| 摘要 |
An electronic counting scale, which may comprise a single relatively compact unit including all operable elements; or which may be based upon a modular construction including, firstly, an electronics unit which includes all basic electronic circuitry necessary to operation; and, secondly, a base unit. The base unit in the modular construction, includes the load cell, associated mechanical linkage, the weight receiving platform, and the like. It is adapted to directly receive the electronics unit, and includes connector means for enabling electrical interconnection with the electronics unit, and means for mechanically coupling the base unit to the electronics unit. The load cell is a parallelogram-type flexure frame, and is characterized by four strain gauges, which are located at the upper and lower surfaces of two vertically overlying flexure corners of the parallelogram. This arrangement-because of symmetry considerations-is uniquely free of second-order errors generated by offset loading. At the same time, the arrangement provides two corners completely free of strain gauges, providing sites which can be trimmed by filing or so forth to compensate for small symmetry errors present in the load cell as originally fabricated and assembled. Suitable electronic circuitry is provided to enable the counting function, including to enable updating of the stored weight per unit value for the articles in the sample group, and for auto-zero tracking to correct for drift in the circuitry.
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