Field of the Invention

[001 ] The present invention relates to a wear plate of the type suitable for use in industrial systems such as conveyor systems, transfer chute systems, mills, kilns or crushers.

Background to the Invention

[002] Industrial systems use a range of plates designed to guide material along an intended flow path. Wear plates may be placed at certain locations adjacent a surface provided for supporting material such that material on the surface engages with a front face of the wear plate as it passes the wear plate in order to guide the material. Such wear plates may be located so that one of the edges of the wear plate is located adjacent the surface carrying the material.

[003] In such an arrangement, the edge of the wear plate adjacent the surface will tend to wear over time. The edge of the wear plate will therefore gradually recede away from the surface. As the gap between the edge and the surface increases, larger pieces of the material may move between the edge of the wear plate and the surface. If a sufficiently large piece of material gets wedged between the plate and the surface, it can gouge into the surface and cause significant damage. This damage can be very costly in terms of both replacing the damaged parts and shutdown time for the system.

[004] Monitoring the wear plates for the level of wear is therefore important. Due to the physical arrangement of these plates however, it is often difficult to inspect both the edge and the face for wear without shutting down the industrial system. The present invention relates to a wear plate having features aimed at providing information regarding the level of wear of the wear plate. Summary of the Invention

[005] According to one aspect of the present invention there is provided a wear plate comprising: a body having a front surface, a rear surface and a first edge connecting the front and rear surfaces along first sides thereof; a recess in the rear surface for receiving a sensor unit, the sensor unit having one or more sensor arms extending outwardly therefrom; and one or more channels extending from the recess to the first edge of the body; wherein each sensor arm is received within one of the channels and fixed in position by a corresponding covering member received into the channel such that wearing of the first edge of the wear plate wears down ends of the sensor arms.

[006] Preferably an inner surface of the recess is planar and the sensor unit comprises a planar body received within the recess and secured to an inner surface thereof.

[007] Preferably a plurality of channels are provided at intervals along the length of the first edge of the wear plate.

[008] Preferably inner surfaces of the channels are angled relative to the plane of the wear plate such that distal ends of the channels are located closer to the front surface of the wear plate than proximal ends of the channels.

[009] Preferably of the inner surfaces of the channels are provided at different angles such that the sensor arms are positioned at different orientations.

[010] In one embodiment, inner surfaces of endmost channels on the first edge are oriented at a greater angle than channels located between the endmost channels.

[011 ] Preferably the channels are provided extending from the recess towards a second edge, being opposite the first edge. [012] In one embodiment, the covering members each comprise an elongate member having a shape complementary to the shape of the channel.

[013] Preferably the covering members each include a lower surface having a shape corresponding to an inner surface of the channel and an upper surface having a shape complementary to that of the rear surface of the wear plate adjacent the channel.

[014] In one embodiment, the channels are tapered such that ends of the channels adjacent the first and second edges are narrower than the width of the channels adjacent the recess and the covering members have a corresponding taper such that the covering members may be received into the channels and moved towards the first and second edges such that the covering members are wedged into the channels.

[015] Preferably the covering members are secured into the channels with an adhesive.

[016] Preferably the wear plate is provided with a plurality of apertures extending from the recess through to the front surface to receive further sensor arms such that the further sensor arms extend through the thickness of the body from the rear surface to the front surface to sense wear of the thickness of the wear plate.

[017] Preferably the sensor arms include conductors connectable to circuitry within a housing mounted to the rear surface of the wear plate.

[018] Preferably a mounting post is provided centrally within the recess for mounting of the housing.

[019] Preferably the mounting post includes an outer thread for engagement with the housing and a central bore through which wires may be passed to connect to the conductive tracks.

[020] In one embodiment, the sensor unit comprises a flexible sheet material on which conductive tracks extending along the sensor arms are provided, the sensor arms being able to be flexed and bent such that distal ends thereof can extend outwardly away from the sensor body and may also be bent perpendicular to the plane of the sensor body.

[021] In a further embodiment, the sensor arms comprise conductive tracks printed directly onto the inner surfaces of the recess and channels.

Brief Description of the Drawings

[022] The invention will now be described, by way of example, with reference to the following drawings, in which:

[023] Figure 1 is a rear perspective view of a wear plate in accordance with the present invention;

[024] Figure 2 is rear perspective view of the wear plate of Figure 1 with the covering members removed;

[025] Figure 3a is a rear view of the wear plate of Figure 1 with a sensor unit attached to the rear surface of the wear plate;

[026] Figure 3b is a rear view of the wear plate with the sensor arms extended into the associated channels in the rear surface of the wear plate;

[027] Figure 4a is a perspective view of the sensor unit in the extended configuration;

[028] Figure 4b is a rear perspective view of the wear plate with the sensor unit in place and covering members installed; and

[029] Figure 5 is a transparent view of the wear plate showing the positioning of the sensor arms of the sensor unit.

Detailed Description of Preferred Embodiments

[030] Referring to the Figures, there is shown a wear plate 10 comprising body 12 having a front surface 14 and a rear surface 15. The front surface 14 is provided to engage with material in an industrial system such that the front surface 14 will wear over time. The rear surface 15 is located on a side of the body 12 opposite to the front surface 14. [031 ] In the embodiment shown, the front and rear surfaces 14 and 15 are planar and rectangular in shape. The front and rear surfaces 14 and 15 are connected by opposite first and second edges 16 and 17 and opposite third and fourth edges 18 and 19. While the body 12 of the wear plate 10 is rectangular in the embodiment shown, it will be appreciated that the wear plate 10 may comprise other shapes, depending on the application.

[032] The wear plate 10 is provided with a sensor unit 20. The sensor unit 20 is formed from a material on which a plurality of conductors may be provided. In the embodiment shown, the sensor unit 20 comprises a sensor body 22 formed from a sheet material having the ability to flex and bend and the conductors comprise conductive tracks printed onto a surface of the sensor body 22.

[033] The sensor body 22 includes a plurality of sensor arms 26 each comprising a relatively thin elongate member formed during construction of the sensor body 22 such that the sensor arms 26 are each coplanar with the sensor body 22. In the embodiment shown, a plurality of sensor arms 26 are provided on opposed first and second sides of the sensor body 22.

[034] The material from which the sensor body 22 and the sensor arms 26 are formed allows the sensor arms 26 to flex and to also be bent. The sensor arms 26 may be flexed and bent such that distal ends thereof extend outwardly away from the sensor body 22 and may also be bent perpendicular to the plane of the sensor body 22.

[035] The body 12 of the wear plate 10 includes a recess 28 in the rear surface 15. The recess 28 is located in the embodiment shown generally centrally on the rear surface 15 of the body 12 and extends generally across the width of the body 12 between the third and fourth edges 18 and 19. An inner surface 30 of the recess 28 is generally planar such that the sensor body 22 of the sensor unit 20 may be received within the recess 28 and secured to the inner surface 30.

[036] The body 12 of the wear plate 10 is provided with a plurality of channels

32 extending outwardly from the recess 28. Each of the channels 32 extends from the recess 28 towards one of the edges of the body 12. In the embodiment shown, there are provided a plurality of channels 32 extending from the recess 28 towards the first edge 16 and a plurality of further channels 32 extending from the recess 28 towards the second edge 17.

[037] Each of the channels 32 is provided such that one of the sensor arms 26 may be folded outwardly to be received along the channel 32. The sensor arms 26 contained within the channels 32 therefore extend to the first and second edges 16 and 17 such that wearing of the first and second edges 16 and 17 will result in wearing down of the sensor arms 26. Wearing down of the sensor arms 26 can therefore be used to determine the amount of wear of the first and second edges 16 and 17 of the wear plate 10.

[038] Inner surfaces of the channels 32 in the embodiment shown are angled relative to the plane of the wear plate 10 such that the inner surfaces of the channels 32 are angled slightly towards the front surface 14 of the wear plate 10. The angle of the inner surfaces of the channels 32 may differ such that the sensor arms 26 may be positioned at different orientations. In the embodiment shown, each of the first and second edges 16 and 17 are provided with four such channels 32 where endmost channels, being the channels 32 closest to the third and fourth edges 18 and 19, are oriented at a greater angle than inner channels 32 located between the endmost channels 32. The channels 32 in the embodiment shown are spaced apart at intervals along the lengths of the first and second edges 16 and 17.

[039] The wear plate 10 is provided also with a plurality of apertures 34. The apertures 34 extend from the recess 28 through to the front surface 14 of the body 12 of the wear plate 10. In the embodiment shown, there are provided three such apertures 34 located at spaced intervals along each opposed side of the recess 28. The apertures 34 can receive further sensor arms 26 such that the further sensor arms 26 extend through the thickness of the body 12 from the rear surface 15 to the front surface 14. As the front surface 14 of the wear plate 10 wears down in use, the length of the sensor arms 26 decreases which can be used to sense the amount of wear of the thickness of the wear plate 10. [040] The conductors on the sensor unit 10 are connectable to a processing unit (not shown) including suitable circuitry to detect the wear of the sensor arms 26 and transmits information to a wear monitoring system. The circuitry may be provided in a housing (not shown) mounted to the rear surface 15 of the wear plate 10. In the embodiment shown, a mounting post 36 is provided centrally within the recess 28 for mounting of the housing. The mounting post 36 includes an outer thread for engagement with the housing and a central bore through which wires may be passed to connect to the conductive tracks. More than one mounting post may also be provided. In the embodiment shown, the recess 28 includes raised regions 37 located either side of the central mounting post 36 where further mounting posts may be provided.

[041 ] The wear plate 10 is provided with a plurality of covering members 38, each covering member 38 is provided to be received in one of channels 32. Each of the covering members 38 in the embodiment shown comprises an elongate member having a shape complementary to the shape of the channels 32 such that the covering member 38 may be received in the channels 32 and secured above the sensor arm 26 with an appropriate adhesive. It will be appreciated however that alternative shapes of channels 32 and covering members 38 may be utilised. The covering members 38 thereby secure the sensor arms 26 within the channels 32.

[042] The covering members 38 therefore each include a lower surface 42 having a shape corresponding to an inner surface of the channel 32 and an upper surface 43 having a shape complementary to that of the rear surface 15 adjacent the channel 32.

[043] It will be appreciated that while the sensor unit 20 in the embodiment shown comprises a planar sensor body 22 constructed separately and fixed into the recess 28, channels 32 and apertures 34 in the rear surface 15 of the wear plate, in an alternative embodiment, the sensor unit 20 may be printed directly onto the rear surface 15 in the appropriate locations within the recess 28, channels 32 and apertures 34. [044] The channels 32 in one embodiment are slightly tapered such that ends of the channels 32 adjacent the edges 16 and 17 are narrower than the width of the channels 32 adjacent the recess 28. The covering members 38 have a corresponding taper such that the covering members 38 may be received into the channels 32 and moved towards the edges 16 and 17 such that the covering members 38 are wedged into the channels 38 and may not move outwardly beyond the first and second edges 16 and 17. That is, the covering members 34 include first and second side surfaces 44 and 45, extending between the lower and upper surfaces 42 and 43 where the first and second side surfaces 44 and 45 that angle in toward each other.

[045] In use, the sensor unit 20 is placed within the recess 28 and the sensor arms 26 extended outwardly through each of the channels 32 and downwardly into the apertures 34. The covering members 38 are fixed in place within the channels and further plugs 40 are also inserted into the apertures 34 to secure or the sensor arms 26 in the apertures 34. The wear plate 10 is positioned in use such that one of the edges 16 and 17 is located adjacent a surface on which material is supported for movement, for example the upper surface of a conveyor belt. Over time as the edge 16 or 17 wears down, the distal ends of the sensor arms 26 are also worn down and this change in length is detectable by the wear monitoring system. The wear monitoring system can be set up to alert operators of the system when the edges 16 or 17 of the wear plate 10 are sufficiently worn to require maintenance. The wear plate 10 may therefore be used in an industrial system along with a wear monitoring system to better determine when the wear plate 10 requires maintenance, thereby reducing the risk of damage to the surface by excessive wear.

[046] While the wear plate 10 in the embodiment shown in the drawings comprises a planar plate, it will be appreciated that other shapes for the wear plate 10 may be used, based on the application. For example, the wear plate may comprise a curved or part cylindrical shaped plate. Such curved liner plates may be used, for example, within pipe systems and heavy earth moving systems. [047] It will be readily apparent to persons skilled in the relevant arts that various modifications and improvements may be made to the foregoing embodiments, in addition to those already described, without departing from the basic inventive concepts of the present invention.