US2788930A - Ladder attachment - Google Patents

Description

April 16, 1957 R. D. PALS LADDER ATTACHMENT Filed Nov. 25, 1955 INVENTOR. R c/ n20 D; PAL QM HTTQRIIEVJ nite rates ?ate LADDER ATTACHMENT Richard D. Pals, Seattle, Wash. Application November 25, 1955, Serial No. 549,046 8 Claims. (Cl. 228-60) This invention relates to an attachment for ladders that is especially advantageous for use in connection with long, heavy ladders, which may or may not be of the extension types. More specifically, the invention relates to a novel form of roller attachment for ladders, that is designed for application to their upper ends for rolling contact with a wall surface against which the ladder may be leaned, to facilitate the movement of the ladder either horizontally or vertically therealong.

It is the primary object of this invention to provide a roller attachment of the above stated character, that is readily applicable to a ladder and which is equipped with one set of rollers whereby the upper end of the ladder may be supported in the clear of the wall for easy raising or lowering, and with another set of rollers for supporting it for easy horizontal travel along the wall.

It is a further object of the invention to provide means that may be controlled from ground level for selectively utilizing either of the sets of rollers as provided for vertical or horizontal movement of the ladder.

Still another object of the invention resides in those details of construction that permit adjustment of the device to adapt it for attachment to ladders of ditferent widths.

Further objects of the invention reside in the details of construction and combination of parts, and in their mode of use, as will hereinafter be fully described.

In accomplishing the above mentioned and other objects of the invention, I have provided the improved details of construction, the preferred forms of which are illustrated in the accompanying drawings wherein:

Fig. 1 is a front elevation of the upper end portion of a ladder equipped with an attachment means embodied by the present invention.

Fig. 2 is a side View of the same, showing the ladder as supported from a vertical wall surface by the rollers which provide for its vertical adjustment.

Fig. 3 is a view of the ladder and attachment device as seen from directly above its upper end.

Fig. 4 is a vertical section of the ladder and attachment device taken on line 4-4 in Fig. 1.

Fig. 5 is a perspective view of the upper end portion of the ladder as equipped with the present attachment device.

Referring more in detail to the drawings:

In the various views, -16 designates the upper end portions of the opposite longitudinal members or rails of a typical ladder, and 11 designated what ordinarily would be the top rung of the ladder. While the present attachment device may be used with ladders of various types, it is primarily intended for use with long and hard to handle ladders, especially of the extension types.

The present attachment device comprises a horizontal cross-shaft 12 that extends through and is rotatably supported near its opposite ends by angle iron brackets 13-13; these brackets being short lengths of angle iron that are extended along and are secured by bolts 14 to the back side at their upper ends of the rails 10-10.

Rotatably mounted on the outer end portions of the cross-shaft, are wheels 15-15, preferably of hard rubber, that are held on the shaft by washers and cotter keys 16-17 applied to the shaft ends in the manner well shown in Fig. 5. In the normal use of the ladder, the wheels 15-15 serve to support it by contact with the vertical wall surface against which the ladder is leaned, and make possible an easy vertical adjustment thereof, particularly in the raising or lowering of an extension section.

Welded or otherwise fixed to the shaft 12, at the insides of the rails 16-10 of the ladder, and perpendicular to the shaft, are stub axles 20-20, extended in the same direction, and on these stub axles wheels 21-21 are rotatably mounted and held in place by washer and cotter key 22-23 applied to the axles as best shown in Fig. 5. The wheels 21-21 are also preferably of hard rubber and of greater diameter than the wheels 15-15. Ordinarily, when the wheels 15-15 are engaged with a wall surface, as in Fig. 2, the cross-shaft 12 is held against rotation and in such position that the stub axles 20-20 extend directly away from the wall, as seen in Fig. 4, thus placing the wheels 21-21 in the clear of the wall; the shaft 12 being yieldingly held in this position against rotation by the tension of a coiled spring 25 that is fixed at one end to the top rung of the ladder and at its other end is attached to the lower end of an arm 26 that is welded or otherwise fixed to the cross-shaft and which extends radially therefrom. The arm 26 is located close to the inside of one of the rails 10, as noted in Fig. 1 and ordinarily is held in the downwardly directed position shown in Fig. 4.

Should it be desired to move the ladder horizontally along a wall against which it is leaning, the shaft 12 is then rotated to such extent that the rollers 21-21 are carried into wall contacting position as shown in dotted lines in Fig. 4, and in doing this, the ladder is caused to be moved slightly away from the wall surface and the rollers 15-15 are moved into the clear thereof.

For the purpose of rotating the cross-shaft 12 to bring the rollers 21-21 into ladder supporting contact with the wall surface, I provide a rope or cable 30 which extends from a position of access at the lower end of the ladder, upwardly along that side rail 10 adjacent which the lever arm 26 is located. At the upper end of the ladder, the cable or rope passes over a pulley 32 that is mounted in a bracket 33 that is bolted to the ladder rail 10, and then extended downwardly from the pulley and is fastened to a yoke 34 which, in turn, is fastened by a pivot pin 35 to the outer end of lever arm 26. When the operator, who may be standing on the ground at the foot of the ladder pulls on the cable, the lever arm 26 is caused to swing upwardly and forwardly, as indicated by the arrows in Fig. 4, thus to rotate the cross-shaft and cause the rollers 21-21 to be brought into their functional position, that is, into ladder supporting and also rolling contact with the vertical wall surface. In this position they hold the ladder and rollers 15-15 clear of the wall surface.

With the ladder so supported by rollers 21-21, it may be rolled horizontally along the wall while leaning against it. When pull on the cable is released, the spring 25 acting on the lever arm, rotates the shaft 12 to swing the rollers 21-21 into the clear and allow the rollers 15-15 to again engage the wall.

While 1 have shown the shaft 12 as being yieldingly held in the position shown in Fig. 5 by means of the spring 25 attached under tension to arm 26, it is quite possible to apply spring means in various other ways. For example, a coiled spring might be coiled about the shaft and secured under torsion by attaching its opposite Patented Apr. 16, 1957 ends to the shaft and ladder rail. Rotation of the shaft would be effected in a manner similar to that shown.

In order that the attachment may be applied to ladders of difierent widths, the cross-shaft 12 is centrally divided and the adjacent ends thereof are telescopically contained within a sleeve 40. The sleeve and the shaft ends are formed along opposite end portions with a succession of diametrically directed holes 41 for a selective application of bolts 42 thereto as a means whereby the shaft ends may be joined at different distances of spacing thus to extend or shorten the effective length of the cross-shat to suit the spacing of the ladder rails Iii-19 to which the device is to be applied.

Devices of this kind are easy to apply; easy to use, and are relatively inexpensive, and they make possible an easy raising or lowering of the ladder along a wall, or for its movement along a wall.

Having thus described my invention, what I claim as new therein and desire to secure by Letters Patent is:

l. The combination with a ladder having laterally spaced opposite side rails; a shaft mounted transversely of and by said rails adjacent their upper ends for limited axial rotation, 21 pair of wheels mounted axially on said shaft for rolling contact with a wall surface against which the ladder is leaned, stub shafts extended in the same direction and perpendicularly from said shaft, a second pair of wheels mounted on said stub shafts, and a manual means for rotatably adjusting said shaft to cause the second pair of wheels to be brought into rolling contact with the Wall surface for support and lateral movement of the ladder as leaned against the wall surface.

2. The combination with a ladder having paired, laterally spaced opposite side rails; a cross-shaft mounted by said rails, horizontally and'transversely of the ladder near its upper end, paired wheels mounted axially on the opposite end portions of said shaft for rolling contact with the wall surface against which the ladder is leaned, a pair of stub shafts extended in the same direction from opposite end portions of said shaft and perpendicularly thereto, a pair of wheels mounted for rotation on saidv stub shafts, means for axially, rotatably adjusting said shaft to cause the second mentioned pair of rollers to be swung from a position disengaged from the wall surface to a position in rolling contact therewith and whereby the first set of rollers is moved outwardly from the wall surface.

3. T he combinationv of claim 2 wherein the means for rotatably adjusting said shaft comprises a lever arm that is fixed, thereto and extended. radially therefrom.

V posite side 4. The apparatus of claim 2 wherein the means for rotatably adjusting said shaft comprises a lever arm that is fixed to the shaft and extended radially therefrom, a pulley wheel mounted on a rail of the ladder, and a rope attached to said lever arm and passed over said pulley, and extended therefrom to a position accessible to a person at the foot of the ladder for the actuation of the lever arm to rotate the shaft.

5. The apparatus of claim 4 including also spring means acting against the lever arm to yieldingly retain the shaft at a position of rotatable adjustment at which the second pair of rollers is held clear of the wall surface.

6. A ladder comprising paired, laterally spaced oprails, a cross-shaft mounted by said rails, horizontally and transversely of the ladder and near its upper end, paired rollers mounted co-axially of the shaft on its opposite end portions for rolling contact with the wall surface against which the ladder is leaned, a pair of stub shafts extended equally from opposite end portions of said shaft in the same direction and perpendicular to the shaft, :1 pair of rollers mounted on said stub shafts, a lever arm extended radially from the shaft, a spring attached under tension to the arm and to the ladder to yiedlingly retain the shaft at a position of rotatable adjustment at which the second mentioned set of rollers are held clear or" the wall surface against which the ladder is learned, a pulley wheel mounted on the ladder rail above the lever arm, and a cable attached to said arm and extended upwardly and over the pulley and then downwardly for manipulation by a person at the foot of the ladder for rotation of the shaft for moving the second set of rollers against the Wall surface and moving the ladder and first mentioned. set of rollers clear of the wall surface.

7. The combination of claim. 6, wherein the said cross shaft comprises telecopical'ly adjustable sections joined end to end to provide for an adjustment in overall length to accommodate it to ladders of various widths.

8. The combination of claim 6 wherein the said shaft is rotatably mounted at its opposite ends, in brackets, and said brackets are equipped for fixed mounting on the opposite side rails of a ladder, and said shaft comprises telescopically joined sections providing for changes in adjustment in length of the shaft to accommodate it to ladders of different Widths.

No references cited.

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