Field of Search:
182/36,37,38,39,150,13-15 187/7
Claims:
I claim
1. In a hanging scaffold apparatus, a cantilever member comprising:
2. A hanging scaffold apparatus movable on a roof section of a building comprising:
3. The scaffold apparatus of claim 1 wherein said tandem wheel train is further characterized as comprising a frame connected to one end of said cantilever member, said frame rotatably supporting tandem spaced wheels, a pivot shaft longitudinally supported on said frame between said tandem spaced wheels, and said means for supporting said wheel hingedly connected to said pivot shaft.
4. The scaffold apparatus of claim 3 wherein said wheel support being further characterized as being an upright member, the end thereof formed to hingedly engage said pivot shaft.
5. The scaffold apparatus of claim 4 wherein the wheel support means is further characterized as having means on said upright member for adjustably positioning said vertically spaced wheel.
6. The scaffold apparatus of claim 2 wherein said wheel support being further characterized as being an upright member, the end thereof formed to hingedly engage said pivot shaft.
7. The scaffold apparatus of claim 6 wherein the wheel support means is further characterized as having means on said upright member for adjustably positioning said vertically spaced wheel between said track means.
8. The scaffold apparatus of claim 2 wherein said tandem wheel train is further characterized as comprising a frame connected to one end of said cantilever member, said frame rotatably supporting tandem spaced wheels, a pivot shaft longitudinally supported on said frame between said tandem spaced wheels, and said means for supporting said wheel hingedly connected to said pivot shaft.
9. The scaffold apparatus of claim 8 wherein said wheel support being further characterized as being an upright member, the end thereof formed to hingedly engage said pivot shaft.
10. In a hanging scaffold apparatus, a cantilever member comprising:
11. In a hanging scaffold apparatus movable on a roof section of a building comprising:
Description:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to scaffold apparatus and more particularly to a hanging scaffold.
2. Description of the Prior Art
The scaffold apparatus of my invention is intended for use on what is generally called sheet metal buildings, particularly in the construction thereof and in erecting the metal sheeting which form the wall of the building. Such buildings are usually extensive in length and erecting the sheeting to the frame members piece by piece is a job which can be considerably shortened in time required and consequently a substantial saving in the construction costs thereof. Since scaffolding is required to provide means to reach the top of the wall frame, the prior art that I am aware of has been to build a scaffold on the bed of a wheeled trailer which is hooked to a truck or tractor to move the trailer from position to position as the sheeting wall progresses. The principal disadvantage in rendering a scaffold device mobile in this manner is that the construction site is almost always in an unfinished state, being uneven and covered with debris which is usually present around new construction. Consequently, the trailer carrying the scaffold riding over such rough terrain alongside the building frame will rock from side to side, tilting the scaffold superstructure to such an extent endangering its tipping over. To prevent such hazards, the prior art practice has been to level the building site adjacent the building frame and remove the debris from time to time which is an additional labor cost in the construction of such a building.
The object of my invention is to provide a scaffold apparatus which is constructed to hang from tracks provided on the roof rafters and movable thereon as the sheeting work progresses and being independent of the building site. I am aware of prior art disclosing scaffolds hanging from parapets of buildings and roof rafters. provided with rails for movement. However, the disadvantages of such prior art apparatus is that since the scaffold structure is very heavy, its supporting structure on the parapet or roof will have to be sturdy to resist such a torsion strain. The strain caused by the weight of the scaffold will be of such magnitude that the supporting structure will have to be constructed with such strength and solidity that it becomes uneconomical to use this method of supporting a scaffold apparatus.
SUMMARY OF THE INVENTION
My invention provides new and novel means for connecting a hanging scaffold to a track means. My invention resides in providing a hinge connection between the wheel train of the scaffold apparatus which rides on the track and the cantilever extending beams from which the scaffold pole depends. The hinge connection between the wheel train and the scaffold structure prevents the transmission of a torsion force caused by the turning moment of the weight of the scaffold structure laterally offset from its support from being transmitted to the track. This allows the construction of the wheel train supporting the scaffold structure and the track device to be constructed of light weight material and of smaller dimension, thereby enabling the assembling of the apparatus on top of the building frame by manual labor rather than by crane means. The hinge connection of the scaffold apparatus also enables the outward pivotation of the scaffold structure and movement of the scaffold apparatus along the building as the work progresses, by manual handling.
Other objects and advantages of my invention will become more apparent after a more careful study of the following detailed description taken together with the accompanying drawings wherein is illustrated a preferred embodiment of my invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of the scaffold apparatus of my invention shown mounted on a rafter frame member of a building, shown in part;
FIG. 2 is a detail view of a portion of the diagonal foundation abuttment bar showing the gear drive for its longitudinal movement;
FIG. 3 is a front view of the scaffold apparatus of this invention, the scaffold structure is broken showing the part thereof connected to the cantilever beam;
FIG. 4 is a section detail of the clamping means for connecting the track base to the building rafter frame member;
FIG. 5 is a side view of the triad wheel train device in operative relation with the track in section illustrating the hinge connection between the wheel train device and the cantilever beam which is shown broken in part; and
FIG. 6 is a front view of the traid wheel train device shown in operative relation with the tracks which are shown fragmented, sectioned along lines 6--6 of FIG. 5.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings wherein is illustrated a preferred embodiment of my invention, reference numeral 10 designates the scaffold apparatus of my invention in its entirety. In FIGS. 1 and 3, I illustrate a scaffold structure 12 which is a basic scaffold structure suitable to carry support planks across horizontal bar members. The illustrated scaffold structure 12 comprising scaffold poles 14 and 16 braced to form the rigging thereof will be referred to throughout this specification. It should be understood, however, that any type scaffold structure may be used in the operation of my invention.
The scaffold apparatus 10 of my invention comprises a track device 18 having an upper rail 20 and a lower rail 22 supported in space relation by an elongated triangular frame 24. Triangular frame 24 is supported from rafter beams 26 (FIG. 1) to rafter beams 28 (FIG. 3) along the length of the building on hipped plate members 30 which are connected to base members 32 anchored to the flanges 34 of rafter beams 26 and 28. The connection between plate member 30 and base member 32 is pivotably adjustable by means of a slotted bolt hole 36 provided in plate member 30 to compensate for the difference in inclines of different roof designs on which base member 32 is connected. I show base member 32 connecting the flange 34 of rafter beam 26 by means of clamp members 38. By loosening bolt means 40 which pass through their respective holes and slots, hipped plate members 30 supporting triangular frame section 24 may be pivotally adjusted to position rails 20 and 22 thereof in a vertical plane. I prefer to connect the triangular frame 24 of track device 18 of my invention to plate member 30 by providing clamp brackets 42 and 44 at each distal end of hipped plate member 30 formed to receive therein longitudinal spar members 46 and 48, respectively, of triangular frame 24 and secured therein by cap members 50 and 52 bolted thereto. Accordingly, longitudinal sections of triangular frames 24 may be added end to end as best shown in FIG. 3, by connecting the terminal end of one triangular frame section to the end of succeeding triangular frame sections, the abutting ends of the frame sections being fitted and secured to a single set of clamp brackets 42 and 44 mounted on the same plate member 30.
Each cantilever beam structure 54 is preferably formed in a triangular cross-section from tubular members 56 connected by a rigging of spar members 58. One end of cantilever beam structure 54 is angled and provided with an end plate 60. Referring now to FIGS. 5 and 6, a vertically positioned longitudinal plate 62 is the terminal end of end plate 60 and is connected to the terminal ends of bottom tubular members 56. A second vertically positioned longitudinal plate 64 is provided laterally spaced from longitudinal plate 62 between which are rotatable mounted bottom track wheels 66 on axle shafts 68 connecting longitudinal plates 62 and 64. Spacer bars 70 and 72 are connected to longitudinal plates 62 and 64 such as by welding and provided with holes 74 to receive a pivot shaft 76. I further provide in longitudinal plate 62 a cutaway 78 to prevent interference with the hinge action of the wheel train which is designated generally by the numeral 80.
The apex wheel 82 of the triad or triangular positioned wheel train is mounted for rotatable movement on a shaft stud 84 which is formed integral with vertical plate 86. Vertical plate 86 is also provided with a threaded collar 88. Plate 86 is slideably movable between vertically positioned hinge plate 90 and channel member 92 which forms a part thereof. The bottom end of plate 90 is provided with a horizontally positioned trunion member 94 and is angled to position the trunion 94 between longitudinal plates 62 and 64 and between spacer bars 70 and 72 so that upon being aligned with holes 74 in spacer bars 70 and 72, pivot shaft 76 may be inserted therethrough to form the hinge connection between the cantilever beam structure 54 and wheel train 80. The top end of hinge plate 90 is provided with a bearing collar 96. The threaded shaft of crank handle 98 passes through bearing collar 96 and the threaded end thereof engages threaded collar 88 of vertical plate 86 so that by rotating crank 98, apex wheel 82 of wheel train 80 may be raised and lowered to engage or disengage track 20 of track device 18.
I provide on the cantilever beam structure 54 connecting links 102 (FIG. 1) depending from the bottom side thereof to which may be connected scaffold poles 14 and 16. The scaffold structure 12 comprises a pair of spaced pole pairs 14 and 16 depending from cantilever beam structure 54 hingedly connected to wheel train device 80 as described. Accordingly, for each scaffold structure, two cantilever beams 54 are provided hingedly connected to separate wheel trains 80.
Another novel feature used in combination with the hinge feature of my invention is a diagonally positioned abuttment bar 104 connected to the side of the scaffold structure as shown in FIGS. 1 and 2, which function to space the scaffold structure from the side of the building by abutting against the foundation 106 of the building. The lower end of the scaffold structure 12 is provided with a substantial clearance between the end thereof and the ground so that the debris and the roughness of the terrain will not interfere with the travel of the scaffold. As viewed in FIGS. 1 and 2, I provide sleeve clamp means 108 and 110 on scaffold pole members 14 and 16 to support abuttment bar 104 in a diagonal position. I further provide an end of the abuttment bar with, for example, rack teeth 112 which engages gear train 114 mounted on sleeve bar 116 on which bar 104 is supported. Gear train 114 is adapted to be manually driven by a crank handle to adjustably extend abuttment bar 104 whereby hanging scaffold apparatus 10 may be adjusted to a vertical position relative to the building side.
The scaffold apparatus 10 of my invention is provided with wheel train device 80 to which it is hingedly connected. The wheel train 80 is fitted to ride on track device 18 in the manner illustrated and described. The scaffold structure 12 is positioned vertical and parallel relative to the building wall by adjusting the extension of abuttment bar 104. The novel hinge connection between the cantilever beam structure 54 and wheel device 80 relieves the track device 18 of any torsional strain caused by the weight of the scaffold apparatus acting at a moment arm measured from its support which are tracks 20 and 22, and places the load on horizontal and vertical component forces. The horizontal force being through the abuttment bar 104 acting against building foundation 106, and the vertical force through bottom track wheels 66 on lower rail 22. When it is desired to travel the scaffold to a new position, a workman descends from the scaffold and pivots the scaffold on the hinge connection so that abuttment pole 104 clears building foundation 106 and walks the scaffold apparatus of my invention 10 to a new position and allows the scaffold apparatus to pivot toward the building until abuttment bar 104 abutts against building foundation 106.
This unique hinge connection between plate 90 of wheel train 80 and cantilever beam structure 54 allows a heavy scaffold structure 12 acting at a moment arm from its support to be supportable on a track device 18 relieved of a twisting strain. This eliminates the need for a heavily reinforced structure for the track frame and further allows for a light weight and simple track structure which may be manually lifted and constructed on the rafter frame of the building.