Electric parking brake

An electric brake assembly for tensioning a brake cable attached to a brake such that tensioning of the brake cable affects application of the brake and untensioning of the brake cable affects release of the brake, the electric brake assembly comprising, in combination:

• an electric motor having an output shaft;
• a control module coupled to the electric motor for controlling the electric motor;
• a transmission coupling a threaded lead screw to the output shaft of the electric motor;
• a drive nut having a lead screw bore threadably receiving the lead screw therein and having a cable attachment for attaching the brake cable to the drive nut, the cable attachment having a central axis offset from a central axis of the lead screw, wherein the control module controls the electric motor such that rotation of the output shaft causes motion of the transmission and rotation of the lead screw, rotation of the lead screw causes linear motion of the drive nut, and linear motion of the drive nut causes tensioning and untensioning of the brake cable;
• and
• wherein the transmission comprises a gear train having a plurality of helical gears and the lead screw and the output shaft are substantially coaxial.

An electric brake assembly for tensioning a brake cable attached to a brake such that tensioning of the brake cable affects application of the brake and untensioning of the brake cable affects release of the brake, the electric brake assembly comprising, in combination:

• an electric motor having an output shaft;
• control module coupled to the electric motor for controlling the electric motor;
• a transmission coupling a the lead screw to the output shaft of the electric motor;
• a drive nut having a lead screw bore threadably receiving the lead screw therein and having a cable attachment for attaching thee brake cable to the drive nut the control module controls the electric motor such that the output shaft causes motion of the transmission and rotation of the lead screw, rotation of the lead screw causes linear motion of the drive nut, and linear motion of the drive nut causes tensioning and untensioning of the brake cable;
• a manual override device operatively connected to the lead screw, and wherein the manual override device selectively causes rotation of the lead screw, rotation of the lead screw causes linear motion of the drive nut, and linear motion of the drive nut causes tensioning and untensioning of the brake cable;
• wherein the manual override device includes a motion transmitting flexible core operably connected to the lead screw to selectively apply manual rotation to the lead screw.

An electric brake assembly for tensioning a brake cable attached to a brake such that tensioning of the brake cable affects application of the brake and untensioning of the brake cable affects release of the brake, the electric brake assembly comprising, in combination:

• an electric motor having an output shaft;
• a control module coupled to the electric motor for controlling the electric motor;
• a transmission coupling a threaded lead screw to the output shaft of the electric motor;
• an elongate guide shaft substantially parallel to and spaced apart from the lead screw;
• a drive nut having a lead screw bore threadably receiving the lead screw therein and a guide shaft bore slidingly receiving the elongate guide shaft therein, the drive nut also having a cable attachment attaching the brake cable to the drive nut, wherein the control module controls the electric motor such that rotation of the output shaft causes motion of the transmission and rotation of the lead screw, rotation of the lead screw causes linear motion of the drive nut along the lead screw and the guide shaft, and linear motion of the drive nut causes tensioning and untensioning of the brake cable;
• wherein the cable attachment is located between the lead screw bore and the guide shaft bore;
• wherein the cable attachment is located substantially midway between the lead screw bore and the guide shaft bore;
• and
• wherein a central axis of the brake cable near the lead screw is parallel to and offset from a central axis of the lead screw.

An electric brake assembly for tensioning a brake cable attached to a brake such that tensioning of the brake cable affects application of the brake and untensioning of the brake cable caused release of the brake, the electric brake assembly comprising, in combination:

• an electric motor having an output shaft;
• a control module coupled to the electric motor for controlling the electric motor;
• a transmission coupling a threaded lead screw to the output shaft of the electric motor, the transmission comprising a gear train having a plurality of helical gears, the lead screw and the output shaft being substantially coaxial;
• and
• a drive nut having a lead screw bore threadably receiving the lead screw therein and having a cable attachment for attaching the brake cable to the drive nut, wherein the control module controls the electric motor such that rotation of the output shaft causes motion of the transmission and rotation of the lead screw, rotation of the lead screw causes linear motion of the drive nut, and linear motion of the drive nut causes tensioning and untensioning of the brake cable.

An electric brake assembly for tensioning a brake cable attached to a brake such that tensioning of the brake cable affects application of the brake and untensioning of the brake cable affects release of the brake, the electric brake assembly comprising, in combination:

• an electric motor having an output shaft;
• a control module coupled to the electric motor for controlling the electric motor;
• a transmission coupling a threaded lead screw to the output shaft of the electric motor;
• a manual override device operatively connected to the lead screw;
• a drive nut having a lead screw bore threadably receiving the lead screw therein and having a cable attachment for attaching the brake cable to the drive nut, wherein the control module selectively controls the electric motor such that rotation of the output shaft causes motion of the transmission and rotation of the lead screw, rotation of the lead screw causes linear motion of the drive nut, and linear motion of the drive nut causes tensioning and untensioning of the brake cable, and wherein the manual override device selectively causes rotation of the lead screw, rotation of the lead screw causes linear motion of the drive nut, and linear motion of the drive nut causes tensioning and untensioning of the brake cable;
• and
• wherein the transmission includes a gear train, and wherein the manual override device includes an override gear operatively engaging the gear train to move the gear train upon rotation of the override gear and a motion transmitting cable operatively connected to the override gear to selectively rotate the override gear.

An electric brake assembly for tensioning a brake cable attached to a brake such that tensioning of the brake cable affects application of the brake and untensioning of the brake cable affects release of the brake, the electric brake assembly comprising, in combination:

• an electric motor having an output shaft;
• a control module coupled to the electric motor for controlling the electric motor;
• a transmission coupling a threaded lead screw to the output shaft of the electric motor;
• a drive nut having a lead screw bore threadably receiving the lead screw therein and having a cable attachment for attaching the brake cable to the drive nut, wherein the control module controls the electric motor such that rotation of the output shaft causes motion of the transmission and rotation of the lead screw, rotation of the lead screw causes linear motion of the drive nut, and linear motion of the drive nut causes tensioning and untensioning of the brake cable;
• and
• wherein the control module is adapted to stop the electric motor, when applying the brake, both upon reaching a predetermined cable tension and upon reaching a predetermined cable travel where the predetermined cable travel indicates a failure;
• and
• wherein the control module is adapted to stop the electric motor, when applying the brakes, when the predetermined cable tension is not reached within a predetermined period of time.

An electric brake assembly for tensioning a brake cable attached to a brake such that tensioning of the brake cable affects application of the brake and untensioning of the brake cable affects release of the brake, the electric brake assembly comprising, in combination:

• an electric motor having an output shaft;
• a control module coupled to the electric motor for controlling the electric motor;
• a transmission coupling a threaded lead screw to the output shaft of the electric motor;
• a drive nut having a lead screw bore threadably receiving the lead screw therein and having a cable attachment for attaching the brake cable to the drive nut, wherein the control module controls the electric motor such that rotation of the output shaft causes motion of the transmission and rotation of the lead screw, rotation of the lead screw causes linear motion of the drive nut, and linear motion of the drive nut causes tensioning and untensioning of the brake cable;
• and
• wherein the control module is adapted to stop the electric motor, when applying the brake, both upon reaching a predetermined cable tension and upon reaching a predetermined cable travel where the predetermined cable travel indicates a failure;
• and
• wherein the control module is adapted to stop the electric motor, when applying the brakes, when the predetermined cable travel is not reached within a predetermined period of time.