Patent ID: 6029777
Filing Date: 2000-02-29
Classification: A62B,A63B

Abstract:
A descender for use in abseiling, or belaying, comprising:a base having a connection means for connecting the descender to a harness;an arm pivotally mounted on the base at a pivot axis extending generally normal to the base;the base having first and second spaced projections for engaging a rope, the projections both extending generally parallel to the pivot axis;the arm having a third projection for engaging a rope, the third projection extending generally parallel to the pivot axis, the third projection being located so that when the arm is pivoted towards the base the third projection is located to one side of a longitudinal axis passing through the first and second spaced projections on the base and is spaced further from the pivot axis than the second projection, but closer to the pivot axis than the first projection, characterised by;biasing means, for biasing the arm to rotate about the pivot away from the base, and stop means for preventing the arm from pivoting further than a predetermined angle away from the base; andsecond stop means for restricting the distance the arm can travel towards the base when the biasing means is overcome and the arm pivoted towards the base,a retention plate,whereby in use said descender being operable with a rope passing below the first projection, above and around the third projection and above the second projection, a resistance force applied to the rope is a maximum when the arm is pivoted so that the third projection is closest to the longitudinal axis, the descender being operable in two modes:a first mode in which the descender operates as a descender for controlling the rate of descent of a person sliding down the rope, in which mode the second stop means can be used to control the rate of descent; anda second mode wherein the descender is used with substantially no tension on the rope passing through the descender as a belay such that rope can be fed through the descender, in which mode the biasing means keep the arm and base apart to allow rope to be fed through the descender relatively freely but in which mode sudden increases in tension in the rope, cause the biasing means to be overcome and the pivot arm to be pulled towards the base thus locking the rope between the first and second projections and preventing uncontrolled descent.