US 2882003 A
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Description (OCR text may contain errors)
April 14,1 1959 v H. S'QFFLER 2,882,003
STEPLADDER JACK Filed Mamma-l, 195e ,drive/Vey United AStates Patent STEPLADDER JACK Hugh A. Stiilier, Indianapolis, Ind.
Application March 31, 1958, Serial No. 725,017
2 Claims. (Cl. 248-226) This invention relates to a collapsible device normally termed a ladder jack which may be adjustably secured to the top step of a step-ladder so as to extend rearwardly or forwardly or even centrally thereof.
The ladder jack may be employed with step-ladders of different widths of top steps and is primarily intended to serve as a foundation for a work surface to be laid thereover such as a plaster mortar board; a brick-layers mortar board; and for any surface to support members employed by a worker, such as when he is doing ceiling work.
The device may be so attached to a step-ladder that the workman may work on the same step-ladder, or he may apply it to one step-ladder as a workbench foundation and then stand on an adjacent ladder.
The purpose of the invention is to permit the workman to have his tools and materials up where he can reach them instead of having to climb up and down the stepladder frequently.
One particular form of the invention is described herein in reference to the accompanying drawing, in which:
Fig. l is a view in side elevation and partial section of the upper portion of a step-ladder to which the invention is applied; and
Fig. 2 is a transverse section on the line 2-2 in Fig. l.
In the present showing, the step-ladder is of the usual and well known type having the steps 11 between two side rails 12 and 13, with a top wider step 14, and the supporting legs 15 and 16, the legs 12, 13 and 15, 16 being hinged by suitable brackets 17 and 13 to the underside of the top step 14.
The jack is comprised of two channel members 19 and 20 each having a top leg 21, an under leg 22 shorter than the top leg 21, and an intervening integral web 23.
These two channel member 19 and 20 are interconnected by means of a pair of links 24 and 25, the link 24 being pivotally connected to the leg 19 by means of a rivet 26; the link 25 being pivotally connected to the leg 20 by means of a rivet 27; and these two links 24 and 25 are pivotally interconnected at their ends removed from the members 19 and 20 by means of a rivet 28.
The under leg 22 for each member 19 and 20 is provided with a series of spaced apart holes 29 which are screw-threaded, each carrying a thumbscrew 30. Preferably the end of the thumbscrew 30 which is presented between the legs 21 and 22 carries a swivel base 31. The base 31 serves two purposes, namely to provide an area of contact with the underside of the top step 14 and also to prevent the thumbscrew 30 from losing out of the hole 29.
The jack constructed as above described, is applied to the step 14 by bringing the members 19 and 20 up over opposite ends of the step 14 as indicated in Fig. 2 particularly, so that the leg 21 in each instance will be on the topside of the step 14 and the leg 22 in each instance will be on the underside. The members 19 and 20 may be moved forwardly andrearwardly across the step `1'4 to give the desired projection thereof from either the frontside or thebackside of the step 14, here lshown as Aextended to the forwardlimit. The screws 30 then appearing under the step 14 are turned to bring theirbases 31 snugly against the underside of the step 14 so as to hold the members 19 and 20 securely and rigidly in their extended positions.
In placing the members 19 and 20 along the ends of the step 14, the links 24 and 25 will be inclined yone with the other to a degree depending upon the length of that step 14. For wide steps, the links 24 and 25 may approach a straight line whereas, when the steps are narrower, the links 24 and 25 will be angularly positioned one in relation to the other and to the members 19 and 20 as indicated in Fig. 2.
When the device is to be removed from the step 14 for transportation `or storage, the thumbscrews 30 are released, and the two members 19 and 20 are brought one toward the other to have the links 24 and 25 fold respectively between the legs 21 and 22 to have the two mem- 'bers 19 and 20 come into abutment one with the other to come into the smallest overall dimensions of the combined members.
When the jack is applied to the upper step 14 as indicated in the drawing, these members 19 and 20 form under girders or rails to support a platform separately made and laid lover the members 19 and 20. Since such platforms generally utilized by plasterers or brick-masons are made to have a smooth upper surface with two under rails, these rails may straddle the members 19 and 20 and prevent slippage of the platform laterally of the jack. The weight of the board plus the weight of the materials placed thereon will prevent the board from sliding longitudinally of the members 19 and 20. In the position of the jack indicated in Figs. l and 2 of the drawing, the workman may utilize the steps of the ladder 10 and have the jack extending forwardly from him as he stands on the ladder. When the members 19 and 20 are shifted to positions where parts of them overhang the ladder step 14 to the rear, then another ladder 10 may be brought up along the side of the first ladder 10 as a means for supporting the workman who then will have the jack at his side to support whatever he may want to have at hand.
Therefore it is to be seen that I have provided an exceedingly simple ladder jack which may be applied to any ladder having members with overhanging ends or edges to which the jack may be attached removably, and the jack itself collapsed into a compact carrying condition. While I have herein Ishown and described my invention in the one particular form, it is obvious that structural changes may be made without departing from the spirit of the invention, and I therefore do not desire to be limited to that precise form beyond the limitations which may be required by the following claims.
l. A jack for a stepladder having a step with exposed ends, comprising a pair of channel members leach with a top and bottom leg and an intervening integral web; a plurality of screw members screw-threadedly passing through said bottom legs; and linkage means rockably secured to and tying together said channel members adjafcent common ends thereof and removed from the location of said screw members; said channel members adapted to straddle said step ends with the legs extending over top and bottom sides of the step, the top legs being adapted to compressively engage with the step by advancing said screw means through the lower legs against the under step side.
2. The structure of claim l in which said linkage means consists of a pair yof links, one each pivotally conneeted by an end portion to the upper leg of each channel member, and both links pivotally interconnected together at their other end portions; said links permitting the channel members to be spaced apart from an initial position of one channel member lying in contact by leg edges along the other With the `links carried fully between the legs, to maximum spaced apart positions wherein said links extend in approximately a straight line between the channel members.
References Cited in the le of this patent UNITED STATES PATENTS Becker June 24, 1958 FOREIGN PATENTS Great Britain of 1902 Germany May 23, 1903