US Patent 7338128 Seat back lock

A seat back lock is included in a seat back of a vehicle. A knob is provided at the top of the seat back. A passenger in the vehicle pushes down the knob to cause the seat back to move from a standing position to a folding position on a seat. In the standing position, a striker extending from the body of the vehicle engages with a hook of the seat back lock. The seat back lock comprises a binding lever and a warning lever connected to the knob. Whenever the strike engages with the hook, the binding lever directly contacts the striker. If the striker incompletely engages with or disengages from the hook, the knob is pulled down by the warning lever to expose an indicator to permit the passenger to visually recognize it.