IMP OVEMENTS IN AND RELATING TO SCAFFOLDING This invention is concerned with improvements in and relating to scaffolding and more particularly is concerned with planks for use therewith. Scaffolding comprising a plurality of up-right members arranged horizontally in spaced pairs. The upright members are connected together by elongate longitudinal members and elongate transverse members. The structure is suitably braced by diagonal members and is well understood in the art. - Planks are positioned on the transverse members at various levels and constitute work platforms to support workmen and materials at an elevated position adjacent to a structure on which work is to be performed.

In many cases the planks merely rest on the transverse members and are not interlocked therewith. In consequence there is a possibility that a plank or planks could move and in extreme cases become dislodged from its supporting scaffolding with a consequent risk of loss of life or injury to the workmen on it. In an attempt to overcome this problem scaffolding planks have been provided with hook members which extend from each end of the plank and hook over the transverse members. Whilst the use of such members has constituted an improvement of the provision of these members of each end of the plank necessitates the leaving of a space between end to end positioned planks. This has been found to be undesirable and in consequence there has been need in the trade to provide a scaffolding plank which can be positively interlocked with its supporting members and which is so constructed that adjacent

planks abut one another without leaving any appreciable space therebetween.

The invention comprises a plurality of upright members arranged horizontally in spaced pairs and connected together by - elongated longitudinal members and elongated transerve members to form a scaffolding structure; a scaffolding plank for use with such structure, said plank having at least one locating and retaining member extending downwardly from at least one end of each plank which is engagable with a channel member in or on Q said transverse member to correctly position and retain said planks on said transverse members.

Preferably means are provided to interlock the tongues in the respective channels.

Preferred embodiments of the invention will now be IS described with reference to the accompanying drawings in which:-

Fig. 1 is a perspective view of a typical scaffolding system with scaffolding planks supported thereon;

Fig. 2 is a cross-sectional side view of a scaffolding plank in 20 accordance with one form of the invention;

Fig. 3 is a cross-sectional view of a scaffolding plank in accordance with a further form of the invention;

Fig. 4 is a cross-sectional view of a scaffolding plank in accordance with a still further form of the invention;

25. Fig. 5 is a side view of a modified plank with its associated supporting transverse member;

Fig. 6 is a side view illustrating two planks supported on

the transverse member;

Fig. 7 is a view similar to Fig. 5 but showing a modification;

Fig. 8 is a side view of a modified structure suitable for use with die cast ends to the planks and also illustrates the associated supporting transverse member;

Fig. 9 is a side view of a structure suitable for use with a wood or plastic plank and also illustrates the associated supporting transverse member and an interlocking clip;

Fig. 10 is an inverted plan view of a plug member; and

Fig. 11 is a cross-sectional view of Fig. 10.

Referring now to the drawings the scaffolding comprises a plurality of up-right members 1 arranged horizontally in spaced pairs and connected together by elongate longitudinal members 2 and transverse members 3. The respective members are connected by clamps which are well known in the art and which do not form part of this invention. For this reason the clamps are not illustrated in the drawings.

Scaffolding planks 4 are supported on the scaffolding structure as illustrated. The planks are elongate members having parallel sides 5 and 6 parallel ends 7 and 8 with chamfered corners 9, 10, 11 and 12. The chamfered corners leave a square shaped opening 13 between adjacent end butted planks as illustrated in Fig. 1. The plank 4 may be formed of metal, wood or plastic material.

Fig. 2 illustrates a plank fabricated or moulded from mild

steel or aluminium and comprises a relatively thin load bearing surface 15 bent at right angles to form outwardly extending ends 16 and 17 which are bent to form stiffening channels 18 and 19 which are adapted to hook over the longitudinal members 2.

Fig. 3 illustrates a plank of hollow construction and is formed of aluminium in an extrusion operation. In this case the plank has two spaced parallel walls 20, 21 interconnected by web members 22, 23 and 24, the wall 20 extends downwardly at each end and connects with a wall 21 to form downwardly extending members 25, 26 which are adapted to hook over the longitudinal members 2.

Fig. 4 illustrates a plank constructed of wood or plastic. In this construction the bottom surface 27 may be rebated adjacent each side to provide seats 28, 29 to accommodate members, 30, 31 which are connected to the plank by screws 32, 33 and 34, 35. The members 30, 31 function in the same manner as the members 25 and 26 of Fig. 3.

Fig. 5 is a sectional end view of a plank and its - supporting transverse member and illustrates a modified structure which is suitable for a plank of folded steel or aluminium construction. It includes a channel member 36 having an inturned end 37 as illustrated in Fig. 5. A transverse member 3 is provided with a channel shaped transom member 38 which extends along the length of the member 3. The member 38 is substantially U-shaped having two up-standing limbs 40 and 41 and a bight portion 39, the free ends of the limbs are bent outwardly to form two load supporting flanges 42 and 43. The

limbs 40, 41 are provided with bores 44, 45 the purpose of which will be explained hereafter, and the centre portion of the bight portion 39 is bent upwardly to form a "V" shaped configuration so as to seat on a transverse member 3 to which

.5 is secured by welding as illustrated in Fig. 5.

In use the end 37 is entered into the transverse member 38 and is supported on the flange 43. The adjacent plank is also connected to the transom member 38 in the same manner and the dimensions are such that in this position there is minimal

Iff working space between the ends 7 and 8 of adjoining planks Fig. 6 illustrates two planks supported on the transom 38. Like parts have been given the same reference numerals and as will be apparent there is minimal working space between the end butted planks.

15 Fig. 7 shows the structure similar to that illustrated in Fig. 5. In the case of Fig. 7 transom member 38 is dispensed with. The transverse member 3 is formed of metal e.g. aluminium in an extrusion portion. The member 3 is provided with two integral spaced limbs 48, 49 the free ends of which are

20 turned outwardly to form two load supporting flanges 50, 51.

The limbs 48, 49 are provided with bores 52, 53, the purpose of which will be explained hereafter. As will be apparent the transverse member 3 of Fig. 7 functions in the same manner as the transverse member 3 and transom 38 of Fig. 5. ₍ 25 Fig 8 illustrates a structure suitable for use with die cast ends of the planks. The plank is formed of rectangular section tubes having top and bottom faces 54, 55. The open

ends of the tube accommodate plug members 56 only one of which is illustrated. The plug member is U-shaped having two parallel limbs 57, 58 connected by a web. The limb 57 is rebated so that when the plug is inserted in the plank the remaining surface of the limb 57 is a flush fit with the face 54. A limb 58 has two spaced parallel flanges 59 and 60 depending therefrom which define a transverse channel extending across the end of the plank. The flange 60 is shorter than the flange 59 which is provided with a bore 61 which is adapted to register with the bore in the transom member 38. The plank is secured to the transom in the same manner as described with reference to Fig.5.

Fig. 9 illustrates a structure suitable for use with a wood or moulded plastic plank and also illustrates the 55 associated supporting transverse member and a locking clip which also can be used in conjunction with the previously described embodiments.

The structure of the plank is identical with reference to Fig. 4 and the structure of the transverse member 3 and transom ^Q 38 is identical with reference to Fig. 6. In consequence like parts have been give the same reference numerals and no detailed description of these components is necessary. In this case the planks are retained against uplift in the transom by a spring clip member 62. 5 The member 62 is of substantial "U" shape having two limbs 63 and 64 connected by a web portion 65. The free ends of the limbs are bent inwardly as at 66 and 67. In use the clip is passed about the transverse member 3. The inturned ends 66 and

67 pass through the bores 52, 53 in the limbs 48, 49 and through the bore 46 in the members 30, 31. In this manner the abutting planks are positively locked to the transverse member 3. -.5 As indicated a square shaped opening 13 is left between adjacent end butted planks. In certain cases it is desirable that the opening be closed. This is effected by a plug 68 which has a tube portion 69 and a cover 70. The tube has four walls, 71, 72, 73 and 74 and a diagonal brace 75 connects 10 two opposite corners to give added strength to the tube. The tube is a sliding fit in the opening 13 and when positioned in this opening the cover 70 effectively shrouds the opening 13.