Mechanical fuse, a neck cord comprising a mechanical fuse and a method of connecting a mechanical fuse to a neck cord

摘要

The invention defines a mechanical fuse (20) for a neck cord (30). The mechanical fuse opens the neck cord when a pulling force component in a predetermined direction (70) exceeds a predetermined fuse force at which a rupture element (50) included in the mechanical fuse is designed to break. The rupture element has a break plane (51) at which breakage will occur when the pulling force component causes the stress in the break plane to exceed the value determined by said fuse force. The mechanical fuse further comprises a housing (60, 61, 62) that is arranged to guide the component of the pulling force in said predetermined direction (70) to the break plane whereas the transfer of a force component having another direction is suppressed.

主权项

1. A mechanical fuse for a neck cord comprising:
a rupture element, the rupture element comprising a break plane and first and second coupling means at either side of the break plane, the first and second coupling means being arranged for connecting to the neck cord, the rupture element being arranged to break at the break plane when a pulling force acting on the rupture element in a predetermined direction exceeds a predetermined fuse force; and a housing being releasably coupled to the rupture element wherein the housing is arranged to engage with the rupture element at either side of the break plane to prevent the rupture element from bending wherein the rupture element is arranged to break in a first portion and a second portion such that after breakage the pulling force causing one of the first and second portions to be decoupled from the housing and slide away from the housing thereby opening the neck cord.