Multi-function drafting instrument
OwnerAshfaq Ahmad Khaninventor
Life of this patent
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Abstract
A drafting instrument is disclosed that functions as a protractor, compass and ruler. The instrument is ideally suited for flat surfaces used for marking including: paper, dry erase board, chalkboard and drafting table. The instrument accommodates pencils, pens, chalks and markers and facilitates the drawings of arcs, circles and parallel lines. The instrument has a built-in protractor for measuring and drawing angles and multiple rulers for measuring distance and drawing straight lines. The preferred embodiment of the instrument is two-piece with an arm shaped main ruler and a single slide-ruler that freely slides in and out of the main-ruler. A place ring with thumbscrew is attached to the slide-ruler to hold a writing tool such as pencil, pen, chalk or marker.
Claims9
A drafting instrument providing compass, protractor and ruler functions, the instrument comprising:
- an arm shaped plate with the two arms joined on one side and extending outward on the other side (the arms from hereon termed as main-ruler body) including measurement indicia on the peripheral edges indicating distances in inches disposed thereon providing ruler functions,
- the arms of the main-ruler body having a slot on the inside surface, that a slide-ruler can be placed inside the slot, so that the slide-ruler is freely movable inside the main-ruler body,
- the slide-ruler body also including a plurality of measurement indicia indicating distances in centimeters on one edge and distances in inches on the other edge, the slide-ruler and the plurality of measurement indicia disposed thereon providing extra ruler functions,
- a quarter circle plate extending from one arm of the main ruler body including measurement indicia on the periphery indicating angles from 0 to 90 degree providing protractor functions,
- a pointed extrusion extending from the other arm of the main-ruler body permitting rotation of the slide-ruler about an axis during the compass functions,
- a place-ring with an aperture for thumbscrew attached on one side of the slide-ruler body providing a means for holding a writing tool such as a pencil, pen, chalk or a marker,
- a thumbscrew through the slide-ruler place-ring,
- a straight edge on the side where the two arms of the main-ruler are joined.
Dependencies are inferred from the claim text.