Linear drive for vehicle restraining systems
AssigneeTRW Repa GmbH
InventorArtur Fohl
Life of this patent
Estimating the term…
Abstract
In a linear drive for belt pretensioner in vehicle restraining systems a piston/cylinder unit (10) is used, the piston of which is subjected to pressure by the gases generated by a pyrotechnical gas generator (26). A pulling cable (12) is connected to the piston (24), said connection not being direct but with interposition of a damping means (32) which in the phase of the pressure rise of the gases limits the force exerted on the pulling cable (12) and allows said force to increase smoothly and is effective during a substantial fraction of the initial phase of the piston movement in which the gas pressure (D) generated by the generator (26) rises.
Claims18
A linear drive for a belt pretensioner in a vehicle safety belt system, comprising:
- a pyrotechnical gas generator;
- a piston/cylinder unit which is activatable by the gases generated by said generator;
- and
- a pulling cable being connected to said piston of said piston/cylinder unit in a manner to establish a flow path of force between said piston and said cable which comprises a deformable damping means dimensioned to limit the force exerted by said piston on said cable in a phase of pressure rise of gas released by said gas generator and to allow said force to rise continuously, said damping means being effective during an entire initial phase of piston movement in which the gas pressure provided by the gas generator rises.
A pretensioner drive for a vehicle safety belt system, said drive comprising:
- a cylinder;
- a piston located within said cylinder and movable relative to said cylinder through a pretensioning stroke;
- gas source means for providing a gas pressure to move said piston relative to said cylinder in response to sudden vehicle deceleration;
- cable means for transmitting a pulling force from said piston to a belt tensioning device;
- and
- damping means interconnecting said piston and said cable means for limiting the force exerted by the piston on said cable means during an entire initial period as the gas pressure increases and for permitting said piston to move relative to said cable during the entire initial period and thereafter to move said cable.
Dependencies are inferred from the claim text.