AU724758B2 - Rock ejector for a vehicle - Google Patents

Description

<l P/00/011 Regulation 3.2

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT 0* a Name of Applicant: Address of Applicant: Actual Inventor: Address for Service: D.G. FREEMAN 2855 Helena Valley Road Helena Valley, Western Australia Australia 6056 D.G. Freeman Griffith Hack, 256 Adelaide Terrace (6th Floor), Perth, Western Australia, Australia 6000 a a.

a.

a a

S*O*

Standard Complete Specification for the invention entitled: ROCK EJECTOR FOR A VEHICLE Details of Associated Provisional Applications: PN 8296 filed 26 February 1996.

The following is a full description of this invention, including the best method of performing it known to me:- 2 ROCK EJECTOR FOR A VEHICLE The present invention relates to a rock ejector for a vehicle of a type having two or more wheels at opposite ends of an axle.

Many transport and earth moving vehicles are provided with two adjacent (ie. dual) wheels at the opposite ends of one or more of their axles. It is a well known problem in the operation of such vehicles that rocks or other debris becomes trapped or caught between the tyres of dual wheels 10 which leads to the puncturing, shredding or other catastrophic failure of the tyres.

°o In an attempt to alleviate this problem, it is known to sometimes place circular discs between adjacent wheels in an attempt to prevent rocks and other debris from being caught between the wheels. While such discs are successful to a degree, they are inconvenient to install as they require the addition of mountings on or between the wheels.

Additionally, their inclusion greatly increases the time taken to service the wheel (and associated tyre) to which 20 they are connected. This is because of the need to remove the disc from the mountings on the wheel.

Another form of rock ejector is known which is in the form of an elongate bar fixed to the body of a dump truck. The bar extends substantially vertically between adjacent tyres. However, as the body of the dump truck and the axle uponwhich the wheels are mounted are able to move relative to each other, the elongate bar can at times rub on the tyres and cause as much damage as rocks themselves.

It is an object of the present invention to provide a rock ejector which when installed causes minimal damage to the wheels between which it is placed. It is a secondary object to provide a rock ejector which when installed allows easy and convenient access to both of the wheels to in which it is placed.

According to the present invention there is provided a rock ejector for a vehicle having a chassis and an axle coupled to said chassis, said axle provided at one end with two or more wheels arranged side by side, said rock ejector including: an arm supported by said chassis and extending between said wheels, said arm is supported in a manner so as to allow said arm to move between said wheels in a direction substantially parallel to the length of said axle, whereby, in use, a rock or other debris picked up between said wheels will contact said arm and be thereby ejected from between said wheels.

Preferably said arm is pivotally supported about an axis extending substantially perpendicular to said axle to facilitate the movement of the arm.

Preferably an end portion of said arm which extends between said wheels is smoothly curved so as to minimise damage to *"*either one of said wheels in the event of contact between said one end and said wheels.

Preferably said end portion is formed in the shape of a substantially spherical ball.

Preferably said arm is in the form of a plate lying in a plane substantially perpendicular to said axle and at least S"in part, reducing in width towards said one end.

Preferably a smoothly curved projection extends from opposite sides of said arm for substantially centring said arm between said wheels.

4 Preferably an edge of said arm is orientated in a manner so that when a rock or other debris caught between said wheels strikes said edge, said rock or other debris is directed by said edge toward an outer periphery of said wheels so as to be ejected from between said wheels.

Preferably said arm is supported by a suspension system of said vehicle, said suspension system being coupled to said chassis and said axle being coupled to said suspension system.

10 An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawings in which: Figure 1 Figure 2 Figure 3 Figure 4 is a schematic representation from the side of two rock ejectors in accordance with the present invention shown in relationship with two wheels of a vehicle; is a top view of four rock ejectors with an associated mounting member; and, is a top view of a chassis of a vehicle to which the rock ejectors and mounting member of Figure 2 are attached; and, is a schematic representation from the side of a second embodiment of a rock ejector.

Referring to the accompanying drawings, and in particular, Figure 3, there is shown a plurality of rock ejectors for a vehicle (not shown) having a chassis 12 and two axles 14 and 16 coupled to the chassis 12. A pair of wheels 18 with associated tyres is rotatably mounted at each end of each of the axles 14 and 16. The vehicle is also provided with a suspension system 20 which is coupled between the chassis 12 and axles 14 and 16.

Each rock ejector 10 is disposed between a respective pair 1"

L

of wheels 18. The rock ejectors 10 comprise an arm 22 which is supported either by the chassis 12 or the suspension 20 and has one end 24 which extends between the wheels 18. Each arm 22 is supported in a manner so as to allow it to move in a plane substantially parallel to the axle on which is mounted the wheels 18 between which the arm 22 extends. This movement is provided for by pivotally supporting an opposite end 26 of the arm 22 about an axis 28 which extends substantially perpendicular to the corresponding axle 14 or 16, as the case may be. Thus, the arm 22 is hinged about an axis extending substantially vertically.

End 24 of each arm 22 is smoothly curved to minimise damage to the tyres in the event of mutual contact. Most convenient, the end 24 is smoothly curved by forming it in the shape of a spherical ball As is most apparent from Figures 2 and 3, each arm 22 is in the form and shape of a tapered plate which is disposed to ".lie in a plane perpendicular to the axle 14 or 16 of the wheels between which it is disposed. The tapered plate *reduces in width toward end 24. Additionally, each side of *'.the arm 22 is provided with a smoothly curved projection 32 which assists in substantially centering the ejector between the wheels 18. The projection 32 can be in the form of a semi-cylinder (ie. a cylinder cut along its longitudinal axis) and attached to the arm 22 with its longitudinal axis substantially perpendicular to the axles 14 and 16 and the flat side of the semi-cylinder connected with the arm 22. In an alternate arrangement, the projection 32 can be semi-spherical in shape. By having the projection 32 smoothly curved, there is minimal contact area between the projection and the side walls of the tyres of wheels 18 thus minimising wear or other damage to the tyres.

6 An edge 34 of arm 22 is orientated so that when a rock or other debris caught between the wheels 18 strikes the edge 34, the rock or other debris is directed by the edge toward the outer periphery of the wheels 18 so as to be ejected.

This is shown most clearly in Figure 1 in which the wheels 18 rotate in a clockwise direction when the vehicle (not shown) is driven forward. With reference to the wheel on axle 16, it will be appreciated that a rock caught between a pair of the wheels 18 when striking the edge 34 will be effectively rolled along the edge 34 by the rotation of the wheels themselves so as to be ejected from between the wheels. Similarly, with the wheels 18 on axle 14, a rock ~lodged therebetween will impact on edge 34 and again be rolled by the action of the rotating wheels 18 so as to be o o 15 directed towards the outer periphery of the. wheels and thereby be ejected.

In general, the above effect is achieved by shaping or configuring the edge 34 so that, in the 'direction of rotation of the wheels 18, end 24 lies on a radius which is 20 in advance of the radius of a point of the edge 34 adjacent the outer periphery of the wheel 18. This is graphically illustrated in Figure 1 for the rock ejector 10 between the wheels 18 rotatably mounted on the axle 14. The wheel 18 moves in a clockwise direction as indicated by arrow A.

Point P1 of edge 34 is located near end 24 and lies on radius R1. Point P2 on edge 34 is located adjacent the periphery of wheel 18 and lies on radius R2. When the wheel 18 is moved in the clockwise direction shown by arrow A, the radius R1 along which point P1 lies is in advance of radius R2 along which point P2 lies.

Referring again to Figures 2 and 3, it can be seen that four rock ejectors 10 are pivotally connected to an elongate mounting member in the form of a bar 36. The mounting bar 36 is itself attached to the suspension system 7 of the vehicle (not shown). The mounting bar 36 extends parallel to and lies between the axles 14 and 16 so that each of- the rock ejectors 10 is disposed between corresponding pairs of the wheels 18.

As the mounting bar 36 is connected to the suspension it is able to move in a similar manner to the axles 14 and 16 and accordingly substantially maintain the relative positions of the rock ejectors 10 and the wheels 18.

However, variations in the positions can be compensated for 10 by virtue of the ejectors 10 being able to pivot about pivot axis 28. The ability to generally maintain the relative position of a rock ejector 10 and the wheels 18 is 9 9also achieved, though to a lesser extent, by mounting the *999 ejector 10 or corresponding mounting bar to the chassis 12.

It will be appreciated that if an inner one of the wheels 18 requires servicing, the adjacent front wheel can be removed in the normal way and the ejector 10 pivoted about :axis 28 so as to allow free and complete access to the •inner wheel.

20 A second and somewhat simplified version of the rock S'.i ejector.is shown as item 10' in Figure 4. The rock ejector differs from the rock ejector 10 shown in Figures 1-3 by the exclusion of the spherical ball 30 and projections 32. Further, the longitudinal edges 34' are curved instead of being straight as in the first embodiment. Finally, the mounting bar 36' now has a compound profile composed of a rectangular section 38 and collinearly circular section extending along a lower horizontal edge.

Now that an embodiment of the invention has been described in detail, it will be apparent to those skilled in the relevant arts that numerous modifications and variations may be made without departing from the basic inventive concepts. For example, the projections 32 and/or the 8 spherical ball 30 may be omitted from the ejector 10 or replaced with projections or portions of different shape which achieve the same effect. Also although edge 34 of the arm 22 has been illustrated as being straight, it can be curved or of otherwise arcuate shape. Further, the rock ejector 10 is applicable to any vehicle having two or more adjacent wheels at the end of axle irrespective of how many axles the vehicle is provided with or the use of the vehicle. All such modifications and variations are deemed to be within the scope of the present invention, the nature of which is to be determined from the foregoing description.

*oo• ***oo

Claims (9)

1. A rock ejector for a vehicle having a chassis and an axle coupled to said chassis, said axle provided at one end with two or more wheels arranged side by side, said rock ejector comprising at least: an arm supported by said chassis and extending between said wheels, said arm is supported in a manner so as to allow said arm to move between said wheels in a direction substantially parallel to the length of said axle, whereby, in use, a rock or other debris picked up between said wheels will contact said arm and be thereby ejected from between said wheels.

2. A rock ejector according to claim 1, wherein said arm is pivotally supported about an axis extending substantially perpendicular to said axle to facilitate the movement of the arm.

3. A rock ejector according to claim 2, wherein an end portion of said arm which extends between said wheels is smoothly curved so as to minimise damage to either one of *said wheels in the event of contact between said one end and said wheels.

S4. A rock ejector according to any one of claims 1 to 3, wherein said end portion is formed in the shape of a substantially spherical ball. .30

5. A rock ejector according to claim 4, wherein said S arm is in the form of a plate lying in a plane substantially perpendicular to said axle and at least in part, reducing in width towards said one end.

6. A rock ejector according to any one of claims 1 to wherein a smoothly curved projection extends from opposite sides of said arm for substantially centring said arm between said wheels.

7. A rock ejector according to any one of claims 1 to 6, wherein an edge of said arm is orientated in a manner so that when a rock or other debris caught between said wheels strikes said edge, said rock or other debris is directed by said edge toward an outer periphery of said wheels so as to be ejected from between said wheels.

8. A rock ejector according to any one of claims 1 to 7, wherein said arm is supported by a suspension system of said vehicle, said suspension system being coupled to said chassis and said axle being coupled to said suspension system.

9. A rock ejector substantially as herein described with reference to and as illustrated by the accompanying drawings. Dated this 1 2 t h day of July 2000. D.C. FREEMAN By His Patent Attorneys: 25 GRIFFITH HACK Fellows Institute of Patent and Trade Mark Attorneys of Australia. oo 0