GB2244753A

GB2244753A - Platforms for workmen

Info

Publication number: GB2244753A
Application number: GB9007152A
Authority: GB
Inventors: Ronald Thomas Collier
Original assignee: Individual
Current assignee: Individual
Priority date: 1990-03-30
Filing date: 1990-03-30
Publication date: 1991-12-11
Also published as: GB9007152D0

Abstract

A portable platform for supporting a person in an elevated position is composed of a pair of end frames (10). Each end frame (10) has a pair of upstanding legs (13) supported by wheels (16) and joined by cross-pieces (14) like a ladder. The legs (13) of the end frames are hollow and receive complementary legs (24) of further upper frames (25) which can be raised and lowered in a telescopic manner to adopt locations set by locking devices (28). Safety rails engage between the upper frames (25) to provide a safety cage surrounding an operator standing on a base (5) resting on aligned cross-pieces (14) of the end frames (10). The lower ends of the legs (13) of the end frames (10) are pivoted to floor rails and catches and braces lock the legs (13) upright for use or allow the frames (10) to be swung inwards to collapse the platform for storage or transport. <IMAGE>

Description

IMPROVEMENTS IN PLATFORMS The present invention relates to apparatus for providing a portable platform for supporting a person in an elevated position, usually for use in interior or exterior decorating or building work or the like.

Apparatus of this type is described in GB-2,189,536a.

Apparatus in accordance with the invention comprises a pair of end frames each composed of a pair of upstanding legs and a series of spaced-apart cross-pieces which form a ladder like construction, base rails or beams pivotably connected to the lower regions of the frames, catches for locking the end frames in an upstanding disposition relative to the rails, the catches being manually releasable to permit the frames to be pivoted in the direction of the rails to adopt a collapsed folded disposition for transport or storage, and further upper frames each with upstanding legs and one or more cross-pieces the legs of the upper frames being slidably and adjustably located relative to the upper regions of the legs of the end frames.A base on which an operator stands in an elevated position can rest or be fitted onto chosen aligned cross-pieces of the end frames in various height positions. The legs of the upper frames may be linked together with additional safety rails and the upper frames and safety rails can then act as a safety cage and gripping mean for the operator.

Additional bracing straps or the like can be fitted diagonally between the legs of the end frames at the base rails to hold the end frame upright. Preferably the upper frame legs and the end frame legs engage in telescopic manner and locking devices, preferably spring loaded plungers, then lock the respective legs in preselected height positions.

The invention maw be understood more readily and various other aspects and features of the invention may become apparent from consideration of the following description.

An embodiment of the invention will now be described by way of example only, with reference to the accompanying drawings, wherein Figure 1 is a side view of apparatus constructed in the invention; Figure 2 is an end view of the apparatus; Figure 3 is a side view of the one of the toggle levers; Figure 4 is a side view of one of the components parts of the toggle lever; Figure 5 is a side view of the other of the component parts of the toggle lever; and Figure 6 is an enlarged sectional view of one of the locking devices.

Figures 1 and 2 depict apparatus constructed in accordance with the invention in its erected state. As shown the apparatus can be considered as a pair of end frames 10,11 each composed of upstanding support legs 13, interconnected by a series of cross-pieces 14.

Conveniently the cross-pieces 14 are welded to the legs 13, and are spaced apart in a ladder-like configuration. The legs 13 have plates 15 at their lower ends onto which is mounted a wheel assembly 16. Each wheel assembly 16 can be known proprietary item with a wheel 17 which can swivel around an upstanding axis (as (indicated by arrow K) and a lever 18 which serves to lock the wheel 17 selectively. The two frames 10, 11 are also connected at their lower ends to longitudinal beams or rails 19 with the aid of pivot joints 20. The frames 10,11 are selectively locked in an upstanding disposition with the aid of two part toggle levers 21 pivotably connected to the legs 13, and to the rails 19. Figures 3, 4 and 5 depict the toggle levers 21. As shown in Figures 3 to 5 each toggle lever 21 is composed of two components 31,32.The component 31 is pivotably connected to a bracket 38 on one of the frame legs 13 while the component 32 is pivotably connected to one of the longitudinal rails 19. A pivot pin 34 connects the components 31, 32. The component 32 has a relief or cutout portion 35 which receives a bent lug 36 of the component 32 to lock the components 31, 33 rectilinearly.

The components 31, 32 can be released manually by pulling the components 31,31 in the direction of arrow A in Figure 1 and pioting about the pin 34. Additional bracing members 22 are provided to hold the frames 10,11 upright. The members 22 can be detachable from the structure and connected to the rails 19 and the legs 13, e.g. with the aid of thumb screws or pins engaging in apertures. The frame legs 13, are hollow and of square or rectangular cross-section made for example of steel or aluminium. The upper regions of the frame legs 13, receive the respective complimentary legs 24 of upper frames 25. The legs 24 of each of the upper frames 25 are interconnected by a single cross-piece 26 or several cross-pieces. Detachable longitudinal rails 27 fit onto the upper ends of the legs 24.Conveniently the rails 27 have bosses 28 at their ends which fit onto the legs 24 and thumb-screws 29 which enable the rails 27 to be fised in place.

The upper frames 25 can be raised and lowered (arrows B) in relation to the legs 13 in telescopic fashion to adopt one of a number of pre-set positions.

These positions are defined by bores in the legs 24 which receive spring-loaded pegs or plungers of locking devices 28. The constructions of the locking devices 28 is shown in Figure 6.

As shown in Figure 6, each device 28 takes the form of a pin 61 carried by a housing 62 fitted to an inner side face of the associated leg 13 (Figure 1). The pin 61 projects through a hole 65 in the leg 13. The associated inner leg 24 is provided with a series of spaced-apart bores 66 in the wall 12 adjacent the projecting pin 61.

The pin 61 is engaged through one of the bores 66 to lock the legs 13,24 together. A groove 63 in the pin 61 provides a seating for the periphery of the bore 66 in the registry therewith. The pin 61 is pressed inwardly by the force of a spring 69 in the housing 62. The spring 69 engages on an end wall of the housing 62 and on an abutment plate 67 on the pin 61. A knob 68 on the exterior of the pin 61 enables an operator to pull the pin 61 outwards to free the leg 24 and permit adjustment to another bore 66. The devices 28 thus enable the frames 25 to be brought into a desired elevated position.

The apparatus as described is used with a base 5 on which a person can stand in an elevated position.

Conveniently the base 5 takes the form of one or more wooden boards laid onto aligned cross-pieces 14 of the end frames 10,11. Where maximum height is desired the base 5 is placed on the upper most cross-pieces 14 and the upper frames 25 are raised and locked with the locking devices 28. The rails 27 and the cross-pieces 26 then combine to form a safety-rail to surround and protect the person standing on the elevated base 5. The person can also hold onto one of the rails 27 or one of the cross-pieces 26. A person can climb onto the elevated base 5 with the aid of the ladder like crosspieces 14 of either end frame 10,11.

The apparatus can be moves around on the wiiefls 1T when desired but the wheels 1 would be immobilized when the person is standing on the base and working.

The apparatus can easily be dismantled by releasing and removing the rails 27 and the bracing members 22, b unlocking the levers 21 and swinging the frames 10,11 inwardly towards the rails 19. With the apparatus in a collapsed flat stowed in-operative state it can be easily carried around transported or stored.

It is possible to modify the apparatus so that the wheel assemblies 16 are omitted and the apparatus then simply rests on the floor or ground with the plates 15.

In another modification, the wheel assemblies 16 or the plates 15 are mounted on separate support legs engaging in telescopic fashion in the bottom of the frame legs 13. Additional locking devices 28 can then be provided to lock the individual support legs to the frame legs 13 in various height positions. This is particularly useful where the apparatus is to be used on stairs or a sloping or uneven ground surface.

Claims

1. Apparatus for providing a portable platform capable of supporting a person in an elevated position; said apparatus comprising a pair of end frames of ladder-like configuration each composed of a pair of upstanding legs and a series of spaced-apart cross-pieces for supporting a base on which an operator can stand, base rails or beams pivotably connected to the lower regions of the end frames, catches for locking the end frames in an upstanding disposition relative to the rails, the catches being manually releasable to permit the frames to be pivoted in the direction of the rails to adopt a collapsed folded disposition for transport or storage, and further upper frames each with upstanding legs and one or more cross-pieces the legs of the upper frames being slidably and adjustably located relative to the upper regions of the legs of the end frames.

2. Apparatus according to claim 1, and further comprising detachable safety rails for connecting the legs of the further frames together

3. Apparatus according to claim 1 or 2 and further comprising bracing straps for fixing diagonally between the legs of the end frames and the base rails to hold the end frames upright.

4. Apparatus according to claim 1, 2 or 3 wherein the legs of the upper frames and the end frames engage in telescopic manner and locking devices are provided to lock the respective legs together in various pre-selected height positions.

5. Apparatus according to claim 4 wherein the locking devices employ spring-locked plungers which engage in respective spaced apart bores in some of the legs.

6. Apparatus according to any one of claims 1 to 5, wherein the catches take the form of two-part toggle levers.

7. Apparatus according to any one of claims 1 to 6 and further comprising wheel assemblies mounted at the lower ends of the legs of the end frames.

8. Apparatus according to claim 7, wherein the wheel assemblies are mounted on separate support legs engaging in lower ends of the legs of the end frames in telescopic manner and further locking devices to serve to lock the support legs to the frame legs in pre-set relative height positions.

9. An apparatus substantially as described with reference to, and as illustrated in any one or more of the Figures of the accompanying drawings.