Patent · US Expired

Mass produced weight measuring system

US4140190A · kind A · utility

1Cited by
1References
25Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 26, 1977
Grant dateFeb 20, 1979
Priority date
Expiry dateSep 26, 1997

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01G23/32
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A mass produced weight measuring system includes an optical transducer for determining the displacement of a scale load support structure with respect to a scale frame. To facilitate mass fabrication an optical transducer is produced and both gratings adjusted for alignment as a subassembly unit independent of the scale frame and load support structure; the clearance between the grating planes is set and the movable grating temporarily fixed. Nonlinearities in scale load support deflection inherent with the scale linkage and providing components other than true vertical deflection are compensated by adjustment of the grating angle from a horizontal plane. During scale assembly, the scale frame and load support structure are placed in a main fixture, a transducer subassembly unit is selected, mounted to a subfixture and the grating planes referenced to scale assembly reference planes; then the transducer body is epoxy potted relative to the frame and the movable grating potted relative to the load support structure. The movable grating is then freed for movement relative to the transducer body.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.