Horizon indicating device for marine sextant
Patent 4005938 Issued on February 1, 1977. Estimated Expiration Date: 
February 1, 1994. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
February 1, 1994. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 269486 1891641 InventorApplicationNo. 610866 filed on 09/05/1975US Classes:356/149, Gyroscope or pendulum stabilized optical element33/283, Having gravity responsive indicating means (e.g., pendulum, etc.)356/250Pendular suspension of optical element or reticleExaminersPrimary: Corbin, John K.Assistant: Rosenberger, Richard A. Attorney, Agent or FirmAbstractA horizon indicating device adapted to be mounted behind the horizon glass of a conventional marine sextant, comprising a wire indicator which is kept always in a horizontal position with two sets of pivotal axis forming a two dimensional universal support to cope with a rolling and pitching ship. The said device enables the sextant to function normally under poor visibility when the real horizon can not be seen. The self-illuminated wire indicator makes the sextant being able also to work during night time. | |
