Electromechanical parking brake system

Claim 1

Parking brake apparatus for operating the parking brake cable of a vehicle between non-tensioned brake-released and tensioned brake-engaged condition, respectively, comprising: (a) a housing (2) provided with a stationary main pivot shaft (4); (b) an annular cable track member (10) journalled on said pivot shaft, said cable track member being adapted for connection with one end of the parking brake cable; (c) drive means for alternately rotating said cable track member in opposite directions on said pivot shaft toward brake-engaged and brake-released positions relative to said housing, respectively, said drive means including: (1) a gear sector member (6) rotatably mounted on said pivot shaft; (2) reversible electric gear motor means (18) connected with said housing and including an output shaft having a driving pinion (20) in enmeshing engagement with said gear sector member; (3) pawl ratchet means normally connecting said gear sector member with said cable track member, said pawl and ratchet means including: (a) a ratchet (8) connected with one of said cable track and sector members; (b) a pawl (28) pivotally connected with the other of said members; and (c) spring means (30) normally biasing said pawl toward engagement with said ratchet; and (4) means (58) for alternately operating said motor means in opposite directions, respectively; and (d) means (34,62) for releasing said pawl from said ratchet, thereby to disconnect said cable track member from said drive means.