| 摘要 |
<p>763,475. Automatic speed control systems. TEDDINGTON AIRCRAFT CONTROLS, Ltd., [formerly TEDDINGTON CONTROLS, Ltd.]. Feb. 9, 1955 [Feb. 9, 1954], No. 3825/54. Class 38 (4). A D.C. series motor coupled through reduction gearing to operate, for example, a hot air valve in an aircraft pressurization system, has an armature 6, Fig. 5, and is run in one direction or the other by operation of a change-over switch 1 to connect the appropriate field winding 3 through a brake winding 5. A switch 12 is placed in the position shown for fast running, but is changed over to introduce a series resistor 9 shunted by centrifugal governor-controlled contacts 7 when constant slower speed running is desired. Under the latter conditions an electromagnetic clutch 11 is energized to couple the centrifugal governor to the motor and the clutch winding also acts as a diverter to assist in the reduction of speed. Motor travel in either direction is limited by switches 2 co-operating with indicator lamps 4.</p> |
