WO1989002958A1

WO1989002958A1 - Lattice joint

Info

Publication number: WO1989002958A1
Application number: PCT/SE1988/000497
Authority: WO
Inventors: Jan Erik Falk
Original assignee: Vector Design Ab
Priority date: 1987-09-25
Filing date: 1988-09-23
Publication date: 1989-04-06
Also published as: SE8703715L; SE8703715D0; SE462533B

Abstract

The present invention refers briefly to a lattice work knot for use in the erection of lattice work constructions of tube-like elements (26). The lattice work knot, which is adapted to be mounted for obtaining a varying number of studs (3, 18, 19) and even in various angles in relation to the body (11), comprises thus a plurality of studs (3, 18, 19) over which the ends of the tube-like element (26) may be drawn when the lattice work is built. Each stud (3, 18, 19) comprises an arm portion (23) which is a part of the stud (3, 18, 19) onto which the tube-like elements (26) are drawn and which has at least three arms (30), the diameter of the circle of which the arms (30) form radii being greater than the inner diameter of the tube-like element (26) adapted to be drawn over the stud. The arm portion (23) extends at right angles from a plane surface (12) forming an abutment surface for the tube-like element (26) drawn over the arm portion (23).

Description

LATTICE JOINT

The present invention refers to lattice work constructions, in particular to a knot forming part of such constructions.

Lattice works are used on many fields both for occasional use and for stationary use. The present invention has particular reference to the first range of use and has been developed in connection with lattice work used in connection with exhibi¬ tions and similar fields of use to define a specific exhibition show case. In vast exhibition halls it is necessary for every exhibitor to define in some way just his own range, his show case which in this case is to be done with some kind of wall- and roof-like construction. This construction should suitably be easily adaptable to various requirements, be cheap and simple to manufacture and mount and be usable several times.

Even if the invention is described in connection with lattice work for this specific range, it is obvious that it may be used also on many other fields where mountable lattice work constructions are used independently of whether they are temporary or adapted to be used during an extended time.

It is known in itself to built-up lattice work of tube sections mutually connected with the aid of knots. Such knots may be spheres provided with symmetrically positioned threaded holes. In these holes studs are inserted onto which the ends of the tube pieces are drawn. Such a knot will be heavy because it contains much material and it is difficult to manufacture. The result of these both facts is that the knot will be expensive while simultaneously it involves other problems such as a heavy lattice work construction and much mounting work.

There are also lattice work knots having a great number of studs extending in different directions. Much material is wasted in these knots during manufacture but not all this

? i-fn/ z-^'-'y material is made use of. Thus, the knots have a great number of extending studs which will not be used in the construction of the lattice work. In this connection it should also be mentioned that the appearance of the knot is not without importance.

Moreover, these two known knots have studs of circular cross- section and the tubes urged onto them will be permanently deformed which means that after repeated use their play in relation to the studs will be great enough to render the construction unstable.

The present invention is intended to eliminate the above mentioned problems. This purpose is obtained by the lattice work construction of the type indicated in the claims which also indicate the specific characteristic features of the invention.

Hereafter, the invention will be described by reference to the enclosed drawing in which

FIGURE 1 is an exploded view of the parts constituting one type of a lattice work knot and

FIGURE 2 is a schematical section along the plane II-II in Fig. 1 but complemented with a tube section mounted on the stud.

The lattice work knot according to the invention comprises several parts adapted to be combined optionally, such combina¬ tions permitting many embodiments in a simple and stable way and forming, in the finally mounted state, a faceted sphere.

Fundamentally, the lattice work knot according to the inven¬ tion comprises a central body 1 which is fundamentally cross- shaped with a ring 2 from which four arms or studs 3 extend straight outwardly in the same plane. At the junction of each stud 3 with the ring 2 a plane facet surface 4 is formed with which the stud 3 forms a right angle. When a simple lattice work construction without depth is built, the central body 1 acts as lattice work knot.

Below the central body 1 a lock 5 is shown which is used to cover the range within the ring 2 in order to give this simple knot a satisfactory appearance. The lock 5 is provided with shoulders 6 corresponding to recesses 7 in the axially facing sides of the ring 2. Moreover, the lock has a central hole 8 for a screw that may be used to attach the lock to the central body 1 in an easily detachable way, the screw in this case being screwed into a hub 9 in the centre of the ring 2 of the central body 1.

As an alternative to the lock 5 there is provided an upper part 11 having the appearance of a truncated four-sided pyramid on which every side forms a facet surface 12 which when the upper part 11 is attached to the central body 1 forms an angle of 45° with the facet surfaces 4 on the central body 1. The upper part 11 is also provided with shoulders 13 corresponding to the recesses 7 in the central body and it also has a central hole 14 for a screw 15 by means of which the upper part 11 may be releasably attached to the central body 1 by attachment to the hub 9 thereof.

The upper part 11 has a through groove in each facet surface 12, said groove 16 extending from the shoulder 13 up to the plane upper surface 17 of the upper part 11, said grooves 16 being shifted 45° in relation to the studs 3 when the upper part 11 is mounted on the central boby.

The grooves 16 are intended to receive loose studs 18, 19, two of which are shown while there are several other possible embodiments. Each loose stud is provided with an abutment surface 20 adapted to abut against the facet surface 12 on either side of the groove 16. A web 21 having a thickness corresponding to the width of the groove 16 and a height corresponding to the material thickness of the upper part 11 extends diametrically over the abutment surface 20 and has an outer flange 22 which abuts against the lower side of the upper part. 11 at the groove 16 when the stud 18, 19 is anchored in the groove 16.

Each stud 3, 18, 19 has a cross-shaped cross-section and in the loose studs 18, 19 the cross-shaped portion 23 extends from a base 24, 25, the side of which opposite the cross- shaped portions 23 constituting the previously mentioned abutment surface 20.

The base 24 of stud 18 is a circular disk having the same diameter as the length of the arms of the cross-shaped portion 23 and the same thickness throughout. This means that when a tube section 26 is drawn over the cross-shaped portion 23 it also will be drawn over the base 24 to abut against the adjacent facet surface 12.

The base 25 of stud 19 is also a circular disk but with a greater diameter than the length of the arms of the cross- shaped portion 23 and in cross-section this disk is wedge- shaped in such a way that the base is thin at the one end of web 21 and thick at the other end. The wedge-shape is such that the stud 19 extends at an angle deviating from 90° in relation to the facet surface 12. By inserting the web 21 into the groove 16 with the one or the other end first it is possible to cause stud 19 to extend from the facet surface 12 at two different angles. The side of base 25 facing the cross- shaped portion 23 is completely plane and at right angles to the cross-shaped portion 23 and extending beyond the arms of the cross-shaped portion 23. This means that at the outer edge of the base the surface is formed against which a tube section drawn onto stud 19 will abut.

Two opposed arms of the cross-shaped portion 23 are provided with a through hole 27, the arms for strengthening reasons having been widened to form beads 28 about the holes 27. At their outer edges the arms of the cross-shaped portion 23 are terminated by a practically straight cut. This appears from arms 29 shown horizontally in the drawing which are terminated by transverse surfaces 30. Hereby, the attached tube section 26 is formed to a certain extent to be deformed about these edge surfaces 30 and as the two opposed arms 29 have a slightly greater extension than the inner diameter of the attached tube section 26, the deformation to which the tube section is exposed during attachment to the stud will become so intensive that the tube section will be locked on the stud by some kind of forced fitting. However, in the mantle surface of the tube section 26 there is provided a through hole 31 opposed to the hole 27 in the stud when the end edge of the tube section 26 abuts against a facet surface or the corresponding surface of base 25. For the purpose of securely locking the tube section 26 in question on the corresponding stud 3, 18, 19 an easily removable locking pin 32 is inserted through the hole 31 of the tube section 26 and the hole 27 of the stud.

Due to the fact that the tube section when mounted on the respective stud will not require an extension of the diameter of the tube section but only a non-permanent deformation of the shape proper of the tube section, the tube sections may be used several times and still will be supported by the respec¬ tive stud. However, in order to increase the friction between the stud and the tube section the edge surfaces 30 of the arms 29 may be provided with small projections or similar exten¬ sions.

The lattice work knot described above thus comprises several parts which may be composed at will and need to comply with the requirements regarding the shape of a lattice work of the type mentioned initially. In most cases the variable lattice work knot composed of loose parts has sufficient strength to be used directly and after use to be disassembled and again assembled for renewed use. However, when very big lattice work constructions are concerned which also may be exposed for dynamic stresses, for example, when the lattice work construc¬ tion is exposed to movements, it may be suitable to glue together the parts of the lattice work knot to form a solid unit.

It will thus be appreciated that the initially mentioned purposes have been achieved by the present invention. It is to be noted that the specific advantage of the invention resides in the fact that the tube sections connecting the various knots in a lattice work are solidly connected thereto primari¬ ly by the fact that the studs are provided with the arms of the cross-shaped portions and in the second place by the abutment surface against which the ends of the tube sections abut along their entire circumference, the locking pins merely acting as a protection against unintentional removal of a tube section from a stud.

A mounted lattice work comprising tube sections and knots may have a weight of several hundred kilograms and due to the building technique a certain automatic locking action will prevent the lattice work from disintegration. The non-desir¬ able mobility characteristic of previously known lattice work constructions causing these constructions to hang down when they for example were used as the roof of a show case, will not appear in lattice work built with the aid of lattice work knots according to this invention. In other words, while prior art lattice work constructions gave an impression of being in danger of collapse, a lattice work built with the aid of knots according to this invention retains the same shape from assembly to disassembly.

The expert on this field will appreciate that many variations of this invention may be applied. However, such variations are considered to fall within the frame of the invention as defined in the attached claims.

Claims

1. Lattice work knot comprising a plurality of studs (3, 18, 19) extending from a body (2, 11) in predetermined directions, characterized in that each stud (3, 18, 19) comprises an arm portion (23) onto which a tube section forming part of the lattice work may be drawn, that each arm portion (23) comprises at least three arms (30) and that the diameter of the circle in which the arms (30) are radii is larger than the inner diameter of the tube section (26) adapted to be drawn over the stud (3, 18, 19).

2. Lattice work knot as claimed in claim 1, characterized in that the arm portion (23) is composed of four arms.

3. Lattice work knot as claimed in claim 1 or 2, charac¬ terized in that the arm portion (23) of the stud (3, 18, 19) extends at right angles from a plane surface (12) forming an abutment surface for the tube section drawn over the arm portion (23) .

4. Lattice work knot as claimed in any of the preceding claims, characterized in that it comprises a central body (1) having integral studs (3) and an upper portion (11) on which loose studs (18, 19) may be attached.

5. Lattice work knot as claimed in claim 4, characterized in that the loose studs have a base (25) of wedge-like cross section permitting, by 180° turning of the stud about its longitudinal axes, two different angular positions in which the stud may extend from its mounting surface.

6. Lattice work knot as claimed in claim 5, characterized in that the base (25) extends outside the arms and forms a plane abutment surface for the tube section (26) drawn over the arm portion (23).