AU736211B2

AU736211B2 - Stabilising and handrail assemblies for trestles

Info

Publication number: AU736211B2
Application number: AU21190/99A
Authority: AU
Inventors: Thomas Tucker
Original assignee: PLANK MAGIC Pty Ltd
Current assignee: PLANK MAGIC Pty Ltd
Priority date: 1998-03-13
Filing date: 1999-03-15
Publication date: 2001-07-26
Anticipated expiration: 2019-03-15
Also published as: AU2119099A

Description

P/00/011 Regulation 3.2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Invention Title: "STABILISING AND HANDRAIL ASSEMBLIES FOR TRESTLES" The following statement is a full description of this invention, including the best method of performing it known to us: 2

TITLE

"STABILISING AND HANDRAIL ASSEMBLIES FOR TRESTLES" FIELD OF THE INVENTION THIS INVENTION relates to stabilising and handrail assemblies for trestles.

BACKGROUND OF THE INVENTION Generally, workmen such as builders, electricians, painters and the like are required to work at substantial heights above the ground level or floor of a building. In order to work at such heights, these workmen generally employ temporary supporting frameworks, including scaffolding, trestles and the like.

With regard to trestles, a single horizontal plank, for example a solid timber or prefabricated aluminium plank, is commonly disposed between a pair S"of ladder-like support frames to provide an elevated 20 platform.

Tougher Occupational and Health Safety Regulations, and the increased likelihood of medical claims for work injuries, has led to the need to ensure the stability of the trestles supporting the platform; and the provision of handrails surrounding the working areas on the platform.

OBJECT OF THE INVENTION It is a preferred object, in one aspect of the present invention, to provide a stabilising assembly for a trestle.

It is a further preferred object to provide such a stabilising assembly which prevents the trestle tipping to one side.

It is a further preferred object, in a second aspect of the present invention, to provide a handrail assembly for a plank (or planks) supported by two or more trestles.

It is a still further preferred object to provide such a handrail assembly which can be linked to similar handrail assemblies for adjacent planks.

It is a still further preferred object to provide a handrail assembly where the handrails are supported by posts incorporated in the stabilising assemblies for the trestles.

Other preferred objects of the present invention will become apparent from the following description.

•go.

tJSUMMARY OF THE INVENTION In one aspect, the present invention resides in a stabilising assembly for a trestle including: a main post connectable to the trestle at, or adjacent, a joint connecting a pair of spreadable stiles of the trestle; a spreader bar connectable to the stiles and to the main post; and means for stabilising the assembly against ego• outward movement of the main post.

Throughout this specification, unless the context requires otherwise, the words "comprise", N "comprises" and "comprising" will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

Preferably, the main post comprises a cap connectable to upper end portions of the spreadable stiles.

Suitably, the cap, in use, extends below upper surfaces of the upper end portions except on an outer side of-the spreadable stiles.

Suitably, the main post comprises a cross member spaced below the cap and engageable with the spreadable stiles.

Suitably, the spreader bar comprises compression means adapted to compress the outer surfaces of the spreadable stiles.

Preferably, the compression means comprises a pair of clamping jaws.

Preferably, the stabilising means comprises a side brace, having a ground-engaging foot or feet, connectable to the main post and extendable substantially laterally of the plane of spreading of .o the stiles.

Preferably, the side brace and the main post are interconnected by a support member to (optionally selectively) maintain an angular relationship between the main post and the side brace.

Suitably, the support member comprises a Imouth into which an upper portion of the side brace is 20 engageable.

The support member suitably comprises an elongate angular section which is preferably o*e.

substantially U- or V-shaped in cross section.

Preferably, the mouth comprises an angular 25 slot in a face of the elongate section.

Suitably, the upper portion of the side brace comprises a compression means adapted to compress an outer surface of the support member to engage the side brace with the support member.

The compression means preferably comprises a clamp assembly including a threaded shaft and nut, the shaft being positionable within the slot, and the nut being engageable with a surface of the elongate section such that rotation of the nut on the shaft adjusts a position of the shaft relative to the slot.

The term "threaded shaft" as used herein refers to a shaft having a thread extending between the ends thereof or a shaft having at least one threaded portion.

The upper portion of the side brace suitably comprises an elongate angular section which is preferably complementary in cross section to the support member.

Preferably, the upper portion of the side brace comprises an elongate substantially U- or V-shaped section.

Preferably, the connection between the side brace and the main post, and the connection between the support member and the main post, are adjustably movable along the main post.

10 Preferably, the main post, spreader bar, side brace and support member are all adjustable in length.

o:oo• Alternatively, the stabilising means may further include at least one counterweight attachable to the trestle at, or adjacent, a pair of 1 spreadable stiles on the opposite side of the trestle to the spreader bar to provide an additional stabilizing force.

Suitably, the at least one counterweight is attachable to a rung of the trestle adjacent the opposite pair of spreadable stiles.

a..

Preferably, the stabilising means comprises two counterweights for attachment to a pair of rungs located on opposite sides of the main post.

The at least one counterweight preferably comprises two spaced arms extending from an intermediate portion.

Suitably, two spaced arms taper in towards the intermediate portion.

In use, the intermediate portion may be located on a rung of the trestle such that the two arms extend towards a ground surface.

6 Suitably, the assembly further includes an adjustably extendable auxiliary leg attachable to a stile of the trestle.

Preferably, the auxiliary leg comprises an elongate hollow body in telescopic relationship with a ground engaging member.

Suitably, the elongate body comprises retaining clips engageable with the stile.

Suitably, the elongate body comprises a seat on which a ground-engaging portion of the stile is seatable thereon.

Preferably, the main post, in use, extends above the joint .10 connecting the spreadable stiles of the trestle, and the assembly further includes mounting means enabling side rails and/or end stop assemblies to be secured to the main post.

In another aspect, the invention provides a trestle fitted with i the stabilising assembly.

In yet another aspect of the invention, a pair of the trestles are provided with a handrail and/or end stop assembly including: 0:i ~one or more handrails connecting the main posts on the adjacent pair of trestles; and means for mounting the handrails on the main posts.

Preferably, an end stop is connectable transversely between the main post(s) on the opposite sides of the trestles and/or between the handrails extending along opposite sides of the plank(s) supported by the trestles.

BRIEF DESCRIPTION OF THE DRAWINGS To enable the invention to be fully understood, preferred A(Q embodiments will now be described described with reference to the accompanying drawings, in which: FIG. 1 is an isometric drawing of a trestle and plank assembly provided with a first embodiment of the stabilising assembly and a first embodiment of the handrail assembly; FIG. 2 is a similar view where the trestle and plank assembly is provided with a second embodiment of the stabilising assembly and a second embodiment of the handrail assembly; FIG. 3 is a side view of the main post and sectional views A-A, B-B and C-C thereof; FIG. 4 is a side view of the spreader bar fitted to the main post and legs of a trestle and is. sectional view A-A thereof; FIG. 5 is a side view of the spreader bar; e* e FIG. 6 is an end view of the first embodiment of the side brace and sectional views A-A, B-B and C-C thereof; 20 FIG. 7 is a side view of a leg grip for the side brace and sectional view A-A thereof; FIGS. 8 and 9 are similar views of the ~second embodiment of the side brace; FIG. 10 is an end view of the angle support; FIG. 11 is an isometric view of the first embodiment of the handrail system; FIG. 12 is a sectional end view of FIG. 11; FIG. 13 is an end view of the end stop bar; FIG. 14 is an isometric view of the second embodiment of the handrail assembly; FIG. 15 is a sectional end view taken on FIG. 14; FIG. 16 is an end view of a right-angle tie; FIG. 17 is an end view of the end stop bar; FIG. 18 is a perspective view of a third embodiment of the stabilising assembly and a third embodiment of the handrail assembly; FIG. 19 is a similar view where the trestle and plank assembly is provided with a fourth embodiment of the stabilising assembly and a fourth embodiment of the handrail assembly; FIG. 19 A shows a clamp assembly relating to the fourth embodiment of the hand rail assembly; FIG. 19B shows a cap of the third and fourth embodiment of the stabilising assembly; FIG. 19C shows a counterweight relating to the fourth embodiment of the stabilising assembly; and FIG. 20 shows the fourth embodiment of the stabilising assembly of FIG. 19 in more detail.

Goes OS6S e0 DETAILED DESCRIPTION *000.

15 With reference to the drawings, it will be understood that like reference numerals refer to like parts. Referring to FIG. 1, the trestle and plank assembly 10 has a pair of trestles 11, 12, supporting a plurality of planks 13 which are preferably clamped together using the clamp of our co-pending Patent Application No. 23614/97.

S Each trestle 11, 12 has a pair of ladder- .o like frames 14, 15 hingedly connected together at the tops of the frames. Frames 14, 15 have a plurality 25 of spaced horizontal rungs 16 connecting stiles 14A, 0 14B and stiles 15A, The trestle and plank assembly 10 is provided with a stabilising assembly 20 and the handrail assembly 60 to be hereinafter described in the similar manner to assembly Referring to FIG. 2, the trestle and plank assembly 110 has trestles 11, 12 and planks 13 provided with stabilising assemblies 120 and handrail assemblies 160 to be hereinafter described.

Referring to FIG. 3, the stabilising assemblies 20, 120 each have a main post 21 connected to stiles 14A, 15A of frames 11, 12 adjacent the hinge points between stiles 14A, 15A. As shown in sectional views B-B, C-C, the main post 21 is of a modified rolled hollow-section profile where the side walls are inwardly-stepped and a slot is provided in the outer face of the main post. (NB: The side brace and spreader bar are preferably of the same section profile.) Preferably, the relationship between the main post and the legs of the trestles is adjustable so that the main post 21 will engage the ground or floor when the trestles are erected, and the main post may be provided with ground-engaging feet (as shown in .00* eo 0FIG. 18 to be hereinafter described) Turning to FIGS. 4 and 5, a spreader bar 22 has a yoke slidably, lockably received in the main 15 post 21 for vertical adjustment and has its ends connected to stiles 14A, 15A of the trestle to maintain the angular relationship between the stiles of the trestle to make the trestle more rigid) o With reference to FIG. 6, a side brace 23 is shown having a yoke adjustably mountable in the main S"post 21, providing a hinged connection between the 0 0 "00 upper end of the side brace 23 and the main post 21, the lower end of the side brace 23 being provided with 0. a leg grip or foot 24 (see FIGS. 7 and As shown 0•0• 25 in FIG. 7, the side brace 23 is formed by two sections, telescopically-adjustable in length via a clamping assembly 25 shown in Section B-B. The clamping assemblies include a substantially C-section member and a locking plate interconnected by a nut and bolt assembly.

The angular relationship of the side brace 23 to the main post 21 is controlled by an angle support 26, 126 shown in more detail in FIGS. 5 and respectively. The angle support has a body 26A, 126A which telescopically receives a tongue member 26B, 126B connectable to the side brace 23. As shown in FIGS. 8 and Section C-C, the body 126A of the side support 126 may be mounted on a bracket 127 which, in turn, is mounted on a yoke 128 adjustably mountable on the main post 21.

It will be readily apparent to those skilled in the art that the side brace 23 extends in a plane substantially laterally to stiles 14A, 15A of the trestles, and by adjustment of the length of the side base 23 to ensure ground engagement by the feet 24 and fixing of the angle of inclination between the side brace 23 and the main post 21 stability of the trestle is ensured.

Referring to FIGS. 11 to 13, the handrail assembly 60 of the first embodiment has a pair of handrails 61, 62 extending parallel to, but spaced 15 above, one side of the planks 13 supported by the trestles 11, 12. A handrail clamp assembly 63 is mounted on the main post 21 and has a clamp 64 which enables the vertical position of the assembly 63 to be adjusted relative to the main post 21. The handrails 61, 62 are received in, and locked to, respective S"mounting sockets 65, 66 on the handrail clamp 64.

An end stop 67 has a mounting yoke 68 at each end, the yoke being engageable with, and releasably lockable to, the upper handrail 61.

In the handrail assembly 160 of the second embodiment shown in FIGS. 14 to 17, the handrail 161, 162 of adjacent plank sections are overlapped and secured together in the handrail clamp 163 on the main post 21. The end stop 167 is connected to the handrails 161 as hereinbefore described and a rightangle tie 169 (see FIG. 16) may be provided adjacent the free ends of the handrails 161, 162 to enable safety equipment, or other articles, to be secured thereto.

It will be readily apparent to those skilled in the art that the present invention provides respective stabilising and handrail assemblies for trestles and planks which markedly increase the safety of persons using the trestles and planks and where the main post is used as a base mounting unit for the stabilising and handrail assemblies on each side of the trestle.

The profile see FIG. 6, Sections B-B, C-C) employed to manufacture the main post, side brace and spreader bar enables sliding yokes or clamping members to be engaged therein for adjustable connection between the respective components.

Now turning to FIG. 18, there is shown a third embodiment of the stabilising assembly 220 and a third embodiment of the hand rail assembly 260. The fourth embodiment of the stabilising assembly 320 15 shown in FIGS. 19 and 20 is similar to the third embodiment of the stabilising assembly except for the use of counterweights 340 as described hereinafter.

The fourth embodiment of the handrail assembly shown in FIGS 19 and 20 is similar to the third embodiment of handrail assembly except for the use of overlapping rectangular section hand rails.

~The trestle and plank assemblies 210, 310 each have a stabilising assembly 220, 320 comprising a main post 21 connected to stiles 14A, 15A by way of cap 250, 350 seated on upper end portions 218, 318 of stiles 14A, 15A. As seen more clearly in FIG. 19B, cap 250, 350 is formed by an outer upright plate 251, 351 and an inverted U-shaped plate 252, 352. The cap 250, 350 is connected to main post 21 by cross member 253, 353.

A cross plate 255, 355 is located below cap 250, 350 and is bearingly engaged with upper portions of stiles 14A, 15A to impede torsion of the main post 21.

There is also included spreader bar 222, 322 which has a pair of clamping jaws 230, 330 at opposite ends of the bar 222, 322. The main post 21 is mounted to spreader bar 222, 322 by way of clamp assembly 280, 380 which is made up of V-shaped plate 281, 381 disposed within ring 282, 382 and clamp 283, 383 which is screw-threadedly engageable with an inner surface of the modified rectangular hollow profile forming the main post 21. The ring 282, 382 is connected to Ushaped plate 290, 390 which is slidably mounted on spreader bar 222, 322.

Another V-shaped plate 284, 384 is connected to plate 281, 381 and receives an upper end portion of a side brace 223, 323. Plate 284, 384 is set at an angle relative to plate 281, 381 to maintain a desired angle of inclination between the side brace 223, 323 and the main post 21.

15 Side brace 223, 323 is mountable on plate 284, 384 by clamp assembly 286, 386 operably connected to V-shaped plate 287, 387. Mounting is effected by placing a threaded shaft (not shown) of assembly 286, 386 into an angular slot 285, 385 of plate 284, 384 20 and clamping of the clamp.

V Side brace 223, 323 has a main hollow elongate body 223A 323A and a telescopically extendable leg 223B, 323B which is set to a desired position through clamp assembly 235, 335.

25 A counterweight system may be added. It can be used typically when the side brace 23, 123, 223, 323 is impractical such as when the trestle is mounted where the ground slopes away. Counterweights can be attached to the two inside stiles, on the side opposite the handrails. Ideally, the counterweights might be attached within one half metre of the ground.

Preferably, the counterweights are made of a metal such as iron and are constructed in the form of an inverted U shape. For example, reference may be made to the counterweight shown in FIGS. 19C and 20. The counterweight 340 has two arms 340A, 340B extending from an intermediate portion 340C. The arms 340A, 340B taper into the intermediate portion 340C. This tapering is advantageous because it affords a close fit between the counterweight and a rung 16 of a trestle when the counterweight 340 is placed on top of the rung 16 as shown. The close fit impedes lateral movement of the counterweight 340 along the rung 16 thereby maintaining the relative position of the counterweight 340 and maintaining the stability of the trestle.

Alternatively, the counterweight might be water in a suitable container, or other counterweights. Blocks of concrete may be convenient.

A bolt in the block provides an attachment to the counterweight. A cable and turnbuckle can be used to 15 connect to the trestle. The turnbuckle can be operated to take up slack in the attachment. The counterweights might be attached to a centre pull down point between the two inside legs. This is readily achieved by application of a spreader between them 20 with an attachment point midway along it.

With particular reference to FIG. 19, there is shown an adjustably extendable auxiliary leg 390 attachable to a stile (for instance) 14B of trestle 11, 12. The auxiliary leg 390 comprises an elongate 25 hollow body 391 in telescopic relationship with member 392 having a ground engaging foot 393. Body 391 comprises retaining clips 394, 395 engageable with stile 14B, as well as a seat 396 on which a foot 14C of stile 14B is seatable thereon. The length of member 392 is adjustable relative to body 391 by use of bolts extending through apertures 397 in body 391 and member 392 (not shown) In the handrail assemblies 260, 360 shown in FIGS. 18 to 20, the handrails 261, 262, 361, 362 of adjacent plank sections are overlapped and secured together in the handrail clamp generally shown at 263, 363 on the main post 21. Clamp 363 comprises an Eshaped profile permitting easy sliding of overlapping handrails 361, 363 therewithin. There is also provided retainer yoke 368 which is provided with a pin 369 for securing end portions of handrail 361, 362 in place.

The end stop 267, 367 is connected to main post 21 by locating the end portions 267A, 367A of the end stop 267, 367 in an upper channel of the main post 21 as shown.

The present invention has been described in terms of particular embodiments found or proposed by the present inventor to comprise preferred modes for the practice of the invention. Those of skill in the art will appreciate that, in light of the instant disclosure, various modifications and changes can be 15 made in the particular embodiments exemplified without departing from the scope of the invention. All such modifications and changes are intended to be included within the scope of the appended claims.

e* *e o* o.

Claims

2. The assembly of claim 1, wherein the stabilising means comprises a side brace, having a ground- engaging foot or feet, connectable to the main post and extendable substantially laterally of the plane 15 of spreading of the stiles.
3. The assembly of claim 2, wherein the side brace and the main post are interconnected by a support member to (optionally selectively) maintain an angular relationship between the main post and the 20 side brace.
4. The assembly of claim 3, wherein the support member comprises a mouth into which an upper portion of the side brace is engageable.
5. The assembly of claim 4, wherein the support member 25 comprises an elongate angular section.
6. The assembly of claim 5, wherein the mouth comprises an angular slot in a face of the angular section.
7. The assembly of claim 4, wherein the upper portion of the side brace comprises a compression means adapted to compress an outer surface of the support member to engage the side brace with the support member.
8. The assembly of claim 6, wherein the compression means comprises a clamp assembly including a threaded shaft and nut, the shaft being positionable within the slot, and the nut being 16 engageable with a surface of the elongate section such that rotation of the nut on the shaft adjusts a position of the shaft relative to the slot.
9. The assembly of claim 5, wherein the upper portion of the side brace comprises an elongate angular section which is preferably complementary in cross section to the support member. The assembly of claim 3, wherein the connection between the side brace and the main post, and the connection between the o support member and the main post, are adjustably movable along the main post. 0:900:
11. The assembly of claim 3, wherein the main post, spreader bar, side brace and support member are all adjustable in length. i 12. The assembly of claim 1, wherein the stabilising means further includes at least one counterweight attachable to the trestle at, or adjacent, a pair of spreadable stiles on the opposite side of the trestle S• to the spreader bar to provide an additional stabilising force.
13. The assembly of claim 12, wherein the at least one counterweight is attachable to a rung of the trestle adjacent the opposite pair of spreadable stiles.
14. The assembly of claim 12, wherein the stabilising means comprises two counterweights for attachment to a pair of rungs located on opposite sides of the main post. The assembly of claim 12, wherein the at least one /77 counterweight comprises two spaced arms extending from an intermediate position.
16. The assembly of claim 15, wherein the two spaced arms taper in towards the intermediate portion.
17. The assembly of claim 15, wherein the intermediate portion is locatable on a rung of the trestle such that the two arms extend towards a ground surface.
18. The assembly of claim 1, wherein the main post comprises a cap connectable to upper end portions of the spreadable stiles. coco
19. The assembly of claim 18, wherein the cap, in use, extends 10 below upper surfaces of the upper end portions except on an outer o• side of the stiles. The assembly of claim 18, wherein the main post comprises a cross member spaced below the cap and engageable with the oo° spreadable stiles.
21. The assembly of claim 1, wherein the spreader bar comprises compression means adapted to compress the outer surfaces of the spreadable stiles.
22. The assembly of claim 21, wherein the compression means comprises a pair of clamping jaws.
23. The assembly of claim 1 further including an adjustably extendable auxiliary leg attachable to a stile of the trestle.
24. The assembly of claim 23, wherein the auxiliary leg comprises i an elongate hollow body in telescopic relationship with a ground Cc engaging member. 18 The assembly of claim 24, wherein the elongate body comprises retaining clips engageable with the stile.
26. The assembly of claim 23, wherein the elongate body comprises a seat on which a ground-engaging portion of the stile is seatable thereon.
27. The assembly of claim 1, wherein the main post, in use, extends above the joint connecting the spreadable stiles of the trestle, and the assembly further includes mounting means enabling side rails and/or end stop assemblies to be secured to the main post. .:oo.i
28. A trestle fitted with the stabilising assembly according to any one of claims 1 to 26.
29. A pair of trestles according to claim 28, and further including a handrail and/or end stop assembly including: one or more handrails connecting the main posts on the 15 adjacent pair of trestles; and *oo• S• means for mounting the handrails on the main posts. The trestles of claim 29, wherein an end stop is connectable transversely between the main post(s) on the opposite sides of the trestles and/or between the handrails extending along opposite sides of the plank(s) supported by the trestles. DATED this fourteenth day of May 2001. PLANK MAGIC PTY LTD By its Patent Attorneys 1 FISHER ADAMS KELLY