| 摘要 |
A fluid height sensor ( 10 ) includes a float ( 14 ) with an arm ( 20 ) fixed to a shaft ( 40 ) that extends into a cavity ( 30 ) in a housing ( 12 ). A switch assembly ( 32 ) in the housing includes a switch ( 50 ) formed by a largely stationary blade ( 52 ) and by a moveable switch blade ( 54 ) that moves forward (F) and rearward (R), respectively against and away from the stationary blade. The switch assembly also includes an activator ( 56 ) for snapping the switch blade as the shaft pivots back and forth. The activator ( 56 ) includes an activation blade ( 58 ) that is moved back and forth by the shaft, and a leaf spring ( 90 ) that extends in a loop between the outer ends of the activation blade and of the switch blade. The leaf spring compresses the switch blade by urging its outer end ( 74 ) towards its inner end ( 72 ), to cause the moveable blade to overshoot when it passes a center position in its forward and rearward movement. Only one end of the shaft projects into the housing cavity, so only one shaft end has to be sealed, the other arm ( 22 ) of the float being pivotally mounted on the outside of the housing.
|
