Seat belt pretensioner

An apparatus for tensioning a vehicle seat belt and tightening the seat belt against a vehicle occupant, said apparatus comprising:

• a buckle connectable with a tongue of a seat belt;
• an anchor connectable with a part of a vehicle;
• a housing fixed to said anchor, said housing including a first wall and a longitudinal axis;
• a second wall in said housing and cooperating with said first wall to define opposite ends of an expansible chamber, said second wall being movable relative to said first wall in a first direction along the axis;
• a connector fixed to said second wall and to said buckle, said connector extending through said first wall;
• and
• actuatable means carried by one of said first and second walls and in fluid communication with the expansible chamber for applying, upon actuation, a fluid pressure force against said first and second walls to expand said expansible chamber for moving said buckle in the first direction along the axis to tension the seat belt and tighten the seat belt against the occupant;
• said second wall being connected with said buckle by said connector, said second wall being movable relative to said housing and said first wall in response to actuation of said actuatable means;
• said actuatable means being fixed to said second wall, said actuatable means being movable with said second wall relative to said first wall.

An apparatus for tensioning a vehicle seat belt and tightening the seat belt against a vehicle occupant, said apparatus comprising:

• a buckle connectable with a tongue of a seat belt;
• an anchor connectable with a part of a vehicle;
• a housing fixed to one of said buckle and said anchor, said housing including a first wall and having a rectangular inner periphery taken in a plane extending normal to a longitudinal axis of said housing;
• a second wall in said housing and cooperating with said first wall to define opposite ends of an expansible chamber, one of said first and second walls being movable relative to the other of said first and second walls, said second wall having a rectangular outer periphery taken in the plane;
• a connector fixed to said second wall and to one of said buckle and said anchor, said connector extending through said first wall;
• and
• actuatable means in fluid communication with the expansible chamber for applying, upon actuation, a fluid pressure force against said first and second walls to expand said expansible chamber for tensioning the seat belt and tightening the seat belt against the occupant.

An apparatus for tensioning the seat belt and tightening the seat belt against a vehicle occupant, said apparatus comprising:

• a buckle connectable with a tongue of a seat belt;
• an anchor connectable with a part of a vehicle;
• a housing fixed to said buckle, said housing including a first wall;
• a second wall fixed to said anchor by a connector, said second wall located in said housing opposite said first wall, said first and second walls being relatively movable, said first and second walls cooperating with said housing to define an expansible chamber, said connector extending through said first wall;
• actuatable means in fluid communication with the expansible chamber for applying, upon actuation, a fluid pressure force against said first and second walls to expand the expansible chamber for tensioning the seat belt and tightening the seat belt against a vehicle occupant;
• each of said housing and said second wall having a rectangular periphery taken in a plane extending normal to a longitudinal axis of said housing.

An apparatus for tensioning the seat belt and tightening the seat belt against a vehicle occupant, said apparatus comprising:

• a buckle connectable with a tongue of a seat belt;
• an anchor connectable with a part of a vehicle;
• a housing fixed to said anchor, said housing including a first wall;
• a second wall fixed to said buckle by a connector, said second wall located in said housing opposite said first wall, said first and second walls and said housing defining an expansible chamber, said connector extending through said first wall;
• said housing and said second wall having respective rectangular peripheries taken in a plane extending normal to a longitudinal axis of said housing;
• and
• actuatable means in fluid communication with the expansible chamber for applying, upon actuation, a fluid pressure force against said first and second walls to expand said expansible chamber and tension the seat belt and tighten the seat belt against a vehicle occupant.