Patent ID: 7905441
Filing Date: 2011-03-15
Classification: B60R

Abstract:
1. A seat belt tensioner for a seat belt safety system, comprising: a seat belt spindle; a drive motor for driving the seat belt spindle; and a gear system connected to the drive motor, wherein the gear system is an automatic gear system that shifts automatically as a function of load, wherein the automatic gear system has a first force transmission path comprising a sliding clutch pawl engagable with a mating cam face of a disk cam for rotating the seat belt spindle by abutting against the mating cam face of the disk cam, wherein the automatic gear system is configured such that the sliding clutch pawl engages with an internal tooth of a connecting gearwheel of the automatic gear system when the sliding clutch pawl is engaged with the mating cam face of the disk cam in an engaging position by abutting against the mating cam face of the disk cam and disengages with the internal tooth of the connecting gearwheel when the sliding clutch pawl is disengaged from the mating cam face of the disk cam in a disengaging position by no longer abutting against the mating cam face of the disk cam, wherein the internal tooth of the connecting gearwheel is one of a plurality of internal teeth disposed within the connecting gearwheel forming a continuous toothing that encircles the disk cam, wherein the connecting gearwheel is different from the disk cam, wherein the automatic gear system comprises a spring placing the disk cam under a preload such that the disk cam is rotated into a blockade position as soon as the sliding clutch pawl passes from the engaging position into the disengaging position, and wherein the disk cam in the blockade position prevents the sliding clutch pawl from automatically passing again into the engaging position.