Patent Application
20140027203
Ladders are often made using thin sheet metal or plastic siderails to decrease weight, though ladders can still be quite heavy. Moving the ladders between locations may require putting the ladder in a horizontal position, gripping the siderails with the hand and lifting the ladder. The siderail edge contacts the hand along an edge line and much of the ladder's weight is supported along that line. This can be very uncomfortable and for people who work with ladders on a regular basis can be a source of fatigue on the job.
In one embodiment a ladder lift system is described comprising a ladder including a rail with a web and flanges and a grip with a longitudinal axis, a top surface and gripping surfaces where the top surface includes a slot parallel with the longitudinal axis configured to engage one flange of the ladder rail. The gripping surfaces may be contoured to conform to at least a portion of a user hand.
In another embodiment a resilient handle with a longitudinal axis for transporting a ladder is described comprising two end surfaces perpendicular to the longitudinal axis and a first surface parallel to the longitudinal axis. The handle may also include a second surface comprising the balance of the handle surface with raised portions and recessed portions that correspond to a hand gripping the handle about the longitudinal axis. A channel parallel to the longitudinal axis may open to the first surface and to the two end surfaces where the channel is configured to mate with one edge of the ladder.
Patents and publications related to ladder grips include US Patent Publications 20080011547, 20020046904, 20020189902 and 20100263189 and U.S. Pat. Nos. 5,511,285, 4,754,858, 5,207,364, 6,189,752 and 5,058,789.
Ladders are well known to those skilled in the arts and is a common tool used by homeowners and tradesmen.
Portions of ladder 10 are shown here for clarity. An entire ladder assembly can include a number of rails in different configurations including extension ladders, folding ladders, scaffold ladders and many others. Ladder 10 may encompass any of these configurations.
A gripping surface or contoured surface 28 may comprise the balance of the surface of ladder grip 18. Gripping surface 28 may have contours 30 corresponding to user hand 16. Contours 30 of grip 18 may include raised or convex portions and recessed or concave portions of surface 28 forming ridges and valleys. Contours 30 may increase the contact area and comfort of user hand 16 when lifting ladder 10. Alternatively, gripping surface 28 may not be contoured.
Ladder grip 18 may be formed from any workable or mold castable material and may be extruded. Ladder grip 18 may be a resilient plastic material such as a foam or nylon or other polymer. Ladder grip 18 may be homogenous, monolithic and/or uniform. For the purposes of this disclosure monolithic is defined as being made of one piece of a single material.
Pushing ladder grip 18 onto rail 12 or, conversely, sliding edge 12C into slot 26, may bias, elastically bend or deflect grip material proximate to slot 26 and as a result ladder grip 18 may be frictionally retained by ladder rail 12. This may allow grip 18 to be removed from ladder 10 once it is moved and reattached to a different ladder for transport. Biasing proximate grip material may result in the material applying a normal force to the surface of rail 12. Alternatively, ladder grip 18 may be permanently fixed, adhered or bonded to ladder 10.
The described system and assemblies are examples for the purpose of illustration and are not to be used as limitations. Any suitable configuration or combination of components presented, or equivalents to them that perform a similar function will fall within the scope of this disclosure.
