None.
1. Field of the Invention
The present invention is generally related to a rope ladder facilitating escape from a building during an emergency.
2. Description of the Related Art
Presently known rope ladders are made of soft textile belts sown together to form side rails and rungs. Several deficiencies are noteworthy. Rails and rungs twist and deform when the weight of a person is applied onto the rungs of the ladder. Known rope ladders hang close to or against the building, thus providing a narrow gap there between which prevents the user from properly stepping onto each rung of the ladder. As such, known rope ladders are difficult to use, thus extending the time required to traverse the length of the ladder and slowing escape from a building.
An object of the present invention is to provide a rope ladder with support attachments that allows the user to easily, reliably and properly step onto each rung of the rope ladder. The object of the invention is achieved by the technical features of the design.
The present invention, namely, a rope ladder with support attachments, includes a ladder hook allowing the ladder to be hung onto a building and a rope ladder body fixed to the hook. The rope ladder further includes a pair of vertically disposed and parallel flexible belt rails having a plurality of rigid rungs disposed between and attached to the belt rails in a perpendicular fashion. A support attachment is separately fixed onto the back surface of each belt rail at the joint between belt rails and rung in a paired and symmetrical fashion. The design of the present invention ensures that rope ladder and building are separated by the support attachments, thus allowing the user to step onto the rungs along the ladder.
Support attachments are of a folding design whereby each includes a base plate fixed to the joint including belt rail and rung along the rope ladder and a spacer plate articulated with respect to the base plate by way of a pivot pin. The pivot pin resides within a torsion spring, the force of which is sufficient to automatically and outwardly open the spacer plate until contact occurs between a stop along the spacer plate and a pair of bosses along the base plate. When openly deployed, each spacer plate forms an internal angle slightly larger than 90 degrees with respect to the rungs. This arrangement prevents the spacer plate from closing when a user steps on the rung. The foldable nature of the support attachments allows them to be closed when the rope ladder is coiled, thus reducing the space required for storage.
The hook includes a U-shaped hook body and two L-shaped hooks disposed about and attached thereto. The U-shaped hook body has a horizontal bar located at each end of the vertical bars comprising the U-shaped structure. Each L-shaped hook comprises a vertical bar and a horizontal bar, the latter having two bolts fixed and projecting there from. The horizontal bars along the hook body have a plurality of through holes which align with the bolts projecting from the L-shaped hook so as to facilitate adjustment to the spacing between rope ladder and building during use. Bolts along the L-shaped hooks are aligned with and inserted through the holes along the horizontal bars of the U-shaped hook body. Thereafter, butterfly nuts are screwed onto the bolts so as to secure the L-shaped hooks to the U-shaped hook body. The adjustability provided by the U-shaped hook body allows the present invention to be adapted to a variety of wall thicknesses and structures. Support attachments are either attached to each belt rail and rung joint along the rope ladder or assembled in a paired arrangement equally spaced every third or fourth rung.
Rungs are comprised of an aluminum alloy, in order to avoid deformation of the rope ladder when supporting the weight of a user, and have a fire-retardant textile cloth outer wrap.
The primary advantage of the present invention is that the rope ladder maintains its ladder shape and sufficient spacing from the structure onto which it is attached so as to allow the user to traverse the length of the rope ladder in a safe manner.
The invention will now be described in more detail, by way of example only, with reference to the accompanying drawings, in which:
A more detailed description of the present invention is provided below in combination with the attached drawings.
Referring now to
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One support attachment 4 may be assembled either onto each joint formed between belt rails 2 and rungs 3 or onto selected rungs 3 including repeating patterns such as every third or fourth rung 3.
Rungs 3 are preferred to be composed of an aluminum alloy material that is lightweight but sufficiently strong to support the weight of a user and having a round cross-section within the stepping region of the rung 3 and a flat cross-section where the rung 3 is attached to the belt rails 2. The rigid nature of the rungs 3 prevents deformation thereof, thereby facilitating climbing. A layer of fire-retardant braided textile may be wrapped around the exterior of the aluminum alloy rungs 3. Fire-retardant bands are sown together with nylon threads to enhance the friction force between rungs 3 and bands so as to properly secure the bands to the rungs 3.
Proper use of the rope ladder includes the following steps. The user adjusts the width of the hook 1 by positioning the bolts 123 within the appropriate through holes 112 so that the vertical elements along the U-shaped hook body 11 contact the outwardly disposed surface of a wall or structure and the vertical bars 122 contact the inwardly disposed surface of the same wall or structure. Thereafter, butterfly nuts 13 are tightened to fix the hook 1 to the structure and the ladder body is lowered. Spacer plates 42 within support attachments 4 are automatically opened by the torsion springs 44. The spacer plates 42 contact the wall or structure, thereby maintaining a suitable space between wall or structure and the rungs 3 and belt rails 2, thus allowing the user to step onto each rung 3 while avoiding contact with the wall or structure.
Number | Date | Country | Kind |
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03261042.4 | Aug 2003 | CN | national |
This application claims priority to PCT Application No. PCT/CN03/00878 filed on Oct. 21, 2003, which is hereby incorporated in its entirety by reference thereto.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/CN03/00878 | 10/21/2003 | WO | 2/7/2006 |