Compact electromechanical linear actuator
AssigneeYoung & Franklin Inc.
InventorsWeijian Ma, Gabriel Silva
Life of this patent
Estimating the term…
Abstract
An electromechanical linear actuator that contains an electric servo motor mounted within a compact housing. A thermally conductive path of travel is provided to efficiently transfer heat out of the housing into the surrounding ambient. A further mechanism is provided for holding the stator windings of the motor in undisturbed contact with the inner wall of the housing when the motor is subjected to thermal stress. The motor is arranged to linearly position a push rod through means of a ball screw unit. The ball screw nut and the push rod ride on bearings within guideways to insure that the push rod tracks along a linear path of travel.
Claims9
An electromechanical actuator that includes:
- a housing having an opening passing therethrough that is centered about an axis;
- a brushless servo motor having a rotor assembly mounted inside said housing for rotation about said axis, said servo and a stator encircling the rotor assembly motor rotor containing a permanent magnet and said stator containing the motor windings;
- a tapered circular wedge tightly wedged between the stator and the inner wall of the housing to stationarily support the stator within the housing;
- a ball screw shaft aligned along the axis and having a tapered end that is tightly secured within a complementary tapered hole in said rotor assembly so that said shaft extends outwardly beyond one end of the rotor assembly;
- a ball screw nut mounted upon the extended end of said shaft so that said nut moves axially along the shaft as the shaft is rotated by said motor;
- a pushbar unit slidably contained within an end wall of said housing said pushbar unit being connected to said ball screw nut for movement along said axis, and
- control means connected to said motor for activating the motor to advance or retract the push bar a desired linear distance.
Dependencies are inferred from the claim text.