Hottinger Baldwin Measurement, Inc.

Edward Freymiller

Harry E Lockery

The load measuring sensitivities of transducers, such as beam type transducers, or the like, are desensitized by connecting a desensitizing resistance in series with the strain gages attached to a transducer so that these desensitizing resistances become part of the respective bridge arm in which the corresponding strain gage is located. In a group of four transducers, each carrying, for example two strain gages, the transducer which has the lowest sensitivity is ascertained. Thereafter, the sensitivities of the other three transducers are reduced by the desensitizing resistors connected directly in series with the strain gages in the other three transducers so that all have substantially the same sensitivity as the mentioned lowest initial sensitivity in the group of transducers. Any influences of these desensitizing resistors from one bridge arm to another bridge arm are considered in the derivation of the correct desensitizing resistances. Thereafter, a further sensitivity equalization may be achieved by mechanically increasing the sensitivity of those transducers in the group still having a lower sensitivity than the lowest sensitivity transducer in the group. Such mechanical sensitivity increase involves removing material from the sensing portion of a transducer for example by filing or grinding until all transducers of a group have the same sensitivity within an acceptable tolerance range, for example, 0.02%.

Growing community of inventors

Lynnfield, MA, United States of America

Edward Freymiller