GB594684A - Improvements in step ladders - Google Patents

Abstract

594,684. Step ladders. CASLAKE, N. C. May 14, 1945, No. 12047. [Class 20(ii)] A step ladder comprises side frames 1 each consisting of a single length of metal tube joined at its ends by a metal foot 2, sheet metal treads 3 supported on at least two metal straps, one joining the two front tubes and the other, the two rear tubes of the side frames, and a pivoted tubular metal stay 10 comprising a single length of tube part of which is shaped to form a foot which, to avoid rocking, bears on the floor at each side but is clear of the floor in the centre. The ends of the straps are of semicircular shape to engage the tubes of the side frames and are fixed to the tubes by screws. The treads, the corners of which are cut away to engage round the tubes, have their edges bent over to form flanges which are bent to embrace the straps. Two additional straps may join the tubes at each side of the ladder. The treads are formed with an embossed pattern to prevent the feet slipping. Each of the upper ends of the tube forming the stay 10 is fixed in a bracket B pivoted at 17 to the rear tube of the corresponding side frame. The edge 16a of each bracket is shaped to engage round its rear tube, to prevent the stay from opening too far. The ladder may narrow slightly from top to bottom. In a modification, the stay 10 is combined with radius rods for limiting its outward movement, the stay is of rectangular form and its upper limb engages in slotted straps on the back of each rear tube of the side frames.. The radius rods are pivotally mounted at one end to an upper tread and at the other end to the stay. When the stay is closed the upper limb moves down in the slots in the straps to allow the radius rods to fold flat against the side frames. According to the Provisional Specification the side frames are formed from separate tubular members the upper ends of which are joined by a metal angle bar or by the upper tread.