Patent Application
20140190768
The present invention relates generally to ladders and, more particularly, to configurations of stepladders and methods of making and using stepladders.
Ladders are conventionally utilized to provide a user thereof with improved access to elevated locations that might otherwise be inaccessible. Ladders come in many shapes and sizes, such as straight ladders, straight extension ladders, stepladders, and combination step and extension ladders. So-called combination ladders may incorporate, in a single ladder, many of the benefits of multiple ladder designs.
Ladders such as stepladders are highly utilized by various tradesman as well as homeowners. Such ladders are “self-supporting” in that they do not require the upper end of the ladder to be positioned against a supporting structure, such as a wall or the edge of a roof. Rather, stepladders include multiple feet (typically either three or four) that are spaced from one another and provide a stable base or foundational structure to support the ladder and a user when placed on, for example, a floor or the ground. This enables a user of the ladder to gain access to elevated areas even though the accessed area may be, for example, in the middle of a room, away from walls or other potential supporting structures that are conventionally required when using a straight ladder or an extension ladder.
For these reasons and others, step ladders are one of the more popular forms of ladders and comprise a large segment of the ladder market. However, there are always areas of potential improvement. For example, conventional configurations of stepladders are often considered bulky. The bulky size of the ladder, when they are in a collapsed or storable state, can make it difficult to carry the ladder and may cause it to take up more space than desired when being stored or transported. Moreover, the volume occupied by a ladder has significant impact on shipping costs and on the amount of ladders that may be stored, displayed, or both, within a retail establishment or a distributor's warehouse.
In other words, when in a collapsed state, the volume occupied by a stepladder is largely air because the stepladder is constructed generally as a frame-like structure. The structure conventionally includes a first assembly including a set of spaced-apart side rails coupled to a plurality of steps or rungs. Another assembly includes set of spaced-apart side rails and is conventionally positioned adjacent the first assembly, when in a collapsed or storable state, to define a volume generally having a height equal to that of the taller of the first assembly and the second assembly, a width equally to that of the wider of the first assembly and the second assembly, and a depth that is equal to a sum of the depth of the first assembly and the depth of the second assembly.
Thus, it would be advantageous to provide stepladders that define a smaller volume when in a collapsed or stored state while maintaining similar strength and stability characteristics of a ladder having a similar size and capacity when in a deployed or useable state. It would also be advantageous to provide methods related to manufacturing and using stepladders that result in reduced bulk and volume of such ladders while in a collapsed state and also maintaining the general usability of the ladder.
The present invention relates to ladders and, more particularly, various configurations of stepladders, as well as to methods relating to the use and manufacture of stepladders.
In accordance with one embodiment, a stepladder is provided that comprises a top cap, a first assembly and a second assembly. The first assembly has a pair of spaced apart rails pivotally coupled with the top cap. The second assembly includes at least one rail pivotally coupled with the top cap. The first assembly and second assembly are configured to be displaced relative one another such that the stepladder is selectively positionable between a first, deployed state and a second, collapsed state. The first assembly, the second assembly and the top cap are cooperatively configured such that the at least one rail of the second assembly is at least partially nested within an envelope defined by the pair of spaced apart rails of the first assembly when the step ladder is in a collapsed state.
In one embodiment, the first assembly of the stepladder may further include a plurality of rungs coupled between the pair of spaced apart rails. Additionally, the at least one rail of the second assembly comprises a pair of spaced apart rails. In one embodiment, the stepladder may further comprise: a pair of spaced apart spreaders with each spreader being coupled between the first assembly and the second assembly and having a hinge; and a pair of struts with each strut being coupled between an associated spreader and a rail of the pair of spaced apart rails of the second assembly. In one particular embodiment, each strut of the pair of struts maintains a substantially parallel relationship to an associated rail of the pair of spaced apart rails of the first assembly.
In accordance with another embodiment of the present invention, a stepladder is provided that includes a first assembly having a pair of spaced apart rails, the rails exhibiting a first depth between an exterior edge and an interior edge thereof. The stepladder further includes a second assembly having a pair of spaced apart rails, the rails exhibiting a second depth between an interior edge and an exterior edge thereof. The second assembly is pivotally positionable relative to the first assembly between a first, deployed state and a second, collapsed state. A total depth of the stepladder, when in the collapsed state, is less than the sum of the first depth and the second depth.
In accordance with another embodiment of the present invention, a stepladder includes a first assembly including a pair of spaced apart rails defining a first volume. The stepladder further includes a second assembly including a pair of spaced apart rails defining a second volume. The second assembly is pivotally positionable relative to the first assembly between a first, deployed state and a second, collapsed state. A total volume of the stepladder, when in the collapsed state, is less than a sum of the first volume and the second volume.
In accordance with yet another embodiment of the present invention, a stepladder includes a first assembly including a pair of spaced apart rails defining a first volume and a second assembly including a pair of spaced apart rails defining a second volume. The second assembly is pivotally positionable relative to the first assembly between a first, deployed state and a second, collapsed state, wherein the first volume and the second volume at least partially merge when the stepladder is in the collapsed state.
In accordance with another embodiment of the present invention, a method is provided for storing a ladder having a first assembly including a pair of spaced apart rails defining a first volume and a second assembly including a pair of spaced apart rails defining a second volume. The method includes collapsing the ladder from a first deployed state to a second, collapsed state such that the ladder, when in the second collapsed state, defines a total volume that is less than the sum of the first volume and the second volume.
The foregoing and other advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings in which:
Referring generally to
The stepladder 100 also includes a second assembly 108 having a pair of spaced apart rails 110. The second assembly 108 need not include a plurality of rungs between the spaced apart rails 110. Rather, bracing or other structural components may be used to provide a desired level of support and strength to the spaced apart rails 110. However, in some embodiments, the second assembly 108 may include rungs configured generally similar to those associated with the first assembly 102. The second assembly 108, thus, may be used to help support the stepladder 100 when in an intended operational state, such as depicted generally in
The first and second assemblies 102 and 108 may be formed of a variety of materials and using a variety of manufacturing techniques. For example, in one embodiment, the rails 104 and 110 may be formed of a composite material, such as fiberglass, while the rungs and other structural components may be formed of aluminum or an aluminum alloy. In other embodiments, the assemblies 102 and 108 (and their various components) may be formed of other materials including other composites, plastics, polymers, metals and metal alloys.
A top cap 112 is coupled to a portion of the first assembly 102 and a portion of the second assembly. For example, the top cap 112 may be pivotally coupled to an upper end 114 of each rail 104 of the first assembly 102 along a common axis, and it may also be pivotally coupled to an upper end 116 of each rail 110 of the second assembly 108 along another common axis. It is noted that used of the term “upper end” merely refers to a relative position of the described components when the stepladder 100 is in an intended use orientation. In one embodiment, the top cap 112 may simply be a component configured to facilitate relative coupling of the first and second assemblies 102 and 108. In other embodiments, the top cap may include features that enable it to be used as a tray or a tool holder. Thus, the top cap 112 may be used to organize a user's tools and resources while working on the stepladder 100. For example, such a top cap is described in U.S. patent application Ser. No. 12/399,815 entitled LADDERS, LADDER COMPONENTS AND RELATED METHODS and filed Mar. 6, 2009, the disclosure of which is incorporated by reference herein in its entirety. It is noted that, for safety purposes, the top cap is not conventionally configured as a “rung” or a “step.”
As with other components of the stepladder 100, the top cap 112 may be formed from a variety of materials. In one embodiment, the top cap 112 may be formed from a plastic material that is molded into a desired size and shape.
A locking mechanism 118 may be used to prevent the top cap 112 from pivoting relative to either the first assembly 102 or the second assembly 108. For example, the locking mechanism 118 may include a pair of retractable pin members with each pin extending through a hole in an associated rail (e.g., rail 110) and an associated hole in the top cap 112 to prevent rotation of the top cap 112 relative to the rail (e.g., rail 110). In such an example, the pins may be biased to remain engaged with the rails and top cap 112. An actuating mechanism (e.g. a pull cord 119 or other structure or mechanism) may then be used to selectively retract the pins and cause them to disengage the top cap 112, the rails (e.g., rails 110) or both.
A pair of hinged braces, referred to herein as spreaders 120, are used to maintain a desired angle between the first and second assemblies 102 and 108 when the stepladder 100 is in a deployed or useable state. The hinged nature of such spreaders 120 helps to enable the first and second assemblies 102 and 108 to collapse into a stored state and then help lock the assemblies 102 and 108 in position relative to one another when in a deployed or useable state.
Referring more specifically to
Additionally, when in a collapsed state, the second assembly 108 becomes nested within the first assembly 106. In other words, the interior surface or edge 122 of the rails 104 of the first assembly 102 do not simply abut, or become placed immediately adjacent, the interior surface or edge 124 of the rails 110 of the second assembly 108. Rather, the interior edge 124 of the rails 110 of the second assembly 108 are actually displaced beyond the interior edge 122 of the rails of the first assembly 102 and towards the exterior surface or edge 126 (also referred to as the face edge) of the rails 104 of the first assembly 102.
Stated yet another way, an envelope or volume of space is defined by the rails 104 of the first assembly 102 and the rotated top cap 112. When the stepladder 100 is in a collapsed state, the second assembly 108 becomes at least partially disposed within the volume or envelope defined by the first assembly 102 or the volume or envelope defined by the first assembly 102 and the rotated top cap 112. In one embodiment, such as more specifically shown in
Such a configuration is in contrast to conventional stepladders wherein interior edges of rails in one assembly abut interior edges of rails of the other assembly. In the stepladder 100 of the presently described embodiment, the depth D of the stepladder 100, when in a collapsed state, is less than the sum of the depth d1 of the rails 104 of the first assembly 102 and the depth d2 of the rails 110 of the second assembly 108 (i.e., D<d1+d2). In some embodiments, the depth D of the stepladder 100 when in the collapsed state is substantially equal to the depth d1 of the rails 104 of the first assembly 102 (i.e., D≈d1). In contrast, the overall depth of conventional stepladders when in a collapsed state is equal to or greater than the sum of the individual depths of the rails (i.e., D≧d1+d2).
The reduction in depth D of the stepladder 100 when in a collapsed state provides significant advantages over conventional prior art ladders. For example, the reduction in depth D results in a corresponding reduction in volume of the stepladder 100 (the volume V being calculated as the depth D multiplied by the height H, and further multiplied by the width W—i.e., V=D×H×W—when the stepladder is in a collapsed state). A reduced volume V provides a significant reduction in the cost to ship or transport such ladders to distributors, retailers or end users. Additionally, the reduced volume of the collapsed stepladder 100 enables distributors and retailers to store a greater number of ladders in a given volume of storage or for a given amount of floor space Likewise, end users are able to store the stepladders in a smaller volume of space, whether that be in their garage, in a closet, on or in a vehicle, in a warehouse or the like. Stepladders with a reduced depth D are also easier to transport by and end user, whether they are being carried by hand, being transported by vehicle on a roof rack, within a car or truck or by some other mode.
Still referring to
The stepladder 100 may also include a plurality of braces 134 or other support structures coupled, for example, to the side rails 104 of the first assembly 102 and to the back or interior edges of the rungs 106. The braces 134 may be coupled to the rungs 106 adjacent the notches 130 such that the notches 130 are positioned between the rails 104 and the location of coupling between the braces 134 and the rungs 106. The use of braces 134 provides additional support and rigidity for the rungs 106 in light of the material removed from the rungs 106 to form the notches 130.
As previously noted, a locking mechanism 118 may be used to lock the top cap 112 relative to the first assembly 102, the second assembly 108 or both when the stepladder 100 is in a deployed condition similar to the fixed nature of a top cap (relative to at least one assembly) in a conventional prior art step ladder. However, the selective disengagement of the locking mechanism 118 from the top cap 112 enables the pivoting of the top cap 112 relative to each of the first assembly 102 and the second assembly 108 so that the first and second assemblies may be collapsed relative to one another in the manner described above.
Referring now to
The stepladder 200 also includes a second assembly 208 having a pair of spaced apart rails 210. The second assembly 208 need not include a plurality of rungs between the spaced apart rails 210. Rather, bracing or other structural components may be used to provide a desired level of support to the spaced apart rails 210. However, in some embodiments, the second assembly 208 may include rungs configured, for example, generally similar to those associated with the first assembly 202. The second assembly 208, thus, may be used to help support the stepladder 200 when in an intended operational state, such as depicted generally in
A top cap 212 is coupled to a portion of the first assembly 202 and a portion of the second assembly 208. For example, the top cap 212 may be pivotally coupled to an upper end 214 of each rail 204 of the first assembly 202, and it may also be pivotally coupled to an upper end 216 of each rail 210 of the second assembly 208. In one embodiment, the top cap 212 may simply be a component configured to facilitate relative coupling of the first and second assemblies 202 and 208. In other embodiments, the top cap may include features that enable it to be used as a tray or a tool holder as previously described.
The first and second assemblies 202 and 208 may be formed of a variety of materials and using a variety of manufacturing techniques such as has been described hereinabove with respect to the stepladder described in associated with
A pair of hinged braces, referred to herein as spreaders 220, are used to maintain a desired angle between the first and second assemblies 202 and 208 when the stepladder 200 is in a deployed or useable state. The hinged nature of such spreaders 220 provides support to the stepladder 200 when in a deployed state, but also helps to enable the first and second assemblies 202 and 208 to collapse into a stored state. A strut member 222 has one end pivotally coupled to the spreader 220 at a location between the hinge component 223 and the first assembly 202. A second end of the strut member 222 is pivotally coupled to the rails 210 of the second assembly 208 or the top cap 212 at a location generally adjacent to the pivotal coupling between the second assembly 208 and the top cap 212. In another embodiment, the second end of the strut member 222 may be coupled with the same pivot 225 that couples the second assembly 208 and the top cap 212.
Another strut member 224 may be coupled to the spreader 220 such that it extends from the portion of the spreader 220 between the hinge of the spreader and the second assembly 208 and towards the first assembly 202 when the stepladder 200 is in a deployed state as seen in
As previously noted,
It is also noted that the strut members 222, in conjunction with the spreader 220, effectively lock the top cap 212 in place when the ladder 200 is in a deployed state (i.e.,
As with the embodiment described with respect to
While the result is similar to that of the embodiment described with respect to
While the invention may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and have been described in detail herein. Of course, one or features of one described embodiment may be utilized in conjunction with one or more features of another described embodiment. It should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the following appended claims.
This application is a continuation of U.S. patent application Ser. No. 12/716,126, filed Mar. 2, 2010, pending, entitled STEPLADDERS AND RELATED METHODS, which claims the benefit of U.S. Provisional Patent Application No. 61/157,085 filed Mar. 3, 2009, entitled STEPLADDERS AND RELATED METHODS, and U.S. Provisional Patent Application No. 61/175,731 filed May 5, 2009, entitled LADDERS, LADDER COMPONENTS, LADDER ACCESSORIES, LADDERS SYSTEMS AND RELATED METHODS, the disclosures of which are incorporated by reference herein in their entireties.
| Number | Date | Country | |
|---|---|---|---|
| 61157085 | Mar 2009 | US | |
| 61175731 | May 2009 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 12716126 | Mar 2010 | US |
| Child | 14208745 | US |
