Rotating Torquemeters have a stationary housing and a rotating shaft. When inserted between a motor and pump (for example), the rotating shaft experiences the torque which exists in the system due to the mechanical power transfer. Which begs an immediate question:

"How do you get a signal from a rotating shaft to a stationary output circuit?"

Prior to 1960, the unsatisfactory solutions were to use conductive brushes which rub against the shaft as it moves, or to use liquid mercury contacts. However, in 1960, a young Electrical Engineer, Mr. Sydney Himmelstein , invented and patented the Rotary Transformer device which spawned the Chicago-based manufacturer: S. Himmelstein & Co. ( "S.H.C.").

Today, 50 years later, S. Himmelstein & Co. continues to dominate the Torque Measurement market, with a wide array of Rotating Torquemeters to address a multitude of mechanical applications and to satisfy various customer preferences for electronic interfaces.

They measure torque in (mostly) dynamic applications, such as the torque in a spinning shaft between a motor and a pump, or engine and load. Though they can just as readily measure static torque, in applications such as tightening of fasteners or twisting of structural supports.