VEHICLE DOOR LATCHING

Abstract: An arrangement in which an external handle (2) of a door (4) of a vehicle is connected to a latch (6) of the door for releasing the latch from a keeper thereby to allow the door to open, the handle and the latch being separated by a direct distance (d), wherein a cable is connected (12) at one of its ends to the handle and at its other end to the latch to effect said releasing, wherein the cable follows a path of length (D) that is curved and extends between the handle and the latch, and wherein the ratio D/d>/= 1.1.

Description: Vehicle Door Latchins This invention relates to the latching of the door of a vehicle, and in particular to the provision of a latching arrangement employing a safety cable that is designed to prevent the door opening upon impact such as in an accident. A vehicle door is provided with a latch for engagement with a keeper mounted on a door post of the frame of the vehicle, and with an internal and external handle for operating the latch. Typically, the internal door handle is located about 600 mm away from the latch. this distance being related to the length of the vehicle door. It is known to use a rod to interconnect the handle with the latch to open the door. However, in the event of an impact on the door, such as can occur in an accident, the door may buckle in such a way and to such an extent so as to operate the latch and thus open the door. It is also known to interconnect the internal door handle and latch by means of a Bowden cable, which has the advantage over a rod connection because, due to its flexibility, it can be displaced from its normal routing and yet still not activate the latch. Because of the presence of other components within the door and the need, usually to allow window glass to retract into the door, the route of the rod or cable between the handle and latch mechanisms can deviate significantly from a straight line. The separation between an external handle of a vehicle door and the latch, however, may only be between about 50 and 100 mm, since usually there are no intervening components that have to be avoided. The two mechanisms may be interconnected by a rod or a Bowden cable that is arranged to be as short as possible, in order to minimise the cost, and thus extends in a straight line directly from the external handle to the latch. Even with this shorter arrangement, however, it has been found that the latch can be released due to deflection of the rod or cable, and thus the door opened, in the event of an impact. It is an object of the present invention to provide an improved vehicle door latching arrangement. The present invention is based on the provision of an arrangement whereby an external handle of a vehicle door is connected to a latch thereof by a cable that has a certain amount of "slack" in its length. Since the cable is not taut, it does not extend in the most direct path, for example in a straight line, between the handle and latch mechanisms. In accordance with one aspect of the present invention, there is provided an arrangement in which an external handle of a door of a vehicle is connected to a latch of the door for releasing the latch from a keeper thereby to allow the door to open, the handle and the latch being separated by a direct distance d. wherein a cable is connected at one of its ends to the handle and at its other end to the latch to effect said releasing, wherein the cable follows a path of length D that is curved and extends between the handle and the latch, and wherein the ratio D/d > 1.1. By a "direct" distance is meant the shortest distance avoiding any intervening component, usually along a straight line, between the two relevant locations. A path is understood to be "curved" when, at least over part of its length and usually along the whole of its length, the path is other than a straight line. A curved path may be of regular or irregular shape, and may form a loop, so as to cross back on itself. The curved path may lie on. inside, outside or cross over an imaginary semi-circle extending between the relevant two locations. The ratio D/d is preferably > 1.3. and may be > 1.5. For example, if the curved path follows a semicircle, then D/d = 1.57. The cable may be a co-axial cable, and is preferably a Bowden cable, wherein an inner wire thereof is fixed at respective ends to an operating mechanism of the handle and of the latch, and an outer, protective sheath thereof is fixed at each of its ends to the door of the vehicle. It will be appreciated that with the slack provided by the cable in the arrangement of the present invention, the vehicle may sustain an impact that will deflect the cable to an extent that is insufficient for the cable to be made taut enough so as to operate the latch and thus to cause the door to become open. Embodiments of vehicle latching arrangements, each in accordance with the present invention, will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a schematic side view of an arrangement: Figure 2 shows one embodiment of curved path of the cable of the arrangement; and Figure 3 shows a further embodiment of a curved path of the cable. Referring to Figure 1. a handle mechanism 2 is secured to the outside of a vehicle door 4, and a latch mechanism 6 is secured to the inside of the door 4. An external handle 8 of the mechanism 2 is arranged in operation to rotate an elongate spindle 10 about its longitudinal axis. A Bowden cable 12 comprises an outer sheath 14 that is fixed by flanges 16 and 18 at respective ends thereof to the door 4 adjacent the handle mechanism 2 and latch mechanism 6 respectively. The cable 12 also has an inner wire 20 that is slidable within the sheath 14. The wire 20 projects from the cable 12 beyond the flange 16 and is secured by means of a clamp 22 to an end of the spindle 10 of the handle mechanism 2. At its other end. the wire 20 projects beyond the flange 18 and is secured to a release lever 24 that is connected at the latch mechanism 6 to a latch 26 of the door 4. Operation of the handle 8 on the outside of the door 4 rotates the spindle 10 and the clamp 22 attached thereto, which pulls the wire 20 of the cable 12 through the sheath 14 in the direction from the flange 18 towards the flange 16. The movement of the door handle 8 is thus transferred to the release lever 24 which moves to withdraw the latch 26 from a keeper 28 mounted on a door post 30 of the frame of the vehicle, thereby to allow the door 4 to be opened. As can be seen from Figure 1. the path followed by the cable 12. and in particular by its inner wire 20 from the point A at which it is attached to the handle mechanism 2 to the point B at which it is attached to the latch mechanism 6. is curved and deviates from the direct, straight line, path between the points A and B. In the event of an impact on the vehicle in the region of the door 4 and or door post 30, it can be seen that the points A and B can be moved apart, for example by buckling of the door 4. an appreciable distance before the cable 12 becomes taut and causes the latch 26 to be released and the door 4 to become open. It will be appreciated that this would not be the case were the cable 12 to extend directly in a straight line from the handle mechanism 2 to the latch mechanism 6, whereby the points A and B would be joined in a straight line by the cable 12. Referring to Figure 2. points Al and Bl of this embodiment correspond, respectively, to the points A and B associated with the handle mechanism 2 and latch mechanism 6 of Figure 1. A wire 40, for example an inner wire of a Bowden cable, is shown extending between the points Al and Bl over a curved path that is substantially bell-shaped and has two substantially-linear portions. The path of the wire 40 is appreciably longer than the (imaginary) straight line path 42 between the points Al and Bl. Alternatively, the inner wire of the co-axial cable may follow a different path, forming part of a circle shown in broken outline 44 that extends through the points Al and Bl . Referring to Figure 3. an inner wire 50 of a co-axial cable extends between points A2 and B2. corresponding to the points A and B associated with the handle and latch mechanisms 2 and 6 respectively of Figure 1. The wire 50 extends between the points A2 and B2 in a path that is curved to form a loop, the total length of the path followed by the wire 50 being appreciably greater than the direct, linear (imaginary) path 52 between the points A2 and B2. It will be appreciated that the cable of the arrangement of the invention may lie along a differently-shaped curved path between the handle and latch of the arrangement whilst maintaining the relationship D/d > 1.1 , as set out above.

Claims: Claims 1. An arrangement in which an external handle of a door of a vehicle is connected to a latch of the door for releasing the latch from a keeper thereby to allow the door to open, the handle and the latch being separated by a direct distance d. wherein a cable is connected at one of its ends to the handle and at its other end to the latch to effect said releasing, wherein the cable follows a path of length D that is curved and extends between the handle and the latch, and wherein the ratio D/d > 1.1. 2. An arrangement according to claim 1. wherein the cable is a co-axial cable, wherein an inner wire thereof is fixed at respective ends to an operating mechanism of the handle and of the latch, and wherein an outer sheath thereof is fixed to the door of the vehicle. 3. An arrangement according to claim 2, wherein the inner wire of the cable is arranged to slide longitudinally within the outer sheath of the cable, the cable preferably being a Bowden cable. 4. An arrangement according to any one of the preceding claims, wherein substantially the whole of the length of the cable path is curved. 5. An arrangement according to any one of the preceding claims, wherein D/d > 1.3. 6. An arrangement as claimed in any one of the preceding claims, wherein D/d > 1.5. 7. A vehicle door latch releasing arrangement substantially as hereinbefore described with reference to the accompanying drawings.

Inventors: BLAND TIMOTHY, FISHER SYDNEY EDWARD, SPURR NIGEL VICTOR, BLAND, TIMOTHY, FISHER, SYDNEY, EDWARD, SPURR, NIGEL, VICTOR
Applicants: BLAND TIMOTHY, FISHER SYDNEY EDWARD, MERITOR LIGHT VEHICLE SYS LTD, SPURR NIGEL VICTOR, BLAND, TIMOTHY, FISHER, SYDNEY, EDWARD, MERITOR LIGHT VEHICLE SYSTEMS (UK) LIMITED, SPURR, NIGEL, VICTOR
Application year: 2000
Main classification: E05B65
IPC codes: E05B53, E05B65