Ladders have the problem that when in use, they are generally unstable. This lack of stability will often lead to injury or even death. Indeed, injuries related to ladder use are a leading problem in construction, repair and other industries. Until now, the most common way to remedy an unstable ladder is to require a second person to be positioned at the base of the ladder, or to construct a form of scaffolding, which is both costly and time-consuming.
Accordingly, there is a need for a collapsible multi-surface, self-supporting ladder with an increased stability that does not require a second person or unnecessary assembly time. One aspect of the present disclosure is to provide a configuration that will help prevent injuries for an individuals who is climb, work on, dismount from, or do any other work with a ladder. It is contemplated that the exemplary embodiments disclosed below can be used on, inter alia, an extension ladder, pull-down attic ladder, one-piece straight ladder or any other ladder where additional stability is needed.
According to one exemplary embodiment, the collapsible ladder assembly system includes a larger ladder section and a smaller strut section, wherein the smaller strut ends are pivotally connected to the larger ladder section at a point that is at or below the midpoint of the larger ladder section, therefore allowing the system to be collapsible. The larger ladder section and smaller strut section are further connected by a rigid adjustable linkage, or spreader, at points that are below the pivotable connection that are capable of adding further stability and maintaining a consistent predetermined angle or distance between the feet of the larger ladder and the smaller strut section.
According to another exemplary embodiment, the collapsible ladder assembly system includes a pre-existing larger ladder section and a smaller strut section, wherein the smaller strut ends are detachably and pivotally connected to the pre-existing larger ladder section at a point that is at or below the midpoint of the larger ladder section, therefore allowing the system to be collapsible and/or detachable. The larger ladder and smaller strut sections are connected by a rigid adjustable linkage, or spreader, at points that are below the pivotable connection. These linkage connections can be detachable at the pre-existing large ladder end and permanent at the smaller strut section, or a variation thereof.
The exemplary ladder configurations disclosed herein provide a means for stability on multiple surfaces. At the ground contacting point, the point where the rail or strut ends meet the ground, there are adjustable gripping feet or shoes, which can be independently or in combination vertically or angularly adjusted for maximum stability.
These and other advantages of the present invention will be readily understood with reference to the following specification and attached drawing wherein:
Referring to
Referring now to
Referring to
Referring to
Referring to
The underside of the shoe 46 includes a gripping means 62 to minimize slippage at the ground contact point. Depending on the application, said gripping means 62 could be a rubber pad for use on a relatively smooth hard surface, spiked (as seen in
Alternative foot embodiments are shown in
Referring now to
Referring to
The ladder system 20 structure as described can be constructed from any material known in the art of ladder fabrication, including but not limited to wood, metal, metal alloys, fiberglass, composites, carbon fiber, plastic or a combination thereof. Similarly, the rails of the smaller strut section, or ladder system 20 need not be the same material as the larger ladder section.
Obviously, many modifications and variations of the present invention are possible in light of the above teachings. Thus, it is to be understood that the invention may be practiced otherwise than as specifically described above.
Number | Name | Date | Kind |
---|---|---|---|
202426 | Evans | Apr 1878 | A |
281977 | Coons | Jul 1886 | A |
475935 | Crews | May 1892 | A |
515783 | Moore | Mar 1894 | A |
886737 | Taylor | May 1908 | A |
1385319 | Enke | Jul 1921 | A |
1811722 | Kimberlin | Jun 1931 | A |
1812119 | Ruse | Jun 1931 | A |
2007057 | McNeal | Jul 1935 | A |
2471110 | Jenkins | May 1949 | A |
2584197 | Garner | Feb 1952 | A |
2887260 | McKinnie | May 1959 | A |
2934163 | Ladewski | Apr 1960 | A |
3288248 | Gurian et al. | Nov 1966 | A |
3508628 | Conrad | Apr 1970 | A |
3933221 | Sorenson | Jan 1976 | A |
4069893 | Blackstone | Jan 1978 | A |
4147231 | Chantler et al. | Apr 1979 | A |
4207886 | Sorenson | Jun 1980 | A |
4244446 | Mair | Jan 1981 | A |
4421206 | Kummerlin | Dec 1983 | A |
4483415 | Disston et al. | Nov 1984 | A |
4520896 | Disston et al. | Jun 1985 | A |
4565262 | Hawkins | Jan 1986 | A |
4669576 | Jones | Jun 1987 | A |
4723629 | Vanden Hoek et al. | Feb 1988 | A |
4798262 | Margolies | Jan 1989 | A |
4899849 | Levi et al. | Feb 1990 | A |
4949809 | Levi et al. | Aug 1990 | A |
5033584 | Battle | Jul 1991 | A |
5086876 | Severson | Feb 1992 | A |
5165501 | Donahey | Nov 1992 | A |
5267631 | Mendel | Dec 1993 | A |
5341899 | Casamento | Aug 1994 | A |
5522473 | Moselsky | Jun 1996 | A |
5551529 | Molitor | Sep 1996 | A |
5590739 | High et al. | Jan 1997 | A |
6382353 | Laug | May 2002 | B2 |
6450290 | Spak | Sep 2002 | B1 |
6533071 | Smith | Mar 2003 | B1 |
6948591 | Scott et al. | Sep 2005 | B2 |
7163084 | Blehm | Jan 2007 | B1 |
7293630 | Trebec | Nov 2007 | B1 |
D565745 | Meyers et al. | Apr 2008 | S |
7487859 | Wang | Feb 2009 | B2 |
20010015303 | Laug | Aug 2001 | A1 |
20060272899 | Chang | Dec 2006 | A1 |
20070181370 | Kemp-Banks | Aug 2007 | A1 |
20070261918 | Trebec | Nov 2007 | A1 |
20080000720 | Porch et al. | Jan 2008 | A1 |
20090045013 | McMurray | Feb 2009 | A1 |
20090107765 | Germond | Apr 2009 | A1 |
20100147623 | Pocos | Jun 2010 | A1 |
20100236866 | Huang | Sep 2010 | A1 |
20100300805 | Moss et al. | Dec 2010 | A1 |
20110067954 | Deal | Mar 2011 | A1 |
Number | Date | Country |
---|---|---|
2099060 | Dec 1982 | GB |
2146688 | Apr 1985 | GB |
2166793 | May 1986 | GB |
2218451 | Nov 1989 | GB |
Entry |
---|
PCT/US10/29606—International Bureau preliminary report on patentability dated Oct. 13, 2011. |
PCT/US10/29606—ISR dated May 21, 2010. |
International Search Report and Opinion for International Application No. PCT/US2011/050882, with a mailing date of Jan. 5, 2012. |
Number | Date | Country | |
---|---|---|---|
20100252364 A1 | Oct 2010 | US |