AU2008200433A1

AU2008200433A1 - A mud flap

Info

Publication number: AU2008200433A1
Application number: AU2008200433A
Authority: AU
Inventors: Stephen Clarence Langham
Original assignee: TRANSCOM IND Pty Ltd
Current assignee: TRANSCOM INDUSTRIES Pty Ltd
Priority date: 2007-02-01
Filing date: 2008-01-30
Publication date: 2008-08-21
Anticipated expiration: 2028-01-30
Also published as: NZ565505A; AU2008200433B2; AU2008200433C1

Description

00 A MUD FLAP Field of the Invention t The present invention relates to mud flaps and, in particular, to mud flaps for heavy 0 5 vehicles such as trucks, semitrailers, articulated vehicles, and the like.

SBackground 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 oc 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 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.

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 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.

Genesis of the Invention The genesis of the present invention is a desire to prolong the operating life of such mud flaps.

5232A-AU 00 Summary of the Invention 0 According to a first aspect of the present invention there is disclosed a mud flap for a heavy vehicle, said mud flap being moulded in a single piece from pliant polymeric Cmaterial, having a generally planar configuration defined by a pliant sheet, and having a thickened region adjacent the upper edge of the mud flap, said thickened region being shaped to permit said mud flap to be secured to said vehicle immediately to the Cc rear of one of the wheels thereof by means of fasteners or the like, wherein there is a C€3 transition zone interconnecting said thickened region and said pliant sheet.

00 10 According to a second aspect of the present invention there is disclosed a method of extruding a mud flap having a generally planar body and a thickened region at one (,i (upper) edge thereof, said method comprising the steps of: selecting the cross-section of said mud flap along a line substantially perpendicular to said thickened region to be of uniform shape, (ii) providing a transition zone between said planar body and said thickened region and including same in said uniform shape, (iii) forming an extrusion mould to have said uniform shape, and (iv) extruding said mud flap.

Brief Description of the Drawings 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-III of Fig. 1, 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 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 5232A-AU 0 of fasteners such as bolts, rivets, etc. to a vehicle (not illustrated) immediately behind one of the wheels of the vehicle.

CThe mud flap 10 is moulded in a single piece from rubber, PVC, or other similar C 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 Sform of the letter or similar, to be moulded into the mud flap 10. The longitudinal 00 10 extent of the mud flap 10 (that is to say the distance between the upper edge 12 and 0 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 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 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 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 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 0the ramps 22 are provided with different slope angles and different inclined lengths.

Adjacent ramps 22 preferably abut but need not do so.

CA consequence of the different extent of the various ramps 22A-22G is that the planar O 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 00 10 16 swings relative to the thickened region 13. However, this material is not adjacent Sto 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 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 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.

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 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 00 single radiused taper 29, a number of different tapers each of different radius can be 8 provided. Similarly, the edge between the rim 17 and the adjacent wedges 22A and N22G is preferably bevelled or radiused as illustrated in Fig. 2 to provide a more Ctdurable transition between the rim and the wedges.

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 e¢3 emerges sideways from the mould and only a single wedge 22 or taper 29 is provided.

00 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 "consisting only of'.

5232A-AU

Claims

1. A mud flap for a heavy vehicle, said mud flap being moulded in a single piece Nfrom pliant polymeric material, having a generally planar configuration t defined by a pliant sheet, and having a thickened region adjacent the upper Oedge of the mud flap, said thickened region being shaped to permit said mud flap to be secured to said vehicle immediately to the rear of one of the wheels thereof by means of fasteners or the like, wherein there is a transition zone interconnecting said thickened region and said pliant sheet.

2. The mud flap as claimed in claim 1 where said transition zone comprises at 00 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.

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 1 were in said transition zone comprises at least one radiused taper.

7. A mud flap for heavy vehicles, said mud flap being substantially as herein described with reference to Figs. 2 and 4 or Fig. 5 of the drawings.

8. A method of extruding a mud flap having a generally planar body and a thickened region at one (upper) edge thereof, said method comprising the steps of: selecting the cross-section of said mud flap along a line substantially perpendicular to said thickened region to be of uniform shape, (ii) providing a transition zone between said planar body and said thickened region and including same in said uniform shape, (iii) forming an extrusion mould to have said uniform shape, and (iv) extruding said mud flap.

9. The method as claimed in claim 8 wherein said thickened region is generally rectangular and said transition zone comprises a radiused taper. 5232A-AU -6- A method of extruding a mud flap, said method being substantially as herein described. Dated this 25th day of January 2008 TRANSCOM INDUSTRIES PTY LIMITED By FRASER OLD SOHN Patent Attorneys for the Applicants 5232A-AU