US 5,615,485 AGranted

Instruments for drawing circles

AssigneeSafe-T Products, Inc.

InventorBruce Stoneberg

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Abstract

A device for forming circles on a drawing surface that includes, in part, a first rotatable member and a second rotatable member. The first rotatable member is substantially flat and includes an opening formed therein. The second rotatable member is resiliently disposed within the opening. A first means elevates the first rotatable member above the drawing surface to prevent smearing of lines on the surface. A second means elevates the second rotatable member above the drawing surface to prevent smearing of lines on the surface and to engage the surface for stabilizing the rotatable member over the surface. The second mechanism elevates the second rotatable member to approximately the same level as the first rotatable member. A plurality of holes are disposed in the first and second rotatable members. The holes accommodate a marking instrument used for forming the circles.

Claims12

Dependent claims

A device for forming circles with a marking instrument on a drawing surface comprising:

a first rotatable member having an opening formed therein, said first rotatable member being substantially flat, said first rotatable member having a plurality of holes disposed therein, said holes accommodating the marking instrument used for forming the circles;
a second rotatable member resiliently disposed within and coplanar with said opening, said second rotatable member having a plurality of holes disposed therein, said holes accommodating the marking instrument used for forming the circles;
combination means for elevating said second rotatable member above the drawing surface to prevent smearing of lines on the surface and for engaging the drawing surface to stabilize said second rotatable member over the surface,
said combination means including an aperture for locating said second rotatable means over a center point of a circle;
and
elevation means for spacing said first rotatable member above the drawing surface to prevent smearing of lines on the surface, said first rotatable member being elevated by said elevation means to approximately the same level as said second rotatable member.

3 more elements

Dependencies are inferred from the claim text.