US2717801A

US2717801A - Lifting apparatus for construction materials

Info

Publication number: US2717801A
Application number: US306622A
Authority: US
Inventors: William P Neil
Original assignee: Individual
Current assignee: Individual
Priority date: 1952-08-27
Filing date: 1952-08-27
Publication date: 1955-09-13
Anticipated expiration: 1972-09-13

Description

"v -ilk- Sept. 13, 1955 w. P. NEIL 2,717,801

LIFTING APPARATUS FOR CONST Filed Aug. 27, 1952 RUCTION MATERIALS 2 Sheets-Sheet l J \J 3x INVENTOR:

W/LL/AM P NE/L. BY

Sept. 13, 1955 w. P. NEIL 2,717,801

LIFTING APPARATUS FOR CONSTRUCTION MATERIALS Filed Aug. 27, 1952 2 Sheets-Sheet 2 50 INVENTOR: W/LL/AM F. NE/L.

United States Patent OfiFice LIFTING APPARATUS FOR CONSTRUCTIQN MATERIALS William I. Neil, Pasadena, Caiif. Application August 27, 1952, Serial No. 366,622 8 Claims. (Cl. 294-67) in rows, such columns serving as supports for the ends verseiy of the planes of adjacent lines of the roof trusses, the ends of each joist being suitably secured to opposite, parallel trusses to extend therebetween, or to trusses and a parallel wall. In order to place a heavy joist in position, it is common practice to employ a boom-type crane, the lifting cable of which is suitably connected, as by the use of a sling, to the joist, the boom then his balance or footing and fall when attempting to guide such a long, heavy beam into place. Such loss of balance may also occur when a workman walks out along my knowledge.

It is therefore an object of this invention to obviate the inefiiciencies and hazardous conditions encountered 2,717,801 Patented Sept. 13, 1955 being loaded with the joists when positioned on the floor beneath the roof trusses.

Another object is to provide an apparatus of the charter referred to in which the carrier is provided with indicated in which the carrier frame is provided with a plurality of transversely extending platforms or shelves arranged in stepped relation, each shelf being adapted to support one of the roof joists. A related object is to of each step-like shelf retainer mounted thereon, may be lifted bodily to the approximate level of the trusses or rafters between which the joists Since the extension is disposed at the trusses of the roof structure.

The procedure followed in so positioning the joists involves first lifting the carrier above the level of the rafters and positioning the carrier so that the lowermost joist thereon extends at right-angles to the parallel trusse time involved m constructing the building roof is minim zed and this results in a greatly decreased over-all building cost.

joists into place, the'danger of the workmen losing their balance s also minimized. In addition, since the lifting tioned joist to disconnect the cable therefrom is wholly avoided and this also makes for greater safety.

A further object of the invention is to provide a carrier of the type specified which embodies a framework constructed entirely from structural shapes welded together, the carrier also having brake-like feet at one end which provide fulcrums about which the carrier may be tilted upwardly or pivoted downwardly to avoid rolling of the carrier during such movement.

A still further object of the invention is to provide a lifting apparatus, of the character referred to, which is extremely simple in construction and economical to manufacture, one which is comparatively light in weight and easily maneuvered, and one which is highly practical and efiicient in performing its intended function.

Further objects will become apparent from the lowing description and from the drawings, tended for the purpose of illustration only, and in which:

Fig. l is a perspective view of a portion of a roof structure, showing the present lifting apparatus applied to use in setting a plurality of roof joists in position between parallel roof trusses;

Fig. 2 is a perspective view of the mobile and liftable carrier for supporting the plurality of roof joists;

Fig. 3 is a plan view of the carrier; and

Fig. 4 is a side elevational view of the carrier which is shown in an inclined position assumed when it is being lifted from the floor or lowered onto the same; and

Fig. 5 is a small scale sectional view, taken on line 5-5 of Fig. 1.

Referring first to lifting apparatus 5 is ing roof joists 6 into position where they may be mounted between the upper members 7 of Fink-type roof trusses 8 or to horizontal roof members 9 connecting the adjacent ends of said members of the aligned trusses. It is to be understood that the lifting and positioning apparatus of the instant invention is not limited to use in connection with a roof structure of the specific type shown but rather is adaptable for use in lifting and positioning roof joists between other forms of roof trusses and rafters. The roof structure shown, by way of example, has been successfully employed in connection with large industrial buildings of the so-called precast, tilt-up panel types, such a structure being disclosed in my pending application, Serial No. 286,791, filed May 8, 1952, and titled Concrete Buildings and Method of Producing Same, to which reference is made for a more detailed description of such a building. In general, a building of this type consists of a concrete floor, concrete footings bordering the floor and a series of concrete wall columns and panels precast upon the floor and tilted up into position upon the footings to form the walls of the building, the wall columns being formed either integrally with the panels or cast as separate elements to which the panels are suitably joined to provide the wall. In addition to the wall columns, other interior columns, such as those shown at 11, are set up upon footings and arranged in alignment across the building. The roof trusses 8 are set up in parallel rows With their ends resting upon hearing portions 12 of the inner columns 11 and upon bearing portions of the outer wall columns, shown in the pending application referred to above. In mounting the roof joists 6 between the trusses 8, the latter are provided with double U-shaped straps or stirrups 15 for receiving the ends of the joists, said ends being lowered into the stirrups and thereafter secured to the members 7 and 9 by the usual toe nails.

The roof joists are, according to the conventional procedure, lifted individually from the floor upon which they are stacked, by means of a mobile crane unit having a movable boom and a lifting cable detachably connectible to each joist by means of a sling. Each roof joist is lifted to a position above the parallel trusses, turned to extend normal to the trusses and then lowered into position between the trusses, workmen stationed on the trusses guiding the ends of the joist into the U-shaped stirrups.

folwhich are in- Fig. 1 of the drawings, the present designed particularly for use in liftr mount the joists 6 workman then disconnects the sling from the joist, after which the lifting cable is lowered to receive another joist. As previously pointed out, such a conventional procedure is a slow, laborious and expensive one and the over-all cost of erecting the building, based on the man-hours involved, thus is materially increased. This is an extremely important consideration where the otherwise inexpensive, precast, tilt-up method of construction is involved. The instant invention is concerned with an apparatus designed particularly for expediting the erection of such roof structures by permitting the simultaneous lifting of a plurality of the roof joists to be installed between the trusses by simply lowering the joists individually and successively into position for attachment to the trusses. In accordance with my invention, this concept involves the use of a frame-like holder or carrier 20, to be next described.

Referring particularly to Fig. 2 of the drawings, the carrier 29 is in the form of a rectangular frame or chassis having

end members

21 and 22 and

side members

23 and 24, all of which are preferably made tions, such as strips of angle-irons. Attached to the underside of the frame, at the corners thereof, are caster units 25 having swivel caster wheels 26. The carrier frame also has

upright corner posts

28 and 29, and a lateral extension or arm 30 at its forward end consisting of a pair of convergent bars 31. The outer end of the extension 30 carries a plate 32 provided with a relatively large hole or eye 33 through which the hook of a lifting cable may engage.

The sides of the mobile carrier 20 are composed of upright angle-

iron bars

36, 37 and 38, and longitudinally extending angle-

iron bars

39, 40, 41 and 42 extending between the uprights and the

corner posts

28, 29, these several components preferably being welded together, and to the frame 2124, to provide a strong, rigid unitary structure. Cross-struts or

ties

43 and 44, extending transversely between the sides of the carrier further strengthen the structure.

It is to be noted that the longitudinal side bars 39 to 42 at each side of the carrier 20 are arranged at progressively higher levels, in other words in upwardly stepped relation from the end of the carrier at which the lifting arm 30 is located, these horizontal bars being, in effect, the treads of the steps while the

uprights

36, 37 and 38 and

corner posts

28, 29 constitute the risers. As will presently appear, the horizontal treads 39 to 42 provide supports for the roof joists 6 when the carrier is at rest upon the floor while the risers 36 to 38 and the rear corner posts 29 form such supports when the carrier is lifted with its forward end 30 uppermost. In order to retain the roof joists 6 on the carrier 20, each riser is provided with a lateral finger or retainer bar 48, said bars overlying the rearward portions of the horizontal treads and defining therewith slots 49 in which the longitudinal edges of the joists 6 are disposed when mounted on the carrier.

The carrier 20 is further provided with blocks 50 at its rearward end for the purpose to be later explained. The rearward corner posts 29 are provided with holes through which guiding ropes 52 may be detachably looped.

Assuming that the building construction has progressed to the stage Where the roof trusses 8 have been erected to extend between the columns 11 and it is now necessary to between the trusses, such placing of the joists is carried out in the manner to be next explained. With the carrier 20 at rest upon the floor of the building, roof joists 6 are placed on the carrier as indicated by the broken lines in Fig. 2. To so load the carrier 20, a joist 6a is taken from a stack of the joists and placed upon the uppermost supports 42 and slid rearwardly to cause its longitudinal edge to be located in the slot 49. Other joists 6b, 6c, and 6d are similarly and successively placed on the

supports

41, 40, and 39 with their longitudinal edges disposed beneath the retainer bars 48. When so mounted on the carrier 20, the several joists 6a to 6d are arranged in. stepped relation, both horizontally and vertically, as

shown. The loaded-carrier 20 is then wheeled along the floor to assume of trusses 8.

A mobile crane is between the lifting cable Th a position beneath and between two rows so stationed as to locate its boom parallel trusses 8-, said crane boom having a 55 provided with a book 56 at its end. e hook is passed through the eye 33 of the carrier joists 6a to 6d are supported by the corner posts 29, and are retained on the carrier by reason of their being held in the slots 49. During the upward tilting movement of the carr1er'20, the-latterpivots on the blocks and upsetting placement of the joists.

The carrier 20, together with the joists mounted thereon, is next lifted by the crane to a position posite stirrups 15. 6a is quickly positioned to form part of the ture.

rality of the joists in position For example, by simultaneously lifting four of the joists over-all cost of the In accordance building structure. with the provisions of the patent have it understood out by further modified means.

I claim as my invention:

iftable carrier for use in 1. A 1 between parallel roof elements,

rier releasing 2. I A liftable carrier for use in placing joists to extend between parallel roof elements, comprising: a frame tiltable on one end from a horizontal loading position to a vertical lifting position; caster wheel on said 3. A liftable carrier for use in placing joists to extend between parallel roof elements, comprising: a rectangular of the joists when the frame is in its horizontal loading position and operative to prevent lateral displacement of the joists when the frame is in its vertical lifting position;

and an extension integral with the frame and providing a lifting means at the opposite end of the frame by which the carrier can be tilted upwardly and lifted bodily by a crane to a position between said parallel roof elements, said carrier being movable successively downwardly and laterally by the crane so as to deposit the joists carried thereby singly and successively along and between the roof elements, said downward movement of the carrier releasing the joists from said slots.

4. A liftable carrier for use in placing joists to extend between parallel roof elements, comprising: a rectangular frame tiltable on one end from a horizontal loading position to a vertical lifting position; caster wheels on said frame by which the carrier may be moved along a floor; a plurality of support means at the sides of said frame, each adapted to support a joist placed thereon, said support means being arranged in stepped relation vertically and horizontally, the support means located adjacent said one end being of highest elevation; retainer means at the sides of the frame overlying each of said support means and defining, with said support means, transverselyspaced, horizontally extending slots for laterally receiving longitudinal edges of the joists when the frame is in its horizontal loading position and operative to prevent lateral displacement of the joists when the frame is in its vertical lifting position; and an extension integral with the frame and providing a lifting means at the opposite end of the frame by which the carrier can be tilt'ed upwardly and lifted bodily by a crane to a position between said parallel roof elements, said carrier being movable successively downwardly and laterally by the crane so as to deposit the joists carried thereby singly and successively along and between the roof elements, said downward movement of the carrier releasing the joists from said slots.

5. A liftable carrier for use in placing joists to extend between parallel roof elements, comprising: a relatively wide rectangular frame tiltable on one end from a horizontal loading position to a vertical lifting position; caster wheels at the corners of said frame by which the carrier may be moved along a floor; a plurality of longitudinally spaced uprights at the sides of said frame; horizontal bars connected between said uprights and providing horizontal supports upon which joists may be placed with a longitudinal edge of each joist disposed against a said upright; horizontal retainer fingers on said uprights each overlying a said horizontal bar, said fingers defining with said bars and said uprights horizontal recesses having their open ends disposed toward the opposite end of said frame to receive said longitudinal edges of the joists, said longitudinal edges being restable upon said uprights within said recesses when the carrier is tilted upwardly on said one end; and a rigid, integral lifting means at the said opposite end of the frame by which the carrier can be tilted upwardly and lifted bodily by a crane to a position between said parallel roof elements, said carrier being movable successively downwardly and laterally by the crane so as to deposit the joists carried thereby singly and successively along and between the roof elements, said downward movement of the carrier releasing the joists from said recesses.

6. A carrier as defined in claim 5 in which said frame, said uprights, said horizontal bars and said lifting means are structural shapes and provide a rigid, unitary structure, said carrier also including tie-rods extending between the sides of the carrier.

7. A carrier as defined in claim 5 including brake block means carried by said frame at its said opposite end and providing a fulcrum by which the carrier can be tilted on the floor.

8. A carrier as defined in claim 5, including block means carried by said frame at its said opposite end and providing a fulcrum by which the carrier can be tilted on the floor, and a pair of steering ropes detachably connected to the carrier at said opposite end thereof.

References Cited in the file of this patent UNITED STATES PATENTS