Abstract: A helical load cell is disclosed which is capable of accurately measuring axially applied forces, whether the force is applied axially within the diameter of the helical coil or outside of the coil diameter. A pair of strain gage modules are disposed on diametrically opposed surfaces of the coil. Each module includes a pair of transducer elements disposed orthogonally with respect to each other and at forty-five degrees relative to a neutral axis of the coil. The modules are coupled in an additive bridge circuit arrangement. In one embodiment, the modules are disposed along the outside diameter of the coil. In another embodiment, the modules are disposed along the inside diameter of the coil. In yet another embodiment, the modules are dispose on the upper or lower surface of the coil. In yet another embodiment, a second pair of strain gage modules is provided and coupled in a subtractive bridge circuit. The second pair of modules provides information as to the location of the applied load.

Abstract: A hydraulic lifting device, such as a forklift, is provided and is capable of dynamically measuring the weight of a load being lifted. A plurality of pressure measurements are taken during the lift for a period of time, which are stored in memory. A computer program is operated on by a microprocessor to process the pressure measurements to filter unwanted signals associated with vibration and other mechanical disturbances. The pressure samples processed by the computer program correspond to a portion of the lift during which acceleration of the forks has ceased, allowing a closer correspondence between the weight lifted and the pressure of the hydraulic fluid sensed.