James F Angus

US Patent:

40525970, Oct 4, 1977

Filed:

Jul 9, 1976

Appl. No.:

5/704044

Inventors:

James W. Angus - Nashua NH

Assignee:

Sun Chemical Corporation - New York NY

International Classification:

G06M 118
G01L 712

US Classification:

235 92C

Abstract:

An auxiliary force-applying mechanism is connected to a counter type altimeter for applying a supplemental force to rotate its counter mechanism at the time a Geneva type mechanism advances a second drum by one indicator position. The force applied to the drum mechanism is approximately equal to the additional force required to advance the second drum through the Geneva mechanism so that a relatively constant load is applied to the altimeter driving mechanism such as an aneroid capsule. In a second embodiment, a constant auxiliary force is applied to the altimeter drum and this relatively constant auxiliary force is relieved during the time that the Geneva mechanism advances a second drum by one drum position so that a relatively constant force is applied to the aneroid capsule. An electronic circuit is provided for actuating the auxiliary force-applying mechanism and contains photosensing circuit means which actuates at the time that the Geneva mechanism becomes operative for moving a second drum, and the photosensing elements are arranged relative to slots in a drum rim.