Not applicable.
Field of the Disclosure
Embodiments disclosed herein generally relate to an apparatus for creating a traversable path over a surface. Specific embodiments relate to a portable apparatus configured to conform to a surface with one or more varying contours, and methods and systems for the same. Other embodiments relate to a portable apparatus having independently adjustable steps movingly connected to a frame member.
Background
There are many different types of ladders and stairways presently used for residential, recreational, or industrial purposes, such as a conventional folding stepladder or a rope ladder, with some of these ladders also having adjustable steps. Some stairways are heavy-duty and/or well-built in order to provide a maximum level of durability or safety. Heavier stairways, usually comprising reinforced concrete or large metal grid-like structures, are used in construction or industry and are intended as permanent, long-life climbable structures. These stairways are quite heavy, cost-prohibitive, and the manufacture, transportation, and/or installation of such stairways are extremely difficult tasks. Because these stairways are rigid, one-piece, and difficult to move, there is no practicability in moving them once they are positioned in place. As such, these stairways also lack flexibility. Other stairways, or even walkways, are lighter and portable in order to provide some flexibility, but these are weak or flimsy, and also susceptible to damage from the surrounding environment.
One industry where stairways are used routinely is the petrochemical industry. Conventional stairways, ladders, walkways, etc. are used en mass in, for example, a petrochemical plant 103. The petrochemical plant 103, partially illustrated in
These storage tanks are often fitted with one or more nozzles, valves, etc., which are subsequently connected with associated piping (as needed) so that the fluids are transferable in and out of the tank 105. Because the storage tanks have these openings, the tanks 105 are susceptible to leaking. As such, there are typically rules and regulations established by governing bodies (e.g., OSHA) that require safety systems to be put in place around tanks or tank farms in case there is a leak. One way to ensure safety in the event of a leak is to construct a barrier 124 that surrounds the tank 105 in entirety, which usually entails the barrier 124 establishing a leak-proof perimeter around the tank farm 155.
Accordingly, climbable structures, such as hardened stairway 101, are fitted to or over the barrier 124 so that the tank farm 155 may be accessed. The problem with hardened stairway 101 is that stairways of this nature are fixed in place. In addition, stairways like this are expensive to manufacture and install so there is usually only a single stairway placed onto the barrier 124. Because the tank farm 155 is only meant to be accessible via the stairway 101, the user 111 must walk all the way over to the stairway 101, which is highly inconvenient and time consuming.
A pathway to get from point A to point B shown in
While this is an inconvenience in itself for the barriers 124 and 124B, it is even more problematic for climbable structures that are not intended for climbing, such as barrier 124C illustrated in
A similar effect may be found in areas, such as coastlines, beaches, or other land areas immediately adjacent a body of water 170, where sand dunes 124D or man-made berms are created to protect inland shorelines and structures, as illustrated in
However, like the barrier 124C previously described, beach goers and users 111 become complacent as a result of the inconvenience caused by sporadic placement of stairways 101D over vast distances, and will instead start making paths along the dunes, berms, etc. themselves. The continual treading on the dunes and berms eventually wears them away, leading to a breach 125 that becomes severely problematic when high tides or flooding waters occur.
There are other areas where a user or operator has need to traverse or walk on contoured surfaces, such as rooftop 117. As shown in
As a result, there is a tremendous need for an apparatus to provide a pathway that is easy to manufacture and operate, cost-effective, and multifunctional. There is a great need for a portable apparatus that is easily and quickly movable between various locations, but can be securely positioned in order to provide a readily navigable and traversable pathway.
There is a need for a portable pathway that can be easily positioned in areas to prevent damage to barriers and other comparable structures, without affecting barrier integrity. There also remains a continuing unmet need for an apparatus that not only provides a path, but also provides adjustment devices that allow the apparatus to be used effectively on any contoured surface.
Embodiments disclosed herein provide for a portable pathway apparatus for providing a path over a surface that may include a pliable frame member; a row of mating holes disposed on each side of the pliable frame member; and a set of steps coupled to the pliable frame member. One or more of the set of steps may be coupled to the pliable frame member with a mount that aligns with the row of mating holes on each of the corresponding sides of the pliable frame member.
The apparatus may include at least one securing element coupled therewith. The surface may be an earthen surface. The securing element may be configured to secure the portable pathway to the earthen surface. The earthen surface may be proximate to a fluid containment source.
The earthen surface may include a contour, and wherein at least a portion of the pliable frame member is configured to conform to the contour.
The surface may include a contour. At least a portion of the pliable frame member may be configured to conform to the contour.
At least one of the set of steps may include an adjustment mechanism associated with a horizontal member. The adjustment mechanism may include a first linking member movingly connected with a second linking member. At least one of the first linking member and the second linking member may be connected to the horizontal member.
The apparatus may include a second set of steps. The set of steps may be coupled to the pliable frame member in a first orientation direction. The second set of steps may be coupled to the pliable frame member in a second orientation direction;
The apparatus may include a non-adjustable step disposed between the set of steps and the second set of steps.
Other embodiments of the disclosure pertain to a portable pathway apparatus for providing a path over a surface that may include a pliable frame member; a row of mating holes disposed on each side of the pliable frame member; and at least two adjustable steps connected to the pliable frame member. One or more of the at least two independently adjustable steps may be movable along a length of the pliable frame member. There may be a set of mounts configured to align with corresponding mating holes disposed in the pliable frame member.
The apparatus may include a securing element coupled with the pliable frame member. One or more of the at least two independently adjustable steps may include an adjustment mechanism. The mechanism may be configured with a first linking member movingly connected with a second linking member.
The surface may include an earthen surface proximate to a fluid containment source. The fluid containment source may be a tank.
There may be a first step of the at least two adjustable steps that may be coupled to the pliable frame member in a first orientation direction. There may be a second step of the at least two adjustable steps that may be coupled to the pliable frame member in a second orientation direction. There may be a non-adjustable step disposed between the first step and the second step.
Yet other embodiments of the disclosure pertain to a portable pathway apparatus for providing a path over a surface that may include a pliable frame member comprising rubber; a row of mating holes disposed on each side of the pliable frame member; and a plurality of steps coupled to the pliable frame member. An at least one of the plurality of steps may be coupled to the pliable frame member with a mount that is connectable with the row of mating holes on each of the corresponding sides of the pliable frame member.
The apparatus may include at least one securing element coupled therewith. The securing element may be configured to secure the portable pathway to the surface. The surface may be proximate to a fluid containment source.
The surface may include an earthen surface having a contour. At least a portion of the pliable frame member may be configured to conform to the contour.
One or more of the plurality of steps may include an adjustment mechanism associated with a horizontal member. The adjustment mechanism may include a first linking member movingly connected with a second linking member.
The surface may be an earthen surface proximate to a fluid containment source.
The apparatus may include a first step of the plurality of steps coupled to the pliable frame member in a first orientation direction. There may be a second step of the plurality of steps coupled to the pliable frame member in a second orientation direction. There may be a non-adjustable step disposed between the first step and the second step.
Other aspects and advantages of the disclosure will be apparent from the following description and the appended claims.
Specific embodiments of the present disclosure will now be described in detail with reference to the accompanying Figures. Like elements in the various figures may be denoted by like reference numerals for consistency. Further, in the following detailed description of embodiments of the present disclosure, numerous specific details are set forth in order to provide a more thorough understanding of the disclosure. However, it will be apparent to one of ordinary skill in the art that the embodiments disclosed herein may be practiced without these specific details. In other instances, well-known features have not been described in detail to avoid unnecessarily complicating the description.
In addition, directional terms, such as “above,” “below,” “upper,” “lower,” “front,” “back,” etc., are used for convenience in referring to the accompanying drawings. In general, “above,” “upper,” “upward,” etc. refer to a direction toward the Earth's surface, but is meant for illustrative purposes only, and the terms are not meant to limit the disclosure.
Referring now to
The portable apparatus 200 may be constructed of a number of interconnected components and subcomponents. Any of the components or subcomponents may be constructed of materials, such as, steel, aluminum, rubbers, composite plastics, wood, or combinations thereof. The portable apparatus 200 may include a component that includes a pliable frame member 202, which may have an associated length, L, and width (not shown). In some embodiments, the length of the frame member 202 may be in the range of about 4 to 8 feet, and the width may be in the range of about 1 to 4 feet. In other embodiments, the length and the width may be determined by whatever requirements need to be met in order to provide a traversable pathway; however, the length and width of the frame member 202 are not meant to be limited, and as such, may be any length and/or width whatsoever.
The pliable frame member 202 may be made of a durable material configured to withstand extreme environments, such as weather conditions, continuous usage, heavy wear-and-tear, etc. Although the apparatus 200 may just as well include a frame member of a rigid construction, such as one or more connected steel pieces, the portable pathway apparatus 200 may generally be considered to have a one piece pliable frame member 202 configured such that the apparatus 200 may readily conform to contours of the surface 210 where the apparatus 200 may be placed thereon.
Accordingly, the pliable frame member 202 may include, for example, one or more solid, one-piece layers of rubber (414,
The portable apparatus 200 may include “green” technology because the apparatus may be manufactured and/or put together from recycled materials. For example, the pliable frame member 202 may be made from old rubber tires or other previously used rubber materials. As such, the portable apparatus 200 may provide a synergistic effect of preventing damage to surfaces 210, while also reducing waste materials.
As mentioned, the pliable frame member 202 may thus include physical properties associated with at least some durability and toughness, but also flexibility and conformability. The frame member 202 may include at least one step 204 sturdily and/or adjustably connected thereto, as well as at least one securing element 206 that may be coupled with the pliable frame member 202.
The at least one securing element 206 may be configured to secure the portable pathway 200 to the surface 210. For example, the securing element 206 may be a solid-metal, spikeable structure connected to the bottom of the frame member 202 that may be easily insertable into soft surfaces, such as the ground. However, the type of securing element 206 is not meant to be limited, and could be other devices, such as rubber spikes, grommets, double-sided tape or other adhesives. Thus, this type of securing element 206 may be particularly useful when a spikeable structure is not suitable, such as when the surface 210 is hardened, like concrete, or when it is preferred that the surface 210 is not damaged by insertable features, such as a rooftop.
In addition to a single step 204, there may be one or more additional steps 208 connected to the pliable frame member 202, such that the pathway apparatus has a plurality of steps 204 and 208. In some embodiments, any of the steps 204 and/or 208 may be independently adjustable, while in other embodiments each one of the steps 204 and 208 may be independently adjustable. There may be a plurality of steps 204, 208 spaced equidistantly from one another, as indicated by spacing arrows 290, however, it is not necessary that this is the case for each and every step. As such, some steps 204, 208 may be spaced equidistantly from others, while other steps 208 are spaced apart by varying distances.
Referring briefly to
As shown in
The step 404 may include a layer 442 disposed on the horizontal member 444, with the layer 442 configured to, for example, prevent corrosion, prevent accidental slippage, provide improved traction, friction, etc. The layer 442 may be a topical surface that is textured or coated with a pattern, coating, or other comparable substance to provide a non-slip surface.
The step 404 may include a number of other subcomponents, including subcomponents that may provide the step 404 with the ability to adjustably move with respect to the pliable frame 402. For example, the step 404 may include the aforementioned horizontal member 444 connected with various linking members 445. The one or more linking members 445 may be securely, but movingly attached to the horizontal member 444. In addition, a first linking member 445 may be securely, but movingly attached to a second linking member 445A. Although linking members 445 and 445A are illustrated with structural differences, the linking members may just as well be substantially similar. In some embodiments, there may be a first linking member 445 and second linking member 445A connected on a first side (as shown) of the horizontal member 444, and there may be other linking members 445, 445A connected on a second side (not shown) of the horizontal member 444.
Linking members 445 and 445A may include a number of configurations and variations. For example, linking member 445 may include one or more apertures 433, while linking member 445A has no apertures 433. The apertures 433 may be used as passages through which pins 436 may be disposed therein. The pins 436 may be, for example, bolts (with nuts), screws, nails, or other fastener devices that may be used to fix the relationship of the linking members 445 and 445A, such that the level of the step 404 may be adjusted to and secured in its desired position. In one embodiment, the desired position of the step 404 may include one or more steps adjusted until the horizontal member 444 is substantially planar to a horizontal plane (250,
The linking members 445 and 445A may connect together as part of an adjustment mechanism 470. As such, the adjustment mechanism 470 may include the first linking member 445 movingly coupled with the second linking member 445A. As mentioned, the pin 436 may be inserted into one of the apertures 433 of the linking member 445, and also through an aperture (not shown) of linking member 445A. Any of the linking members 445 and 445A may have ends 447 and 447A, respectively, connected with horizontal member 444. The ends 447 and/or 447A may be connected to the horizontal member 444 with a pin 432 inserted through corresponding apertures (not shown). There may be an opening 441 disposed in the frame member 402 that may be used to accommodate upward and/or downward movement of any of the linking members 445.
Although the adjustment mechanism 470 is depicted in
Accordingly, although not shown here, the first linking member 445 may have a slot, whereby pin 436 may be loosened so that the linking member 445 and linking member 445A may be slidably adjusted and/or moved with respect to each other. Once the desired adjustment is made, the pin 436 may be secured, such that the linking member 445 and 445A are secured with each other and no longer slidably movable. In order to obtain the desired level of surface 444, a carpenters level may be used as a guide or indicator to adjust the step 404 to its desired position. In an exemplary embodiment, an indicator 475 may be disposed on one or more of the steps 404 that may be used to indicate level.
Referring again to
The surface 210 upon which the pathway apparatus 200 may be applied against may be any kind of surface that may at some point require walking upon or traversing. As illustrated, the surface 210 may be a generally flat earthen surface 224, such as the ground. The earthen surface 224 may also be contoured, such as, for example, a mound, a rolling hill, the side of a hill, etc. As shown in
In some embodiments, the earthen surface 224 may be a permanent or temporary barrier created, for example, to encompass a tank farm. In other embodiments, the earthen surface 224 may be a berm or a dune used, for example, to protect inland shoreline areas from tidal flows or flood waters.
As such, it would be apparent to one of skill in the art that the apparatus 200 may be used on the surface 210 that may be thought of as a naturally existing barrier, as well as a man-made barrier. Moreover, it would be apparent to one of skill in the art that the apparatus is not limited to the surface 210 that may be earthen in nature, such as the dune or a hillside, but the apparatus 200 could just as well be used on made-made surfaces, such as steel barriers, concrete barriers, rooftops, etc.
Referring now to
The portable apparatus 300 may be constructed of a number of interconnected components and subcomponents, such as frame member 302. The frame member 302 may be made of a durable material configured to withstand extreme environments, such as harsh weather conditions, continuous usage, heavy wear-and-tear, etc. Although the apparatus 300 may just as well include a frame member of a rigid construction, such as one or more connected steel pieces, the portable pathway apparatus 300 may generally be considered to have a one piece pliable frame member 302 configured so that the apparatus 300 may readily conform to contours of the surface 310 where the apparatus 200 may be placed thereon.
As such, the frame member 302 may thus include physical properties associated with at least some durability and toughness, but also flexibility and conformability. The frame member 302 may include at least one step 304 sturdily and/or adjustably connected thereto, as well as at least one securing element (not shown) that may be coupled with the frame member 302, whereby the apparatus 300 may be securely connected to the surface 310.
The frame member 302 may provide the apparatus 300 with the ability to distribute forces. For example, when an operator (not shown) steps onto the bare surface 310, the pressure is applied to the surface 310 directly at the operators step. In comparison, when the operator steps onto the apparatus 300, the pressure of the step may be distributed across the frame member 302, such that pressure applied to the surface 310 at the point of the step is minimal or marginalized, and instead the forces are distributed across the area of the frame member surrounding the operator's step.
In addition to a single step 304, there may be one or more additional steps 308 connected to the frame member 302, such that the pathway apparatus 300 has a plurality of steps 304 and 308. In some embodiments, any of the steps 304 and/or 308 may be independently adjustable, while in other embodiments each one of the steps 304 and 308 may be independently adjustable. There may be a plurality of steps 304, 308 spaced equidistantly, as indicated by spacing arrows 390, however, it is not necessary that this is the case for each and every step. As such, some steps 304, 308 may be spaced equidistantly from others, while other steps 308 are spaced apart by varying distances.
As shown in
The surface 310 upon which the pathway apparatus 300 may be applied against may be any kind of surface that may at some point require walking upon or traversing. While the surface 310 may be a generally flat earthen surface, such as the ground, the earthen surface may include a mound, hill, or other comparable contour. As shown in
While physical dimensions of the apparatus 300 are not significant to the disclosure, certain embodiments may be described with dimensions in order to provide a reader with a general reference. A horizontal member (444,
Referring now to
Accordingly, apparatus 500 may be part of a tank farm system 501 located in part of a petrochemical facility 503, whereby system 501 may include an ingress and/or egress pathway to a tank farm 555. Because of the potential that tanks 505 may leak, the barrier 524 may be emplaced or built around tanks 505 in order to form a perimeter therearound. In order to add or remove fluids from one or more of the tanks 505, such as via piping 580, a valve 513 may require actuation.
An operator 511 may traverse the barrier 524 from point A to point B by walking over the portable pathway 500. In order to provide the best pathway, the apparatus 500 may be optimized by adjusting one or more steps 504 that may be movingly disposed on a frame member 502. The frame member 502 may be made of a durable material configured to withstand extreme environments, such as weather conditions, continuous usage, heavy wear-and-tear, etc. As illustrated, the frame member 502 may be pliable, such that the frame member 502 may readily conform to any contours or other non-uniform/uneven surfaces of the barrier 524.
The frame member 502 may include the one or more steps 504 sturdily and/or adjustably connected thereto, as well as at least one securing element (406,
As illustrated in
The operator 511 may obtain substantially planar steps 504 by adjusting one or more of corresponding adjustment mechanisms 570. As such, the step(s) 504 may include a number of other subcomponents, including subcomponents that may provide the step 504 with the ability to adjustably connect to the frame 502. For example, the step 504 may include various linking members 545. As shown, there may be an upper linking member 545A movingly (e.g., slidingly, telescopingly, etc.) engaged with a lower linking member 545B. As such, the upper linking member 545A may be securely attached to a horizontal member 544, while the lower linking member 545B may be securely attached to mount 585. The linking members may be attached to other components by common attachments, such as bolted, riveted, welded, integrally formed, etc.
Although any of the linking members 545 may have structural differences, the linking members 545 may just as well be substantially similar, other than the location where the linking member 545 is located on the apparatus 500. Linking members 545 may include a number of variations, which may include apertures and/or slots. As shown, the lower linking member 545B may include a slot 571, while upper linking member 545B may include a protrusion 572 that corresponds with the slot 571 for adjustably moving therein. The protrusion may be, for example, a bolt or the like that may be loosened, such that the bolt may move up and down in the slot 571 until the member 544 is in the desired position. Once the member 544 is in the desired position, the bolt may be tightened, such as with a corresponding nut, or with any other tightening device as would be known to one of ordinary skill in the art.
Although described as a bolt, the protrusion 572 may be screws, nails, or other fastener devices that may be used to fix the relationship of the linking members 545A and 545B so that the level of the member 544 may be adjusted to its desired position.
The horizontal member 544 may also pivotably connect with mount 585, such as via a pin or other hinge device 532. The pin 532 may be, for example, inserted into corresponding apertures (not shown) of the member 544 and mount 585, respectively. In addition, mount 585 may have a mating connection 581, such that the mount 585 may be used to provide coupling between the step 504 and the frame 502. Although connection 581 is shown as external, the mount 585 may be disposed within the frame 502. In some embodiments, the mount 585 may be integral with the frame 502.
The connection 581 may be the result of mating holes 583 disposed within the frame member 502. As shown, there may be one or more rows of mating holes disposed on along one or both sides of the frame member 502. Any of the steps 504 and/or 508 may couple to the frame member 504 via connectors disposed through mount 585 and holes 583, which may be, for example, carriage bolts or the like, thereby forming connection 581. As mentioned, the placement holes 583 may be used for adequately spacing steps 504 and/or 508 apart from each other, as desired or needed.
In some embodiments, the barrier 524 may have a crested portion 587. As such, the apparatus 500 may include a non-adjustable step, shown in
As shown, a handrail 584 may also be used in conjunction with the pathway apparatus 500. In some embodiments, the handrail 584 may be coupled with the apparatus 500, while in other embodiments the handrail 584 may be securely mounted to the barrier 524 in a location adjacent to where the pathway 500 is placed.
The handrail 584 may be, for example, pivotally coupled to the apparatus 500 by coupler 582, which may be a hinge-type mechanism. With a pivotal coupling, the handrail 584 may be positioned upright and securely locked in place with respect to the frame 502, as would be known to one of ordinary skill in the art. Regardless of whatever handrail 584 configuration may be desired, the handrail 584 may retain proper relationship to the portable pathway 500.
In conjunction with the figures, embodiments disclosed herein may include a method of providing a traversable path along a surface. The method may include various steps, such as a user placing a portable pathway apparatus 200 onto the surface 210. The portable pathway apparatus may include at least one adjustable step connected thereto, which may make it easier to traverse (e.g., walk, climb, navigate, etc.) over the provided path. For example, the apparatus 200 may be placed on a steep terrain or other contour, such as a rooftop, whereby the presence of one or more steps may make it easier to climb or walk thereon.
The portable apparatus may also include, for example, a pliable frame member 202 coupled with the at least one adjustable step 204, and a securing element 206 coupled with the pliable frame member 202. When necessary or desired, the method may include the step of adjusting one or more of the steps to a desired position.
The method may include the step of securing the portable pathway 200 wherever the pathway is needed, such as by inserting securing elements 206 into the surface 210. As such, the portable pathway apparatus may be secured in situ.
The method may include securing the pathway to a surface that may be an earthen surface having at least one angled contour. In one embodiment, the portable pathway may be placed substantially symmetrically over one or more angled contours or surfaces. In another embodiment, the surface may include a manmade surface.
The method may include the portable pathway having a plurality of additional adjustable steps connected thereto, wherein each of the steps is independently adjustable. As such, the method may include the step of adjusting at least one of the steps until a base of the at least one adjusted step is substantially planar to a horizontal surface. In other embodiments, the method may include the step of adjusting every one of the steps until every adjusted step has a base that is substantially planar to a horizontal surface.
From the above description, it can be seen that a portable, adjustable pathway is provided for use in temporary or permanent applications. The portable apparatus is beneficially durable for long-term use, but readily movable if necessary. The portable apparatus is particularly advantageous for situations where surfaces have angles associated therewith that make the surface difficult to traverse. Beneficially, the portable apparatus may be used in residential, industrial, and recreational areas.
The portable apparatus may beneficially be sized to any length or width as necessary to provide a traversable path. The lightweight design means the portable apparatus may be easily moved or transported. Any number of adjustable steps may be added. Particularly beneficial is the fact that the portable apparatus may be used on any surface, such as man-made surfaces or natural terrains
The portable apparatus may be placed in areas to prevent damage to barriers and other comparable structures, without affecting barrier integrity. Beneficially, steps of the apparatus may be adjusted to allow the apparatus to be used effectively on any contoured surface. The portable apparatus may advantageously take advantage of “green” technology because the apparatus may be manufactured from various recycled or waste materials. In addition, the apparatus may include non-flammable materials, such that the apparatus will prevent the transfer or transmission of fire outside of a barrier. As mentioned, the frame member may thus include physical properties associated with at least some durability and toughness, but also flexibility and conformability. The frame member may advantageously be capable of withstanding forces under all kinds of circumstances and environmental conditions, often for a prolonged period of time without need for replacement or repair.
While the present disclosure has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments may be devised which do not depart from the scope of the disclosure as described herein. Accordingly, the scope of the disclosure should be limited only by the attached claims.
This application is a continuation of U.S. patent application Ser. No. 13/968,194, filed on Aug. 15, 2013, which is a continuation of U.S. patent application Ser. No. 12/924,591, filed on Sep. 30, 2010. The disclosure of each application is incorporated by reference herein in entirety for all purposes.
Number | Name | Date | Kind |
---|---|---|---|
505343 | Austin | Sep 1893 | A |
1363418 | Jacobs | Dec 1920 | A |
2708543 | Matich | May 1955 | A |
3464516 | Sylvester | Sep 1969 | A |
4041722 | Terlesky | Aug 1977 | A |
4959935 | Stob | Oct 1990 | A |
5244058 | Carlson | Sep 1993 | A |
5626440 | Greene, Jr. | May 1997 | A |
6467234 | Marshall | Oct 2002 | B1 |
7946084 | Gibson | May 2011 | B2 |
20020046543 | Neuleib | Apr 2002 | A1 |
20070199258 | Reeves | Aug 2007 | A1 |
20130000231 | Greaves | Jan 2013 | A1 |
Number | Date | Country |
---|---|---|
2131475 | Jun 1984 | GB |
Entry |
---|
Abtech Safety, Tuff Step, 2 pages, 2008. |
Number | Date | Country | |
---|---|---|---|
20150167309 A1 | Jun 2015 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 13968194 | Aug 2013 | US |
Child | 14628272 | US | |
Parent | 12924591 | Sep 2010 | US |
Child | 13968194 | US |