AU650203B1 - Improved trestle - Google Patents

Description

650203

AUSTRALIA

PATENTS ACT 1990 P/00/01i1 ReguLation 3.2 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

S

S.

S. S Sb Sb TO BE COMPLETED BY APPLICANT Name of Applicant: STANFORD ROY Actual Inventor- STANFORD ROY Address for Service: MR PETER NICHOLLS, Patent and Trade Mark Attorney, Ellesmere, 5 Ardmillan Road, Moonee Ponds, Victoria 3039, Australia Invention Title: "IPROVED TRESTLE" The following statement is a full description of this invention, including the best method of performing it known to me:- 1- -1 I This invention relates to scaffolding and similar devices including trestles and the like for the supporting of elevated "cat-walks", walk-ways or platforms such as used by painters and plasterers.

Ordinary ladders have been used in the past, but these and other contrivances known and used hitherto have often been cumbersome, inconvenient or unsteady, or have otherwise been found wanting and sometimes unsafe or unreliable for this purpose.

An object of the invention is to provide a support for painters, plasterers and others whose work requires access to ceilings, high walls and other i10 situations necessitating a safe and reliable elevated walk-way or other work oeee platform.

Another object is to provide a support that is sturdy, yet readily portable and easily assembled and dismantled as required.

These and other objects and advantages will become apparent i" hereinafter.

S"A conventional trestle or easel has four legs which, in a "use" condition, S have their feet at the corners of an imaginary rectangle defining a support base.

It is essentially a pair of two-legged elements or parts, hinged together at their tops for relative turning movement between a closed or storage position wherein they are substantially flat one against the other, and the open or "use" position wherein they are at a suitable angle to provide the required quadripodal support base. Brace means such as short length(s) of rope or chain, or hinged arms, prevent the elements from opening more than by a predetermined angle. A sideview of such a trestle in use, therefore, resembles an upper-case letter A of which -2the inclined members are the nearer legs of the respective parts, the cross-member is the brace means, and the apical angle is the maximum angle permitted by the brace.

However, in my trestle device the parts or elements formed by or including the respective pairs of legs are not hinged or otherwise connected but co-operate in an X-formation "sliding joint" whereby legs of one define angled slots adapted to receive legs of the other in a suitably inclined relationship in which they are incapable of any substantially relative turning movement and in which they constitute a sturdy support for a load.

According to the present invention a trestle is characterised by separable elements providing first and second systems of legs assemblable into a use condition of substantially X-formation by relatively sliding and substantially nonrotational movement, providing, for a load, a multipod support base defined by feet of said legs, legs of a second said element defining angled slots to receive upper end portions of respective legs of a first said element, the slots being inclined according to a predetermined angle of said X-formation, and being dimensioned and positioned so to as to prevent further passage of the relevant second leg by abutment of a lower portion thereof against the margin of the slot, and such that when said first wAmd second elements are assembled, with their respective leg systems in the mutually abutting positions, their feet are so related as to define said support base.

But in order that the invention may be better understood, reference will now be made to the accompanying drawings which are to be considered as part of this specification and read herewith. In the drawings: -3- Fig. 1 is a side elevation of a painter at work, standing on a walk-way or platform supported at each end by a trestle according to a practical embodiment of the invention; Fig. 2 is an enlarged and partially cross-sectioned side view of the lefthand part of the structure of Fig.l; Fig. 3 is an end elevation of the structure of Fig. 2, and Fig. 4 is a further enlarged, perspective view of the trestle shown in Figs. 2 and 3 showing the relevant end portion of a walk-way supported thereon in a use condition. The structure will be described primarily by reference to the *o 10 one trestle, it being understood that the other can be essentially the same.

Referring to the drawings in more detail, there are shown a pair of trestles 5, 6 on which rests walk-way 7 the end of which rests upon transverse support 8 fastened between legs 9, 10 of ladder 11 which is the first of a pair of bipod elements that co-operate in a "sliding joint" to form the trestle 5 which is of generally X- or saltire form. Legs 9, 10 represent a "first system" as referred to herein.

"The second or inner element of said pair comprises legs 12, 13 constituting a second system, interconnected near their lower ends by one or more transverse strengthening members 14, and defining, near their upper ends, slots for receiving reduced thickness upper end portions 15, 16 of legs 9, respectivoly. However the dimensions of the slots prevent passage therethrough of the remaining or lower portions of the respective legs 9, 10 and the tops of said lower portions firmly abut against the respective legs 12, 13 of the second element or ladder 11 when the trestle is set up for usa, as seen in Fig. 4.

-4- Rungs 17, 18 are fixed between legs 9 and 10 beneath the level of support 8, to afford convenient access to the end of walk-way 7 resting thereon.

Strut systems 19, 20 join the upper portions 15, 16 of first legs 9, respectively and the lower end portions of corresponding second legs 12, 13 when said legs are assembled in their X-formation as shown in the drawings. Each strut system 19, 20 may consist of a pair of members 21, 22 and 23, 24 respectively, between which spacer blocks such as 25 are adapted to receive the reduced upper end portions of the legs. The upper and lower strut/leg connections 26, 27 respectively may be bolts over the ends of which wing-nuts (not shown) may be fitted. Upward extensions of members 21 to 24 may provide, with the assistance of suitable spacer blocks such as 28 and bolts 29, supports between which may be damped the ends of slide rails 30 for a paint-tray 31.

To dismantle the structure illustrated, tray 31 is removed and bolts 29 loosened to release rails 0 which are lifted away, whereupon walk-way 7 is ::i35 vacated and lifted away from the trestles. Each trestle can thereupon be disassembled as follows: the upper strut/leg connections 26 are loosened and removed and the lower connections 27 simply loosened. The removal of connection 26 enables the first or ladder element 11 to be slidably withdrawn from the element, and the loosening of 27 enables the relevant strut systems 21, 22 and 23, 24 to be turned to a storage condition (not shown) in which they are secured to the respective legs 12, 13 at 32, 33 respectively. This can be done by passing, through holes a'i those points, bolts removed from connections 26, 27.

Exigencies of space may make it desirable to dispense with one trestle, such as in situations wherein one end of a walk-way is required to be near a wall.

That end, rather than being supported by a trestle, may be supported by a simple "wall unit" (not shown in the drawings), resembling an ordinary step-ladder, resting on the floor and leaning against the aforesaid wall.

Clearly, in this position, the wall unit must be able to provide, for the walk-way a support at a height substantially the same as provided by a trestle at the other end, so that the walk-way will be at least approximately horizontal.

Upper parts of the wall unit's legs may have grooves, recesses or the like to receive ends of slide rails 30, and the top end portions i.e. the ends that lean against the wall, may be padded or "fendered" against marking or otherwise Th damaging the wall.

Clearly the support base defined by the feet of legs 9, 10, 12 and 13 is substantially rectangular. For added stability it can be expanded by fixing more S. legs to one or both elements. For example widely splayed props 34, 35 can be attached to latter 11, as best shown in Fig. 4. Additional or alternative fastenings .15 may be provided as desired, such as by cabin hooks attachable between 1.0, 34 and 9, 35 respectively.

0 For purposes of this specification terms such as "upper", "upward", "lower" and "beneath" refer to the invention in a position of use and are not necessarily limiting.

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Claims (9)

1. A trestle characterised by separable elements providing first and second systems of legs assemblable into a use condition of substantially X- formation by relatively sliding and substantially non-rotational movement, providing, for a load, a multipod support base defined by feet of said legs, legs o a second said element defining angled slots to receive upper end portions of respective legs of a first said element, the slots being inclined according to a pre- determined angle of said X-formation, and being dimensioned and positioned so to as to prevent further passage of the relevant second leg by abutment of a lower 10 portion thereof against the margin of the slot, and such that when said first and second elements are assembled, with their respective leg systems in the mutually abutting positions, their feet are so located as to define said support base.

2. A trestle as claimed in claim 1 including a load support element fixed between legs of one or both systems. 5"

3. A trestle as claimed in claim 2 wherein the first element also a ladder and therefor includes one or more transverse rungs beneath the level of the support element to afford convenient access to the end of a walk-way resting on said element.

4. A trestle as claimed in claim 3 wherein the second element is strengthened by one or more members fixed between legs thereof.

A trestle as claimed in any one of the preceding claims including a strut system fastenable between the upper part of a first leg and the lower part of a second leg when said legs are assembled in their X-formation. -7-

6. A trestle as claimed in claim 5 wherein the lower connection, that is to say, the connection of the strut system to the relevant second leg, is by a fastenable and releasable bolt or like pivotal means, and the upper connection, that is to say, the connection of the strut system to the first leg, is fastenable when the legs are assembled, and removable to allow disassembly of the legs by said relative sliding movement.

7. A trestle as claimed in claim 6 wherein the upper connection having been removed and the lower connection loosened, the strut system is pivotable relative to the secondn ember about said lower connection, means being 10 provided for securing them in a storage condition and, when the trestle is again being assembled, allowing the strut to be unsecured and turned to an angle at which it is fastenable to form said upper connection, the upper and lower connections thereupon being securely fastenable.

8. A trestle as claimed in any one of claims 5 to 7 wherein upward 15 extensions of one or more said strut systems provide supports for a system of slide rails for a paint tray or the like. *.b

9. A trestle substantially as herein described with reference to the accompanying drawings. DATED this 20th day of August, 1993 STANFORD ROY By hisP-tent Attorney -8- ABSTRACT A trestle assemblable from separate bipod elements of which legs are mutually slidable into a non-rotational saltire formation. *9*9 9* 9 9 99 *4*9 99 #9 99 9 9*99 S. 9* 9 9 9* 9 9I*9* 99 99 9 9 *4 .9. -9-