Patent ID: 8276461

Claim:
Lifting member ( 1 ) intended to transmit all or a portion of a longitudinal lifting force between a lifting device and a load to be lifted, including: a proximal portion ( 1 a ) conformed to be fixed to the lifting device, a distal portion ( 1 b ) adapted to be connected to the load, a longitudinal portion ( 1 c ), extending from the proximal portion ( 1 a ) in the direction of the distal portion ( 1 b ), and adapted to be stretched elastically by the portion of the longitudinal lifting force, wherein the distal portion ( 1 b ) of the lifting member comprises a rotary latch having a “T”-shape, the “T”-shaped latch including a shoulder portion having an oblong shape, and wherein: the longitudinal portion ( 1 c ) of the lifting member ( 1 ) includes at least one longitudinal passage ( 1 d ), an optical stress sensor ( 2 ) is inserted into said at least one longitudinal passage ( 1 d ) and is fixed to the lateral wall of said at least one longitudinal passage ( 1 d ), said optical stress sensor ( 2 ) produces a signal imaging the longitudinal stretching of the longitudinal portion ( 1 c ) of the lifting member ( 1 ), and connecting means ( 3 ) are provided for transmitting the signals from the optical stress sensor ( 2 ) to means ( 4 ) for receiving and analyzing the signals from the optical stress sensor ( 2 ).