WOOD COMPASS Russian patent published in 1998 - IPC

FIELD: forestry production. SUBSTANCE: wood compass has compass box with compass numbering and cylindrical threaded hole in center. Compass box is covered with protective glass. Numbered dial is hinge-connected to compass box coaxially with the latter. Upper and lower bushes-supports are positioned coaxially in vertical plane. Axle is installed with its sharpened ends in bushes-supports for easy rotation under effect of magnetic orientation of magnetic pointer secured on axle rigidly. Screw with central through hole is positioned above lower bush-support for passing the axle with clearance and groove underneath on external surface which forms pocket of volume V1 together with surface of compass box threaded hole. Antifriction liquid in volume V2 which is less than volume V1 is filled-in above upper edge of lower bush-support. Diopters are made detachable and coupled with verniers. EFFECT: improved design. 3 dwg