US Patent 7418879 Latching inertial reel

A latching inertial reel temporarily holds an inertial reel in a locked position during a lateral acceleration and resetably holds the reel in a latched position as a result of a vertical acceleration. The reel is latched when a latching sensor experiences a vertical acceleration above a threshold. A latch holds the reel in the latched position after the acceleration reduces to prevent subsequent injury from secondary impacts of a vehicle occupant with objects or surfaces in the vehicle. The latch may later be reset to release the reel. A vehicle seat may further include a seat inertial reel to provide support to the seat during a crash. The seat inertial reel may be attached to a floor mounting point, or to an elevated mounting point.