US3128842A

US3128842A - Attoknevs

Info

Publication number: US3128842A
Authority: US
Publication date: 1964-04-14
Anticipated expiration: 1981-04-14

Description

April 14, 1964 c. SATRUM 3,128,842

.COLLAPSIBLE ADJUSTABLE SCAFFOLD Filed July 9, 1962 INVENTOR CZARE'NCE S'ATEUM BY wbw PM Arrow/1949 United States Patent Office 3,128,842 ?atented Apr. 14, 1964 3,128,842 COLLAPSEBLE ADJUSTABLE SCAFFGLD tillarence Satrum, 224 W. 23th St, Minneapolis, Minn. Filed July 9, 19:12, Ser. No. 298,311 3 Claims. (iii. 182-149) This invention relates to scaffolds and more particularly to a readily adjustable scaffold.

An object of this invention is to provide a novel scaffold apparatus, of simple and inexpensive construction, having a longitudinally adjustable platform and having vertically adjustable foldable supporting legs thereby permitting the scaffold to be easily and quickly collapsed into a structure of small compass for ready portability.

Another object of this invention is to provide a novel and improved scaffold structure including a longitudinally adjustable platform having vertically adjustable folding legs, and winch means for adjusting each leg so that an operator positioned upon the platform may readily raise, lower and level the platform.

A further object of this invention is to provide a novel and improved scaffold of the class described wherein each of the legs are independently foldable and adjustable relative to each other so that one leg may be folded to a collapsed position to permit the platform to be supported at one end upon a selected step of a stairway while the other end of the scaffold is supported by the other leg, the latter being readily vertically adjustable to level the platform thereby enabling workers such as painters and the like to work efiiciently in heretofore difiicult places such as stairway areas.

These and other objects and advantages of this invention will more fully appear from the following description made in connection with the accompanying drawings wherein like character references refer to the same or similar parts throughout the various views, and in which:

FIG. 1 is a perspective view of the novel scaffold illustrated in an erect operative position;

FIG. 2 is a side elevational view of the scaffold with one leg illustrated in a folded collapsed position while the other leg is illustrated in an erect position and with one end of the scaffold platform being supported upon a step of a conventional stairway; and

FIG. 3 is a vertical sectional view taken approximately along line 33 of FIG. 2 and looking in the direction of the arrows.

Referring now to the drawings and more particularly to FIG. 1, it will be seen that one embodiment of this novel scaffold generally designated by the reference numeral is thereshown. All of the components of the scaffold it) are preferably constructed of a rigid, light weight, metallic material such as aluminum or the like although other types of material may be employed. The scaffold 11) includes a longitudinally extensible generally fiat platform 11 comprised of a pair of platform sections 12 telescopically interconnected together for longitudinal extensible and retractable movement relative to each other.

Each of these platform sections 12 is comprised of a plurality of elongated, longitudinally extending, support elements 13 arranged in spaced apart, side-by-side relation, as best seen in FIGS. 1 and 3. The respective ends of these elongate support elements 13 of each platform section are rigidly secured between and are affixed to upper and lower transversely extending support elements 14. The transversely extending support elements 13 are secured to the associated elongate support elements by any conventional securing means such as bolts or the like.

It will be noted that the elongate support elements of one platform section are arranged in staggered relation with respect to the elongate support elements of the other section and that the spacing between adjacent elongate support elements of one section is of a size to receive an elongate element of the other section therebetween.

Thus it will be seen that the transversely extending support elements 14 which are secured to the innermost ends of the elongate support elements of one section also serve as guides for the elongate support elements of the other section during axial extension and retraction of the platform section.

Opposite ends of the platform 11 are supported by extensible and retractable leg structures and which are designated generally by the reference numeral 15. Each of the leg structures are of similar and each is preferably formed of a light weight metallic material such as aluminum or the like. Each of these leg structures includes an upper leg section 16 and a lower leg section 17 telescopically interconnected for vertical extension and retraction.

Each of the uppen leg sections 16 are comprised of a plurality of elongate, spaced apart, upstanding structural leg elements 18. The respective upper and lower ends of these upstanding structural legs 18 are rigidly secured to transverse structural leg elements 19. It will be noted that the transverse leg elements 19 are secured to opposite sides of the vertically disposed leg elements 18 in rigid affixed relation therewith. It will also be noted that the vertically extending structural leg elements 18 are arranged in side-by-side pairs so as to define a pair of vertical slides for cooperative engaging relation with the lower leg section 17.

The lower leg section 17 of each leg structure is comprised of a pair of vertically inclined structural leg elements 20 and a pair of vertically disposed structural leg elements 21. The respective upper and lower end portions of the upstanding structural leg elements 2% and 21 of each lower leg section are rigidly secured to transversely extending structural leg elements 22, as best seen in FIG. 1. It will also be noted that these transverse structural leg elements 22 are rigidly affixed to opposite sides of the upstanding

structural leg elements

20 and 21 by conventional securing means such as bolts and the like. It will also be noted that the lower leg section 17 of each leg structure is substantially wider than its associated upper leg section 16, the latter having a width corresponding generally to the width of the platform 11.

Each of the vertical structural leg elements 21 of each lower section of the leg 17 is of a Width to he received between adjacent of the upstanding structural leg elements 18 of its associated upper leg section 16. Thus it will be seen that each of the vertical structural elements 21 are slidably' engaged by a pair of adjacent upstanding structural elements 18 to thereby permit the upper leg section 16 of each leg structure to be slidably extended wd retracted relative to its associated lower leg section 17.

Referring now to FIG. 2, it will be seen that each of the upper leg sections 17 is hingedly connected to the outer end of one of the platform sections by means of hinges 23. The hinges for each leg structure are secured to the inner surface of the inner upper transverse structural leg element 19 are also secured to the underside of the outer transversely extending support element 14 of one of the platform sections 12. This hinge connection permits the legs to be readily folded to a collapsed position as illustrated by one of the leg structures in FIG. 2, and also permits the leg structures to be readily moved to an erect position.

Foldable brace elements are provided which serve to brace the platform 11 and also for maintaining the leg structures 15 in erect position. To this end, it will be noted that each leg structure 15 is provided with a pair of brace members 24, each of which is comprised of a pair of elongate brace sections 25 rigidly secured together by a hinge 26. One brace section of each brace member 24 is hingedly secured by means of a hinge 27 to the lowermost, inner, transverse structural leg element 19 of one of the upper leg sections 16. The end of the other brace section of each brace member 24 is hingedly connected to the lowermost, transverse, support element 14 of one of the platform sections 12 by means of a hinge 28.

Thus it will be seen that the brace members 24 are movable between their extended diagonal positions as illustrated in FIG. 1 to a folded or collapsed position as illustrated on the left side of FIG. 2. It will also be noted that each of the brace members 24- is provided with means for locking the brace member in the extended operative position. This lock means includes a lock element 29 pivotally mounted adjacent one end portion of one of the brace sections and the lock pin 30 secured to the adjacent end of the associated brace section. This releasable latch means permits the brace section to be releasably locked in end-to-end, diagonally extending relation.

Means are also provided for vertically extending and retracting the upper leg section of each leg structure relative to its associated lower leg section. This means includes a winch mechanism for each leg structure and each of these winch mechanisms includes :an elongate revolvable winding shaft revolvably mounted in transversely extending relation on the transverse structural leg element 19 of its associated upper leg section. This revolvable winding shaft of each Winch mechanism is provided with an offset crank handle 32 rigidly afiixed to the shaft for movement therewith. It is pointed out that the winding shaft 31 is jo'urnalled in suitable bearings to permit the shaft to be revolved about it longitudinal axis. One end of the winding shaft 31 is provided with a suitable ratchet and pawl lock mechanism 33 which is suitably enclosed within a housing. The ratchet and pawl unit of each winch mechanism is provided with a small release element 34 for releasing the pawl from locked relation with respect to the associated ratchet wheel.

Secured to the winding shaft 31 of each winch mechanism is an elongate flexible element or rope 35 which is windable thereon. -It 'will be noted that the other end portion of the flexible rope 35 is secured to the upper portion of the associated lower leg section 17 at a centrally located point with respect to the width thereof. A suitable guide member or pulley 36 is mounted upon the lower end portion of the upper leg section and it will be seen that the flexible rope 32 is trained around this pulley. It will also be noted that even when the upper leg section is extended, so that the leg structure is at its full height, the axis of rotation of the pulley 36 will be disposed at a point below the attachment of the flexible rope element 32 to the lower leg section. With this arrangement, an operator may independently raise and lower each end of the platform while being stationed upon the platform. It will be seen that each of the legs is independently extensible and retractable and that the upper leg section may be lowered with respect to its associated lower leg section by actuation of the pawl release element 34.

In use, the scaffold 10 will be unfolded from a collapsed position so that the leg structures are disposed in substantially right angular relation with respect to the platform. The brace members 24 are latched in aligned relation wherein an operator may extend each of the legs to a predetermined desired height. This is accomplished by revolving each of the winch winding shafts 31 so that the upper leg section of each leg structure is moved in vertical sliding fashion relative to the lower leg section. The platform 11 will have been extended to the proper length.

If, for example, the scaffold is used to facilitate painting of an interior structure, the scaffold will be elevated to a height to permit the painter to paint the ceiling. The scaffold may be progressively lowered to a lower predetermined height by release of the small release element 31 and manipulation of the winding shaft 31. This operation can be accomplished by the operator while he is stationed upon the platform.

When it is desirable to move to a new location, the leg structures are retracted and thereafter folded and the platform 11 is also moved to be in the retracted position. Thus the entire scaffold is reduced to a collapsed structure of relatively small compass to permit ready portability thereof. The scaffold may thereafter be unfolded and erected to an operative position. It should be noted that inasmuch as the leg structures 15 are independently foldable, one of the leg structures may be folded to a collapsed position while the other leg structure may be unfolded to the erect operative position. With this arrangement, one end of the scaffold may be positioned upon the selected step of a stairway while the other leg structure serves to support the upper end of the scaffold. Quick leveling of the platform may be readily accomplished by the winch mechanism of the vertically disposed leg structure. Thus the scaffold may be leveled with respect to any given selected step to thereby permit the scaffold structure to be used for work in diflicult places such as stairway areas and the like. Heretofore, exact leveling of the scaffold platforms of comparable devices could not be accomplished.

It is pointed out that the width of the upper leg sections of each leg structure is of a width corresponding to the width of its associated platform section. With this arrangement, not only are pairs of slide structures defined by the upstanding structural leg elements of the upper section but these structural leg elements also cooperate with the brace members 24 to develop the supporting strength of the platform 11.

Since the brace members are movable with the upper leg section, the reinforcing effect thereof is maintained by extensible and retractable movement of the upper leg section with respect to the platform.

It will, therefore, be seen from the foregoing that a novel scaffold including a platform of generally flat configuration which may be readily extended and retracted, and having leg structures which are arranged and con structed to be vertically extended and retracted by an operator stationed upon the scaffold platform has been provided.

It will also be seen that this novel scaffold not only is variously adjustable as to length and height but is also foldable and retractable into a structure of small cornpass thereby enabling a single user to transport the scaffold from place to place.

From the foregoing, it will be seen that the novel scaffold is provided with winch means for permitting each of the leg structures to be raised and lowered independently of each other thereby enabling a user to support one end of the scaffold upon a surface such as a stairway step or the like while the other leg structure serves to support the other end of the platform.

It will therefore be seen that a novel scaffold which is not only of simple and inexpensive construction but one which functions in a more efficient manner than any heretofore known comparable devices has been provided.

It will, of course, be understood that various changes may be made in the form, details, arrangement, and proportions of the various parts Without departing from the general scope of this invention.

What is claimed is:

1. A collapsible scaffold apparatus comprising a longitudinally adjustable platform including a pair of substantially flat platform sections slidably interconnected together for longitudinal slidable and retractable and extensible movement relative to each other,

a pair of vertically adjustable leg structures each being pivotally connected at its upper end to the outer end of one of said platform sections with pivotal movement between an erect upright position and a collapsed position against the lowcr surface of said plat form,

each of said leg structures including a substantially flat upper leg section and a substantially flat lower leg section interconnected together for vertical extensible and retractable movement relative to each other, each of said lower leg sections having an elongate vertically disposed slide element extending approximately the full length thereof, each of said upper leg sections having an elongate vertically oriented slideengaging structure slidably engaging the slide element of the associated lower leg section and having a length substantially approximating the length of the upper leg section,

a pair of collapsible sectional elongate brace members each extending diagonally between and being pivotally connected at the respective opposite ends thereof to the lower portion of one of the upper leg sections and to the adjacent platform sections, each of said brace members including a pair of brace sections pivotally connected together for movement between extended end-to-end relation and collapsed folded relation,

means for vertically extending and retracting said leg structures comprising a pair of winch mechanisms each being mounted on one of said upper leg sections adjacent the upper end thereof,

each of said winch mechanisms including an elongate flexible element having one end secured thereto and being windable thereon and having the other end secured to the lower leg section of its associated leg structure,

a pair of guide members each being mounted on the lower portion of one of said upper leg sections at a point spaced below the attachment of the flexible elements of the associated lower leg structure,

each of said flexible elements being trained over one of said guide members whereby an operator on the platform may selectively revolve each of the winch mechanisms to independently extend or retract each of said leg structures,

and releasable lock means for releasably locking each of said leg structures against vertical retraction by permitting vertical extension thereof.

2. The structure as defined in claim 1 wherein each of said brace members is provided with releasable locking means for locking said brace sections of each brace member in an extended end-to-end relation.

3. The structure as defined in claim 1 wherein each of the upper leg sections is of a width corresponding substantially to the Width of the adjacent platform section.

References Cited in the file of this patent UNITED STATES PATENTS 962,976 Pence June 28, 1910 1,294,264 Herman Feb. 11, 1919 2,237,543 Berchem Apr. 8, 1941 2,755,144 Simmons July 17, 1956

Claims

1. A COLLAPSIBLE SCAFFOLD APPARATUS COMPRISING A LONGITUDINALLY ADJUSTABLE PLATFORM INCLUDING A PAIR OF SUBSTANTIALLY FLAT PLATFORM SECTIONS SLIDABLY INTERCONNECTED TOGETHER FOR LONGITUDINAL SLIDABLE AND RETRACTABLE AND EXTENSIBLE MOVEMENT RELATIVE TO EACH OTHER, A PAIR OF VERTICALLY ADJUSTABLE LEG STRUCTURES EACH BEING PIVOTALLY CONNECTED AT ITS UPPER END TO THE OUTER END OF ONE OF SAID PLATFORM SECTIONS WITH PIVOTAL MOVEMENT BETWEEN AN ERECT UPRIGHT POSITION AND A COLLAPSED POSITION AGAINST THE LOWER SURFACE OF SAID PLATFORM, EACH OF SAID LEG STRUCTURES INCLUDING A SUBSTANTIALLY FLAT UPPER LEG SECTION AND A SUBSTANTIALLY FLAT LOWER LEG SECTION INTERCONNECTED TOGETHER FOR VERTICAL EXTENSIBLE AND RETRACTABLE MOVEMENT RELATIVE TO EACH OTHER, EACH OF SAID LOWER LEG SECTIONS HAVING AN ELONGATE VERTICALLY DISPOSED SLIDE ELEMENT EXTENDING APPROXIMATELY THE FULL LENGTH THEREOF, EACH OF SAID UPPER LEG SECTIONS HAVING AN ELONGATE VERTICALLY ORIENTED SLIDEENGAGING STRUCTURE SLIDABLY ENGAGING THE SLIDE ELEMENT OF THE ASSOCIATED LOWER LEG SECTION AND HAVING A LENGTH SUBSTANTIALLY APPROXIMATING THE LENGTH OF THE UPPER LEG SECTION, A PAIR OF COLLAPSIBLE SECTIONAL ELONGATE BRACE MEMBERS EACH EXTENDING DIAGONALLY BETWEEN AND BEING PIVOTALLY CONNECTED AT THE RESPECTIVE OPPOSITE ENDS THEREOF TO THE LOWER PORTION OF ONE OF THE UPPER LEG SECTIONS AND TO THE ADJACENT PLATFORM SECTIONS, EACH OF SAID BRACE MEMBERS INCLUDING A PAIR OF BRACE SECTIONS PIVOTALLY CONNECTED TOGETHER FOR MOVEMENT BETWEEN EXTENDED END-TO-END RELATION AND COLLAPSED FOLDED RELATION, MEANS FOR VERTICALLY EXTENDING AND RETRACTING SAID LEG STRUCTURES COMPRISING A PAIR OF WINCH MECHANISMS EACH BEING MOUNTED ON ONE OF SAID UPPER LEG SECTIONS ADJACENT THE UPPER ENDS THEREOF, EACH OF SAID WINCH MECHANISMS INCLUDING AN ELONGATE FLEXIBLE ELEMENT HAVING ONE END SECURED THERETO AND BEING WINDABLE THEREON AND HAVING THE OTHER END SECURED TO THE LOWER LEG SECTION OF ITS ASSOCIATED LEG STRUCTURE, A PAIR OF GUIDE MEMBERS EACH BEING MOUNTED ON THE LOWER PORTION OF ONE OF SAID UPPER LEG SECTIONS AT A POINT SPACED BELOW THE ATTACHMENT OF THE FLEXIBLE ELEMENTS OF THE ASSOCIATED LOWER LEG STRUCTURE, EACH OF SAID FLEXIBLE ELEMENTS BEING TRAINED OVER ONE OF SAID GUIDE MEMBERS WHEREBY AN OPERATOR ON THE PLATFORM MAY SELECTIVELY REVOLVE EACH OF THE WINCH MECHANISMS TO INDEPENDENTLY EXTEND OR RETRACT EACH OF SAID LEG STRUCTURES, AND RELEASABLE LOCK MEANS FOR RELEASABLY LOCKING EACH OF SAID LEG STRUCTURES AGAINST VERTICAL RETRACTION BY PERMITTING VERTICAL EXTENSION THEREOF.