Torque tester
Encyclopedia
A torque tester is used as a quality control device to test or calibrate torque
controlled tools. This includes electronic torque wrenches, click torque wrenches, dial torque wrenches, electric screwdrivers, air screwdrivers, pulse tools, cordless screwdrivers, nutrunners, and torque screwdrivers. Today’s advanced torque testers include the ability to measure in clockwise and counter-clockwise directions, convert to 8 engineering units (in·oz, in·lb, ft·lb
, N·m
, cN·m, kgf·cm, gf·cm, kgf·fm), 3 modes of operation (peak, 1st peak, track), and include a National Institute of Standards and Technology (NIST) certificate.
, similar to a load cell
, is an electronic device used to convert torque into an electrical signal. This conversion is indirect and happens in two stages. Through a mechanical arrangement, the torque being sensed deforms a strain gauge
. The strain gauge converts the deformation (strain
) to electrical signals. A torque transducer usually consists of four strain gauges in a Wheatstone bridge
configuration. Torque transducers of one or two strain gauges are also available. The electrical signal output is typically in the order of a few millivolts and usually requires amplification by an instrumentation amplifier
before it can be used. The output of the transducer is plugged into an algorithm
to calculate the force applied to the transducer. There are several styles available for torque transducers. Rotary, stationary (reaction), and inline are used for different calibration and audit purposes.
Torque
Torque, moment or moment of force , is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist....
controlled tools. This includes electronic torque wrenches, click torque wrenches, dial torque wrenches, electric screwdrivers, air screwdrivers, pulse tools, cordless screwdrivers, nutrunners, and torque screwdrivers. Today’s advanced torque testers include the ability to measure in clockwise and counter-clockwise directions, convert to 8 engineering units (in·oz, in·lb, ft·lb
Foot-pound force
The foot-pound force, or simply foot-pound is a unit of work or energy in the Engineering and Gravitational Systems in United States customary and Imperial units of measure. It is the energy transferred on applying a force of 1 pound-force through a displacement of 1 foot...
, N·m
Newton metre
A newton metre is a unit of torque in the SI system. The symbolic form is N m or N·m, and sometimes hyphenated newton-metre...
, cN·m, kgf·cm, gf·cm, kgf·fm), 3 modes of operation (peak, 1st peak, track), and include a National Institute of Standards and Technology (NIST) certificate.
Transducer
A torque transducerTransducer
A transducer is a device that converts one type of energy to another. Energy types include electrical, mechanical, electromagnetic , chemical, acoustic or thermal energy. While the term transducer commonly implies the use of a sensor/detector, any device which converts energy can be considered a...
, similar to a load cell
Load cell
A load cell is a transducer that is used to convert a force into electrical signal. This conversion is indirect and happens in two stages. Through a mechanical arrangement, the force being sensed deforms a strain gauge. The strain gauge measures the deformation as an electrical signal, because the...
, is an electronic device used to convert torque into an electrical signal. This conversion is indirect and happens in two stages. Through a mechanical arrangement, the torque being sensed deforms a strain gauge
Strain gauge
A strain gauge is a device used to measure the strain of an object. Invented by Edward E. Simmons and Arthur C. Ruge in 1938, the most common type of strain gauge consists of an insulating flexible backing which supports a metallic foil pattern. The gauge is attached to the object by a suitable...
. The strain gauge converts the deformation (strain
Strain
Strain can refer to:* Strain , variants of plants, viruses or bacteria; or an inbred animal used for experimental purposes* Strain , a chemical stress of a molecule...
) to electrical signals. A torque transducer usually consists of four strain gauges in a Wheatstone bridge
Wheatstone bridge
A Wheatstone bridge is an electrical circuit used to measure an unknown electrical resistance by balancing two legs of a bridge circuit, one leg of which includes the unknown component. Its operation is similar to the original potentiometer. It was invented by Samuel Hunter Christie in 1833 and...
configuration. Torque transducers of one or two strain gauges are also available. The electrical signal output is typically in the order of a few millivolts and usually requires amplification by an instrumentation amplifier
Instrumentation amplifier
An instrumentation amplifier is a type of differential amplifier that has been outfitted with input buffers, which eliminate the need for input impedance matching and thus make the amplifier particularly suitable for use in measurement and test equipment...
before it can be used. The output of the transducer is plugged into an algorithm
Algorithm
In mathematics and computer science, an algorithm is an effective method expressed as a finite list of well-defined instructions for calculating a function. Algorithms are used for calculation, data processing, and automated reasoning...
to calculate the force applied to the transducer. There are several styles available for torque transducers. Rotary, stationary (reaction), and inline are used for different calibration and audit purposes.