Dynamit Nobel Aktiengesellschaft

Egon Flach

Hellmut Bendler

Uwe Brede

Heinz Gawlick

Gerrit Scheiderer

Device for tensioning safety belts in vehicles in which one end of the safety belt is securable to the vehicle and the other end of the belt is securable to the tensioning device. The device includes a cylinder having a piston with a piston rod extending from one side of the piston out of the cylinder to which the safety belt is securable. The piston is provided with a recess receiving an electrically ignitable propellant charge cartridge such that upon ignition of the cartridge propellant gases are generated which flow into the cylinder at the piston rod side of the piston for causing the piston and piston rod to be displaced into the cylinder to effect a tensioning of the safety belt.

Device for tensioning safety belts in vehicles

A rotary power device for use in conjunction with tensioning mechanism of safety devices for the protection of passengers in vehicles and the like. The preferred embodiment disclosed is used for tensioning safety belts of a vehicle passenger restraint system in response to predetermined experienced deceleration such as occur in an accident situation. The rotary power device includes a rotary piston guided in a helically wound guide track such that the piston moves both rotatably and axially in response to compressed gas forces against a pressure face which extends in a plane containing the axis of rotation of the piston. A coupling bushing arrangement is interposed between the piston and the rotating shaft accommodating the safety belt, with axial movement of the piston with respect to the bushing and shaft, and with rotatable locking of the piston and shaft. In preferred embodiments, the rotary locking of the piston and the shaft is initiated only after the release of compressed gases causes an axial shifting of the bushing.

Growing community of inventors

Munich, Georgia

Egon Flach