AU5366000A - Protective shroud - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Protective Shroud The following statement is a full description of this invention, including the best method of performing it known to me: FIELD OF THE INVENTION The following invention relates to a shroud to protect the leading edge of the digging implement of a front end loader, an excavator, or similar vehicle. Typically, such shrouds are positioned in between adjacent cutting teeth mounted at the front edge of the loader or excavator blade. The front edge of the blade requires protection against the abrasive impact of earth, rocks, ore and other material as the blade is forced into and across the earth by the heavy pushing vehicle. The invention might also relate to the protection of a leading edge of a digging implement such as those mentioned above, though not including cutting teeth. The invention also relates to such protective shrouds as might be mounted to the leading edge of the sidewalls of a front end loader bucket for example.

A problem with known shrouds is that they are prone to working loose of the blade and possibly becoming completely detached therefrom. If a shroud becomes detached in a mining situation, it can be collected with the ore and/or dirt and inadvertently delivered to an ore crusher. The damage resulting to the crusher from the detached shroud is serious and expensive to repair, resulting in some cases in complete shutdown of the mine facility.

Another problem with known shrouds is that they must usually be formed from a material capable of being readily welded. Suchpmaterials ofte displaypoor wear Documents received on: 9 18 AU t6 2000 Batch Ne: ii characteristics and therefore present a compromise in design performance.

It is known to secure shrouds to the leading edge of the loader or excavator blade using bolts which pass through vertical holes drilled near the leading edge of the blade. This system may compromise the structural integrity of the blade itself and does not securely fasten the shroud to the blade over the useful working life of the vehicle itself.

Another known system of securing a shroud to a loader or excavator blade is to weld a 10 boss to the upper surface of the blade near its leading edge, to place the shroud over the boss and to insert a locking device into an aperture on the upper surface of the shroud so as to cooperate with the boss. This known system is susceptible to movement of the shroud upon the blade which results in wear to the mating surfaces of the shroud, lock and boss and possible subsequent detachment of the shroud in the field.

OBJECT OF THE INVENTION It is the object of the present invention to overcome or substantially ameliorate at least 20 one of the above disadvantages and/or more generally to provide an improved shroud to protect the leading edge of loader and excavator blades and the like.

DISCLOSURE OF THE INVENTION There is disclosed herein a shroud for protecting a leading edge of a blade, the blade having an upper surface from which there extends a boss having a substantially horizontal aperture extending in a direction normal to said leading edge, the shroud comprising: a slot into which a portion of the leading edge of the blade is receivable, a bolt cavity to receive and support a horizontal bolt, such that thread of the bolt can pass through said aperture to receive a nut, tightening of which will draw the shroud toward the boss such that the slot bears onto to the blade.

Preferably, the bolt is a mill liner bolt which has a tapered surface portion.

Preferably, the bolt cavity includes a tapered surface against which the tapered surface portion of the bolt can bear.

Preferably, the bolt cavity includes an opening through which the bolt can pass laterally to be received within the bolt cavity.

S1 Preferably, the shroud further includes a recess sized and shaped to at least partly fit over the boss on the upper surface of the blade.

Preferably, the nut is received within the recess.

Preferably, the shroud includes a tapered leading edge.

Preferably, the shroud is sized and shaped to fit between adjacent teeth secured to the blade.

Alternatively, the shroud is sized and shaped to fit upon and protect the vertical leading edge of a sidewall of a front end loader bucket or a shovel. In this case, the "blade" is the sidewall.

DEFINITIONS

As used herein, the term "blade" is intended to mean any part of an excavator bucket or the edge of a shovel or any other component to be forced into or over the ground for excavating, mining or earth moving purposes, that would be subjected to wear at its leading edge. This leading edge would generally extend horizontally in use, but might extend in another orientation such as vertically, where the "blade" is the sidewall for example of a shovel or bucket.

As used herein, the term "horizontal" is intended to mean an in-use orientation that is substantially at right angles to the vertical.

As used herein, the phrase "upper surface" is intended to mean that surface of the "blade" that faces inwardly, ie. toward the load carrying area of the shovel or bucket.

Where the leading edge of the blade extends horizontally, which is the normal case, the phrase "upper surface" therefore means that surface of the blade which faces 10 generally upwardly in use. Where the blade is a sidewall of a bucket or shovel, the "upper surface" actually faces sideways toward the centre of the shovel or bucket where load is carried.

:Furthermore, any other phrases such as "vertical", "downwardly facing" and like expressions are intended to refer to the in-use orientation of the shroud.

."BRIEF DESCRIPTION OF THE DRAWINGS A preferred form of the present invention will now be described by way of example 20 with reference to the accompanying drawings wherein: Figure 1 is a schematic inverted partial plan view of a shroud; Figure 2 is a schematic cross-sectional elevational view of the shroud of Figure 1 taken at A-A in Figure 1; Figure 3 is a schematic rear elevational view of the shroud of Figures 1 and 2; Figure 4 is a schematic end elevational view of a bolt; Figure 5 is a schematic side elevational view of the bolt of Figure 4; and Figure 6 is a schematic cross-sectional partial view of the leading portion of a blade, having a boss welded thereto and showing the association of the boss with a bolt used to secure the shroud.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the accompanying drawings; there is schematically depicted a shroud 10. Shroud is typically formed from rolled alloy. The shroud 10 includes a leading edge 11 and an upper surface 13 within which there is provided a transverse longitudinal slot 12 into which the leading edge of a loader or excavator blade is received.

Also beneath the upper surface 13 there is provided a bolt cavity 14 including a downwardly facing opening 16 through which a bolt 18 can be vertically inserted in a 10 horizontal orientation into the cavity 14. Alongside the opening 16 there is provided a recess 15 into which the end of the bolt extends to receive a washer 25 and a nut 26.

The bolt cavity 14 includes an oval shaped conical bearing surface 17 which is situated just above the opening 16. The type of bolt to be received within the bolt cavity 14 is shown in Figures 4 and 5. This type of bolt 18 is otherwise known as a 15 mill liner bolt for use in the lining of a grinding mill. The bolt 18 includes a threaded shank 19 and a head 20 delimited from the shank 19 by an oval-shaped conical ramp S"portion 21. It is this portion which bears against the bearing surface 17 within cavity 14. That is, the threaded shank 19 is presented to the left in Figure 1 so as to extend into the recess 15. This recess is sized and shaped so as to fit over a boss 22 which is 20 welded to the upper surface of the loader or excavator blade 23. This boss has a horizontally extending aperture 24 extending in the travel-direction of the vehicle and through which the threaded shank 19 can pass to enable a washer 25 and nut 26 to be fitted thereon within the recess 15. Tightening of the nut 26 will draw the bolt 18 toward the boss such that the ramped surface 21 bears tightly against the bearing surface 16 to draw the shroud back over the leading edge 27 of the blade 23 which would be wedged tightly within the slot 12 due to it acutely angled internal surfaces.

An advantage of the invention disclosed herein is that the shroud can be installed as an after market addition to an existing loader or excavator blade. That is, a number of bosses 22 can be welded to the upper surface of the blade in positions in between the positions at which the cutting or digging teeth are mounted to the blade. That is, the blade need not be drilled to accommodate any vertically extending bolt. Furthermore, the nut can be tightened with a conventional socket and can be re-tightened if necessary should the shroud become loose through wear in the field.

It should be appreciated that modifications and alterations obvious to those skilled in the art are not to be considered as beyond the scope of the present invention. For example, the bolt cavity 14 could be redesigned to accommodate a different type of bolt.

10 It should also be appreciated that the protective shroud disclosed herein can be sized and shaped so as to be received upon any edge requiring protection from abrasive wear. Such an edge need not be the leading edge of a loader or excavator blade as it might be the leading edge of a sidewall of a front end loader bucket or the leading edge of any implement to be pushed into, so as to dig or otherwise manipulate a oo 15 ground surface or even an underwater surface such as in dredging equipment. For example the leading edge might be upon a shovel. Such a protective shroud might *"even be used in a mechanical plant where say a flow of abrasive material along a conveyor belt or other path requires division into two separate paths. A vertically extending dividing blade in such an arrangement might require protection and the S. 20 shrouds as disclosed herein might be equally applicable thereto.

Claims (10)

1. A shroud for protecting a leading edge of a blade, the blade having an upper surface from which there extends a boss having a substantially horizontal aperture extending in a direction normal to said leading edge, the shroud comprising: a slot into which a portion of the leading edge of the blade is receivable, a bolt cavity to receive and support a horizontal bolt, such that thread of the bolt can pass through said aperture to receive a nut, tightening of which will draw the shroud toward the boss such that the slot bears onto to the blade.

2. The shroud of claim 1 wherein the bolt is a mill liner bolt which has a tapered ~surface portion.

The shroud of claim 2 wherein the bolt cavity includes a tapered surface 15 against which the tapered surface portion of the bolt can bear.

4. The shroud of claim 1 wherein the bolt cavity includes an opening through which the bolt can pass laterally to be received within the bolt cavity. 20

5. The shroud of claim 1 further including a recess sized and shaped to at least partly fit over the boss on the upper surface of the blade.

6. The shroud of claim 5 wherein the nut is received within the recess.

7. The shroud of claim 1 including a tapered leading edge.

8. The shroud of claim 1 being sized and shaped to fit between adjacent teeth secured to the blade.

9. The shroud of claim 1 being adapted to fit in a vertical orientation to the leading edge of a sidewall of a front end loader bucket or a shovel, the shroud being 8 sized and shaped to fit upon and protect said leading edge. A shroud substantially as hereinbefore described with reference to the accompanying drawings. DATED this 28th day of August 2000 CUTTING EDGES PTY LIMITED Patent Attorneys for the Applicant:

10 HALFORD CO