EP1136639A1

EP1136639A1 - Method for manufacturing a fence, and fence obtained by said method

Info

Publication number: EP1136639A1
Application number: EP00201087A
Authority: EP
Inventors: Johannes Hendricus Josef Christianus Paaijmans
Original assignee: HERAS HOLDING CO BV
Current assignee: HERAS HOLDING CO BV
Priority date: 2000-03-24
Filing date: 2000-03-24
Publication date: 2001-09-26

Abstract

A method for manufacturing a fence consisting of two posts standing at a mutual distance and a lower and upper beam with a mesh of intersecting wires supported therebetween, which is distinguished by

aranging in or on the posts and/or the beams a channel-like fixing member provided with outward converging walls.
sliding an edge strip of the mesh into the opening of the channel,
tensioning the mesh by exerting a tensile force on the parallel channel-like members,
mutually fixing the posts while maintaining the tensile force, and
releasing the tensile force, with which method a fence is obtained which makes any further strengthening in the section unnecessary.

Description

The invention relates to a method for manufacturing a fence consisting of two posts standing at a mutual distance and a lower and upper beam with a mesh of intersecting wires supported therebetween.
Such a fence is commonly used as site perimeter fence, i.e. the bottom ends of the posts are each placed in a foot such that a number of site fences can be disposed adjacently of each other to bound a construction site or the like. Such a site fence must have a determined bending stiffness to be able to realize the desired protection and for this purpose the section filled by the intersecting wires is also bent into zigzag shape to obtain a determined bending stiffness. Other stiffening measures can also be applied, such as additional wires and the like.
The invention has for its object to change the method for manufacturing the fence such that the stiffness is obtained through a pretensioning.
The method according to the invention is distinguished by

arranging in or on the posts and/or the beams a channel-like fixing member provided with outward converging walls,
sliding an edge strip of the mesh into the opening of the channel,
tensioning the mesh by exerting a tensile force on the parallel channel-like members,
mutually fixing the posts while maintaining the tensile force, and
releasing the tensile force.

The desired pretensioning of the section can be obtained by placing the section of the intersecting wires under a tensile strain by means of the beams and/or the posts. The beams and/or the posts can be pressed or pulled apart after arranging of the edge strip of the section and be attached to each other in this loaded position.
This attachment can take place according to the invention with a butt weld, which enables a preparation of the components against corrosion without the protective layer then being damaged again.
The invention is further elucidated in the figure description hereinbelow of an embodiment. In the drawing:
fig. 1 shows a standing side view of a site fence according to the invention,
fig. 2, 3, 4, 5 and 6 show in perspective view the different steps of the method according to the invention for manufacturing a site fence,
fig. 7 and 8 show a perspective view respectively a standing section along arrow VIII-VIII in fig. 7 of a drawing machine for manufacturing a site fence according to the invention.
The site fence according to the invention consists of two posts 1 which are mutually connected at the top and bottom with an upper respectively lower beam 2, 3, between which a section of intersecting wires 4 is arranged. The posts protrude below the lower beam, whereby they can be placed in a hole of a site fence foot. It is thus possible to connect a number of such site fences to each other to obtain a continuous fence.
To enable manufacture of such a site fence the section 4 consisting of longitudinal wires 5 and transverse wires 6 is first manufactured in accordance with the known method wherein the transverse and longitudinal wires can be mutually welded to each other. Other sections of intersecting wires are possible within the scope of the invention. An edge strip is created along the four sides of the section by means of the outer longitudinal respectively transverse wires 5', 6'.
The posts and beams consist here of pre-drawn profiles, this such that the wall of a tube profile 7 is provided with an inward fold 8. The fold is such that the entrance is narrower than the thickness of the fold itself, see fig. 3. The entry slit of the fold has a width which is not much more than the thickness of for instance the transverse wire 6 respectively longitudinal wire 5. The fold widening towards the inside can however accommodate the intersecting wires, the longitudinal edge wire 5' and transverse wire 6.
Beam 2 is pushed on one side over the edge strip of the section as according to arrow P1 in fig. 2 so that the longitudinal edge wire 5' is received in the fold.
As according to fig. 4, the posts 1 are then pushed in the same manner over the edge of the section such that the transverse edge wires 6' come to lie in the folds thereof, see also fig. 5. The section is thus wholly enclosed along the edge in tubular profiles.
According to the invention it is now possible to exert a tensile force either on the posts such that they are moved apart, or on the beams or on both pairs. Because the edge of double thickness of the mat in the section resulting from the two intersecting wires cannot move through the entry slit of the fold in the tube, a tension will be applied to the section by exerting this tensile force. By then fixing the ends of the beams against the posts this tension remains present in the section even after the tensile force has been released.
Fig. 6, 7 and 8 show a possible drawing machine for placing beams 2 under tension, this drawing machine consisting of a supporting beam 10, 11 on which a catch 12 is arranged in which the transverse wires are held fast. A tensile stress can be exerted on the beams by moving the left-hand catch 12' in the direction of arrow P3. The ends of the beams 2, which are optionally pretreated, then only have to be welded or butt-welded or otherwise against the sides of the posts.
The invention is not limited to the above described embodiment. It is thus not necessary to make the section from intersecting wires which run parallel to the posts respectively the beams. Use can also be made of interwoven sections.
In addition, it is not directly necessary to arrange a fold in the tube form of the beam or post, but the fold can be mounted as separate profile against the outside of the random tube form of beam or post.
Within the scope of the invention the fold only has to have a narrowing entry slit such that the thickened peripheral edge of the section can be received therein and a tensile force can be exerted.

Claims

Method for manufacturing a fence consisting of two posts standing at a mutual distance and a lower and upper beam with a mesh of intersecting wires supported therebetween, characterized by

arranging in or on the posts and/or the beams a channel-like fixing member provided with outward converging walls,

sliding an edge strip of the mesh into the opening of the channel,

tensioning the mesh by exerting a tensile force on the parallel channel-like members,

mutually fixing the posts while maintaining the tensile force, and

releasing the tensile force.
Method as claimed in claim 1, characterized in that the beams are placed under a tensile force, and

for connection of the posts the beams are fixed with their ends to the posts while maintaining the tensile force,

the tensile force is released.
Method as claimed in any of the foregoing claims, wherein the beam and the post are tubular, characterized in that the channel-like fixing member is formed by an inward directed fold of the tube wall.
Method as claimed in claim 2, characterized in that the fixing of the beams to the posts is effected by a butt weld.
Fence consisting of two posts standing at a mutual distance with a mesh of intersecting wires supported therebetween, manufactured with the method as claimed in claim 1, 2, 3 or 4.