GB2137277A

GB2137277A - Scaffolding strut fastener

Info

Publication number: GB2137277A
Application number: GB08327279A
Authority: GB
Inventors: Peter Eric Gostling
Original assignee: GILTRIAN Ltd
Current assignee: GILTRIAN Ltd
Priority date: 1983-03-18
Filing date: 1983-10-12
Publication date: 1984-10-03
Also published as: GB8327279D0

Abstract

A scaffolding strut 1, adapted in use to form a diagonal brace, being part of a scaffolding structure, is of elongate, tubular construction and has, adjacent at least one end 2 thereof, a radially projecting mounting pin 3 on which is pivotally mounted a latch member 12, normally resiliently urged to a latching position and manually pivotal, for scaffolding assembly/disassembly purposes from its latching position to a non- latching position. <IMAGE>

Description

SPECIFICATION Scaffolding strut This invention relates to a scaffolding strut, particularly, though not exclusively, for use in constructing shoring or falsework structures.

In GB 1579825 and 1599646 is described a ledger, which in use is disposed horizontally, and which has an end connector fitting each ledger end; and a strut, which in use is disposed diagonally, to form a brace, and which is provided with a laterally extending mounting pin adjacent each strut end, each end fitting having a pair of additional circular apertures, one or both of which selectively, may receive a mounting pin. It is of course desirable, once such a mounting pin has been inserted, and the strut erected, that the mounting pin should not be inadvertently dislodged and accordingly the above-mentioned Patents disclose catch arrangements to preclude inadvertant dislodgement. However, these catch arrangements, comprising a pivotable, spring loaded safety finger carried internally of the strut, are relatively complex in design and hence costly to produce.

According to the present invention, there is provided a scaffolding strut adapted, in use, to form a diagonal brace, the strut being of elongate construction and having, adjacent at least one end thereof, a radially projecting mounting pin on which is pivotably mounted a latch member normally resiliently urged to a latching position and manually pivotable, for scaffolding assembly/disassembly purposes, from its latching position to a non-latching position.

Thus, the scaffolding strut in accordance with the invention, in providing a safety latching arrangement on the pin, advantageously allows a pin and latch sub-assembly to be produced and hence simplifies manufacture and/or assembly of struts, the latch member being automatically urged by the resilient loading into its latching position, upon emergence of the latch member from the pin receiving aperture of the end connector fitting, upon assembly, it being necessary, for disassembly purposes, for the user to depress the latch member e.g. by use of a thumb, against the action of the resilient loading.

Preferably, the latch member is provided with a constant surface, which may be linear or curved for sliding contact with a portion of the ledger end fitting during assembly of the scaffolding, to pivot the latch member progressively to its non-latching position, so that no manual pivoting of the latch member is necessary during assembly.

In principle, the latch member may be pivoted to the pin firstly at a location within the lateral dimension of the pin, or secondly outside the lateral dimension.

In an embodiment in accordance with the first proposal, the latch member is preferably provided adjacent the end of the pin remote from the strut, in which case the pin is provided with a housing e.g. a slot recess, hole, or aperture, capable of accommodating the latch member in the depressed, nonlatching condition thereof, so that in the latching position, the latch member projects beyond the lateral dimension of the pin, while in the non-latching position the latch member is displaced within the lateral dimension of the pin. Thus, in this embodiment, the contact surface would contact the internal periphery of the selected aperture.

In an embodiment in accordance with the second proposal, the pin may be provided with at least one, and preferably two, radially extending arms carrying a pivot for the latch member, the latter extending to both sides of the pivot to define a latching nose to one side of the pivot and extending to a location adjacent the end of pin remote from the strut, and a manually operable release lever to the other side of the pivot, the latching nose being adapted, in use, to engage a portion of a ledger to prevent inadvertent dislodgement of the pin from the pin receiving aperture. This arrangement gives the advantage that the release lever is on the "insertion" side of the aperture, rather than on the partially-obscured opposite side which provides for easier release either for disassembly of a scaffolding structure or of a strut which jams upon assembly.

Thus, in this embodiment, the contact surface would contact an external periphery of the ledger end fitting.

The resilient loading on the latch member may be effected by a spring, a rubber block etc., acting between the latch member and the pin, while with any embodiment, the mounting pin is preferably of circular section.

Although the mounting pin could be secured to the strut by welding, it is possible, in accordance with one embodiment, to provide a pair of diametrically opposite holes adjacent the strut end and to employ a pin of sufficient length not only to carry the latch member at the required distance from the adjacent periphery of the strut, but also to span the two diametrically opposite holes. With this arrangement the pin may be secured to the strut by a pair of circlips located in grooves in the pin periphery and having diameters greater than those of the diametrically opposite holes. Alternatively, a pair of split cotter pins may be provided.A preferred arrangement however is for one hole to be of smaller diameter than the other hole, and the pin provided with a shoulder, whereby a split cotter pin may be applied to an end of the pin remote from the latch member and projecting from the strut periphery.

In accordance with an alternative embodiment for use with a latch member pivoted at a radially spaced distance from the mounting pin, the strut end may be provided with one axially extending slot, with first and second axially spaced apertures located diametrically opposite the slot, to accommodate respectively, portions of the pin and latch member.

Thus, the first spaced aperture may be circular, to correspond to the external diameter of the pin, while the second spaced aperture may be elongate. With this embodiment, the pin may be provided with an enlarged collar serving firstly to dictate the penetration of the pin and hence the radial projection of the pin beyond the strut end, and secondly for welding to the periphery of the strut end. Conveniently, the strut is of tubular construction.

The scaffolding strut in accordance with the invention is particularly useful with the connector fitting described in our co-pending GB Patent Application No. 8307591.

The invention will now be described in greater detail, by way of examples, with reference to the accompanying drawings, in which: Figure 1 is a side elevation of a first embodiment of scaffolding strut in accordance with the invention, only one end of the strut being illustrated, for the other end is identical; Figure 2 is an end elevation of Fig. 1; Figure 3 is a view in the direction of arrow A of Fig. 1; Figure 4 corresponds to Fig. 1 and shows the strut end in the course of insertion into a pin-receiving aperture of an end fitting of a ledger; Figure 5 corresponds to Fig. 4 but shows the strut end fully inserted; Figure 6 is a view in the direction of arrow B of Fig 5; Figure 7 is a side elevation, corresponding to Fig. 3 but showing the strut end diagonally applied to an end fitting of a ledger;; Figure 8 shows an alternative embodiment of mounting pin to that illustrated in Figs. 1 to 7, with the latch member in its latching position; Figure 9 corresponds to Fig. 8 but shows the mounting pin partly in section and with the latch member in its non-latching position; Figure 10 is a view in the direction of arrow C of Fig. 8; Figure 11 is an end elevation of a second embodiment of scaffolding strut in accordance with the invention; Figure 12 is a view in the direction of arrow D of Fig. 11; and Figure 13 is an end elevation of Fig. 12.

In all the Figures, like reference numerals are accorded to like components.

In the drawings, a hollow, tubular scaffolding strut 1 is provided, adjacent each end 2 with a radially projecting mounting pin 3 of circular section adapted, in use, to be received in a correspondingly shaped aperture in an end fitting of a ledger, to be described in detail later.

In the embodiment of Figs. 1 to 7, the strut end 2 is provided with a first aperture 4 of diameter approximating to that of the pin 3, the latter having at one end a portion 5 of reduced diameter, to be received in a second aperture 6 located diametrically opposite the first aperture and approximating in diameter to that of the end portion 5, the latter having a diametrically extending through hole 7 to receive a split cotter pin 8 having bent wings 9, and thus to retain the pin 3 within the apertures 4 and 6 by means of the cotter pin 8 and a shoulder 9 on the pin 3 between the reduced diameter end portion 5 and the pin proper, so that a portion 10 of the pin 3 is located within the strut 1 and a portion 11 of the pin 3 projects radially from the pin 3.

At the end of pin remote from the strut, the projecting portion 11 of the pin 3 is provided with a latch member 12, and in detail the end of the pin remote from the strut is provided with a housing constituted by a slot 1 3 to define two webs 14 having co-axial bores 1 5 to receive a pivot 1 6 on which the latch member 1 2 is mounted and urged into a latching position - illustrated in Figs. 1 and 5 - by means of a wire torsion spring 1 7 extending between a notch 1 8 in the latch member 1 2 and a notch 1 9 in one web 1 4 of the projecting portion 11.In Figs. 4 to 7 the strut 1 in accordance with the invention is associated with an end fitting 20 of a ledger 21, which in use is located horizontally, as illustrated in Fig. 7 and is connected to a vertically extending standard (not shown) by means of a wedge connector 22, in a generally known manner. The end fitting 20 is provided with upper and lower circular receiving apertures 23 for engagement by pins 3 of the strut 1 in accordance with the invention, and in Fig. 7, the upper aperture 23 has been selected to receive the mounting pin 3 of an "upper" diagonally disposed strut 1 in accordance with the invention, which when assembled constitutes a brace for the scaffolding structure involved.In Fig. 4 the latch member 1 2 is shown displaced automatically into a non-latching condition, against the action of the spring 17, by the internal periphery of the aperture 23 progressively contacting a linear contact surface 24 of the latch member 1 2 which surface is in this position inclined with respect to the longitudinal axis of the pin - as the pin and hence the latch member progressively enters the aperture 23 and consequently, when the latch member 12, and in particular its contact surface 24, fully emerges from the opposite side of the aperture 23, the latch member 1 2 is automatically displaced by the spring 1 7 to itt latching condition, as illustrated in Fig. 5, afl abutment face 25 may abut an adjacent side face 26 of the end fitting 20, to prevent inadvertent dislodgement of the pin from its aperture. It follows that to disassemble from the position illus trated in Fig. 5, the latch member 1 2 is manually depressed from the position illustrated in Fig. 5 wherein a portion of the latch member 1 2 projects beyond the periphery of the pin 3, to a position in which the previously projecting portion i.e. the contact and abutment surfaces 24, and 25 respectively, are wholly located within the housing defined by the slot 13, so that the pin 3 can be withdrawn through the aperture 23.

In the pin embodiment of Figs. 8 to 10 a flat spring 1 7A is operable between an inner face 27 of the latch member 1 2A and a surface 28 definirig the bottom of the slot 13, with a stop 36 engaging a surface 37 at the terminal end of the pin 3A.

In the strut embodiment illustrated in Figs.

11 to 13 a pivot 16Ae.g. in the form of a spring dowel for the latch member I 2B is diametrically spaced from the pin 3B, by providing the pin 3B with two radially extending arms 29 which carry, towards their terminal ends, the pivot 1 6A. The latch member 1 2B extends to both sides of the pivot 1 6A to define a latching nose 30 to one side and a manually operable release lever 31 to the other side, the latching nose 30 having a curved contact surface 24A, so as to pivot the latch member 1 2B automatically to its nonlatching position (shown in chain dotted line) upon assembly, and an abutment face 25A to abut an adjacent side face 26 of an end fitting 20, again to preclude inadvertent withdrawal of the pin 3B from its receiving aperture in the end fitting. In this embodiment the end 2 of the strut 1 is provided with an axially extending slot 32, and with first and second axially spaced apertures 33 and 34 respectively located diameterically opposite the slot, the first corresponding in diameter to the pin 3B and the second accommodating the latching nose 30. Between the arms 29 extends a spring dowel 35, so that spring 1 7B may be operable between an adjacent surface of the pin 3B and a notch 38 in the release lever 31, the spring 17B normally urging the latch member 1 2B to the position illustrated in full line in Fig. 11.

Claims

1. A scaffolding strut adapted, in use, to form a diagonal brace, the strut being of elongate construction and having, adjacent at least one end thereof, a radially projecting mounting pin on which is pivotably mounted a latch member normally resiliently urged to a latching position and manually pivotable, for scaffolding assembly/disassembly purposes, from its latching position to a non-latching position.

2. A strut as claimed in Claim 1, wherein the latch member is provided with a contact surface for sliding contact with a portion of the ledger end fitting, during assembly of the scaffolding.

3. A strut as claimed in Claim 2, wherein the contact surface is linear.

4. A strut as claimed in Claim 2, wherein the contact surface is curved.

5. A strut as claimed in any preceding Claim, wherein the latch member is pivoted to the pin at a location within the lateral dimension of the pin.

6. A strut as claimed in any one of Claims 1 to 4, wherein the latch member is pivoted to the pin at a location outside the lateral dimension of the pin.

7. A strut as claimed in Claim 5, wherein the latch member is provided at a location adjacent the end of pin remote from the strut.

8. A strut as claimed in Claim 7, wherein the pin is provided with a housing to receive the latch member.

9. A strut as claimed in Claim 8, wherein the housing is in the form of a slot, recess, hole or aperture.

1 0. A strut as claimed in Claim 6, wherein the pin is provided with at least one radially extending arm carrying a pivot for the latch member, the latter extending to both side of the pivot to define a latching nose extending to one side of the pivot and extending to a location adjacent the end of the pin remote from the strut, and a manually operable release lever to the other side of the pivot.

11. A strut as claimed in Claim 10, wherein the latching nose is adapted in use to engage a portion of the ledger.

1 2. A strut as claimed in any preceding Claim, wherein the resilient loading on the latch member is effected by a spring or rubber block acting between the latch member and the pin.

1 3. A strut as claimed in any preceding Claim, wherein the pin is of circular section.

14. A strut as claimed in any preceding Claim, wherein the mounting pin is secured to the strut by welding.

1 5. A strut as claimed in any one of Claims 1 to 13, wherein a pair of diametrically opposite holes are provided adjacent the strut end, and a pin of sufficient length is employed not only to carry the latch member at the required distance from the adjacent periphery of the strut, but also to span the two diametrically opposite holes.

16. A strut as claimed in Claim 15, wherein the pin is secured to the strut by a pair of circlips located in grooves in the pin periphery and having diameters greater than those of the diametrically opposite holes.

1 7. A strut as claimed in Claim 15, wherein the pin is secured to the strut by a pair of split cotter pins.

18. A strut as claimed in Claim 15, 16, or 17, wherein one hole is of smaller diameter than the other hole, and the pin is provided with a shoulder, whereby a split cotter pin is applied to an end of the pin remote from the latch member and projecting from the strut periphery.

1 9. A strut as claimed in Claim 10 and any Claim appendant thereto, wherein the strut end is provided with one axially extending slot, and with first and second axially spaced apertures located diametrically opposite the slot, to accommodate respectively, portions of the pin and latch member.

20. A strut as claimed in Claim 19, wherein the first spaced aperture is circular and the second spaced aperture is elongate.

21. A strut as claimed in Claim 19 or 20, wherein the pin is provided with an enlarged collar serving firstly to dictate the penetration of the pin and hence the radial projection of the pin beyond the strut end, and secondly for welding to the periphery of the strut end.

22. A strut as claimed in any preceding Claim of tubular construction.

23. A scaffolding strut substantially as hereinbefore described with reference to Figs.

1 to 7 of the accompanying drawings.

24. A scaffolding strut substantially as hereinbefore described with reference to Figs.

8 to 10 of the accompanying drawings.

25. A scaffolding strut substantially as hereinbefore described with reference to Figs.

11 to 1 3 of the accompanying drawings.

26. A scaffolding structure, incorporating at least one scaffolding strut as defined in any preceding Claim.