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US 4,010,674 AGranted
Speed responsive systems
AssigneeAssociated Engineering Limited
InventorsJohn Noddings, Norman Hunt
Life of this patent
Estimating the term…
Abstract
An actuator device includes a chamber partly bounded by a movable wall and connected to atmosphere through a permanently open orifice and an electromagnetic valve which is maintained in a closed position when de-energized and which controls the connection to said chamber of a volume of gas at other than atmospheric pressure when said valve is open.
Claims6
An actuator device comprising:
- a chamber having a relatively fixed wall and a relatively movable wall interconnected by a bellows,
- a spring within said chamber to urge said bellows to an extended position,
- a permanently open orifce through which said chamber is connected to atmosphere,
- a cavity provided in said relatively fixed wall outside of said bellows,
- an electromagnetic valve housed in said cavity and including a solenoid winding surrounding an armature movable in a direction transverse to the direction of movement of said bellows,
- an aperture in said cavity which is closed by one end of the armature of said electromagnetic valve when said solenoid winding is de-energised, and which is opened by retraction of said armature from said aperture when said solenoid winding is energised to enable the connection to said chamber of a volume of gas at subatmospheric pressure to cause said bellows to contract against the force of said spring, and resilient means acting on the other end of said armature for urging said armature to close said aperture when said solenoid is de-energised.
3 more elements
Dependencies are inferred from the claim text.