WO2002038904A1 - Clamping connection comprising auxiliary aligning mechanisms - Google Patents

Abstract

The invention relates to a clamping connection for a display stand, comprising tubular parts (12) which have a uniform polygonal cross-section having end corners, and connection elements (10). A connection element (10) comprises a joint region (16) having front surfaces, from which at least one connecting part (14) extends, said connecting part being arranged on a front surface. Furthermore, at least one auxiliary aligning mechanism (22) is provided on the connecting parts (14). Said auxiliary aligning mechanism has an adjustment surface (24) which, in the clamping position, is parallel to the inner surface of the tubular part (12), and rests thereon. At least one auxiliary aligning mechanism (22) extends in the longitudinal direction over part of the connecting part (14), and the width thereof corresponds with part of the width of the inner surface of the tubular part (12).

Description

 CLAMP CONNECTION WITH ALIGNMENT AID

Field of the Invention

The present invention relates to a clamp connection for a presentation frame with which goods can be presented in showrooms. In particular, the invention relates to a clamp connection with which pipes and connecting elements can be assembled into racks in the form of shelves, showcases, cupboards and the like, the connection between the pipes and connecting elements being produced solely by clamping between pipe pieces and connecting elements without further securing elements becomes.

The invention further relates to

Presentation system that includes a variety of clamp connections of the type mentioned above.

Presentation systems, which are known as shelves, showcases, cupboards, tables or pedestals, for example from shops or other presentation rooms, such as exhibition stands, serve to attractively display various goods for the buyer or trade fair visitor. The individual elements from which the presentation systems are to be constructed should be used as flexibly as possible, and should be able to be assembled quickly, since they are often only required for a short time in a configuration, and still ensure good cohesion, even when loaded. Finally, it is desirable that the presentation systems can be manufactured inexpensively on the one hand due to the flexible use of different components and on the other hand due to the type of components. It is also required that the presentation systems create a visually appealing product carrier. State of the art

Presentation systems are known in the art which comprise a large number of clamp connections and meet the requirements mentioned.

In CH-A-454 555 a clamp connection is described which consists of a tube section with a square cross-section on the one hand and a counterpart which has the cross-sectional shape of a circular cylinder and is provided with four depressions or flats arranged offset by 90 ° to one another. In an assembly position in which the flats are directed towards the side faces of the square tube, the essentially circular-cylindrical tube piece can be pushed into the square tube piece. To establish the connection, the essentially cylindrical piece of pipe is then rotated through 45 °, as a result of which the non-flattened areas enter into a clamping connection with the sides of the pipe with a square cross section. According to CH-A-454 555, the connection described is also provided for connecting a plurality of pipes via a common node if the node is provided with a corresponding number of pipe pieces or counterparts.

A further development of the clamping connection described in CH-A-454 555 is shown in EP 1 030 067 AI. In this case, a connecting element is connected to a pipe section via a clamp connection, a presentation frame being able to be produced by means of several such connections. Spigots extend from the connecting element, which can be inserted into a pipe piece in a first position of the pipe piece for the spigot and can be brought into a clamping position with the spigot by twisting on the spigot. The clamping zones are formed by transverse ribs, which lie between the radial knots running around the pin, and have an upper peak. Furthermore, the clamping zones fall down to the adjacent flats.

It is common to both of the above-mentioned clamping connections that the clamping takes place between the clamping zones and on the inside pin side walls of a pipe piece, the individual clamping areas being linear, as a result of which an unstable equilibrium position is achieved in the clamping position.

A device for screwless fastening of a pipe is known from DE 15 75 319 B, in which a sleeve with a regular polygonal outer cross-section is inserted into a pipe with a geometrically similar inner cross-section, the pins to be fastened to the pipe in turn having axial projections that the Correspond to the number of polygon sides, so that the axial pin projections in the fastening state of the sleeve interact with locking grooves which are arranged in the polygon sides of the sleeve interior and which face the polygon corners of the tube.

Representation of the invention

The invention has for its object to provide a clamp connection in which the strength of a connection is as high as possible, while still ensuring inexpensive manufacture. Finally, elements that secure the clamping connection and that disrupt the visual impression should be avoided.

In addition, the invention has for its object to provide a flexible presentation system that is versatile and inexpensive to manufacture.

The stated objects are achieved by a clamp connection with the features of claim 1, a presentation system with the features of claim 12 and a connecting element with the features of claim 15. It should be noted that the term “distance” in this description and in the claims denotes the shortest distance between a point and a surface or between two surfaces or a line and a surface.

The invention is based on the idea of improving the correct fit of the tube piece and the connecting element to one another in the clamping position by providing alignment aids. In particular, instead of an unstable equilibrium position in the clamped state, there should be a stable equilibrium position in the clamped state. For this purpose, the alignment aids are shaped in such a way that they have an adjustment surface which, in the clamped position, is parallel to one side of the pipe section and lies against this side, so that the side of the pipe section is supported accordingly over a surface and not just over a line. This largely prevents undesired twisting, since initially a higher force has to be applied when the clamping connection is released. It should be noted in this regard that an adjustment surface in the sense of the invention can be realized not only by a continuous surface in the conventional sense, but also by other means, for example at least two appropriately positioned point-shaped elevations that define an adjustment plane that is not materially designed. An adjustment plane in the sense described should therefore also be encompassed by the term “adjustment surface”.

Increased resistance also occurs during assembly and disassembly. This necessity of applying an increased force can, however, be avoided by first placing the pipe section and the connecting element in the aligned position and then inserting them into one another parallel to the longitudinal pipe axis, so that the pipe section is aligned in the longitudinal direction on the alignment aids the connector is pushed on. Thus, the advantages of a relatively simple and quick assembly are still guaranteed, whereby, of course, the conventional assembly route, that is to say first completely pushed on and then rotated into the clamping position, can also be selected. At the same time, however, the fit of the connecting elements and the pipe pieces to one another is improved and the connection is made more stable against unwanted twisting or slipping.

Depending on the number and position of the alignment aids on the connecting piece of the connecting element, cost-effective production, for example by casting and simple post-processing by blasting, is also guaranteed. This means that the clamp connection and thus the entire presentation system remains inexpensive to manufacture.

Due to the fact that the alignment aids are in the assembled state, that is to say in the clamped state, within the pipe sections, they are not visible from the outside, so that an attractive appearance of a built-up frame or a similar presentation system is retained.

Advantageous embodiments are characterized by the remaining claims.

The polygonal cross section of the pipe section preferably has four corners, ie it is square. Other polygonal cross-sections (triangle, pentagon, hexagon ...) are also conceivable. The square shape of the pipe section ensures on the one hand that a relatively good production of the connecting pieces is possible, since four clamping zones and four insertion zones are to be provided, which are used for production by z. B. Casting does not place excessive demands on the tool. The clamping zones or insertion zones are each offset by 90 ° to one another, which Σ *. α

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Brief description of the drawings

The invention is described below purely by way of example with reference to the attached figures, in which:

FIG. 1 shows a connecting element according to the invention, from which three connecting pieces extend;

FIG. 2 shows a connecting element according to the invention, from which four connecting pieces extend;

FIG. 3 is an enlarged top view of a connecting element according to the invention, from which three pins extend;

FIG. 4 is a piece of pipe for producing a clamp connection with one of the connecting elements shown in FIGS. 1 to 3; and

FIG. 5 is a perspective view of a clamp connection according to the invention, two pipe pieces already being pushed onto a connecting element with three connecting pieces and one pipe piece being in the assembled state.

Ways of Carrying Out the Invention

FIG. 1 shows a perspective view of a connecting element 10 which, together with a pipe section 12 (see FIG. 4), forms the clamp connection according to the invention. -J.

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FIG. 4 shows a pipe section 12 for use with one of the connecting elements from FIGS. 1 to 3. The pipe section has a polygonal cross section with four corners. In particular, the cross section of the pipe section 12 is square. The inner and outer surfaces of the pipe section 12 are arranged parallel to each other.

With reference to FIG. 5, it will now be described how a pipe section 12 is joined with a connecting element 10.

First, the pipe section 12 is pushed over one of the connection pieces 14 of a connecting element 10, the inner corners of the pipe section 12 lying essentially over the apex regions of the clamping zones 18 of the connection piece 14. Accordingly, the inside of the tube of the pipe section 12 are arranged essentially above the insertion zones 14 during the insertion process.

The pipe section 12 is pushed onto the connecting element 10 until it abuts the node area 16. The pipe section is then rotated against the connecting element 10 with the aid of an assembly tool or by hand. In the illustrated case of a pipe section 12 with a square cross section and correspondingly designed connecting pieces on the connecting elements 10, a rotation of the pipe section by 45 ° is required. As a result of this rotation by 45 °, the pipe section 12 is rotated from a mounting position, which corresponds to the position of the pipe section designated 12 ′ in FIG. 5, into a clamping position. This clamping position is designated in FIG. 5 by reference number 12. In the illustrated embodiment, the end faces of the cube-shaped node area 16 are aligned with the outer surfaces of the tube piece 12 in the clamped position. Furthermore, there is almost no joint between the cube-shaped node area 16 of the connecting element 10 and the tube piece 12 in the clamped position. To in tΣ. μ- <! fd s: P-, W Pi fd Pi fd 3 Φ 3 ESI PJ fd for LQ <! μ * J Ijd! P ts <! «S: fd P = 03 PJ P = ι μ- 03 φ O Φ μ- φ fi OJ μ- O μ- OPPOP Φ o to 3 Φ P μ- μ- Φ oo tr er P tr rr HP ⁴ fi φ tr Φ tr 03 PPPP ü tr 03 P. P LQ 02 Ω PH Φ i P ⁴ Φ Φ 03 Φ Φ

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Resistance during assembly, which is caused due to the clamping zones and the alignment aids 22, can be overcome so far that the pipe section 12 is brought into a mutual clamping position with the connecting element 10. Due to the alignment aids 22, the clamping between the pipe section 12 and the connecting element 10 is not only produced as a linear clamping along well-defined apex lines of the clamping areas. Rather, the flat design of the alignment aids 22 prevent the connecting element 10 from being inadvertently rotated with respect to the pipe section 12.

Claims

Claims: 1. Clamping connection for a presentation frame, comprising pipe pieces (12) which have a uniform polygonal cross section with n corners, and connecting elements (10), wherein a connecting element (10) has a node area (16) with end faces, from which at least one connecting piece (14) extends on an end face; the connecting piece (14) n clamping zones (18) and n Has insertion zones (20) which are arranged uniformly and alternately on its outer circumference; a clamping zone (18) is formed by a raised area which is adjacent to one another Insertion zone (14) rises to an apex and to the other adjacent insertion zone (14) from Apex drops; the distances from the center of the cross section of a pipe section (12) to the inner surfaces of the Pipe pieces (12) the distances from the center of the Cross section of a connector (14) to the Essentially correspond to vertices, so that the clamping zones (18) correspond with the corresponding ones Inner surfaces of the pipe section (12) come into frictional engagement, while the insertion zones (20) are opposite Inner corners of the pipe section (12) come to rest, whereby a clamping position is formed; and rotated 360 ° / 2n from the clamping position Position of the connecting element (10) and Pipe piece (12) to each other Connection element (10) can be inserted into the pipe section (12) with a connection piece (14), the insertion zones (20) being opposite the Inner surfaces of the pipe section (12) and the clamping zones (18) opposite the inner corners of the pipe section (12); characterized in that at least one alignment aid (22) is provided on the connecting pieces (14), which has an adjusting surface (24) which, in the clamping position, is parallel to an inner surface of the tubular piece (12) and bears against this, the at least one Alignment aid (22) extends in the longitudinal direction over part of the connecting piece (14) and has a width which corresponds to part of the width of an inner surface of the pipe piece (12). 2. Clamping connection according to claim 1, characterized in that the polygonal cross section of the tube piece (12) has four corners. 3. Clamping connection according to one of the preceding claims, characterized in that the node area (16) is cube-shaped. 4. Clamping connection according to one of the preceding claims, characterized in that the clamping zones (18) and insertion zones (20) extend substantially over the entire length of the connecting pieces (14). 5. Clamping connection according to one of the preceding claims, characterized in that on each of the connecting pieces (14) clamping zones (18) and insertion zones (20) are arranged. 6. Clamping connection according to one of the preceding claims, characterized in that the alignment aids (22) connect to the node area (16). 7. Clamping connection according to one of claims 1 to 5, characterized in that the alignment aids (22) by the Node area (16) spaced apart are arranged in the area of the connecting piece (14) remote from the node area (16). 8. Clamping connection according to one of the preceding claims, characterized in that n alignment aids (22) are provided. 9. Clamping connection according to one of the preceding claims, characterized in that the alignment aids (22) have a width which essentially corresponds to the width of the clamping zones (18). 10. Clamping connection according to one of the preceding claims, characterized in that the node area (16) has an internal thread (26) on a free end face. 11. Clamping connection according to one of the preceding claims, characterized in that the end faces of the node area (16) have the same cross-sectional shape as the pipe sections (12), the tube outer surfaces are aligned in the clamping position with the node outer surfaces and almost no joint between the node area (16) in the clamping position. and pipe section (12) is present. 12. Presentation system comprising a plurality of clamp connections according to one of the preceding claims, which can be assembled into a frame. 13. Presentation system according to claim 13, characterized in that the tube pieces (12) are at least partially provided with fastening devices for goods carriers. 14. Presentation system according to claim 12 or 13, further comprising an assembly tool that a channel element, the is adapted to the cross section of the pipe sections, and includes a lever attached to it. 15. Connecting element (10) for use in a clamp connection according to one of claims 1 to 11.