Patent Publication Number: US-RE49130-E

Title: Ladder attachment platform

Description:
STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT 
     This invention was made with Government support under Contract No. DE-AC09-96SR18500 awarded by the United States Department of Energy. The Government has certain rights in the invention. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to ladder attachment platforms. More particularly, the present application involves a ladder attachment platform that allows a user to stand at a location spaced from the front of the ladder. 
     BACKGROUND 
     Ladders are used to gain access to higher vertical locations. In some instances, a user will stand on the ladder to perform an activity or access a particular area. It is known to provide ladders with flat surfaces onto which a user may stand during use of the ladder so that the user is afforded with a wider and more comfortable standing surface. However, it is sometimes the case that a user may want to access an area that is offset from the ladder. Such flat, standing surfaces are not offset from the ladder for stability purposes to ensure that the ladder will not fall over. These surfaces only allow the user to face forward towards the ladder and are thus limited in application. Further, such flat, standing surfaces do not include handrails or other safety features. 
     Rail cars typically have one or more ladders located thereon. Aside from pulling rail cars, locomotives may push rail cars in certain instances. The pushing of rail cars requires a switchman to ride on the lead rail car to flag and provide watch for the locomotive engineer. Standard practice is for the switchman to ride on a ladder that is typically attached to the side of the lead rail car. The switchman must keep one hand on the ladder in order to firmly hold onto the ladder thus impeding his or her ability to operate an emergency brake, radio, or provide hand signals. Although minimally adequate for short trips, standing on the ladder of a lead rail car during long distance moves is not practical or safe. As such, there remains room for variation and improvement within the art. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth more particularly in the remainder of the specification, which makes reference to the appended Figs. in which: 
         FIG. 1  is a perspective view of a ladder attachment platform in accordance with one exemplary embodiment. 
         FIG. 2  is a right side elevation view of the ladder attachment platform of  FIG. 1 . 
         FIG. 3  is a front elevation view of the ladder attachment platform of  FIG. 1 . 
         FIG. 4  is a top plan view of the ladder attachment platform of  FIG. 1 . 
         FIG. 5  is a left side elevation view of the ladder attachment platform of  FIG. 1 . 
     
    
    
     Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the invention. 
     DETAILED DESCRIPTION OF REPRESENTATIVE EMBODIMENTS 
     Reference will now be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, and not meant as a limitation of the invention. For example, features illustrated or described as part of one embodiment can be used with another embodiment to yield still a third embodiment. It is intended that the present invention include these and other modifications and variations. 
     It is to be understood that the ranges mentioned herein include all ranges located within the prescribed range. As such, all ranges mentioned herein include all sub-ranges included in the mentioned ranges. For instance, a range from 100-200 also includes ranges from 110-150, 170-190, and 153-162. Further, all limits mentioned herein include all other limits included in the mentioned limits. For instance, a limit of up to 7 also includes a limit of up to 5, up to 3, and up to 4.5. 
     The present invention provides for a ladder attachment platform  10  that can be used in conjunction with a ladder  14  that provides a user platform  28  that allows a user to stand thereon and face multiple directions. The user platform  28  is spaced laterally away from the ladder  14  to afford the user with access to areas away from the ladder  14 . A handrail assembly  58  may be included to assist the user in maintaining balance on the user platform  28  during use. The handrail assembly  58  can be incorporated into a rail car  60  so that the user, who may be a switchman, can ride thereon and have one or more hands free in order to operate an emergency brake, radio, or provide flag signals. In other arrangements, the ladder attachment platform  10  can be associated with ladders  14  that are not incorporated onto rail cars  60  so that the user can access additional areas away from the ladder  14 . 
     One exemplary embodiment of the ladder attachment platform  10  is illustrated in  FIGS. 1-5 . The ladder attachment platform  10  includes a base  12  that may be arranged in a variety of manners. For example, a series of square tubular members can be attached to one another to form a generally open framework structure. Although described as being square tubular members, the components making up the base  12  can be variously arranged and may be for instance rectangular tubular members, circular tubular members, or solid members. In other arrangements, the base  12  can be a closed structure formed from a single piece so that it does not have an open framework structure. The base may be made of any material such as plastic, metal or wood in accordance with various exemplary embodiments. The base  12  may be arranged with respect to a ladder  14  so that a first side  40  of the base  12  faces the ladder  14 , and so that a second, opposite side  42  faces away from the ladder  14 . 
     The rail car  60  may include an end  68  that has a ladder  14  located thereon. The ladder attachment platform  10  can be attached to the ladder  14  in accordance with certain exemplary embodiments. The ladder  14  has a first side rail  16  and a second side rail  18  that may extend in a vertical direction  72  and can be spaced from one another in a lateral direction  26 . A plurality of rungs  20 ,  22 , and  24  may extend from the first side rail  16  to the second side rail  18  and can run in the lateral direction  26 . Any number of rungs can be present in the ladder  14  in accordance with different embodiments. The first and second side rails  16  and  18  may be positioned so that a first plane  30  extending through the first side rail  16  is parallel to a second plane  32  extending through the second side rail  18 . The first plane  30  and second plane  32  may each be perpendicular to the lateral direction  26 . As such, the first plane  30  and second plane  32  may each be perpendicular to the direction the rungs  20 ,  22  and  24  extend from the first side rail  16  to the second side rail  18 . 
     The base  12  may be attached to the ladder  14  in a number of manners. As shown, a first attachment member  36  and a second attachment member  38  may be attached to the base  12  and can be likewise attached to the ladder  14 . The attachment members  36  and  38  may be clevises and can be welded or otherwise permanently attached to the first side  40  of the base  12 . The first rung  20  may be positioned within the openings of the devises and pins can be inserted through the first and second attachment members  36  and  38  in order to effect attachment of the members  36  and  38  to the first rung  20 . As such, the attachment members  36  and  38  can be removably attachable to the first rung  20 . In other arrangements, a single attachment member  36  can be used and the second attachment member  38  need not be present. Also, although described as being clevises, it is to be understood that the attachment members  36  and  38  need not be clevises in other exemplary embodiments but may be variously arranged. For example, brackets or clamps can be used to attach the turnbuckle to the base  12  and ladder  14  instead of clevises  52  and  54  in accordance with other exemplary embodiments. The attachment members  36  and  38  can be attached to the first rung  20  so that they are capable of rotating thereon. As such, the attachment members  36  and  38  may be pivotally attached to the rung  20 . Alternatively, the sizing and pins extending through the attachment members  36  and  38  may be arranged so that the members  36  and  38  are not capable of rotating with respect to the rung  20  but are instead rigidly affixed thereto. The attachment members  36  and  38  may have a length or size that is not adjustable so that the attachment members  36  and  38  cannot be adjusted to vary the distance between the base  12  and the first rung  20  in some embodiments. In other embodiments, the attachment members  36  and  38  may be capable of being adjusted to vary this distance. 
     A turnbuckle  50  may also be incorporated into the ladder attachment platform  10  in order to help secure the base  12  in place and prevent rotation thereof. The turnbuckle  50  can be attached to both the base  12  and a second rung  22  of the ladder  14  that is higher than the first rung  20  in the vertical direction  72 . Although shown as having a single third rung  24  between the rungs  20  and  22  to which the turnbuckle  50  and first and second attachment members  36  and  38  are attached, any number of rungs may be located between these members in other embodiments. For example, from 2-5 rungs, from 3-8 rungs, from 4-10 rungs, or up to 15 rungs may be located between the rung attached to the turnbuckle  50  and the rung attached to the first and second attachment members  36  and  38 . Additionally, the rung attached to the turnbuckle  50  may be immediately adjacent the rung to which the first and second attachment members  36  and  38  are attached in other exemplary embodiments. 
     An eye may extend from the upper surface of the base  12  for use for attachment to the turnbuckle  50 . The turnbuckle  50  may include a clevis  52 . The clevis  52  can include a threaded stem that is received within a clevis-receiving member  56  of the turnbuckle  50 . The clevis  52  defines an opening  53  into which the eye of the base  12  can be positioned. A pin may be inserted through the clevis  52  and eye in order to retain the clevis  52  to the base  12 . The clevis  52  may thus be attached to the base  12  in a pivotal engagement. The other end of the turnbuckle  50  can include a clevis  54  that is arranged in a manner similar to the clevis  52 . The threaded stem of clevis  54  may be received within internal threading of the clevis-receiving member  56 . Additionally, an opening  55  defined by the clevis  54  can be positioned so that the second rung  22  of the ladder  14  is disposed through the opening  55 . A pin can be inserted through the clevis  54  and can contact the second rung  22 . With such an arrangement, the turnbuckle  50  is suspended on the second rung  22 . The attachment of the clevis  54  to the rung  22  may thus be a sliding attachment. However, sliding of the clevis  54  along the lateral direction  26  of the rung  22  may be prevented due to the fixing of the opposite clevis  52  to the base  12 . As shown, the openings  53  and  55  of the clevises  52  and  54  are not oriented in the same direction as one another but are instead rotated and oriented 90° to one another. However, in other arrangements the openings  53  and  55  may be oriented in the same direction as one another. Further, although shown as using clevises  52  and  54 , the turnbuckle  50  can be attached to the base  12  and rung  22  in other manners. The turnbuckle  50  can be attached to the base  12  at a location remote from the first side  40  so that the turnbuckle  50  attachment functions to prevent the base  12  from rotating about the first rung  20 . In some arrangements, the turnbuckle  50  can be attached to the second side  42  of the base  12 . As illustrated, the turnbuckle  50  is attached to an eye extending from the upper surface of the base  12  at a location that is proximate to the second side  42 . 
     The clevis-receiving member  56  can be rotated by the user in order to shorten or elongate the turnbuckle  50 . The clevises  52  and  54  are both attached by way of a threaded engagement to the clevis-receiving member  56 . As such, rotation of the clevis-receiving member  56  causes the threaded clevises  52  and  54  to move outward or inward with respect to the clevis-receiving member  56 . The turnbuckle  50  can thus be sized to a length in which the upper surface of the base  12  is horizontal with respect to the ground. Further, adjustability of the turnbuckle  50  allows the ladder attachment platform  10  to be used with ladders  14  having rungs variously spaced from one another. In some embodiments, the length of the turnbuckle  50  can be shortened or elongated when the turnbuckle  50  is attached to both the base  12  and the ladder  14 . In other embodiments, the turnbuckle  50  cannot be lengthened or shortened when attached to the base  12  and ladder  14 . Further, although shown and described as incorporating a turnbuckle  50 , the ladder attachment platform  10  need not include a turnbuckle  50  in accordance with other exemplary embodiments. 
     The base  12  may include one or more posts extending from the upper surface onto which a handrail assembly  58  is positioned. Although three posts are shown, any number may be used in other embodiments. Still further, no posts need be necessary in yet other exemplary embodiments. In this regard, the handrail assembly  58  may be integrally formed with the base  12 . The handrail assembly  58  can be made from tubular or solid members and may be a single component or may be multiple components that are attached to one another. The handrail assembly  58  extends upwards from the base  12  in the vertical direction  72 . 
     The ladder attachment platform  10  also includes a user platform  28  that is carried by the base  12 . The user platform  28  can be a solid plate or may be a grate in certain exemplary embodiments. Further, the user platform  28  may be a series of parallel beams or slats in yet other arrangements. The user platform  28  can be configured in any manner that allows a user to stand thereon. The user platform  28  may be square or rectangular in shape in certain arrangements. In yet other exemplary embodiments the user platform  28  can be variously shaped. The upper surface  34  of the user platform  28  may be provided with an anti-skid material or configuration to minimize the chance of slippage of the user when standing on the upper surface  34 . The user platform  28  may be located on the upper surface of the base  12 . In other exemplary embodiments, the user platform  28  can be located on the lower surface of the base  12  or can extend from a side of the base  12 . The user platform  28  may be integrally formed with the base  12  so that these two components are a single piece. In yet other arrangements, the user platform  28  may be removable from the base  12 . The user platform  28  may be permanently attached to the base  12 . In some exemplary embodiments, the user platform  28  is welded to the base  12  or bolted to the base  12 . 
     The handrail assembly  58  may be arranged adjacent the user platform  28  so as to define a portion of the perimeter of the user platform  28 . In this regard, the handrail assembly  58  may impede a user standing on the user platform  28  from exiting the user platform  28  in the direction towards the turnbuckle  50  or the first plane  30  or second plane  32 . The handrail assembly  58  can also be positioned with respect to the user platform  28  so as to impede a user on the user platform  28  from exiting the user platform  28  over the second side  42  of the base  12 . The handrail assembly  58  may be open so that the user is not impeded by the handrail assembly  58  when exiting other portions of the user platform  28 . For example, a portion of the user platform  28  can be located proximate to the first side  40  of the base  12 . The handrail assembly  58  may be open at this location so that the user can freely exit the user platform  28  across the first side  40  without being impeded by the handrail assembly  58 . Likewise, an end  44  of the base  12  may extend from the first side  44  to the second side  46 . The end  44  is located remote from the rail car  60  so that the end  44  is the farthest portion of the base  12  from the rail car  60  in the width direction  66 . An end  46  of the base  12  is located opposite from the end  44 . The handrail assembly  58  can be arranged so that a user on the user platform  28  can exit the user platform  28  over the end  44  without being impeded by the handrail assembly  58 . As such, in accordance with one exemplary embodiment, the perimeter of the user platform  28  may be defined by the handrail assembly  58 , the end  44  of the base  12 , and the first side  40  of the base  12 . The handrail assembly  58  may extend from 2 to 4 feet, from 3 to 5 feet, or up to 10 feet above the upper surface of the base  12  in the vertical direction  72 . The handrail assembly  58  may be removable from the base  12  for ease of attachment thereto. In other arrangements, the handrail assembly  58  is permanently attached to the base  12 . The handrail assembly  58  may be made out of aluminum in accordance with one exemplary embodiment. 
     Referring now to  FIGS. 3 and 4 , the relationship of the user platform  28  to the rail car  60  will be discussed. The rail car  60  has a longitudinal centerline  74  that runs in the length direction  70 . The user platform  28  may be positioned with respect to the rail car  60  so that the longitudinal centerline  74  does not run through the user platform  28 . As such, the entire user platform  28  may be spaced from the longitudinal centerline  74  in the width direction  66  in certain exemplary embodiments. Likewise, the ladder  14  may be spaced from the longitudinal centerline  74  in the width direction  66  in certain arrangements so that the longitudinal centerline  74  does not extend through the ladder  14 . The user platform  28  may be spaced from the ladder  14  in the width direction  66  so that no portion of the user platform  28  is located between the first plane  30  and the second plane  32 . However, it is to be understood that other arrangements are possible in which a portion of the user platform  28  is located between the first plane  30  and the second plane  32 . The first plane  30  extends through the first side rail  16  and the second plane  32  extends through the second side rail  18 , and the first and second planes  30  and  32  are perpendicular to one another in the width direction  66 . The user platform  28  may be positioned completely on one side of the first plane  30  in the width direction  66 , and no portion of the user platform  28  may be located on both sides of the first plane  30  in the width direction  66 . Still further, the user platform  28  may be arranged so that it is located completely on one side of the second plane  32  in the width direction  66  and so that no portion of the user platform  28  is located on both sides of the second plane  32  in the width direction  66 . However, it is to be understood that the aforementioned arrangements are only exemplary and that other positioning between the user platform  28  and the planes  30  and  32  are possible. 
     As illustrated, the rail car  60  has a first side  62  and a second side  64  that are opposite from one another in the width direction  66 . The ladder  14  and user platform  28  are located proximate to the first side  62 . An end  68  of the rail car  60  extends from the first side  62  to the second side  64 . The end  68  functions as the very front of the train when the locomotive is pushing the plurality of rail cars. The ladder  14  may be located on the end  68 , and the entire user platform  28  may extend beyond the end  68  in the length direction  70 . In other arrangements, a portion or all of the user platform  28  may be located rearward of the front end  68  in the length direction  70 . Further, the entire user platform  28  may extend completely beyond the entire ladder  14  in the length direction  70 . In yet other arrangements, the user platform  28  may be located in the length direction  70  on either side of the ladder  14 , or may be located on one side of the ladder  14  in the length direction  70  and located at the same location as the ladder  14  in the length direction  70 . 
     The entire user platform  28  may be located outboard of the first side  62  in the width direction  66 . In other exemplary embodiments, a portion of the user platform  28  is located outboard of the first side  62  in the width direction  66 , and a portion of the user platform  28  is located inboard of the first side  62  in the width direction  66 . As such, a portion or all of the user platform  28  may be located outboard of the rail car  60  in the width direction  66 . The location of the user platform  28  and other portions of the ladder attachment platform  10  may still be selected so that railroad clearances with respect to the width direction  66  and vertical direction  72  are satisfied such that the user platform  28  and other portions of the ladder attachment platform  10  do not contact tunnel walls, switches, or other items associated with rail traffic. The user may stand on the user platform  28  and can access a side ladder  76  that is attached to the first side  62  of the rail car  60 . The handrail assembly  58  is arranged so that access to and from the side ladder  76  and user platform  28  is not impeded. The user platform  28  allows the user to simply stand thereon and perform activities with both hands. Alternatively, the user may lean a portion of his or her body against the handrail assembly  58  for support while using one or more hands to do various activities. Further, the user can grasp the handrail assembly  58  and/or side ladder  76  with one or more hands for additional support when standing on the user platform  28 . The user platform  28  may be a stable surface that allows the user to remain in a normal standing position thereon with his or her hands free to operate an emergency brake, radio, or provide flag signals. 
     Although shown and illustrated as being used with a rail car  60  in a train, it is to be understood that the ladder attachment platform  10  need not be associated with a ladder  14  of a rail car  60 . For example, the ladder attachment platform  10  can be used with ladders  14  employed in various applications. For example, the ladder attachment platform  10  can be made of lighter materials and attached to a tower ladder  14 . The ladder attachment platform  10  may find utility upon being used in conjunction with ladders  14  on a chimney, radio tower, or water tank. Such use allows a user to extend the working surface of the ladder  14  so that other areas next to the ladder  14  can be accessed. The ladders  14  associated for use with the ladder attachment platform  10  are contemplated as being fixed ladders. As such, the ladders  14  are generally permanently fixed to the structure to which they are used. A portable ladder, on the other hand, can be moved from place to place by the user and is not permanently associated with any particular structure. However, it is to be understood that the ladder attachment platform  10  can be used with portable ladders  14  in certain exemplary embodiments and is not limited for use with a fixed ladder  14 . 
     The ladder attachment platform  10  may be arranged so that the base  12  is attached to the rungs of the ladder  14  and no other portion of the rail car  60  or ladder  14 . In this regard the base  12  may not be attached or contact the side rails  16  and  18  of the ladder  14 . Further, the base  12  need not contact any other portion of the rail car  60  and thus the only points of contact between the base  12  or any other portion of the ladder attachment platform  10  is at the rungs of the ladder  14 . The points of contact in this regard are between the first and second attachment members  36  and  38  and the first rung  20  and between the turnbuckle  50  and the second rung  22 . However, in accordance with other exemplary embodiments, portions of the rail car  60  and ladder  14  in addition to or alternatively to the rungs may contact the base  12  or other portions of the ladder attachment platform  10 . 
     It is to be understood that as used herein the terms attached, attachable, attachment and so forth are to be construed liberally unless otherwise noted. For example, the terms may define two components that are integrally formed with one another or that are separate components that are connected to one another through the use of welding, adhesives, mechanical fasteners, or other means. Further, the terms may define two components that may be capable of pivoting, sliding, or moving with respect to one another upon the use of these terms as their attachment may be pivoting attachment, sliding attachment, etc. Further, the terms may also mean that the two components contact one another. However, in some arrangements an intervening piece such as a bracket or fastener can be between the two components so that they do not actually contact one another. As such, the foregoing terms mean that the two components contact one another in some embodiments, and the foregoing terms also mean that the two components do not contact one another in other embodiments. 
     While the present invention has been described in connection with certain preferred embodiments, it is to be understood that the subject matter encompassed by way of the present invention is not to be limited to those specific embodiments. On the contrary, it is intended for the subject matter of the invention to include all alternatives, modifications and equivalents as can be included within the spirit and scope of the following claims.