US3490558A

US3490558A - Stepladder scaffold apparatus with elevating working platform

Info

Publication number: US3490558A
Application number: US731013A
Authority: US
Inventors: James M Foley
Original assignee: JAMES M FOLEY
Current assignee: JAMES M FOLEY
Priority date: 1968-05-22
Filing date: 1968-05-22
Publication date: 1970-01-20
Anticipated expiration: 1987-01-20

Description

J. M. FOLEY Jan. 20, 1970 STEPLADDER SCAFFOLD APPARATUS WITH ELEVATING WORKING PLATFORM Filed May 22, 1968 2 Sheets-Sheet 1.

INVENTOR JAMES M. FOLEY ATTORNEYS Jan. 20, 1970 J. M. FOLEY 3,490,558

STEPLADDER SCAFFOLD APPARATUS WITH ELEVATING WORKING PLATFORM Filed May 22, 1968 2 Sheets-Sheet 2 JAMES M. FOLEY BY SAG/000 we! Sh 11m ATTORNEYS United States Patent 3,490,558 STEPLADDER SCAFFOLD APPARATUS WITH ELEVATING WORKING PLATFORM James M. Foley, 59 Sunset Road,

Fail-field, NJ. 07006 Filed May 22, 1968, Ser. No. 731,013 Int. Cl. E06c 7/16 U.S. Cl. 182-103 11 Claims ABSTRACT oF THE DISCLOSURE Scaffold apparatus in which a stepladder is mounted upon a mobile base and provided with an elevating working platform movable along a supporting frame opposite to the ladder steps. A winch is provided to raise the working platform. and to operate a material lifting unit. An extension frame permits raising of the platform above the top of the stepladder. A second scaffold unit may be employed together with the first and a bridge plank to provide a larger scaffold. A railing provided for the elevating platforms and the bridge plank may be assembled and disassembled in different configurations to accommodate the type of scaffold desired. Accessory trays and work holders increase the versatility of the apparatus.

BACKGROUND OF INVENTION This invention relates to working platform or scaffold apparatus and more particularly is concerned with a mobile scaffold unit which may be employed singly or in pairs by one or more workmen to provide a wide diversity of services.

It has heretofore been proposed to provide mobile scaffold units, such as an extension ladder supported upon a mobile base. It has also been proposed to provide lifting units upon ladders, such as a lifting frame for fruit baskets or an elevating hopper which may be lowered and dumped. In the building or construction arts a need has nevertheless existed for asimple, compact, vertically adjustable working platform unit which may be readily moved about and utilized by one man and which is constructed to permit two men to employ the unit cooperatively and to permit the units to be utilized in pairs to provide larger scaffolds when desired. An ordinary stepladder alone is not a comfortable, safe, or adequate place to work. A workman must climb up and down the ladder each time it is necessary to relocate the ladder or to carry up materialsQIt is difficult and awkward to support materials on the ladder, andit'is almost impossible to work at the top of the ladder',because there is nothing to hold on to. A working platform of substantial area is what is needed, one that can be moved up and down but readily fixed in position. I I v BRIEF SUMMARYOF THE INVENTION It is accordingly a principal object of. the present invention toprovide improved working platform or scaffold apparatus which fulfills the foregoing needs.

A more specific object of the invention is to provide such apparatus which perinits a workman to function comfortably and safely at any one of a Wide range of selected working heights,.which permits material to be lifted and supported, which may be easily moved about and set up, which permits two or more men to work in unison, and which is capable of assembly with similar units to provide an extended scaffold.

Briefly'stated, a preferred embodiment of the present invention includes a stepladder mounted upon a mobile base and arranged to be collapsedagainst the base or erected for use; The frame of the ladder opposite to the 3,490,5 5 8 Patented Jan. 20, 1970 stepsupporting rails supports an elevating working platform which maybe raised to any selected height and fixed in position. An adjustable lifting unit for lifting and supporting materials is also provided, both the lifting unit and the Working platform being raised by a winch sup ported upon the ladder. An extension frame permits raising of the working platform above the top of the step: ladder. The platform is provided with a removable railing which may be assembled in different configurations de pending upon whether the apparatus is to be used as a single unit or in pairs in conjunction with a bridge plank to provide an enlarged scaffold.

BRIEF DESCRIPTION OF THE DRAWINGS The foregoing and other objects, advantages, and features of the invention and the manner in which the same are accomplished will become more readily apparent upon consideration of the following detailed description of the invention taken in conjunction with the accompanying drawings, which illustrate preferred and exemplary embodiments, and wherein:

FIGURE 1 is a perspective view illustrating a unit of the apparatus of the invention ready for use;

FIGURE 2 is a somewhat diagrammatic perspective view illustrating the employment of a pair of units of the invention in conjunction with a bridge plank for providing a larger scaffold;

FIGURE 3 is a fragmentary perspective view illustrating details of a joint between the bridge plank and a Working platform associated with one of the units of FIG- URE 2;

FIGURE 4 is a somewhat diagrammatical perspective view illustrating the use of an extension frame which permits the working platform to be raised above the top of the stepladder; and

FIGURE 5 is a fragmentary perspective view illustrating details of the extension frame.

DETAILED DESCRIPTION OF THE INVENTION Referring to the drawings, and initially to FIGURE 1, in a preferred embodiment the apparatus of the invention comprises a stepladder 10 supported upon a rectangular mobile base 12 having casters 14 at the corners thereof, the casters being of the conventional type which may swivel or be locked against any movement. The stepladder comprises a pair of spaced rails 16 interconnected by a plurality of parallel flat steps 18. A frame opposite to the steps 18 includes parallel uprights 20 and transverse frame members 22 extending between the uprights. The tops of the uprights 20 are pivotally connected at 24 to the top panel 30 of the stepladder by means of pivot ally connected

hinge plates

26 and 28 fixed to the up rights 20 and the rails 16, respectively. The top panel is fixed to the rails 16. The bottoms of 'the'uprights are pivotally connected at 32 to the mobile base 12 by means of brackets 34 fixed 'to-the baseand supporting the pivot pins 32 which extend through'the uprights"20 The bottoms of the rails 16 aredetachably fastened to the base 12 at 36, the fastenings-includingbolts' and-nuts, for example, which are secured to angleibrackets'38 fixed to the base. The pivot pins 32 and the lower extr en'iities' of uprights 20 are spaced above therifiat upper surface of the base 12 so that if the fastenings 36fiare released, the rails 16 may be collapsed against the uprights 20, by virtue of the pivotal connections 24 at th'e top' of the ladder, and the entire ladder .may then :be collapsed against the base 12 (turning counterclockwise '-'if1-FIG- URE l, for example); The ladder may ha ve the usual transverse braces such as the collapsible links 39 attach side thereof. As seen from the side 'the 'ladder assufn'es the usual inverted V-shape when-erected (or iA-shap'e,

if the braces 39 are considered). The base 12 extends a considerable distance beyond the uprights 20 (to the right in FIGURE 1), which in the form shown is approximately half the distance between the bottoms of the uprights 20 and the rails 16. This extension of the base provides additional fiat surface for supporting tools, paint cans, and other working implements, but its principal purpose is to provide stability for the working platform 40.

The working platform 40 has a flat floor which is of large enough area to encompass the feet of a man and thus to support a man comfortably and safely. For ex ample, the floor of the platform may be at least eighteen inches in depth projecting away from the uprights 20 by two feet in width extending between the uprights 20. The platform projects as a cantilever from a pair of rectangular carriages or sleeves 42, being rigidly secured thereto by braces 44. By virtue of this construction and the length of the sleeves, which embrace the uprights 20, tilting movement of the platform is prevented. Sleeves 42 are preferably metal channels which may 'be provided with a plurality of internal rollers 43 engaging comple mentary surfaces of the uprights 20 to permit smooth reciprocative movement of the platform along the uprights. Each of the uprights is provided with a series of holes 46 into which a pin 48 may be inserted. through each sleeve to fix the position of the platform along the uprights, the pins being held captive upon the sleeves by chains 50. In the form shown the uprights 20 are spaced farther apart than the tops of rails 16 and are located beyond the ends of the top panel 30 of the ladder. The actual surfaces upon which the sleeves ride may be constituted by metal channels bolted to underlying wooden frame members of the ladder proper.

The platform 40 is provided with a removable railing comprising horizontal elements 52 and their vertical posts 54.'The posts are received within wells 56 attached to the floor of the platform and may be locked therein by pins or set screws (not shown). The railing comprises Ts or elbows 58 which permit the parts to be assembled and disassembled. As shown assembled in FIGURE 1 the horizontal components of the railing define a U- shaped portion with the bight remote from the stepladder and the opening between the legs closed by a restraining member, such as a chain 60, which may be detached from the railing. A tray or other receptacle 62 may be removably fastened to the railing by means of

hooks

64 and 66 which embrace the horizontal and vertical railing components.

The working platform 40 may be raised or lowered by means of a winch or hoist 68 supported upon the top panel 30 of the ladder beneath its lower surface. The winch may comprise a cable 70, which may assume the phantom line position 72 to engage the platform 40 at 74 adjacent to the ladder frame. The coupling at 74 may be effected by means of a hook or split ring on the cable engaging an eye upon the platform. The cable may be passed over a pulley or cable guide 76 at the top of the ladder, extendingthereto from a winding drum 78 turned by a'handle 80 through the intermediary of a conventional gear train (not shown). The handle may be supported by bracket plates 82 upon one of the rails 16 and may be removable.

A suitable winch is described in the applicants prior Patent No. 2,990,160, issued June 27, 1961. To raise or lower the platform the locking pins 48 are removed from the h oles 46 and the crank 80 is turned in the appropriate direction. Then the pins are reinserted.

In the preferred form the apparatus of the invention further comprises a lifting unit 84 for lifting and holding'work material or implements. This unit may include a work bench top 86 having an upraised lip 88 at one side thereof and capable of being fixed to the sub-frame 90 of the liftin the position illustrated in FIGURE 1, or the reverse position, by means of removable fasteners, such as bolts 92. The lifting sub-frame may comprise a pair of uprights constituted by parts 94 and .96, parts 94 telescoping into hollow sleeve parts 96 for pre-lifting height adjustment and being fixable relative thereto by removable pins 98 which pass through holes in parts 96 and engage anyone of a series of holes in part 94. The uprights 94-96 extend through openings in the top panel 30 of the ladder and pass through corresponding sleeves 106 supported beneath the top panel of the ladder. The bottoms of the uprights 94-96 are joined by a transverse member 100 adapted to engage cable 70 at 104 by means of a coupling arrangement similar to that discussed with respect tov the working platform 40. The work holder 84 may thus be raised or lowered to a convenient height and fixed in position by locking the winch or by inserting pins through sleeves 106 and uprights 94-96.

A pair of units of the type illustrated in FIGURE 1 may be employed together as shown at 10A and 10B in FIG- URE 2 to provide an enlarged scaffold. For this purpose a bridge plank 108 is placed between and coupled to the

respective platforms

40A and 40B after the platforms have been positioned at a selected height. The bridge plank comprises a suitable flat deck with depending truss-type reinforcements 112 (FIGURE 3) and may be utilized with additional horizontal railing elements coupled to the

horizontal railing elements

52A and 52B associated with the

platforms

40A and 40B. It will be noted that the latter horizontal railing elements have been assembled with their posts so that the opening between the legs of each U- shaped railing portion faces the opposite railing portion, whereby assembly of railing elements 110 with the

railings

52A and 52B provides a large enclosed work space above the platforms and the bridge plank. FIGURE 3 illustrates the manner in which the bridge plank 108 may be coupled to each platform, the bridge plank being provided with a lip 114 which overlaps the associated platform and receives pins or bolts 116 passing through the lip and corresponding openings 118 (see FIGURE -1) of the platform. If desired, the units 10A and 10B may be turned 90 respectively clockwise and counterclockwise in FIGURE 2 and the bridge plank 108 mated with side edges of the working platforms.

FIGURE 4 illustrates the use of an extension frame 120, which in general is constructed like the frame of the stepladder, the bottom of the extension frame mating with the top of the ladder frame. As shown in FIGURE 5, the extension frame may have uprights 122 constructed like the uprights 20 and provided with depending tongues 124 which enter corresponding openings at the top of the upright channels 20 so as to telescope within the members 20. Frame has transverse frame members 126 like frame members 22. A pulley or other cable guide 128 may be supported upon the uppermost transverse frame member 126, being braced by rods 130, so that the cable 70 may be passed in front of pulley 76, behind extension frame 120, over the pulley 128 and then downwardly in front of the extension frame to engage the platform 40 as shown in FIGURE 4. The platform may thus be raised above the top panel 30 of the ladder. v

The apparatus of the present invention provides a mobile working platform which is compact, stable, safe, and exceptionally versatile. A single unit of the invention serves the function of multiple ladders, dollies, and scaffolds employed heretofore in an attempt to perform the same functions. One man may safely perform alone work normally requiring more than one man. Yet,- two men may readily work in unison, one standing upon the work ing platform 40, for example, and the other upon the steps 18 of the ladder, which are in no way encumbered by the working platform. A worker may stand at the level of the very top of the ladder and yet have the safety of the large area and railing of the working platform. The extension of the base 12 beyond the bottoms of uprights 20 is sufficient to ensure stability of the apparatus and is preferably at least as great as the projection of the plat form 40 from the ladder frame. The unit is compact;

enough to be moved about without disassembly but can be readily collapsed or disassembled when desired.

While a preferred embodiment of the invention has been shown and described, it will be apparent to those skilled in the art that modifications can be made without departing from the principles and spirit of the invention, the scope of which is defined in the following claims. For example, instead of employing a cable to lift the subframe 90, the sub-frame may have a gear rack fixed thereto and driven by a pinion turned by a handle supported on the top panel 30 of the ladder.

The invention claimed is:

1. Working platform apparatus comprising a stepladder having a pair of sides pivotally connected adjacent to the top thereof so that the sides may be moved together to collapse the ladder and may be moved apart to erect the ladder and form an inverted V-shape, one of said sides including a pair of spaced rails having a series of steps extending laterally therebetween, the other of said sides being a frame having a pair of spaced rails with a series of rungs extending laterally therebetween and having an extension thereof with a pair of spaced rails and transverse rungs and with means for supporting the extension upon said other side so as to extend upwardly beyond the pivotal connection of said sides of said ladder, a working platform having means for fixing it to said frame for projection therefrom at any one of a plurality of positions therealong, including positions above and below said pivotal connection of said sides, and base means for supporting said ladder and including a portion extending substantially horizontally from the bottom of said frame in a direction away from said one side of said ladder to stabilize said ladder when said platform is in use, whereby a user of the apparatus may have free access to the working platform by climbing said steps, may work upon said platform with stability ensured by said base, and may work in unison with another user standing upon said steps.

2. The apparatus of claim 1, said portion of said base means extending beyond the bottom of said frame a distance of the order of the projection of said platform from said frame.

3. The apparatus of claim 1, said portion of said base means being supported upon casters and said base means having another portion extending substantially horizontally from the bottom of said one side and supported upon casters.

4. The apparatus of claim 1, the bottom of said frame being pivotally connected to said base means and the bottom of said one side having releasable means for fixing said one side upon said base means, whereby said releasable means may be released to permit said stepladder to be collapsed against said base means.

5. The apparatus of claim 1, said stepladder having a winch supported thereon, said winch having a lifting cable with means for connecting it to said platform for elevat ing the same when the winch is operated.

6. The apparatus of claim 1, said stepladder havmg a top panel and supporting work holder for vertical movement toward and away from said top panel and having means for fixing the position of said work holder relative to said top panel.

7. The apparatus of claim 6, said stepladder having a winch supported thereon adjacent to said top panel with a cable adapted to lift said work holder.

8. Working platform apparatus comprising a pair of units each including a stepladder having a pair of sides pivotally connected adjacent to the top thereof so that the sides may be moved together to collapse the ladder and may be moved apart to erect the ladder and form an inverted V-shape, one of said sides including a pair of spaced rails having a series of steps extending laterally therebetween, the other of said sides being a frame having a pair of spaced rails with a series of rungs extending laterally therebetween, a working platform having means for. fixing it to said frame for projection therefrom at any one of a plurality of positions therealong, and base means for supporting said ladder and including a portion extending substantially horizontally from the bottom of said frame in a direction away from said one side of said ladder to "stabilize said ladder when said platform is in use, and further comprising a bridge plank with means for coupling the opposite ends thereof to said platforms, respectively, whereby a user of the apparatus may have free access to the platforms and plank by climbing the steps of said units and may work upon said platforms and plank stably, alone or in unison with other users, who may stand on said steps.

9. The apparatus of claim 8, each of said platforms having a railing supported thereon, and means for coupling the railings of the respective platforms for constituting a railing above said bridge plank.

10. The apparatus of claim 8, each of said stepladders being supported upon a mobile base.

11. The apparatus of claim 8, each of said stepladders having a work holder supported above the top of the stepladder and vertically adjustable with respect thereto.

References Cited UNITED STATES PATENTS 107,225 9/1870 Claflin 182-103 976,240 11/1910 Winkler 182-103 1,269,463 6/1918 Langille 182-119 1,384,694- 7/1921 Foster 182-127 2,237,543 4/1941 Berchem 182-149 2,798,652 7/1957 Easton 182-17 2,978,062 4/1961 Di Camillo 182-1 3,128,842 4/1964 Satrum 182-149 3,139,154 6/1964 Ewald 182-129 3,176,794 4/1965 Evans 182-17 3,207,261 9/1965 Petersen 182-129 3,208,555 9/1965 Fry 182-129 3,344,885 10/1967 Rasmussen 182-103 FOREIGN PATENTS 621,777 6/1961 Italy.

REINALDO P. MACHADO, Primary Examiner US. Cl. X.R. 182-129, 127