Patent Publication Number: US-6213407-B1

Title: Two-piece rail seal clip and tool for installing same

Description:
SUMMARY OF THE INVENTION 
     This invention relates to an apparatus for securing rail seal elements on opposite sides of a rail. 
     In rail track construction, it is frequently necessary and/or desirable to align the rail head with adjacent road surfaces in order to facilitate movement of pedestrian and vehicular traffic. This commonly occurs at level crossings, and in light rail systems where rail and vehicular traffic share a common right of way. In order to prevent fouling of the rails in these installations, it is common practice to install rubber or resilient polymer rail seals which serve to seal a space between each rail and the adjacent road surface. Typical examples of such rail seals can be seen in U.S. Pat. No. 4,461,421 (Maass). Rail seals of the type described in U.S. Pat. No. 4,461,421 (Maass) have the advantages of being easy to manufacture in large quantity and at low cost, while offering an effective means of preventing fouling of the rails by ice, snow or other foreign matter. 
     In order to further reduce the costs of maintaining the road surface, it is frequently necessary to install the rail seals on each side of the rails prior to construction of the adjacent road surfaces. The rail seals then serve as forms during the pouring of concrete or laying of asphalt for the road surface. 
     However, in order to retain the rail seals on each side of the rails during construction and throughout the service life of the crossing, it is necessary to provide some means of securing the rail seals in place. For this purpose, it is known to employ a generally U-shaped spring clip  4  which is designed to be inserted under the rail  1  between adjacent ties. The ends  5 ,  6  of the spring clip  4  are then maneuvered into position to press the rail seals  2 ,  3  against the rail  1  (see FIG.  1 ). This arrangement suffers from numerous disadvantages. In particular, in order to install the spring clip  4 , a quantity of ballast (crushed stone) must be removed from between adjacent ties. This is time consuming and labor intensive thereby increasing costs. Concerns have also been raised that the removal of ballast in this way might undermine the footings of the rail, thereby leading to more rapid degradation of the track. Additionally, in order to generate sufficient holding forces, the spring clips typically need to be made of spring steel, which greatly increases their cost. Finally, experience has shown that once such spring clips have been installed, it is extremely difficult to remove them later, for example in order to conduct maintenance or upgrading of the rail. 
     An object of the present invention is to provide a clip for securing rail seals to a rail which overcomes the above-noted disadvantages of the prior art. 
     A further object of the present invention is to provide a clip which can be installed with minimum labor, and while minimizing any disruption of the rail ballast. 
     It is a further object of the present invention to provide a clip which can be readily removed. 
     Accordingly, an aspect of the present invention provides a clip for securing a rail seal to a rail, the clip comprising a generally L-shaped clip bar having a clamping arm and an elongate connector arm extending from one end of the clamping arm and capable of passing under the rail, a clip arm removably slidable on the connector arm, and a locking mechanism capable of releasably locking the clip arm against sliding movement along the connector arm. In use, the clip arm is removed from the connector arm so that the connector arm can be passed under the rail with minimum disruption of the ballast. The clip arm is then slid back onto the connector arm, and the assembled clip is then oriented so that the rail and the rail seal are positioned between the clamping arm and the clip arm. The clip arm is then slid on the connector arm toward the clamping arm so as to tightly press the rail and rail seal therebetween. Finally, the clip arm is locked onto the connector arm to prevent the clip from releasing the rail and the rail seals. 
     In an embodiment of the invention, the clip arm is formed as a curvilinear body. A contact pad designed to engage an outer surface of a rail seal is disposed near one end of the body, and an opening capable of slidably receiving the connector arm is provided near an opposite end of the body. 
     The clip arm further includes a bearing surface between the contact pad and the opening. By this means, the clip arm is slidable on the connector arm toward the clamping arm in response to a force acting on the bearing surface. 
     The locking mechanism comprises a plurality of notches in an upper surface of the connector arm, and an edge or corner of the opening in the clip arm. By this means, a resilient force of a rail seal secured by the clip causes the clip arm to rotate until the corner of the opening engages one of the notches of the connector arm, thereby preventing sliding motion of the clip arm away from the clamping arm. 
     A tool notch is provided near a free end of the connector arm of the clip bar. 
     A tool capable of being removably coupled to the connector arm and the clip arm is used for forcibly sliding the clip arm toward the clamping arm to clamp the rail seal element against the rail, and for engaging the locking means to prevent undesired motion of the clip arm away from the clamping arm. 
     The tool comprises a pivot pin capable of being removably engaged in the tool notch of the connector arm, and cam surfaces capable of engaging the contact face of the clip arm. In this case, movement of the clip arm toward the clamping arm is caused by inserting the pivot pin into the tool notch and thereafter pivoting the tool about the pivot pin toward the clamping arm. Subsequent pivoting of the tool away from the clamping arm causes the locking mechanism to automatically engage to prevent the clip arm from moving away from the clamping arm. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Further features and advantages of the present invention will become apparent from the following detailed description, taken in combination with the appended drawings, in which: 
     FIG. 1 is a cross-sectional view of a rail and a pair of rail seals secured to opposite sides of the rail by means of a conventional spring clip; 
     FIG. 2 is a cross-sectional view of a pair of rail seals secured to opposite sides of a rail by means of a clip in accordance with of the present invention; 
     FIG. 3 a  is a front view of the clip of FIG. 2; 
     FIG. 3 b  is a partial cross-sectional view illustrating the operation of the locking mechanism of the embodiment of FIG. 2; 
     FIG. 3 c  is a cross-sectional view showing the lower portion of the second clip member of the embodiment of FIG. 2; 
     FIG. 4 is an isometric view of a tool for installing and removing the clip of FIG. 2; 
     FIGS. 5 a  to  5   e  are cross-sectional views similar to FIG. 2 showing the steps for installing the clip of FIG. 2 using the tool of FIG. 4; and 
     FIGS. 6 a  and  6   b  are cross-sectional views similar to FIG. 2 illustrating the steps for removing the clip of FIG. 2 using the tool of FIG.  4 . 
    
    
     DETAILED DESCRIPTION 
     Referring to FIGS. 2 and 3 a  to  3   c , a clip  7  in accordance with the present invention comprises a generally L-shaped bar  8 , an arm  9  removably slidable on the bar  8 , and a locking mechanism generally indicated at  10 . As shown in FIG. 4, a setting tool  11  for setting the clip  7  on a rail  1  and rail seals  2 ,  3  comprises a bifurcated cam body generally indicated at  12  mounted on a free end of a lever arm  13 , and a pivot pin  14  disposed on a nose  15  of the cam body  12 . 
     The bar  8  can conveniently be formed from a single piece of mild steel barstock bent to form an L-shaped body having arms of unequal length. The shorter of the two arms defines a clamping arm  16  and is designed to engage a rail seal  2  on one side of the rail  1 . For this purpose, the clamping arm  16  can conveniently be provided with a rounded contact pad  17  (FIG. 3 a ) disposed at the free end of the clamping arm  16 . By this means, the clamping arm  16  can be forcefully pressed against a face of the rail seal  2  without causing undue damage or distortion of the rail seal  2 . The longer of the two arms defines a connector arm  18  which is of sufficient length to extend under the rail  1  and rail seals  2 ,  3  as shown in FIG. 2. A plurality of locking notches  19  are provided on an upper surface  20  of the connector arm  18 , and define a portion of the locking mechanism  10 . Finally, a tool notch  21  is provided near a free end of the connector arm  18  for receiving the pivot pin  14  of the setting tool  11 . 
     The arm  9  can conveniently be formed of a suitable piece of mild steel strap bent to define an arcuate body. A concavo-convex upper end of the body defines a contact pad  22  designed for bearing against a surface of rail seal  3 . A substantially flat central portion of the arm defines a bearing surface  23  against which the tool  11  can be used to move the arm  9  toward the rail seal  3  and simultaneously engage the locking mechanism  10  to lock the arm  9  in place on the connector arm  18 . A straight, flat lower end  24  of the body includes an opening  25  for slidably receiving the connector arm  18  of the bar  8 . As seen in FIG. 3 c , the width w of the opening  25  is preferably sufficiently large to provide a small clearance with the sides of the connector arm  18 , so that the arm  9  can easily slide along the connector arm  18 , but an acceptable alignment between the clamping arm  16  and the clip arm  9  can be maintained. The height h of the opening  25  is sufficiently greater than the height of the connector arm  18  so that the clip arm  9  is capable of pivoting through a small angle, as shown in FIG. 3 a . As described in greater detail below, this pivoting motion of the clip arm  9  is essential to successful operation of the locking mechanism  10 . 
     As mentioned above, the locking notches  19  provided on the connector arm  18  define a portion of the locking mechanism  10 . The remaining portions of the locking mechanism are defined by the upper and lower interior surfaces  26  and  27  of the opening in the clip arm  9 , and the upper and lower corners  28  and  29  of the opening  25  which abut the top and bottom surfaces of the clip arm  9  (FIG. 3 b ). 
     Referring now to FIG. 4, in accordance with the present invention, the setting tool  11  for setting the clip  7  on a rail  1  and rails seals  2  and  3  includes the bifurcated cam body  12  having cam surfaces  30  (one shown) mounted on a free end of the lever arm  13 , and the pivot pin  14  disposed on the nose  15  of the cam body  12 . The lever arm  13  is formed of any suitable material, such as, for example a piece of steel pipe. Similarly, the length of the lever arm  13  can be selected as desired commensurate with the need to provide adequate leverage to properly set the clip, while allowing adequate portability of the tool. In practice, a lever arm in the range of between 40 and 50 inches in length has been found to be beneficial. The cam body  12  is designed such that, when the pivot pin  14  is inserted into the tool notch  21  of the connector arm  18 , then the cam surfaces  30  will bear against the bearing surface  23  of the clip arm  9 . In this condition, pivoting of the setting tool  11  in the direction of arrow T (FIG. 5 d ), will cause the cam body  12  and pivot pin  14  to generate very high forces simultaneously acting on the bar  8  and the clip arm  9  to force the arm  9  toward the clamping arm  16  against the resistance of the rail seals  2  and  3  on opposite sides of the rail  1 . 
     Once the clip has been set in this manner, the pivot pin  14  can be removed from the tool notch  21  of the connector arm  18 , and the setting tool  11  removed for reuse with another clip  7 . 
     The method of setting the clip  7  onto a rail  1  and rail seals  2  and  3 , and the operation of the locking mechanism  10 , will now be described with reference to FIGS. 5 a - 5   e . As an initial step (FIG. 5 a ), the connector arm  18  of the bar  8  is slid under the rail  1  and rails seals  2  and  3 , between adjacent ties, until the contact pad  17  of the arm  16  bears “hand-tight” against the rail seal  2 . Typically, this step can be quickly and easily accomplished with minimal use of tools, and with minimum disruption of ballast. The clip arm  9  is then slid onto the arm  18  (FIG. 5 b ) until the pad  22  bears “hand-tight” against the opposite rail seal  3 . At this stage, the setting tool  11  can be used to set the clip  7 , and thereby tightly clamp the rail seals  2  and  3  and rail  1  between the clamping arm  16  of the clip bar  8  and the contact pad  22  of the clip arm  9  (FIGS. 5 d - 5   e ). 
     As described above, pivoting the setting tool  11  in the tool notch  21  causes the cam surfaces  30  of the cam body  12  to apply force to the bearing surface  23  of the clip arm  9 . This force is distributed between the upper and lower ends of the clip arm  9 , thereby causing compression of the rail seals  2  and  3  between the clamp arm  16  and the clip arm  9 , and rotation of the clip arm in the direction of arrow R (FIG. 5 d ) as the lower end  24  continues to advance. Rotation of the arm  9  is limited by the height h of the opening  25 , i.e. the arm  9  will rotate until the upper and lower interior surfaces  26  and  27  of the opening  25  contact the upper and lower surfaces of the connector arm  18 . In this condition, the upper corner  28  engages one of the notches  19 , and contact between the lower corner  29  and the lower surface of the connector arm  18  prevents disengagement of the upper corner  28 , so that rearward movement of the lower end  24  of the clip arm  9  (and thus releasing the compression of the rail seals  2  and  3  within the assembled clip  7 ) is prevented. 
     If it is desired to remove the clip arm  9  from the connector arm  18 , then it is necessary to cause disengagement of the upper corner  28  of the opening  25  from its corresponding notch  19  on the connector arm  18 . This can be accomplished by applying a force couple to the lower end  24  of the clip arm  9  so as to cause (by a combination of compression of the rail seals  2  and  3  and elastic flexure of the clip arm  9 ) rotation of the lower end  24  in a direction indicated by arrow S in FIG. 6 a . This rotation causes disengagement between the lower corner  29  of the opening  25  and the lower surface of the connector arm  18 , thereby allowing the upper corner  28  to rise out of engagement with its corresponding notch  19  (see FIGS. 6 a  and  6   b ). 
     According to the present invention, removal of the clip arm  9  is accomplished using a releasing tool  31  of the type illustrated in FIG.  4 . In the illustrated embodiment, the releasing tool  31  comprises a bifurcated hook  32 , and a pressure bar  33  mounted on a second end of the lever arm  13 . Conveniently, the hook  32  and the pressure bar  33  are mounted on the end of the lever arm  13  opposite the end carrying the setting tool  11 . The hook  32  is defined by a pair of hook arms  34  and  35  arranged to straddle the connector arm  18  when in use. The hook  32  and pressure bar  33  are designed to cooperatively engage opposite sides of the lower end  24  of the clip arm  9 , as shown in FIGS. 6 a  and  6   b.  In this connection, rotation of the releasing tool  31  in the direction of the arrow U will cause rotation of the lower end  24  of the clip arm  9 , which releases the arm  9  as described above. 
     Those skilled in the art will appreciate that various modifications may be made without departing from the scope of the invention as defined by the appended claims. Thus it will be understood that the above-described embodiments are intended to be illustrative, rather than limiting of the present invention.