GB1403597A - Motor vehicle comprising a safety device - Google Patents

Abstract

1403597 Vehicle collision sensors; safety devices NISSAN MOTOR CO Ltd 24 Nov 1972 [30 Nov 1971 28 April 1972] 54319/72 Headings B7B and B7H A motor vehicle collision sensor comprises a housing 52 having an elongate actuating member 58 slidable in a bore 56 therein and biased into a position extending externally of the housing, the actuating member 58 being arranged to be retracted into the housing upon a collision to actuate a safety device switch means. In a preferred embodiment, Fig. 1, a bumper 10 has a back plate 15 for securing a plate 31 of a piston-rod 25 movable within a shock absorbing cylinder 23 secured on the vehicle chassis. A resilient member 35, Fig. 2, of foam rubber is interposed between plates 31 and 15 and arranged to provide slight relative lateral movement of the plates 31, 15. The sensor 50 is mounted on the plate 31 and the actuating member 58 extends through apertures 76, 75 of the piston plate 31 and resilient member 35 respectively leaving a gap between the tip of the actuating member 58 and the back plate 15. On a collision the bumper 10 compresses resilient member 35 and member 58 is urged into the housing 52, Fig. 3, against spring 67 to disconnect contacts 62, 63 resulting in actuation of the vehicle safety device. Other embodiments are described in which the switch means comprises an electrically conductive leaf spring (85), Fig. 4 (not shown), which breaks a contact. In Fig. 5, switch means comprising two contacts (108), (110), Fig. 6 (not shown), one of which is magnetic, are hermetically sealed in a tube 92 which may contain inert gas or be evacuated, and are actuated by a permanent magnet 90 mounted on the actuating member 100. A cover (120), Fig. 7 (not shown), may enclose the actuating member 58. In another form of switch means, Fig. 8, the actuating member 138 is urged into housing 130 and piston 136 causes bellows 142 to expand pneumatically to move plate 144 away from fixed contact 152 against action of spring 146. In another switch means, Fig. 9 (not shown), the biasing means comprises a permanent or electromagnet (160). Fig. 10 illustrates a switch means comprising a tubular contact member 165 which shatters upon a collision from the end plate 60. The contact member may be glass coated with an electrically conductive material, or may be formed of carbon. A sensor 50 may be connected in series with an inertia switch (170), Fig. 13 (not shown). As shown in Fig. 14, the sensor 50 is opened upon a collision thus reducing to zero the force on weight 174 by electromagnet 182, so that weight 174 moves into contact with fixed contact 186. In another arrangement of inertia switch, Fig. 15, provision of electromagnet 206 connected in series with collision sensor 50 serves to reduce the magnitude of deceleration above which the inertia switch 170<SP>1</SP> is actuated at the time of collision.