Abstract An instrument comprising two or more elongated flexible strips of plastic having magnetic properties such that when the strips are in a first position relative to one another, they overlap their full widths and cling together to form a multiple thickness assembly; and in a second position with the ends of one strip reversed relative to the other, they overlap only half widths. In the first position, the strips form a laminated flexible drafting spline which adheres to a sheet-steel-faced board underlying a sheet of drawing paper. There are measurement graduations and indicia along the edges and the two overlapping strips can be slipped endwise with respect to one another to form an extensible measuring tape for measuring distances along curved lines. Strips with logarithmic graduations can be used in said second position to form a slide rule.
Inventors
👤 C Mehl
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-10-29 23:12
CPC Classifications
B; B43; B43L; B43L13/00; B43L13/20; B43L13/22
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
197 words
An engineering instrument comprising a pair of elongated strips of magnetic elastomeric material, said strips being rectangular in cross section, and said material being polarized so that diagonally opposite corners of each of said strips have the same polarity, and opposite edges of each of the four sides of each strip are of opposite polarity, whereby said strips cling together side-by-side by mutual attraction; said strips overlapping one another for their full widths when placed together with their respective ends in one order, and said strips overlapping half their respective widths when one strip is turned end-for-end from said one order; said strips being slidable lengthwise with respect to one another when adhered together in overlapping relationship; and graduations and indicia provided on one side of each of said strips along the length thereof, the graduations and indicia of one strip being registrable with the graduations and indicia of the other strip when said strips overlap for half their respective widths to provide a reading that is a function of the relative lengthwise position of one strip with respect to the other; said strips being firmly held together by magnetic attraction so that accidental displacement is resisted.
Claim 2
Dependent Claim
197 words
An engineering instrument comprising a pair of elongated strips of magnetic elastomeric material, said strips being rectangular in cross section, and said material being polarized so that diagonally opposite corners of each of said strips have the same polarity, and opposite edges of each of the four sides of each strip are of opposite polarity, whereby said strips cling together side-by-side by mutual attraction; said strips overlapping one another for their full widths when placed together with their respective ends in one order, and said strips overlapping half their respective widths when one strip is turned end-for-end from said one order; said strips being slidable lengthwise with respect to one another when adhered together in overlapping relationship; and graduations and indicia provided on one side of each of said strips along the length thereof, the graduations and indicia of one strip being registrable with the graduations and indicia of the other strip when said strips overlap for half their respective widths to provide a reading that is a function of the relative lengthwise position of one strip with respect to the other; said strips being firmly held together by magnetic attraction so that accidental displacement is resisted.