AU2006202446A1 - A rim assembly - Google Patents

Description

Page 1 of 7 A RIM ASSEMBLY IP Australia AUG 2006 Field of the Invention I The present invention relates to a rim assembly and, in particular, to a rim assembly for wheels of a mining shuttle car.

Background of the Invention In fields such as the mining industry, shuttle cars are used to transport coal underground. These shuttle cars are approximately 20 to 30 tonnes in weight and usually have four to six wheels. Each wheel typically includes a tyre mounted to a rim which is secured to a hub of the vehicle. A typical mining tyre is pressurised and a pre-mounted spring loaded locking assembly locks the tyre to the rim. A series of wheel stud lug bolts are utilised to secure the rim to the hub. The locking assembly typically consists of a rim base, a spring locking ring and continuous side rings or flanges. These parts are designed to allow the spring locking ring to fit into a gutter on the base rim, locking the flange in place on the rim when the tyre is inflated. The spring locking ring is continuous except for a gap of about 10 mm. The gap accommodates a pry bar to assist in assembly/disassembly as the ring is spring loaded. When the tyre is inflated, the removable flange is pushed against the spring locking ring.

If the alignment is not correct or too much pressure is used, the locking assembly can blow apart by way of the spring locking ring and flange separating from the rim base with a violent force. This can also occur during use, when dirt or wear builds up, the pressure in the tyre is too great or the torque used to tighten the lug nuts is excessive.

Further, damaged or mismatched rim parts, the rim base gutter and the rim flange Page 2 of 7 containing corrosion and dirt buildup or the locking ring being deformed or sprung open prior to use, will also cause the assembly to blow out.

The above explosions can be extremely dangerous. When the locking assembly fails, the wheel rim violently hurls parts of the rim outwardly in all directions due to the pressure build up within the tyre. This will not only damage parts of the shuttle car or sensitive componentary within the mine, a mine worker can be hit by flying debris. In fact, a number of workers have been killed and seriously injured during the assembly/fitting of such tyres.

It has been found that the principle hazard in the removal, assembly and inflation 1o of wheels in the mining industry is that of the spring loaded locking rings. All the systems presently utilised are sprung by using a split ring and held in place by the pressure of the tyre.

Object of the Invention It is an object of the present invention to overcome or ameliorate some of the disadvantages of the prior art, or at least to provide a useful alternative, such as a total safety feature of a locking device.

Page 3 of 7 Summary of the Invention There is firstly disclosed herein a rim assembly including: a generally cylindrical rim defining an axis and including: an annular longitudinally extending base; an annular bead retaining lip extending in a generally radial and longitudinal direction from one axial end of said base; and an annular flange fixed to an opposite axial end of said base and defining a radially longitudinally extending annular channel between said base and flange; a pair of removable semicircular securing members operatively associated with said rim to circumferentially surround said channel, said securing members in use having ends adjacent to one another, and fastening means adapted to urge the ends of said securing members together bringing said securing members into locking engagement with each other about said rim.

Preferably, said securing members include an annular protrusion to abut against a complimentary edge of said flange.

Preferably, each end of said securing members includes a hole adapted for receipt of a respective said fastening means.

Preferably, said fastening means includes a threaded fastener.

Page 4 of 7 Preferably, said fastening means includes a bar and set screw combination.

Preferably, including a series of apertures spaced radially about the circumference of said flange.

Preferably, each said securing member includes an aperture alignable with a corresponding aperture of said flange and adapted for receipt of a threaded fastener to align said flange and securing member together.

Preferably, the width of said securing member is greater than the width of said channel.

Brief Description of the Drawings A preferred embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, wherein: Figure 1 is a top view of a rim assembly in- accordance with an embodiment of the present invention showing a bolt on flange arrangement; Figure 2 is a sectional view along the line 2-2 of Figure 1; Figure 3 is a partial sectional view along the line 3-3 of Figure 1; Figure 4 is a plan view of an embodiment of the securing members of the present invention; Figure 5 is a cross-sectional view along the line 5-5 of Figure 4; Page 5 of 7 Figure 6 is an enlarged view of one side of the rim assembly shown in Figure 2; and Figure 7 is a side view of the assembly of an embodiment of the present invention showing the assembly procedures.

Detailed Description of the Preferred Embodiments Referring to the drawings, there is disclosed herein a rim assembly 1 for securing a tire (not shown) to a rim 5 of a vehicle (not shown). The rim assembly 1 includes a generally cylindrical rim 5 defining an axis X as best seen in Figures 2 and 7. The rim includes an annular longitudinally extending base 10. An annular bead retaining lip extends in a generally radial and longitudinal direction from one axial end of the base An annular flange 20 is fixed to an opposite axial end of the base 10 and defines a radially longitudinally extending annular channel 25 between the base 10 and flange 20 as best seen in Figure 6.

In use, the tyre of a vehicle is locatable about the base 10 with the corresponding beads abutting the lip 15 and flange 20. As shown in Figures 2 and 6, the base 10 can also include a valve slot 32 so that the valve of the tyre can be accessed externally of the rim 5. The tyre is secured to the rim 5 by way of a pair of removable semi-circular securing members 30. The securing members 30 are operatively associated with the rim to substantially circumferentially surround the channel 25. In a preferred form, the width of the securing members 30 is greater than the width of the channel 25 however this does not need to be the case in all embodiments. The securing members 30 have ends adjacent to one another as best seen in Figure 4. Each end 35 of the securing members Page 6 of 7 include at least one hole or aperture 37 for receipt of a respective fastening means The fastening means 40 are adapted to secure or urge the ends 35 of the securing members 30 together bringing the securing members 30 into locking engagement with each other about the rim 5. In the preferred form, the fastening means 40 includes a flat s bar 45 and a pair of set screws 50 however any other typical fastening combination could be utilised. The securing members 30 can also include apertures 53 for alignment with corresponding apertures 55 in the flange 20. The apertures 55 spaced radially about the circumference of the flange 40. The securing members 30 also include an annular protrusion 60 to abut against a complimentary edge 65 of the flange Steps for manufacturing the rim assembly 1 of the present invention can include the rim 5 having a champher or edge 65 machined as shown in Figure 6. Cast Steel bolt on Flange 20 (material BS 3100 GR A) is then welded to rim 5 preferably by a submerged arc welding procedure. Holes 55 are then drilled in the annular flange 20 as shown Figure 1. Locking flanges or securing members 30 are typically made from cast steel BS 3100 GR Al. These are machined in a full circle as shown Figure 5. A recess is milled for locking tab or bar 45 to sit flush with the locking flange 30. The locking rings or securing members 30 are then split as shown in Fig 7. Locking tabs or bars 45 are drilled and countersunk, then joined by two allen cap head screws 50 typically made from stainless steel. Locking ring halves (flanges or securing members) 30 are then split and fitted to rim 5 by way of locking tab or bars 45 as shown in the figures.

In use, the method of assembly/disassembly of the rim assembly I includes the removal of locking tabs or bars 45. Split locking rings or securing members 30 are then removed sideways away from the rim 5. A tyre is then fitted to rim 5, locking flanges or Page 7 of 7 securing members 30 re-fitted and joined by locking tab or bars 45. Rim 5 and tyre are c then ready for filling or air inflation.

Advantageously, the present invention provides a safe and effective way of securing a tyre to a rim of a vehicle and in particular for mining machinery. As the securing members are not spring loaded there is a substantial reduction in the chances of the rim exploding and a user being injured. Though the invention has been specifically directed towards mining shuttle cars, it should be understood that the rim assembly could be utilised on any vehicle in any field.

Although the invention has been described with reference to specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms.