Adjustable energy absorbing device for use in a vehicle seat belt restraint system

Abstract

An apparatus (10) comprises vehicle seat belt webbing (26) which is extensible about a vehicle occupant. A first member (60) is connectable to the vehicle and a second member (90) is connected to the belt webbing (26). An energy absorbing mechanism (70) disposed between the first and second members (60, 90) dissipates energy transferred to the belt webbing (26) due to movement of a vehicle occupant against the belt webbing (26) in response to vehicle deceleration. The mechanism (70) includes a cutter block (75) disposed on one of the members (60, 90) for cutting into the material of the other of the members when an occupant presses against the belt webbing (26) in response to vehicle deceleration with a force above a predetermined magnitude. A first sensor (102) senses an occupant characteristic, such as the weight of the occupant. A second sensor (104) senses another occupant characteristic, such as the location of the occupant. A third sensor (106) senses a vehicle collision characteristic, such as the crash severity of the vehicle collision. A microcomputer (100) is responsive to at least one of the sensors (102, 104, 106) and generates a control signal (84) to actuate a motor (80) to adjust the position of the cutter block (75) relative to the other of the first and second members (60, 90) to vary the amount of cutting force, and thus energy, when applied over a distance to be dissipated by the energy absorbing mechanism (70).

Dependencies are inferred from the claim text.