Abstract:
The present invention comprises a railroad tie disposed below the rails to support the rails and comprising a protrusion on a sloped surface of the railroad tie; and a reinforcing plate comprising a groove on a sloped surface of the reinforcing plate, which corresponds to the sloped surface of the railroad tie, wherein the reinforcing plate is coupled with the railroad ties by inserting the protrusion into the groove and opposing the sloped surface of the reinforcing plate to the sloped surface of the railroad tie.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to an apparatus for reinforcing railroad ties and particularly an apparatus for reinforcing railroad ties which disperses a force applied to the side of a railroad tie, thereby preventing railroad ties and/or rails from being deformed or broken and holding rails to the correct gauge, and facilitates installation and repair of railroad ties. 
         [0003]    2. Description of the Related Art 
         [0004]      FIG. 1  is a cross-sectional view of a conventional railroad track including track ballast  10 , rails  20  and railroad ties  30 .  FIG. 2  is a perspective view of a conventional railroad track. 
         [0005]    The railroad ties  30  are members generally laid transverse to the rails  20  and spaced apart from each other, on which the rails  20  are supported and fixed, to transfer the loads from rails  20  to the track ballast  10  and subgrade, and to hold the rails  20  to the correct gauge. Railroad ties  30  have traditionally been made of wood, but concrete is now widely used. The railroad ties  30  are normally laid on top of the track ballast  10 , which supports and holds them in place, and provides drainage and flexibility. The track ballast  10  is packed between, below and around the railroad ties  30 . 
         [0006]    Generally, the rails  20  suffer a force in the travel direction A (hereinafter, “travel-directional force”) and a force in the direction B transverse to the rails  20  (hereinafter, “side-directional force”). The side-directional force generally results from centrifugal force which is generated by the train turning on a curved railroad track. These forces are transferred to the track ballast  10  through the railroad ties  30 . 
         [0007]    When a train travels on the rails  20 , the track ballast  10  which is placed between the railroad ties  30  supports the railroad ties  30  through the front surfaces  30   a  of the railroad ties  30  against the travel-directional force, thereby preventing the railroad ties  30  from being deformed and moved. 
         [0008]      FIG. 3  is a schematic view of the supporting force distribution of a conventional railroad track. 
         [0009]    In a curved railroad track, the track ballast  10  which is placed around the side surface  30   b  of the railroad tie  30  supports the railroad tie  30  through the side surface  30   b  against the side-directional force F. However, because the area of the side surface  30   b , which the track ballast  10  supports, is smaller than that of the front surface  30   a , it is more difficult for the track ballast  10  to support the railroad tie  30  against the side-directional force F than the travel-directional force. Therefore, the rails  20  may be deformed due to deformation or movement of the railroad ties  30  by the side-directional force F. 
         [0010]    When the rails  20  expand during the summer heat, the expanded rails  20  also apply side-directional force to the railroad ties  30  to which the rails  20  are fixed. If the track ballast  10  cannot support the railroad tie  30  sufficiently against the side-directional force, derailment may occur. 
         [0011]    Furthermore, there has been a problem in conventional railroad tracks that the railroad ties cannot be easily and swiftly installed at constant intervals. 
       SUMMARY OF THE INVENTION 
       [0012]    The purpose of the present invention is to provide an apparatus for reinforcing railroad ties which can prevent rails from being deformed by a side-directional force which results from the centrifugal force of a train and/or a side-directional force which results from heat-expanded rails. 
         [0013]    Another purpose of the present invention is to facilitate precise installation of railroad ties at a designated position at constant intervals and swift replacement of damaged railroad ties. 
         [0014]    Another purpose of the present invention is to prevent a reinforcing plate from being separated upward due to vibration of a train by installing a rotary latch on top of railroad ties. 
         [0015]    In order to achieve the above purposes, an embodiment of the present invention is an apparatus for reinforcing railroad ties comprising: a railroad tie disposed below rails to support the rails and comprising a protrusion on a sloped surface of the railroad tie; and a reinforcing plate comprising a groove on a sloped surface of the reinforcing plate, the sloped surface of the reinforcing plate corresponding to the sloped surface of the railroad tie, wherein the reinforcing plate is coupled with the railroad ties by inserting the protrusion into the groove and opposing the sloped surface of the reinforcing plate to the sloped surface of the railroad tie. The railroad tie and the reinforcing plate may be made of ferroconcrete. 
         [0016]    The side of the railroad tie has a trapezoidal shape, and the sloped surface of the railroad tie corresponds to an unparallel side of the trapezoidal shape. The side of the reinforcing plate has an inverted-trapezoidal shape, and the sloped surface of the reinforcing plate corresponds to an unparallel side of the inverted-trapezoidal shape. 
         [0017]    The end surface of the protrusion becomes larger as the protrusion extends toward the end surface of the protrusion, and the bottom surface of the groove becomes larger as the groove extends toward the bottom surface of the groove to correspond to the protrusion. The protrusion is engaged with the groove by moving the reinforcing plate down to the railroad tie arranged under the reinforcing plate. 
         [0018]    The end surface of the protrusion is vertical to the top surface of the railroad tie, and the bottom surface of the groove is vertical to the top surface of the reinforcing plate. 
         [0019]    A rotary latch may be disposed on the top surface of the railroad tie, wherein the rotary latch rotates to prevent the reinforcing plate from moving upward. 
         [0020]    The apparatus for reinforcing railroad ties according to the present invention couples the reinforcing plate with the railroad ties such that the area which the track ballast contacts is increased. Therefore, the present invention can prevent the rails from being deformed due to the deformation or movement of the railroad ties because the supporting force which is applied to the railroad ties against the side-directional force is reduced by the amount of the supporting force applied to the reinforcing plate. Since the present invention can remove the probability of rail deformation, the speed of a train can be increased and the chance of derailment can be reduced. 
         [0021]    When railroad ties are damaged or rails need to be repaired, the reinforcing plate can be easily installed and removed due to the coupling system of the present invention, which can reduce maintenance costs for railroad tracks. 
         [0022]    Furthermore, the rotary latch can prevent the reinforcing plate from being separated upward due to vibration of a train. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         [0023]      FIG. 1  is a cross-sectional view of a conventional railroad track. 
           [0024]      FIG. 2  is a perspective view of a conventional railroad track. 
           [0025]      FIG. 3  is a schematic view of the supporting force distribution of a conventional railroad track. 
           [0026]      FIG. 4  is an exploded view of an apparatus for reinforcing railroad ties according to an embodiment of the present invention. 
           [0027]      FIG. 5  is a perspective view of the apparatus for reinforcing railroad ties according to an embodiment of the present invention. 
           [0028]      FIG. 6  is a side view of the apparatus for reinforcing railroad ties according to an embodiment of the present invention. 
           [0029]      FIG. 7  is a perspective view of the apparatus for reinforcing railroad ties according to an embodiment of the present invention, which is installed in a curved railroad track. 
           [0030]      FIG. 8  is a schematic view of the supporting force distribution of the apparatus for reinforcing railroad ties according to an embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0031]    Hereinafter, an apparatus for reinforcing railroad ties according to an embodiment of the present invention will be explained in more detail with reference to the accompanying drawings. 
         [0032]      FIG. 4  is an exploded view of the apparatus for reinforcing railroad ties according to an embodiment of the present invention.  FIG. 5  is a perspective view of the apparatus for reinforcing railroad ties according to an embodiment of the present invention.  FIG. 6  is a side view of the apparatus for reinforcing railroad ties according to an embodiment of the present invention.  FIG. 7  is a perspective view of the apparatus for reinforcing railroad ties according to an embodiment of the present invention, which is installed in a curved railroad track.  FIG. 8  is a schematic view of the supporting force distribution of the apparatus for reinforcing railroad ties according to an embodiment of the present invention. 
         [0033]    The apparatus for reinforcing railroad ties  500  comprises railroad ties  110  having protrusions  111  and  112 , and a reinforcing plate  210 . The railroad ties  110  and the reinforcing plate  210  may be made of concrete or ferroconcrete. 
         [0034]    The railroad ties  110  are arranged parallel with each other on track ballast  10 . The track ballast  10  is packed between, below and around the railroad ties  110  like conventional railroad tracks. Rails  300  are fixed on top of the railroad tie  110 . The railroad ties  110 , which are laid transverse to the rails  300 , transfer the loads from the rails  300  to the track ballast  10  and hold the rails  300  in their original positions. 
         [0035]    The railroad tie  110  is a hexahedron, and the side  110   c  of the railroad tie  110  has a trapezoidal shape as shown in  FIG. 6 . The railroad tie  110  has the protrusions  111  and  112  which protrude on the opposed sloped surfaces  110   a  and  110   b , which correspond to unparallel sides of the trapezoidal shape. The railroad tie  110  is coupled with the reinforcing plate  210  through the protrusions  111  and  112  as explained below. 
         [0036]    The reinforcing plate  210  is placed between the railroad ties  110 . The side  210   c  of the reinforcing plate  210  has an inverted-trapezoidal shape as shown in  FIG. 6 . The reinforcing plate  210  has grooves  211  and  212 , into which the protrusions  111  and  112  are inserted, on the opposed sloped surfaces  210   a  and  210   b , which correspond to unparallel sides of the inverted-trapezoidal shape. 
         [0037]    As shown in  FIG. 4 , in order to insert the protrusions  111  and  112  into the grooves  211  and  212 , the reinforcing plate  210  is moved down to the railroad ties  110  which have already been arranged on the track ballast  10 .  FIG. 5  shows the reinforcing plates  210  coupled with the railroad ties  110 . 
         [0038]    Because the side shape of the railroad tie  110  is trapezoidal and the side shape of the reinforcing plates  210  is inverted-trapezoidal, the area of the starting point of inserting the reinforcing plate  210  between the railroad ties  110  is larger than that of the ending point, which facilitates inserting the reinforcing plate  210  between the railroad ties  110 . 
         [0039]    In order to prevent the reinforcing plate  210  from being separated from the railroad tie  110 , the end surfaces  111   a  and  112   a  of the protrusions  111  and  112  become larger as the protrusions  111  and  112  extend from the railroad tie  110  to the end surfaces  111   a  and  112   a  of the protrusions  111  and  112 . Additionally, the bottom surfaces  211   a  and  212   a  of the grooves  211  and  212  become larger as the grooves  211  and  212  extend from the sloped surfaces  210   a  and  210   b  to the center of the reinforcing plate  210  to correspond to the protrusions  111  and  112 . 
         [0040]    Here, the end surfaces  111   a  and  112   a , and the bottom surfaces  211   a  and  212   a  do not decline like the sloped surfaces  110   a ,  110   b ,  210   a  and  210   b , but are vertical to the top surface of the railroad tie  110  or reinforcing plate  210 . 
         [0041]    The combination of the side shapes of the railroad tie  110  and reinforcing plate  210 , and the triangular prism shapes of the protrusions  111  and  112  and grooves  211  and  212  prevents the reinforcing plate  210  from moving down excessively between the railroad ties  110 . 
         [0042]    The locations of the protrusions  111  and  112 , and those of the grooves  211  and  212  into which the protrusions  111  and  112  are inserted, become the reference points for coupling the reinforcing plate  210  with the railroad ties  110 , which can enhance the speed and preciseness of coupling them. 
         [0043]    Also, because the railroad ties  110  can be arranged at constant intervals by the reinforcing plates  210  which are inserted between the railroad ties  110 , the reinforcing plate  210  facilitates swift and precise placement of the railroad ties  110  to their designated positions during the installation or repair of the railroad ties  110 . 
         [0044]    In order to prevent the reinforcing plate  210  from being separated upward, a rotary latch  130  may be installed on the top surface of the railroad tie  110  as shown in  FIG. 5 . After the reinforcing plate  210  is coupled with the railroad tie  110 , the rotary latch  130  rotates in the direction illustrated by arrows in  FIG. 5  to be placed on the top surface of the reinforcing plate  210 , thereby blocking the upward movement of the reinforcing plate  210 . In order to remove the reinforcing plate  210  from the railroad ties  110 , the rotary latch  130  rotates in the opposite direction. 
         [0045]    In order to facilitate lifting of the reinforcing plate  210 , a handle  215  may be installed on the top surface of the reinforcing plate  210  and be folded or unfolded on the reinforcing plate  210 . 
         [0046]    As shown in  FIG. 7 , when the railroad track is curved, the railroad ties  110  are arranged in a radial direction and the sloped surfaces of the reinforcing plate  210  are correspondingly formed in the same direction. 
         [0047]    Referring to  FIG. 8 , because both the railroad ties  110  and the reinforcing plate  210  are supported by the track ballast  10 , the supporting force against the side-directional force F is distributed to the reinforcing plate  210  as well as the railroad ties  110 . Therefore, the supporting force on the railroad ties  110  is reduced by the amount of the supporting force applied to the reinforcing plate  210 , thereby preventing the rails  300  from being deformed due to the deformation or movement of the railroad ties  110 . Also, the railroad ties of the present invention can bear larger side-directional force than those of conventional railroad tracks and are deformed less than those of conventional railroad tracks. 
         [0048]    From the above embodiment for the present invention, it is noted that modifications and variations could be made by a person skilled in the art in light of the above teachings. Therefore, it should be understood that changes may be made for a particular embodiment of the present invention within its scope and spirit outlined by the appended claims.