Patent GB-435267-A (GB)
Title: Automatic release for parachutes
IPC: B64D17/52
Filed: 1934-03-14
Abstract: 435,267. Automatic parachute release. TRANUM, V. M., 34, Solway Avenue, Patcham, near Brighton, Sussex. March 14, 1934, Nos. 8097 and 17253. [Class 4] A device for releasing a parachute from its pack after launching from an aircraft comprises a member adapted to slide along a guide when the device is turned through an angle of a desired value, e.g. an angle exceeding 90‹ in order to effect the release of spring means associated with the rip cord. In one form, Fig. 1, the releasing device is shown in the position in which it is normally carried by the wearer of the parachute pack, it comprises tubes a, b secured by end plates c, c and transverse bolts d<1>, d<1>. A disc g slidable in tube a has secured to it a bolt h connected at its outer end to the rip cord of the parachute pack. Disc a is urged in the direction which would cause a pull on the rip cord by a spring f. The latter is held compressed by a trip lever having an arm j<2> extending into cylinder b. A ball i is normally located at the lower end of cylinder b and is adapted to roll down tube b and to trip lever when the device is turned through an angle exceeding 90‹. A safety catch comprising a spring loaded ball m which projects through a slot in tube b normally prevents releasing action by ball i. The ball m may be moved away from the slot by sliding nut l. The device may be used in conjunction with a parachute pack adapted to be opened by manual release means or by a static cord. A modification is described in which only one tube is employed, the trip lever being mounted in a casing attached to the exterior of the tube and having an arm projecting through a slot formed therein. In this form a sliding weight is adapted after tripping the lever to be moved in a reverse direction along the tube by the spring. In a further modification, Fig. 8, the device is combined with the rip cord ring. Rip cord z is attached to a pulley y<1> mounted on a spindle y<2> journalled in side walls of a casing u incorporating a rip ring u<1>. Secured to a smaller pulley y<3> also fast on shaft y<2> is one end of a cord z<1>, the other end being secured to the free end of a leaf spring w<2>. A lock bar x is pivoted to spring w<2> and extends through slots in spring anchorage w into a tube u<2>, and when spring w<2> is flexed to operative position, through a slot in casing u. In this position lock bar x is secured by a trip lever y adapted to co-operate with a ball v. The device is set by pulling on rip cord z thereby winding cord z<1> on pulley y<2> and flexing spring w<2>. This causes bar x to move into a position where it can be locked by trip lever y until such time as movement of the device causes ball v to roll down tube u<2>. A safety catch x<5> is fitted. Normal manual operation of the rip cord by a pull on ring w is not interfered with. In a still further modification the tripping device may be normally urged in a releasing direction but maintained in an engaged position by the movable weight. The multiplying device of Fig. 8 may be used in conjunction with spring means such as shown in Fig. 1, and such device may similarly be incorporated with a rip ring. Instead of tubular guides, guide bars may be employed over which the movable weight is threaded.