Abstract: This invention relates to an improved digital weight measuring and computing apparatus with automatic zero correction which automatically corrects the zero indication of the apparatus.The weight measuring apparatus comprises a scale which employs a load cell and strain gauge to develop an analog voltage representing the weight on the scale. An analog-to-digital converter is then employed to change the analog voltage into a digital representation of the load on the scale. The digital converter provides a digital indication in addition to the digital indications employed to indicate the weight on the scale. The additional digital indication represents fractions of the least weight increment indicated of the weight on the scale. The additional digital indication is then employed to control the generation of a zero correction factor and this factor is then combined with the weight indications from the scale to indicate the correct weight of articles placed on the scale.

Abstract: In a plural scale system such as a parts counter having a minor scale for measuring the weight of a known number of sample parts and a major scale for measuring the weight of an unknown number of parts to be counted, apparatus for indicating when the scales are zeroed. Circuitry is provided for automatically correcting the weight outputs from each scale for a limited amount of zero errors. A digital display indicates the corrected weight on one of the scales. When the corrected weight on any of the other scales is on zero, an indicator light associated with such scale is illuminated.