than or equal to the outer diameter of the boss54. In some embodiments, the sleeve750can compress around the boss54when the slit756is expanded (such as, for example, due to the elasticity of the material of the sleeve750).

In some embodiments, the outer circumference of the sleeve750is uninterrupted. For example, in some embodiments, the sleeve750does not include a slit, gap, seam, opening, and/or the like.

A first surface or edge758A on the first end750A of the sleeve750can have different characteristics than a second surface or edge758B on the second end750B of the sleeve750. For example, as shown inFIGS.14B,14C, and15, the first edge758A can be chamfered and the second edge758B can be less chamfered (e.g., having a smaller chamfer) than the first edge or non-chamfered (e.g., not having a chamfer, having an edge break, or being flat). The chamfered first edge758A can be positioned adjacent to the end of the boss54that is closest to the dome portion of the fuel tank52when the sleeve750is disposed around the boss54. The chamfer can advantageously allow the sleeve750to fit on a boss54with a blend radius. The less or non-chamfered second edge758B can be positioned adjacent to the end of the boss54that is further from the dome portion of the fuel tank52when the sleeve750is disposed around the boss54. The less or non-chamfered second edge758B can be configured to abut a retaining ring760. The less or non-chamfered (or at least less-chamfered) second edge785B can be desirable, for example, to provide a larger surface area to abut a retention member, such as retainer ring760or the like.

In some embodiments, a size of the chamfer at first edge758A, measured radially from inner periphery752to the outermost edge of the chamfer, is at least 5 times a size of any chamfer or edge break at the second edge758B. In some embodiments, the size of the chamfer at first edge758A, measured radially from inner periphery752to the outermost edge of the chamfer, is at least 3, 4, 5, 6, 7, 8, 9, or 10 times the size of any chamfer or edge break at the second edge758B. In some embodiments, the size of the chamfer at first edge758A, measured radially from inner periphery752to the outermost edge of the chamfer, is at least 75% of a thickness of the wall of the sleeve750(measured from inner periphery752to outer periphery754). In some embodiments, the size of the chamfer at first edge758A, measured radially from inner periphery752to the outermost edge of the chamfer, is at least 50%, 60%, 70%, 75%, 80%, or 90% of the thickness of the wall of the sleeve750(measured from inner periphery752to outer periphery754).

The sleeve750can be secured in position with respect to the boss54using a retaining portion, such as a retaining ring760, threads, adhesive, and/or an interference fit. The outer shape of the retaining ring760can be circular or any other shape. For example, the outer shape can be hexagon or square. In some embodiments, the retaining portion can be a ring761and set screw762, as shown inFIG.14D. The ring761and set screw762can include a keyway763. The retaining portion can be configured to removably secure the sleeve750to the boss54so that the sleeve750does not unintentionally slide off of the boss54. In some embodiments, the sleeve750can be restrained relative to the boss54(e.g., there is limited movement allowed between the sleeve750and the boss54). For example, in some embodiments, the sleeve750is not movable longitudinally by more than 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, or 6% of the length of the sleeve750. In some embodiments, the sleeve750can be fixed relative to the boss54(e.g., there is no movement allowed between the sleeve750and the boss54). For example, in some embodiments, the sleeve750is not movable longitudinally with respect to the boss54. As shown inFIG.16, the retaining portion can include a retaining ring760configured to be positioned between an outer edge of the sleeve750(e.g., the second edge758B at the second end750B of the sleeve750) and a lip770at the end of the boss54(e.g., the end of the boss54furthest from the dome portion of the fuel tank52and closest to the second end750B of the sleeve750when the sleeve750is disposed around the boss54). The outer edge of the sleeve750can be an outboard edge in the case of a fuel system50that is mounted transversely relative to a vehicle and can be a forward or rearward edge in the case of a fuel system50′ that is mounted longitudinally relative to a vehicle. In some embodiments, a portion of the retaining ring760is positioned within a groove in the outer surface of the boss54, which positions the retaining ring760longitudinally between the edge758B of the sleeve750and the lip770of the boss54. In some embodiments, a spring or other compressible member (e.g., a disc spring, wave spring, o-ring, gasket, and/or the like) can be positioned between the retaining ring760and the sleeve750(and/or between the sleeve750and the boss54, between the retaining ring760and the lip770, and/or the like) to take up any tolerances between the sleeve750and the ring760, thereby preventing the sleeve750from freely moving longitudinally. In some embodiments, the length of the sleeve750and the position of the groove that retains the retaining ring760are dimensioned such that there is relatively little clearance between the retaining ring760and the sleeve750in the installed position. In some embodiments, the length of the sleeve750and the position of the groove that retains the retaining ring760are dimensioned such that there is an interference fit between the retaining ring760and the sleeve750in the installed position. The retaining ring760can be a C-shaped ring, or can be any other suitable shape of retaining ring (e.g., a spiral retaining ring, a tapered section retaining ring, a constant section retaining ring, a circlip, and/or the like). The retaining ring760can include a gap between a first end and a second end of the ring760. In some embodiments, the inner surface of the sleeve750and the outer surface of the boss54may comprise one or more anti-rotation features, such as a spline, a keyway, a protrusion, an interlocking feature, and/or the like, that limits or prevents relative rotation between the sleeve750and the boss54.

The retaining ring760can be removable and/or replaceable. The retaining ring760can be removed from the fuel system50′ to facilitate removal of the sleeve750from the fuel system50′. For example, after the retaining ring760has been removed, the sleeve750can be slid off of the boss54.

The bearing block712can be disposed around a portion of the sleeve750when the sleeve750is disposed around the boss54. The inner periphery714of the bearing block712can contact a portion of the outer periphery754of the sleeve750. The length of the sleeve750can be greater than the length of the bearing block712(e.g., the length of the inner periphery714). This can be desirable, for example, to account for tolerances in installation and/or to allow for sliding of the sleeve750with respect to the bearing or mounting block712during use. For example, the length of the sleeve750can be about 2-8 times greater than the length of the bearing block712(e.g., the length of the inner periphery714). In some embodiments, the length of the sleeve is at least 1.5, 2, 3, 4, 5, 6, 7, 8, 9, or 10 times greater than the length of the bearing block712(e.g., the length of the inner periphery714).

The bearing block712can include a one piece block, e.g., similar to the bearing block assembly190. The slidability of the sleeve750relative to the bearing block712facilitates assembly of the boss54and sleeve750in the block712. By enabling the sliding of the sleeve750and boss54into the block712the assembly thereof is made much simpler. Also, the assembly has fewer components.

The bearing block712can include a multiple piece block, e.g., a two piece block similar to the bearing block assembly710. The two piece bock assembly710allows the sleeve750to be placed on a partial support surface disposed on one of the mounting block portions712A,712B. Thereafter the other of the mounting block portions712A,712B can be assembled over the sleeve750to enclose the sleeve in a support surface.

In some embodiments, a method of using, installing, removing, and/or replacing a sleeve750from a neck (e.g., boss) of a fuel tank52is provided. In some embodiments, an inner surface752of the sleeve750may be touching the outer surface of the boss54. In some embodiments, the outer surface754of the sleeve750may be exposed to be placed in direct contact with a bearing block support surface. In some embodiments, the sleeve750may be elastically flexible to be opened at the seam756. In some embodiments, the seam756may be stretched, expanded, and/or the like transverse to the longitudinal axis of the boss54, such that the inner surface752is larger than the diameter of the boss54to enable applying the sleeve750to the boss54. In some embodiments, the sleeve750may be installable and/or removable from the boss54by sliding the sleeve750longitudinally on and/or off of the boss54. In some embodiments, the method of replacing a sleeve750can comprise removing a retaining ring760(e.g., by longitudinally separating the ring760from the sleeve750and/or the boss54), removing a first sleeve750from the boss54(e.g., by sliding the sleeve750longitudinally of off the boss54), sliding a second sleeve750onto the boss54(e.g., by sliding the sleeve750longitudinally onto the boss54), and re-attaching the retaining ring760(or a new retaining ring) (e.g., by coupling the retaining ring760to the sleeve750and/or the boss54). In some embodiments, the method further comprises removing a plug704from a channel of the boss54and/or removing an o-ring706between the plug704and the boss54(seeFIG.14B). Removing the first sleeve750from the boss54can include stretching the sleeve750along the seam756to temporarily create a gap between the outer diameter of the boss54and the inner diameter of the sleeve750. Placing the second sleeve750on the boss54can include stretching the sleeve750along the seam756to temporarily create a gap between the outer diameter of the boss54and the inner diameter of the sleeve750. In some embodiments, a chamfer, rounded surface, tapered surface, and/or the like of the sleeve (such as the chamfered first edge758A of the sleeve750) can be used to expand or stretch the sleeve as the sleeve begins to be pressed longitudinally onto the boss54. In some embodiments, the boss54may also or alternatively comprise a chamfer, rounded surface, tapered surface, and/or the like that helps to expand or stretch the sleeve as the sleeve begins to be pressed longitudinally onto the boss54.

While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the disclosure. Indeed, the novel methods and systems described herein may be embodied in a variety of other forms. Furthermore, various omissions, substitutions and changes in the systems and methods described herein may be made without departing from the spirit of the disclosure. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the disclosure. Accordingly, the scope of the present inventions is defined only by reference to the appended claims.

Features, materials, characteristics, or groups described in conjunction with a particular aspect, embodiment, or example are to be understood to be applicable to any other aspect, embodiment or example described in this section or elsewhere in this specification unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. The protection is not restricted to the details of any foregoing embodiments. The protection extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Furthermore, certain features that are described in this disclosure in the context of separate implementations can also be implemented in combination in a single implementation. Conversely, various features that are described in the context of a single implementation can also be implemented in multiple implementations separately or in any suitable subcombination. Moreover, although features may be described above as acting in certain combinations, one or more features from a claimed combination can, in some cases, be excised from the combination, and the combination may be claimed as a subcombination or variation of a subcombination.

Moreover, while operations may be depicted in the drawings or described in the specification in a particular order, such operations need not be performed in the particular order shown or in sequential order, or that all operations be performed, to achieve desirable results. Other operations that are not depicted or described can be incorporated in the example methods and processes. For example, one or more additional operations can be performed before, after, simultaneously, or between any of the described operations. Further, the operations may be rearranged or reordered in other implementations. Those skilled in the art will appreciate that in some embodiments, the actual steps taken in the processes illustrated and/or disclosed may differ from those shown in the figures. Depending on the embodiment, certain of the steps described above may be removed, others may be added. Furthermore, the features and attributes of the specific embodiments disclosed above may be combined in different ways to form additional embodiments, all of which fall within the scope of the present disclosure. Also, the separation of various system components in the implementations described above should not be understood as requiring such separation in all implementations, and it should be understood that the described components and systems can generally be integrated together in a single product or packaged into multiple products.

For purposes of this disclosure, certain aspects, advantages, and novel features are described herein. Not necessarily all such advantages may be achieved in accordance with any particular embodiment. Thus, for example, those skilled in the art will recognize that the disclosure may be embodied or carried out in a manner that achieves one advantage or a group of advantages as taught herein without necessarily achieving other advantages as may be taught or suggested herein.

Conditional language, such as “can,” “could,” “might,” or “may,” unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements, and/or steps. Thus, such conditional language is not generally intended to imply that features, elements, and/or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without user input or prompting, whether these features, elements, and/or steps are included or are to be performed in any particular embodiment.

Conjunctive language such as the phrase “at least one of X, Y, and Z,” unless specifically stated otherwise, is otherwise understood with the context as used in general to convey that an item, term, etc. may be either X, Y, or Z. Thus, such conjunctive language is not generally intended to imply that certain embodiments require the presence of at least one of X, at least one of Y, and at least one of Z.

Language of degree used herein, such as the terms “approximately,” “about,” “generally,” and “substantially” as used herein represent a value, amount, or characteristic close to the stated value, amount, or characteristic that still performs a desired function or achieves a desired result. For example, the terms “approximately”, “about”, “generally,” and “substantially” may refer to an amount that is within less than 10% of, within less than 5% of, within less than 1% of, within less than 0.1% of, and within less than 0.01% of the stated amount. As another example, in certain embodiments, the terms “generally parallel” and “substantially parallel” refer to a value, amount, or characteristic that departs from exactly parallel by less than or equal to 15 degrees, 10 degrees, 5 degrees, 3 degrees, 1 degree, or 0.1 degree.

The scope of the present disclosure is not intended to be limited by the specific disclosures of preferred embodiments in this section or elsewhere in this specification, and may be defined by claims as presented in this section or elsewhere in this specification or as presented in the future. The language of the claims is to be interpreted broadly based on the language employed in the claims and not limited to the examples described in the present specification or during the prosecution of the application, which examples are to be construed as non-exclusive.