Regulation 3.2 AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT (ORIGINAL) Name of Applicant: Illinois Tool Works Inc. Actual Inventor: Andrew Saul Barraclough Address for Service: DAVIES COLLISON CAVE, Patent Attorneys, 1 Nicholson Street, Melbourne, Victoria 3000. Invention Title: "Lifting anchors" Details of Associated Provisional Application No.: 2012901634 26 April 2012 The following statement is a full description of this invention, including the best method of performing it known to us: H:\plw\lnterwoven\NRPortbl\DCC\PLW\5279282_1.doc - 26/6/13 H~pin Jnternoen\NRPort\DCC\kPLWkU45142_1 doc-2AW2013 LIFTING ANCHORS The present invention relates to lifting anchors to be incorporated into concrete components during casting thereof to provide lifting points by which the component can be 5 lifted and more particularly to edge lift anchors for incorporation into concrete panels. One form of edge lift anchor for use with concrete panels comprises a head configured for engagement with a lifting clutch and opposed generally parallel legs extending from the head to provide anchorage within the panel, the legs being appropriately profiled along 10 their inner and outer edges for that purpose. Various different designs of this type of anchor are in widespread use. Edge lift anchors of this type are typically formed by cutting from thick metal plate using non-contact high energy cutting means such as a laser beam or plasma arc with the edges of the legs being profiled in this cutting process. 15 In existing lifting anchors of this type, the anchor is set within the concrete panel so that the plane of the anchor extends perpendicular to the opposed faces of the concrete panel whereby the outer profiled edge of each of its legs is inwardly of, and generally parallel to, a respective one of the two faces of the panel. When the panel is relatively thin, the outer edge of the anchor leg may be quite close to the face of the panel. 20 With an anchor of this type, due to the orientation of the profiling along the edges whereby the profiling faces towards the opposed faces of the panel, crack generation which may arise within the concrete when the anchor is under lifting load tends to occur in the thickness direction of the panel and thus towards the panel faces. As the concrete 25 thickness between the outer edge of the anchor leg and the adjacent face is unlikely to be substantial particularly in the case of relatively thin panels, the propensity for crack generation towards and into the adjacent face does impose restrictions on the lifting capacity of an anchor of a given size. Accordingly, to obtain an increase in lifting capacity additional measures have to be taken, for instance an increase in leg length and which in 30 turn results in increased material and manufacturing costs.
H:\ph\intenoven\NRPorbl\DCC\PLW\809971_ doC-22/07/2015 -2 According to the invention, there is provided a lifting anchor for embedment into a concrete panel, the anchor having a head of generally plate-like form for releasable engagement with lifting equipment, and at least one leg extending from the head and integrally formed with the head, the leg being profiled along its length so as to lock into 5 the surrounding concrete, wherein the profiling is along an edge of the leg extending generally parallel to the plane of the head whereby when the anchor is set within the panel with the head extending in the thickness direction of the panel substantially at right angles to the opposed faces of the panel, crack propagation generated in the concrete by the locking profiling when under lifting load will tend to be in the width direction of the panel, 10 the profiling being formed by a series of adjacent longitudinally-spaced formations along the length of the leg. An embodiment of the invention will now be described by way of example only with reference to the accompanying drawing, the sole figure of which is a perspective view of 15 an edge lift anchor in accordance with the preferred embodiment. The edge lift anchor shown in the accompanying drawings comprises a pair of opposed parallel legs 2 extending from a head 4 of plate-like form. The particular head shown is designed for use with a releasable lifting clutch in the form of a ring clutch having an 20 arcuate locking bolt received within an eye 6 in the head. Lifting clutches of that type are well known in the industry as are anchor heads of the general form as shown for use with such clutches. In the particular head shown, an aperture 8 is present beneath the eye 6 to receive a tension bar which permits an increase in the lifting capacity of the anchor. It is however to be understood that the aperture 8, while preferred, is not essential. 25 Each of the two legs 2 is profiled along opposed edges in order to lock into the surrounding concrete. However the profiling is not along the inner and outer edges of the legs but, rather, is along the edges at right angles to those edges. Accordingly, the profiling is along edges which may be considered as extending generally parallel to the plane of the plate 30 like head 4 rather than along inner and outer edges having a plane at generally right angles to the plane of the plate-like head as generally occurs with existing anchors of this type. Although the profiling may be of any suitable form so as to lock into the concrete such as a repeated undulating or sinuous profile, it is particularly preferred that the edges are formed H\plIneroven\NRPortbl\DCC\PLW\5045142I doc-26A)6/2011 -3 with a series of generally saw-toothed formations 8 along their length as described in Australian patent application 2006201337 of Cetram Pty Ltd (a subsidiary of the present applicants). Due to the nature of the saw-toothed formations as described in the aforesaid application, the interlock between the legs and the surrounding concrete tends to increase 5 as the lifting load increases. As a result of the orientation of the locking formations irrespective of whether they are undulating, saw-toothed (as is preferred) or of other form, they do not face in the thickness direction towards the faces of the panel, but instead face in the width direction towards the 10 edges of the panel whereby the direction of potential crack propagation is changed to the width direction and thus towards the edges of the panel. As there will inevitably be a substantial concrete thickness between the profiled edges of the legs and the edges of the panel, if crack generation does occur cracking will be confined within the body of concrete with the result that the lifting capacity does not need to be reduced to take account of such 15 cracking to the extent that is required when the profiling is along the inner and outer edges of the legs. Anchors in accordance with the preferred embodiment of the invention cannot, due to the orientation of the profiling, be cut from metal plate and instead other manufacturing 20 techniques are required, for example hot drop forging of a billet or casting. This does, moreover, lead to reduced manufacturing costs with reduced waste in comparison by cutting from thick metal plate. It also results in increased versatility in the shaping of the anchor as all faces of the anchor are able to be shaped according to requirements whereas when cutting from thick metal plate shaping can only be applied by appropriate shaping of 25 the cut. Although manufacturing techniques such as hot drop forging or casting are preferred, other suitable techniques which permit shaping of the anchor in 3-D, sintering or machining for example, can be used to permit versatility of design not achievable by the plate cutting process currently used. 30 The embodiment has been described by way of example only and modifications are possible within the scope of the invention. For example although it is preferred for the i:\plAnierwovn\NRPonbl\DCCPLVA5(45142_ I do-26A)6/2013 -4 anchor to have two parallel profile legs extending from the head, it is in principle feasible for the anchor to have only a single such leg profiled in the manner described.