Patent GB-1503493-A (GB)
Title: Two-part buckles for vehicle seat belt systems
IPC: A44B11/25
Filed: 1974-05-02
Abstract: 1503493 Buckles KANGOL MAGNET Ltd 1 May 1975 [2 May 1974] 19425/74 Heading E2A The specification discloses a number of different embodiments of a buckle 10 for a vehicle seat belt system the buckle 10 comprising a socket portion 20 including a frame member 24 within which a tongue portion 12 can be releasably latched; the socket portion 20 comprises a latch plate 28 with a deformed latch portion 30 for latching engagement with an aperture in the tongue portions 12, the latch plate 28 being slidably guided for movement between latching and releasing positions by means of side portion 32 received in gaps 34 in side walls 27 of the frame member 24. In the embodiment of Figs. 1-3 the frame member 24 having a floor 25 and side walls 27 forms a socket for receiving the tongue portion. The latch portion 30 of the latch plate 28 projects through an aperture in the floor 25. The latch plate 28 has permanently secured thereto a release member 36 and spring means act between a housing 22 and latch plate 28 to urge the latter into its latching position-as illustrated. The spring means comprise a pair of leaf springs 38 but it could comprise a barrel or conical coil spring. The housing 22 comprises an upper case 40 and a lower case 42 both of moulded acrylonitrile butadiene styrene and secured by ultrasonic welding. The frame member 24 is secured to a flexible cable 46 having an apertured end fitting by which it can be anchored to the vehicle floor. To facilitate removal of the tongue portion 12 when the release member 36 is manually depressed to withdraw the latch portion 30 from the aperture in the tongue portion 12, the frame member 24 mounts a pair of ejection springs 52 and an ejection member 54 in the form of a flat U-shaped moulding or pressing. The limbs 55 of the member 54 are guided in the frame member 24 as are a pair of pins 56 received in the springs 52. In the embodiment of Figs. 4, 5 (not shown) the latch plate (28) is urged to its latching position by a spring steel rectangular leaf spring (102) acting between the side walls (27) of the frame member (24) and the release member (136). In this embodiment only one ejection spring (152) is provided. The frame member is connected to a flexible metal cable (146) by a thimble (144). In the embodiment of Figs. 6, 7 the release member 236 is provided with a ramp portion 237 for engagement with a wedgeshaped cam portion (208) of a release element 204 pivoted on a pin 202 extending beween housing cases 240, 242 at right engles to the plane of movement of tongue portion 12. To release the buckle portion a push member 205 accessible through mating recesses 210, 211 in cases 240, 242 is pressed to pivot release element 204 against a tension spring 209 to thereby move release member 236 by the interaction of portions 237, (208). In the embodiment of Fig. 8 (not shown) a release element (304) for engagement with a ramp portion (237) of a release member (306) is guided in the upper housing case (340) for sliding movement parallel to the direction of insertion of the tongue portion (12). the release element being biassed by a pair of springs (309).  In the embodiment of Fig. 9 (not shown) the frame member (24) connects with a vehicle anchorage by means of a length of webbing (404) instead of a cable, the frame member (24) being secured to an end fitting (402) slotted to receive the webbing (404). Alternatively a bracket can be secured to the frame member to rigidly mount the socket portion in the vehicle, and the fitting or bracket may be made integral with the frame member. The buckle of Figs. 10, 11 (not shown) incorporates a microswitch (502) between the floor (525) of the frame member (524) and the lower case (42) which microswitch indicates the presence or absence of the tongue portion (12) within the socket portion. The microswitch is actuated via a lever (504) engaged by a lip (503) on the ejection member (554) when the tongue portion (12) is inserted in the socket portion.