GB2362422A - Builders scaffolding - Google Patents

Abstract

The scaffolding is formed with a main run and a return run that are mutually inclined, preferably at right angles, with the main run including a plurality of spaced pairs of upright members 10a-j, ledgers 21 that connect the pairs together and with transoms 100 that connect the uprights of each pair. The return run has a decking unit which has first and second end parts, one of which co-operates with a ledger of the main run to support the respective end of the decking unit. The co-operating end part and the ledger are formed with inter-engaging and abutting surfaces that act to restrain relative angular movement between the two elements. Also disclosed is a ledger.

Description

2362422 1

Title: Improvements Relating to Builders' Scaffolding Description of Invention

This invention relates to a builders' scaffolding of the kind, hereinafter called scaffolding of the kind specified, which includes a main run and a return run which are mutually inclined, preferably at right angles, wherein the main run includes a plurality of spaced pairs of upright members, ledgers to connect the pairs together with the upright ineinbers of each paii. being connected together by a transom.

If desired adjacent transoms may support a decking unit or adjacent ledgers may support a decking unit.

An object of the invention is to provide a scaffolding of the kind specified wherein provision of a return run is facilitated.

According to a first aspect of the present invention we provide a builders' scaffolding of the kind specified wherein the return run has a decking unit which has first and second end parts one of which cooperates with a ledger of the main run to support oiie ciid of the decking unit.

The co-operating one end pail and the ledger inay restrain relative angular movement betweeti said one end pail and said ledger.

C.

Said ledger with which the decking unit co-operates inay have a side abutment surface and an upwardly facing abutinent surface and said one end pail may have abutment portions for en-agenient with said side abutment 0 0 surface and said upwardly facing abutinew surface at positions which are spaced lengthwise of the first said ledger.

The side abutment surface of the ledger inay be provided on a flange such that the side abutment surface is transverse to said upwardly facing abutment surface.

2 The end pails may be provided with a first projecting pail having an abutment portion to engage said upwardly facing abutment surface and a second projecting pail having an abutment portion to engage said side abutment surface.

The flange may be provided with a further side abutment surface on the opposite side of said flange to said side abutment surface.

Said side abutment surfaces may comprise a lip provided on the flange.

The abutment portion of the end pail may comprise a recess in which said flange is received.

Inner faces of said recess may be disposed to abut the side abutment surfaces.

The upwardly facing abutment surface may be provided on an upper transverse limb of the ledger.

The ledger may have a downwardly facing abutment surface disposed below said upwardly facing abutment surface.

Said downwardly facing abutment surface may be provided on said upper transverse limb.

The second projecting pail may be provided with a surface opposed to and spaced from the downwardly facing abutment surface of the upper transverse limb, The ledger may be provI'ded witli a lower ti--aiis,ei-se 11mb connected to said flange.

The lower transverse limb inay be connected to said upper transverse limb by a web pail.

The ledger may be provided with connectors fbi. connecting the ledger to the upright.

Each connector may be of genei.ally channel configuration in which upper and lower limbs provide the walls of the cliannel and a base for the channel being connected to end parts of a transverse member of the ledger.

The upper and lower limbs may be provided with apertures in which a wedge shaped member is received.

The decking unit may comprise a generally channel shaped member there being an in-turned lip at the free end of each linib of the channel.

The in-turned lip may have a re-entrant flange and the re-entrant flange may be generally parallel to and spaced fi-orn the firribs of the channel and the lip may be generally parallel to the base of the channel.

The angular movement may be ill a horizontal plane and/or in a vertical plane.

Each transom may comprise the same features as are set out in the preceding twenty paragraphs ill respect Of said ledger.

According to a second aspect of the invention we provide a ledger having at least one side abutment surface and n upwardly facing abutment surface and in which the or each side abutment surface faces ill a first direction.

At least one of the side abutment surfaces may be provided oil a flange of the ledger such that the at least one side abutment surface is transverse to said upwardly facing abutment surface.

The flange may be provided with a further side abutment surface oil the opposite side of said flange to said side abUtli-ient surface and hence facing ill a second direction opposite to said first direction.

Said side abutment surfaces may coniprise a turned over lip provided on the flange.

The upwardly facing, abutment Surface inay be provided oil all upper transverse limb.

The ledger may have a downwardly facing abLItIllCilt Surface disposed below said upwardly facing abutment surface.

Said downwardly facing abutment surface may be provided on said upper transverse limb.

4 The ledger inay be provided with a single lower transverse Iii-fib connected to said flange.

The lower transverse limbs may be connected to said upper transverse limb by a web pail.

The ledger may be provided with connectors for connecting the ledger to an upright.

Each connector may be of a generally channel configuration in which upper and lower limbs provide the walls of the channel and a base for the channel being connecting to end pails of a transverse member of the ledger.

The upper and lower limbs may be provided with apertures in which a wedge shaped member is received.

The invention will now. be described in inore detail by way of example with reference to the accompanying drawings wherem:- Figure 1 shows a pail of a builders' scaffolding according to the invention, Figure 2 is an exploded perspective view of pail of the builders' scaffolding of Figure 1, Figure 33 is a section on the line 33-33 of Figure 1, Figure 4 is a plan view of the builders' scaffolding of Figure 1 showing pail of a building, Figure 5 is a plan view of a return tl'a]ISOIII used in the pall of the scaffolding shown in Figure 4, Figure 6 is a side view of the return transom s.lio,ii in Figure 5, Figure 7 is an end view of the return transoni sliown in Figures 4 and 5, Figure 7a is an end view of an alternative configuration of the return transom of Figure 7, Figure 8 is a plan view of the builders' scaffolding of Figure 1 showing pail of a building.

Figure 1 of the accompanying drawings shows a scaffolding structure according to the invention comprising a plurality of upright scaffold members 10a - 101.

As can be seen frorn Figure 1 the upright saffold nienibers are arranged in pairs of spaced upright members, a first pair comprising the upright members 10a - 10b, a second pair comprising the upright members 10c and 10d and the members 10g and 10h positioned on top thereof, and a third pair comprising the upright members 10e and 1Of and the members JOi and 10j positioned on top thereof.

Each lowermost scaffold nieniber 10a - 1Og is provided at its lower end with an adjustable length jack 11. Each jack 11 coinprises an externally threaded tube 12 which is threadedly engaged with a nut 12Lt engaged with the bottom of the associated upright 1 Oa - 1 Of which fits o,el- the tube 12 above the nut 12a. The nut 12a is provided, in conventional inanner, with hand engageable portions 12b whereby it can be rotated to adjust the length of the jack. At the lower end each tube 12 is provided with a flat ground engaging plate 13. Since the orientation of the plates 13) relative to the axis of the upright does not matter there is no need to provide any ineans for rotation between the tube 12 and the plate 13), although stich may be pi-o\,lded if desired.

At their upper ends the lowerinost iipi-lgllt inembers 10, -]Of. are provided with a spigot 14 for engagenient in a socket, not showil, provided by the internal bore at the lower end of the upper upright nienibers 10g - 10j. It should be appreciated that if desired, further upright inen-ibers may be provided on top of the members 10a - 10b or on top of the ineinbers 10g -10j respectively and such stacking of uprights may be continued until the desired height for the scaffolding is achieved.

The uprights of each pair i.e. the uprights 10a and 10b; 10c, 10g and 10d 10h, and 10e, 10i and 10f, 10j, -are interconnected by cross rnenibers in the form of transoms 100. In use, the transonis provide cross-men-ibers which 6 extend substantially horizontally, substantially normal to the length of a wall or other structure adjacent the scaffolding.

An upright of each pair is interconnected by cross members in the form of ledgers 21 which, in use, provide cross-rnembers which extend substantially horizontally, substantially parallel to the length of the wall of other structure ad acent the scaffolding. Suitable ties as necessary are provided but the number required is less than has been hitherto required.

Each upright inember l0a - 10i is provded in known inanner with sockets 22 at spaced intervals along its length. Each socket 22 comprises a generally V-shaped strip of metal which is welded or otherwise secured to the exterior surface of the upright so as to define a socket which is open at both its upper and lower ends. Each socket 22 forms part of a connecting means which additionally comprises a connector, indicated generally -at 24, at opposite ends of each cross mernber 20 or 21 and a wedge shaped clamping member 25 which is captively associated with such connector. Four sockets 22 are provided at each of said spaced positions along the length of each upright, the sockets at each of said positions being equi-angularly spaced apart around the circumference of the upright. If desired, other forms of connecting means may be used. In the illustrated example all fOL11' sockets are at the same longitudinal position along the length of each upright bUt if desired one or more may be provided at different longitudinal positions.

Referring now to Figures 2 and 33, each transom 100 comprises a transverse member in the form of an elongate element 101, in the present example forined from cold rolled sheet metal, provided at each end with a connector 24.

Each end connector 24 is made as a pressing of generally channel section with a vertically disposed web 25 and upper and lower hinbs 26, 27 respectively. The upper limb 26 is formed with aq opening in the form of a slot 28 and the lower limb is formed with another opening also in the form of a slot 7 29, the two slots being of dimensions suitable for receiving an associated wedge clamping member 29. The length and disposition of each of the slots 28, 29 is selected in accordance with the angle between the wedging faces 3 1 a, 31b of the wedge clamping inember 29 and the disposition of abutment faces 32, 33 constituted by the fi.ec ends of the upper and lower limbs 26, 27 in relation to an internal clamping face 34 of the associated socket member 22 when the connector 24 is in use to secure a cross-inember to which it is secured to the upright inembei. 1 Oa - 1 Oj.

Referring now to Figure 3), the elongate element 101 comprises a transverse upper limb 102 spaced froin a pan. of generally co-plailar first and second transverse lower linibs 10-33, 104, connected thereto by a web pail 105. Extending generally upwardly fi-om the lower linibs 103), 104 are flanges 106, 107, the end pail of each of which is provided with an inwardly turned lip 108, 109. The transverse upper limb 102 provides an upwardly facing abutment surface 110a, whilst the downwardly facing surfaces of the transverse upper limb 102 provide second and third downwardly facing abuti-nent surfacess 1 10b5 1 1.0c. The end parts of the lips 108, 109 provide spaced first and second side abutment surfaces 111, 112. The outwardly facing, surfaces of the flanges 106, 107 provide third and fourth side abutment surfaces 11 114.

The transoms 100 support a plurality of decking units 40. As can be seen from Figure 1, in the present exaniple, three decking units 40 are disposed in side by side relationship between each pair of adjacent transoms 100 although in Figure 1 only some of the decking units are illustrated for clarity. It will be appreciated that, if desired, decking units rnay be provided which are of a different width to that described hereinbefore so that niore, or less, than three decking units may be provided associated with each pall. of tnansorns.

As best shown in Figures 2 and -3 3 each decliiig unit 40 is a rolled section of mild steel or other suitable inetal such as an aluniiniuni alloy and comprises an upper pail 41, a pair of spaced side linibs 42 depending downwardly 8 therefrom and having at the free end diereof I lips 4' which are generally parallel to the upper part 41 which may have at their free edges upturned flanges not shown which are generally parallel to the limbs 42. The upper part 41 has an upper surface 45 which, in use, supports operatives and equipment on the scaffolding structure and may be provided with any desired configuration of non-slip pattern or the like. Handles 40a in the form of bars welded to the inturned lips 43 to extend transversely of the decking unit may be provided at a suitable spacing to facilitate hatidlHig of a deckilIg unit 40.

Each decking unit 40 is of the saine coiifiguration and comprises longitudinally spaced first and second eiids 46, 47 respectively.

Each decking unit 40 is provided at each eiid 46, 47 with an end part 115. Each end pail 115 in the presetit example is formed from cold rolled sheet metal, and is affixed to the dechlll,), Ullit 40 by welding or by any other means as desired. Each end part 115 coniprises a first projectnig part 116 and a second projecting part 117 disposed spaced froin'and gerierally parallel to the first projecting part 116. The first projecting part 116 and the second projecting part 117 are connected by a web 118 depending froin the projecting pail 116. The second projectiiig pail 117 coinprises a coiinecting pail 119 which extends in a directiori geiierall, imvai-dly of the deckilig unit 40, the connecting pail 119 being shaped to defiiie a recess 120. The web 118 in the present example is shaped at Its lower part pirtly to accommodate tile connecting part 119 and the recess 120.

In use, the end parts 115 are eii,(,aged witli the eloiigate member 101 as best shown in Figure 33. A lower SUrface 116a of the first projecting part 116 rests on the upwardly facing abutniew surface I I Oa of tile transverse upper limb 102. Tile flanges 106, 107 are received in the respective recess 120 of tile end pails 115, such that the first side abLitinent surfike I I I and tile second side abutment surface 112 contact a first iiiiiet- face 120a of tile respective recess 120, while the third and fourth side abutmem sLirfaces 11-3), 114 are disposed 9 facing and spaced froin a second inner face 120b of the recess 120. 111 tins position, the load of the decking unit 40 is transmitted through the first projecting element 116 and the transverse upper limb 102. The engagement of the side abutment surface 111, 112 with the first inner face 120a of the recess 120 prevents disengagement of the decking unit 40 from the transom 100 in a direction transverse to the transom 100.

The engagement of the first projecting element 116 with the upwardly facing abutment surface 1 10a, and the flanges 106, 107 in the respective recess 120 acts to restrain angular rnoveinent of the decking unit 40 relative to the transom 100 in a vertical plane. Angular rnoverne nt of the decking unit 40 in a plane containing the decking unit, lierein referred to as a liorizontal plane, will be resisted by the flanges 106, 107 received in the respective recess 120 engaging the respective first and second inner faces 120a, 120b of the recess 120 as the decking unit rotates.

Referring to the left hand decking unit 40 as seen in Figure -3), rotation of the decking unit 40 in a generally clockwise direction as seen in Figure 7 will be limited by engagement of the first projecting pail 116 and the upwardly facing abutment surface 1 10a, and of the first side abutnient surface 111 with the first inner face 120a of the recess 120a. Rotation in a generally anticlockwise direction is similarly lirnited as a result of second inner fac e 120b of the recess 120 being brouglit into contcact witli the tliii.d side abutment surface 113 of the flange 106.

Angular movement of the left liand decking unit 40 in a horizontal plane limited by engagement at one end tliereof between the surfaces 111 and 120a and at the other end thereof between the surfaces 11 -3) and 120b.

Similar limitation of angular movement in a vertical plane and a horizontal plane takes place for the nglit hand decking unit 40.

In the present example, the gal) between the tlili.d and fourtli side abutment surfaces 1133, 114 and the first and second inner faces 120a, 120b of the respective recess 120 is 21nin, sufficient to perinit engagement of the end pail 115 with the elongate element 110 whilst resisting substantial angular movement in a horizontal plane.

Each decking unit 40 may be assembled to a pair of spaced transoms by offering up a decking unit 40 in an inclined position so that the free end of the element 116 of the pail 115 at one end of the decking unit 40 is engaged with the web 105 of a transom 100. The free end of the second projecting pail 117 at the other end of the decking unit can then move past the fi-ee end of the upper transverse end 102 of the adjacent transom so that after inovernent of the decking unit to space the element 116 fl.oiii the web 105 the end pails 115 at each end of the decking unit can be positioned as shown in Figure 3. Either end of the transom may be first engaged with its associated transorn. Removal of a decking unit is the reverse of the assenibly arrangement described above.

Because of the above described restrain of angular movement in a horizontal plane, each decking unit effectively acts to foiiii a diaphragm and so the requirement for tie menibers is reduced.

Should the decking unit 40 be lifted as a wliole generally veilically, or rotated so only one end is lifted, for example, tlirough wind lift, an upper surface 11 7a of the second projecting pail 117 will be brought into contact with the downwardly facing abutinent surface 11 OD, 11 Op of the transverse upper limb 102, restraining any furtlier upward iiio\, eiiieiit of the end pail 115 and preventing disengagement of the deckiii, (.,, unit 40 fl.om the elongate element 101. When the upward force on the decking unit 40 decreases, for example when the wind drops, the decking unit 40 will fall, re-engaging the recess 120 CI with the flange 106, 107.

Upward pivoting of only one end may be Ilinited or resisted either by the above described contact alone or by the above described Ilinitation of rotation in a vertical plane or by a desired eoiiibiiiitioti tliereof.

11 Although in the present example, a lower surface 11 7b of the second projecting part 117 is shown spaced from an upwardly facing surface 103a, 104a of the transverse lower hirib 10-3), 104, the end parts 115 can be disposed such that the lower surface 117b contacts the upwardly facing surface 10-3a, 104a, and indeed if desired the load of the decking unit 40 could be transmitted partly or wholly through the second projecting pail 117 in preference to the first projecting part 116.

The flanges 105, 106 and the recesses 120 may alternatively be disposed such that the third and fourth side abutinent surfaces 11-3), 114 contact the second inner faces 120b of the recesses 120 and the first and second side abutment surfaces 111, 112 are spaced fi.oiii the first inner faces 120a of the recess 120, preferably by a gap of 21-nin. Further alternatively the flanges 105, 106 may be spaced fi-om all faces of the recesses 120 In the latter case, for example the first and second side abutment surfaces 111, 112 rnay be spaced from the first inner faces 120a by I inin and the thIrd and fourth side abutment surfaces 113, 114 may be spaced froin the second iiiner faces 120b also by Imm.

In the present exarnple each bay i.e. element structure defined by four orthogonally disposed uprights is 10Ocin wide and Lip to 30Ocin long. Each decking unit, in the present exaniple about 32cin wide up to 30Ocin long but, if desired, both the bays and the decking, units ina ' be of other configuration to n Y that described liereinbefore.

Although in the above examples for ease ofinanufacture the coillpollents have cooperating surfaces which are continuous and planar, if desired, one or more of the cooperating surfaces could be continuous and provided with localised projecting areas, or could be provided oi spaced separate elements, so as to be spaced an appropriate distance apart leii,,,tli,ise of the transom for C cooperation with a continuous planar or sinillar localised areas of the 12 cooperating surface, or with spaced separate eleinents to provide the hereinbefore described connection and restraint from angular movement.

In order to provide adequate restraint of relative angular movement, the cooperating surfaces are preferably laterally spaced by a distance of at least 10CM. If desired, the spacing may be less than or greater than 10cm, the spacing depending upon the extent of restraint to relative angular movement required in any particular structure.

In both embodin-ients, the ledgers 21 each have a single elongate element which is a solid bar of a desired square configui-ation in cross-section but, if desired, may be of tubular construction and/or of other than square configuration in cross-section. A connector is connected, by welding in the present example, to each end of the elongate elenient.

Alternatively, the ledgers may be of the sanie configuration as the transoms of the embodiments described herein and the decking units may have end pails as described liereinbefore but engaged with the ledgers. In this case the decking units extend at 90' to the direction illustrated in connection with the first embodiment.

If desired, the transonis of the alternative inay be the same as the transoms described in connection with the einbodinients described liereinbefore or may be of the configuration described above in relation to the ledgers of the ernbodiments liereinbefore or indeed may be of any other suitable design configuration.

When the transoms of the alternative are of the saine configuration as the transoms of the en-ibodunents described hereinbefore the adjacent decking units may have an adjacent part of the sanie or sinillai. configuration to the end pails engaged with the ledgers so as to engage with the transoni in the same or a similar way as the end parts engage with the ledgers.

The connectors described liereinbefore in connection with the transom are the same as the con-nectors provided on the ledgers and therefore do not require further discussion.

Referring now to Figures 4 to 8. There is sliown at 190 a main run of the scaffolding which is the part of the scaffolding shown 190 in Figure 1 but drawn to an enlarged scale and which constitutes a main run of the scaffolding. The main run 190 is arranged to extend parallel to a wall of a building or the like.

Mutually inclined, in the present example, at right angles to the main run 190 is a return run 195. The uprights 1 Oa - 1 Od are of the same construction as described previously in connection witli Figures 1 to 33. The transoms 100 are as described in connection with Figures 1 to -33 as are the decking units 40. The ledgers, in the present example, ledger 200 which are connected to the uprights in the same manner as the transoms 100. In the present example each of the two transoms 200, referred to at 21 in Figtire 1, comprises a longitudinally extending member in the form of an eloiigate elenietit 20 1, in the present example formed from cold rolled sliect inetal, provided at eacli end with a connecting element 24 which as it is the sanie as the contlecting element 24 described liereinbefore in connection witli the transonis 100, the same reference numeral has been used and ftirtlier descriptioti is not reqUired.

The elongate element 201 comprises a transverse upper Illilb 202 spaced from a transverse lower linib 203 and coiniected tliereto by a first web part 203a. At its other end extending geiiei.all/ Upwardly fi-oiii the lower first limb pail 20-3) is part 20-33b which is integral witli the ftirtlier transverse lower limb 204 which is connected to the upper limb 202 by a web part 205. Extending generally upwardly from the lower 11mb 204 is a flange 207 the end part of which is provided with an intunied lip 209. The transverse upper 11111b 202 provides an upwardly facing. abtitnient stirface 210a wlillst the downwardly facing surfaces of the traiisverse tipper Ilinb 202 provide a downwardly facing 0 14 abutment surface 210c. The end part of the lip 209 provides a side abutment surface 212. The outwardly facing surface of the flange 207 provides a further side abutment surface 214.

The return run 195 comprises a plurality, in the present example, three, of decking units 240 of lll<e configuration to the decking units 40 described with reference to Figures 1 to J3). In use, one end part 115 'Is engaged with the ledger 200 in exactly the same man-ner as described hereinbefore with reference to Figure 3. In particular a lower surface 116a of the first projecting part 116 rests on the upwardly facing abutment surface 210a of the transverse upper limb 202. The flange 207 is received in a recess 120 of the end pail 115, such that the side abutirient siii-face 2 12 coiitacts a first inner face 120a of the recess 120, whilst the side abutment SUrface 214 is disposed facing and spaced fi-om a 0 second inner face 120b of the recess 120. 111 this position, the load of the decking unit 40 is transmitted througli the first projecting element 116 and the tranverse upper limb 202. The engagenient of the side abutment surface 112 with the first inner face 120a of the recess 120 prevents disengagement of the decking unit 40 from the ledger 200 In a direction transverse to the ledger 200.

The engagement of the first pi. 'ectii(, eleirient 116 with the upwardly CJ 1 11 facing abutment surface 210-a and the fianpoe 207 in the recess 120 serves to CD restrain angular movement of llie tnilit 40 relative to the ledger in a vertical plane. Angular moven-iew of the decking i.iiiit 40 ill a plane containing the decking unit, hereinafter referred to as a lioi-j.oiital plane is resisted by the flange 207 received in the recess 120 the first atid second inner faces C1 Z _ C1 120a and 120b of the recess 120 as the deekiii,(.,, iinit rotates in a sullilar manner to that described above witli regard to rotatioii of the decling unit relative to a transom in connection witli FigUre 7.

In the present example, the gap between the side abutilient surfaces 114 and the inner faces 120a, 120b of the recess 120 is 2 mill, stifficient to permit engagement of the end pail 115 witli the ledger 200 whilst resisting substantial angular movement in a horizontal plane.

The other end of the decking unit is engaged with a transorn 100a of the return unit which is the same as the transom 100 of the main unit. Thus each decking unit of the return unit may be assembled to a ledger 200 and to a transom of the return unit by offering up a decking unit 240 in an inclined position so that the free end of the element 116 of the pail 115 and the end of the decking unit 240 is engaged witli the web 205 of the ledger 200 or the web 105 of the transom 100. Thereafter connection Is as described in connection with the decking unit 40 associated with adjacent transonis 110 illustrated in Figures 1 to 3. In all other respects the decking unit 240 operates as described hereinbefore in connection witli the decking units 40 of the second embodiment.

If desired, the ledger 200 may be of a welded two-part construction as shown in Figure 7a where the same reference nunierals liave been used as were used in Figure 7 and its mode of use is as described lierein with reference to Figure 7. If desired instead of the le(l,,:,,ei.s 200 described hereinbefore with

regard to Figures 4 to 8 the ledgers inay liave the "b,,icl-to-back" COI)f-lgLilc-,1t1011 Of tlIC transoms described hereinbefore witli regard to Figures 1 to 3) and in this case C) relatively short decking units may be provided for the inain unit extending between and supported by sucli ledgers.

The features disclosed in the foregoing description, or the following claims, or the acconipanyIng drawings, expressed in tbeir specific forms or in terms of a ineans for perforining the disclosed function, or a inetliod or process for attaining the disclosed result, as appropriate, inay, separately, or in any combination of such features, be utilised for realising the invention in diverse

C forms thereof 16

Claims (1)

1. A builders' scaffolding of the kind specified wherein the return run has a decking unit which has first and second end parts one of which cooperates with a ledger of the inain run to support one end of the decl<liig unit.

2. A builders' scaffolding accoi-diii,(,,, to Claup 1 whereiri the cooperating one end pail and the ledger restrain relative angular movement between said one end pail and said ledger.

3. A builders' scaffolding according, to Claiiii 1 or Clalin 2 wherein said ledger with which the decking unit co-operates has a side abutment surface and an upwardly facing abutment surface and said one end pail has abutment portions for engagement with said side abianiew surface aild said upwardly facing abutment surface at positioiis which are spaced leil, (,,tliwise of the first said ledger.

4. A builders' scaffolding accordnig to Claiin 33 wherein the side abutment surface of the ledger is provided oii a flange sucli that the side abutment surface is transverse to said upwardly facijig abutinew siii-ftce.

5. A builders' scaffolding according to Clann 3) or Clann 4 wherein the end pails are provided with a first projecting part haviiig an abittnient portion to engage said upwardly facHig abiitiiieiit surface aiicl a secoii(l projecting pail having an abutment portion to engage said side abLitinent surface.

6. A builders' scaffolding according to aiiy oiie of Claims 4 or 5 when dependent on Claim 4 wherein the flajige is provided \vIth a further side 17 abutment surface on the opposite side of said flange to said side abutment surface.

7. A builders' scaffolding according to Claim 6 wherein said side abutment surfaces comprises a lip provided on the flange.

Z 8. A builders' scaffolding according to Claim 7 wherein the abutment portion of the end pail comprises a recess iii which said flange is received.

9. A builders' scaffolding according to Clalin 8 wherein Inner faces of said recess are disposed to abut the side abutinew surfaces.

10. A builders' scaffolding according to aiiy one of Clanns -3 to 9 wherein the upwardly facing abutment surface is provided on ari upper transverse limb of the ledger.

11. A builders' scaffolding according to Claim 10 wherein the ledger has a C) downwardly facing abutinew surface disposed below said upwardly facing abutment surface.

12. A builders' scaffoldiii,,,, accordnig to Claun 11 x,,liei.ciii said downwardly facing abutment surface is provided oii said upper traiisverse Ilinb.

13. A builders' scaffolding according to Claun 5 or any one of Clailils 6 to 13 when dependent on Claini 5 wherciii the second pi-Qlectiiig pail is provided with a surface opposed to aiid spaced froin the downwardly facillg abutment surface of the upper transverse 11mb.

18 A builders' scaffoldiiig accordiiig to Claiin 4 or any oiie of Clairns 5 to 13 when dependent on Claim 4 wherein the ledger is provided with a lower transverse limb connected to said flange.

15. A builders' scaffolding according to Claim 14 when dependent on Claim 10 or any one of Claims 11 to 13) when dependerit on Clain] 10 wherein the lower transverse limb is connected to said upper ti aiisverse limb by a web pail.

16. A builders' scaffolding accordiiig to aiiy oiie of the precediiig claims wherein the ledger is provided with coiniectors for connectiiig the ledger to an upright.

17. A builders' seaffoldiii,(,, accoi-diii,,,,, to Clairn 16 wliei-eiii each connector is of generally channel configuratioii M wlilcli upper and lower limbs provide the walls of the channel and a base for the cliainiel beiiig connected to end pails of a transverse member of the ledger.

C 18. A builders' scaffolding accordiiig to Clann 17 wlierein the upper and lower limbs are provided witli apertures in whicli a wedge sliaped illeilibei. is received.

19. A builders' seaffoldiiig accoi.diii,(:), to any oiie of the preceding clanns D wherein the decking uiiit coinprises a geiiei-ally clialmel sliaped ineinber tliere being an in-turned lip at the free eiid of each llnib of the chaimel.

20. A builders' scaffolding accoi-diii,, to Claiiii 19 wherciii the iiiturlied lip C has a re-entrant flange wid the i-e-eiiti.aiit flaii.ge is generally parallel to and spaced from the limbs of the cliaimel aiid the lip is geiiei.ally parallel to the base of the channel.

19 21. A builders' scaffolding according to Claim 2 or any one of Claims 3 to 20 when dependent on Clairn 2 wliei.eiii the angular inovement is in a horizontal plane and/or in a vertical plane.

22. A builders' scaffolding according to any one of the preceding claims wherein each transom comprises the saine features as are set out in the preceding twenty paragraphs in respect of said ledger.

23. A builders' scaffolding substantially as liereinbefore described with reference to the accompanying drawnigs.

24. A ledger having at least one side abutment surface and an upwardly facing abutment surface and in wIiicl, the or eacli side abiament surface faces in a first direction.

25. A ledger according to Claim 24 wliei.ciii at least one of the side abutment surfaces is provided on a flange of the ledger sucli that the at least one side abutment surface is transverse to said upwardly facing abutment surface.

26. A ledger according to Claim 25 wliei-ciii the flange is provided witli a further side abutment surface on the opposite side of said flange to said side abutinent surface and hence facing in a second direction opposite to said first direction.

27. A ledger according to Claim 26 x,liei-ciii said side abutment surfaces comprise a turned over lip of the flange.

C> 28. A ledger according to any one of Clanyis 24 to 27 wherein the upwardly facing abutment surface is provided on an upper transverse Ilinb.

29. A ledger according to Claim 28 wherein the ledger has a downwardly facing abutment surface disposed below said upwardly facing abutment surface.

30. A ledger according to Claim 29 wherem said downwardly facing abutment surface is provided on said upper transverse litrib.

31. A ledger according to Claim 25 or any one of Claims 26 to 30 when dependent on Clairn 25 wherein the ledger is provided with a single lower transverse limb connected to said flange.

Z-71 32. A ledger according to Claim 33l whereiii the lower transverse limb is connected to said upper transverse limb by a web part.

33. A ledger according to any one of Clainis 24 to 32 wherein the ledger provided with connectors for connecting the ledger to aii upright.

b is 34. A ledger accordiing to Claini 333) wherein each comiector is of a generally channel configuration in which upper and lower hinbs provide the walls of the channel and a base for the channel being connecting to end parts of a transverse member of the ledger.

35. A ledger according to Claim 34 wherein the upper and lower limbs are provided with apeilures in which a shaped member is received.

21 36. A ledger substantially as lici-ciiibefoi-e described with reference to the accompanying drawings.

37. Any novel feature or novel combination of features described hereiri and/or in the accompanying drawings.