Belt tightener for seat belts in vehicles

A belt tightener for seat belts in vehicles, said belt tightener including a device for moving the belt buckle in a belt-tightening sense and for locking the belt buckle at the end of the tightening movement, said device being activated by a vehicle-sensitive system which activates said belt tightener in response to an acceleration or deceleration in excess of predetermined critical values, characterized in that

• the belt buckle is carried by a bracket which is guided for a longitudinal displacement in a housing, said guide housing being connected to part of the vehicle and being provided with means which permit a pull-in movement of the bracket but block its movement in the opposite direction,
• the belt buckle being operatively coupled to one end of a tensile element, which at its other end is connected to an energy storage device, said energy storage device including a prestressed spring and being adapted in case of relaxation to impart a pull-in movement via the tensile element to the belt buckle, and
• a locking device for retaining said spring in its prestressed position, said locking device being controlled by the vehicle-sensitive system and said tensile member being connected to a tie rod which is slidable within a spring housing and is held in locked configuration by a toggle joint system operably coupled to and activated by said vehicle sensitive system, said prestressed spring being held in compression within said spring housing by said tie rod when in the locked configuration yet exerting a pull-in force on said tensile element when said locking device is disengaged in response to accelerations in excess of a predetermined value to cause a tightening of the seat belt, yet said seat belt buckle will be blocked from movement in the opposite direction.

A belt tightener for seat belts in vehicles, said belt tightener including a device for moving the belt buckle in a belt-tightening sense and for locking the belt buckle at the end of the tightening movement, said device being activated by a vehicle-sensitive system which activates said belt tightener in response to an acceleration or deceleration in excess of predetermined critical values, characterized in that

• the belt buckle is carried by a bracket which is guided for a longitudinal displacement in a housing, said guide housing being connected to part of th vehicle and being provided with means which permit a pull-in movement of the bracket and block its movement in the opposite direction,
• the belt buckle being operatively coupled to one end of a tensile element which, at its other end, is connected to an energy storage device, said energy storage device including a prestressed spring and being adapted in case of relaxation to impart a pull-in movement via the tensile element to the belt buckle, said tensile member comprising a flexible rope wrapped at least partially around a pulley member and being coupled to said belt buckle, and
• a locking device for retaining said spring in its prestressed position said locking device being controlled by the vehicle-sensitive system in such a manner that said locking device will be disengaged in response to accelerations in excess of a predetermined value to cause a tightening of the seat belt, yet said seat belt buckle will be blocked against movement in the opposite direction.

A belt tightener for seat belts in vehicles, said belt tightener including a device for moving the belt buckle in a belt-tightening sense and for locking the belt buckle at the end of the tightening movement, said device being activated by a vehicle-sensitive system which activates said belt tightener in response to an acceleration or deceleration in excess of predetermined critical values, characterized in that

• the belt buckle is carried by a bracket which is guided for a longitudinal displacement in a housing, said guide housing being connected to part of the vehicle and being provided with means which permit a pull-in movement of the bracket and block its movement in the opposite direction,
• the belt buckle being operatively coupled to one end of a tensile element which, at its other end, it connected to an energy storage device, said energy storage device including a prestressed spring within a spring housing and being adapted in case of relaxation to impart a pull-in movement via the tensile element to the belt buckle, said guide housing and said spring housing being secured to a seat in the vehicle, with a seat tie rod coupled between the seat and the vehicle
• a locking device for retaining said spring in its prestressed postion, said locking device being controlled by the vehicle-sensitive system in such a manner that said locking device will be disengaged in response to accelerations in excess of a predetermined value, and
• a locking lever coupled to said guide housing for lockable engagement with said seat tie rod in response to a tension force exerted on the spring housing such that guide housing in directly connected to said seat tie rod when said belt tightener is activated, regardless of the position of the seat.

A belt tightener for seat belts in vehicles, said belt tightener including a device for moving the belt buckle in a belt-tightening sense and for locking the belt buckle at the end of the tightening movement, said device being activated by a vehicle-sensitive system which activates said belt tightener in response to an acceleration or deceleration in excess of predetermined critical values, characterized in that

• the belt buckle is carried by a bracket which is guided for a longitudinal displacement in a housing, said guide housing being connected to part of the vehicle and being provided with means which permit a pull-in movement of the bracket but block its movement in the opposite direction,
• said bracket comprising a rail which includes a row of holes and is guided for slidable movement by guide members in the guide housing, said guide members supporting the rail on opposite sides, and said holes in said bracket being adapted to receive a locking member to prevent a pull-out movement in said opposite direction,
• the belt buckle being operatively coupled to one end of a tensile element, which at its other end is connected to an energy storage device, said energy storage device including a prestressed spring and being adapted in case of relaxation to impart a pull-in movement via the tensile element to the belt buckle, and
• a locking device for retaining said spring in its prestressed position, said locking device being controlled by the vehicle-sensitive system in such a manner that said locking device will be deisengaged in response to accelerations in excess of a predetermined value to cause a tightening of the seat belt buckle yet said belt buckle will be blocked from movement in the opposite direction.

A belt tightener for seat belt in vehicles, comprising a device for moving the belt buckle in a belt-tightening sense and for locking the belt buckle at the end of the tightening movement, said device being activated by a vehicle-sensitive system in response to an acceleration or deceleration in excess of predeetermined critical values, and the belt buckle being secured to a tightening lever, which is pivoted to a plate that is fixed to the vehicle, said tightening lever is biased by a spring in a tightening sense and is held in an inactive position by a locking member which, in response to a critical acceleration or deceleration, unlocks the tightening lever, which is thence blocked by a ratchet in its tightening end position relative to the plate which is fixed to the vehicle, and the ratchet member cooperates with a pawl lever that is pivotally attached to the tightening lever, characterized in that said pawl lever is guided in a slot of the plate which is fixed to the vehicle with at least one edge of the slot being formed with the ratchet teeth, and wherein said vehicle sensitive system comprises a sensor lever movably mounted at its lower end to said plate, said sensor lever comprising an inverted gravity pendulum which, when deflected from its rest position due to an acceleration or deceleration in excess of the predetermined values, deflects a lever blocking the tightening lever, thereby releasing the tightening lever.