US2840423A

US2840423A - Knock-down scaffold

Info

Publication number: US2840423A
Application number: US589504A
Authority: US
Inventors: Lloyd E Dempsey
Original assignee: Individual
Current assignee: Individual
Priority date: 1956-06-05
Filing date: 1956-06-05
Publication date: 1958-06-24
Anticipated expiration: 1975-06-24

Description

June 24, 1958 E. DEMPSEY 2,840,423

KNOCK-DOWN SCAFFOLD Filed June 5, 1956 INVENTOR.

L L. 47 r0 5 DEM/05E) BY ATTORNEYS Unite States Patent D KNOCK-DOWN SCAFFOLD Lloyd E. Dempsey, Portland, Greg. Application JuneS, 1956, Serial No. 589,504

1 Claim. (Cl. 304-2) This invention relates to knock-down scaffolds, and is more particularly concerned with the type of scaffold used in the erecting, dismantling, repairing, or painting of buildings.

The principal object ,of the present invention is to provide scaffold end frames which are simple in structure and economical to manufacture.

Additional objects are to provide scaffold end frames which make for a rigid and sturdy scaffold assembly, which facilitate quick erection and dismantling of the scaffold, and which may be connected and disconnected from other scaffold structure without the use of tools.

A further object is to provide a knock-down scaffold utilizing a minimum of removable fastening elements for detachably holding the parts together.

More specific objects of the invention are to provide a'scaffold utilizing end frames having novel socketed connecting means for securing together component parts of the end frames and for connecting together in vertically stacked relation a pair of the end frames, and to provide a novel anchor bracket for connecting the end "frames .with longitudinal brace members.

According to the present invention, 0116 section .of a scaffold comprises a pair of end frames interconnected by longitudinal braces to form a rigid upright structime ;Each of the end frames is preferably principally constructed of Wood pieces to reduce the cost of construction and yet form a rigid unitary scaffold part. The end frames comprise horizontal frame members and angular braces secured toa .pair of vertical legs which carry at their .upper ends socketed connectors adapted toconnect togethera pair of .the end frames in vertical stacked relation and adapted also to form an integral connection for one of said horizontal frame members between the two vertical legs. Longitudinal rigidity of the individual scaffold sections is accomplished by longitudinal braces detachably connected to the vertical legs of the end frames by improved anchor bracket means.

The invention will be better understood and additional objects and advantages will become apparent from the following description taken in connection with the accompanying drawings which illustrate a preferred form of the invention. It is to be understood, however, that the invention may take other forms, and that all such modifications and variations within the scope of the appended claim, which will occur to persons skilled in the art, are included in the invention.

In the drawings:

Figure 1 is a fragmentary perspective view of scaffold sections showing, in particular, the construction of the end frames thereof;

Figure 2 is an edge view of the socketed connector for interconnecting two end frames in vertical stacked relation;

Figure 3 is a side elevational view of the connector; Figure 4 is an edge view of the, anchor bracket for connecting the end frame with the longitudinal cross braces; and

Patented June 24, 1 958 Figure 5 is a side elevation-a1 view ofthe anchor bracket.

Referring first to Figure 1, end frames 10 are shown which, together with other identical frames, formscatfold sections. The sections may be disposed in superimposed relation, as shown, as well as longitudinal relation to provide suitable supports of desired height and length for platforms upon which workmen can be supported above the ground.

The two end frames 10in a section are interconnected into a rigid scaffold part by means of longitudinally disposed braces 12, preferably disposed in pairs on each side and crossed for imparting longitudinal structural rigidity to the scaffold section. The cross braces 12 preferably comprise metallic tubular members and'have apertured flattened end portions '13.

Each of the end frames 10 comprises a pair of vertical 'legs 14 interconnected transversely by an upper horizontal frame member 17 and a lower horizontal frame member 18, these frame members being adapted to support planking to form a working platform. The legs 14 and the transverse frame members '17. and '18 are preferably constructed of wood of a type having sufiicient rigidity for the intended purpose, such as Douglas fir. 'Such construction makes for economy ofmanufacture and yet provides a structure-having sufiicient rigidity for all purposes to which this type of scaffold is to be put. Angular stiffening members or braces .20 are secured between the legs '14 and the horizontal frame members 17 to stiffen transversely the end frames. I

Mounted at the upper end of the legs 14 are connectors 25 with U-shaped

socket portions

26 and 27 having their open ends disposed in opposite directions. The socket portion '27, which is ofgreater width than socket portion 26, receives the upper end of a leg 141and one end of the frame member 17, and these frame parts are integrallysecured in the connector by cross bolts 28; It is thereby apparent thatthe vertical legs 14 are securely attached to the horizontal frame member '17 by the socket connector 25 for forming a rigid structure. A web plate 30 is secured to the side edge of the socket portion adjacent the bottom to reinforce the Walls of the socket and also to provide a stop or guide plate for assisting in the assembly of the parts when the frames are being manufactured.

The other socket portion 26 has its opening disposed upwardly for receiving the bottom end of a leg, 14,of

the next upperv end frame 10. To temporarily interconnect the two vertically disposed end frame's S'Qlllaf in assembled scaffold relation there will be no relative vertical movement therebetween, a pin 32 is mounted in suitable apertures in the walls of the socket portion 26. This pin has a bent head portion 33 and the oppo site end is provided with a toggle link 34 which is pivoted on a pin 35 radially mounted in the pin 32 and which, when axially aligned with the pin 32, will permit the pin 32 to be removed from the socket walls by slidable movement thereof relative to the socket in the direction of the head 33. When the link 34 is pivoted to a position at right angles to the axis of the pin 32, the pin is then locked in place to form a positive connection between two vertically disposed end frames of the scaffold. The side walls of the socket portion 26 adjacent the open end thereof are reinforced by transverse web plates 37. The bottom end of legs 14 are suitably apertured at 38 for receiving the pins 32 of a connec tor on another scaffold section.

Figures 4 and 5 show in detail a U-shaped anchor bracket 39 mounted on the inwardly facing edges of the legs 14 by means of bolts 40. Forming an integral part of the bracket 39 is a threaded stud 41 projecting from the end' wall of the U-shaped bracket. This stud has a head 42 and a has a wing nut 43 threadedly mounted thereon. An anchor pin 44 of a shorter length than the stud 41 is disposed below the stud in parallel relationship therewith and is adapted to receive the apertured end 13 of-the braces 12 for assembling the scaffold section. A clamp plate 45 has apair of

apertures

46 and 47 disposed in predetermined spaced relation so as to receive, respectively, the stud 41 and anchor pin 44,

and these apertures are slightlylarger than the stud and pin so that the plate 45 is freely slidable on the parts. As the pin 44 is somewhat shorter than the stud 41, the wing nut 43 canbe threaded outwardly to a position beyond the end of the pin 44 whereby the plate 45 can be moved over the end of the pin to disengage itself therefrom. The plate can thereby be rotated away from thepin and a brace 12 then placed on the pin or removed therefrom. In the assembled relation of a platform section, the braces 12 are mounted on the pins 44 and are clamped firmly between the bracket and the 'plate 45 by the wing, nut. This structure provides a good connection between the parts described with no resulting damage to the threads of the stud 41. 7

To assemble a scaffold section utilizing the present structure, the end frames 10 are connected together by the longitudinal braces 12 by anchoring the braces 12 on the ,pins 44 of brackets 39. The scalfold rnay be extended vertically by superimposing another similar section on the already assembled section, the bottom portion of legs 14 of the next upper section being placed in the socket portions 26 and thepin 32 placed therein in engagement with the aperture 38 in theleg. When it is desired to place the scaffold sections in end to end relationship, such sections are held together by connecting a pair. of the braces 12 from adjoining sections on the same pin 44 The structure thus provided makes for a scaffold section which is economical to rnanfacture and which is readily and conveniently erected or dismantled and which is structurally rigid for, all purposes to which this type of platform is used. A sturdy structure is formed by utilizing conventional board: sizes, such as 2 x 4s for the legs 14 and 1 x 6s for the

horizontal frame members

17 and 18, although, of course, other board sizes may beused. Li

The. only fastening elements which are capable of being accidentally misplaced are the pins 32, and this feature will prevent the loss of many hours consumed in looking for lost fastening elements and obviate the expense of obtaining new ones. The wing nuts 43 and the plates 45 are not removable from the studs 41 and thereby cannot be misplaced.

Having now described my invention and in what manmlthe same may be used, what I claim as newand desire to protect by Letters Patent is:

In a scaffold, a rectangular unitary end frame comprising a pair of legs, each leg being a single wooden member of rectangular cross section, a lower horizontal cross member connected at its ends to said legs at a distance from the lower ends of the legs, an upper wooden horizontal cross member of rectangular cross section connected at its ends to the upper ends of said legs, the top edge of said upper cross member being flush with the top ends of said legs and the ends of said upper cross member being flush with the outer edges of said legs both of said cross members being rigidly and permanently connected with said legs; a double socket connector on the upper end of each leg comprising a horizontal seat plateoverlying the top end of the leg and the top edge of said upper cross member, a pair of parallel depending side plates on opposite lateral sides of said seat plate extending downward over the vertical faces of said leg and cross member, a pair of upstanding side plates on said seat plate parallel with said depending side plates and spaced apart a distance equal to the thickness of the leg to receive the lower end of another end frame leg, web plates interconnecting the vertical edges of said upstanding side plates to form a socket for said other end frame leg, all of said plates being integrally connected together in a rigid unit; a plurality of bolts rigidly and permanently connecting said depending plates to said leg and upper cross member, and quick releasable means for detachably connecting said upstanding plates to the lower end of said another end frame leg.

References Cited in the file of this patent UNITED STATES PATENTS 191,953 Gilchriest June 12, 1877 450,127 Wrigley Apr. 7, 1891 534,274 Massau Feb. 19, 1895 704,884 Lally July 15, 1902 1,437,089 Brandt Nov. 28, 1922 2,323,195 Bouchillon June 29, 1943 2,413,569 Isakson Dec. 31, 1946 2,479,962 Paulson Aug. 23, 1949 2,481,885 Simpson Sept. 13, 1949 2,576,400 Howie Nov. 27, 1951 2,626,189 Brown Jan. 20, 1953 FOREIGN PATENTS 9,899 Great Britain Apr. 23, 1910 28,045 Germany July 26, 1884 134,296 Sweden Ian. 22, 1952 1,040,056 France Oct. 13, 1953