US1496459A - Folding extension ladder - Google Patents

Description

F. W. GILBERT FOLDING EXTENSION LADDER June 3 1924.

Filed Nov. 4. 1920 2 Sheets-Shan 2 @Hoz/neg Patented .lune 3, 1924 STATES FRANCIS W. GILBERT, F TOLEDO, OHIO.

FOLDING EXTENSION LADDER.

Application filed November 4, 1920. Serial No. 421,636.

To all whom t may concern.' Y

Be it known that I, FRANCIS W. GILBERT, a citizen of the United States, residing at Toledo, in the county of Lucas and State of Ohio, have invented certain new and useful Improvements in a Folding Extension. Ladder, of which the following is a specii'ication.

This invention relates to ladders, and particularly to folding extension ladders for use in and about buildings to facilitate the work in building, painting and decorating,

an important feature of the invention beingA to provide a ladder of such character 'that it may be quickly set.y up when required and easily taken down, and which is adaptable to the ground or surfaces having irregularities therein.

A further object of the invention is to provide a ladder of this character which shall possess rigidity when in use, and which .may be quickly andjeasily adjusted to various heights when desired.

With these objects in View, together with others which will appear as the description proceeds, the invention resides in the novel construction, combination and arrangement of parts, all as will be described more fully hereinafter, illustrated inthe drawings and particularly pointed out in the claims.

In the drawing:

Figure 1 is a side elevation of a ladder constructed in accordance with the invention Figure 2 is a front elevation of the ladder,

Figure 3 is an enlarged detailed sectional view taken substantially upon line 3 3 of Figure 1,

Figure 4 is a similar view taken on line 4-4 of Figure 1, and

Figure 5 is a side elevation showing the ladder in its folded position.

In carrying out the invention, I provide base members or laterally adjustable ladder sections, to support vertically disposed vertically adjustable ladder sections or members, and planking is to be supported at its ends by the vertically adjustable members. The vertically adjustable members have rungs therein to support the planking, and it v is obvious that adjustment in the height of the planking may be made by resting the ends thereof upon those rungs of the ladder sections near the top. In addition, adjustment may be made by moving the' vertically adjustable ladder sections up or down as de sired. In the event that Van irregularity exists between the spaced ladder members, or if the ground or support for the spaced or laterally adjustable members varies in height, the planking for the support of the workmen may be made to assume true horizontal position, either by placing the ends of lthe planking upon those rungs of the ladder sections which are in the same horizontal plane, or by adjusting the vertical ladder sections of one or both extension ladders until the desired level of the planking has been obtained.

Referring now to the drawings, the eXtension ladder comprises a pair of base members 7, in the form of ladders, having rungs 8 therein. These base members are pivotally connected together at their upper ends so as to be capable of being brought together in substantiallyclose parallel relation, as shown in Figure 5, or spread apart and disposed at an angle to each other as shown in Figure 1. To permit of these functions, one of the base members 7 is provided upon each of its stiles, near the upper end, with a connecting body member 9 having a yoke l0, while each of the 'stiles ofthe opposing leg is provided with a connecting body having a plate 11 to lit between two similar plates of the yoke. The yoke and plate 11 are provided with registering openings to receive connecting pins or pivots in the lform of bolts 12. The upper ends of the base members are thus held firmly together, yet the said legs may be swung to spread or` closed position when desired. Each of the bolts 12 has swivelled thereto a bracket or guide 13, the said bracket being disposed upon the inner faces of the yoke members and being of such size as to loosely accommodate the stiles 14 of the vertically adjustable ladder member or section. Each of the stiles 14 may be provided in one edge with notches 15 to be engaged by pawls 16 pivotedupon the upper ends of the stiles of one of the base members 7, and it is obvious, therefore, that vertical numerous adjustments of the ladder section 14 may be secured. In the present instance, one edge of each of the stiles of the ladder 14 is provided with a thin metallic plate having the spaced notches therein to be engaged by the pawls.

rlliepawls 16 are pivoted to the upper end of one of the base members or ladder-sections 7 so that they may be swung into an inclined position, wherein they may engage the notches 15 of the extension member 14 when the base members are unfolded as shown in F ig. 1. The pawls may be swung to inoperative position between the stiles of the pawlcarrying section when the sect-ions of the base are folded together as shown in Fig. 5. In the unfolded position of the base the pawls are disposed in extensioirholding position, while in the other position of the base, the pawls are` disposed in extension-releasing position. Furthermore, it should be noted that because of the pivotal connection between the pawls and the base section these pawls may be released from engaging position, even when the base sections are unfolded.

Each pair of stiles of the opposing ladder members 7 support between Vthem a bracket or guide 17, similar in size and construction to the bracket or guide` 13, and the brackets 17 and 13 are maintained in vertical alignment. The Stiles of the ladder section 111 are received in the said brackets and maintained in proper vertical position. The brackets 17 are connected at each side with a link 18, the said links be ing pivoted at their inner ends to the said bracket, and at their outer ends to the stiles of the ladder members 7. This construction enables the members 7 to be adjusted toward or away from each other without disturbing the true vertical alignment of the brackets 13 and 17. By reason of the fact that the brackets 13 and 17 are spaced apart, the ladder section 14 will be rmly held against lateral movement, and each of the bracket members contributes to the support of the ladder member 14.

l claim:

1. A folding extension ladder comprising a foldable base of laterally adjustable ladder-sections, pairs of vertically spaced guides carried by said base, an extension member comprising a vertically adjustable ladder-A section mounted to slide in said guides betweemthe sections of the base, and pawls pivoted to the upper end of one of the laddersections of the base for holding said eXtension member in adjusted position, said pawls being movable for assuming an e-Xtensionwith notches throughout its length, and

pawls pivoted upon the upper end of one of the ladder-sections of the said base and movable for engaging certain of the notches when the base is unfolded and disengaging the notches when the base is folded.

in testimony whereof l alix my signature.

rnANors w. GILBERT.

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