Patent Publication Number: US-6655296-B2

Title: Method of renewing damaged ties of a track

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This application claims the benefit of prior filed provisional application, Appl. No. 60/283,708, filed Apr. 13, 2001, pursuant to 35 U.S.C. 119(e), the subject matter of which is incorporated herein by reference. 
    
    
     This application claims the priority of Austrian utility model, Ser. No. GM 283/2001, filed Apr. 11, 2001, pursuant to 35 U.S.C. 119(a)-(d), the subject matter of which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     The present invention relates, in general, to a method for renewal of damaged ties of a track, wherein base plates, having anchoring holes for passage of fastening elements, are positioned between rail base of a rail and tie and secured from the removal of the damaged tie to the introduction of a new tie for providing a connection upon the rail base. 
     U.S. Pat. No. 5,617,795 describes a tong-shaped apparatus which is provided for gripping base plates and pressed against the rail base of a rail during a replacement of ties. A similar apparatus is described in U.S. Pat. No. 5,048,424 wherein the base plates are secured temporarily by magnets arranged on a vehicle traveling via flanged rollers along the track. 
     Furthermore, U.S. Pat. No. 6,158,353 discloses the connection of the base plates to the rail base through provisional welding of rail spikes. 
     It would therefore be desirable and advantageous to provide an improved method of renewing old ties to obviate prior art shortcomings to carry out in a simple manner. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the present invention, a method includes the steps of inserting, before removal of the damaged tie, into an anchoring hole in both portions of the base plate, disposed respectively adjacent to the rail base, a fastening element which has a contact nose for abutment against the rail base and is connected to the base plate. 
     As a consequence, a connection of the base plate with the rail base can be made in a very simple manner, whereby, in an especially advantageous manner, there is no need to remove the connection after placement of the new tie. This is possible because each longitudinal rail side has a total of four anchoring holes of which one is not utilized for the connection of the base plate with the tie. 
     Suitably, the fastening element is permanently connected to the base plate by welding, e.g., spot welding. After the damaged old tie is replaced by a new tie, rail spikes can be driven into free anchoring holes of the base plate to finalize a connection of the new tie to the rail. 
     According to another feature of the present invention, the fastening element has the configuration of a spike without head and has one end formed with the contact nose. Suitably, the fastening element has a length sized to prevent a lower end of the fastening element to project beyond a rail-distal bottom plane of the base plate, when inserted in the anchoring hole. 
     According to another feature of the present invention, an anchor is placed into the anchoring hole for so cooperating with the fastening element as to effect a forced engagement of the fastening element with the base plate. Suitably, the fastening element and the anchor have complementing tapered lower portions, wherein the lower portion of the fastening element has a diameter which is slightly greater than a diameter of the lower portion of the anchor. 
     According to another aspect of the present invention, a method according to the present invention includes the steps of placing a magnet at each side of a base plate, positioned between the damaged tie and a rail base of a rail, upon a portion adjacent the rail base, for provisional connection of the base plate with the rail base; removing the damaged tie while the magnets remain in place on the base plate; and inserting a new tie underneath the base plate. 
     The use of a magnet for connection of the base plate with the rail base results in a rapid connection, without requiring to carry out a precise centering step for inserting the magnetic fastening elements in an anchoring hole of the base plate. 
     According to another feature of the present invention, the magnet may include two spaced-apart magnet members interconnected by a handle to facilitate placement of the magnet members. Suitably, one magnet member is placed between neighboring anchoring holes, and the other magnet member is placed upon the rail base. Once the new tie is secured to the base plate, the magnet can be removed again. 
     According to another feature of the present invention, the magnet may be connected with a contact nose for abutment against the rail base. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     Other features and advantages of the present invention will be more readily apparent upon reading the following description of currently preferred exemplified embodiments of the invention with reference to the accompanying drawing, in which: 
     FIG. 1 is a partial side elevational view a machine for renewal of ties of a track in accordance with the present invention; 
     FIG. 2 is a plan view of the tie renewal machine of FIG. 1; 
     FIG. 3 is a cross section through a rail connected with a base plate utilizing a first variation of a fastening element; 
     FIG. 4 is a plan view of the base plate; 
     FIG. 5 is a fragmentary sectional view of a second variation of a fastening element; 
     FIG. 6 is a fragmentary sectional view of a third variation of a fastening element; and 
     FIG. 7 is a fragmentary sectional view of a fourth variation of a fastening element. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Throughout all the Figures, same or corresponding elements are generally indicated by same reference numerals. 
     Turning now to the drawing, and in particular to FIGS. 1 and 2, there is shown a track maintenance machine  1  for removing single damaged ties  2  and placement of new ties  3 . The machine  1  includes a machine frame  5  supported at its ends by two undercarriages  4 . Provided for the forward travel of the machine  1  is a motive drive  6  which, like all the remaining drives of the machine  1 , can be activated by a central power unit  7 . For the purpose of a better view of the work units, a central control device  9  is arranged in an operator&#39;s cab  8  immediately above the work units. 
     Disposed between the two undercarriages  4  is a tie exchange apparatus  10  which is vertically and transversely displaceable by drives and shiftable in longitudinal direction of the machine by a drive  11  along a longitudinal guide  12  connected to the machine frame  5 . Two grippers  13 , movable towards one another in the longitudinal direction, are connected to the tie exchange apparatus  10  for picking up old ties  2  in the tie end area. Provided as a further work unit is a ballast clearing device  15  which includes vertically and transversely adjustable clearing members  14  and is supported by a tool frame  16  which can travel on the track  18  via an undercarriage  18  in the region of the tie exchange apparatus  10 . 
     In the end region opposite the undercarriage  17 , the tool frame  16  is hingedly supported on the machine frame  5  in the area of a point of articulation  19  and connected to a longitudinal displacement drive  20 . The undercarriage  17 , mounted to the tool frame  16 , and the immediately adjacent ballast clearing device  15  are arranged between the tie exchange device  10  and the point of articulation  19  which is supported by longitudinal guides  21 , connected to the machine frame  5 , for displacement in the longitudinal direction. Linked to the tool frame  16  in the area of the clearing member  14  is a track lifting device  25  which has a lifting member  24  to rest laterally against a rail  23  of the track  18 . Furthermore, a lifting drive  26  is linked to each longitudinal side of the tool frame  16  and has an upper end for connection to a carriage  27  which is supported by a guide  28  of the machine frame for travel in longitudinal direction. Located underneath the operators&#39; cab  8  in the region of each rail  23  is a vertically adjustable tamping unit  29 . 
     A tie deposit unit  30  is provided for commonly depositing old ties  2  as well as new ties  3  and is disposed centrally with respect to a direction transversely to the machine. The machine frame  5  has an opening in the region of the tie deposit unit  30  for passage of a tie gripper  31 . 
     Located at the forward end of the machine  1 , as viewed with regard to the operating direction indicated by arrow  40 , underneath an operators&#39; cab  32  is a welding robot  33  which is vertically, longitudinally and transversely adjustable by drives and suitable for spot welding. A vertically adjustable magnetic gripper  22  is associated with the welding robot  33 . A receptacle  34  contains fastening elements  35 . 
     During tie renewal operation, two fastening elements  35  are taken by an operator located in the operator&#39;s cab  32  and inserted at each longitudinal rail side in a free anchoring hole  49  of a base or tie plate  39  (see FIG.  3 ), wherein a contact nose  51  of the fastening element  35  rests against an adjacent edge of the rail base  52  of the rail  23 . Next, the welding robot  33  carries out a spot weld  38  for welding the fastening element  35  to the base plate  39 . Subsequently, a spike extractor, not shown in more detail, pulls out the rail spikes from the tie  2  to be replaced. 
     Subsequently, the old tie  2  is pulled laterally from the track  18  with the aid of the tie exchange device  10  while the rails  23  are slightly raised by the track lifting device  25 . The pertaining base plates  39  remain hereby in their original position on the rails  23  as a consequence of the fastening elements  35  —as shown in FIG.  3 . Subsequently, a new tie  3  is pushed underneath the cleared base plates  39 , again with the aid of the tie exchange device  10 . After the new tie  3  inserted in the track  18  has been tamped, rail spikes are driven into the new tie  3  through the free anchoring holes  49  of the base plate  39  in order to establish a final rail/tie connection. 
     As shown in FIGS. 3 and 4, only one anchoring hole  49  is used in each longitudinal rail side for insertion of a spike-like fastening element  35  with a contact nose  51  resting against the rail base  52 . The fastening element  35  may be suitably made by separating the head-adjacent portion of an old, unusable rail spike. The length of the fastening element  35  is so sized that its lower end  54  does not project beyond a lower plane  50  of the base plate  39 . 
     According to a variation of a fastening element  35 , shown in FIG. 5, an anchor  55  is placed together with the fastening element  35  into the anchoring hole  49  of the base plate  39 . The anchor  55  as well as the lower portion  56  of the fastening element  35  taper in downward direction. As the lower portion  56  has a diameter which is slightly greater than the diameter of the anchor  55 , the insertion of the fastening element  35  automatically results in a forced engagement with the base plate  39 . 
     A fastening element  35 , shown in FIG. 6, includes two magnets  57  which are spaced from one another in a direction transversely to the track and interconnected by a handle  58 . In order to implement a temporary connection between base plate  39  and the rail  23 , the operator so places the fastening element  35  that the one magnet  57  rests on the base plate  39  between the anchoring holes  49  and the received rail spikes  52 , respectively, whereas the second magnet  57  is disposed on the rail base  52 . After final connection of the base plate  39  and the new tie, the fastening elements  35  are removed again. 
     FIG. 7 shows a further variation of a fastening element  35  with a magnet  57  disposed on the base plate  39  and connected with a contact nose  51  for abutment against the rail base  52 . A handle  58  facilitates the correct positioning of the fastening element  35  as well as the removal thereof. 
     While the invention has been illustrated and described as embodied in a method of renewing damaged ties of a track, it is not intended to be limited to the details shown since various modifications and structural changes may be made without departing in any way from the spirit of the present invention. the embodiments were chosen and described in order to best explain the principles of the invention and practical application to thereby enable a person skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated.