GB2328243A

GB2328243A - Ajustable brace for scaffolding

Info

Publication number: GB2328243A
Application number: GB9716984A
Authority: GB
Inventors: James Gerald Nolan
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-08-11
Filing date: 1997-08-11
Publication date: 1999-02-17
Anticipated expiration: 2017-08-11
Also published as: GB9716984D0; GB2328243B

Abstract

An adjustable brace for scaffolding has two telescoping male 1 and female 2 members, the male member having a set of external teeth 4,5 around part of its circumference, and the female member having a set of internal teeth 8,9 around part of its internal circumference. The male and female members may be rotated about their longitudinal axis between a disengaged position and an engaged position, so that in the disengaged position the members may be moved longitudinally with respect to one another, the external teeth passing between the internal teeth, and in the engaged position axial movement is prevented by the external teeth meshing with the internal teeth.

Description

ADJUSTABLE BRACE FOR SCAFFOLDING This invention relates to an adjustable brace for scaffolding.

In the construction of scaffolding for building works, it is well know to employ braces of adjustable length, as struts and ties, to accommodate the different lengths of brace required on site. These braces consist principally of two telescoping tubes, an inner, or male, tube having circular holes extending longitudinally along the tube, and an outer, or female, tube with a C-shaped clamp having a pin for locating in an appropriate hole in the inner tube, the clamp being secured by a nut and bolt to the inner tube. The outer ends of the tubes have recesses and spring clips for attaching the brace to scaffolding poles it is required to brace. This known brace takes some significant time to adjust and secure to the required length, and the present invention seeks to mitigate this disadvantage.

According to this invention, there is provided an adjustable brace for scaffolding comprising telescoping male and female members, mating interlocking engagement means provided on part only of the circumference of the outer and inner surfaces of the male and female members respectively, the circumferential extent of the interlocking engagement means being such that in one relative rotational position of the male and female members said members are longitudinally adjustable with respect to one another without said interlocking engagement means being engaged, and in another relative rotational position of the male and female members said interlocking engagement means are engaged.

Preferably, the engagement means on the male member comprises a set of external teeth and the engagement means on the female member comprises a set of internal teeth for meshing with said external teeth, such that in the engaged position a plurality of the external teeth are meshable with a plurality of the internal teeth and in the unlocked position the external teeth are passable past the internal teeth in a longitudinal direction without meshing.

Conveniently the set of external teeth and the set of internal teeth each comprise diametrically opposed pairs of teeth with diametric spaces between the opposed pairs such that rotation of the male and female members permits the opposed pairs of teeth to either engage one another or to locate in an associated space so that the internal and external teeth may pass along said associated space in the logitudinal direction.

Advantageously, cooperating slider means are provided on the male and female members whereby in the disengaged position the slider means on the male member co-operates with the slider means on the female member as the members move longitudinally with respect to each other.

Preferably, stop means is provided, whereby, in rotating the male and female members relative to each other from the disengaged position to the engaged position, the stop means acts to prevent the two members being rotated past a fully engaged position.

In an embodiment the slide means and stop means are formed on respective bars longitudinally extending on the male and female members.

Advantageously, the longitudinal extent of the set of external teeth is different from the longitudinal extent of the set of internal teeth.

Conveniently, the arcuate extent of each external tooth is different from the arcuate extent of each internal tooth, such that the male and female members can be assembled in only one relative orientation.

Advantageously, the male and female members are each provided at a respective outer end with releasable fixing means for attaching said outer ends to respective scaffolding poles.

Conveniently, the male member may be telescoped substantially completely within the female member.

The invention will now be described by way of example with reference to the accompanying drawing, in which: Figure l(a) shows in longitudinal cross-section a male member of an adjustable brace according to the present invention; Figure 1(b) shows in longitudinal cross-section a female member of an adjustable brace according to the present invention; Figure 2 shows an end view of the male member of Figure l(a) in the direction of double arrow-headed line A-A; Figure 3 (a) shows an end view of the female member of Figure l(b) in the direction of double arrow-headed line B-B; Figure 3 (b) shows a view of the inner end of the female member of Figure l(b) in the direction of double arrow-headed line C-C; Figure 4(a) shows a perspective schematic representation of the inner end of the male member of Figure 1(a); and Figure 4(b) shows perspective schematic representation of the inner end of the female member of Figure 1 (b).

In the Figures, like reference numerals denote like parts.

Referring to Figures l(a) and (b), an adjustable brace comprises two elongate telescoping hollow metal tubes, of circular cross-section, an inner, male member 1 and an outer, female member 2.

The male member 1 has an elongate tube 3, provided at one end with pairs of opposed external, upper, arcuate teeth 4 and external, lower, arcuate teeth 5, the total arcuate length of a pair of the upper and lower teeth being less than half the outer circumference of the male member 1. The upper teeth 4 advantageously have a greater arcuate length than the lower arcuate teeth 5. The teeth 4,5 may have a depth of 0.159 cm (1/16 inch) and extend longitudinally along the male member 1 at 1.57 teeth per centimetre (4 teeth per inch) for 66.04 cm (26 inches).

As best shown in Figure 4(a), there is also provided, at a left-hand end, as viewed along line A-A of the upper teeth 4, a longitudinally extending bar 6, having the same depth as the teeth 4, along at least the full longitudinal extent of the teeth 4, which acts as a combined slider and stop in a manner to be described.

The female member 2 has an elongate tube 7 having an inner circumference adapted to be a loose sliding fit with the male member 1. The female member 2 is provided at one end with pairs of opposed internal, upper, arcuate teeth 8 and internal, lower, arcuate teeth 9, the arcuate length of the upper teeth 8 being substantially the same arcuate length as the upper teeth 4 of the male member 1 and the arcuate length of the lower teeth 9 being substantially the same as the arcuate length of the lower teeth 5 of the male member 1. The upper teeth 8 therefore have a greater arcuate length than the lower arcuate teeth 9. The teeth 8,9 have a depth of 0.159 cm (1/16 inch) and extend longitudinally along the female member 2 at 1.57 teeth per centimetre (4 teeth per inch) for 5.12 cm (2 inches) but preferably have a slightly narrower width in the longitudinal direction than the teeth 4, 5 for ease of engagement. As best shown in Figure 4(a), there is also provided, at (a right-hand end as viewed along line B-B, (a left-hand end as viewed along line C C) of the lower teeth 9, a longitudinally extending bar 10, having the same depth as the teeth 9, along at least the full longitudinal extent of the teeth 9, which acts as a combined slider and stop in a manner to be described. Moreover, the internal teeth 8,9 are so deployed around the inner circumference of the female member 2, that the arcuate length of a gap 11 between the upper teeth 8 and the slider/stop bar 10 (to the left of the teeth as shown in Figure 3(b)) exceeds the arcuate length of the upper external teeth 4 of the male member 1, and the arcuate length of a gap 12 between the upper 8 and lower teeth 9 (to the right of the teeth 8,9 as shown in Figure 3(b)) exceeds the arcuate length of the lower external teeth 5 of the male member 1.

The male and female members 1,2 are each provided, at their outer ends, with an extension 13 which is generously perpendicular to the longitudinal axis of the members 1, 2, the extension being a flattened portion of tube and incorporating a recess 14, in an open end of the extension for receiving a scaffolding pole 16 substantially perpendicular to the longitudinal axis of the brace. In a known manner a spring clip 15 is attached to the extension for securing a scaffolding pole in the recess 14.

To assemble or adjust the length of the brace the male member 1 is clipped to a first scaffolding pole 16 and the female member 2 is rotated through about 90 degrees about its longitudinal axis relative to the male member 1 in a direction the direction of arrow-headed line 17 (see Figures 3(a), 3 (b) and 4(a), 4(b)) to a free position, such that on insertion of the male member 1 into the female member 2, a radial face 18 of the slider/stop bar 6 of the male member 1 abuts and slides against a radial face 19 of the slider/stop bar 10 of the female member 2 and the upper teeth 4 of the male member 1 pass through the gap 11 between the upper teeth 8 and the slide bar 10 of the female member 2, and the lower teeth 5 of the male member 1 pass through the gap 12 between the upper teeth 8 and lower teeth 9 of the female member 2. The slider/stop bars 6,10 thereby cooperate to prevent the edges of the teeth of the male member 1 snagging on the edges of the teeth of the female member 2 as the male member 1 is moved longitudinally with respect to and inside the female member 2.

When the brace is the required length, the female member 2 is rotated about its longitudinal axis, relative to the male member 1, back through approximately 90 degrees in a direction opposite to that shown by the direction of arrow headed line 17, to an engaged position, so that some of the upper teeth 4 of the male member 1 mesh with the upper teeth 8 of the female member 2 and some of the lower teeth 5 of the male member 1 mesh with the lower teeth 9 of the female member 2, the female member 2 being rotated until the ends 24 of the upper teeth 8 abut against a radial face 20 of the male stop/slide bar 6 and the ends 21 of the lower teeth 5 of the male member 1 abut against a radial face 22 of the female stop/slide bar 10, and the scaffold pole receiving extensions 13 of the male and female members 1,2 are parallel. The female member may then be clipped to a second scaffolding pole 23.

The relative sizes and deployment of the upper and lower teeth are so chosen that the larger upper teeth 4 of the male member will not pass through the smaller gap 12 of the female member, so that the brace cannot be assembled with the female member 2 inverted with respect to the male member 1.

Although the brace has been described as made of metal it will be understood that it could be made an other suitable, sufficiently strong material, and further, the male member 1 may be a rod and is not necessarily tubular.

Additionally, although the invention has been described in relation to a scaffolding brace, it will be understood that the invention could be applied in any situation where telescoping, elongate members of adjustable or fixed length are required, for example in legs of furniture, equipment or apparatus or for aerials, tripods or fishing rods.

Claims

1. An adjustable brace for scaffolding comprising telescoping male and female members, mating interlocking engagement means provided on part only of the circumference of the outer and inner surfaces of the male and female members respectively, the circumferential extent of the interlocking engagement means being such that in one relative rotational position of the male and female members said members are longitudinally adjustable with respect to one another without said interlocking engagement means being engaged, and in another relative rotational position of the male and female members said interlocking engagement means are engaged.

2. An adjustable brace as claimed in claim 1, wherein the engagement means on the male member comprises a set of external teeth and the engagement means on the female member comprises a set of internal teeth for meshing with said external teeth, such that in the engaged position a plurality of the external teeth are meshable with a plurality of the internal teeth and in the unlocked position the external teeth are passable past the internal teeth in a longitudinal direction without meshing.

3. An adjustable brace as claimed in claim 2, wherein the set of external teeth and the set of internal teeth each comprise diametrically opposed pairs of teeth with diametric spaces between the opposed pairs such that rotation of the male and female members permits the opposed pairs of teeth to either engage one another or to locate in an associated space so that the internal and external teeth may pass along said associated space in the longitudinal direction.

4. An adjustable brace as claimed in any preceding claim, wherein cooperating slider means are provided on the male and female members whereby in the disengaged position the slider means on the male member co-operates with the slider means on the female member as the members move longitudinally with respect to each other.

5. An adjustable brace as claimed in claim 4, wherein stop means is provided, whereby, in rotating the male and female members relative to each other from the disengaged position to the engaged position, the stop means acts to prevent the two members being rotated past a fully engaged position.

6. An adjustable brace as claimed in claim 5, wherein the slide means and stop means are formed on respective bars longitudinally extending on the male and female members.

7. An adjustable brace as claimed in claim 6, wherein the longitudinal extent of the set of external teeth is different from the longitudinal extent of the set of internal teeth.

8. An adjustable brace as claimed in claim 2, wherein the arcuate extent of each external tooth is different from the arcuate extent of each internal tooth, such that the male and female members can be assembled in only one relative orientation.

9. An adjustable brace as claimed in any preceding claim, wherein the male and female members are each provided at a respective outer end with releasable fixing means for attaching said outer ends to respective scaffolding poles.

10. An adjustable brace as claimed in any preceding claim, wherein the male member may be telescoped substantially completely within the female member.

11. An adjustable brace substantially as herein described with reference to and as shown in the accompanying drawings.