Device for describing arcs
AssigneeFiskars Inc.
InventorJames C. Boda
Life of this patent
Estimating the term…
Abstract
The present invention is directed to a device for describing arcs. The device includes a pair of legs connected at a pivot joint. A shoe is disposed at the end of one leg to support the device and maintain the center point of the arc while the device is used. An instrument is attached to the other leg so arcs can be formed as the device is rotated about the shoe. A rack and wheel are also connected to the legs to adjust the radius of the arc.
Claims21
A device for describing arcs on a surface, the device comprising:
- a pair of legs pivotably connected at one end by a pivot joint, each leg having a free end opposite the pivot joint;
- a rack affixed to one leg of the pair of legs and oriented to extend through an opening on the opposite leg, the rack having a plurality of teeth along at least one edge;
- a wheel having an outer periphery, the outer periphery rotatably disposed within the opening, the wheel including threads which cooperate with the plurality of teeth to move the rack and change the position of the legs with respect to each other when the wheel is rotated;
- an instrument holder attached to one of the legs, the instrument holder being configured to hold an instrument for describing arcs;
- and
- a shoe rotatably connected to the free end of the leg opposite the leg bearing the instrument holder, wherein the leg connected to the shoe can be rotated in the shoe to move the instrument in an arc about the shoe.
A compass to which an instrument may be attached to describe arcs of generally constant radius on a surface, the compass comprising:
- a first leg and a second leg connected together at one end by a pivot joint, the first leg being configured to hold an instrument which describes an arc on a surface as the first leg is rotated about the second leg, the pivot joint including a first hemisphere and a second hemisphere rotatably engaged;
- a rack affixed to one of the first or second legs and extending into cooperation with the opposite leg;
- and
- an adjustment mechanism mounted on the opposite leg and connected to the rack, wherein operating the adjustment mechanism moves the rack and pivots the first leg with respect to the second leg about the pivot joint.
A compass to which an instrument may be attached to describe arcs of generally constant radius on a surface, the compass comprising:
- a first leg having a first pivot end and a first distal end opposite the first pivot end;
- a second leg having a second pivot end and a second distal end opposite the second pivot end;
- a pivot joint connected to the first pivot end and the second pivot end, the pivot joint allowing the first and second legs to pivot towards and away from each other about the pivot joint;
- a rack affixed to one of the first or second legs and extending through an opening in the opposite leg, the rack having an arcuate form;
- a wheel having a ring with an outer periphery, and a central aperture, the ring having internal threads along the central aperture which cooperate with the rack proximate the opening to move the rack with respect to the opening and adjust the position of the first leg with respect to the second leg;
- an instrument for describing arcs;
- and
- a shoe having a generally flat bottom configured to support the compass on the surface, wherein the instrument and the shoe are connected to opposite legs and the shoe is rotatably attached to facilitate the describing of arcs.
Dependencies are inferred from the claim text.