Geometrical instruments – Straightedge type – Base attached
Patent
1982-02-04
1984-08-28
Little, Willis
Geometrical instruments
Straightedge type
Base attached
33448, B43L 500
Patent
active
044675283
ABSTRACT:
A ruler, especially a parallel ruler having a parallel guidance system comprising a cord (6) extending between four points (A,B,C&D) and crossing itself diagonally in a corner to corner-fashion in the central portion of the ruler, which ruler consists of two flexible parts, a ruler body (1) and a finger rail (2) being in slidable engagement by dovetailing (9) and having clamping devices in both ends in the form of a tapped sleeve (3) and a screw (4) in holes (7), whereby, upon imparting upon the two parts a differently curved shape, the two parts may be clamped together showing a rise of the arch of the ruler, so that the ruler will more easily be pulled over the surface of the drawing-board.
The central portion of the finger rail (2) may be removed, whereby the cord (6) may cross itself in this cut away-area (8). Such cord will not hamper the draftsman and will still be easily accessible for check and repair.
REFERENCES:
patent: 3106783 (1963-10-01), Justis
patent: 3283410 (1966-11-01), Truhon
patent: 3374546 (1968-03-01), Justis, Sr.
patent: 3425128 (1969-02-01), Cooper
LandOfFree
Parallel ruler does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Parallel ruler, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Parallel ruler will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-870717