Abstract:
An actuating system for operating transverse doors of a railroad hopper car. The mechanism includes an operating member which is coupled to a door or doors of the car by a shaft and a linkage which couples a power source to the operating member, where the operating member rotates to move the door away from the hopper. The mechanism can operate doors which open in opposed direction with a single power source. The mechanism can be used in new car construction, and can be retrofitted onto existing hopper cars.

Description:
CROSS REFERENCE TO RELATED APPLICATONS 
   This application claims benefit from U.S. Provisional Application Ser. No. 60/476,940, filed Jun. 9, 2003, which application is incorporated herein by reference. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates generally to an apparatus for opening the rotating doors of a railroad hopper car, and, in particular, to a novel apparatus capable of opening transverse doors on a railroad car. 
   2. Description of the Prior Art 
   A common type of railroad freight car in use today is the freight car of the type wherein the load is discharged through hoppers in the underside of the body. Such cars are generally referred to as covered hopper cars and are used to haul coal, phosphate and other commodities. 
   After hopper cars are spotted over an unloading pit, the doors of the hoppers are opened, allowing the material within the hopper to be emptied into the pit. 
   Hopper cars, which may be covered, are usually found with one of two hopper configurations: transverse, in which the doors closing the hoppers are oriented perpendicular to the center line of the car; or longitudinal, in which the doors closing the hoppers are oriented parallel to the center line of the car. An example of a hopper car with transverse doors is shown in U.S. Pat. No. 5,249,531, while an example of a hopper car with longitudinal doors is shown in U.S. Pat. No. 4,224,877. 
   Prior art references which teach operating mechanisms for opening and closing hopper doors include U.S. Pat. Nos. 3,596,609; 4,741,274; 3,187,684; 3,611,947; 3,786,764; 3,815,514; 3,818,842; 3,949,681; 4,222,334; 4,366,757; 4,601,244; 5,823,118; and 5,249,531. There are several disadvantages to the hopper door operating mechanisms described in some of the aforementioned patents. One problem is that some of the prior art mechanisms are designed such that each actuating mechanism is connected to doors from two separate hoppers. Thus, if the mechanism fails, it affects the operation of two hoppers. Another disadvantage of some of the above described hopper door mechanisms is that the operating mechanisms limit the distance of the door motion, thus limiting the open area of the car&#39;s bottom. This arrangement slows the unloading process and causes additional costs and potential damage to the car due to increased period in thaw sheds. A further disadvantage of some of the prior art hopper door mechanisms are that they are designed for new railcar construction. 
   SUMMARY OF THE INVENTION 
   It is therefore an object of the present invention to provide an automatic mechanism for actuating the discharge doors of a hopper car which can quickly empty the contents. 
   It is a further object of the present invention to provide an actuating mechanism for hopper car doors which can be used in new car manufacturing as well as can be retrofitted to existing cars. 
   It is a still further object of the present invention to provide an actuating mechanism for a hopper car with transverse doors that can simultaneously open all of the doors regardless of the direction of opening. 
   It is also an object of the present invention to provide an operating mechanism for hopper car doors using a single cylinder which can be mounted at either end of the railcar. 
   It is a still further object of the present invention to provide an actuating mechanism for hopper car doors in which each door assembly has a positive over-center locking feature to securely close the doors. 
   These and other objects of the present invention will be more readily apparent from the descriptions and drawings which follow. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an elevational view of a standard three pocket hopper car having transverse doors onto which the door actuating mechanism of the present invention may be incorporated; 
       FIG. 2  is a fragmentary elevational view, taken along a longitudinal axis of a railroad hopper car having transverse doors, showing the actuating mechanism of the present invention in different stages of operation; 
       FIG. 3  is a sectional view of the door actuating mechanism of the present invention taken along line  3 — 3  of  FIG. 2 ; 
       FIG. 4  is a fragmentary elevational view of another embodiment of the actuating mechanism; 
       FIGS. 5A–B  taken together, is an elevational view, taken along a longitudinal axis of a railroad hopper car having transverse doors, showing the reversing mechanism of the embodiment shown in  FIG. 4 ; 
       FIGS. 6A–B  taken together, is a top view of the mechanism shown in  FIGS. 5A–B  in the closed position; 
       FIG. 7  is a sectional view of the mechanism shown in  FIGS. 5A–B  taken along line  7 — 7 ; 
       FIGS. 8A–C  each show a front and side view of different components of the present invention; and 
       FIG. 9  is an elevational view of an air cylinder of the actuating mechanism shown in  FIG. 3 . 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Referring now to  FIG. 1 , there is shown a typical three pocket railway hopper car, generally designated at  2 , which may be equipped with a preferred embodiment of the present invention. Car  2  is provided with a plurality of hopper units  4 , a plurality of wheels  5 , and a longitudinally extending center sill  6 . Wheels  5  are mounted on a series of truck axles  7 . An air cylinder  8  is mounted to car  2  on the underside of sill  6  to provide power for the mechanism of the present invention. The operation of air cylinder  8  is well known in the art, and it is within the scope of the present invention to use any suitable power source (electric, liquid, steam) to operate cylinder  8 . Each hopper unit  4  is provided with a door  9  which is moveable to open and close each hopper unit  4 . 
   The mechanism of the present invention suited for use on a railway hopper car such as shown in  FIG. 1  is most clearly shown in  FIGS. 2 and 3 . An operating member  22  ( FIG. 8A ), with a bifurcated section having arms  22   a–b , is rotatably coupled to a pair of mounts  23 , which are affixed to the underside of center sill  6  of car  2 , by a pair of extensions or shafts  24  extending outwardly from each arm of member  22 . Extending between arms  22   a–b  from a central area  29  of member  22  is a coupling section  30 . Section  30  contains an aperture  32 . A lever  34  is connected between section  30  and an operating beam  36  by a pair of pins  40 . 
   The ends of operating member  22  opposite the end containing shafts  24  each contain an aperture  58  and are each rotatably coupled to a connecting shaft  60  ( FIG. 8B ) having a cylindrical element  62  containing a through hole  64  at one end and a cylindrical element  66  containing a through hole  68  at its opposite end. Element  62  is rotatably held in position by a pin  70  through apertures  58  of member  22 . The opposite end  66  of lever  60  is rotatably coupled to a door spreader  74  of each door  9  by a bifurcated clevis  76  having arms  76   a–b  by a pin  78 . Clevis  76  also contains an extended threaded section  80 . 
   Clevis  76  is rotatably coupled to door spreader  74  of each door  9  such that the door actuating mechanism can open each hopper unit  4 . Each door  9  has a door spreader  74  affixed thereto by welding or any similar attachment means known in the art. Clevis  76  is coupled to spreader  74  of door  9  by inserting threaded section  78  through an aperture  82  of a bracket  84  attached to door spreader  74  and fastening them together with a nut  88 , as can be seen clearly in  FIG. 2 . 
   The operation of the door actuating mechanism of the present invention can now be described as follows. Cylinder  8  is coupled to operating beam  36  by lever  34 . When cylinder  8  is activated, beam  36  is shifted to the left as shown in  FIG. 2 , causing lever  34  to push on section  30  of operating member  22 . Further movement of beam  36  causes member  22  to rotate about shafts  24 , which causes shaft  60  to rotate about pin  70 , which couples element  62  of shaft  60  to member  22 . 
   As beam  36  continues to move, the rotation of member  22  about shafts  24  causes shaft  60 , which is coupled to door  9 , to move to the left as shown in  FIG. 2 . This rotation causes door  9  to begin to open, as can be seen at arrow A in  FIG. 2 . Continued movement of beam  36  causes door  9  to open completely as shown at arrow B. The closing of door  9  is accomplished by reversing the movement of beam  36 , causing the mechanism to operate in the reverse manner as previously described. 
   The device of the present invention creates an over center latch for each door, adding a positive safety to the design. Referring now to  FIG. 2 , when the device of the present invention is in its closed position, an over center latch is created as pin  78  crosses through a plane passing through the centers of extensions  24  and pin  70  which supports shaft  60  in the closed position. As door  9  opens, shaft  60  crosses through this plane, releasing the over center latch and allowing door  9  to shift to the left, as shown at arrow A in  FIG. 2 . Aided in part by the weight of the material within hopper  4 , door  9  opens completely to the position shown at arrow B. Note that door  9  is located a significant distance away from hopper  4  at arrow B, allowing the material within hopper  4  to empty quickly. 
     FIG. 4  is a representation of the present invention shown on another type of hopper door. The connecting shaft of this embodiment has been removed from  FIG. 4  for clarity. Note that throughout the drawings, like elements are designated with like reference numbers. 
   Referring now to  FIG. 4 , hopper door  9 ′ is shown in its closed position, with member  22  in its over center latch location as shown at arrow A. Coupling section  30  of member  22  is directly fixed to operating beam  36  by a pin  100 . As beam  36  is shifted to the left in  FIG. 4 , member  22  rotates about shafts  24  which are rigidly fixed within mounts  23 , and travels to the position shown at arrow B. Connecting shaft  60 ′ ( FIG. 8C ), which is connected to member  22  by cylindrical end  62 ′ between arms  22   a–b  by pin  70  through aperture  64 ′, and to door  9 ′ at its other end by a flattened extension  102  which fits within clevis  76  and is coupled for rotation by pin  78  through aperture  106 , serves to open door  9 ′. At this position, hopper door  9 ′ is opened completely. 
   The reversing mechanism of the present invention for actuating doors which operate in the opposite direction as the door shown in  FIGS. 2 and 4  is most clearly shown in  FIGS. 5–7 . Operating member  22  is rotatably coupled by outwardly extending shafts  24  to a pair of extensions  23  which are rigidly affixed to the underside of center sill  6 . One end of a pair of levers  120  are rotatably coupled to outwardly extending coupling section  30  of member  22 , while a second lever  122  is rotatably coupled between the opposite ends of levers  120 . Lever  122  is fixed for rotation in its central region about a shaft  124  which is affixed to a portion of the underside of center sill  6 . The opposite end of lever  122  is rotatably coupled between the ends of a pair of third levers  130 . The opposite ends of levers  130  are fixed for rotation to operating beam  36  by a fulcrum  140 , which is rigidly affixed to operating beam  36 . 
   The operation of the reversing mechanism of the present invention can now be described. When the mechanism is activated by applying power to cylinder  8 , operating beam  36 , which is coupled to cylinder  8 , is shifted from the closed position to open position, in the direction shown by arrow A in FIGS.  5 A–B and  6 A–B to shift door  9  from its closed position. Fulcrum  140  shifts to the left in  FIG. 5A , causing levers  130  to shift to the position shown at  130 ′. This motion causes lever  122  to rotate counterclockwise about shaft  124  to the position shown at  122 ′. Levers  120  move in the opposite direction from operating beam  36  to the position shown at  120 ′, causing operating member  22  to rotate clockwise about shafts  24  by virtue of the connection of shafts  120  to outwardly extending portion  30 . As shaft  60 ′ shifts through the plane through the centers of pin  70  and extensions  24 , the over center latch is released, allowing hopper door  9 ′ to open completely, aided by the weight of the contents in the hopper. The closing of door  9 ′ is accomplished by reversing the travel of operating beam  36 . 
   The device of the present invention can be used in both new car construction and also in retrofitting existing cars. For cars having transverse doors, preferably one mechanism is used for each door. As at least one door opens in the opposite direction, as shown in  FIG. 1 , the reversing mechanism taught in this invention will be used for doors which operate in reverse. 
     FIG. 9  shows an air cylinder which can operate the mechanism of the present invention when it is not possible to directly couple the cylinder to the actuating beam. Referring now to  FIG. 9 , a cylinder  8  is coupled to actuating beam  36  by a lever  200 . Lever  200  is fixed for rotation about a pivot  202 . When cylinder  8  is activated, lever  200  turns about pivot  202  in a clockwise direction, causing beam  36  to travel in the direction shown by arrow A. Using this mechanism, cylinder  8  can be mounted on either end of car  2 , as actuating beam  36  can be made to travel in either direction by using either direct coupling or lever  200 . 
   In the above description, and in the claims which follow, the use of such words as “clockwise”, “counterclockwise”, “distal”, “proximal”, “forward”, “rearward”, “vertical”, “horizontal”, and the like is in conjunction with the drawings for purposes of clarity. As will be understood by one skilled in the art, the mechanisms will operate on hopper doors which open in opposite directions, and thus will use opposite terminology. 
   While the invention has been shown and described in terms of a preferred embodiment, it will be understood that this invention is not limited to this particular embodiment and that many changes and modifications may be made without departing from the true spirit and scope of the invention as defined in the appended claims.