MOTOR VEHICLE BODY COMPRISING MUDGUARDS ARRANGED TO SCREEN AT LEAST SOME OF THE VEHICLE WHEELS

Abstract: The motor vehicle body is provided with mudguards (2) having screening surfaces (4) disposed peripherally about the relative wheel (3) and is characterised in that each of said surfaces is provided with a plurality of side-by-side ribs (6), each of which extends from the laterally more outer edge (7) to the laterally more inner edge (8) of the surface and each of which is inclined in such a manner as to be directed both towards said laterally more inner edge and in the opposite direction to the direction of the tangential velocity with which that surface zone of the wheel lying below said rib rotates when the vehicle is running.

Description: This invention relates to a motor vehicle body, and in particular an industrial vehicle body, comprising mudguards arranged to screen at least some of the vehicle wheels. When a vehicle runs on wet ground, and in particular when the vehicle speed is fairly high, large quantities of water are displaced by each wheel with the result that the aerodynamic action created by the air flow grazing the vehicle body forms a water-in-air suspension which completely surrounds the vehicle body, particularly in the zone closest to the wheels. In this respect, most of the water displaced by the wheels is projected by centrifugal action against the mudguard inner surface, which then directs the striking air flow in various directions to result in intense mixing of the water with the air to form the said suspension. Large quantities of water-in-air suspension moving with the motor vehicle are known to be particularly annoying and dangerous to drivers of other vehicles because of the considerable water quantity projected on to such vehicles and the considerable kinetic energy thereof. The object of the present invention is to provide a motor vehicle body which obviates the aforesaid drawback by substantially reducing, in particular in the vehicle wheel region, the quantity of water-in-air suspension which is formed when the vehicle runs on wet ground. This object is attained by a motor vehicle body comprising mudguards arranged to screen at least some of the vehicle wheels, each of said mudguards having screening surfaces disposed peripherally about the relative wheel, characterised in that each of said screening surfaces is provided with a plurality of side-­ by-side ribs, each of which extends from the laterally more outer edge to the laterally more inner edge of the surface and each of which is inclined in such a manner as to be directed both towards said laterally more inner edge and in the opposite direction to the direction of the tangential velocity with which that surface zone of the wheel lying below said rib rotates when the vehicle is running. The present invention will be more apparent from the detailed description thereof given hereinafter by way of example with reference to the accompanying drawings, in which: Figure 1 is a perspective view of the front part of a heavy motor vehicle body constructed in accordance with the present invention; Figure 2 is a plan view of the body part of the preceding figure; Figure 3 is a diagrammatic perspective view of a mudguard of the body of the preceding figures and the relative wheel; Figure 4 is a perspective view of a mudguard and the relative wheel corresponding to a different embodiment of the invention. The vehicle body of the invention, of which only part is shown in Figures 1 and 2, is particularly suitable for use in a heavy vehicle, but can be suitable for any other vehicle, for example an automobile. Said vehicle body, indicated overall by the reference numeral 1, comprises mudguards 2, each of which is arranged to screen a corresponding vehicle wheel 3. Each mudguard comprises a plurality of screening surfaces 4 (Figures 3 and 4) defined by the inner surfaces of the mudguard walls 5. As shown in Figures 3 and 4, said walls can be more than one in number and can be of any shape. In the illustrated case, which relates to an indus­ trial vehicle body, each mudguard comprises a pair of walls 5 of different shape and dimensions, as can be clearly seen in the figures. According to the invention, each screening surface 4 is provided with a plurality of side-by-side ribs 6, each of which extends from the laterally more outer edge 7 to the laterally more inner edge of the relative surface. In addition, each of said ribs is inclined in such a manner as to be directed both towards the laterally more inner edge 8 and in the opposite direction to the direction of the tangential velocity with which that wheel surface zone lying immediately below the rib rotates when the vehicle is running. Consequently, in the case of the mudguard ribs of Figures 3 and 4, it is assumed that the normal running direction causes the wheels to rotate in an anti-clockwise direction, and that the said tangential velocity is therefore represented by vectors lying on the outer wheel surface and directed in the said anti-clockwise direction. Conveniently said ribs are either rectilinear, as in the embodi­ ment shown in Figure 3, or are curved. Helical ribs such as those shown in Figure 4 have proved particularly suitable. Conveniently each of the screening surfaces 4 can comprise ribs 6 forming a different angle to the direction of the tangential velocity of the wheel 3. In the embodiment shown in Figure 4, substantially three different screening surfaces can be identified, in that that wall 5 of the mudguard 2 to the left in Figure 4 comprises substantially a pair of screening walls 4a, 4b, the first of which is curved whereas the second is substan­ tially flat, and that wall 5 of the mudguard lying to the right in Figures 3 and 4 comprises one screening surface 4c, which is curved. Consequently in the embodiment shown in Figures 3 and 4, the screening surfaces 4a and 4c can comprise side-by-side ribs 6 having substantially the same inclination to the said tangential velocity direction, whereas the ribs of the screening surface 4b can have a different inclination, for example less than the inclination of the ribs provided on the other two screening surfaces. Conveniently, the width of each rib 6 can vary in passing from the peripherally more outer edge 7 to the peripherally more inner edge 8, or the height of each of said ribs can vary in passing from one to the other of the two said edges. In this manner the cross-section of the channel defined between two adjacent ribs can vary in passing from the laterally more outer edge 7 to the laterally more inner edge 8. Said ribs can either be formed integrally with the material with which the walls 5 of the mudguard 2 are constructed, or can be provided on support elements 9 which are then fixed to the mudguard walls 5. In this second case, said support elements are conveniently constructed of thermoplastic material. If the vehicle body of the invention comprises a driver's front cab 10, of the type shown in Figures 1 and 2, the body thus being of an industrial vehicle, said cab will comprise two side surfaces 11 and a front surface 12. In this case, according to the invention, each of said side surfaces is connected to the front surface by a connection zone 13, the minimum radius of which is greater than 100 mm. As will be more apparent hereinafter, it has in fact been found that a connection radius of the said value results in the favourable effects described hereinafter. The behaviour of the described vehicle body when in operation is as follows. When the vehicle travels along a wet road, in particular at fairly high speed, large quantities of water are lifted by each vehicle wheel 3, most of which is projected by centrifugal action against the screening surfaces 4a, 4b, 4c of each mudguard 2. Because of the presence of the ribs 6, the water which strikes said surfaces is not projected in other directions to form a water-in-air suspension as happens in the case of vehicle bodies provided with mudguards of normal type, but instead is substan­ tially conveyed into the channels formed between adjacent ribs 6. As said channels are directed substantially towards the periphe­ rally inner edge 8 of each mudguard, this water is discharged towards the centre of the vehicle frame and thus into a zone at which the water falls to the ground substantially in the centre of the vehicle. It has been found that in addition to preventing subsequent rebounding of the water flow which strikes the inner surfaces of the mudguard, the ribs 6 convey the flow towards the central zone of the vehicle, to thus prevent formation of a large quantity of water-in-air suspension outwards from the sides of the vehicle. By suitably choosing the size of said ribs it is substantially possible to discharge into the indicated zone most of the water which is lifted by the wheels. In addition, if the rib width or height varies between the laterally more outer edge 7 and the laterally more inner edge 8, the channels formed by the ribs can have a useful cross-section, for the purposes of water discharge, which varies in the direction of the channel axis and thus varying water speeds and throughputs along each of said channels can be obtained to give more effective water discharge through the channels. It has also been found that the effect which favours the prevention of a large quantity of water-in-air suspension being formed to the side of the vehicle is considerably enhanced if the radius of curvature of the connection zone 13 between the side surfaces 11 and front surface 12 of the vehicle body is chosen as stated heretofore. In this respect, if this radius is suffici­ ently large, namely greater than the stated value, the air flow which laterally grazes each side wall surface 11 is not deviated substantially from the surface but grazes along it. The resultant air stream moving along each side wall of the vehicle prevents the formation of vacuum in the zone between each mudguard 2 and wheel 3 which would tend to prevent regular water movement in the aforesaid direction through the channels defined by the ribs 6. If the connection radius is less than the stated value, the air stream tends to separate from the surfaces 11 with the result that a suction effect can be generated causing some obstacle to regular water movement. It is apparent that modifications can be made to the described embodiments of the present invention but without leaving the scope of the invention idea. In particular, although a heavy vehicle body has been considered, the inventive concept can be applied to a vehicle body of any other type, for example of an automobile. Furthermore, although the inventive concept has been applied and described with reference to a vehicle front mudguard, it can be applied to the rear mudguard, with the described beneficial effects being substantially unchanged in the case of the vehicle rear mudguards provided they have the structure described with reference to the front mudguards.

Claims: 1. A motor vehicle body comprising mudguards (2) arranged to screen at least some of the vehicle wheels, each of said mudguards having screening surfaces (4) disposed peripherally about the relative wheel (3), characterised in that each of said screening surfaces (4) is provided with a plurality of side-by-­ side ribs (6), each of which extends from the laterally more outer edge (7) to the laterally more inner edge (8) of the surface and each of which is inclined in such a manner as to be directed both towards said laterally more inner edge and in the opposite direction to the direction of the tangential velocity with which that surface zone of the wheel lying below said rib rotates when the vehicle is running. 2. A vehicle body as claimed in claim 1, characterised in that said ribs (6) are rectilinear. 3. A vehicle body as claimed in claim 2, characterised in that said ribs (6) are curved. 4. A vehicle body as claimed in claim 3, characterised in that said ribs (6) are helical. 5. A vehicle body as claimed in one of the preceding claims, characterised in that each of said screening surfaces (4) comprises ribs (6) which form a different angle to the direction of said tangential velocity. 6. A vehicle body as claimed in one of the preceding claims, characterised in that the width of each of said ribs (6) varies in passing from said peripherally more outer edge (7) to said peripherally more inner edge (8). 7. A vehicle body as claimed in one of the preceding claims, characterised in that the height of each of said ribs (6) varies in passing from said peripherally more outer edge (7) to said peripherally more inner edge (8). 8. A vehicle body as claimed in one of the preceding claims and defining a driver's front cab (10) provided with at least one pair of lateral side-wall surfaces (11) and a front surface (12), characterised in that each of said lateral surfaces is connected to said front surface by a connected zone (13) the minimum radius of which exceeds 100 mm. 9. A vehicle body as claimed in one of the preceding claims, characterised in that said ribs (6) are formed integrally with the material with which the mudguard walls are constructed. 10. A vehicle body as claimed in one of the preceding claims, characterised in that said ribs (6) are provided on support elements (9) fixed to the mudguard walls. 11. A vehicle body as claimed in claim 9, characterised in that said support elements (9) are constructed of plastics material.

Inventors: SAVIO, PIERO
Applicants: IVECO FIAT S.P.A.
Application year: 1987
Main classification: B62D25
IPC codes: B62D25