(Bonded) Strain Gages
Meander-shaped resistors on a backing film are called strain gages. Are they subjected to elongation or compression strain they change their resistance. By means of a Wheatstone Bridge these changings can be evaluated.
Primarily force tranducers are measuring springs, which deform under load elastically. Strain gages are bonded in the areas of elongation and compression of the spring. Wired to a bridge the output signal is proportional to the load.
Strain gages are extremly flexible in there applications. They can be adapted very good to the spring material – steel or aluminum. Also there is no restriction concerning shape forming. Planar and spherical surfaces can be used for strain detection.
Force transducers with nominal loads of a few grams up to several hundred of tons can be realized. With optimal attunement of all components accuracies in the ppm range can be achieved. For a lot of industrial applications effort can be limited, because force transducers with accuracies of 0,2….2 % meet the requirements.
In the development of customized force transducers our target is to harmonize technical requirements and target price. In order to find the optimum of the “delta of requirements” consisting of technical demands, needed quantity and desired target price, Primosensor can fall back on thick film and thin film technology beside bonded strain gages.