US3480110A - Extendable scaffold - Google Patents

Description

Nov. 25, 1969 R. c. COLEMAN EXTENDABLE SCAFFOLD Filed Jan 4, 1968 INVENTOR RONALD C. COLEMAN ATTORNEY United States Patent 3,480,110 EXTENDABLE SCAFFOLD Ronald C. Coleman, 1323 N orthlake Drive,

Richardson, Tex. 75080 Filed Jan. 4, 1968, Ser. No. 695,797 Int. Cl. E04g 1/22, 7/00 US. Cl. 182184 '11 Claims ABSTRACT OF THE DISCLOSURE Spaced apart upright members are connected by a horizontal bar which supports end portions-of an elevated scaffold platform. Parallel twin sleeves are pivotable around the axis of the horizontal bar to a position wherein one of the sleeves may receive an end portion of an extension rod. When received by the sleeve, the extension rod acts as a cantilever extension of the horizontal bar to receive an additional scaffold platform. A base member is pivotally connected to one of the upright members to provide additional support to the structure when the extension rod is in use.

Field of the invention This invention relates to scaffolds, and more particularly to the use of scaffold extension structure to provide extended width operation Without moving previously erected scaffolding.

The prior art Scaffolds are used for a variety of applications in building construction, and particularly in construction work such as plastering, painting and the like. Fully assembled scaffolds are relatively cumbersome and heavy, and thus scaffold accessories have been heretofore developed wherein the effective height and Width of a scaffold can be extended without moving the entire scaffold assembly. One of the most common methods of extending the effective width of the scaffold has been to add on additional support members which extend laterally from the scaffold tosupp'ort additional scaffold boards. Examples of such systems are described in US. Patent 835,059, issued Nov. 6, 1906; US. Patent 2,897,013, issued July 28, 1959; and US. Patent 3,245,495, issued Apr. 12, 1966. The extension members utilized in these prior systems have not been completely satisfactory with respect to ease of installation, and have often been limited in-length of lateral extension available due to the fact that the extended length has tended to unbalance the existing scaffold.

Summary of the invention In accordance with the present invention, a scaffold may be easily and quickly provided with an extended lateral width without unbalancing the existing scaffold assembly. At least two spaced apart upright members are joined by a horizontal bar which supports an elevated scaffold platform. A member extending parallel to the horizontal bar is provided which receives an end of an elongated rod to support the rod as a cantilever extension of the horizontal bar. A base member is mounted on one of the upright members for pivotal movement to a position of support when the rod is received by the member extending parallel to the horizontal bar.

In another aspect of the invention, structure is provided to enable vertical extension of the upright members, and the pivotal base member is vertically adjustable to compensate for variations in the surface supporting the scaffold.

3,480,110 Patented Nov. 25, 1969 "ice The drawings FIGURE 1 illustrates the present scaffold in its normal operating position; and

FIGURE 2 illustrates the scaffold in a vertically and laterally extended position.

Description of the preferred embodiment Referring to FIGURE 1, a pair of cylindrical upright members 10 and 12 include horizontal bases 14 and 16 for vertical support thereof. Brace members 18 extend at an angle from the base 14 and are attached to the upright member 10. Similarly, braces 20 extending from the base 16 are connected to the upright member 12. A pair of cylinders 22 and 24 are rigidly connected by horizontal bars 26, 28, and 30. Cylinder 22 is concentrically disposed over the upright member 10 and rests at its lowermost end on the upper surface of the braces 18. Similarly, cylinder 24 receives the upright member 12 and rests at its lowermost end on the upper surface of the braces 20. Horizontal bars 26, 28 and 30 provide support for end portions of scaffold boards 31. The other ends of the boards 32, not shown, are supported by a similar scaffold structure to provide a scaffold platform at the desired level.

A pair of hollow, cylindrical sleeves 32 and 33 are mounted on the horizontal bar 28. Sleeves 32 and 33 are integrally connected along a common line of contact, with the sleeve 32 being loosely mounted on bar 28 so that the sleeve 33 may be pivoted about the axis of the bar 28.

Holes 34 are provided in the upper portion of the upright members 10 and 12 for reception of suitable pins (not shown) in order to secure the scaffold as an integral assembly to allow the entire assembly to be moved.

Holes 35 are provided in the lower end of the cylinders 22 and 24. A pin 36 is supported by a suitable chain 37 from each of the cylinders 22 and 24. A pin 38 is supportedby a chain 39 depending from the brace 20. A base leg 40 and a brace 42 are connected to a cylinder 44 which is pivotally connected about the lowermost end of the upright member 12. A hole 46 is provided in the cylinder 44 for registration with a hole (not shown) in the lowermost portion of the upright member 12.

FIGURE 2 illustrates the present scaffold in a vertically extended and laterally extended position. The cylinders 22 and 24 have been moved upwardly along the upright members 10 and 12 and fastened in place by inserting the pins 36 through selected ones of the holes 35 which are in registration with holes 48 in the upright members 10 and 12. Additional scaffold boards 50 are shown in position on the upper horizontal bar 26.

When it is desired to laterally extend the effective length of the scaffold without moving the relatively heavy upright members 10 and 12 and their associated structure, the hollow sleeve 33 is pivoted about the axis of the horizontal bar 28 to a position generally horizontal to the bar 28. A rod 56 of considerable strength is inserted through the hollow sleeve 33. Rod 56 abuts against portions of cylinders 22 and 24 at points generally designated at 57 so that the rod 56 is securely retained within the hollow sleeve 33. The end of the rod 56 extends laterally beyond the existing scaffold to serve as a cantilever extension of the horizontal bar 28. Additional scaffold bars 58 are then placed on the extended end of the rod 56 to effectively lengthen the width of the scaffold. While sleeves 32 and 33 have been shown of relatively large diameters for ease of illustration, it will be understood that their diameters could be smaller in actual practice to eliminate any play when rod 56 is installed.

To prevent the scafiold from becoming unbalanced when the rod 56 is installed in the position shown in FIG- URE 2, the base 40 is pivoted to a position generally parallel to the rod 56. The position of the cylinder 44 along the lowermost end of the upright member 12 may be varied to adjust for irregularities in' the surface supporting the scaifold. The pin 38 is then disposed through the hole 46 to secure the base 46 in the desired position.

Whereas the present invention has been described in detail with respect to a specific embodiment thereof, it is to be understood that various changes and modifications will be suggested to one skilled in the art, and it is intended to encompass such changes and modifications in the appended claims. 7

What is claimed is:

1. In a scafiold assembly for supporting an elevated platform, the combination comprising:

(a) a frame having a base and a superstructure supporting at least one elevated horizontal bar,

(b) a rod parallel and adjacent to said bar extending from within the horizontal span of said base to a point outside the span of said base, and

(c) a tube-like member rotatably supported by said horizontal bar for extending parallel to and adjacent said horizontal bar, said tube-like member receiving and supporting said rod as a cantilevered extension of said horizontal bar.

2. The combination of claim 1 wherein said tube-like member is mounted for pivotal movement about the axis of said horizontal bar, whereby said rod is secured within said member due to abutment against at least one of said upright members.

3. The combination of claim 2 wherein said tube-like member comprises a pair of integral parallel hollow sleeves, one of said hollow sleeves being disposed about said horizontal bar and the other of said hollow sleeves receiving the end portion of said rod.

4. The combination of claim 1 and further comprising:

base means mounted on the lower end of one of said upright members and pivotable about the axis of said one upright member between a position generally perpendicular to the axis of said horizontal bar and a position parallel to the axis of said horizontal bar when said rod is installed as a cantilever extension.

5. The combination of claim 4 wherein said base means is securable to any one of a plurality of points along the axis of said one upright member.

6. The combination of claim 1 wherein said upright members are vertically adjustable in height.

7. A scaffold comprising:

(a) a pair of spaced apart upright members joined by a horizontal bar adapted to support a scaifold platform,

(b) hollow sleeve means having first portion for receiving a length of said horizontal bar and a second portion pivotable about the axis of said horizontal bar, and

(c) a rod having a length greater than the spacing between said upright members and adapted to be re ceived by said second portion of said hollow sleeve means to extend outwardly as a cantilever extension of said horizontal bar for support of an additional scaffold platform.

8. The scaffold of claim 7 wherein said rod abuts against a portion of each said upright members when said rod is received by said second portion.

9. The scaffold of claim 7 and further comprising:

a base portion pivotally connected to the lower end of one of said upright members for movement to a position generally parallel to said horizontal bar when said rod is received by said second portion of said hollow sleeve means.

10. The scafiold of claim 7 wherein said hollow sleeve means comprises:

a pair of hollow cylinders integrally connected along a common parallel line portion.

11. A scaffold comprising:

an H-frame having a base and an elevated horizontal cylindrical spacer bar,

a unitary support formed of two parallel tangent hollow pipes, a first of which is threaded over said bar,

an extension cylinder slidable through the second of said pipes and extending beyond the limits of said H-frame, and

a foot rotatably mounted at the base of said H-frame and adapted to be secured in position below said cylinder outside said H-frame.

References Cited UNITED STATES PATENTS 485,463 11/1892 Ennis 182-132 557,501 3/18'96 Ennis 182132 840,636 l/ 1907 Lillow 182-178 1,409,559 3/1922 McLeod l82130 2,572,928 10/1951 Hawes 182178 REINALDO P. MACHADO, Primary Examiner US. Cl. X.R. 182-178, 132

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