A torque sensor, torque transducer or torque meter is a device for measuring and recording the torque on a rotating system, like an engine, crankshaft, gearbox, transmission, rotor, a bicycle crank or torque transducer. Static torque is fairly very easy to measure. Dynamic torque, on the contrary, can be difficult to measure, as it generally requires transfer of some impact (electric, hydraulic or magnetic) from the shaft being measured to a static system.
A good way to make this happen is always to condition the shaft or even a member linked to the shaft with a number of permanent magnetic domains. The magnetic characteristics of such domains will vary in accordance with the applied torque, and thus can be measured using non-contact sensors. Such magnetoelastic torque sensors are typically employed for in-vehicle applications on racecars, automobiles, aircraft, and hovercraft.
Commonly, torque sensors or torque transducers use strain gauges placed on a rotating shaft or axle. Using this method, a way to power the strain gauge bridge is essential, and also a way to get the signal from your rotating shaft. This can be accomplished using slip rings, wireless telemetry, or rotary transformers. Newer varieties of torque transducers add conditioning electronics plus an A/D converter for the rotating shaft. Stator electronics then look at the digital signals and convert those signals to some high-level analog output signal, like /-10VDC.
A far more recent development is the use of SAW devices linked to the shaft and remotely interrogated. The strain on these tiny devices since the shaft flexes may be read remotely and output without making use of attached electronics on the shaft. The probable first use within volume will be in the automotive field as, of May 2009, Schott announced it possesses a SAW sensor package viable for in vehicle uses.
An additional way to 3 axis load cell is by way of twist angle measurement or phase shift measurement, whereby the angle of twist resulting from applied torque is measured by making use of two angular position sensors and measuring the phase angle between the two. This technique is used within the Allison T56 turboprop engine.
Finally, (as described in the abstract for people Patent 5257535), if the mechanical system involves the right angle gearbox, then the axial reaction force felt by the inputting shaft/pinion may be linked to the torque experienced by the output shaft(s). The axial input stress must first be calibrated from the output torque. The input stress could be nanzqz measured via strain gauge measurement in the input pinion bearing housing. The output torque is definitely measured employing a static torque meter.
The torque sensor can function such as a mechanical fuse and is an important component to obtain accurate measurements. However, improper setting up the torque sensor can harm the device permanently, costing money and time. Hence, the torque sensor has to be properly installed to make certain better performance and longevity.
The performance and longevity in the compression load cell and its reading accuracy will likely be impacted by the design of the driveline. The shaft becomes unstable on the critical speed in the driveline and results in torsional vibration, which can harm the torque sensor. It is actually essential to direct the strain to an exact point for accurate torque measurement. This aspect is typically the weakest point of the sensor structure. Hence, the torque sensor is purposely made to be among the weaker aspects of the driveline.