Cross-Reference to Related Applications

[0001] The present application claims priority from Australian Provisional Patent

Application No 2016905151 filed on 13 December 2016, the contents of which are incorporated herein by reference in their entirety.

Technical Field

[0002] This disclosure relates, generally, to screening of materials and, more particularly, to a screening panel and to a method of fabricating a screening panel. The disclosure extends further to a component for a screening panel.

Background

[0003] In material separation applications, screening panels are used over which the materials pass, the screening panels having apertures sized to pass material of a particular, selected size with the remaining, larger sized material passing over an upper surface of the screening panels for subsequent treatment.

[0004] One type of screening panel which is used makes use of shaped wire elements secured together to define the screening apertures. For example, the shaped wire elements may, generally, be in the form of a sinusoidal waveform with at least some of the "peaks" of adjacent wire elements being secured together to form the screening apertures. The fabricating steps required to manufacture such a screening panel are extremely cumbersome.

[0005] Typically, these fabricating steps include laying the wires on a flat surface and retaining the wires in their operative configuration while welding them together. The welded wires are then cast into a carcass mould to protect the apertures defined by the wires against ingress of material subsequently cast about a frame of the screening panel. The carcass mould is then placed on a screening panel frame within a casting mould and polyurethane is cast about the carcass mould and frame to form the screening panel. The carcass mould is then removed. It will be appreciated that the need for all the steps renders the fabricating process inefficient and costly. [0006] Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present disclosure as it existed before the priority date of each claim of this application.

Summary

[0007] In some embodiments of the disclosure, there is provided a screening panel which includes

a framework having a pair of opposed carrier members and a pair of opposed end members, each carrier member defining a receiving formation;

a plurality of discrete, shaped aperture defining elements carried by the framework, each aperture defining element having opposed end parts, aligned end parts at one end of each of the aperture defining elements being received in the receiving formation of one of the carrier members and aligned end parts at an opposed end of each of the aperture defining elements being received in the receiving formation of the other of the carrier members, the aperture defining elements being unsecured relative to one another in the framework; and a cover of a resiliency flexible material surrounding at least the carrier members and end members of the framework.

[0008] The aperture defining elements may be shaped so that, when they lie in planar, abutting relationship in the framework, with adjacent aperture defining elements being in mirror image relationship relative to each other, the aperture defining elements define screening apertures.

[0009] The aperture defining elements may be elongate metal elements, each of which is formed into a predetermined shape. For example, the aperture defining elements may be substantially sinusoidal in shape. The aperture defining elements may be formed by bending, crimping or stamping.

[0010] Each carrier member may be substantially rectangular, including square, in vertical cross-section having a pair of opposed sides, an operatively upper surface, an operatively lower surface and a pair of opposed ends with the receiving formation being defined in one of the sides proximate the operatively upper surface. The receiving formation of each carrier member may be in the form of a slot extending from the ends of the carrier member parallel to the upper and lower surfaces, the slot opening out into at least one of the ends of the carrier member.

[0011] The framework may comprise a framework cassette, the framework cassette being made up of one of the end members and the pair of spaced carrier members extending from the one of the end members, the framework further comprising the other end member which, prior to insertion of the aperture defining elements into the framework, is unsecured with respect to the framework cassette.

[0012] The framework may include an elongate stiffening member extending parallel to the carrier members between the end members, the stiffening member bearing against an operatively underside of each of the aperture defining elements. The stiffening member may serve therefore to inhibit flexing of a screening surface defined by the aperture defining elements. The stiffening member may be supported by cross members extending, at spaced intervals, between the stiffening member and the carrier members.

[0013] The stiffening member may carry a cap of a resiliency flexible material to facilitate positioning of the aperture defining elements in the framework. It will be appreciated that the cap of the stiffening member facilitates positioning of the aperture defining members in the framework while restraining them against free sliding movement, i.e. unassisted sliding movement, relative to each other while being positioned.

[0014] The cover may be a moulding formed around the carrier members and the end members of the framework. The moulding may define mounting formations along that part of the moulding covering the end members of the framework for mounting to a frame of screening equipment.

[0015] In some embodiments of the disclosure, there is provided a method of fabricating a screening panel, the method including

providing a framework cassette having a pair of spaced, parallel, elongate carrier members and a first end member to which a first end of each carrier member is attached, each of the carrier members defining a receiving formation in a part of the carrier member facing the other carrier member;

inserting a plurality of discrete, shaped aperture defining elements into the framework via the receiving formations of the carrier members so that the aperture defining members lie in abutting relationship, with adjacent aperture defining elements being in mirror image relationship relative to each other, to form a plurality of screening apertures and the aperture defining elements being unsecured relative to one another in the framework;

attaching a second end member to a second end of each of the carrier members to form a framework; and

forming a cover of a resiliently flexible material about the framework to complete the screening panel.

[0016] The framework may include a stiffening element running parallel to the carrier members and the method may include capping the stiffening element with a cap of a resiliently flexible material prior to inserting the aperture defining elements into the framework.

[0017] The method may include loading the completed framework into a mould and moulding the resiliently flexible material about each member of the framework to form the cover. By "completed framework" is meant the framework cassette into which the aperture defining elements have been inserted and the open end of which has been closed off by the second end member.

[0018] The method may include moulding the cover about each member of the framework individually. The method may further include forming mounting formations in each of those parts of the resiliently flexible material of the moulded cover covering the end members of the framework.

[0019] The disclosure extends further to a component for a screening panel, the component including a framework cassette having a pair of spaced, parallel, elongate carrier members and at least one end member to which a first end of each carrier member is attached, each of the carrier members defining a receiving formation in a part of the carrier member facing the other carrier member. [0020] The receiving formation of each carrier member may be a slot extending the length of the carrier member.

[0021] The component may include a second end member attachable to a second end of each carrier member.

[0022] The component may include a stiffening member running parallel to the carrier members. The stiffening member may be capped with a cap of a resiliently flexible material.

Brief Description of Drawings

[0023] An embodiment of the disclosure is now described by way of example with reference to the accompanying diagrammatic drawings in which:

[0024] Fig. 1 shows a perspective view, from below, of an embodiment of a screening panel; [0025] Fig. 2 shows a perspective view, from above, of the screening panel; [0026] Fig. 3 shows a plan view of the screening panel; [0027] Fig. 4 shows a side view of the screening panel; [0028] Fig. 5 shows an end view of the screening panel;

[0029] Fig. 6 shows a sectional end view of the screening panel taken along line VI- VI in Fig. 3 of the drawings;

[0030] Fig. 7 shows a sectional side view of the screening panel taken along line VII- VII in Fig. 3 of the drawings;

[0031] Fig. 8 shows a sectional side view, on an enlarged scale, of the part of Fig. 7 encircled by Circle Ά';

[0032] Fig. 9 shows a perspective view of a framework cassette which forms a part of a framework of the screening panel of Figs. 1-8; [0033] Fig. 10 shows a plan view of the framework cassette; [0034] Fig. 11 shows a side view of the framework cassette; [0035] Fig. 12 shows an end view of the framework cassette;

[0036] Fig. 13 shows a sectional side view of the framework cassette taken along line XIII- XIII in Fig. 10 of the drawings;

[0037] Fig. 14 shows, on an enlarged scale, a sectional end view of a part of the framework cassette taken along line XIV-XIV in Fig. 10 of the drawings;

[0038] Fig. 15 shows a plan view of a part of the screening panel after the framework cassette has been loaded with screening elements;

[0039] Fig. 16 shows a sectional end view of the part of the screening panel of Fig. 15 taken along line XVI- XVI in Fig. 15 of the drawings; and

[0040] Fig. 17 shows a side view of the part of the screening panel of Fig. 15. Detailed Description of Exemplary Embodiments

[0041] In the drawings, reference numeral 10 generally designates an embodiment of a screening panel. The screening panel 10 includes a framework 12. The framework 12 is shown in greater detail in Figs. 15-17 of the drawings and will be described in greater detail below with reference to those drawings. The screening panel 10 further defines a screening surface 14 constituted by a plurality of discrete, shaped aperture defining elements 16 (Fig. 3) carried by the framework 12.

[0042] A cover or moulding 18 of a resiliency flexible material covers the framework 12 of the screening panel 10. Typically, the moulding 18 is a mould of a synthetic plastics material having sufficient resilient flexibility to enable the moulding 18 to deform slightly when the screening panel 10 is inserted into screening equipment (not shown). Thus, for example, the moulding 18 may be of a synthetic plastics material such as a polyurethane having the required hardness. As an example, the polyurethane material used may have a Shore

Hardness of 93A.

[0043] Each aperture defining element 16 is a metal rod or wire which is bent or crimped into the required shape, typically, a sinusoidal shape. Each aperture defining element 16 may adopt other shapes, for example, sawtooth shapes, semicircular shapes, polygonal shapes, or the like. The aperture defining elements 16 are inserted into the framework 12 in mirror image -relationship to form screening apertures 20 (Fig. 3) in the screening surface 14 of the screening panel 10.

[0044] The framework 12 comprises two parts, a framework cassette 22, shown most clearly in Figs. 9-14 of the drawings and an end member, or plate, 24 (Figs. 15-17) to close off the framework cassette 22.

[0045] The framework cassette 22 comprises a pair of opposed elongate carrier members 26 extending parallel, and in spaced relationship, to each other, and extending orthogonally from a first end member, or plate, 28. As illustrated most clearly in Fig. 14 of the drawings, each carrier member 26 is substantially rectangular in vertical cross-section normal to a longitudinal axis of the carrier member 26. Each carrier member 26 has a pair of opposed sides 29 and 30, an operatively upper surface 32 and an operatively lower surface 34. A receiving formation, in the form of a slot 36, is defined in the surface 30 of each carrier member 26. The slot 36 extends the full length of each carrier member 26 proximate, and below, the upper surface 32 of the carrier member 26, the slot 36 opening out into an end 38 of the carrier member 26.

[0046] The surfaces 30 of the carrier members 26 face towards each other to facilitate sliding insertion of end parts of the aperture defining elements 16 into the slots 36 of carrier members 26 of the framework cassette 22. In other words, aligned end parts at one end of each of the aperture defining elements 16 are received in the slot 36 of one of the carrier members 26 with aligned end parts at an opposed end of each of the aperture defining elements 16 being received in the slot 36 of the other of the carrier members 36. Hence, unconnected, i.e. discrete, aperture defining elements 16 are individually slid into position in the framework cassette 22 to form the screening apertures 20. [0047] It will be appreciated that, in other embodiments (not shown), the receiving formation 36 of each carrier member 26 may adopt a different configuration, for example, a series of spaced apertures into each of which an end of an aperture defining element 16 is insertable. It will be appreciated that, in such an embodiment, the framework 12 may comprise both end plates 24 and 28 secured to the carrier members 26. The aperture defining elements 16 may be positioned in the framework 12 by being clipped into position rather than being slid into the slots 36 of the carrier members 26.

[0048] The framework cassette 22 includes a stiffening element, or stiffener, 40 extending from the end plate 28 parallel to the carrier members 26. The stiffener 40 is substantially centrally located between the carrier members 26 and is retained in position by cross-bracing 42 comprising a plurality of spaced cross members 44. Each cross member 44 extends parallel to the end plate 28 between the stiffener 38 and an associated carrier member 26.

[0049] As indicated above, the framework 12 includes the end plate 24 which closes off the open or free ends 38 of the carrier members 26 and which is also secured to the free end of the stiffener 40. The end plate 24 is secured to the carrier members 26 and the stiffener 40 after the aperture defining elements 16 have been inserted into the framework cassette 22 to form the completed frame 12 as shown in Figs. 15-17 of the drawings.

[0050] As shown most clearly in Figs. 6 and 16 of the drawings, the stiffener 40 is capped with a cap 46 of a resiliency flexible material. An operatively top region of the cap 46 bears against an underside of the aperture defining elements 16.

[0051] In use, to fabricate the screening panel 10, the framework cassette 22 is provided. A plurality of aperture defining elements 16 is provided to fill the opening of the framework 12. The number of aperture defining elements 16 to be provided will be dependent on the size of the apertures 20 to be formed. For a 4 mm aperture panel 10 with dimensions of

approximately 600 mm x 300 mm approximately 140 aperture defining elements 16 are provided.

[0052] As indicated above, each aperture defining element 16 is in the form of a wire or rod of a suitable metal such as stainless steel. Each aperture defining element 16 is pre-formed into its desired shape which, in the illustrated example, is substantially sinusoidal. The individual aperture defining elements 16 are inserted into the framework cassette 22 by inserting end parts of each element 16 into the slots 36 of the carrier members 26 of the framework cassette 22. As described above, alternating aperture defining element 16 are inserted in mirror image relationship to form the apertures 20 of the screening panel 10 when the aperture defining elements 16 are in abutment with one another.

[0053] The cap 46 of the stiffener 40 bears against each aperture defining element 16 to restrain the aperture defining elements 16 against excessive, free movement relative to the framework cassette 22 during the assembly process. The stiffener 40 also impart rigidity to the aperture defining elements 16 and restrains them against excessive flexing, in use.

[0054] Once the opening of the framework cassette 22 has been filled with the aperture defining elements 16, the end plate 24 of the framework 12 is secured in position to close off the open end of the framework cassette 22 and to retain the aperture defining elements 16 in position relative to the framework 12. The end plate 24 is secured to the ends 38 of the carrier members 26 and the free end of the stiffener 40 by being welded to the stiffener 40 and to the carrier members 26.

[0055] After the completed framework 12 has been formed, i.e. including the aperture defining elements 16, the completed framework 12 is placed in a mould (not shown) and the cover 18 is moulded around each of the carrier members 26 and the end plates 24 and 28. This may be done in a vertical mould to inhibit the mould material impinging on the aperture defining elements 16.

[0056] In the vertical mould, the cover 18 is moulded over each of the carrier members 26 and the end plates 24 and 28, individually. In other words, the first carrier member 26 is inserted into a mould cavity of the mould with the completed framework 12 arranged vertically and mould material is injected about the first carrier member 26. Once the mould material has cured or set, the completed framework is rotated through 90° and the first end plate 24 is arranged in the mould cavity into which mould material is injected about the first end plate 24. This process is repeated for the second carrier member 26 and the other end plate 28. [0057] In forming the cover 18, mounting formations 50 are formed in those parts of the moulded cover 18 covering the end plates 24 and 28 of the framework 12. The mounting formations 50 are in the form of clip-like components for clipping the screening panel 10 into a frame of screening equipment (not shown).

[0058] Hence, it is an advantage of the disclosed embodiments, that a screening panel 10 is provided, as well as a method of fabricating such a screening panel 10, which considerably simplifies the task of forming the screening panel 10. The need to weld or otherwise secure the aperture defining elements together is entirely eliminated as well as the need to protect the aperture defining elements while the framework components have material moulded about them. As a result, the time taken to form the screening panel 10 is substantially reduced in comparison with the manufacturing technique of which the Applicant is currently aware for manufacturing such screening panels. This, therefore, provides greater efficiencies and economic benefits in the fabrication of the screening panels 10.

[0059] It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the above-described embodiments, without departing from the broad general scope of the present disclosure. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.