Integrated magnetostrictive linear displacement transducer and limit switch for an actuator

A position sensor and limit switch apparatus for an actuator having a cylinder and a piston with at least one magnetized portion reciprocatingly disposed within the cylinder, the apparatus comprising:

• an elongate housing aligned parallel with the cylinder;
• a magnetostrictive linear displacement transducer disposed within the housing for sensing the position of said at least one magnetized portion;
• and
• a limit switch which operatively interrupts actuation of the piston upon said at least one magnetized portion reaching a first limit position, said limit switch being responsive to the transducer.

In combination, a hydraulic actuator for a marine craft, and a position sensor and limit switch apparatus therefor, the hydraulic actuator having a trim cylinder and a piston with at least one magnetized portion reciprocatingly disposed within the trim cylinder, the apparatus comprising:

• an elongate housing aligned parallel with the cylinder;
• a magnetostrictive linear displacement transducer disposed within the housing for sensing the position of said at least one magnetized portion;
• and
• a limit switch which operatively interrupts actuation of the piston upon said at least one magnetized portion reaching a trim-out limit position, said limit switch being responsive to the transducer, the trim-out limit position being a maximum extended position of the piston considered safe to operate the marine craft under power.