Autoliv Development Ab

Christian Fischer

Martin Schmidt

Thomas Schmidt

Michael Pech

Matthias Steinberg

Tobias Voss

Simone Mesecke-Rischmann

Markus Furchert

A pyrotechnic tightening deviceof a safety belt unit having a force limiting unit, comprising—a gas generator, and—a piston, which is guided in a pipe and which closes a pressure chamber inside the pipe, wherein—a pressure can be applied to the pressure chamber by the gas generator, and—the piston can be driven by the pressure present in the pressure chamber to perform a tightening movement which can be transmitted by means of a force transmitting unit to the safety belt, wherein—the piston is formed in two parts consisting of a main body and a contact part arranged on the side of the main body facing the force transmitting unit, wherein—the contact part has a greater strength than the main body, wherein—the main body surrounds the contact part form fittingly at the end face facing the force transmitting device.

Pyrotechnic tightening device for a safety belt of a safety belt unit having a force-limiting unit

The invention relates to a belt tightener () with a mass body drive for a seat belt of a motor vehicle with a force-limiting device with&#x2014;a belt shaft () mounted rotatably in at least one opening () of a housing () that can be fastened fixedly to the vehicle, it being possible to wind up the seat belt on said shaft, &#x2014;a tightener drive wheel () connected non-rotatably to the belt shaft () and having recesses () distributed at regular intervals over the circumference, &#x2014;a chain forming the mass body drive made of loose mass bodies (), which are guided in a tightener tube () and can be driven by pressure application of the tightener tube (), wherein&#x2014;the belt shaft () can be driven in the winding direction of the seat belt by engagement of the driven mass bodies () in the recesses () of the tightener drive wheel (), wherein&#x2014;the mounting of the belt shaft () in the opening () of the housing () is designed to be flexible in the radial direction.

Belt tightener with a mass body

A seatbelt tensioner for a seat belt retractor, having a pipe () with a tensioner drive wheel, a gas generator (), a piston (), and at least one mass body (). The mass body () is drivable by gas from the gas generator () acting on the piston () between the gas generator () and a mass body (). The mass body drives the tensioner drive wheel. The pipe () has a receiving section () with a first inner diameter (), in which the piston () in its initial state is arranged with an initial-state outer diameter (). The pipe () has a guide section () which adjoins the receiving section () and which has a second inner diameter (). The second inner diameter () is smaller than the first inner diameter () and smaller than the initial-state outer diameter () of the piston ().

Retractor pretensioner with piston rest area

A piston for a pretensioner device () for a motor vehicle seat belt system of a type having a gas generator () with the piston () guided in a tube () that closes a pressure space () in the tube (). The pressure space () can be pressurized by the gas generator (), driving the piston () to undergo pretensioning operation transmitted to the seat belt system by a force transmission means. The piston has a dome shaped front side adapted to engage a force transmission element and a skirt forming a sealing lip oriented toward the pressure space. At least one slot is formed in the outer surface of the piston extending axially from the sealing lip. The slot can be enlarged by the material erosion caused by the pressure and/or pressure conditions in the pressure space produced by gas from the gas generator.

Pretensioner device for a seat belt

A tensioning device () for a seat belt, in particular in a motor vehicle, having a gas generator () and a piston () guided in a tube () that closes a pressure space () in the tube (), whereas the pressure space () can be pressurized by the gas generator (), as a result of which the piston () can be driven to perform a tensioning operation which can be transmitted to the seat belt by means of the force transmission means. The piston () having a closed or constricted opening (), and the opening () can be enlarged and/or opened by the material erosion caused by the pressure and/or pressure conditions in the pressure space ().

Tensioning device for a safety belt

A pretensioning device () for a safety belt, of a motor vehicle, having a gas generator (), a piston () guided in a tube (), which closes a pressure area () in the tube () that is pressurized by the gas generator () whereupon the piston () is able to move in a pretensioning movement which is able to be conveyed to the safety belt by means of an inertia body () resting on a front face () of the piston (). The piston () forms a pass-through opening () releasable upon exceeding of a predetermined pressure and a recess () is provided in the front face () with an inertia body () resting thereon, so that a flow connection is created from the pass-through opening () to the area () located behind the piston () in the direction of the pretensioning movement (S).

Growing community of inventors

Hamburg, Germany

Christian Fischer