FR3112730A1 - Optical box for a motor vehicle headlamp comprising at least one fixing lug allowing rupture kinematics according to two distinct constraints - Google Patents

Abstract

The invention relates to an optical housing for a motor vehicle headlamp comprising at least one fixing lug allowing a breaking kinematics according to two distinct constraints The optical housing (2) comprises at least one fixing lug (4) intended to allow the securing of the optical box (2) to a body of a motor vehicle. The fixing lug (4) extends between a proximal part (8) integral with the optical box (2) and a distal part (14) comprising a cap abutment (18). The invention is remarkable in that the proximal part (8) of the fixing lug (4) is held to the optical box (2) by means of at least one buttress (10) comprising a notch (12), and the distal part (14) of the fixing lug (4) comprises at least one opening (20) running along the periphery of the cowl abutment (18). (Figure 2)

Description

Optical box for a motor vehicle headlamp comprising at least one fixing lug allowing rupture kinematics according to two distinct constraints

The present invention relates to the technical field of lighting and signaling for motor vehicles. More particularly, the present invention relates to an optical housing for a motor vehicle headlight.

Motor vehicles are equipped with headlamps to warn road users of the position and intentions of the motor vehicle. A projector consists of an optical box comprising an opening closed by a transparent wall called glass. The headlamp protects a set of light sources coupled to optical devices of the lens and/or reflector type from the external environment, so as to allow the projection of one or more light beams in accordance with the regulations in force.

The optical housing of the headlamp comprises several fixing lugs on its surface, intended to allow the headlamp to be held by screwing into a dedicated housing in the bodywork of a motor vehicle.

Safety standards require partial separation of the headlamp from the motor vehicle, in the event of a frontal impact with a pedestrian, in order to allow movement of the bonnet to cushion the impact of the impact. In the event of a more serious frontal impact, for example during a collision against street furniture, it is recommended that the headlight be separated more clearly from the motor vehicle in order to prevent the transmission of the shock to adjacent parts of the headlight. The document FR2897804 B1 thus proposes a device for guiding the movement and retaining of an optical unit on the structure of a motor vehicle in the event of an impact, in order to protect the bodywork from irreversible deformation by reducing the transmission of the impact to adjacent parts of the projector.

The aim of the invention is to propose a solution allowing a fixing lug of an optical box for a motor vehicle headlamp to satisfy a breaking kinematics according to two distinct stresses, a partial break during a moderate impact and a break global during a shock of greater intensity.

For this, the invention proposes an optical housing for a motor vehicle headlamp, comprising at least one fixing lug intended to allow the fastening of the optical housing to a bodywork of a motor vehicle, the fixing lug extending between a part proximal integral with the optical housing and a distal portion comprising a cap abutment.

The invention is characterized in that the proximal part of the fixing lug is held to the optical housing by means of at least one buttress comprising a notch, and in that the distal part of the fixing lug comprises at least an opening along the periphery of the bonnet abutment.

Advantageously, the presence of an opening at the level of the distal part of the fixing lug makes it possible to achieve a shrinkage of material near the cover abutment, so as to be able to precisely control the breaking force necessary to be applied to the bonnet stopper to allow it to be detached from the mounting bracket.

According to another advantage, the presence of a notch at the level of a buttress connecting the proximal part of the fixing lug to the optical housing, also makes it possible to carry out a removal of material at the level of the buttress, so as to be able to precisely control the breaking force required to be applied to the mounting bracket to detach it from the optical housing.

In other words, the invention proposes an optical headlamp comprising at least one fixing lug characterized by a first fuse between a cover stop and a fixing lug, and a second fusibility between the fixing lug and the optical housing . According to the invention, the term "fusibility" refers to the term of the control or rupture of an object. The invention thus makes it possible to satisfy the kinematics of ruptures of a fixing lug provided with a bonnet stopper, according to two very distinct constraints: rupture of the bonnet stop present on the leg to accompany movement of the bonnet during a pedestrian impact on the head, for example, and overall breakage of the fixing lug during a larger impact which requires supporting a greater effort during a small impact against a wall, for example.

The invention also relates to the following embodiments, possibly combined together:

- At least one opening is located vis-à-vis the cover stop;

- the smallest distance between an opening and the base of the bonnet stop is equal to or less than 5 mm, preferably between 0 mm and 3 mm;

- at least one opening extends over at least 50% of the length of the periphery of the bonnet stopper, preferably over at least 70% of the length of the periphery of the bonnet stopper;

- at least one opening in the form of a slot whose width is between 1 mm and 5 mm, preferably between 1 mm and 2 mm;

- the distal part of the fixing lug has at least one opening, so as to allow the detachment of the bonnet abutment from the fixing lug, when a mechanical pressure greater than or equal to 30 DAN is applied to the bonnet abutment . ;

- the proximal part of the fixing lug is held to the optical housing by means of at least one buttress comprising a notch extending over at least 50% of the height of the buttress, so as to allow detachment of the part proximal to the optical housing mounting bracket, when a mechanical pressure greater than or equal to 60 DAN is applied to the mounting bracket;

- a notch of at least one buttress extends parallel or substantially parallel to the proximal part of the fixing lug;

- the fixing lug is held to an outer face of the optical housing, and the proximal part of the fixing lug extends perpendicular or substantially perpendicular to said face;

- the distal part of the fixing tab fe extends perpendicularly or substantially perpendicular to the proximal part of the fixing tab.

Other advantages and characteristics may emerge more clearly from the description that follows.

The invention will be better understood on reading the following description, given solely by way of non-limiting example and made with reference to the drawings in which:

shows a schematic view of an optical box comprising a fixing lug according to the invention;

represents a partial schematic view of the optical box illustrated in FIG. 1;

shows another partial schematic view of the optical box shown in Figure 1.

In these figures, the same references are used to designate the same elements.

As a reminder, the invention proposes an optical box for a motor vehicle headlamp, satisfying a kinematics of rupture according to two distinct constraints, a partial rupture during a moderate impact and an overall rupture during an impact of greater intensity.

Figures 1 to 3 show a non-limiting embodiment of an optical box 2 for a motor vehicle headlight, comprising a fixing lug 4 according to the invention.

The fixing lug 4 is linked to an outer face 6 of the optical box 2. According to the present example, the fixing lug is located in the upper part of the optical box, in order to subsequently allow the optical box to be held against a bodywork wing d a motor vehicle.

The fixing lug 4 comprises a proximal part 8 linked to the external face 6 of the optical box. The proximal part 8 is held perpendicular or substantially perpendicular to said face, by means of several buttresses 10 visible in FIGS. 1 and 2. At least four buttresses comprise a notch 12 extending parallel or substantially parallel to the proximal part 8 of the mounting bracket. Each notch 12 extends over at least 50% of the height of the buttress, preferably over at least 80% of the height of the buttress. The width of each notch 12 is between 1 mm and 5 mm, preferably between 1 mm and 3 mm.

By the terms “height” and “width” is meant respectively a direction normal to the outer face 6 of the optical housing and a direction normal to the proximal part 8 of the fixing lug.

Advantageously, the indentations 12 allow material to be removed at the level of each buttress 10, so as to be able to precisely control the breaking force necessary to be applied to the fixing lug 4 to detach the proximal part 8 from the optical housing 2 .

According to the present example, the number of stiffeners 10 comprising a notch 12, as well as the dimensions of each notch 12 are adapted so that the proximal part 8 of the fixing lug detaches from the optical housing 2, when a mechanical pressure equal or greater than 60 DAN is applied to the fixing lug 4. The term “DAN” refers to the term decanewton.

The fixing lug 4 comprises a distal part 14 extending perpendicular or substantially perpendicular to the proximal part 8. The distal part 14 comprises a passage 16 intended to allow the insertion of a screw or a nut in order to maintain the mounting lug 4 against a body wing of a motor vehicle.

The proximal part 8 of the fixing lug supports a cover abutment 18 extending perpendicularly or substantially perpendicular to the proximal part 8 as well as the external face 6 of the optical box 2.

Advantageously, the distal part 14 of the fixing lug comprises an opening 20 located opposite the cover abutment 18 visible in FIGS. 2 and 3. The opening 20 has the shape of a slot whose the width is between 1 mm and 5 mm. This embodiment advantageously allows the evacuation of a water residue on the distal part 14 of the fixing lug 4.

The smallest distance between the opening 20 and the base of the cowl stop 18 is equal to or less than 5 mm, preferably equal to or less than 2 mm.

The aperture 20 extends along the periphery of the base of the hood abutment 18. According to the present example, the aperture extends over at least 50% of the length of the periphery of the hood abutment, preferably over at least 80% of the length of the perimeter of the bonnet stopper.

Advantageously, the opening 20 makes it possible to remove material close to the cowl abutment 18, so as to be able to precisely control the breaking force necessary to be applied to the cowl abutment to allow its detachment from the tab of the fixation. The opening 20 is sized so that the cowl stop 18 detaches from the mounting lug when a mechanical pressure equal to or greater than 30 DAN, preferably between 30 DAN and 40 DAN, is applied to the mounting lug 4.

In other words, the optical housing 2 illustrated in Figures YY to YY thus comprises a stepped mounting lug 4, comprising a first stage delimited by the proximal part 8 of the mounting lug, able to give way when the optical housing undergoes a mechanical shock of medium intensity, and a second stage comprising the cowl abutment 18, able to yield when the mechanical cowl undergoes a mechanical shock of lower intensity.

The fixing lug 4 according to the invention comprises detachment means capable of responding to two distinct collision situations. As a result, the mounting bracket allows the production of a more compact optical box while respecting the safety standards in force.

Claims (10)

Optical box (2) for a motor vehicle headlamp, comprising at least one fixing lug (4) intended to allow the fixing of the optical box (2) to a bodywork of a motor vehicle, the fixing lug (4) extending between a proximal part (8) secured to the optical housing (2) and a distal part (14) comprising a cap abutment (18), characterized in that the proximal part (8) of the fixing lug (4) is held to the optical unit (2) by means of at least one buttress (10) comprising a notch (12), and in that the distal part (14) of the fixing lug (4) comprises at least one opening (20) along the periphery of the hood abutment (18). Optical unit (2) for a motor vehicle headlight according to claim 1, characterized in that at least one opening (20) is located opposite the bonnet stop (18). Optical box (2) for motor vehicle headlamp according to Claim 1 or 2, characterized in that the smallest distance between an opening (20) and the base of the bonnet stop (18) is equal to or less than 5 mm. Optical unit (2) for motor vehicle headlamp according to Claim 3, characterized in that at least one opening (20) extends over at least 50% of the length of the periphery of the bonnet stop (18). Optical box (2) for motor vehicle headlamp according to one of Claims 1 to 4, characterized in that at least one opening (20) in the form of a slot, the width of which is between 1 mm and 5 mm . Optical box (2) for motor vehicle headlamp according to one of Claims 1 to 5, characterized in that the distal part (14) of the fixing lug (4) comprises at least one opening (20), so as to allow the detachment of the bonnet stopper (18) from the fixing lug (4), when a mechanical pressure equal to or greater than 30 DAN is applied to the bonnet stopper (18). Optical box (2) for motor vehicle headlamp according to one of Claims 1 to 6, characterized in that the proximal part (8) of the fixing lug (4) is held to the optical box (2) via at least one buttress (10) comprising a notch (12) extending over at least 50% of the height of the buttress (10), so as to allow the detachment of the proximal part (8) of the fixing bracket (4) of the optical unit (2), when a mechanical pressure equal to or greater than 60 DAN is applied to the fixing lug (4). Optical box (2) for a motor vehicle headlamp according to claim 7, characterized in that an indentation of at least one buttress (10) extends parallel or substantially parallel to the proximal part (8) of the fixing lug (4). Optical box (2) for motor vehicle headlamp according to one of Claims 1 to 8, characterized in that the fixing lug (4) is held on an external face of the optical box (2), and in that the part proximal (8) of the fixing lug (4) extends perpendicularly or substantially perpendicularly to said face. Optical box (2) for motor vehicle headlamp according to one of Claims 1 to 9, characterized in that the distal part (14) of the fixing lug extends perpendicularly or substantially perpendicularly to the proximal part (8) of the fixing lug (4).