Australian Patents Act 1990- Regulation 3.2A ORIGINAL COMPLETE SPECIFICATION INNOVATION PATENT Invention Title "Tactile ground surface indicator having a deformable retainer" The following statement is a full description of this invention, including the best method of performing it known to us: C \NRPortbl\DCC\AZM\4674193_1 DOC - 15110/12 C:\NRPonbl\DCCAZM\M694 _ I DOC.5/10f2012 Tactile Ground Surface Indicator Having a Deformable Retainer The content of the complete specifications of Australian patent application nos. 2008202373 and 2007101236 as originally filed is hereby incorporated 5 herein in its entirety by reference. The present invention relates to tactile indicators which provide a tactile and/or visual indication to a person, particularly a blind or vision-impaired person, walking on a ground surface. 10 Tactile ground surface indicators comprise specially configured protrusions which are positioned on walking surfaces. Such indicators are typically found in public areas in and around buildings and stairs, or at pedestrian crossings and the like, to forewarn pedestrians, particularly blind or vision-impaired persons, of an upcoming obstruction or hazard. A 15 person feeling tactile indicators under his or her feet, is made aware that his or her next step should be taken with caution. Tactile ground surface indicators can be located, for example, in approaches to steps or stairs, edges of railway platforms, traffic crossings, ramps and so forth. 20 It is advantageous to machine or mould tactile indicators from metal, particularly stainless steel. Stainless steel indicators are often adhered to the ground with adhesive such as epoxy adhesive, either directly on the ground surface or in a recess or cavity in the ground into which a stem of the indicator is received. The need for adhesive complicates the 25 installation of the tactile indicators, in that supplies of such adhesive must be maintained and the indicators are vulnerable to dislodgement before the adhesive has set, generally necessitating downtime, usually of the order of 24 hours, during which the area in which the indicators have been installed must be cordoned off. 30 According to the present invention, there is provided a tactile ground surface indicator, comprising: C:\NRPonbDCC\AZMwA49ss6- DOC-15/111/2012 -2 a metal body defining a portion of the indicator which is configured to overlie a ground surface, said portion being formed with a substantially flat bottom surface; and a retainer, configured for retaining engagement with the body, the retainer comprising an elongate retaining portion which is receivable into a cavity formed in the 5 ground and is configured with at least one protuberance which protrudes radially outwardly so as to deform against a wall of the cavity during installation of the indicator such that said flat bottom surface is retained in abutment with the ground surface to support said portion of the indicator on the surface. 10 Preferably, said at least one protuberance comprises ribs which are spaced apart around the retaining portion, each rib extending axially along the retaining portion. In a preferred embodiment of the present invention, the body includes a downwardly projecting member, preferably a stem but possibly a flange, and the retainer comprises a 15 deformable casing applied to the downwardly projecting member either prior to or as a result of said installation. In one embodiment of the invention, the retainer and body are provided as a unitary assembly, whereby driving the indicator, and in particular the retaining portion, into the 20 cavity causes the deformation of the retaining portion. Preferably, the retaining portion is permanently fixed to the body in the unitary assembly. Preferably, the retaining portion is moulded to the body - preferably to the projecting member thereof. The projecting member retaining portion, which preferably comprises a casing, applied thereto may be driven into the cavity to cause deformation of the casing. 25 In another embodiment of the invention, the retainer and body are provided separately and configured to interengage upon installation, whereby to be retainedly coupled. In a preferred embodiment of the present invention, the body includes a downwardly projecting member, preferably a stem, and the retainer comprises a deformable casing comprising an 30 upwardly opening recess arranged for downward receipt of the downwardly projecting member therein. Preferably, the downwardly projecting member is sized such that it urges C.WRPortbI\DCC\AZM\466)46_1 DOC-I5/10/201 l -3 the retaining portion radially outwardly when inserted into the recess, whereby the retaining portion may be first inserted into the cavity alone, with little or no force, and the downwardly projecting member driven into the recess to force the retaining portion against the cavity wall to effect the deformation. 5 Preferably, said portion defined by the body is substantially solid. In one preferred embodiment of the invention, the portion defined by the body defines the entirety of a head of the indicator. In another preferred embodiment of the invention, an upper part of said portion defined by the body is configured with an upwardly opening void and the indicator 10 includes an anti-slip portion, formed separately from said portion defined by the body, arranged to occupy the void such that a head of the indicator is defined by said portion defined by the body and the anti-slip portion. Said portion may comprise, for example, an infill, e.g. a carborundum infill. Preferably the anti-slip portion is arranged in the void prior to installation of the indicator. 15 Deformation of the protuberance(s) against the wall establishes sufficiently tight contact engagement between the retaining portion and the wall to resist upward pulling forces on the indicator. Such engagement will generally include frictional engagement. 20 Advantageously, the tactile ground surface indicator can thus be installed very rapidly, without any adhesive, whilst still being robust and durable. In one embodiment, the at least one protuberance comprises a pair of opposed ribs which extend in general alignment with the direction of insertion of the retaining portion in the 25 recess to engage opposed portions of the cavity wall. In an alternative preferred embodiment of the present invention, the at least one protuberance extends circumferentially around the retaining portion to engage the opposed portions. In particular, the at least one protuberance may comprise one or more ribs extending around the retaining portion. The ribs may define a barbed or saw-tooth configuration which 30 facilitates insertion of the retaining portion.
C \NRPorbl\DCCAZM466946_ I DOC-15/10/21)12 -4 The casing may be overmoulded to, or moulded over, the projecting member. In a preferred embodiment of the present invention, the retaining portion is plastically deformable against the cavity wall. 5 In one embodiment of the present invention, the at least one protuberance comprises opposed ribs which extend in general alignment with the direction of insertion of the retaining portion in the cavity to engage opposed portions of the cavity wall. 10 In an alternative preferred embodiment of the present invention, the at least one protuberance extends circumferentially around the retaining portion to engage the opposed portions. In particular, the at least one protuberance may comprise one or more ribs extending around the retaining portion. The ribs may define a barbed or saw-tooth configuration which facilitates insertion of the casing. 15 Preferably, the metal comprises steel. Preferably, the steel is stainless steel. Preferably, the retaining portion is closed at a lower end thereof. 20 In the preferred embodiments of the present invention, the retaining portion and projecting member are interlocked prior to or as a result of installation. Said portion defined by the body and the projecting member may be integrally formed. 25 Preferably, said portion defined by the body is configured with a flat base defining said flat surface. Preferably, the indicator comprises a head which is generally circular or button-shaped and comprises a bottom, an upper portion and a surrounding sloped side wall extending 30 upwardly and radially inwardly from the bottom to the upper portion. The generally circular or button-shaped head may further comprise an upwardly projecting lip extending C:\NRPonbrDCC\AZM\46694X6.1 DOC-I S020 12 -5 around the periphery of the upper portion to be engageable with the sole of a person's shoe. The lip defines a protuberance which can catch and engage the sole of the person's shoe, particularly as moved against the tactile ground surface indicator in a direction having a sideways component, thereby preventing slipping, especially in the general plane defined 5 by the side wall, and conferring improved anti-slip characteristics to the tactile ground surface indicator. The inclined side face may be substantially smooth, affording the indicator enhanced visual characteristics, aesthetic appeal and/or simplified manufacture, whilst the upwardly projecting lip, if present, serves to prevent a person slipping, the risk of which may otherwise be particularly high as a result of the side wall being smooth. In a 10 preferred embodiment of the present invention, the lip projects from a top end of the side wall. In a particular embodiment of the present invention, the side wall is frustoconical. Preferably, the upper portion is provided with anti-slip formations arranged radially inward of the lip. Preferably, the formations comprise upwardly projecting ribs arranged at successive radial positions between the lip and a centre of the upper portion. In a preferred 15 embodiment of the present invention, the ribs are continuous. In an alternative embodiment, the ribs may be discontinuous. In a preferred embodiment of the present invention, the ribs are concentric. In an alternative embodiment, the ribs may be arranged end-to-end so as to define a continuous spiral. In a preferred embodiment of the invention, an upper end of the lip and upper ends of the ribs are coplanar. 20 Consistent with national standard no. AS/NZS 1428, tactile ground surface indicators according to preferred embodiments of the present invention provide areas of raised ground surface texture treatment, designed to provide blind or vision-impaired pedestrians with warning and/or directional orientation information. 25 The present invention will now be described, by way of non-limiting example only, with reference to the drawings, in which: Figure IA is a perspective view of a tactile ground surface indicator according to a first embodiment of the invention; 30 Figure l B is a top view of the indicator shown in Figure IA; Figure IC is a cross-sectional elevation view taken through section J-J in C:\NRPortbl\DCC\AZM\466"46_t DOC-15/10/202 -6 Figure 1 B, showing deformable longitudinal ribs of a casing of the indicator; Figure ID is a cross-sectional elevation view taken through section K-K in Figure IB, showing channels of the casing of the indicator; Figure IE is a further perspective view of the indicator shown in Figure IA; 5 Figure IF is a bottom view of the indicator shown in Figure IA; Figure 2A is a perspective view of the body of the tactile ground surface indicator according to both the first embodiment and a second embodiment of the invention; Figure 2B is a top view of the body; Figure 2C is a cross-sectional elevation view taken through section D-D in 10 Figure 2B; Figure 2D is a rotated side view of the body; Figure 2E is a further perspective view of the body; Figure 2F is a bottom view of the body; Figure 3A is a perspective view of a tactile ground surface indicator according to 15 the second embodiment of the invention; Figure 3B is a top view of the indicator showing Figure 3A; Figure 3C is a cross-sectional elevation view taken through section F-F in Figure 3A; Figure 3D is a further perspective view of the indicator shown in Figure 3A; 20 Figure 3E is a bottom view of the indicator shown in Figure 3A; Figure 4A is an elevation view of a tactile ground surface indicator according to a third embodiment of the invention; Figure 4B is a cross-sectional elevation view, taken through section D-D in Figure 4A, of the tactile ground surface indicator shown in Figure 4A; 25 Figure 4C is a perspective elevation view of the retaining portion shown in Figures 4A and 413; Figure 5A is a perspective view of an indicator portion defining a head of each of the indicators according to the first, second and third embodiments; Figure 5B is a top view of the indicator portion shown in Figure 5A; 30 Figure 5C is a cross-sectional elevation view taken through section D-D in Figure 5B; C\NRPonbDlCC\A2M\46694X6_I DOC-15/10/2012 -7 Figure 5D is a view of detail E as shown in Figure 5C; Figure 5E is a rotated side view of the indicator portion shown in Figures 5A to 5D; Figure 5F is a further perspective view of the indicator portion; Figure 6A is an upper perspective view of an indicator according to a fourth 5 embodiment of the invention, from one side; Figure 6B is a lower perspective view of the indicator shown in Figure 6A, from the other side; and Figure 7 is a perspective view of an indicator according to a fifth embodiment of the invention. 10 A tactile ground surface indicator 1 according to a first embodiment of the invention, as depicted in Figure lA to IF, comprises a body 3 which is moulded as a single piece from stainless steel, or machined from a solid bar of stainless steel, and, as can best be seen in Figures IC and ID and Figures 2A to 2F, comprises an indicator head 5 which will be 15 positioned above a ground surface, and a downwardly projecting member in the form of a stem 7 which is receivable in a cavity, provided in the ground, which locates the indicator 1 in position. The indicator 1 further comprises a retainer 9, in the form of a generally elongate casing, 20 which is received over, and engaged with, the stem 7, the casing, which is for holding the indicator 1 in the ground, being made from suitably deformable plastic, whereby it can deform against an annular wall of the cavity when the indicator 1 is driven into the cavity. The casing in this embodiment is moulded as a single piece of plastically deformable 25 plastic, and is moulded to the stem 7. The casing 9 is configured as a cap which covers the stem 7, the cap defining a recess II which is occupied by the stem 7. The casing 9 has a generally circular outer transverse cross-sectional profile. The exterior of the casing 9 includes a pair of opposed ridges or ribs 13 which extend 30 linearly and longitudinally along the casing 9 from a top end of the casing 9. The ribs 13 are provided at diametrically opposite positions on the casing 9. The ribs 13 protrude C NRPobl\DCC\AZM46946_I DOC-15/10/2U12 -8 radially outwardly to be engageable with the annular wall of the cavity so as to deform against the wall when the indicator I is driven into the cavity, thus permanently locking the casing in the cavity and anchoring the indicator I to the ground. To this end, the outermost extents of the ribs 13 are spaced apart by a distance which slightly exceeds the diameter of 5 the cavity. The lower end 15 of the casing 9 is tapered radially inwardly to facilitate driving of the encased stem 7 into the ground. 10 The casing 9 further comprises a pair of longitudinally extending channels 17 which are disposed at diametrically opposite positions on the exterior of the casing 9 and extend generally linearly between the top and bottom ends of the casing 9. The channels 17 define spaces into each some of the material of the casing 9 may be displaceable when the casing 9 is driven into the cavity, under a radially inward pressure exerted by the cavity 15 wall, giving rise to a radially outward biasing of the casing against the cavity wall, which assists retention of the indicator 1 to the ground. Referring also to Figures 2A to 2F, the stem 7 is configured with an annular channel 19 which defines a space into which a complementarily configured, radially inwardly 20 projecting portion 21 of the casing 9, in the form of an annular rib in the recess 11, is received. The channel 19 defines an upper shoulder 23, providing a downwardly facing surface 25, and a lower shoulder 27, providing an upwardly facing surface 29. Similarly, the projecting portion 21 defines an upper shoulder 30, providing a downwardly facing surface 31, and a lower shoulder 33, providing an upwardly facing surface 35. The 25 downwardly facing surface on the casing 9 abuts the upwardly facing surface on the stem 7 to restrain the body 3 from upward movement relative to the casing 9. Similarly, abutment of the downwardly facing surface of the stem 7 with the upwardly facing surface of the casing 9 prevents downward movement of the body 3 with respect to the casing, as does abutment of the upper end of the casing 9 with the underside of the indicator head 5. 30 Relative movement between the casing 9 and body 3 is thus prevented. The stem 7 and casing 9 are thus rigidly interlocked.
C \NRPortbIWCC\AZM\4664K6_ I DOC-15/11W2012 -9 As will be clear from Figures lB and ID, the channels 17 lie in an upright plane which is perpendicular to an upright plane in which the ribs 13 lie. The ribs 13 are thus provided intermediate the channels 17 around the exterior of the casing 9. 5 In the following description of the second embodiment, the same reference numerals as used in respect of the first embodiment will be used to designate common features. The indicator 1' according to the second embodiment is shown in Figures 3A to 3E. It is 10 identical to the indicator I of first embodiment in every respect except that the casing comprises opposed ridges or ribs 13' which, instead of extending longitudinally along the casing 9', extend around the casing 9'. The ribs 13' each extend between the channels 17 and are provided at opposite sides of a longitudinally extending plane passing through the channels, the ribs 13' thus defining a substantially annular deformable portion. The ribs 13' 15 are provided approximately halfway down the casing. In an alternative embodiment, the casing comprises more than two ribs, constituting protuberances or protruding portions, extending therearound to define a substantially annular deformable portion. In another alternative embodiment, the deformable portion is 20 defined by deformable wings protruding from the casing. A tactile ground surface indicator 1" according to a third embodiment of the invention, as depicted in Figures 4A to 4C, also comprises a body portion 3 (see Figure 4B) moulded as a single piece of stainless steel, or machined from a solid bar of stainless steel. The body 25 portion 3 comprises a head 5, which is identical to the heads of the first and second embodiments. The body portion 3 further comprises a stem 7 and an elongate retainer 9" into which the stem 7 is lockingly receivable. In this embodiment, the retainer 9", instead of being overmoulded to the stem 7, is formed 30 separate from the body 3 and is constructed to receive lockingly the stem 7 during installation in the ground, as will be described in greater detail below.
C.\NRPonbl\DCCAZN A94X6_I1 DOC-15/10/2012 - 10 The retainer 9", a perspective view of which is shown in Figure 4B, is moulded as a single piece of plastically deformable plastic. The retaining portion 9" takes the form of a generally cylindrical cap which is receivable over the stem 7, the cap having a recess I I 5 which is to be occupied by the stem 7. The retainer 9" comprises an elongate retaining portion which is configured with a plurality of radially outwardly projecting protuberances or protruding portions, in the form of ribs or ridges 13" which are arranged axially or longitudinally along the retaining 10 portion 9" and which each extend therearound. The ridges 13" provide a serrated longitudinal cross-sectional profile, affording the exterior of the retaining portion 9" a barbed configuration. As can be seen in Figure 4A, each ridge 13" extends upwardly and radially outwardly to define an annular edge 71. The retaining portion further comprises openings in the form of a pair of axially extending slots 73 disposed on opposite sides of 15 the retaining portion, the slots 73 providing communication between the outside of the retaining portion and the recess 11. The slots 73 are located at approximately the same axial position along the retainer 9" as the ridges 13". The stem 7 has a lower portion 7A, an upper portion 7B and a tapered step 7C between the 20 upper and lower portions. The diameter of the lower portion 7A is less than that of the recess, whereas the diameter of the upper portion 7B is slightly greater than that of the recess. The inner wall of the recess 7 is further provided with a plurality of circumferential 25 grooves 75 which lockingly receive circumferential ribs 77 formed on the stem 7, as will be described in further detail below. Installation of the tactile ground surface indicator 1" according to the third embodiment commences with drilling a cavity into the ground, the cavity having approximately the 30 same diameter and depth as the retaining portion. The retaining portion 9" is then inserted into the cavity. Each edge 71, because the ribs extend upwardly and radially outwardly, is C \NRPonbrDCC\AZM ,694x6 I.DOC-15/10/212 a trailing edge when the retaining portion is inserted, whereby any engagement between it and the cavity wall during insertion will not hinder insertion. Next, the lower end of the stem 7 of the body portion 3, which is tapered to facilitate 5 insertion, is introduced into the open upper end of the retaining portion 9" and forced down through the recess 7, whereby the tapered step 7C and upper portion 7B engage the inner wall of the recess 7 to cause the walls of the retaining portion, including the ridges 13", to be displaced radially outwardly such that the tips 71 are forced against the annular wall of the cavity, whereupon the ridges 13" serve as barbs which engage with the annular wall 10 and will resist pulling forces which may otherwise be sufficient to remove the indicator 1" from the ground, thus locking the retaining portion in the cavity. Because the ridges 13" are plastic, they will deform slightly when forced against the annular wall. The radially outward displacement of the ridges 13" is enabled, or at least facilitated, by the slots 73. 15 Upon insertion of the stem 7 into the recess 11, the ribs 75 are received in the grooves 77. As can be seen from Figure 4A, the ribs 77 and grooves 75 are complementarily profiled such that the body portion 3 and the retainer 9" are locked together, the stem thus anchoring the indicator 1" in the cavity. Since the retainer 9" is made out of plastic, the retaining portion is resiliently flexible to a sufficient extent to enable the inner wall of the 20 recess 11 to be displaced radially outwardly to allow passage of the ribs 73 past the grooves 75 during insertion of the stem 7, until the stem 7 has been fully inserted, whereupon the grooves 75 align with the appropriate respective ribs 73 and the inner wall contracts slightly so that the ribs 73 are received in the grooves 75. 25 Because the casing 9/9' in each of the first and second embodiments is permanently fixed to the stem 7, each indicator 1/1' is, advantageously, provided as a single or unitary item, whereby it is very quick and easy to install. The head 5 of indicators 1, 1' 1" is illustrated in Figures 5A to 5F. The head 5, which is 30 provided as a single piece, has a generally circular transverse cross section and includes a bottom portion 56, defining, at the bottom of the head 5, a peripheral shoulder 55 and a C:WRPorbl\DCC\AZM\4669486_L DOC-15/10/2012 - 12 downwardly facing surface 58 arranged to abut the ground surface. The head 5 further includes an upper portion 57 and a sloped or tapered smooth side wall 59, extending upwardly and radially inwardly from the bottom portion 56 to the upper portion 57 and being inclined at an angle of approximately 350 to 450 from the downwardly facing 5 surface 58. The diameter of the bottom portion is 35 millimetres. The upper portion 57 is defined by an upwardly facing surface 61, which is bounded by an upper end of the side wall and which in each described embodiment is level with the upper end of the side wall. The diameter of the upwardly facing surface 61, and thus the upper 10 portion, is 25 millimetres. The distance between the downwardly facing surface 58 and the upper portion 57 is 4 to 5 millimetres. A circular lip 60 is provided at a radially outermost position on the upper surface 61 and extends upwardly from the upper surface 61 to protrude outside of the curved surface of an 15 imaginary cone a section of which is formed by the side wall 59. The upper end 64 of the lip 60 lies outside of the imaginary cone. The lip 60 has a height of 0.5 millimetres. The lip 60 is able to catch and engage the sole of the person's shoe, particularly as moved against the tactile ground surface indicator in a direction having a sideways component, 20 thereby preventing slipping, especially in the general plane defined by the side wall, and conferring improved anti-slip characteristics to the tactile ground surface indicator. Advantageously, the lip 60 confers upon the indicator 1 an R13 anti-slip rating in accordance with Australian Standard AS 4586:2004. 25 To enhance gripping further, a gripping pattern 63 is provided on the upper surface 61, the gripping pattern 63 comprising a plurality of ribs in the form of concentric rings 65 extending upwardly from the upper surface 61. The upper ends or tips of the rings, which define the uppermost extent of the gripping pattern 63, lie in a plane which is 30 0.5 millimetres above the upper portion 57 or the plane defined by the upwardly facing surface 61 and are coplanar with the top end of the circular lip 60 and the upper end 64.
C RPonbl\DCC\AZM\46694I6_L DOC.15/10/21)12 - 13 The concentric rings 65 each have a thickness of 0.4 millimetres, as does the lip 60. The concentric rings 65 have a radial pitch P of 1.1 millimetres, each ring 65 thus having a thickness which is approximately 35% of the radial pitch P. Annular spaces 66 are defined 5 between the rings 65, the annular spaces having a radial dimension of 0.7 millimetres, as does the annular space defined between the lip 60 and the outermost ring 65. A disc-shaped portion 67 is located on the centre of the upwardly facing surface 61 and extends upwardly therefrom to end flush with the upper ends of the rings 65. The 10 disc-shaped portion 67 has a diameter of 3mm. Manufacture of the indicator 1 and 1' according to the first and second embodiments firstly comprises moulding of the body 3, including the head 5, from stainless steel, or machining it from a solid billet of stainless steel. 15 With the body 3 arranged upside down, the stem 7 is then centrally positioned in a mould which defines the external configuration of the casing 9/9', the flat underside of the head 5 abutting a lower end of the mould to close that lower end. Molten plastic is then injected into the space between the mould and the stem, through a suitable opening provided in the 20 mould. The plastic is then allowed to cool and set, whereupon the finished indicator 1/1' is removed from the mould. An indicator 101 according to a fourth embodiment of the present invention is shown in Figures 6A and 6B. The indicator 101 includes the same body 3 as in the indicators I 25 and 1' and a casing 109 which is applied to the body 3 in exactly the same manner as the casings 9 and 9' are applied to body 3 in the indicators 1 and ' respectively, though is configured with to pairs of opposed ribs 13A and 13B which extend linearly and longitudinally along the casing 9 from a top end of the casing 9, the ribs of each pair lying at diametrically opposite positions on the casing to define planes which are perpendicular 30 to each other. The ribs 13A and 13B protrude radially outwardly to be engageable with the annular wall of the cavity so as to deform against the wall when the indicator I is driven C.NRPorblDCC\AZM\46.94.(6I DOC.15/l/20'12 - 14 into the cavity, thus permanently locking the casing in the cavity and anchoring the indicator 1 to the ground. To this end, the outermost extents of the ribs 13A are spaced apart by a distance which slightly exceeds the diameter of the cavity and the outermost extents of the ribs 13B are likewise spaced apart. 5 An indicator 201 according to a fifth embodiment of the present invention is shown in Figure 7. The indicator 201 is identical to the indicator 101 though the casing 209 thereof is configured at its upper end with a section having a diameter which is less than the spacing between the outermost extents of the ribs 13A and the spacing between the 10 outermost extents of the ribs 13B, that section defining a neck 250, at the lower end of which the ribs 13A and 13B terminate. The neck 250 defines a relief which may facilitate deformation of the casing 209 in the cavity. Because in the indicator according to each of the first, second, fourth and fifth 15 embodiments, the casing is fixed to the respective stem, each of those indicators is, advantageously, installed as a single or unitary item, and thus very quickly and easily. It will be apparent to a person skilled in the relevant art that various changes in form and detail can be made therein without departing from the spirit and scope of the invention. 20 Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" and "comprising", will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps. 25 The reference in this specification to any prior publication (or information derived from it), or to any matter which is known, is not, and should not be taken as an acknowledgment or admission or any form of suggestion that that prior publication (or information derived from it) or known matter forms part of the common general knowledge in the field of 30 endeavour to which this specification relates.