The present invention relates to railroad freight cars useful for carrying motor vehicles, and particularly to end doors for such cars, for preventing unauthorized access to motor vehicles being carried.
Railroad freight cars have long been used for transporting newly manufactured motor vehicles long distances from the point of manufacture or a port of arrival to cities where dealerships are located or to railroad terminals where the motor vehicles are loaded onto trucks for transport over highways to the locations of dealerships.
In order to avoid pilferage or vandalism of motor vehicles and to protect motor vehicles from airborne hazards, many railroad freight cars designed to carry motor vehicles are enclosed and include roofs and end doors.
Such railroad freight cars include doors at either end of the car to prevent unauthorized access to motor vehicles carried within the car. Some such railroad freight cars include pairs of doors that are hinged at opposite sidewall corners of the car, with the doors meeting each other at the centerline of the car and being latched to the end sill and roof of the car to keep them closed. In the past, however, thieves have been known to gain access to motor vehicles carried within such cars by applying significant force to the edges of the end doors of such cars, where the doors meet each other at centerline of an end of the freight car. In response, the American Association of Railroads has established standards for the amount of force that the end doors of such a railroad freight car must successfully be able to resist.
While the doors of a railroad freight car must be functional to prevent access to the cargo within an enclosed car, it is always desirable to reduce the tare weight of a car when practical, in order to avoid the expense of fuel for hauling anything other than freight-earning cargo. Railroad freight car and doors have therefore recently been built of composite materials in order to reduce the weight of those doors, with the result that some such doors are more flexible and thus more susceptible to being pulled open than were the heavier, stronger doors built in the past.
What is needed, then, is a door for enclosing cargo within a railroad freight car that is not only light in weight but also resistant to being pulled open by a moderate amount of brute force.
The present invention overcomes some of the aforementioned shortcomings of prior art railroad cars by providing a railroad freight car including a pair of end doors that provide ample resistance to being pulled open by thieves or vandals.
A railroad car that is one embodiment of the invention claimed herein includes end doors of lightweight composite materials, each door including stiffening structures along the margins that meet each other at the centerline of the car.
In one embodiment of the present invention, a pair of end doors includes latches to engage the car body at the top and bottom of the doorway at the end of the car, and interlocking members are mounted on a margin of each door in position to engage the margin of the adjacent door of the pair between the top and bottom latches.
The foregoing and other objectives and features of the invention will be more readily understood upon consideration of the following detailed description of the invention, taken in conjunction with the accompanying drawings.
Referring first to
As may be seen in
At least a door panel 38 of the door 22 and a door panel 40 of the door 24, and desirably all the panels of each of the doors 22 and 24, may be of composite material construction including a core 39 of a light, yet strong material such as balsa wood surrounded by a skin 41 of a composite material such as fiber-reinforced plastic resin.
As shown in
The door stiffening structure may also include an inner reinforcing member 46 extending vertically along a margin of the closure mating side 32 of the door 24 on its interior side, as shown in
The outer reinforcing plate 42 and inner reinforcing member 46, separated from each other by the door panel, are spaced apart from the neutral axis of the door and absorb the highest stresses to resist bending in the door panel 38 or 40.
A pair of door engagement members 52 and 54 is carried on the interior of the door 24 along the closure mating side 32 and may be welded to the top of the “hat” shape of the reinforcing member 46. Each door engagement member has a relatively wide base and is tapered to a relatively narrow outer end, so the wide base can carry any stresses to a larger area of the inner reinforcing member 46.
Retainer pins 56 and 58 are located at the top end and bottom end, respectively, of the closure mating side 32 of the door 24 and are captured by respective hooks on the roof 18 and the end sill 20 as the door 24 is moved through the last few inches before it is completely closed toward the door 22 and the centerline of the car 10. Thus, when the door 24 is fully closed, the retainer pins 56 and 58 hold the closure mating side 32 of the door 24 in its required position, close to the roof 18 and the end sill 20 for complete closure of the end 16 of the car body 12, and the door stiffening structure maintains a rigid and straight, or planar configuration of the door to resist an attempt by a would-be unauthorized entrant.
A similar stiffening structure is also provided on the opposite side door 22, as shown in
As shown best in
Each door engagement member 52, 54, 60, and 62 is spaced away from the door panel 40 to which it is connected by its location on the reinforcing hat shaped channel member 46, facilitating engaging the margin of the closure mating side of the opposite door as the doors 22 and 24 are moved to close them, but as shown in
On each of the doors 22 and 24, the respective ones of its pair of door engagement members 52, 54, or 60, 62 are separated by a distance 72, center-to-center, in the range of about one-fifth to about one-third of the total height of the door. The lower door engagement member 54 or 62 of each door may be spaced apart from the bottom of the respective door by a somewhat greater distance 76, in the range of about 35% to about 45% of the entire height of the door. Each of the upper ones of the door engagement members 52 and 60 may be separated from the top of the respective door by a distance 76 that may be in the range of about 35% to about 40% of the entire height of the door.
The engagement of the pins 56 with hooks at the roof 18, engagement of the pins 58 with hooks on the end sill of the car body, the stiffening structures including outer reinforcing plates 42 and inner reinforcing members 46, and the door engagement members 52, 54, 60, and 62 that prevent the margins of the closure mating sides 30 and 32 of the doors from being moved past each other, provide a stiffened door construction capable of successfully resisting nearly any attempt at unauthorized entry into such a railroad freight car 10.
The terms and expressions which have been employed in the foregoing specification are used therein as terms of description and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding equivalents of the features shown and described or portions thereof, it being recognized that the scope of the invention is defined and limited only by the claims which follow.
Number | Date | Country | |
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61794174 | Mar 2013 | US |