Screen panels for ore sorting machines are well known and generally comprise a screen body which defines a screening area which may include apertures for enabling material for a particular size to pass through the apertures to thereby separate material of that size from material of a greater size.

Australian patent application 43524/99 discloses a screen modular panel system which includes modular panels which have a resiliently deformable attachment flange at opposite ends of the screen panel. The panel is connected to an attachment rail by arranging two of the panels in side by side relationship with attachment flanges adjacent one another. A locking member is driven between the two panels to cause the attachment flanges to deform about the attachment rail to thereby couple the panels to the attachment rail, and therefore couple the panels to the screening machine.

The content of Australian patent application no. 43524/99 is incorporated into the this specification by this reference.

The attachment rails in the aforesaid Australian application comprise rail flanges which are inclined to the vertical and have an inclined inner surface about which the attachment flange is deformed to secure the panels to the rail, and an outer inclined surface which defines the outer periphery of the attachment rail. When the panels are to be engaged with the rail the panels are located on the rail so that the attachment flange sits over the rail flange with part of the body of the panel

being adjacent to the outer inclined surface of one of the rail flanges. It has been found that when a number of such panels are to be installed in a screening machine one of the panels, upon securement to an attachment rail by the aforesaid locking member, can cause the panel to move laterally so that that panel abuts another panel which has already been engaged with an attachment rail. Movement of the other panel causes the part of the panel which is adjacent the outer incline surface of another attachment rail to ride up that inclined surface on that attachment rail which may cause disengagement of the panel from the attachment rail.

The object of a first aspect of the invention is to overcome this problem.

The invention in a first aspect may therefore be said to reside in an attachment rail for securing a screen modular panel to a screening machine, the panel having deformable attachment flanges and at least one flat surface portion on the panel adjacent each attachment flange and inwardly of the attachment flanges, the attachment rail including ; at least one rail flange having an inclined attachment surface for receiving one of the attachment flanges of the panel so the attachment flange can be deformed around the rail flange to attach the panel to the screening machine ; and at least one flat surface portion on the attachment rail for abutment with the at least one flat surface portion on the panel to prevent the panel from riding up on the rail when another said panel is being attached to the screening machine.

Thus, if the panel is moved laterally by another panel during engagement of the other panel with the machine, the abutment of the flat surface portion of the panel with the flat surface portion of the attachment rail will hold the

panel in place rather than simply allowing the panel to ride up the attachment rail. Thus, panels which are already installed in the machine are not dislodged by engagement of other panels, because of the abutment of the flat surface portion of the panel with the flat surface portion of the rail.

Preferably the outer surface of the attachment flange is inclined and generally parallel to the attachment surface of the rail flange, the flat surface portions being generally vertical walls formed by cut-outs in the outer surface of the rail flange.

Preferably the attachment flange includes a plurality of said flat surface portions and each panel having three flat surface portions which abut three of the flat surface portions of the rail.

Preferably each rail has two rail flanges. However, the outer most rail for arrangement at an edge of the screening machine includes a single rail flange having the inclined attachment surface.

This aspect of the invention may also be said to reside in a modular screen panel for a screening machine, the screening machining having attachment rails which include lateral extending rail flanges and at least one flat surface portion formed on an outer surface of the rail flange, said panel including; a screen module body having laterally extending ends and longitudinally extending ends bordering a screening region; an attachment flange on each of the laterally extending ends or the longitudinally extending ends of the module body; the attachment flanges being deformable for deforming around one of the rail flanges so that each

attachment flange can engage behind one of the flanges to attach the module to the screening machine; and at least one flat surface portion on the screen module for abutting the flat surface portion on the attachment rail to prevent the panel from riding up on the attachment rail if the panel is subject to a force tending to move the panel towards the attachment rail during securement of other screen panels to the screening machine.

Preferably the screen panel has at least one reinforcing member extending between the attachment flanges, the flat surface portion of the panel being formed on the reinforcing member inwardly of the attachment flange.

Preferably the panel includes at least three reinforcing members extending between the attachment flanges, each reinforcing member having a said flat surface portion at each end adjacent to and inwardly of a respective attachment flange.

This aspect of the invention also provides a screening assembly for a screening machine including; a screen module including a screen module body having laterally extending ends and longitudinally extending sides bordering a screen region; a resiliently deformable attachment flange disposed at the laterally extending ends or the longitudinally extending ends of the screen module; an attachment rail having at least one rail flange, the rail flange having an inclined attachment surface ; the attachment flange being locatable over the rail flange and deformable so as to deform around the rail flange so that the attachment flange engages behind the attachment surface to attach the modular panel to the screening machine;

a flat surface portion formed on the screen module adjacent to each attachment flange and inwardly of each attachment flange ; a flat surface portion formed on an outer surface of the attachment rail so that the flat surface portion of the panel lies adjacent the flat surface portion of the attachment fail when the panel is located on the rail flange; and wherein if the panel is subject to any lateral force pushing the panel towards the attachment rail the flat surface portion of the panel abuts the flat surface portion of the rail flange to prevent the panel from riding up on the rail flange.

A further aspect of the invention is concerned with coupling of the panels to the attachment rails of the screening machine.

As is disclosed in the aforesaid Australian patent application, in order to attach the panels, two panels are arranged on an attachment rail in side by side relationship and an elongate locking member is hammered between the panels so as to force the attachment flanges to deform about the rail flanges and locate behind the inclined attachment surfaces of the attachment rail.

Because the attachment flanges extend for the entire length of one side of the panel a considerable amount of force may be required in order to make the flanges deform and this can require considerable effort to hammer the locking member between the panels.

A second aspect of the invention is directed at overcoming this problem.

The invention, in a second aspect may be said to reside in a modular screen panel for a screening machine, the screening machine having attachment rails which include

laterally extending rail flanges each having an inclined attachment surface, the panel including ; a screen module body having laterally extending ends and longitudinally extending ends bordering a screening region; an attachment flange on each of the laterally extending ends or the longitudinally extending ends, the attachment flange being deformable so as to deform around one of the rail flanges so that the attachment flange engages behind the attachment surface to attach the module to the screening machine; the attachment flanges being formed in a plurality of segments by cuts extending transverse to the longitudinal direction of the attachment flanges so that each segment of the attachment flange on each module can deform independently of the remaining segments to thereby enable each segment to separately and independently deform about the rail flange.

Since the attachment flange is divided into segments the amount of force required to make each separate segment deform around the rail flange is much less than the entire attachment flange thereby making it much easier to hammer the holding member between adjacent rails to thereby secure the panels to the screening machine.

Preferably each attachment flange is divided by the plurality of cuts into six separate segments.

Preferably the panel includes at least one flat surface portion for engaging a corresponding flat surface portion of the attachment rail to prevent the panel from riding up on the attachment rail when another said panel is being coupled to the machine.

Preferably the at least one flat surface portion of the panel is formed on at least one reinforcing member

extending between the ends of the panel having the attachment flanges.

Preferably the panel has three reinforcing members, each reinforcing member having a said flat surface portion at each end of the reinforcing member inwardly of the attachment flange, so that when the attachment flange is seated over the one of the rail flanges of the attachment rail, the flat surface portion at the end of the reinforcing member lies adjacent the corresponding flat surface portion of the rail so that if the panel is moved towards the rail the flat surface portion of the rail and the flat surface portion of the panel abut to prevent the panel from riding up on the rail.

Preferably the panel includes a central reinforcing member which extends between attachment flanges, the cuts dividing both portions of the rail flange on each side of the reinforcing member into the plurality of segments.

This aspect of the invention may also be said to reside in a screening assembly including the said screening panel and a said attachment rail and a holding member for location between a pair of adjacent panels to cause deformation of the attachment flanges about rail flanges of the attachment rail to thereby secure the panels to the screening machine.

Preferred forms of the present invention will now be described by way of example with reference to the accompanying drawings wherein: Figure 1 is a plan view of a screen module.

Figure 2 is an inverse plan view of the screen module of Figure 1.

Figure 3 is a plan view of a screening assembly including four screen modules.

Figure 4 is a plan view of the screening assembly

of Figure 3 with the screen modules in a partly assembled unlocked state.

Figure 5 is a partial cross section of a partly assembled screening assembly.

Figure 6 is a partial cross section of an assembled screening assembly.

Figure 7 is a partial cross section of a partly assembled screening assembly with an alternative locking member, in its unlocked state.

Figure 8 is a partial cross section of an assembled alternate screening assembly.

Figure 9 is a view of an attachment rail used in the preferred embodiment of the invention; Figure 10 is a view of a panel according to the preferred embodiment of the invention showing the panel from beneath; Figure 11 is a cross-sectional view along the line X-X of Figure 10 but showing the cross-section in the proper orientation (that is inverted from the position shown in Figure 10); and Figure 12 is a view showing engagement of the panel of Figure 10 with the attachment rail of Figure 9.

Figures 1 and 2 are plan and inverse plan views of a screen module 1. Figure 3 depicts a screen assembly including four of the screen modules 1 locked onto the frame (not shown) of an existing screening machine, whilst Figure 4 depicts the screen modules located on the screening machine but in an unlocked position. The screen modules 1 are preferably made from a urethane material.

The screen modules 1 each have a screen module body with laterally extending ends and longitudinally extending sides bordering on a screen region (not shown) which may have different sized meshes depending on the desired application. For example, the screen region may have large holes or may be used as a weir without holes at all.

Further, the"screen region"may be fitted with other

equipment such as flow deflectors. It is preferred that the screen region is substantially flat, however there may be applications where the screen region is curved. The surface of the screen region may be made of polyurethane and/or rubbers of various durometers and properties, ceramic tiles cast in urethane, stainless steel wedge wire and perforated steel plate, depending on the application.

Reinforcement members 7a and 7b typically extend along the ends and sides, respectively, of the screen module body.

Further central laterally extending reinforcement members 7c may be provided at predetermined spacings between the end reinforcement members 7a. A central longitudinally extending reinforcement member 7d may be positioned between the side reinforcement members 7b. The various reinforcement members are not depicted in hidden detail in Figure 4 for clarity purposes.

As depicted in Figure 5, at least one end of the screen module 1 is provided with a resiliently deflectable, laterally extending and downwardly projecting module attachment flange 16. The attachment flange 16 has an outwardly facing flange surface 9 which protrudes downwardly and outwardly with respect to the screen region such that it defines an obtuse included angle with the adjacent upper surface of the module body. The attachment flange 16 is cantilevered to the end of the module body.

The flange 16 has an inwardly facing flange surface 24 which defines a downwardly opening recess 21 with an outwardly facing surface 25 of the module body end.

The attachment flange 16 may extend laterally along substantially the entire end of the module body, ending short of the module body sides to allow for the side reinforcement members 7b to extend to adjacent the end of the screen module. In the preferred embodiment depicted, the flange 16 is interrupted midway along the end of the

screen module to allow for the central longitudinally extending reinforcement member 7d, thus forming two separate flange portions arranged along the end of the module body.

A laterally extending attachment rail 3 having a laterally extending base 19 is fixed to, or integrally formed with a laterally extending frame member 2 of the screening machine. Attachment rails 3 are typically bolted in various locations to the laterally extending frame members 2. The attachment rail 3 has laterally extending attachment rail flange 5 projecting upwardly from the base 19 at an acute angle, which is here approximately 60°. The flanges 5 have inclined attachment surfaces 18.

The rail 3 may be provided with a metal reinforcing core 6 with a polyurethane body which forms the rail 3 being moulded about the reinforcing core 6. Similarly, reinforcing elements may also be provided in the panels 1 as is well known.

Screen modules to be positioned in the central area of the screening machine away from the machine edges will typically be provided with a flange 16 at each end of the module body, with the flanges 16 of longitudinally adjacent screen modules being locked onto a common attachment rail 3 with a common locking member 10. Such an attachment rail 3 is provided with two attachment rail flanges 5, each projecting upwardly toward the opposing flange.

Figures 4 and 5 depict longitudinally adjacent screen modules 1 located on a common attachment rail 3 prior to locking. The attachment rail flanges 5 are each received in the recess 21 of the corresponding screen module 1.

The inwardly facing flange surface 24 is typically disposed substantially at right angles to the module body

upper surface when the flange is in the undeflected state such that the flange 16 can be located over the attachment rail flange without the application of excessive force as is required of typical prior art screening assemblies.

When each end of the screen module 1 is provided with a flange 16, with each end being located on an attachment rail 3, the flanges 16 and attachment rails 3 are spaced such that the module 1 can be located onto the attachment rails 3 with the upper end 5a of the attachment rail flanges 5 received in the top of the recesses 21. In the preferred embodiment with the inwardly facing flange surface 24 oriented at right angles to the module body upper surface, the lower edge 24a of the inwardly facing flange surface 24 will lightly contact the upper end 5a of the corresponding attachment rail flange 5 when the screen module 1 is placed in position onto the attachment rail 5.

The inwardly facing flange surface 24 will then slide along the upper end 5a of the rail flange 5 until the module is located in position.

Rather than having the inwardly facing flange surface 24 at right angles to the module body upper surface, the inwardly facing flange surface 24 could be inclined outwardly such that the lower edge 24a did not contact the attachment rail flange during the locating process.

Alternatively, the inwardly facing flange surface 24 could be inclined slightly inwardly by a few degrees such that the lower edge 24a lightly engages the attachment rail flange upper end 5a, requiring light downward pressure, typically applied with an operators hand or foot, to deflect the flanges 16 outwardly to ride over the attachment rail flange upper end 5a and snap into position adjacent the attachment rail flanges 5. Whilst some prior art screening modules require a large force to locate the module into position, which position is the same as the

locked position, with that locating force being proportional to the maximum force the assembly can withstand without failure or disconnection of the module, the force used to locate the current screen module has no bearing on the service loads the assembly can successfully withstand.

To lock the screen module 1 into place, the flange outwardly facing surface 9 is engaged by a locking member 10 to deform the flange 16 into a locked position (as depicted in Figure 6) so that the flanges 16 engage beneath the attachment surface 18 of the rail flange 5.

The flange 16 is securely held in the deformed position between the surface 18 and the member 10 by the member 10.

With the flange surface 24 bearing against the sloped surface of the attachment rail flange 5, a component of the bearing force locking the module end flange 16 onto the attachment rail flange 5 acts vertically downwardly to positively hold the screen module 1 down rather than relying on vertical frictional forces as do some prior art interference fitting systems.

The bearing force locking the module end flange 16 acts over an extended lateral distance and over the height of the inwardly facing flange surface 24 to reduce the bearing stresses on the module end flange 16 and attachment rail flange 5, enabling the locking mechanism to withstand large service loads. Shear forces acting on the flange 16, which can result in failure of pin and lug type prior art systems and other known contoured flange systems, also act over a large area so as to reduce the shear stress levels for a given service load. The upper end 5a of the rail attachment flange is preferably smoothly contoured so as to reduce any possible stress concentrations.

The flange 16 is preferably resilient compressible, made

from a material such as polyurethane or rubber, such that it is compressed by the wedging force, thereby helping prevent loosening of the locking relationship and helping create a self sealing system. The flanges 16 can also be strengthened with materials such as ceramic particles or fibreglass fibres. The modules can be readily unlocked by removing the locking member 10, allowing the screen modules 1 to be simply lifted out of position.

The outwardly facing surface 9 is preferably provided with one or more grooves 17 which engage corresponding projections 29 provided on the engaging surface of the locking member 10, thereby helping maintain the locking member 10 in engagement with the module end flange 16, preventing any possible tendency for the locking member 10 to pop our of engagement. Alternatively the outwardly facing surfaces 9 could be provided with projections on the locking member provided with corresponding grooves.

The recess 21 defined by the inwardly facing surface 24 and the outwardly facing surface 25 of the module body end preferably substantially encases the rail attachment flange 5 when the module end flange is in the locked position as depicted in Figure 6. The screen module 1 thus bears against both sides of the attachment rail flange 5, increasing the rigidity of the connection between the module 1 and attachment rail 3. The module body end outwardly facing surface 25, need not, however bear against the attachment rail flange 5. Having a recess 21 protruding into the thickness of the screen module 1 for receiving the attachment rail flange 5 to define the module end flange 16 helps keep the installation to a minimal thickness, rather than having the flange depend from the bottom of the screen module 1 which will increase the thickens of the installation.

The preferred locking member is formed as a laterally

extending strip 10 which may extend up to the width of the screening machine fame to lock down several screen modules positioned side by side, or may be shorter in length such that each locking trip 10 only extends across one module 1. The locking strip 10 will typically need to be hammered into position inserted between adjacent screen modules 1, and can be removed via the locking strip head lOa which typically extends onto the upper surface of the adjacent screen modules 1. The head lOa can be of varying shapes. The laterally extending locking strip 10 helps seal the interface between adjacent modules from the ingress of fines which can quickly wear attachment rails and machine frames in some prior art systems. A modification depicted in Figure 8 to further inhibit the ingress of fines, involves the provision of a groove 22 or projection on the upper surface of each screen module 1 adjacent the end of the screen region which engages a corresponding projection 23 or groove provided on the screen region which engages a corresponding projection 23 or groove provided on the underside of the head 10a of the locking strip 10. The projection 23 will typically be slightly larger than groove 22 to provide an interference fit improving the seal created.

Some areas of the screening machine, particularly under exciter beams may provide little clearance for swishing hammers an the like for securing the locking strip 10. In such areas, an alternate locking member 10'may be utilised. The alternate locking member 10'is in the form of a cam key 10'having a generally elliptical form which can be inserted between the adjacent module end flanges 16, as depicted in Figure 7, without significant application of force and then turned through 90° so as to forcibly engage the flange outwardly facing surfaces 9, thereby deflecting the module end flanges 16 into the locked positioned wedge against the attachment rail flanges 5. Turning the cam key 10'through 90° again will

unlock the flanges 16.

The projections 29'on the cam key 10'extend around its periphery and engage the grooves 17 in the module end flange outwardly facing flanges surfaces 9 so as to keep the cam key 10'in the correct plane as it rotated, ensuring the cam key does not tilt or pop out. The size of the projections 29'may increase in the region of the periphery engaging the grooves 17 when the can key 10'is rotated to the locked position so as to have a wedging effect on the grooves 17, preventing the cam key 10'from rotating when it has reached the locked position.

Alternatively, grooves could be provided on the cam key 10'an projections on the flange 16.

Figure 9 is a perspective view of the attachment rail 3 according to the preferred embodiment of the invention.

As can be seen from Figure 9, the attachment rail 3 includes a plurality of notches 8 formed in each of the rail flanges 5 notches 8a are also defined by step shoulder portions at the end of the rail flanges 5. The notches 8 accommodate the reinforcing members 7b and 7d of a panel when the panel is engaged with the rail 9.

As can be seen in Figure 8 the rail flanges 5 have an inclined outer surface 15a and portions of the panels will contact the outer surface 15a when the panels are engaged with the respective rail flanges 5 in the manner previously described. Typically, ends of the reinforcing members 7b and 7d are the portions of the panels which engage the outer surface 5a.

After one panel has been engaged with a rail flange 5 in the manner previously described so that the perspective attachment flange 16 has been deformed about the rail 5, the location of another panel in the screening machine at

another part of the screen deck of the screening machine may cause the aforesaid panel to be moved in the direction of arrow A in Figure 9. This movement is created by the force which tends to push the panel laterally side ways to some distance upon insertion of a locking member 10 between two adjacent panels. If the panel engaged with the rail is moved in the direction of arrow A then contact of the ends of the reinforcing members 7b and 7d on the inclined surface 5a of the rail 9 can cause those portions of the panel to ride up the inclined surface as the panel is pushed in the direction of arrow A. This can cause the panel to become disengaged from the rail flange 5 thereby separating the panel from the attachment rail 3.

In order to prevent this from happening the rail 3 is provided with a plurality of cut-outs 120 which generally register and are in line with the notches 8 and 8a. It should be understood that cut-outs 120 are provided on both sides of the attachment rail 3 although, of course, only those on one side can be seen in Figure 9.

The cut-outs 120 define flat surface portions 122 which extend generally vertically and which are boarded by lateral side triangular surface sections 123.

A detailed view of one end of a panel 1, according to another embodiment of the invention, which includes attachment flange 16 is shown in Figure 10.

As can be seen in Figure 10 central reinforcing member 7d extends up to end edge la of the panel 1 and divides the attachment flange 16 into portions 16a and 16b. The portions 16a and 16b are divided into segments 16a'and 16b'by transverse cuts 125 which extend through the flange 16. The purpose of the cuts 125 will be described in more detail hereinafter.

Portion 7d'of the central reinforcing member 7d which divides the flange 16 into the portions 16a and 16b is integral with the remainder of the reinforcing member 7d and a flat surface portion 130 is provided inwardly of the attachment flange 16 and which extends, when the panel is in its correct orientation on a screening machine, downwardly from the portion 7d'to lowermost face 7d''of the reinforcing member 7d. Thus, a step is defined by the flat surface portion 130 between the portion 7d'and 7d'' of the central reinforcing member 7d.

Reinforcing members 7b which are integral with longitudinal sides 132 of the panel 1 are also provided with flat surface portions 131.

The panel 1 preferably has a plurality of reinforcing ribs 135 which extend parallel to the reinforcing members 7b and 7d and cross-reinforcing ribs 143 which extend transverse to the those ribs. Apertures 150 which, in the embodiment shown, are in the form of slits are provided in the upper surface of the panel for the screening of material.

As is best shown in Figure 12, when the panel 1 is located on rail 3 the portion 7d'of the reinforcing member 7d and the portion 7b'of the reinforcing member 7b locate in notches 8 one of the rail flanges. This enables the attachment flange 16 to seat over the rail flange 5. When the panel is so located on the rail 3 the surfaces 131 and 130 lie closely adjacent to the surfaces 122 formed by the cut-outs 120. Thus, any tendency to push the panel in the direction of arrow A in Figure 9 will result in the surfaces 130 and 131 abutting hard up against the surfaces 122 which will prevent the panel from riding up the incline surface 15a of the rail flange 5. Thus, the panel is held properly in place on the rail 3 and will not dislodge due to unwanted upward movement caused by any

tendency to force the panel in the direction arrow A in Figure 9.

The cuts 125 which divide the attachment flange, and in particular the portions 16a and 16b in the segment 16a' and 16b'increases the ease by which the attachment flange 16 can engage with a rail flange 5 and be deformed to sit behind the rail flange 5 when a locking member (not shown in Figures 9 to 12) is inserted between two adjacent panels in the manner previously described. Because the attachment flange 16 is divided into the segments each of the segments 16a'and 16b'can deform independently of the other so that the attachment rail can be gradually inserted between the adjacent attachment flanges by deforming first one segment 16b', then the next segment 16b'and so on until all of the segments 16b'and 16a' have been deformed about the rail flange 5 so as to engage with the inclined attachment surface 18 of the rail flange 5.

The cuts 125 may be formed by making cuts by a knife or blade or mechanical assembly in a formed panel after the panel has been moulded. However, in the preferred embodiment the cuts 125 are preferably formed during the moulding process of the panel my mould elements (not shown) which extend up into the mould cavity which will form the reinforcing flange 16 to thereby form the cuts 125 when the panel is moulded.

In the embodiment described with reference to Figures 1 to 8, the panel is provided with the inwardly facing surface 24 on the flange 16 and an outwardly facing surface 25 which define there between a recess 21. In the embodiment of Figure 10, the surface 25 is not provided which increases the open area of the screen region of the panel.

It will be apparent from the previous description that the surface 25 does not play any particular function in the

securement of the panels to the rail 3 because that securement occurs by engagement of the surface 24, after the flange 16 has been deformed, with the surface 18 of the rail flange 5. In the embodiment of Figure 10, the surface 24 still engages with the attachment surface 18 of the rail flange 5 thereby securing the panel to the rail and there is simply no outwardly facing surface 25 which rests on the inclined outer surface 5a of the rail 3.

In other embodiments (not shown), rather than provide discrete flat surface portions 122 on the rail 3, a continuous flat surface portion could extend along the length of the rail at a lower portion of the outer surface 15a of the rail. In still further embodiments the entire outer surface 15a of the rail could be formed as a generally vertical flat surface portion rather than an inclined surface portion as shown in the drawings.

Since modifications within the spirit and scope of the invention may readily be effected by persons skilled within the art, it is to be understood that this invention is not limited to the particular embodiment described by way of example hereinabove.