WO1982002919A1

WO1982002919A1 - Collapsible scaffolding

Info

Publication number: WO1982002919A1
Application number: PCT/DK1982/000015
Authority: WO
Inventors: Fritz Torben Steffensen
Original assignee: Fritz Torben Steffensen
Priority date: 1981-02-18
Filing date: 1982-02-16
Publication date: 1982-09-02
Also published as: DK69681A; EP0072817A1

Abstract

In a scaffolding and formwork tower consisting of callapsible sections, each of the sections is in the form of flat, identical elements, each of which has a supporting upright (1) to the side of which are attached reinforcing rods (3) which engage with and are positively locked to an adjacent element. The ends of the uprights are brought together above projecting pins and are locked together by outward-facing lugs (6) on the projecting pins, which can be inserted into sleeves on the ends of corresponding columns which have inward-facing lugs (2), provided that the uprights are in extension of each other and that the lugs (6) lie in the spaces between the lugs (2), but cannot be pulled apart if, after insertion, the components are turned so that the lugs (6) and (2) are in line with each other. The elements can be assembled horizontally by insertion and locking together by subsequent turning.

Description

Collapsible scaffolding.

The present invention relates to a collapsible scaffolding of a kind which is made up of tower sections foried from rigid, flat elements, each of which has an upright element to the side of which are attached one^'or more reinforcing rods which, on the end facing away from the upright, are provided with a component which engages with an adjacent element, and in which two upright elements which fit together are provided with a projecting pin on one of the elements and a sleeve on the other element, with the help of which the supporting upright elements of the scaffolding are fitted together in extension of each other.

Some scaffolding of the aforementioned type does not require the supporting uprights to be locked together, ^'although the increased requirements for safety both during erection and during movement of the scaffolding with the help of a crane not only make locking together desirable or necessary, but also impose increased requirements for the locking together to be strong and reliable and incapable of failing as the result of oversights or other omissions, or because there are weak spots in the components, and in order to derive the maximum benefit from the advantages of horizontal assembly the importance of rapid locking together is a critical factor.

Methods have already been disclosed by which the supporting uprights of scaffolding can be locked together. A simple method is to provide the projecting pins and the ends of the uprights with holes or slots into which transverse pins or wedges are inserted manually after erection. This method is both time-consuming and unreliable, since it is possible to overlook one or more locking devices. The uprights can also be locked together with the help of multiple connectors with moving parts, although these are more expensive and are subject to failure as the result cf wear or cement drips, etc., preventing the moving parts fros functioning.

One simple and reliable method of locking together does exist, and is described in the Specification for British Patent ITo. 956991,

O PI although this relates to scaffolding in which the pins are inserted ^• in pairs and with the elements at an oblique angle, and where the locks do not permit the turning movement in the supporting uprights for the elements required for the erection of certain types of scaffolding, in addition to which the projecting pins have a special shape which requires a number of operations in order to manufacture them from sheet metal, unless they are required to be manufactured from machined rolled section or castings, all of which procedures make the projecting pins more expensive than the corresponding circular pin which can be made from sections of pipe or from circular upright ends.

Finally, locks have also been disclosed which consist of plates welded to the ends of the uprights, and which are either bolted together, or in which the plate on the end of one upright has two keyhole-shaped cut-outs and a corresponding plate on the end of the second upright has welded to it pins, each of which has a head which fits the keyhole, so that the plates are locked together by being turned relative to each other. These locks make the elements difficult to transport and to stack because of the projecting plates, and they also suffer from a manufacturing disadvantage since they cannot be made simply by forming projecting pins and lugs from the material used for the walls of the upright, but the plates must be welded to the ends of the uprights, which is more time-consuming and calls for inspection of the welds. Also disclosed are collapsible scaffoldings which are made up of flat frames, each of which has a supporting upright, onto which are attached reinforcing rods, onto the free ends of which are welded either a section of pipe with projecting pins which produce a connection between the ends of the uprights of two adjacent elements, as described in German Patent Application No. 2062 946 or also a length of angle-iron containing a hole into which the projecting pin of an adjacent element can be introduced, since this will have the simultaneous effect of locating the two uprights together, as described in Danish Patent Specification No. 105885. The supporting uprights for these types of scaffolding are not usually locked together at the ends, since they are erected by placing the uprights vertically above each other in such a way that each element must be raised to the top of the tower and engaged and interlocked at that point, which is a time-consuming and risky operation, and which also suffers from the disadvantage that the length of the elements and the distances between the uprights must be matched to the height of the scaffolding erector.

Finally, a type of scaffolding of the aforementioned type has been disclosed which can be assembled horizontally from flat elements, as described in Danish Patent Application No. 92/79- When this scaffolding is used in the form of units which will withstand a heavy load made up of a number of interlocked sections, then it is necessary for mechanical lifting gear to be available on site so that rational use may be made of the advantages associated with the erection of the scaffolding. On building sites where the scaffolding towers are both assembled horizontally by crane and are raised into position by crane, the advantages associated with the safe locking together of the sections are of great importance, although where no cranes are available it may also be desirable to be able to assemble the scaffolding towers horizontally from their component sections without the use of lifting gear, so that a number of pre-assembled towers may be made ready for lifting into position, if required, when a crane is available.

The purpose of the present invention is to produce a collapsible scaffolding of the aforementioned type which, with the help of simple and robust means and without increasing its cost to any great extent, will improve safety and increase the advantages associated with the horizontal assembly of flat elements into towers formed from several sections, achieved by fitting their supporting uprights together and locking them in position as an extension of each other without the use of moving pr projecting parts or of separate components, and without the use of manual connections. The purpose of the present invention is also to enable a scaffolding tower of the aforementioned type and with the ends of the uprights locked together to be assembled in a rapid

OMPI and reliable manner. The intended advantages are achieved because the scaffolding in accordance with the present invention is characterized by the original features indicated in the characterizing part of Patent Claim 1. This involves imparting a turning motion to the supporting uprights of the elements during assembly in such a way that, when they are positioned in extension of each other, they will be locked together simply by the turning motion, since this will cause all the lugs on the projecting pins to engage behind the lugs in the sleeves, when no lug will be able to move past another after assembly, thereby locking the elements of the scaffolding together, when each element after assembly will adopt the position in which it will be connected to another part of the scaffolding. Locking together will occur for as long as the reinforcing rods cf the elements remain attached with the scaffolding in its operating position. It is basically of no significance whether the projecting pins are attached in a permanent or detachable fashion to the ends of the uprights, or whether they are formed by the ends cf the uprights, and also whether the sleeve is formed by one e_.d of the upright or is attached to it, and whether or not the upright and the sleeve have the same internal diameter.

The scaffolding in accordance with the present invention may be designed in the manner indicated in Patent Claim 2. This embodiment enables the elements to be manufactured from standard tubing which is shaped in such a way that the insertion, fitting together locking of the uprights will take place rapidly and conveniently.

The scaffolding in accordance with the present invention, may also be designed in the manner indicated in Patent Claim 3. It is basically of no significance whether the projecting pins or the sleeves are of circular or non-circular cross-section, and whether the non-circular shape of the projecting pin or of the sleeve means that, instead of lugs, it incorporates slots into which the lugs of the corresponding component part are introduced as the elements are turned. Finally, the scaffolding in accordance with the present invention may be designed in the manner indicated in Patent Claiπ: 4. This embodiment enables all the ends of the uprights in the scaffolding to be identical, and also enables the elements to be locked together in scaffolding whose supporting uprights describe a single, non-relative turning motion during assembly. This may be achieved by designing the distance. pipes, or arms, for the intermediate links as knee-joints or lockable telescopic tubes, and by positioning them in such a way that, after assembly, they will combine in pairs to form diagonals in a rectangular tower. The present invention is described below with reference to the drawings, in which

Fig. 1 shows a perspective view from the side of a scaffolding tower in accordance with the present invention.

Fig. 2 shows a perspective view, with one of the components partially sectioned, of a method of making a connection in accordance with the present invention which is able to fit together and to lock in position two upright elements.

Fig. 3 shows a side view, with the lower component sectioned, of a method of connection of the same kind, but with two sets of lugs in each component.

Fig. 5 shows a view towards one end of an upright, with the internal component sectioned, for a method of connection which is able to fit together and lock in position the ends of two uprights, and which has one non-circular projecting pin. Fig. 6 shows a partially sectioned side view of a design for a connector which is able to fit together and lock in position two identical elements in accordance with the present invention.

Fig. 1 illustrates a scaffolding tower which in this case consists of three sections, each of which contains four identical elements, and whose supporting uprights- 1 are fitted together and locked in position in extension of each other by means of assembly and locking devices in accordance with the present invention. The two upper sections have connectors as shewn in Fig. 2, and the bottom assembly of the tower is shown in Fig. 7. Thus Fig. 1 shows the reinforcing rods 3 , the intermediate

_/^J__ ( links 7 and the arms 8 of the tower, as illustrated in Fig. 7, together with the supporting columns 1 .

Fig. 2 shows a partially sectioned perspective view of the ends of two circular uprights, one of which forms a sleeve with inward-facing lugs 2 , with the other upright 1 being formed in such a way that its end constitutes a projecting pin, at the base of which is a connecting component 4 and a part 5 which projects from it and which has on its outer surface four pressed lugs 6 . The component 4 is of circular cross-section and is essentially of the same diameter as the inside of the upright 1 , and the external diameter of the part 5 is smaller than the diameter of a circle passing through the outermost point of all the lugs 2 , at the same time as a circle passing through the outermost points of the lugs 6 is smaller than the internal diameter of the circle passing through the outermost points of the lugs 2 . Furthermore, all the lugs 2 are positioned in such a way that their contact surfaces are at an identical distance from the closest end of the upright, and that this distance is the same as the distance between the corresponding contact surfaces of the lugs 6 and the end of the upright closest to them. Finally, the overall width of the lugs 2 and 6 on the sleeve and on the part 5 on the other end of the upright is respectively smaller than the internal circumference of the upright 1 , at the same time as the positioning of the lugs relative to each other is such that they will face into the interjacent spaces during insertion. The connection is locked in position, after the components,have been inserted to the maximum extent, by turning one of the elements until the lugs 2 and 6 do not face entirely into the interjacent spaces.

Fig. 3 shows a side view, in the locked position, of the end of an upright 1 to which has been welded a projecting pin, to the outer part 5 of which are attached outward-facing lugs 6 in two circular rows. A sectional view is also provided of the end of the surrounding upright 1 , to which are attached inward-facing lugs 2 in two circular rows. The lugs in each row are positioned and dimensioned as described in Fig. 2.

Fig. 4 provides a view towards the end of an upright and, with the projecting pin sectioned, of a connector in accordance with the invention during insertion. Each part of the connector has two lugs in this instance, which are dimensioned in such a way that elements fitted with these connectors can be used to construct towers with three or more uprights in each section.

Fig. 5 provides a view towards the end of an upright and, with the projecting pin sectioned, of a connector for the fitting together and locking in position of the ends of two uprights 1 , one of which is in the form of a circular sleeve with inward-facing lugs 2 . The end of the other upright 1 is fitted with a triangular projecting pin which can be inscribed within a circle with approximately the same diameter as the .inside of the sleeve. The lugs 2 are arranged in such a way that the sides of the triangle are able to pass between them in the insertion position illustrated, and the edges of the triangle are provided with cut-outs 9 of sufficient depth to pass over the lugs 2 when turned, and by making the maximum distance between the lugs 2 and the end of their upright 1 the same as the maximum distance between the cut-outs 9 and the end of their upright, and also by making the minimum distance between the lugs 2 and the end of their upright greater than the minimum distance between the cut-outs 9 and the end of their upright, the lugs 2 can be positioned, by means of a turning motion, in the cut-outs 9 , causing the two uprights to be locked together.

Fig. 6 shows a partially sectioned side view of a connector which is able to fit together and lock in position the ends of two identical uprights 1 , when the three components are in extension of each other. The connector illustrated here is symmetrical about a central axis and at the same time about a plane which is perpendicular to the central axis. Immediately adjacent to the symmetry plane is a component 7 with a transverse measurement cf sufficient size to prevent i from being inserted into the ends cf the two uprights 1 which are to be fitted together and locked in position. The component 7 is fitted with an arm 8 which can hold the connector in the locked position and which can also perform another function at the same time, if necessary, if it adopts a position after assembly in which it is connected to .another part of the scaffplding. About the common central axis and in extension of each other- are two projecting pins facing away from the component 7 , each of which is identical with the projecting pin described in conjunction with Fig. 2, and which can be inserted into the sleeves illustrated in Fig. 2. As the projecting pin described here and the ends of the two uprights 1 are turned relative to each other, the ends of the uprights will engage with the pin and will be locked in position, thereby enabling the locking together of tower sections whose supporting uprights 1 describe an identical turning motion during assembly. This offers the advantage that all the ends of the uprights in the scaffolding can be identical.

The scaffolding offers advantages in use because it can be assembled lying down, in a simple manner and without the use of separate components, with or without the use of mechanical lifting gear, and is also safe, because all assemblies are positively locked together by strong connectors. Since the flat elements can be manufactured in flat welding jigs which are simple and are suitable for both manual and automatic welding, and since the elements can be produced from standard tubing, they are suitable for industrial manufacture, the cost of which can be reduced further by forming the projecting pins and the lugs of the uprights from the same material used for the ends of the uprights, which can be achieved by previously disclosed methods using rolling and pressing techniques.

Claims

Patent Claims.

1. Collapsible scaffolding of which the elements can be separated without deformation of the components, and of a type which is made up of tower sections produced from rigid, flat elements, each of which contains an upright element (1) to the side of which are attached, either in a permanet or in a ^■ detachable manner, one or more reinforcing rods f3) which, on the end pointing away from the upright ( 1 ) are provided with at least one component for interlocking with an adjacent element, and in which two upright elements (1 ) which fit together are provided with a projecting pin on one of the elements and with a sleeve on the other element, with the help of which the supporting upright elements ( 1 ) of the scaffolding are fitted together in extension of each other, c h a r a c t e r i z e d in that the projecting pin incorporates lugs (6) which face away from its central axis, and in that the sleeve on the same upright ( 1 ) incorporates lugs (2) which face towards its central axis, and in that the projecting pin and its lugs (6) and the sleeve and its lugs (2) are dimensioned and located in such a way that the projecting pin on one uprightd) can be inserted into the sleeve on another upright (1) when -all the lugs (6) on one component are positioned in the interjacent spaces between the lugs (2) on the other component, whilst the lugs (6) and (2) will not subsequently be able to pass by each other once the projecting pin and the sleeve have described a rotary motion relative to each other, so thstt the lugs (6) are positioned, either fully or partially, in line with the lugs (2), thereby locking the uprights (1) together, and finally in that the lugs (6) and (2) on each element are located in such a way in relation to a reinforcing rod (3) which is connected to the upright element (1) in question that the projecting pin is locked in position when the reinforcing rod (3) adopts the position in which it is to be connected to another part of the scaffolding.

2. A scaffolding in accordance with Patent Claim 1, c h a r a c t e r i z e d in that the sleeve is the circular end of an upright element ( 1 ) , and in that it has inward-facing lugs (2) which are attached to, or pressed from, the end of the upright, and in that the projecting pin is circular and is attached to, or formed from, the opposing end of an upright element (1), and in that'the projecting pin closest to the end of the upright has a circular locating component (4) whose external diameter fits the internal diameter of the sleeve, enabling them to slide and fit together , and in that the projecting pin beyond the component (4) extends as a cylindrical component (5) which has an external diameter smaller than the diameter of a circle passing through the outermost points of the free ends of the lugs (2) , and in that the compnent (5) has fitted to it, or pressed from it, outward-facing lugs (6) whose outermost points can be inscribed within a circle whose diameter is smaller than the internal diameter of the sleeve, but greater than the diameter of a circle passing through the outermost points of the free ends of the lugs (2) in the surrounding sleeve, and also in that all the lugs (2) and (6) are positioned and shaped In such a way that they have pairs of contact surfaces located at identical distances from the ends of their respective uprights and which engage with each other after having been turned into the locked position.

3. - A scaffolding.in accordance with Patent Claim 1, c h a r a c t e r i z e d In that the sleeve is circular and has inward-facing lugs (2), and in that the cross-section of the projecting pin is not circular and has edges whose outermost points-can be Inscribed within a cylinder with an external diameter which is approximately the same as the internal diameter of the sleeve, and in that the transverse measurement of the projecting pin at the mid-point of the surfaces which connect the edges is smaller thanthe diameter of a circle passing through the outermost points of the free ends of the lugs (2), and also in that the edges of the projecting pin have^"cut-outs (9) which are dimensioned and positioned in such a way that the projecting pin, after having been inserted to its full extent, can be turned In such a way that all the lugs (2) are introduced into their corresponding cut-outs (9).

O PI

4. A scaffolding in accordance with Patent Claim 1, c h a r a c t e r i z e d in that the upright element (7) has at each of its two free ends a projecting pin with outward-facing lugs (6),- and in that attached to the side of the same upright element (7) is an arm (8) which is located in such a way in relation to the lugs (6) on the projecting pin of the element that said lugs are engaged and locked in position by inward-facing lugs (2) in the surrounding sleeves of elements which are connected in extension of the projecting pins when the arm (8) adopts the position in which it is >-to be connected to another element in the scaffolding.

O PI