Rolling or skidding platform ladder

Abstract

A rolling or skidding platform ladder 1 is provided that has a platform ladder part 3 and an undercarriage part 5. The undercarriage part 5 carries ground engaging parts 21 to enable rolling or skidding of the ladder 1. The platform ladder part 3 has legs 7/9 which are raisable with the platform ladder part 3 to elevate the bottom of the legs 7/9 spaced from the ground when the platform ladder 1 is to be rolled or skidded. The undercarriage part 5 comprises a lever arm 29 that is pivoted thereto in a see-saw manner so as to extend generally parallel with the ground. One end of the lever arm 29 is for co-operating with the ladder part 3 to raise at least two legs of the ladder part 3 relative to the undercarriage part 5 so that the rolling ladder 1 can then be rolled or skidded without the at least two raised legs engaging the ground.

1 . A rolling or skidding platform ladder (hereinafter referred as rolling ladder) comprising a platform ladder part and an undercarriage part, said undercarriage part carrying ground engaging parts to engaging with the ground during rolling or skidding of the rolling platform ladder,
 said platform ladder part having legs for engaging with the ground when the ladder is to be climbed upon, said legs being raisable with the platform ladder part from the undercarriage part to elevate the bottom of the legs spaced from the ground when the platform ladder is to be rolled or skidded,   said undercarriage part comprising a lever arm pivoted thereto by a pivot in a see-saw manner so as to extend generally parallel with the ground, one end of the lever arm being for co-operating with the ladder part to raise at least two legs of the ladder part relative to the under carriage part when the opposite end of the lever arm is moved in a direction downwardly, so said rolling ladder can then be rolled or skidded without the at least two raised legs of the ladder part engaging the ground.   
   
   
       2 . A rolling ladder as claimed in  claim 1 , wherein the raised legs of the ladder part can be moved to engage the ground by a person standing on the ladder part using their weight to cause the lever arm to swing and the opposite end of the lever arm to be raised by swinging in a direction upwardly. 
   
   
       3 . A rolling ladder as claimed in  claim 1 , wherein the undercarriage part is generally of rectangular shape in plan view and is at a lowermost part of the ladder part, and extends between sides of the ladder part and front and rear legs of the ladder part, and directly above generally horizontally extending leg braces of the legs of the ladder part which are adjacent the ends of the legs of the ladder that engage the ground and which interconnect front and rear legs of the ladder part,
 said undercarriage part carrying vertically downwardly extending pins fixed thereto which penetrate apertures associated with the leg braces, said pins carrying respective ground engaging wheels or skids at their ends closest to the ground.   
   
   
       4 . A rolling ladder as claimed in  claim 1 , wherein said undercarriage part has the lever arm positioned generally midway between the two sides of the ladder part, and adjacent thereto a further lever arm pivoted to the undercarriage part by a further pivot, said pivot being at a front of the ladder part and said further pivot being at a rear of the ladder part, said further lever arm being also pivoted in a see-saw manner to said undercarriage part so as to extend generally parallel to the ground, one end of the further lever arm being for co-operating with the ladder part to raise the other two legs of the ladder part relative to the under carriage part when the opposite end of the further lever arm is moved in a direction downwardly. 
   
   
       5 . A rolling ladder as claimed in  claim 4 , wherein the opposite ends of the lever arm and further lever arm, are interconnected by a common pivot, so when one is moved downwardly or upwardly, it will cause the other to move in a corresponding direction. 
   
   
       6 . A rolling ladder as claimed in  claim 5 , wherein the opposite ends of the lever arm and the further lever arm carry a person's foot engaging surface,
 said lever arm and said further lever arm being pivoted to each other generally midway between a front and a rear of the undercarriage part, whereby a user can place his foot within the ladder part between the front legs and rear legs and press either one of the foot engaging surfaces with his foot to cause both the lever arm and the further lever arm to move in a direction downwardly.   
   
   
       7 . A rolling ladder as claimed in  claim 3 , wherein there are four vertically downwardly extending pins, each being positioned on the undercarriage part to be adjacent a respective one of four legs of the ladder part, so that there will be a wheel or a skid adjacent each of the four legs. 
   
   
       8 . A rolling ladder as claimed in  claim 6 , wherein the lever arm and the further lever arm are pivoted to each other and to the front and rear of the undercarriage so that when the lever arms are moved to pass each other, during moving in a downward or upward direction, there will be a flexing of a front and a rear of the undercarriage part in a direction outwardly of the undercarriage part, said flexing providing a bias force to cause snap movement of the lever arm and further lever arm as the lever arm and further lever arm move to pass each other. 
   
   
       9 . A rolling ladder as claimed in  claim 8  wherein the undercarriage part is fabricated from elongate metal. 
   
   
       10 . A rolling ladder as claimed in  claim 1 , wherein the ladder part carries a slidable sheet like member,
 said slidable sheet like member being supported in a generally horizontal plane by generally horizontal extending guide rails under the upper tread surface of the ladder part, and wherein the slidable sheet like member can slide along said rails so that one side thereof is positioned outwardly of the steps of the ladder, whereupon the one side can be swung downwardly to overlie one or more treads of the ladder and to act as a visual indicator that the rolling ladder is closed for use.   
   
   
       11 . A rolling ladder as claimed in  claim 10 , wherein the slidable sheet like member has fingers extending from side edges thereof, said fingers being received in a channel in the guide rails and being at both ends of the slidable sheet like member, and such that when the slidable sheet like member is slid so that the one side thereof is positioned outwardly, the fingers remaining in the channels will act like a hinge to allow the slidable sheet like member to swing thereabout to overlie the one or more treads.