US 3441974 A
Abstract available in
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Description (OCR text may contain errors)
H. T. DEAN,
ADJUSTABLE LEG SUPPORT May 6, 1969 Sheet Filed Aug. 31. 1967,
HOLLIE THOMAS DEAN ATTORNEY Sheet Filed Aug. 31, 1967 HQLL/E THOMAS DEAN ATTORNEY ,44l,974 Umted States Patent cc patentemlfi,
FIGURE 5 is a bottom plan view of the adjustable leg 3,441,974 support;
ADJUSTABLE LEG SUPPORT Hollie Thomas Dean, 107 N. Artizan St., Williamsport, Md. 21795 Filed Aug. 31, 1967, Ser. No. 664,788 Int. Cl. 1360b 33/06, 33/00, 33/04 US. C]. 1633 6 Claims ABSTRACT OF THE DISCLOSURE A leg support including a wheel providing a mobile support and a bell-shaped foot member yieldably supported in an elevated position around the wheel, when said wheel is in an operative surface engaging position. A nut which is threadedly mounted on the post of the wheel fork functions to displace the foot member downwardly into a surface engaging position and to elevate the wheel to provide a stationary leg support of substantial area and which is capable of flexing to conform to inclined supporting surfaces.
Background of the invention This invention relates to the art of adjustable leg supports of scaffolds, tables and similar structures.
The prior art discloses supporting legs with retractable casters and other supporting legs which may be raised or lowered relative to foot members to compensate for differences in elevation of surface areas engaged by different foot members of a scafiold.
Summary It is a primary object of the present invention to provide an adjustable leg support for a scaffold or similar structure including a wheel which may be employed as a mobile leg support or a foot member which may be displaced downwardly to a position below and around the wheel to provide a stationary leg support having a substantial area in contact with a supporting surface.
Another object of the invention is to provide an adjustable leg support which eliminates the need for brakes on the wheels of a scaffold or a similar structure.
A further object of the invention is to provide a leg support which may be extended or retracted relative to the leg with which it is associated to compensate for variations in elevation of a supporting surface.
Still a further object of the invention is to provide a leg support wherein the foot member is capable of flexing, when in an operative position, to compensate for an uneven or inclined surface on which the foot member rests.
Various other objects and advantages of the invention will hereinafter become more fully apparent from the following description of the drawings, illustrating a presently preferred embodiment thereof, and wherein:
Brief description of the drawings FIGURE 1 is a fragmentary side elevational view showing portions of two scaffold legs, each equipped with an adjustable leg support;
FIGURE 2 is an enlarged fragmentary vertical sectional view, partly in elevation, taken substantially along the line 22 of FIGURE 1;
FIGURE 6 is an enlarged fragmentary vertical sectional view, partly in elevation, taken substantially along the line 66 of FIGURE 2, and
FIGURE 7 is a fragmentary side elevational view showing the foot member of the leg support engaging an inclined surface.
Description of the preferred embodiment Referring more specifically to the drawings, the adjustable leg support in its entirety and comprising the invention is designated generally '10 and includes a wheel fork -11 on which a wheel 12 is journaled. A threaded post 13 is fixed to and extends upwardly from the fork 11 and has an upper portion fitting slidably in the lower end of a tubular leg 14 of a scaffold or other suitable supporting structure. FIGURE 1 shows two such legs 14 connected by braces v15 and which may constitute a part of a scaffold of otherwise conventional construction. Each leg 14 is shown supported by one of the adjustable leg supports 10 and it will be understood that each of the other legs of the scaffold or other supporting structure will be similarly supported.
A nut '16 threadedly engages the post 13 and has a flat upper side 17 on which the lower end of the leg 14 rests. It will be readily apparent that the nut 16 may be adjusted lengthwise of the post 13 to vary the elevation of the leg 14 relative to the wheel 12 or to a foot member '18, hereinafter to be described, to compensate for differences in elevation of different parts of a supporting surface 19 engaged by the different leg supports .10. The nut 16 is preferably provided with four equally spaced outwardly projecting handles 20.
The foot member 18 is substantially bell-shaped and of a size to accommodate therein the wheel 12. The foot member '18 is preferably formed of metal and includes an upper annular portion 21 the wall of which is relatively thin and somewhat flexible and which has an upwardly facing concave top central portion 22 surrounding a central top opening 23, partially defined by an annular depending boss 24. A second nut 25 is threadedly mounted on the post .13, above the foot member 18 and beneath the nut 16, and includes handles 26, corresponding to the handles 20. The nut 25 differs from the nut 16 in that it has a convexly rounded bottom surface 27 which conformably fits in the cavity 22.
A collar 28 is fixed around the post 13, above and adjacent the wheel fork 11, in any suitable manner as by welding, as indicated at 29, and has an upwardly facing annular recess 30 providing a seat for the bottom convolution of a compression spring 31 which is disposed around the post 13 and extends upwardly from the collar 28.
The upper end of the spring 31 is disposed around the boss 24 and bears against the underside of the recessed portion 22.
The bottom portion 32 of the foot member 1 8 is thickened radially both inwardly and outwardly thereof to provide an annular flat bottom surface 33 of substantial radial width to which may be secured an annular pad 34 of the same width which is preferably formed of rubber. The bottom portion 32 and pad 34 define a central bottom opening 35 of the foot member having a diameter somewhat less than the diameter of the wheel 12. Said portions 32 and 34 are provided with diametrically opposed notches 36, as best seen in FIGURE 5, the distance between the extremities of which is slightly greater than the diameter of the wheel 12.
From the foregong, it will be apparent that with the nuts 16 and 25 detached from the post 13, that said post 13, that said post can be inserted upwardly through the opening 35 an the opening 23 of the foot member 18, to engage the upper part of the spring 31, carried by the post, around the boss 2 and against the underside of the recessed portion 22, as best illustrated in FIGURE 6. This is accomplished with the wheel 12 aligned with the notches 36, so that the wheel can pass upwardly through said notches and the opening 35 and be thereafter turned with the post 13 to a position at an angle to the notches 36. The nut 25 and thereafter the nut 16 are then applied over the upper end of the post 13 and the upper end of the post is then inserted in the lower end of the leg 14. The nut 16 is adjusted to properly elevate the leg 14, as heretofore described.
Assuming that a leg support is thus applied to each leg 14, if the scaffold or other supporting structure of which the legs form a part is to be immovably positioned, the nut of each leg support is advanced downwardly on the post 13 to cause the convex bottom surface 27 thereof to exert pressure against the concave surface 22 for displacing the foot member 18 downwardly and for compressing the spring 31, so that the wheel 12 will be elevated relative to the foot member 18 and the bottom surface of the pad 34 will rest on the supporting surface 19, to provide an annular surface of substantial area in contact with the surface 19 which will afford a stationary support.
As seen in FIGURE 6, the opening 23 is of sufficient size to afford clearance around the post 13 and said post is maintained centered in said opening by engagement of the surface 27 with the surface 22. Accordingly, should the portion of the surface 19 engaged by the pad 34 be disposed at an incline relative to other portions of said surface, engaged by the pads 34 of the other leg supports 10, the upper portion 21 of the foot member 18 may flex sufliciently, as illustrated in FIGURE 7, so that the pad 34 will rest flush against the inclined part of the surface 19 to provide a stable support for the foot member.
When it is desired to move the supporting structure from one location to another, it is merely necessary to manually turn the nut 25 of each leg support for moving it upwardly from its position of FIGURE 2 to its position of FIGURE 3, to allow the spring 31 to expand and lift or elevate the foot member 18 out of contact with the surface 19 and so that the lower portion of the wheel 12 will protrude through the opening 35 and be in contact with the surface 19 to provide a mobile support for the leg support.
Various modifications and changes are contemplated and may be resorted to without departing from the func- 1 tion or scope of the invention.
1 claim as my invention:
1. An adjustable support for a tubular leg of a supporting structure comprising a wheel fork, a wheel journaled therein, ing upwardly from the wheel fork and having an upper end fitting slidably in the lower portion of a tubular leg, a stop carried by the post on which the lower end of the leg rests, a hollow bell-shaped foot member having a top central portion provided with an opening through which the post extends, a spring stop fixed to the post,
a threaded post fixed to and extendabove and adjacent the wheel fork, a coiled compression spring disposed around a part of the post having a lower end resting on said spring stop and an upper end bearing against a part of the inner side of the foot member around said opening for supporting said foot member in an elevated position, said foot member having a bottom opening through which a part of the wheel projects from the interior of said foot member for contacting a Supporting surface to provide a mobile support for the adjustable leg support, and a nut threadedly engaging the post above the foot member and beneath the leg engaging stop, said nut being movable downwardly on the post to engage and displace the foot member downwardly and to compress said spring for moving the foot member into engagement with the supporting surface and for elevating the wheel into the foot member.
2. A leg support as in claim 1, said foot member having a radially enlarged annular bottom portion surrounding and defining said bottom opening thereof and engaging the supporting surface when the wheel is elevated.
3. A leg support as in claim 2, said bottom portion having an annular surface engaging traction pad secured to its underside.
4. A leg support as in claim 3, said bottom portion and pad having diametrically aligned notches opening into said bottom opening and having a diameter, as measured between the extremities thereof, greater than the diameter of the wheel and through which the wheel is movable into and out of the foot member.
5. A leg support as in claim 1, said leg engaging stop comprising a nut threadedly adjustable on the post for varying the elevation of the leg relative to the foot memher and wheel.
6. A leg support as in claim 1, said top portion of the foot member having an upwardly facing concave surface surrounding the first mentioned opening of the foot member, said nut having a convex underside conformably engaging in said concave surface, said top opening being larger in diameter than the post and being maintained concentrically therearound by engagement of said convex surface with the concave surface, and the wall of the upper portion of the foot member being thin relative to said annular bottom portion and formed of a material to permit flexing thereof to enable the foot member to flex relative to the post whereby the bottom surface of the foot member may assume an inclined position relative to the post to engage an inclined portion of the supporting surface.
References Cited UNITED STATES PATENTS 2,655,387 10/1953 Cramer 16-33 2,176,551 10/1939 Salem 1633 BOBBY R. GAY, Primary Examiner.
DORIS L. TROUTMAN, Assistant Examiner.
US. Cl. X.R.