Vehicle undershielding arrangements

Abstract: An undershield for protecting and shielding the underside of a motor vehicle engine from debris in the road. The undershield is provided with a vent (4), which is protected by a deflector (6) on the underside of the undershield and a protective element (5) on the topside of the undershield. The deflector (6) deflects the air flow under the vehicle which causes a reduction in pressure in the region of the vent (4). This causes the warm air in the engine compartment (2) to be drawn out, thus cooling the engine.

Description: The invention relates to an undershield for a motor vehicle engine compartment, comprising a panel for attachment to the underside of the vehicle engine compartment and provided with an aperture through and extending part way across the undershield, the panel including a deflector on the underside of the undershield and mounted to extend along the leading edge of the aperture in the direction of forward vehicle motion. Such an undershield is shown, for example in CH-A-220080. In this system, an axial fan is located in the engine compartment, the fan drawing air from above the engine and guiding the cooling air through the engine compartment and out through an orifice in the undershield. The orifice is protected from road debris by deflector means. This known cooling system requires incorporation of additional moving parts in the engine compartment to achieve the required cooling. This means the manufacturing and assembly process requires additional steps. Additionally, the deflector means disclosed comprise a series of fins. These fins can be easily damaged by impact with road debris. It is an object of the present invention to overcome these problems. Accordingly, the know system is characterised, in accordance with the invention, in that the deflector is deformable and normally extends downwardly of the undershield in a direction substantially perpendicular to the direction of forward motion whereby to cause a reduction in ambient pressure in the region of the aperture and thereby to cause air to be drawn out of the engine compartment by suction through the aperture. Undershields for protecting the underside of a motor vehicle engine and embodying the invention will now be described by way of example only, with reference to the accompanying diagrammatic drawings in which: Figure 1 is a longitudinal cross-section of one the undershields on line I-I of Figure 2; and Figure 2 is a plan view of the undershield of Figure 1. Figure 1 shows an undershield 1 which protects and shields the underside of a motor vehicle engine, generally shown at 2, from the road surface. The undershield 1 is an arcuately formed panel 7 fixedly attached to the underside of the engine 2 extending from beneath the front of the engine 2a to the rear of the engine 2b. The undershield 1 is formed from thermoplastics material such as polypropylene. The front portion of the undershield 1 is provided with a vent 4 to allow improved air circulation. As shown, the undershield 1 is made of an arcuately formed panel 7. The underside of the panel 7 is provided with a deformable deflector 6 extending widthwise of the panel 7 and which runs alongside the leading edge (in the forward direction of the vehicle) of the vent 4. The top side of the panel 7 is provided with an integrally formed raised protective element 5 extending in the forward direction and acting so as to cover the vent 4. The deflector 6 and the protective element 5 together define protection for the vent 4 in the undershield 1. When the vehicle is moving in the forward direction (arrow A), air flow under the vehicle is deflected by the deflector 6. This causes a reduction in pressure due to the Venturi effect in the region of the vent 4, causing the warm air in the engine compartment to be drawn out in the direction of arrow B thus cooling the engine. The presence of the deflector 6 and the protective element 5 ensures that the engine is still protected from road debris and that contamination of the ground by fluids leaking from the engine is still prevented. However, possible over-heating of the engine compartment caused by the presence of the undershield is reduced by the vent 4. The panel 7 may be formed by injection moulding from a thermoplastics material such as a standard type polypropylene but it will be appreciated that other plastics materials may be used. Subsequently, the deflector 6 may be over-moulded onto the panel 7. Instead of being over-moulded, however it can be formed by any other suitable process. For example, a process can be used by which the deflector from foamed material in the same mould as the panel 7, using a mould with a movable wall portion which is moved outwardly to cause the foaming to take place. As the deflector 6 must be deformable, it is formed from an elastomeric material such as a plastics or rubber material. This produces an undershield 1 resilient to shocks. It will be appreciated that the deflector 6 can be adhesively attached to the panel 7 and need not be over-moulded onto the panel 7.

Claims: An undershield (1) for a motor vehicle engine compartment, comprising a panel (7) for attachment to the underside of the vehicle engine compartment and provided with an aperture (4) through and extending part way across the undershield, the panel (7) includes a deflector (6) on the underside of the undershield (1) and mounted to extend along the leading edge of the aperture(4) in the direction of forward vehicle motion, characterised in that the deflector is deformable and normally extends downwardly of the undershield (1) in a direction substantially perpendicular to the direction of forward motion whereby to cause a reduction in ambient pressure in the region of the aperture (4) and thereby to cause air to be drawn out of the engine compartment by suction through the aperture. An undershield (1) according to claim 1, characterised in that the aperture is unobstructed on the rearward side of the deflector (6). An undershield (1) according to claim 1 or 2, characterised in that the panel (7) is formed by injection moulding. An undershield (1) according to any preceding claim, characterised in that the deflector (6) is over-moulded onto the panel (7). An undershield (1) according to claim 3, characterised in that the deflector (6) is adhesively attached to the panel. An undershield (1) according to claim 3, characterised in that the panel (7) is formed from thermoplastics. An undershield (1) according to claim 3, characterised in that the panel (7) is formed from polypropylene. An undershield according to claim 4, characterised in that the deflector (6) is formed from an elastomer. An undershield according to claim 4, characterised in that the deflector (6) is formed from rubber. An undershield according to any preceding claim, characterised in that the panel (7) includes protector means (5) on the topside of the undershield (1) and mounted along the trailing edge of the aperture (4). An undershield according to claim 10, characterised in that the protector means (5) extends in the forward direction and acts so as to parially cover the aperture (4).

Inventors: DETERRE REMI, KAELBEL OLIVIER, DETERRE, REMI, KAELBEL, OLIVIER
Applicants: DRAFTEX IND LTD, DRAFTEX INDUSTRIES LIMITED
Application year: 1996
Main classification: B62D25
IPC codes: B62D35