1. Field of the Invention
This invention relates to a safety seatbelt system, and more particularly to a seatbelt system by which a passenger is automatically caused to be protected upon taking a seat in a vehicle.
2. Prior Art
Various types of safety seatbelt for motor vehicle, airplane, etc., have been proposed and some of them have been actually used in the vehicle and so forth. However, since it is troublesome to put on a seatbelt, passengers are not willing to bother wearing the seatbelt even though a seatbelt system is provided in the vehicle. As a result, there have occurred a significant number of serious accidents which could have been avoided if the passengers wore seatbelts.
Japanese Patent Applications Laid-Open No. 16,329/73 and No. 49,128/73 disclose prior improved safety seatbelt systems, in which the system comprises: a seatbelt provided across a seat; a hook means fixed on the front edge of a door or in front of the seat, which hooks the middle portion of the seatbelt; a solenoid which releases the seatbelt from the hook means; and a circuit which operates the solenoid when the passenger takes his seat and closes the door, whereby the passenger is automatically protected by the seatbelt while driving the vehicle. As a result, the running safety of the vehicle is remarkably improved. In these seatbelt systems, however, since the solenoid operating circuit is controlled by a ignition switch, a seat switch, a shift lever switch, a door switch, etc., the systems have suffered from some drawbacks, such as that the seatbelt may come off from the passenger if he takes the seatbelt and has it hooked with the hooking means while driving the vehicle, and that it may cause confusion to the passenger in operating each one of the switches, particularly a shift-lever switch.