HINGE MECHANISM

Abstract

A hinge mechanism 10 to lift the rear edge of a bonnet 11 of a motor vehicle comprises an upper leaf 13 connected to the bonnet 11, a lower leaf 12 connected to the body structure of the vehicle and a middle leaf 14 connected to the upper leaf 13 and the lower leaf 12. The middle leaf 14 is connected to the upper leaf 13 by means of a stud 16 and a slot 17 connection so as to limit movement of the bonnet from a normal position to a deployed position under an upward force exerted by a lift actuator. The stud 16 and slot 17 connection is provided with a resiliently deformable element 30 arranged at the end of the slot for dissipating impact energy of the stud 16 against the slot 17 during the upward force.

Description

The invention will now be described by way of example with reference to the accompanying drawings of which:

FIG. 1 is a schematic of a hinge mechanism connected to the rear edge of a bonnet in its normal position,

FIG. 2 is a view similar to FIG. 1 but showing the hinge mechanism in its open position, i.e. when the bonnet is opened in the normal way,

FIG. 3 is a view similar to FIG. 1 but showing the hinge mechanism in an extended position in the event of a detected collision with a pedestrian,

FIG. 4 is a scrap view in to the direction of arrow B in FIG. 1 to a larger scale, and

FIGS. 5 and 6 are views similar to FIG. 4 but showing two alternatives respectively.

Claims

1. A hinge mechanism for providing a hinged connection between a bonnet and a body structure of a motor vehicle, the hinge mechanism allowing the rear edge of the bonnet to be lifted from a normal position to a deployed position under an upward force, the hinge mechanism including first and second hinge members which in normal position are fast with each other but which move relative to each other when the bonnet is moved from the normal position to the deployed position, the first hinge member having a slot and the second hinge member having a stud which is slidable in the slot during movement of the bonnet from the normal position into the deployed position and wherein energy dissipating means is provided to dissipate impact energy of the stud against the end of the slot as the bonnet approaches the deployed position.

2. A hinge as claimed in claim 1 in which the energy dissipating means is a resiliently deformable element connected to the first hinge member at one end of the slot.

3. A hinge as claimed in claim 2 in which the deformable element has at least one cavity.

4. A hinge as claimed in claim 3 in which the or each cavity is elongate and has a longitudinal axis which is substantially perpendicular to the travel direction of the stud.

5. A hinge as claimed in claim 4 in which each cavity is bone shaped.

6. A hinge as claimed in any one of claim 2 to 5 in which the element has a buffer wall arranged to abut the stud.

7. A hinge as claimed in claim 6 in which the buffer wall has a surface that curves outward.

8. A hinge as claimed in any one of claim 2 to 7 in which the element is made of elastomeric material.

9. A hinge as claimed in claim 1 in which the energy dissipating means includes at least one bridge piece formed between an aperture and one end of the slot such that the or each bridge piece can deform under impact energy of the stud against the end of the slot as the bonnet approaches the deployed position.

10. A motor vehicle having at least one hinge mechanism according to any preceding claim.

11. A hinge mechanism arranged substantially as described herein with reference to FIGS. 1 to 4, or FIG. 5 or FIG. 6 of the accompanying drawings.