Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F42—AMMUNITION; BLASTING
  • F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
  • F42B6/00—Projectiles or missiles specially adapted for projection without use of explosive or combustible propellant charge, e.g. for blow guns, bows or crossbows, hand-held spring or air guns
  • F42B6/003—Darts

Definitions

• This invention relates to a dart of the kind present- ' ed in the preamble to claim 1.
• Darts are used in the game of darts, where the darts are thrown at a circular target of a material into which the darts can penetrate, e.g.- a felt-like mat ⁇ erial, coiled-up paper or cardboard, or hair disposed in a parallel manner, e.g. horsetail hairs with the hair direction at right-angles to the plane of the target.
• the target is divided into fields of various numerical value, and these fields are separated by steel wire so that there can never be any doubt con- cerning in which field the dart is sitting.
• the object of the invention is to provide a dart which does not fall to the floor when it strikes the steel wire, but which upon impact with the wire changes dir ⁇ ection and hits the actual target, and thus always re ⁇ main sitting in said target.
• the point of the dart When the dart hits the target, the point of the dart is held in its foremost position in the barrel. Upon impact with the steel wire, the point will be pushed right back into the chamber and the dart continues al ⁇ ong the same trajectory, but now with a shorter point, and will thus hit the target one more time, but at a place which is shifted slightly.
• the reason for this is that a dart which is thrown at a target will always follow a parabolic trajectory, a so-called throw-para ⁇ bola. The length of' the trajectory will depend on the relevant player's throw curve, throwing height and technique. The dart, however, will never be able to hit the target at right-angles to the plane of the target, since this is always vertical.
• the dart accor ⁇ ding to the invention is therefore arranged in such a way that when it strikes the steel wire, the dart's trajectory is extended so that the dart hits twice in the same throw, but the new hit will always be slight ⁇ ly displaced from the original hit on the wire. This displacement is sufficient to ensure that the dart always remains sitting in the target and never re- bounds .
• the dart according to the invention is preferably de ⁇ signed as presented and characterized in claim 2, in that a simple construction is achieved which is rel- atively inexpensive to produce.
• the dart according to the invention is preferably de ⁇ signed as presented and characterized in claim 3, in that the construction achieved has very few parts, and thus in a simple manner the dart can be arranged to allow the point to be moved a distance into the barrel by a suitable force depending on the dart's own weight.
• darts are produced with a weight of from 15 g to 35 g in steps of 1 g, and the force which is applied to the dart point and causes it to be moved freely into the bore can be changed in a simple man ⁇ ner, namely by merely changing the O-ring. If the characteristics of the dart should change after very frequent use, one can also simply change the O-ring whereby the dart regains the characteristics it had when new.
• the dart provided will have quite definite aerodynamic characteristics, as opposed to the known darts where the point is dispos ⁇ ed in a resilient or frictional manner, in that the point in these known darts can be displaced when thrown very hard. With the dart according to the in- vention, such a displacement of the point of the dart in connection with the throw is impossible.
• the dart according to the invention is constructed as characterized in claim 5, one can change the char ⁇ acteristics of the dart as required or, after having made a number of trial throws, one has obtained pre ⁇ cisely that displacement length which gives the best results in connection with the precise way in which one throws.
• Claims 6 and 7 present advantageous ways in which the setting of the length of the point's displacement can be carried out.
• fig. 1 shows a dart according to the invention in cross-section
• fig. 2 shows a slightly different form of the actual point.
• a dart according to the invention is shown in fig. 1- of the drawing, the dart being shown with the dart barrel 10 and the shaft 6 cut through in a plane sec ⁇ tion.
• the barrel 1 0 which is elongated and of the same outer form as the generally-known darts , there is a thread 5 at the rear end by means of which a normal flight shaft 6 is secured.
• the shaft 6 is of the commonly-known type , for example of plastic , nylon , metal or a combi- nation hereof.
• the shaft 6, and the feathers secured herein but not shown, do not form part of the inven ⁇ tion and will not be described further.
• the dart barrel 10 has an elongated, central chamber, for example a bore 12, which is open at the front end of the barrel in the direction of throw.
• the bore 12 is narrowed down at the foremost end, thus enabling a point 1 to be secured.
• the one end of the point which is held in the bore 12 has a thick portion, e.g. a spherical portion 2, so that the point 1 cannot be drawn out through the front end of the barrel.
• the * thick portion 2 of the point is secured in the posi ⁇ tion shown in the drawing by means of an O-ring 3 or another frictional element.
• the O-ring 3 is fitted, for example, in an internal annular groove 11 in the barrel 10.
• the weight of the barrel 10 Upon impact with- the. steel wire, the weight of the barrel 10 will cause the point's spherical part 2 to be pressed through the hole in the O-ring 3 immed ⁇ iately, after which it is free to move in the long- itudinal direction in the bore 12. Consequently, the dart is actually given a shorter point, shortened namely by the length 7, in that the double arrow 7 indicates the amount by which the point can be moved. Immediately hereafter, a new hit is made, but because of the arc of the traj ectory, the point of the dart is given a new point of impact with respect to the target .
• the length 7 is in the order of 6-15 rrm, preferably approx. 10 mm.
• the point 1 is very easy to change if it is damaged, and no parts can be assembled incorrectly.
• a dart point 1 with a rounded end part which is slightly different.
• the end part 13 is produced by securing the point and working the end part in a hammer-like manner to create a thick por ⁇ tion, which is then machined to form a rounded-off friction area 13.
• a setting element 4 with • a limiting surface 8 for the movement of the point 1.
• the setting element 4 can either be replaced by anoth ⁇ er, or be disposed in the core in a movable manner, e.g. by means of a thread or friction, thus enabling the movement possibility 7 of the point to be changed or adjusted completely as required.
• the setting ele ⁇ ment 4 is made of a suitable material, e.g. plastic or metal, in that consideration must be given to the fact that its weight forms part of the weight of the dart.
• the surface 9 on the barrel 10 can be machined in the same way as the commonly-known darts, e.g. by profil- ing, knurling or quite smooth and shiny.
• the barrel 10 is normally made of metal or metal alloys such as nic ⁇ kel, tunsten, brass or similar materials with suitable weight and workability.
• the O-ring 3 is an ordinary O-ring, of rubber, plastic or synthetic material, and the point 1 is made of steel or hardened metal alloys.
• the O-ring is lubrica ⁇ ted with a suitable lubricant, for example acid-free vaseline or vaseline with a silicone content.

Landscapes

• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Aiming, Guidance, Guns With A Light Source, Armor, Camouflage, And Targets (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=8129584

Family Applications (1)

Country Status (4)

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Family Cites Families (5)

• 1984
  • 1984-08-24 DK DK404384A patent/DK404384A/da unknown
• 1985
  • 1985-08-16 AU AU47759/85A patent/AU4775985A/en not_active Abandoned
  • 1985-08-16 EP EP19850904240 patent/EP0190320A1/en not_active Withdrawn
  • 1985-08-16 WO PCT/DK1985/000079 patent/WO1986001418A1/en not_active Ceased

Non-Patent Citations (1)

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