US2718378A

US2718378A - Material lift assembly for scaffold

Info

Publication number: US2718378A
Application number: US253718A
Authority: US
Inventors: Clifford L Lutton
Original assignee: Individual
Current assignee: Individual
Priority date: 1951-10-29
Filing date: 1951-10-29
Publication date: 1955-09-20
Anticipated expiration: 1972-09-20

Description

Sept. 20, 1955 c. L. LUTTON MATERIAL LIFT ASSEMBLY FOR SCAFFOLD Filed Oct. 29, 1951 mv m wv n m M mm J 3 m m m 4 mm Mm V. .& Wm I E E R .m M I mm 7 l y \Q Q NQQNQ a W Y E 8 a a m. .Q mm vmwk E Q N% 9Q Qh mm .vQ mm m9 o2 mm mm x M Q rPmw N 8 QQ 5 W w: a mm at an 9k mm mm N7 v 2,718,378 MATERIAL LrFT ASSEMBLY FOR SCAFFOLD I Clifford-L. Lutton, Washington, D. C.

Application October 29, 19151, Serial No. 253,718 1 (Cris i-1 90 This invention relates to-a material lift assembly and particularly to su h an assembly adapted to be mounted on the top of temporary scaffolding for lifting material onto the Scaffolding. f

This application is a'continuation-in-part of application Serial No. 253,7l 9, filed October 29, 1951, now Patent No. 2,673,711;

In 'the'eonstruction' and maintenance of buildings, it is frequently desirable to have workmen operate at various heights on-the wall or other portions of the building. It has'heretofore been customary to provide temporary scalfolding structures to support workmen in such positions. 'A sectionali'zed scaffolding support has been cons'tructed which-will allow the workmen to economically construct scaffolding of any desired height or to reach any/desired portion of a building. It is frequently desirableto elevate building'materials, tools or other mater'ial to theworkrnenon these scaffolds. Heretofore, such material has usually been lifted to the platform by means of ropes operated by the individual workmen on a platform. I

' Ithas "long beenrecognized-as desirable, and many attempts have been made to produce lift devices operated from power sources'onthe ground for lifting material onto temporary scaffolding.

The present invention provides a lift assembly in which laterally extending arms are-securely mounted on each or thebpri'ght standards ofthe seetionalized scaffolding and a sheave is mounted at-theend of each of the arms so that a ru'nning line may be run through the sheaves and; attached to alift-in the form-of a power driven winch on' the ground adjacent-to thescaffolding. 'Load' engaging pulleys are mounted on the running line between each of the sheaves and retriever line is attached to each of the pulleys and dropped to the ground so that a workman on the ground may selectively pull any of the pulleys down to the ground and attach a load, after which the winch will tension the running line and elevate the load to the workmen on the top of the scaffold.

It is accordingly an object of this invention to provide an improved lift assembly for attachment to a scaffolding.

It is another object of this invention to provide an improved lift for scaffolding.

It is a further object of this invention to provide the means for attaching a lift to the top of a scaffolding.

It is a further object of this invention to provide a means for rigidly spacing the sheaves of a running line lift assembly.

Other objects and many of the attendant advantages of this invention will be apparent from the following detailed description taken in conjunction with the accompanying drawing, in which:

Figure l is a top plan of a lift applied to a scaffold;

Figure 2 is a plan view of a stabilizing brace for the lift;

Figure 3 is an end view of the scaffolding showing the attachment of the lift thereto;

2,718,378 Patented Sept. 20, 1955 Figure 4 is an enlarged exploded perspective view'of the brace and attachment member for a lift.

In the exemplary embodiment accordingto the draw ings, a scaffold indicated generally at 10, has attached thereto the improved lift assembly indicated generally at 12.

A satisfactory scaffold can be constructed from a plurality of preassembled, individual sections 14. Asbest shown in Figure 3, thesesections'14 each comprise a pair of vertically extending

standards

16 and 18 which are rigidly attached to each other by

cross members

20 and 22. The standard'member's 16 and 18 are preferably of a tubular construction, the top end thereof having tele scoping pins 24 and 26 secured therein for securing the sections 14 together. A scaffold of any height maybe assembled by telescoping the standards 16 and 1'8 o'nt o the pins 24 and 26 of a lower section. Pairs of standards produced by this telescoping arrangement are laterally separated by any desired distance so that

load members

28 and 30 may be mounted on the

cross members

22 or 20 or intermediate cross pieces 32. Obviously, any desired number of cross pieces 32 may be utilized, and they may extend completely across the members 16 and 18101- they may extend partially across and be supported in the middle by means of' a vertically extending member 34.. The longitudinal sections 14 are longitudinally separated from each other at any desired distance and arei rigidly held in this spaced relation by means of cross braces 36 detachably connected between the adjacent sections 14. This construction provides a scatfoldhaving a plurality of longitudinally rigidly spaced vertically extending standards 18, to which is rigidly attached

cross members

20 and 22 which extend transversely of the line of standards 18. I

The lower portion of the hoist includes a beam 40. rigidly attached to the base of one of the standards 18 by any suitable means such as U-bolts 42. The beam 40 may conveniently be constructed of an'angle iron having a flat side 44 secured against the.

standards

16 and 18 and a laterally extending top flange 46 having anopening' 48 therein, in which is mounted a screw fastener, such as a bolt 50, on which is journaled a frame 52 of a pulley 53 having a sheave 54. The frame 52 is extended laterally alongside of the sheave 54 to provide a line guide so that a rope or line mounted on the sheave 54 will be prevented from jumping off the track of the sheave.

The top portion of the lift 12 includes a plurality of sheave supporting members indicated generally at 56, the sheave supporting member being supported on each of the standards 18 adjacent the top thereof.

As best seen in Figure 4 each of the sheave supports 56 comprises a laterally extending arm 58 preferably of tubular construction and having connected thereto adjacent the outer end thereof brace member 60. The arm 58 has a cross-head 62 having a concaved portion 64 for contact with the standard 18. The head 62 provides one portion of a clamp member for embracing the standard 18 and the other portions constitutes a keeper plate 66 having openings 68 therein for engaging screw fasteners such as the bolts 70 and 72 which are preferably rigidly connected in the heads 62, but obviously may be loose bolts if so desired. The openings 68 fit over the screw fasteners 70 and 72 and are rigidly attached thereto by means of the nuts 74 the keeper plate 66 having an upstanding portion 76 and in which is included a longitudinally extending slot 78 for engagement with a cross member 22. Brace member 60 is also provided with a cross-head 80 of similar construction to cross-head 62 and which is arranged in spaced substantially parallel relation to the cross-head 62. A keeper 82 is provided for cross-head 80 and screw members 84 engage the keeper plate 83 and are secured thereto by means of nuts 86. Securing the member 56 to the top of the standard 18 the heads 62 and 80 are placed in contact with the sides of the standard 18 and the keeper plates 66 and 82 secured in position with the slots 78 of the keeper plate 66 being extended over and embracing one of the cross members 22. Clamping engagement of the heads 62 and 80 against the sides of the standard maintain member 56 against angular movementtherewith and the engagement of the hook portion 76 over the cross member 22 prevents longitudinal motion of the member 76 along the standard 18.

I An axle shaft 90 extends into the end of the arm 58 and has rotatably mounted thereon a sheave 92. A line guide 94 embraces the sheave 92 and is rigidly secured by any suitable manner to the axle shaft 90.

Each of the standards 18 is provided with one of the sheave supports 56 and a running line 100 is Wound on a drum 102 of a winch 104 having a driving motor 106. The running line 100 passes through the sheave 54 of the pulley 53 and extends upwardly to the sheave 92 mounted directly above the pulley 53 thence the line runs through each of the sheaves 92 upon each of the standards 18 and at the end of the line of standards 18 extends downwardly to be connected to the counter-weight 110. Load engaging pulleys 112 are mounted on the line 100 between each of the sheaves 92. A suitable retriever line (not shown) is attached to each of the pulleys 112 so that any of the pulleys 112 may be selectively pulled to the ground for the attachment of a load thereto.

The weight 110 is preferably just in excess of the weight of a maximum load which is intended to raise by means of the lift. Counter-weight 110 is provided as a safety measure so that if the drum 102 should over-run the tensioning of the line 100 produced thereby will lift the weight 110 and prevent excessive stress being applied to the scaflfold and the lift assembly.

, Since the winch 104 is disposed on the ground adjacent to the scaffolding an excessive load or other strain might cause the winch to pull the scaffolding or to shift the location of the winch. To prevent this

braces

132 and 134 have been provided between the front corners of the winch 104 and suitable ones of the standards 18. Braces 132 and 134 prevent the movement of the winch and the scaffold so that there is no danger to either the scaffold or the winch because of shifting by an excessive strain on the running line 100.

To construct and operate the lift according to the present invention the sheave supporting members 56 are placed on each of the spaced apart standards 18. The running line 100 is assembled through the sheaves 92.

4 Obviously the rope or line may be assembled in the sheaves prior to their fastening on the standards 18 or afterwards as being desired. In order to prevent the supports 56 from being drawn to each other by the weight of the load supported between the sheaves by the pulleys 112 it is desirable to provide brace members 140, each of which comprise a pair of

rods

142 and 144 and are secured together adjacent the central portion thereof by means of a fastening means such as a rivet 146. The ends of the

rods

142 and 144 are provided with eyes 148 and the arms 58 are provided with a pair of

openings

150 and 152. Preferable fasteners such as the bolts 154 are utilized to firmly but detachably connect the cross braces from the adjacent pairs of sheave supports 56. In this manner the entire structure of the top of the lift is provided as a rigid substantially unitary structure so that the running line may carry a load between any of the pairs of sheaves 92 without causing displacement or sagging of the scaffold or the lift mechanism.

While a specific embodiment of the invention has been shown and described according to the best present understanding thereof, it will be apparent that many changes and modifications, can be made therein, without departing from the true spirit of the invention.

Having described the invention, what is claimed as new In a material lift assembly adapted to be mounted on a scaffold, a sheave support comprising a tubular arm, a brace member rigidly attached to said arm in angular relation, said brace member, terminating in spaced perpendicular relation to an end of said arm, a transverse head secured to said end of said arm, spaced fastening means in said head, a keeper plate detachably mounted on said fastening means, ,a head on said brace member parallel to said first mentioned transverse head, a keeper member detachably secured to said second head, an axle rod secured in the open end of said arm, a line guard mounted on said axle, and a sheave journaled on said axle within said guard, said keeper plate having a transversely disposed slot.

References Cited in the file of this patent UNITED STATES PATENTS Tuttle May 25, 1943