Abstract:
This invention relates to an anchoring device for use in retaining a railway rail fastening clip, the device comprising a stem for embedding in a rail support member, a head extending from the stem and comprising a generally hook-shaped portion for extending over a portion of the clip to effect retention and terminating at an end apart from the stem, and wherein in use, said end terminates at a sealing plate for bridging the end of the hook-shaped portion and the stem. An associated anchoring device assembly and railway rail fastening assembly are also disclosed.

Description:
PRIORITY DOCUMENT 
       [0001]    The present application claims priority from: 
         [0002]    Australian Provisional Patent Application No 2012903815 titled “ANCHORING DEVICES FOR RAIL FASTENING CLIPS” and filed on 31 Aug. 2012. The content of this application is hereby incorporated by reference in its entirety. 
       TECHNICAL FIELD 
       [0003]    The present invention relates to railway system construction. More particularly, the present invention relates to anchoring devices for rail fastening clips. 
       BACKGROUND 
       [0004]    In railway system construction it is common practice for each rail to be secured to a support member or sleeper using a support plate which is located between a foot of the rail and a supporting surface of the sleeper. Such a support plate may include, for example, a “tie plate” or a “turnout plate”. There is also an anchoring device anchored to the sleeper on each side of the rail (hence they are called shoulders) retaining a fastening clip which bears against the foot of the rail. 
         [0005]    Anchoring devices suitable for use in anchoring a railway rail-fastening clip to a rail foundation are commonly known as shoulders. 
         [0006]    Whilst other techniques are used, it is known to manufacture these anchoring devices or shoulders via sand casting of molten metal. 
         [0007]    Cast metal parts are generally heavy, and if voids are required to retain the rail-fastening clip, and they generally are, then separate cores will be required to form these, adding to the complexity and expense of the casting process. 
         [0008]    It is against this background and the problems and difficulties associated therewith that the present invention has been developed. 
         [0009]    Certain objects and advantages of the present invention will become apparent from the following description, taken in connection with the accompanying drawings, wherein, by way of illustration and example, an embodiment of the present invention is disclosed. 
       SUMMARY 
       [0010]    According to a first aspect, there is provided an anchoring device for use in retaining a railway rail fastening clip, the device comprising a stem for embedding in a rail support member, a head extending from the stem and comprising portion for extending over a portion of the clip to effect retention and terminating at an end apart from the stem, and wherein in use, said end terminates at a sealing plate for bridging the end of the hook-shaped portion and the stem. 
         [0011]    In one form, the portion for extending over a portion of the clip to effect retention is generally hook shaped. 
         [0012]    In one form, the hook-shaped portion comprises a means for engaging the sealing plate at or near the end thereof. 
         [0013]    In one form, the stem comprises a means for engaging the sealing plate. 
         [0014]    In one form, the clip is approximately ‘e’ shaped. 
         [0015]    In one form, the head defines a recess for receiving a portion of the clip. 
         [0016]    In one form, the recess is a slot. 
         [0017]    In one form, the slot shaped recess extends into the head at an angle relative to the longitudinal axis of the stem, and which is inclined towards a corner defined between the head and the stem. 
         [0018]    In one form, the stem is approximately Y-shaped, and comprises portions forming upper ends of the Y for connecting the stem to the head of the device. Of course the stem need not by Y-shaped, instead it may be of substantially constant cross section throughout its length, and/or solid throughout its length. 
         [0019]    In one form, the anchoring device is formed by a casting process. 
         [0020]    In one form, the anchoring device is shaped for casting without a core. 
         [0021]    In one form, the recess for receiving a portion of the clip is shaped for casting without a core. 
         [0022]    In one form, the end of the hook shaped portion is unsecured, and in alternative the end of the hook shaped portion is secured to or with respect to the rail support member. 
         [0023]    In a further aspect the invention may be said to reside in a cast anchoring device for use in retaining a railway rail fastening clip, the device comprising a stem for embedding in a rail support member, a head extending from the stem and comprising a generally hook-shaped portion for extending over a portion of the clip to effect retention and terminating at an end apart from the stem. 
         [0024]    For the purpose of this specification the tern ‘cast’ means to make by casting, which is a process whereby a liquid material, such as molten metal or similar, is shaped in a mold. 
         [0025]    In a further aspect the invention may be said to reside in an anchoring device for use in retaining a railway rail fastening clip, the device comprising a stem for embedding in a face of a rail support member, a head extending from the stem and comprising a generally hook-shaped portion for extending over a portion of the clip to effect retention and terminating at an end apart from the stem, and wherein in use, said end terminates at or near the face of the rail support member. 
         [0026]    By saying that the end of the generally hook-shaped portion terminates ‘at or near the face of the rail support member’, it is meant that in the case that the end penetrates the support member, it does not do so to any great extent or depth, only slightly, or to a small degree. 
         [0027]    In one form, the end of the generally hook-shaped portion does not penetrate the support member. 
         [0028]    In a further aspect the invention may be said to reside in a railway rail fastening assembly comprising a resilient railway rail fastening clip and an anchoring device as described above, wherein the head is generally hook shaped, and extends over a portion of the clip to effect retention of the rail to the sleeper. 
         [0029]    In a further aspect the invention may be said to reside in a cast anchoring device for use in retaining a railway rail fastening clip, the device comprising a stem for embedding in a rail support member, and a head extending from the stem shaped both for retaining the clip and casting thereof without a core. 
         [0030]    A detailed description of one or more embodiments of the invention is provided below along with accompanying figures that illustrate by way of example the principles of the invention. While the invention is described in connection with such embodiments, it should be understood that the invention is not limited to any embodiment. On the contrary, the scope of the invention is limited only by the appended claims and the invention encompasses numerous alternatives, modifications and equivalents. For the purpose of example, numerous specific details are set forth in the following description in order to provide a thorough understanding of the present invention. 
         [0031]    The present invention may be practiced according to the claims without some or all of these specific details. For the purpose of clarity, technical material that is known in the technical fields related to the invention has not been described in detail so that the present invention is not unnecessarily obscured. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0032]    Embodiments of the present invention will be discussed with reference to the accompanying drawings wherein: 
           [0033]      FIG. 1  is an upper isometric view of an anchoring device; 
           [0034]      FIG. 2  is a lower isometric view of the anchoring device of  FIG. 1 ; 
           [0035]      FIG. 3  is a front view of the anchoring device; 
           [0036]      FIG. 4  is a top view of the anchoring device; 
           [0037]      FIG. 5  is a bottom view of the anchoring device; 
           [0038]      FIGS. 6 and 7  are opposing side views of the anchoring device; 
           [0039]      FIG. 8  is a rear view of the anchoring device; 
           [0040]      FIG. 9  is a top isometric view of a railway rail fastening assembly comprising the anchoring device of  FIGS. 1 through 8 ; 
           [0041]      FIG. 10  is a cross-sectional view through the railway rail fastening assembly of  FIG. 9 ; 
           [0042]      FIG. 11  is an upper isometric view of an anchoring device assembly comprising the anchoring device of  FIG. 1 , and a sealing plate; and 
           [0043]      FIG. 12  is a lower isometric view of the anchoring device assembly of  FIG. 11 . 
       
    
    
       [0044]    In the following description, like reference characters designate like or corresponding parts throughout the figures. 
       DESCRIPTION OF EMBODIMENTS 
       [0045]    Referring now to  FIGS. 1 through 8 , where there is illustrated an embodiment of an anchoring device  1  of the type commonly known as ‘a shoulder’ (so these terms are hereinafter used interchangeably) and suitable for use in anchoring a railway rail-fastening clip to a rail foundation. 
         [0046]    The anchoring device  1  comprises a stem  1 B and a generally hook shaped head  1 A. The stem  1 B is, in this embodiment, substantially Y-shaped: it is connected to the head  1 A by upper portions  12  of the Y, and it comprises a barb  14  at a point toward a terminal end thereof. 
         [0047]    The anchoring device  1  illustrated in  FIGS. 1 through 8  is manufactured using a sand casting process, resulting in an anchoring device  1  which is formed from a single, integral piece of cast iron. However, it is also possible that the anchoring device  1  could be manufactured from other materials (or indeed formed by another method), such as composites, or other metals, or indeed any other material sufficient to withstand the load exerted thereon by carriage of a train. Moreover, conceivably though less desirably, anchoring device  1  could be assembled from separate pieces of material. 
         [0048]    Referring now to  FIGS. 9 and 10 , where there is illustrated a railway rail fastening assembly  100  comprising a rail  102  to be secured to a support member or sleeper  104  (so these terms are hereinafter used interchangeably) using a support plate  106  which is located between a foot  102 A of the rail  102  and a supporting surface of the sleeper  104 . Such a support plate  106  may include, for example, a “tie plate” or a “turnout plate”. There is an anchoring device  1  anchored to the sleeper  104  on each side of the rail  102  (hence they are called shoulders) retaining a generally ‘e’ shaped fastening clip  108  which bears against the foot of the rail  102 . 
         [0049]    The generally hook shaped head  1 A of the shoulder  1  extends over and around a portion of the clip  108  by defining in the underside thereof a slot-shaped recess  2  with a downwardly directed opening for receiving and capturing the portion of the clip  108 . 
         [0050]    Typically, these anchoring devices or shoulders  1  are secured to a concrete railway sleeper  104  by embedding the stem  1 B of the shoulder  1  in the concrete during manufacture of the sleeper  104 . Once embedded, the barb  14  resists withdrawal of the stem  10  from the concrete. 
         [0051]    The concrete sleepers  104  are manufactured upside down, so that the top of the finished sleeper  104  is formed by a floor of a mould. During manufacture, the parts of the shoulder  1  that stick up above the finished sleeper, namely the head  1 A, protrude down through apertures cut into the floor of the mould at appropriate positions for this purpose. The stems  1 B of the shoulders  1  that end up cast into the concrete sleeper  104  stick up into the mould before the concrete is poured. When the concrete has been poured and allowed to set, the sleepers  104  are lifted out of the moulds and turned the right way up. 
         [0052]    A difficulty with this process is that if the apertures in the bottom of the mould pockets are not a close fit around the stems  1 B of the shoulders  1 , then concrete will leak through the gap and it may then set on to parts of the shoulder  1  above the finished concrete level (ie the head  1 A) and prevent the clip  108  from engaging properly. Alternatively, this unwanted concrete must be removed via a time consuming and therefor costly cleaning operation before the clip  108  will fit properly. 
         [0053]    A solution to this problem involves placing a sealing plate  120  (see  FIGS. 8 and 9 ) around the stem  1 B near the underside of the head  1 A of the anchoring device  1 , and over the aperture in the floor of the mould before the concrete is introduced into the mould. It his way the sealing plate  120  seals the aperture in the mould and prevents the ingress of concrete into the head  1 A of the shoulder  1 . 
         [0054]    Post forming, the sealing plate  120  is molded (embedded) into the top of the concrete sleeper  104  (see  FIG. 9 ), such that its top face is flush with the face of the top surface of the concrete on the sleeper  104  top. 
         [0055]    Before either of the anchoring device  1  or the sealing plate  120  are introduced into the mould, they are connected so as to form an anchoring device assembly, as illustrated in  FIGS. 11 and 12 . The end of the hook-shaped portion of the head  1 A and the stem  1 B each comprise a means for engaging the sealing plate  120 , being in this embodiment, in the form of tabs  130  on the stem  1 B, and lugs  132  on the end of the hook-shaped portion of the head  1 A (although slots would be an alternative). Moreover, the sealing plate  120  comprises a pair of sockets  122  for receiving the lugs  132 , each socket comprising a shoulder  124  for capturing the lug  132  with a ‘snap-fit’. The sealing plate  120  locates (interlocks) between the tabs  130  and lugs  132  and bridges the stem  1 B and the end of the hook-shaped portion to accurately position the sealing plate  120  ready for concrete pouring. In this way, the sealing plate  120  prevents concrete slurry from filling the slot-shaped recess  2 . 
         [0056]    The Y-shaped stem  1 B allows some weight to be saved relative to existing shoulders. Moreover, and possibly more importantly, the Y-shape stem  1 B provides resistance to any loads resulting in a turning moment about a longitudinal axis of the stem  1 B, thereby eliminating the requirement that a portion of the head  1 A be embedded directly in the concrete of the sleeper, as is the case with many shoulders of the prior art, such as the retaining member disclosed in patent GB 1,585,599 for instance. 
         [0057]    The slot shaped recess  2  for the clip  108  extends from its downward facing opening into the head  1 A at an angle relative to the longitudinal axis of the stem  1 B and which is inclined towards a corner defined between the head  1 A and the stem  1 B. In use, this brings the retained clip  108  into near alignment with the stem  1 B (see  FIG. 9 ), aiding retention of the clip  108  by the shoulder  1  by making for a more direct load path to the concrete sleeper  104 . 
         [0058]    A further advantage of the slot shaped recess  2  for the clip  108  extending into the head  1 A at an angle relative to the longitudinal axis of the stem  1 B is that it permits casting of the shoulder  1 , and particularly the slot shaped recess  2 , without need for a core of the type required to form a closed void. Instead, shoulder  1  can be cast in a substantially v-shaped mould cavity, and extracted therefrom without difficulty. 
         [0059]    Retaining members of the type disclosed in patent GB 1,585,599 are fabricated from sheet steel in an involved and staged fabrication process, which included the steps of forming the blank, followed by a staged bending process. This manufacturing process is labour intensive and potentially costly. Casting the shoulder  1  ameliorates this difficulty, and allows the shoulder  1  to include detail features for engaging sealing plate  120 , and for additional material to be included at points which require additional strength. In this way, the end of the hook shaped portion need not be embedded in the rail support element in the way that it is for retaining members of the type disclosed in patent GB 1,585,599. 
         [0060]    In addition to all of the above, the resultant shoulder  1  has a relatively open structure compared with shoulders which define voids and the like, which contributes to weight reduction of the shoulder  1  by requiring less material. 
         [0061]    Railway system construction involves transporting large numbers of components across large distances. Typically the components are transported in high volume containers, such as shipping containers. Such transportation incurs significant transport costs. Indeed, the transportation demands are such that even a slight reduction in component weight can lead to a significant reduction in transportation costs. For example, because some transportation systems are weight restricted, a reduction in the weight of a particular component may mean that a larger number of those components may be transported for a particular weight restriction. 
         [0062]    Throughout the specification and the claims that follow, unless the context requires otherwise, the words “comprise” and “include” and variations such as “comprising” and “including” will be understood to imply the inclusion of a stated integer or group of integers, but not the exclusion of any other integer or group of integers. 
         [0063]    The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement of any form of suggestion that such prior art forms part of the common general knowledge. 
         [0064]    It will be appreciated by those skilled in the art that the invention is not restricted in its use to the particular application described. Neither is the present invention restricted in its preferred embodiment with regard to the particular elements and/or features described or depicted herein. It will be appreciated that the invention is not limited to the embodiment or embodiments disclosed, but is capable of numerous rearrangements, modifications and substitutions without departing from the scope of the invention as set forth and defined by the following claims.