AU2008200433B2 - A mud flap - Google Patents

Abstract

A mud flap (100) fabricated from rubber or PVC is disclosed having a planar body (16) and a thickened region (13) at its upper edge (12), by means of which the mud flap is secured to a vehicle. There is a transition zone including a ramp (22) or a radiused taper (29) between the planar body and thickened region. The effect of the transition zone is to diffuse the lines of flexure about which the planar body pivots relative to the thickened region. Longer operating life results. 5232A-AU -8- C\Q ol/ /\- c'4L co .4- 'I, cv/

Description

A MUD FLAP Field of the Invention The present invention relates to mud flaps and, in particular, to mud flaps for heavy 5 vehicles such as trucks, semitrailers, articulated vehicles, and the like. Background Art Conventionally mud flaps are fabricated from either rubber compounds or pliant polymers such as PVC. The mud flap is moulded in a single piece having a generally 10 planar configuration. The body of the mud flap is a pliant sheet which is able to flex and thereby absorb the energy of road spray, mud, rocks and other projectiles thrown from the tyres of the vehicle. Adjacent the upper edge of the mud flap there is a thickened region which is generally 15 rectangular and has a series of apertures which enable the thickened region to be screwed, bolted, or otherwise fastened to the vehicle frame immediately to the rear of (and sometimes additionally also in front of) the corresponding wheel, or wheel set, of the vehicle. 20 Preferably the mud flap also includes moulded logos, names, and like advertising material which indicate the brand of vehicle, the name of the transport company, and so on. A problem with conventional mud flaps is that there is a line of weakness where the 25 generally planar pliant sheet joins to the thickened region and the material of the mud flap flexes at this line of weakness as the mud flap swings forwardly and rearwardly as a consequence of the vehicle's motion. As a consequence, the material of the mud flap fatigues and the mud flap breaks along the line of weakness. 30 Genesis of the Invention The genesis of the present invention is a desire to prolong the operating life of such mud flaps. 5232A-AU Summary of the Invention According to a first aspect of the present invention there is disclosed a mud flap for a vehicle, said mud flap being moulded in a single piece from pliant polymeric material, having a generally planar configuration defined by a pliant sheet having first and 5 second opposite surfaces, and said mud flap having a thickened region adjacent the upper edge of the mud flap, said thickened region having a shape which permits said mud flap to be secured to said vehicle immediately adjacent one of the wheels thereof by means of fasteners or the like with said first surface adjacent said wheel, wherein said second surface ha a raised peripheral rim and at least one indicium sized to be 10 viewed from behind said vehicle, and there is a transition zone on said second surface interconnecting said thickened region and said pliant sheet, said transition zone having a thickness intermediate that of said thickened region and said pliant sheet. Brief Description of the Drawings 15 Two embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which: Fig. 1 is a perspective view of a prior art mud flap, Fig. 2 is a similar perspective view of the mud flap of the first embodiment, Fig. 3 is a cross-sectional view taken along the line III-Ill of Fig. 1, 20 Fig. 4 is a cross-sectional view taken along the line IV-IV of Fig. 2, and Fig. 5 is a cross-sectional view similar to Fig, 4 but of a second embodiment. Detailed Description A prior art mud flap 10 is seen in Fig. 1 and has a lower edge of 11 and an upper edge 25 12. At the upper edge 12 is a rectangular thickened region 13 which has two (or more in many instances) apertures 14 which enable the mud flap 10 to be secured by means 2 5232A-AU of fasteners such as bolts, rivets, etc. to a vehicle (not illustrated) immediately behind one of the wheels of the vehicle. The mud flap 10 is moulded in a single piece from rubber, PVC, or other similar 5 polymeric material which is sufficiently pliant to enable the mud flap 10 to flex as indicated by arrow A in Fig. 1. The mud flap 10 is moulded to have a pliant planar body 16 and a peripheral rim 17 which extends therearound. Adjacent the lower edge 11 is positioned a mould insert to enable a logo 18 (which in this instance takes the form of the letter T), or similar, to be moulded into the mud flap 10. The longitudinal 10 extent of the mud flap 10 (that is to say the distance between the upper edge 12 and lower edge 11) differs for different mud flaps and is illustrated in Fig. 1 as having an indefinite extent. The width of the mud flaps can also vary. As best seen in Figs. 1 and 3, there is an abrupt transition between the rectangular 15 thickened region 13 and the planar body 16 in the form of a wall of 19 which is substantially perpendicular to the planar body 16. As a consequence, since the thickened region 13 is rigidly held to the frame of the vehicle, the front to rear swinging motion of the mud flap 10 induced by the motion of 20 the vehicle takes place about the line of weakness W-W illustrated by broken lines in Fig. 1. Therefore the material of the mud flap 10 fatigues along this line thereby causing the planar body 16 to eventually be ripped from the thickened region 13 as the fatigued material of the mud flap 10 fails. This necessitates replacement of the mud flap 10. 25 Turning now to Fig. 2, the mud flap 100 of a first embodiment is illustrated. Those components of the mud flap 100 which are the same as the mud flap 10 are designated with like designation numbers. The most substantial change is that related to the transition between the thickened region 13 and the planar body 16. In the mud flap 30 100, a number of ramps or wedges 22 are provided which extend between the upper surface of the planar body 16 and the upper surface of the thickened region 13. In this particular embodiment there are seven ramps 22A-22G, however, the number of ramps 22 can be changed in different embodiments. In addition, as seen Figs. 2 and 4 5232A-AU 3 the ramps 22 are provided with different slope angles and different inclined lengths. Adjacent ramps 22 preferably abut but need not do so. A consequence of the different extent of the various ramps 22A-22G is that the planar 5 body 16 flexes relative to the thickened region 13 along a number of different lines of flexure Fl - Fl to F3 - F3 as schematically illustrated in Fig. 2. In general, the number of different lines of flexure will be equal to the number of different ramp extents. It will be appreciated from Figs. 2 and 4 that the material of the planar body 16 which is located at the commencement of the ramp 22B flexes as the planar body 10 16 swings relative to the thickened region 13. However, this material is not adjacent to the material of the planar body 16 which is located at the commencement of ramp 22A and which also flexes as the planar body 16 swings. As a result, material in which fatigue occurs in one portion of the planar body 16 is non-aligned with, and is not immediately adjacent to, material of another portion of the planar body 16 which 15 also becomes fatigued. As a consequence, despite this fatigue, the planar body 16 of the mud flap 100 does not rip along a single line of weakness as occurs with the mud flap 10. Substantially extended operating life is the result. An additional feature of the mud flap 100 is that the thickened region 13 is provided 20 with apertures 24 which are not centrally spaced in the thickened region 13 but instead are located closer to the ramps 22 than to the upper edge 12. This arrangement makes the thickened region 13 less likely to tear as a result of vertically downwardly directed forces being applied to the mud flap 100. 25 Turning now to Fig. 5, here a second embodiment of a mud flap 200 is illustrated in which the transition from the planar body 16 to the thickened region 13 is provided by means of a radiused taper 29. As a consequence, the flexing between the planar body 16 and the thickened region 13 takes place over a more diffuse zone for the mud flap 200 than for the mud flap 10. 30 The foregoing describes only two embodiments of the present invention and modifications, obvious to those skilled in the transportation arts, can be made thereto without departing from the scope of the present invention. For example, instead of a 5232A-AU 4 single radiused taper 29, a number of different tapers each of different radius can be provided. Similarly, the edge between the rim 17 and the adjacent wedges 22A and 22G is preferably bevelled or radiused as illustrated in Fig. 2 to provide a more durable transition between the rim and the wedges. 5 Furthermore, the mud flap 100 can be extruded by removing the two vertical portions of rim 17 (and the lower horizontal portion of rim 17, if desired). The extrusion emerges sideways from the mould and only a single wedge 22 or taper 29 is provided. 10 In a further embodiment, the wedges 22 can be replaced by sinusoidal, scalloped or castellated protrusions. The term "comprising" (and its grammatical variations) as used herein is used in the inclusive sense of "including" or "having" and not in the exclusive sense of 15 "consisting only of'. 20 25 30 5232A-AU 5

Claims (7)

1. A mud flap for a vehicle, said mud flap being moulded in a single piece from pliant polymeric material, having a generally planar configuration defined by a pliant sheet having first and second opposite surfaces, and said mud flap having a thickened region adjacent the upper edge of the mud flap, said thickened region having a shape which permits said mud flap to be secured to said vehicle immediately adjacent one of the wheels thereof by means of fasteners or the like with said first surface adjacent said wheel, wherein said second surface has a raised peripheral rim and at least one indicium sized to be viewed from behind said vehicle, and there is a transition zone on said second surface interconnecting said thickened region and said pliant sheet, said transition zone having a thickness intermediate that of said thickened region and said pliant sheet.

2. The mud flap as claimed in claim I where said transition zone comprises at least one taper.

3. The mud flap as claimed in claim 2 wherein the or each said taper comprises a ramp or wedge.

4. The mud flap as claimed in claim 3 having a plurality of said ramps, at least some of which have different angles of inclination.

5. The mud flap as claimed in claim 4 wherein at least some of said ramps extend along said pliant sheet by different extents.

6. The mud flap as claimed in claim were in said transition zone comprises at least one radiused taper.

7. A mud flap for vehicles, said mud flap being substantially as herein described with reference to Figs. 2 and 4 or Fig. 5 of the drawings. Dated this 16th day of January 2014 TRANSCOM INDUSTRIES PTY LIMITED By FRASER OLD & SOHN Patent Attorneys for the Applicants -6-