Patent GB-1498708-A (GB)
Title: Dartboards
IPC: B29C65/02
Filed: 1976-08-05
Abstract: 1498708 Dartboards DRK Ltd 5 Aug 1976 [5 May 1975] 18820/75 Heading A6S A method of making a dartboard consists of bundling together monofilaments of a plastics such as polypropylene in parallel arrangement, cutting the bundle into short lengths and assembling the lengths on a flat surface with the filaments extending in the direction of the axis of the dartboard, compressing them into a disk and then joining the filaments by melting, welding, &c. to make the rear face of the dartboard. The bundle is wrapped tightly in strip or sheet material, e.g. paper gum strip, crepe paper, polythene tape, or is shrink-wrapped in plastics, and cut into short lengths. These short pads are placed on a flat surface and compressed into a disk by a metal band, &c. The tops of the pads are levelled. A hot silicone &c. coated plate is applied to melt the filaments and form a skin linking them together. After an interval, the hot plate is removed, and a rigid sheet of plywood, chipboard, plastics, &c. applied to the still hot filaments, adhering the sheet to them. Alternatively, the filaments may be allowed to cool, the sheet then being glued to the filaments. In a further modification, the filaments are glued to the back panel without first melting. The filaments may act as fibre optics, so that with a backing sheet printed in colours, &c. the scoring sectors, &c. are visible from the front. The backing sheet may be transparent or translucent, e.g. coloured, and illuminated from behind. Alternatively, the backing sheet may be a normal paper coil dartboard, printed on both sides, to provide a double-faced dartboard. The backing sheet may have a smooth surface for use with sucker darts on the back. The backing sheet may be covered with fabric to receive "Velcro" (registered Trade Mark) ended darts, &c. In another form, the hot plate is applied to the fibres for a sufficient time to produce a thicker skin and thus do away with a backing sheet. Alternatively, the hot plate may be applied to both sides of the fibres, forming a double skin, printed on one or both sides of the board. Such a board may dispense with the usual circumscribing metal band, and instead may have a tape, plastics or other decorative band. The outer periphery of the board may also be heated, to produce a cohesive skin on all surfaces. To fit, the usual wire divisions, either conventional securing means may be used, or shallow indentations formed in the board face by a die, to half-sink the wires into the surface. Alternatively, the division wires may themselves be heated, so as to melt the plastics fibres locally and hold the wires in place. If moulded plastics divisions are used instead, they may be adhered to the surface of the dartboard by hot plate or ultrasonic welding, with or without pegs which enter the depths of the fibres. Numerals may be similarly affixed. The decoration of the board surface may be by foil blocking, hot dyeing, spraying, silk screen printing, &c. or the fibres may themselves be coloured. In the latter case, the divisions of the dartboard are in the form of flat strip, pre-assembled by welding, and the coloured filaments filled into the appropriate spaces between the strips. To allow removable replacement and rotation of the numeral rings, evenly spaced holes are drilled from the back of the board, and metal or plastics tubes inserted. The tubes are then welded ultrasonically. Wire or plastics pegs are provided on the numeral rings; the pegs may be bifurcated, or have barbs, &c. to fit into the tubes.