Manufacture of top plate for an elastomeric rail fastening assembly

Abstract

A top plate for an elastomeric rail fastening assembly has a downwardly tapering lower wall terminating in an inwardly-directed lip defining a mouth leading into a well. The cavity of the well extends upwardly to provide the interiors of rail-holding mounts between which a bottom flange of a rail may be located. The mounts have open-ended sockets for receiving spring clips used to hold the rail in position between the mounts, and the sockets and well communicate with one another. This form of top plate allows less metal to be used for its construction, requires less dressing after casting, and precisely locates the sockets with respect to one another.

1 - 4 . (canceled) 
     
     
         5 . A method of manufacturing a top plate for an elastomeric rail fastening assembly or similar device, the top plate defining a well formed in an underside of the top plate and having a mouth, the method comprising forming the top plate by a casting process using a single core attached to an interior wall of a mold to define the well and sockets of the top plate which are to receive rail-holding clips, the core being attached to the interior wall of the mold by way of the mouth of the well prior to passing molten metal into the mold. 
     
     
         6 . A method according to  claim 6 , in which the core has a larger horizontal cross-section inside the mold than the mouth of the well. 
     
     
         7 . A method of manufacturing a top plate for an elastomeric rail fastening assembly, comprising:
 providing a mold having an interior wall,   providing a single core for locating in the mold to define a well and sockets of the top plate which are to receive rail-holding clips,   attaching the core to the interior wall of the mold by way of a mouth of the well, and   pouring molten metal into the mold.   
     
     
         8 . A method according to  claim 7 , wherein the single core includes a body portion that defines the well and also includes two projecting portions which define the respective sockets, wherein the two projecting portions are formed so that the sockets are at predetermined relative positions.