Patent · US Expired

Ruler with magnifying cursor

US4757616A · kind A · utility

52Cited by
3References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 26, 1987
Grant dateJul 19, 1988
Priority date
Expiry dateOct 26, 2007

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01B3/04
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A ruler for use in the measurement of distances on a flat surface is disclosed herein, having an elongated base with raised edge marginal regions defining a T-shaped recess therebetween. A first edge marginal region displays a plurality of analog measurement increments in the form of transverse marked lines while numerical indicia associated with each line increment is carried at the bottom of the recess. A cursor having an inverted T-shaped portion is slidably engaged with the base T-shaped recess. The cursor further includes a guide rail on one side frictionally engaged with a track provided on a second one of the edge marginal regions while cantilevered finger having an index line thereon projects over the first edge marginal region for selected registration with the end of an object being measured. An enlarged semicircular magnifier is carried on the cursor midway between its opposite sides for visually enlarging numerical indicia associated with a measurement line mark selected by registration of the index line therewith.

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