Ladder
First Claim
1. A platform ladder comprising two elongate ladder sections having feet at one end and an upper end, the upper end of each section being hinged to an upper rail, a platform pivotally secured to one ladder section below the upper end and adapted to hook against the other ladder section, and stays interconnecting each side of the ladder sections, each of the stays comprising a bracing bar hinged to each ladder section at positions that enable the ladder to assume an operative position with the ladder sections assuming an erect A shaped profile with the platform extending between the ladder sections to define a standing platform, and a folded position in which the ladder sections fold one against the other, and the platform, the upper rail and the stays fold within the plane defined by the ladder sections,the platform being coupled to the other ladder section by at least one platform stay whereby as the ladder sections are parted from the folded configuration the platform stay controls lowering of the platform until it hooks against the other ladder section when the sections are fully parted to assume the operative position, anda retarder being positioned between the platform and the platform stay to retard the relative movement and slow down the engagement of the platform with the other ladder section.
1 Assignment
0 Petitions
Accused Products
Abstract
A platform ladder comprising two elongate ladder sections having feet at one end and an upper end, the upper end of each section being hinged to an upper rail, a platform pivotally secured to one ladder section below the upper end and adapted to interconnect with the other ladder section, and stays interconnecting each side of the ladder sections whereby when the ladder is in an operative position with the ladder sections assuming an erect A shaped profile with the platform extending between the ladder sections to define a standing platform, the ladder sections, upper rail and stays, define a four bar linkage.
18 Citations
7 Claims
-
1. A platform ladder comprising two elongate ladder sections having feet at one end and an upper end, the upper end of each section being hinged to an upper rail, a platform pivotally secured to one ladder section below the upper end and adapted to hook against the other ladder section, and stays interconnecting each side of the ladder sections, each of the stays comprising a bracing bar hinged to each ladder section at positions that enable the ladder to assume an operative position with the ladder sections assuming an erect A shaped profile with the platform extending between the ladder sections to define a standing platform, and a folded position in which the ladder sections fold one against the other, and the platform, the upper rail and the stays fold within the plane defined by the ladder sections,
the platform being coupled to the other ladder section by at least one platform stay whereby as the ladder sections are parted from the folded configuration the platform stay controls lowering of the platform until it hooks against the other ladder section when the sections are fully parted to assume the operative position, and a retarder being positioned between the platform and the platform stay to retard the relative movement and slow down the engagement of the platform with the other ladder section.
- 4. A platform ladder comprising two elongate ladder sections having feet at one end and an upper end, the upper end of each section being hinged to an upper rail, a platform pivotally secured to one ladder section below the upper end and adapted to hook against the other ladder section, and stays interconnecting each side of the ladder sections, each of the stays comprising a bracing bar hinged to each ladder section at positions that enable the ladder to assume an operative position with the ladder sections assuming an erect A shaped profile with the platform extending between the ladder sections to define a standing platform, and a folded position in which the ladder sections fold one against the other, and the platform, the upper rail and the stays fold within the plane defined by the ladder sections, the upper railing including interfitting sections that form a closed loop to surround the user.
Specification