US3870124A

US3870124A - Scaffold ladder structure

Info

Publication number: US3870124A
Application number: US432081A
Authority: US
Inventors: Ivy J Howard
Original assignee: Individual
Current assignee: Individual
Priority date: 1974-01-09
Filing date: 1974-01-09
Publication date: 1975-03-11
Anticipated expiration: 1992-03-11
Also published as: CA1043838A

Abstract

A ladder vertically disposed within the confines of a scaffold permitting ascension of assembled scaffolding by a worker in a safe manner. Connector means includes clamps retaining the ladder in an inwardly offset relationship to the adjacent scaffold frame member. The ladder in turn supports a rectangular framework which defines an accessway extending through scaffold planking. The framework jointly supports reduced planks terminating adjacent the accessway along with guard rail posts forming a protective enclosure preventing inadvertent entry by a worker. The ladder structure may be readily detached from the scaffolding and disassembled without tools for compact transport.

Description

Howard Mar. 11, 1975 1 1 SCAFFOLD LADDER STRUCTURE Ivy J. Howard, 2020 Minda Drive, Eugene, Oreg. 97401 [22] Filed: Jan. 9, 1974 [21] Appl. No.: 432,081

[76] Inventor:

3,726,362 4/1973 Puckett 182/178 Primary Examiner-Reinaldo P. Machado Attorney, Agent, or FirmJames D. Givnan, Jr.

[57] ABSTRACT A ladder vertically disposed within the confines of a scaffold permitting ascension of assembled scaffolding by a worker in a safe manner. Connector means includes clamps retaining the ladder in an inwardly offset relationship to the adjacent scaffold frame member. The ladder in turn supports a rectangular framework which defines an accessway extending through scaffold planking. The framework jointly supports reduced planks terminating adjacent the accessway along with guard rail posts forming a protective enclosure preventing inadvertent entry by a worker. The ladder structure may be readily detached from the scaffolding and disassembled without tools for compact transport.

7 Claims, 3 Drawing Figures SCAFFOLD LADDER STRUCTURE BACKGROUND OF THE INVENTION The present invention relates generally to scaffolding and particularly to ladder structure usable therewith.

Conventional scaffolding may include components having ladder rungs formed integral with the scaffold frames. Workers climbing such scaffolding must ordinarily climb exteriorly of the scaffold structure to avoid planking and normally with no cage or safety means encompas'sing the climbing worker. Accordingly, a misstep by the worker may result in an unbroken fall to the ground surface. Attempts to enclose such integrally formed ladders in compliance with recent safety requirements have not been practical and at present no satisfactory solution to the problem has been rendered.

Other attempts at providing integrally formed ladders include the provision of an additional'standard closely adjacent a scaffold frame leg with rungs extending therebetween. A safety problem exists in providing safe entry onto scaffold planking from the exteriorly located ladder. Further, weight, size, cost of manufacture and portability of the scaffolding are all adversely effected.

SUMMARY OF THE INVENTION man would be broken by scaffold structure in a manner not dissimilar from a ladder cage structure.

The present ladder may be removed from supported engagement with the scaffold to permit stacking and transport of the conventional tubular scaffold components in the usual manner. The ladder structure of the present invention-equally lend themselves to convenient transport.

Important objectives of the instant invention include the provision of: ladder structure adaptable for use with all conventional scaffolding; ladder structure contributing'to safe working conditions by at all times permitting ascending or descending of scaffolding within the confines of scaffolding structure; ladder structure permitting worker access to a scaffold platform without requiring the climbing over or through structural bracing of the scaffold; ladder structure which may be incorporated or removed without jeopardizing scaffold integappliedreference numerals indicate parts similarly identified in the following specification, the reference numeral 1 indicates generally an assembled scaffold of conventional scaffolding comprising tubular end frames 2 interconnected by diagonal cross braces 3. Horizontal crossmembers 4 of each frame constitute supports for planking which provides a platform P for the workmen. The scaffold 1 is most commonly assembled in conjunction with adjacent like scaffolds to the height required by the job at hand.

The scaffold module so described may rest on the ground surface at GI; or, alternatively, the vertical frame members 2 may be supported by like members of a subjacent scaffold module with the tubular ends thereof being in inserted engagement with pins of the type indicated at 6 projecting upwardly from the subjacent scaffold frame members. In FIG. 1, the scaffold module may support four guard rail posts 7 with guard rails 8 extending therebetween enclosing a work area above the platform. The guard rail posts normally include offset, depending segments (not shown) which additionally brace the post against horizontally applied loads. The foregoing description is generally applicable to all of the commonly used scaffolding with a wide variety of scaffolding sizes being available with variation in certain features which are not of present importance.

The ladder structure embodying the present invention is indicated generally at 10 and attaches to a hori-, zontal crossmember 4 of the scaffolding structure. With continuing reference to the ladder structure, a pair of connector plates 11 include semi-circular couplings 12 in seated engagement with crossmember 4 with lock pins 13 in place through said couplings. The

inwardly extending connector plates 11 are each aperv tured at 11A to receive the upper end of a ladder rail at 17 to retain same against horizontal displacement. Ladder rungs are indicated at 18. In instances where the scaffold module is in supported contact with the ground, the lowermost ends of rails 17 will be supported by ground contact, such contact also securing said ends against horizontal displacement. Where the scaffold module is supported by a subjacent scaffold module, pins as at 20, integral with the upper end of each rail, will confine the superjacent rail against such displacement with vertical loading being imparted to the supporting surface by a series of coupled ladder rity regardless of overall height of assembled scaffolding.

BRIEF DESCRIPTION OF THE DRAWINGS DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT With continuing reference to the drawings wherein.

rails.

In supported attachment with the above described ladder is a combination plank and guard rail support framework comprising a pair of horizontally spaced post supports 21 supported by tubular brace members 22 which in turn are carried by rung and rail engaging components indicated at 23 and 24. Components 23 may be of inverted hook shape welded to a vertical connector 25 which carries at its bottom end rail engaging component 24. The last mentioned component is curved to prevent lateral displacement from a rail 17. A horizontal member 26 of the framework interconnects the post supports 21 and additionally serves to support the end or ends of platform planks 27 as viewed in FIG. 2 with additional planking comprising platform P being indicated at 28. With continuing reference to FIG. 2 a worker access area is indicated at 30 through which workers may climb or descend from the scaffold platform area.

For the purpose of protecting the workers against accidentally stepping into the open area 30, I provide a pair of conventional guard posts 31 in inserted engagement with pins 32 integral with post supports 21. Said guard posts are of the conventional type including a depending offset portion (not shown) for added rigidity. A third guard post at 33 is coupled with the exposed pin 20 projecting upwardly from the upper end of a ladder rail. Safety chains at 34 extend horizontally intermediate the two guard rail posts 31 and terminate at post 33 to close off the space above access area 30. Accordingly, a relatively small area of the platform surface is taken up by the present ladder structure with the ladder area being closed off by the safety chains 34 for protection of the workers. The chains 34 are provided with snap fasteners to facilitate entry of a worker onto the platform surface from the ladder area 30.

The present ladder structure may be installed with or subsequent to the erection of the scaffolding. The small number of highly portable components enables rapid incorporation of the ladder structure into the scaffolding as well as convenient removal during scaffolding disassembly. The structural integrity of the scaffold is unimpaired by the present ladder structure. Further, the ladder structure is believed to be in compliance with known safety requirements.

While I have shown but one embodiment of the invention, it will be apparent to those skilled in the art that the invention may be embodied .still otherwise without departing from the spirit and scope of the invention.

Having thus described the invention, what is desired to be secured under a letters Patent is:

1. Ladder structure for attachment interiorly of a scaffold, said ladder structure comprising,

a ladder offset inwardly within the scaffold confines,

connector means extending intermediate a scaffold member and the upper end of the ladder securing the ladder against displacement, said connector means detachably mounting the ladder to said scaffold member, and

a framework in supported engagement with the upper end of said ladder and defining therewith an accessway for workers, said framework adapted to support guard rail posts of a protective enclosure above said accessway to prevent inadvertent entry by a worker on the scaffold work surface.

2. The ladder structure as claimed in claim 1 wherein said connector means includes clamps in detachable locked engagement with the scaffold member.

3. The ladder structure as claimed in claim 2 wherein said connector means is apertured oppositely from the clamps for inserted reception of the ladder rail ends.

4. The ladder structure as claimed in claim 1 wherein said framework projects inwardly relative to the ladder and said scaffold structure, post supports carried by the inner end of said framework for supporting engagement with guard rail posts of a protective enclosure.

5. The ladder structure as claimed in claim 4 wherein said framework includes a plank supporting horizontal member for supporting plank ends adjacent the accessway.

6. The ladder structure as claimed in claim 5 wherein said framework includes hook members for rested engagement with ladder rung structure.

7. The ladder structure as claimed in claim 6 wherein said framework additionally includes brackets in rested engagement against ladder rail structure.

Claims

1. Ladder structure for attachment interiorly of a scaffold, said ladder structure comprising, a ladder offset inwardly within the scaffold confines, connector means extending intermediate a scaffold member and the upper end of the ladder securing the ladder against displacement, said connector means detachably mounting the ladder to said scaffold member, and a framework in supported engagement with the upper end of said ladder and defining therewith an accessway for workers, said framework adapted to support guard rail posts of a protective enclosure above said accessway to prevent inadvertent entry by a worker on the scaffold work surface.