Vehicle lamp assembly

Abstract

 The present invention provides a housing for a lamp assembly (10) comprising two housing parts (12,90) and sealing means between the housing parts; the sealing means comprises an edge channel means (30) on one of the housing parts (12), a sealing strip (50) in the edge channel means (30) and an abutment means (96) on the other housing part (90) for compressing the sealing strip (50) in the edge channel means (30) to form a liquid-tight seal between the housing parts. A plurality of spaced drainage means (100) are provided in the edge channel means, the drainage means being located so that irrespective of the orientation of the housing, when considered in the mounted position, at least one of the drainage means is disposed at the bottom of the housing; the sealing strip (50) can be positioned to by-pass the edge channel means at the drainage means to provide a drain for liquid accummulated in the housing to drain therefrom.

Description

[0001] The present invention relates to a vehicle lamp assembly.

[0002] A vehicle which is used on a public highway is typically provided with various lights and illuminated indicators such, for example, as head-lamps, tail-lamps, side-markers and direction indicators. In many vehicles, particularly commercial vehicles and trailers therefor, the lights at each of the front and rear ends of the vehicle are provided in two unitary lamp assemblies which are spaced one from the other across the front-rear direction of the vehicle, one towards each side thereof.

[0003] A typical vehicle lamp assembly includes a housing which can be fastened to the vehicle, the housing comprising a receptacle, reflector tray received in the receptacle and a transparent lens closure. The receptacle comprises a generally rectangular back wall which carries means for securing the housing to the vehicle and four side walls, each side wall terminating away from the back wall in a front edge. The reflector tray is shaped to define one or more reflectors which are arranged along a line parallel to the long sides of the receptacle, and comprises bulb-holding means juxtaposed each reflector. The lens closure comprises one or more coloured diffuser lens portions and is fastened to the receptacle such that the periphery of the lens closure is seated on the said front edges of the side walls, and each diffuser lens portion is disposed juxtaposed one of the said reflectors thereby to provide a required light or indicator function. The back wall of the receptacle has one or more apertures formed therethrough for cable access, thereby to allow the bulbs carried in the reflector tray to be connected to a remote power supply. The housing is typically mounted on a vehicle with the long sides disposed horizontally such that the lights and indicators are arranged on a horizontal line across the front-rear direction of the vehicle.

[0004] In order to allow operation under substantially all weather conditions, it is generally desirable that the lamp assembly is water-resistant. In vehicles for use in off-road applications, the lamp assembly may be subjected to continual splashing and, occasionally, total immersion. The housing, therefore, comprises a sealing gasket interposed between the receptacle and the lens closure. The receptacle is provided with a gasket-receiving channel which is formed in the front edge of each of the side walls, and the lens closure has a peripheral rib which is received in the channel; the gasket being received in the channel between the side walls and the rib, such that when the lens closure is fastened to the receptacle, the gasket is compressed to form a seal therebetween.

[0005] Inevitably, however, under severe wet conditions, some water enters into the housing through e.g. the cable access aperture and/or small gaps between the lens closure and the receptacle. Moreover, in a vehicle which is parked out-of-doors in an unheated environment, condensation generally collects inside the housing as a result of the daily fluctuations in atmospheric temperature.

[0006] There is, therefore, a requirement for a vehicle lamp assembly which is provided with drainage means to allow liquid accumulated in the housing to drain therefrom.

[0007] Furthermore, in a vehicle which is used with a close-coupled trailer, it is generally unsatisfactory to mount the lamp assemblies on the rear end of the vehicle, between the rear end and the trailer, with their long sides oriented horizontally, because the trailer can foul the lamp assembly at or towards the extremity of its permitted yaw about its coupling to the vehicle. It is, therefore, desirable to mount the rear lamp assemblies with the long sides oriented vertically thereby to allow the trailer to move in a wider arc of yaw.

[0008] It will be appreciated, therefore, that the drainage means is required to provide adequate drainage for the lamp assembly when the latter is oriented alternatively vertically or horizontally.

[0009] There is, therefore, a general requirement for a lamp assembly which is provided with drainage means, and which latter permits liquid accumulated in the housing to drain therefrom irrespective of the mounted orientation of the lamp assembly on the vehicle.

[0010] According to one aspect of the present invention, therefore, there is provided a housing for a lamp assembly comprising two housing parts which can be assembled to define a lamp cavity, wherein sealing means is provided between the housing parts; the sealing means comprising an edge channel means in one of the housing parts, a sealing strip disposed in the edge channel means and an abutment means on the other housing part for engaging the sealing strip in the channel means to form a liquid-tight seal between the housing parts; characterised in that the edge channel means includes a plurality of spaced drainage means; the drainage means being positioned such that irrespective of orientation of the housing, when considered in the mounted position, at least one of the drainage means is disposed at the bottom of the housing; and the sealing strip can be positioned to by-pass the edge channel means at the one drainage means to provide a drain for liquid accummulated in the housing to drain therefrom.

[0011] The present invention also includes a vehicle lamp assembly comprising a housing in accordance with the invention.

[0012] Typically, one housing part may be a receptacle, and the other housing part may be a lens closure for the receptacle. In some embodiments, the receptacle may accommodate a reflector tray.

[0013] In one aspect of the invention, the edge channel means may be formed in the receptacle; the abutment means may be a rib formed on the lens closure. Typically the sealing strip is a sealing gasket.

[0014] The receptacle may have one or more side walls; the edge channel means may be formed in or carried by the side wall(s).

[0015] In a particular aspect of the invention, each drainage means may be constituted by a "chicane drainage means".

[0016] By the term "chicane drainage means" as used herein is meant means formed in the said edge channel means to allow the said sealing gasket to be removed from the edge channel means over a minor part of its length, thereby to provide a small aperture between the receptacle and the said lens closure.

[0017] Typically, the edge channel means may comprise two spaced channel walls carried on the one or more side walls; each channel wall may be formed as a substantially continuous loop on the side walls. The chicane drainage means may comprise two cut-outs formed in one of the channel walls to allow the gasket to be removed from the edge channel means at one of the cut-outs and to be returned to the edge channel means via the other cut-out.

[0018] The housing may be of any shape; the one or more side walls may carry spaced chicane drainage means so that, irrespective of the orientation of the housing in its fastened position in a vehicle, at least one of the chicane drainage means is disposed at the bottom of the housing; the sealing gasket may be removed from the edge channel means at the one chicane drainage means to allow liquid accumulated in the housing to drain therefrom. It will be appreciated that the present invention comprehends embodiments in which more than one chicane drainage means can be selected to provide more than one drainage point.

[0019] In a particular aspect, the receptacle may comprise a generally rectangular back wall which carries four side walls. Each side wall may be connected at each end to one of the other side walls to define a corner therebetween and may terminate remote from the back wall in a front edge. The receptacle may be moulded as a unitary construction from a structural plastics material such as polypropylene.

[0020] In some embodiments, a chicane drainage means may be formed at each corner of the housing. One cut-out may be formed in the one channel wall on one of the side walls defining the corner; the other cut-out may be formed in the one channel wall on the other of the side walls defining the corner. Thus, where drainage is required at the corner, the sealing gasket may be removed from the edge channel means around the corner to follow a generally sinuous path inside the housing between the two cut-outs. A corner chicane drainage means may provide drainage for the housing in any orientation between a first position in which the one side wall is disposed lowermost and a second position in which the other side wall is disposed lowermost; irrespective of the orientation of the housing, the corner and the corner chicane drainage means at the one corner are disposed at the bottom of the housing to permit drainage of water accumulated in the housing therefrom.

[0021] The lamp assembly may be provided with chicane drainage means at each of the four corners of the housing. In this embodiment, the lamp assembly may be oriented in any position with any of the side walls disposed lowermost and, irrespective of the orientation, at least one of the said corner chicane drainage means may be used to provide drainage for the housing.

[0022] In a different embodiment of the invention, the receptacle may be provided additionally with one or more spaced side-wall chicane drainage means formed in the edge channel means on one or more of the side walls remote from the corners. According to this different embodiment, therefore, in any orientation of the housing, at least one corner chicane drainage means may be selected with the additional possibility of utilising one or more side-wall chicane drainage means.

[0023] The sealing gasket may be formed of any flexible water-resistant material. In one embodiment of the invention, the sealing gasket may be formed from a foamed neoprene material having blind pores. Typically, the sealing gasket may have a generally circular cross-section.

[0024] At a corner chicane drainage means, the sealing gasket may be disposed between the reflector tray and the side walls defining the corner. Under the influence of gravity and/or as a result of vibration of the vehicle the reflector tray may tend to urge the sealing gasket against the side walls. Owing to the respective shapes of the sealing gasket and the corner, however, the sealing gasket may follow a path which is not wholly contiguous the side walls juxtaposed the corner and, irrespective of the pressure applied by the reflector tray, may leave at least a small aperture between the gasket and the side walls to provide drainage for the housing.

[0025] The man skilled in the art will appreciate that the housing in accordance with the present invention may be provided with a plurality of chicane drainage means which may optionally be used as drains for the assembly. Where more than one such chicane drainage means is provided, the sealing gasket may be "looped out" of the edge channel only in the lowermost means provided on the assembly when considered in the position as mounted. In this way, the remaining drainage means remain sealed with the gasket means disposed in the edge channel thus restricting ingress of moisture at these locations.

[0026] The receptacle may be provided with one or more apertures to allow cable access. In some embodiments of the invention, the apertures may carry water-proof grommets to provide a seal between the housing and the cables extending through the receptacle.

[0027] Following is a description by way of example only and with reference to the accompanying informal drawings of methods of carrying the present invention into effect.

[0028] In the drawings:-

[0029] Figure 1 is a sectional view through a lamp assembly in accordance with the present invention.

[0030] Figure 2 is a part cut-away plan view of the lamp assembly of Figure 1.

[0031] Figure 3 is a different sectional through the lamp assembly of Figure 1.

[0032] Figure 4 is a detail of the cut-away part of Figure 2.

[0033] In Figures 1 and 2, a lamp assembly (10) comprises a box-shaped receptacle (12) of rectangular cross-section which is moulded as a single piece from a polypropylene plastics material. Said receptacle (12) comprises a rectangular back wall (14) and four side walls - two long side walls (17, 19) and two short side walls (16, 18); which side walls (16-19) define four corners (20, 21, 22 and 23) therebetween and terminate remote from back wall (14) in a peripheral front edge (24). Said front edge (24) is shaped to define a channel (30) of U-shaped cross-section and comprises parallel spaced-apart inner and outer channel walls (32) and (34) respectively (see Figure 4). Juxtaposed each corner (20-23), inner channel wall (32) comprises two cut-outs (40-41), which define a chicane drainage means. The cut-outs (40, 41) are disposed on opposed sides of the corner, and each extends from the front of the inner channel wall (32) almost to the front surface (35) at the back of the channel (30).

[0034] Channel (30) accommodates a sealing gasket (50) which is formed as a continuous loop from a water-resistant neoprene material.

[0035] Back wall (14) carries four posts (not shown) each of which extends forwardly from the back wall to terminate just forward of front edge (24) in a circular front surface. Each post is provided with a threaded bore which extends from said front surface towards back wall (14).

[0036] The back wall (14) of receptacle (12) also carries two spaced bolts (102) which can be used to fasten the lamp assembly (10) to a vehicle.

[0037] Receptacle (12) accommodates a reflector tray (70) which is generally rectangular in plan view having four right-angle corners disposed juxtaposed the corners (20-23) of receptacle (12) and is moulded from a thermosetting plastics material. Reflector tray (70) is shaped to define a plurality of spaced reflectors (72) which are arranged on a line parallel to the long sides of housing (12); each reflector (72) has a circular aperture (74) formed therein which extends through the reflector tray (70) from a front surface (77) to a back surface (79) thereof. The back surface (79) of reflector tray (70) carries a conducting metal strip (80) which is shaped to provide a bulb-holder (76) juxtaposed each aperture (74). Said bulb-holder comprises a pair of slots (not shown) formed in the strip (80) which slots are shaped to receive radially extending spigots on a bulb (78) to hold the bulb (78) such that its filament is disposed at the focal point of reflector (72). The bulb holder (78) also forms a first electrical terminal arranged to contact the side terminal of the bulb (78). Juxtaposed each aperture (74), the back surface (79) of the reflector tray (70) also carries a conducting plate (82) which includes a leaf-spring (84) arranged to form a second electrical terminal to contact the bottom terminal of the bulb (78).

[0038] The back wall (14) of receptacle (12) is provided with one or more apertures to allow cable access to the said conducting strip (80) and conducting plates (82) thereby to permit the same to be connected to a remote power supply such, for example, as a 12V lead-acid battery.

[0039] Reflector tray (70) also has four generally cylindrical conduits (not shown) formed therein, each of which extends from said front surface (77) to said back surface (79) and accommodates one of the said four posts carried by the back wall (14), thereby to locate the tray (70) in the receptacle (12).

[0040] Lamp assembly (10) further comprises a generally rectangular lens closure (90) which is formed from a transparent plastics material and is fastened to receptacle (12) by four screws (92) which extend through apertures formed in the lens closure (90) into the threaded bores in the said posts which protrude from said cylindrical conduits towards their front ends. The peripheral edge of the lens closure (90) is coterminus with the front edge (24) of side walls (16, 19), and the back surface of the lens closure (90) is provided with a peripheral rib (96) which is received in said channel (30). Rib (96) has a depth such that it squashes the sealing gasket (50) accommodated within the channel (30) against the front surface (35) of the channel (30) to form a water-resistant seal between lens closure (90) and receptacle (12).

[0041] Juxtaposed each corner (20-23) of the receptacle (12), the sealing gasket (50) may be removed from the channel (30) over a minor portion of its length at the said chicane drainage means, such that the gasket (50) is removed from the channel (30) via one of the cut-outs (40, 41) and re-enters the channel (30) on the opposed side of the corner via the other of the said cut-outs (41, 40). The rib (96) terminates short of the front surface (35) of channel (30) to provide a drainage aperture (100) between the rib (96) and the said front edge (24). Between said cut-outs (40, 41) the sealing gasket (50) follows a generally sinuous path (60) under one of said corners of reflector tray (70).

[0042] Lens closure (90) is divided into a plurality of diffuser lens portions (94), each of which is disposed juxtaposed one of the said reflectors (72). Each diffuser lens portion (94) is formed from a plastics material having a particular colour to provide a special lamp-function in conjunction with one of the said reflectors (72) and its associated bulb (78). Each diffuser lens portion (94) comprises a plurality of "pillow-case" lenses (98) which are disposed contiguously on the lens portion (94).

[0043] In use, light from the filament of bulb (78) is shaped by reflector (72) to form a substantially parallel beam of light which impinges on the diffuser lens portion (94). The "pillow-case" lenses (98) serve to disperse the light transmitted by the lens closure (90) over a predetermined angle so that the light from the lamp assembly is visible over a required solid angle.

[0044] In accordance with the present invention, therefore, a lamp assembly as hereinbefore described can be fastened to a vehicle with any of the said side walls (16-19) disposed lowermost, and, in any fastened position, at least one of the corners (20-23) is disposed at the bottom of the receptacle (12), and the sealing gasket (50) may be removed from the channel (30) via the cut-outs (40, 41) juxtaposed said one corner to provide a drainage aperture between the lens closure (90) and the receptacle (12).

Claims

1. A housing for a lamp assembly comprising two housing parts which can be assembled to define a lamp cavity, wherein a sealing means is provided between the housing parts; the sealing means comprising:
   an edge channel means (30) on one of the housing parts,
   a sealing strip (50) disposed in the edge channel means, and
   an abutment means (96) on the other housing part for engaging the sealing strip in the edge channel means to form a liquid-tight seal between the housing parts;
characterised in that the edge channel means includes a plurality of spaced drainage means, the drainage means being positioned such that irrespective of the orientation of the housing, when considered in the mounted, position at least one of the drainage means is disposed at the bottom of the housing; the sealing strip can be positioned to by-pass the edge channel means at the one drainage means to provide a drain for liquid accummulated in the housing to drain therefrom.

2. A housing as claimed in claim 1 wherein the one housing part is a receptacle (12) and the other housing part is a lens closure (90) for the receptacle.

3. A housing as claimed in claim 2 wherein the receptacle has one or more side walls, the edge channel means being formed in or carried by the side wall(s).

4. A housing as claimed in claim 1, claim 2 or claim 3 wherein the edge channel means comprises two spaced channel walls (32,34).

5. A housing as claimed in claim 4 wherein each drainage means is constituted by a chicane drainage means.

6. A housing as claimed in claim 5 wherein the chicane drainage means comprises two spaced cut-outs (40, 41) in one of the channel walls arranged such that the sealing strip can be removed from the edge channel means at one of the cut-outs and returned to the edge channel means at the other cut-out.

7. A housing as claimed in any of claims 2 to 6 wherein the receptacle comprises a generally rectangular back wall (14) and four side walls (16,17,18,19).

8. A housing as claimed in claim 7 wherein a chicane drainage means is formed at each corner (20,21,22,23) of the housing.

9. A housing as claimed in claim 8 wherein a cut-out is formed in a channel wall on one of the side walls defining the corner, and another cut-out is formed in the channel wall on the other of the side walls defining the corner.

10. A housing as claimed in any of claims 7 to 9 wherein one or more side wall chicane drainage means are formed in the edge channel means on one or more of the side walls remote from the corners.

11. A lamp assembly (10) comprising a housing as claimed in any of claims 1 to 10.

Drawing