An Electromechanical Actuator

An electromechanical actuator for use in a hydraulic braking circuit of a vehicle comprising:

• an electric motor having a stator and a rotor, and a linear actuator that is located within the motor, in which:
• the stator is located within a housing having a first end and a second end, the rotor is located inside the housing and comprises an elongate rotor body having a bore passing from a first end of the body to a second end of the body, the bore being enlarged over a first portion of the body located towards the first end of the motor, and being of reduced size over a second portion of the body located towards the second end of the motor,
• the linear actuator comprising an elongate shaft that is located within the bore in the elongate rotor body, the shaft having a screw part at one end carrying an external thread that extends along a portion of the shaft that is located within the first portion of the bore in the rotor body, and a fixing part at the other end of the shaft that is a tightly located into the bore of the second portion of the elongate body to prevent radial movement of the shaft relative to the elongate body, the linear actuator further comprising a drive nut that surrounds the screw part of the shaft and is located at least in a retracted position inside the enlarged bore of the first portion of the rotor body, the drive nut having an internal thread and being connected to the screw part through a set of balls that engage the threads of the drive nut and screw part,
• and in which the fixing part of the shaft includes a tapering portion that engages a complimentary tapering portion of the bore in the second portion of the rotor body.