Patent ID: 8779306

Claim:
A weight sensing apparatus for a lifting device, the weight sensing apparatus comprising: at least one lifting chain attached to a load-engaging device at a first end and a frame at a second end, the load-engaging device being movable with respect to the frame when a lifting force is applied via the at least one lifting chain; at least one force translating arm fixedly attached to a sensor shaft at a first end and rotatably attached to the at least one lifting chain at a second end, the second end of the at least one force translating arm being attached to the at least one lifting chain between the first and second ends of the at least one lifting chain; and a torque sensor mounted on the sensor shaft that is configured to measure a torque applied to the sensor shaft by the at least one force translating arm when the lifting force is applied to the at least one force translating arm by the at least one lifting chain.