Abstract:
Safety ladders to provide egress from water to a dock or boat or the like are disclosed. Safety ladders in accordance with the present invention are mountable to a structure, upwardly collapsible to a first storage configuration, and downwardly extendible to a second climbing configuration.

Description:
PRIORITY CLAIM  
       [0001]     This application claims the benefit of U.S. Provisional Patent Application having Ser. No. 60/762,376 filed on Jan. 25, 2006, entitled “Safety Ladder”, the entire disclosure of which is incorporated herein by reference for all purposes. 
     
    
     TECHNICAL FIELD  
       [0002]     The present invention relates to safety ladders. More particularly, the present invention relates to safety ladders to provide egress from water to a dock or boat or the like.  
       SUMMARY  
       [0003]     In one aspect of the present invention a safety ladder is provided that is mountable to a structure, upwardly collapsible to a first storage configuration, and downwardly extendible to a second climbing configuration. The safety ladder comprises a first link comprising a rung portion positioned between a first upwardly extending member and a second upwardly extending member. The first and second upwardly extending members each comprise an end for mounting the ladder to the structure. The safety ladder also comprises a second link comprising a rung portion positioned between a first upwardly extending member and a second upwardly extending member. The first upwardly extending member of the second link comprises an end with an eye portion slidingly connected with the first upwardly extending member of the first link. The second upwardly extending member of the second link also comprises an end with an eye portion slidingly connected with the second upwardly extending member of the first link. The ladder may comprise any number of additional similar links.  
         [0004]     In another aspect of the present invention, a method of making a safety ladder that is mountable to a structure, upwardly collapsible to a first storage configuration, and downwardly extendible to a second climbing configuration is provided. The method comprises the steps of forming a first link by positioning a rung portion between first and second upwardly extending members, forming a second link by positioning a rung portion between first and second upwardly extending members, forming first and second eyes at first and second ends of the first and second upwardly extending members of the second link, respectively, and slidingly connecting the first and second eyes of the first and second ends of the first and second upwardly extending members of the second link with the first and second upwardly extending member of the first link, respectively.  
         [0005]     In yet another aspect of the present invention, a method of providing a safety ladder on a structure such as a dock is provided. The method comprises the steps of providing a ladder as described above, attaching the first link of the ladder to a structure, sliding the first and second links relative to each other to provide the ladder in a collapsed configuration wherein the rung portion of the first link is closer to the rung portion of the second link as compared to when the ladder is in an extended climbing configuration, and releasably holding the ladder in the collapsed configuration. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]     These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings where:  
         [0007]      FIGS. 1 and 2  are perspective views of an exemplary ladder in accordance with the present invention showing in particular a plurality of slidably interconnected links positioned in an extended or climbing configuration of the ladder;  
         [0008]      FIG. 3  is a side view of the ladder of  FIGS. 1 and 2 ;  
         [0009]      FIG. 4  is a top view of the ladder of  FIGS. 1 and 2 ;  
         [0010]      FIG. 5  is a front view of the ladder of  FIGS. 1 and 2 ;  
         [0011]      FIG. 6  is a front view of an exemplary ladder similar to the ladder of  FIGS. 1-5  in accordance with the present invention shown attached to a structure and configured in an extended or climbing configuration;  
         [0012]      FIG. 7  is a top view of the ladder of  FIG. 6 ;  
         [0013]      FIG. 8  is a partial top view of an eye at an end of an upwardly extending member of a first link as slidingly engaged with an upwardly extending member of a second link of a ladder in accordance with the present invention;  
         [0014]      FIG. 9  is a partial front view of the engaged eye of  FIG. 8 ;  
         [0015]      FIG. 10  is a partial bottom view of the engaged eye of  FIG. 8 ;  
         [0016]      FIG. 11  is a partial side view of the engaged eye of  FIG. 8 ;  
         [0017]      FIG. 12  is a partial perspective view of a mounting bracket in accordance with the present invention shown engaged with a hook portion of a mounting link of a ladder in accordance with the present invention; and  
         [0018]      FIG. 13  is a perspective view of an exemplary ladder in accordance with the present invention shown in a collapsed or storage configuration. 
     
    
     DETAILED DESCRIPTION  
       [0019]     In  FIGS. 1-13  an exemplary safety ladder  10  in accordance with the present invention is illustrated. In  FIG. 13 , safety ladder  10  is shown mounted to a structure  12  (a portion of a dock, for example) and upwardly collapsed in a first storage configuration. In  FIGS. 1-7  safety ladder  10  is shown downwardly extended to a second climbing configuration.  
         [0020]     Referring to  FIGS. 1-7 , safety ladder  10  comprises slidingly interconnected links  14 ,  16 ,  18 , and  20 , as illustrated. Link  14  preferably functions to mount ladder  10  to structure  12  and is described in more detail below. Links  16 ,  18 , and  20  function to provide climbing rungs for ladder  10  and are also interconnected in a way that allows links  16 ,  18 , and  20  to be positioned relative to link  14  in the collapsed storage configuration shown in  FIG. 13 . Any number of links may be used depending on the desired application for ladder  10 . The links are preferably designed with dimensions suitable for the particular application of the ladder.  
         [0021]     Referring to link  20  in particular, link  20  is generally u-shaped and comprises a rung portion  22  positioned between first upwardly extending member  24  and second upwardly extending member  26 . Eye  28  is provided at an end of first upwardly extending member  24  and slidingly engages first upwardly extending member  30  of link  18 . Similarly, eye  32  is provided at an end of second upwardly extending member  26  and slidingly engages second upwardly extending member  34  of link  18 . As shown, links  16  and  18  preferably have a structure similar to link  20  but may have a different structure.  
         [0022]     Referring to  FIGS. 8-11 , eye  32  of link  20  is shown in greater detail and is representative of an eye that can be used for any link of ladder  10  in accordance of the present invention. In  FIG. 9 a  front view of eye  32  as engaged with member  34  is shown and in  FIG. 11 a  right side view is shown.  FIGS. 8 and 10  show top and bottom views, respectively, with respect to the front view of  FIG. 9 . As illustrated, eye  32  is canted (angled or bent) relative to member  26 . Specifically, eye  32  is preferably canted back and to the right with respect to member  26  as viewed from the front of ladder  10 . As shown, eye  32  includes extending portion  36  that extends from member  26  and which can be used as a reference to define the preferred orientation of eye  32  with respect to member  26 . While extending portion  26  is illustrated as linearly extending, it is noted that extending portion  36  can be arcuate or otherwise curved or looped.  
         [0023]     As viewed from the side as shown in  FIG. 11 , extending portion  36  makes an angle a with member  26  and as viewed from the front as shown in  FIG. 9 , extending portion  36  makes an angle β with member  26 . Also, as shown in  FIG. 8 , extending portion  36  makes an angle γ with rung  20  as viewed from the top. Thus, eye  32  is canted back and to the right with respect to member  26  when viewing ladder  10  from the front. Preferably the angle α is between about 90 to 160 degrees. Preferably the angle β is between about 0 to 90 degrees. Preferably the angle γ is between about 90 to 160 degrees. More preferably the angle α is between about 110 to 130 degrees. More preferably the angle β is between about 10 to 30 degrees. More preferably the angle γ is between about 110 to 130 degrees. One preferred ladder in accordance with the present invention has angles for α, β, and γ of about 120, 20, and 120 degrees, respectively. Angles α, β, and γ are preferably chosen so that eye  32  can functionally slide with respect to member  34  to position link  20  in the collapsed and extended configuration of ladder  10  in accordance with the present invention.  
         [0024]     When ladder  10  is in the extended or climbing configuration, eye  32  (and eye  28 ) engages with rung  38  of link  18 . This engagement is preferably balanced so each of eyes  28  and  32  acts like a lever to balance or stabilize a link. That is, preferably, the cant or bend of eye  28  is symmetric to eye  32 . A similar engagement occurs with the other links of ladder  10 . This engagement between the eyes and rungs of ladder  10  helps to prevent the links of ladder  10  from moving relative to each other in a direction away from someone climbing ladder  10  and helps to stabilize ladder  10 . This engagement also helps provide rigidity and structural stability in a transverse or side to side direction.  
         [0025]     Link  14 , which can best be seen in  FIG. 1  is preferably designed to mount ladder  10  to structure  12  as shown in  FIGS. 6-13 . As shown, link  14  includes a rung portion  40  positioned between first upwardly extending member  42  and second upwardly extending member  44 . Hook portion  46  is provided at an end of first upwardly extending member  42  and hook portion  48  is provided at an end of second upwardly extending member  44 . Link  14  also preferably includes a stabilization bar  50  that extends from rung portion  40 .  
         [0026]     Referring to  FIG. 12  in particular, hook portion  46  of member  42  is shown as engaged with mounting bracket  52  secured to structure  12 . Mounting bracket  52  includes spaced apart plate portions,  54  and  56 , each having openings through which hook portion  46  can pass. As shown, a cotter pin is used to prevent hook portion  46  from separating from mounting bracket  52 . Hook portion  48  is similarly engaged with mounting bracket  52 .  
         [0027]     Mounting bracket  52  is designed to be securely attached to structure  12  and to provide and easy way to install and remove ladder  10 . As illustrated, mounting bracket  52  comprises a right angle bracket designed for attachment to a typical dock but can be designed for securing ladder  10  to any desired structure such as a pool, boat, or the like. The hook and bracket structure is preferred but any structure may be used to attach ladder  10  to a structure. Moreover, while a separate mounting bracket is illustrated, a mounting flange of other structure may be integrated with link  14  in accordance with the present invention. Preferably, stabilization bar  50  is designed to work together with mounting bracket  52  to help provide a secure mounting arrangement such as by providing a balancing or offsetting function.  
         [0028]     Preferably, links  14 ,  16 ,  18 , and  20  comprise monolithic structures. That is, each link is preferably formed, by bending for example, from a bar or the like. However, each link can be assembled from plural pieces such as by welding, mechanical fastening, or joining, or the like. An exemplary assembly process includes forming each desired link so that each eye is sufficiently open to allow the eye to pass over its respective upwardly extending member. A suitable tool can then be used to close the eye so that is slidingly attached to the upwardly extending member.  
         [0029]     Preferred materials for fabricating the links of ladder  10  include aluminum, steel, and stainless steel, for example. Any material that provides the desired properties. such as formability, strength, and corrosion resistance, can be used. Preferably, ½ inch diameter round stock is used for links  14  and  16  while ⅜ inch diameter stock is used for links  18  and  20  (or any subsequent lower links). Generally, larger diameter stock is preferred for use on the links that are attached to or near the structure to which the ladder is attached (upper links). Lower links can be made from smaller diameter stock because these links do not need to be as strong/rigid as the upper links. That is, there is a larger bending force on the upper links when a person climbs the ladder.  
         [0030]     In use, ladder  10  can be attached to a structure such as a dock or the like and provided in the collapsed configuration. Preferably, a releasably connection is used to hold ladder  10  in the collapsed configuration. Such a connection may include a wire  58 , as shown in  FIG. 13 , clip, hook, breakable tie, or the like. The releasably connection functions to hold ladder  10  in the collapsed configuration until needed. That is, the releasably connection is preferably designed to release when someone such as a swimmer pulls on the lowermost rung of ladder  10  so that ladder  10  downwardly extends to the climbing configuration.  
         [0031]     The present invention has now been described with reference to several embodiments thereof. The entire disclosure of any patent or patent application identified herein is hereby incorporated by reference. The foregoing detailed description and examples have been given for clarity of understanding only. No unnecessary limitations are to be understood therefrom. It will be apparent to those skilled in the art that many changes can be made in the embodiments described without departing from the scope of the invention. Thus, the scope of the present invention should not be limited to the structures described herein, but only by the structures described by the language of the claims and the equivalents of those structures.