Classifications

• • E—FIXED CONSTRUCTIONS
  • E06—DOORS, WINDOWS, SHUTTERS, OR ROLLER BLINDS IN GENERAL; LADDERS
  • E06B—FIXED OR MOVABLE CLOSURES FOR OPENINGS IN BUILDINGS, VEHICLES, FENCES OR LIKE ENCLOSURES IN GENERAL, e.g. DOORS, WINDOWS, BLINDS, GATES
  • E06B9/00—Screening or protective devices for wall or similar openings, with or without operating or securing mechanisms; Closures of similar construction
  • E06B9/02—Shutters, movable grilles, or other safety closing devices, e.g. against burglary
  • E06B9/08—Roll-type closures
  • E06B9/18—Roll-type grilles
• • E—FIXED CONSTRUCTIONS
  • E04—BUILDING
  • E04C—STRUCTURAL ELEMENTS; BUILDING MATERIALS
  • E04C2/00—Building elements of relatively thin form for the construction of parts of buildings, e.g. sheet materials, slabs, or panels
  • E04C2/30—Building elements of relatively thin form for the construction of parts of buildings, e.g. sheet materials, slabs, or panels characterised by the shape or structure
  • E04C2/42—Gratings; Grid-like panels
  • E04C2/421—Gratings; Grid-like panels made of bar-like elements, e.g. bars discontinuous in one direction
  • E04C2/426—Gratings; Grid-like panels made of bar-like elements, e.g. bars discontinuous in one direction with continuous bars that remain unconnected at crossing points of the grid pattern, e.g. with undulating bars

Definitions

• This invention relates to a complete production line for burglarproof grilles, and a grille which acts as a physical barrier against possible intruders.
• This kind of grille is usually intended for mounting in front of, and sometimes behind, doors and windows in public buildings, assembly halls, shops, offices, factories, business premises or showrooms.
• Figure 1 shows a front view of a portion of grille in accordance with this invention.
• Figure 2 shows two alternative embodiments of the tie 2 on figure 1 ,
• Figure 3 ' shows a principle diagram of the production line according to this invention.
• Figure 4 shows an enlarged detail of module 70 on figure 3, and Figure 5 shows the feeding method for the ties 2.
• the invention is based on the idea that, instead of using a material of such thickness that it cannot be cut through, one uses material whose hardness prevents such cutting. Sawing through the material is too time consuming. Tests have shown that two men equipped with an 18" long bolt cutter cannot cut through drawn, carbon-enriched, steel wire of spring steel quality or better, when the wire has a diameter of 6.5 mm or more. Moreover, such a wire is so stiff that, when taking into account the fact that the material cannot be cut through, it will not be necessary to have high strength requirements for the spacers or ties placed between each longitudinal wire of the grille. Practical tests have shown that if a hardened steel chain is embedded in every eighth plastic tie, the grille will be impenetrable.
• Such steel wire is commonly available on the market in considerable lengths wound on spools or reels. Generally, 6.5 mm wire is sold in lengths of approximately 4000 m, and will suffice for approximately 1000 square meters of burglarproof grille. It is also a very low-cost material compared to alternative materials for grilles.
• Figure 1 shows parts of two wire lengths 1 and 3.
• the wires 1 and 3 are linked with ties 2 at the point where the wires are closest to each other. At the points where the wires 1 and 3 are furthest apart from each other, they are, each independently of the other, linked with other wi_r___ not shown on the drawing.
• Two preferred embodiments of the ties 2 are illustrated in alternative 1 and alternative 2 on figure 2.
• the ties of both embodiments are made of a hard-wearing plastic, with a hardened steel reinforcement in every eighth tie.
• the use of plastic has several advantages. The ties are easy and cheap to manufacture in large quantities; they are well suited to the processes of an automated production line for grilles; and the material has only a minimum wear-and-tear effect on the nylon coating of the steel wire.
• the result is a strong and environmentally neutral grille with good clearance for light.
• the grille is therefore perfectly suitable for display windows and the like.
• the mesh size suggested on figure 1 may be varied.
• the ends of the steel wires are inserted into aluminium sections which may be of existing design.
• Various designs for such frames or sections can easily be ordered from manufacturers and do not constitute a part of this invention.
• Figure 3 illustrates the schematic principle of the production line which is described in detail as follows.
• Reference point 10 symbolizes a spool or reel of spring steel wire.
• the wire 1 is drawn through a straightening press 15 which has horizontal and vertical rollers (a single set of rollers is shown on the figure). Although the wire will have acquired a curved shape when stored on the reel 10, cold drawing in the straightening press will result in a perfectly straight wire ready for the next steps in the production line.
• the next module 20 consists mainly of two shaping wheels which give to the straight wire the wave shape illustrated on figure 1. Great accuracy in reproduction of the individual bends or waves in the bending module is essential.
• stamping sheets mounted between the teeth of the bending wheels - these stamping sheets acting in a similar way as the die base of a die cutter - and by adjusting the pressure on the wire section, one reaches a force which is exactly sufficient to exceed the material's yield point.
• One thus achieves sufficient accuracy of reproduction of the bend so that trimming at a later stage of manufacture, and assembly of the ties on the wires at a further stage of manufacture may be 5 effected automatically to give an accurate, finished grille.
• the bending module 20 delivers whole lengths of ready o shaped wire into a annealing module 25, and the wire is sent further to a heating module equipped with a heater 30.
• a propane burner or a similar type of equipment heats the segment of wire which passes through the heater to a temperature of 250 to 300 degrees Celsius. 5
• the wire leaves the heater through a narrow slot.
• a roller is mounted close to the slot to provide support and assist in the further displacement of the wire down the production line.
• the wire 0 Before reaching the heating module 30, the wire 0 has gone through the processes involved in the annealing module 25.
• a measuring device to register the length of the wire is provided in the form of a pulse counter over a running wheel.
• a sliding plate mounted on a heating unit for annealing 5 two segments on each wire length is provided in the form of a pulse counter over a running wheel.
• a sliding plate mounted on a heating unit for annealing 5 two segments on each wire length The next device is a new sliding plate mounted on a pneumatic cooling unit situated before the water-cooling unit.
• the wire is annealed at the points where it will later be trimmed during the manufacturing process.
• the 0 wire is annealed on two short segments, usually of 2 cm length. On those segments, the wire is heated to a temperature of approximately 700 degrees Celsius. The annealing points are then air-cooled and subsequently water-cooled.
• 5 Module 40 is a coating box where the earlier mentioned nylon powder is sprayed on to the wire. The correct quantity of electrostatically charged powder is blown into the box and sticks electrostatically to the wire where it melts.
• the temperature of the wire is brought down to near room temperature. In a preferred embodiment, this is effected with the help of water jets at a predetermined temperature and pressure.
• support rollers are mounted to feed the wire to the next module.
• a counting and trimming module is schematically illustrated on figure 3 as reference point 60. Trimming of the wire is effected in this module by clamping the wire to a carriage. The wire is trimmed with flying shears and the carriage slides back. The lengths cut to size are placed in a predetermined direction in a collecting trough 70.
• the collecting trough has a feeding device controlled by pneumatic pistons 84 and 90 as shown on figures 4 and 5 in a preferred embodiment. Trimming of the wire is controlled by a PLC which keeps track of the annealing points, and counts down to zero starting from a number determined by a preset counter.
• the PLC starts first of all the heating module 30. After a while the rest of the line is switched on. This can of course be effected by sensing the temperature in the heating module. However, the stability of the equipment makes it possible to determine the necessary delay between starting the heating module and switching on the rest of the line.
• the wire is fed to the bending module 20.
• the machine rejects unusable material left over from the previous day's production.
• the new order of grilles is then effected as the correct number of wires of each length passes through the machine. When this is effected, this part of the production line is switched off until the next order is started.
• Assembly of the grille starts when a length of wire hanging in the collecting trough 70 is dropped down into the feeding unit 82 of the assembly table 80 and is placed against the guide bar 86.
• a number of ties 2 await in the slots of the slide bars 88, as illustrated on figure 5.
• the correct positioning of the ties in the slide bars 88 is effected by pneumatic pistons 90, controlled by the PLC.
• the wire length is pushed forward by the piston 84.
• the ties will move up and down the slide bars 88.
• the next length of wire drops down and is pushed forward when the next set of ties is in position in the slide bars 88.
• Every other length of wire is positioned on the table 82 with its first bend upward, while the lengths in between those are positioned with their first bends downward. Also, the first set of ties is positioned in the first, third, fifth, etc. slide bar, while the second set of ties is placed in the second, fourth, sixth, etc. slide bar.
• the production line of this invention permits the rational and time-saving manufacture of a product, while at the same time reducing material consumption.
• the grille is in itself a product which has clear advantages over existing burglarproof grilles, and it is considered an integral part of this invention.

Landscapes

• Engineering & Computer Science (AREA)
• Architecture (AREA)
• Structural Engineering (AREA)
• Civil Engineering (AREA)
• Wire Processing (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

Family

ID=19892566

Family Applications (1)

Country Status (4)

Cited By (2)

Citations (8)

• 1989
  • 1989-11-10 NO NO894483A patent/NO894483D0/no unknown
• 1990
  • 1990-11-12 WO PCT/NO1990/000170 patent/WO1991007565A1/en not_active Application Discontinuation
  • 1990-11-12 AU AU67182/90A patent/AU6718290A/en not_active Abandoned
  • 1990-11-12 EP EP19900916534 patent/EP0453540A1/en not_active Withdrawn

Patent Citations (8)

Also Published As

Similar Documents

Legal Events