Electric actuator unit for a vehicle brake assembly

An electric actuator unit for a drum brake assembly comprising:

• an electric actuator unit for actuating the drum brake assembly to selectively move a pair of brake shoes of the drum brake assembly between a braking and a non-braking position, said electric actuator unit including a housing, a motor, a gear-set operatively coupled to be driven by said motor, a spindle nut operatively coupled to be rotationally driven by said gear-set, a pull rod operatively coupled to be translatorily driven by said spindle nut, and a brake shoe actuation link assembly directly coupled to an end of said pull rod so as to be actuated by said pull rod to thereby move the brake shoes between the braking and non-braking positions, said end of said pull rod being directly coupled to said brake shoe actuation link assembly by a first link member of said brake shoe actuation link assembly, said first link member having a first end pivotally connected to said end of said pull rod and a second end pivotally connected to a second link member of said brake shoe actuation link assembly;
• and
• a spring member disposed within said housing and around said pull rod so as to be operatively coupled to said pull rod for applying a follow up force to said pull rod when the brake shoes are in the braking position.

Apparatus adapted for use in a drum brake assembly comprising:

• an electric actuator unit including a housing, a motor, a gear-set operatively coupled to be driven by said motor, a spindle nut operatively coupled to be rotationally driven by said gear-set, a pull rod operatively coupled to be translatorily driven by said spindle nut, and a brake shoe actuation link assembly directly coupled to an end of said pull rod so as to be actuated by said pull rod to thereby move a pair of brake shoes of the drum brake assembly between braking and non-braking positions, said end of said pull rod being directly coupled to said brake shoe actuation link assembly;
• and
• means disposed around said pull rod for applying a follow up force to said pull rod when the brake shoes are in the braking position.