Patent ID: 6739063
Filing Date: 2004-05-25
Classification: G01C,G10K

Abstract:
A combination compass comprising:a housing having a first end; a compass device mounted inside said housing; a top cover pivoted to the first end of said housing and being, capable of covering over said compass device, said top cover having a mouthpiece, a resonance chamber, an air passage connected between said mouthpiece and said resonance chamber, and a sound producing device disposed in said air passage and adapted to produce sound when a user blows air into said mouthpiece; said top cover comprises a first cover member, and a second cover member fastened to said first cover member and forming with said first cover member said mouthpiece, said air passage, said sound producing device, and said resonance chamber; and said top cover further comprises an aiming hole, the aiming hole of said top cover being formed of a first hole formed in said first cover member and a second hole formed in said second cover member, said first hole being formed of a first opening and a second opening, said first opening being relatively greater than said second opening, said second opening being a tapered opening gradually reducing from said first opening toward said second hole through said sound producing device.