GB1592159A

GB1592159A - Scaffolding joint

Info

Publication number: GB1592159A
Application number: GB47822/76A
Authority: GB
Original assignee: Rapid Metal Developments Ltd
Current assignee: Rapid Metal Developments Ltd
Priority date: 1976-11-17
Filing date: 1976-11-17
Publication date: 1981-07-01
Also published as: AU511591B2; IE45836L; NZ185701A; FR2371560A1; AU3062077A; FR2371560B3; ZA776654B; IE45836B1

Description

(54) SCAFFOLDING JOINT (71) We, RAPID METAL DEVELoP- MENTS LIMITED, a British Company of Stubbers Green Road, Aldridge, Walsall, Staffordshire WS9 8BW, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to a scaffolding joint and to a method of making such a joint. The invention also embraces scaffolding incorporating the aforesaid joint.

According to the invention, a scaffolding joint comprises a lug for securing to one of a pair of scaffolding members to be connected together, the lug having a portion adapted to be secured to the outer surface of said one member so as to project outwardly of that surface and extend substantially longitudinally of said one member and a pair of flanges projecting transversely of said portion to provide a pair of substantially planar surfaces facing the outer surface of said one member when said portion is secured to the latter, and a bracket for securing to the other member and being shaped to embrace the lug, in use, so that surfaces on the bracket engage respectively said pair of flange surfaces of the lug, at least one of said lug flanges being upset to form a localised protuberance projecting outwardly of the outer surface of said member when the lug is secured to the latter, and locking means associated with said bracket such that, with the bracket assembled on the lug, the locking means may be brought into engagement with the protuberance to lock the bracket and lug together.

Preferably, the lug is generally of T-section, the lower end portion of the stem of the T being removed and the thereby freed end portion of the cross-bar of the T being bent towards said one member, and preferably into engagement with the end of- the stem to form supporting abutments for the bracket.

From another aspect of the invention, a method of making a scaffolding joint includes the steps of subjecting T-section material to a shearing operation to remove an end portion of the stem of the T and thus leave a projecting portion of the bar of the T, deforming the projecting portion of the bar into abutment with the adjacent end of the stem, and simultaneously or subsequently upsetting the bar of the T in a direction generally away from the stem on at least one side thereof to form a protuberance.

The invention will now be described, by way of example, with reference to the accompanying drawings in which: Figure 1 is a perspective view of a scaffolding joint of the invention in disassembled condition, Figure 2 is a plan view of the joint of Figure 1, when assembled, and Figures 3A to 3D show various stages in the manufacture of a lug forming part of the joint of Figures 1 and 2.

Referring to Figures 1 and 2 of the drawings, these show a first scaffolding member in the form of a scaffolding tube 1 having four identical lugs 2 secured thereto at 90" intervals. Each lug is generally T-shaped in cross-section with the stem 3 of the T secured to the tube, the bar 4 of the T forming lateral flanges 5. The stem 3 of the T is foreshortened at its lower end and the unsupported end portion of the bar 4 is bent inwardly until perpendicular to the bar to form a pair of support surfaces 6, one at either side of the stem 3. The inwardly bent portion of the bar is secured to the tube 1.

The bar 4 of the T is formed with a pair of localised outwardly projecting protuberances 7 for the purpose to be described.

The other portion of the scaffold joint of the invention, conveniently formed by a rolling - operation, is a generally U-shaped bracket 8, the base 9 of which is secured, as by welding for example, to a further scaffold member in the form of a tube 10 which will be arranged horizontally in use. The arms 11, 12 of the U have inwardly bent portions designated respectively 13 and 14, the dimensions of and spacing between which are chosen to permit the bracket 8 to be assembled onto a lug 2 with the stem 3 of the lug between the portions 13 and 14 of the bracket and with the inner surfaces of those portions engaging the lug flanges as can be seen more clearly from Figure 2. The bracket is supported in a vertical direction by engagement of the portions 13 and 14 thereof against the support surfaces 6 of the lugs.

A locking device is provided in the form of a threaded bolt 15 extending through the arm 12 of the bracket and into threaded engagement with a threaded aperture in the arm 11. The bolt includes a boss 16 by which it is rotatably supported in the aperture of the arm 12 and has the alternative facility of a hexagonal portion 17 and a rectangular hole 18 permitting turning respectively by means of a spanner and tommy-bar.

The boss 16 has a bevelled end portion 19 which, in the assembled condition of the joint shown in Figure 2, comes into abutment with one of the protuberances 7. A resultant force is produced acting in the direction of arrow F (Figure 2) urging the portions 13 and 14 of the bracket securely against the flanges 5 to lock the joint in its assembled condition.

It will be appreciated that only one protuberance 7 is strictly necessary for the proper functioning of the joint of the invention, the other protuberance being produced as a matter of manufacturing convenience.

It has been found to be particularly convenient to manufacture the lug 2 from Tsection stock material, bv subjecting the material to a first shearing operation which simultaneously tapers the stem 3 in a lengthwise direction and removes a portion thereof to produce the shape shown in Figure 3A, from which it will be seen that a portion 4a of the bar 4 extends beyond the end 3a of the foreshortened stem. The original shape of the stem 3 is indicated in broken lines. In a next stage of the process, a portion 4a is bent into abutment with the end 3a of the stem. Simultaneously or subsequently, an upsetting operation is performed on the bar 4 to produce the protuberances 7, one in either flange 5. A final coining operation flattens the outer extremities of the protuberances 7 at 7a to provide extra thickness and strength.The lug so formed is welded into position on the scaffold member 1 and the bar 4 is inclined to the member 1 by virtue of the taper of the stem 3, typically at 5 , to provide a wedging action with the bracket, the inner surfaces of the bracket portions 13 and 14 being similarly inclined.

The method outlined above of forming the lugs has been found to be very economical as compared with conventional methods of making lugs for scaffolding joints.

It will be appreciated that the shape and form of the bracket 8 and locking device 15 can be varied as desired, consistent with the requirement that these components perform the function described above.

The member 1, although shown with four lugs may have any convenient, usually even, number of lugs.

WHAT WE CLAIM IS:- 1. A scaffolding joint comprising a lug for securing to one of a pair of scaffolding members to be connected together, the lug having a portion adapted to be secured to the outer surface of said one member so as to project outwardly of that surface and extend substantially longitudinally of said one member and a pair of flanges projecting transversely of said portion to provide a pair of substantially planar surfaces facing the outer surface of said one member'when said portion is secured to the latter and a bracket for securing to the other member and being shaped to embrace the lug, in use, so that surfaces on the bracket engage respectively said pair of flange surfaces of the lug, at least one of said lug flanges being upset to form a localised protuberance projecting outwardly of the outer surface of said member when the lug is secured to the latter, and locking means associated with said bracket such that, with the bracket assembled on the lug, the locking means may be brought into engagement with the protuberance to lock the bracket and lug together.

2. A joint according to Claim 1 wherein the lug is generally of T-section with the stem of the T extending longitudinally of and secured to said one member and the cross-bar of the T forming the flanges.

3. A joint according to Claim 2 wherein the lower end portion of the stem of the T is removed and the thereby freed end portion of the cross-bar of the T being bent towards said one member to form supporting abutments for the bracket.

4. A joint according to Claim 3 wherein said freed end portion of the cross-bar is bent into engagement with the end of the stem to form supporting abutments for the bracket.

5. A joint according to any one of the preceding claims wherein similar protuberances are formed respectively on the flange.

6. A joint according to ;any one of the preceding claims wherein the or each protuberance is curved in a direction generally away from the outer surface of said one member.

7. A joint according to any one of the preceding claims wherein the outermost surface of the or each protuberance has a flattened portion.

8. A joint- according to any one of the

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. the dimensions of and spacing between which are chosen to permit the bracket 8 to be assembled onto a lug 2 with the stem 3 of the lug between the portions 13 and 14 of the bracket and with the inner surfaces of those portions engaging the lug flanges as can be seen more clearly from Figure 2. The bracket is supported in a vertical direction by engagement of the portions 13 and 14 thereof against the support surfaces 6 of the lugs. A locking device is provided in the form of a threaded bolt 15 extending through the arm 12 of the bracket and into threaded engagement with a threaded aperture in the arm 11. The bolt includes a boss 16 by which it is rotatably supported in the aperture of the arm 12 and has the alternative facility of a hexagonal portion 17 and a rectangular hole 18 permitting turning respectively by means of a spanner and tommy-bar. The boss 16 has a bevelled end portion 19 which, in the assembled condition of the joint shown in Figure 2, comes into abutment with one of the protuberances 7. A resultant force is produced acting in the direction of arrow F (Figure 2) urging the portions 13 and 14 of the bracket securely against the flanges 5 to lock the joint in its assembled condition. It will be appreciated that only one protuberance 7 is strictly necessary for the proper functioning of the joint of the invention, the other protuberance being produced as a matter of manufacturing convenience. It has been found to be particularly convenient to manufacture the lug 2 from Tsection stock material, bv subjecting the material to a first shearing operation which simultaneously tapers the stem 3 in a lengthwise direction and removes a portion thereof to produce the shape shown in Figure 3A, from which it will be seen that a portion 4a of the bar 4 extends beyond the end 3a of the foreshortened stem. The original shape of the stem 3 is indicated in broken lines. In a next stage of the process, a portion 4a is bent into abutment with the end 3a of the stem. Simultaneously or subsequently, an upsetting operation is performed on the bar 4 to produce the protuberances 7, one in either flange 5. A final coining operation flattens the outer extremities of the protuberances 7 at 7a to provide extra thickness and strength.The lug so formed is welded into position on the scaffold member 1 and the bar 4 is inclined to the member 1 by virtue of the taper of the stem 3, typically at 5 , to provide a wedging action with the bracket, the inner surfaces of the bracket portions 13 and 14 being similarly inclined. The method outlined above of forming the lugs has been found to be very economical as compared with conventional methods of making lugs for scaffolding joints. It will be appreciated that the shape and form of the bracket 8 and locking device 15 can be varied as desired, consistent with the requirement that these components perform the function described above. The member 1, although shown with four lugs may have any convenient, usually even, number of lugs. WHAT WE CLAIM IS:-

1. A scaffolding joint comprising a lug for securing to one of a pair of scaffolding members to be connected together, the lug having a portion adapted to be secured to the outer surface of said one member so as to project outwardly of that surface and extend substantially longitudinally of said one member and a pair of flanges projecting transversely of said portion to provide a pair of substantially planar surfaces facing the outer surface of said one member'when said portion is secured to the latter and a bracket for securing to the other member and being shaped to embrace the lug, in use, so that surfaces on the bracket engage respectively said pair of flange surfaces of the lug, at least one of said lug flanges being upset to form a localised protuberance projecting outwardly of the outer surface of said member when the lug is secured to the latter, and locking means associated with said bracket such that, with the bracket assembled on the lug, the locking means may be brought into engagement with the protuberance to lock the bracket and lug together.

8. A joint- according to any one of the

preceding claims, wherein the locking means includes a screw device engaged in a screw threaded aperture in the bracket and having a boss for engagement with one of the protuberances.

9. A joint according to Claim 8 wherein the boss of the screw device has a bevelled surface for engagement with the said one of the protuberances.

10. A joint according to Claim 8 or Claim 9, wherein the screw means acts transversely of said one member.

11. A joint according to any one of the preceding claims wherein the lug and bracket are secured respectively to said scaffolding members.

12. A scaffolding joint as hereinbefore described with reference to Figures 1 and 2 of the accompanying drawings.

13. A method of making a lug forming part of a scaffolding joint according to any one of the preceding claims including the steps of subjecting T-section material to a shearing operation to remove an end portion of the stem of the T and thus leave a projecting portion of the bar of the T, deforming the projecting portion of the bar into abutment with the adjacent end of the stem, and simultaneously or subsequently upsetting the bar of the T in a direction generally away from the stem on at least one side thereof to form a protuberance.

14. A method according to Claim 13 wherein protuberances are formed simultaneously at either side of the stem.

15. A method according to Claim 13 or Claim 14 wherein the shearing operation produces a tapering of the stem in a direction towards the removed stem end portion.

16. A method according to any one of Claims 13 to 15 wherein the outermost extremities of the protuberances are flattened by a coining operation.

17. A method of making a scaffolding joint substantially as hereinbefore described with reference to Fig. 3 of the accompanying drawings. ~