GB1360360A - Operation recorder for motor vehicle safety device - Google Patents

Abstract

1360360 Crash restraint bag NISSAN MOTOR CO Ltd 12 Dec 1972 [9 Feb 1972] 57264/72 Heading B7B The correct operation of a crash restraint bag is recorded by a memory device 15 fed with signals S4 by a coincidence circuit 13, fed with signals S2 by a collision sensor 10 through a gating circuit 11 and with signals S3 by a sensor 14. The sensor 10 is responsive to a collision condition of a vehicle, e.g. it may be a mass of magnetic material normally abutting a magnet but moved, due to rapid deceleration upon a collision, to engage two contacts. The gating circuit 11 generates a signal S2 of a predetermined time duration of the order of 10 to 100 milliseconds, i.e. longer than the time required for the crash bag to be actuated. The sensor includes comparators 32, 33 connected at points (a) and (b) respectively. When the voltages at points (a) and (b) become 12 and zero respectively, due to destruction of detonation element 21, the comparators 32 produce outputs fed to a NOR gate which applies a true "1" signal S3 to an AND gate. If a true "1" signal is also applied to the AND gate by the gating circuit 11 a true "1" signal is applied to a transistor 41 to burn out an electric fuse 40, thus indicating a malfunction, i.e. operation of the bag prior to collision or at a time greater than a predetermined time after a collision. If on the other hand, correct operation ensues, the signals at the AND gate are not synchronized such that the transistor 41 is not energized. The sensor 14 may alternatively be a pneumatically controlled switch opened and closed in response to pressure in a container for storing pressurized gas, a conductive wire adapted to be broken upon actuation of the safety device, or an electric or mechanical switch capable of sensing expansion of the gas bag.