Patent Application
20120210906
This invention disclosure generally relates to railroad hopper cars and, more specifically, to an apparatus for controlling discharge of material from a railroad hopper car.
One type of railroad freight car in use today is an open-top hopper car wherein an elongated walled enclosure or hopper holds material there within. The hopper is mounted on a mobile frame or undercarriage and defines a longitudinal axis for the car. Such railcars are used to transport aggregate, iron ore, coal and other materials and offer an advantageous economical method of transporting large amounts of materials between distant locations.
The granular commodities or materials can be rapidly discharged from the hopper through a discharge opening defined by the hopper. In many open-top railroad hopper cars, one or more doors are pivotally mounted or hinged along an upper edge to the hopper for vertical swinging movement between closed and open positions relative to the discharge opening. When closed, the doors prevent discharge of materials from the hopper. When released from their closed position, the doors gravitationally swing toward an open position assisted by the material moving through the discharge opening.
As will be appreciated, different door operating devices have been proposed to releasably maintain the doors in their closed position. It is important to note, however, such door operating devices are specifically designed to the particular application with which they will find use. For example, a device used to operate longitudinally mounted swinging doors on a railroad hopper car cannot, without substantial modifications and redesign, be used to operate transversely mounted doors on a railroad hopper car. Conversely, and primarily because of the disposition of the doors on the railroad hopper car, known devices used to operate transversely mounted swinging doors on a railroad hopper car cannot, without substantial modifications and redesign, be used to operate longitudinally mounted swinging doors on a railroad hopper car.
Designing an apparatus used to control operation of the doors of an open-top railroad hopper car used to transport ore, coal and like materials, is complicated by the relatively heavy weight of the materials. That is, the weight of the materials carried in the railcar hopper impart a significant columnar load to the doors in the closed position. Moreover, and once the doors are released from their closed position, the gravitationally falling material tends to force the doors open with significant force. As such, the mechanism used to control operation of the doors must have sufficient strength and rigidity to perform under conditions wherein significant loads and forces are imparted thereto during all phases of door operation.
Once a hopper car reaches an unloading site, the doors on the hopper are swung open and gravity normally causes the material within the hopper to flow therefrom. As mentioned, however, the materials within the hopper exert a relatively large columnar load on the doors. Such downward load on the door has caused and continues to cause a significant problem in manual opening of the doors at the unloading site. Of course, at the unloading site time is of the essence and any complications involving opening of the doors to unload the material from the hopper prevents serious concerns:
In some applications, mechanized openers are used to operate the railroad hopper car doors. These mechanically driven openers include a rotatably driven member which must be aligned with and engage a free end of an operating shaft forming part of the door operating mechanism. As such, and unless the opener is timely removed from engagement with the operating shaft of the door operating mechanism, and as the doors swing to their open position, the significant loads acting on the doors by the gravitationally falling materials moving through the discharge opening can be transferred to the driven member of the opener. Besides the problems involved with properly aligning the driven member of the opener to the operating shaft of the door operating mechanism, these transferred loads can and often do result in significant damage to the opener. Moreover, and as the railcar moves along the rails during the unloading process, the mechanically driven opener is dragged along therewith, thus, imparting other loads and forces to the apparatus used to control operation of the doors.
Because some railcar hoppers are of an open-top design, the material in the hopper car is continually exposed to the environment and weather conditions. In cold weather environments, the particulate material in the open-top hopper frequently freezes together thus hindering their discharge from the railcar hopper. Such conditions often require workers at the discharge sites to strike the sides of the railcar hopper with large hammers in an effort to loosen the frozen materials and create a flow of material through the discharge opening. As will be appreciated, and besides the adverse time consuming affects resulting from such needed manual efforts, striking the hopper with a large hammer can also result in significant damage to the railcar.
Thus, there is a need and continuing desire for an apparatus for controlling the positive discharge of materials from a railroad car having an open-top hopper notwithstanding the environment while facilitating use of and offering protection to a driven opener used to open the doors of a railroad hopper car.
In view of the above, and in accordance with one aspect, there is provided an apparatus for controlling the discharge of materials from a railcar having a wheeled frame defining a longitudinal axis for the car and a hopper carried on the frame. The hopper defines a longitudinally disposed discharge opening. The railcar has a door mounted to the hopper for pivotal movement between an open position and a closed position relative to the discharge opening. The apparatus for controlling the discharge of materials from the railcar includes an rotatable operating shaft and a drive operably coupled between the door and the operating shaft for causing the door to move from the closed position toward the open position in response to rotation of the operating shaft. The drive also includes a lost motion connection for allowing the door to freely pivot toward the open position during collapsing movement of the lost motion connection and after the operating shaft has been rotated a predetermined amount to open the door. The lost motion connection protects the operating shaft against the gravitational effects the materials have acting on the door as the door moves toward the open position.
Preferably, the apparatus for controlling the discharge of materials from the railcar further includes a bumper for cushioning impacts of the free falling door against the frame when the door freely pivots toward the open position. In one form, the bumper is formed from elastomeric material.
In one embodiment, the drive for operating the door has a linkage assembly including first and second interconnected links positioned relative to each other, when the door is in the closed position, in an overcenter relationship whereby allowing the links to act as a primary lock for releasably maintaining the door in the closed position while preventing the door from inadvertently moving toward the open position. The drive furthermore preferably includes a gear box for transferring rotating movement of the operating shaft to the linkage system. The gear box preferably includes a worm gear rotatable with the operating shaft and a driven gear arranged in operable combination with the worm gear. The worm gear and driven gear serve as a secondary lock for releasably maintaining the door in the closed position.
In one form, the lost motion connection includes a slotted drive member which permits the drive to freely move through a predetermined range of movement and relative to the operating shaft before the door begins to move toward the open position. Preferably, the slotted drive member of the lost motion connection includes radially spaced pin engaging surfaces. In one form, the lost motion connection further includes a pin arranged for movement between the pin engaging surfaces of the slotted drive member for reconnecting the operating shaft with the drive upon the collapse of the rotary lost motion connection. In one form, the pin associated with the lost motion connection is preferably configured as a shear pin so as to advantageously offer protection to the each drive against an overload of torque being applied thereto.
According to another aspect, there is provided an apparatus for controlling discharge of materials from a railcar having a wheeled frame defining a longitudinal axis for the car and a hopper carried on the frame. The hopper defines a longitudinally disposed discharge opening. The railcar has a door mounted to the hopper for pivotal movement between an open position and a closed position relative to the discharge opening. The apparatus for controlling discharge of materials from a railcar includes an operating shaft carried by the car for rotation about a fixed axis and a drive operably coupled between the door and the operating shaft for causing the door to move from the closed position toward the open position in response to rotation of the input shaft. The drive includes a driven shaft carried by the car in generally normal relation relative to the operating shaft. The driven shaft is operably coupled to the operating shaft such that when the operating shaft is rotated the driven shaft rotates therewith. The drive further includes a lost motion connection between the door and the operating shaft for isolating the operating shaft during collapsing movement of the lost motion connection from the gravitational forces of material acting on the door as the door moves toward the open position.
Preferably, the drive includes a shear key operably disposed between the operating shaft and the door for inhibiting damage to the drive during operation of the door. In one form, a bumper is provided for cushioning impacts of the door against the frame when the door freely pivots toward the open position. The bumper preferably includes elastomeric material.
In one form, the drive has a linkage assembly including first and second interconnected links positioned relative to each other, when the door is in the closed position, in an overcenter relationship whereby allowing the links to act as a primary lock for releasably maintaining the door in the closed position while preventing the door from inadvertently moving toward the open position. Preferably, the drive further includes a gear box for transferring rotating movement of the operating shaft to the linkage assembly. In one form, the gear box includes a worm gear rotatable with the operating shaft and a driven gear arranged in operable combination with the worm gear. The worm gear and the driven gear serve as a secondary lock for releasably maintaining the door in the closed position.
The lost motion connection furthermore preferably includes a slotted drive member which permits the drive to freely move through a predetermined range of movement before the door begins to move toward the open position. In one form, the slotted drive member of the rotary lost motion connection includes radially spaced pin engagement surfaces. In one embodiment, the lost motion connection further includes a pin carried by said driven shaft and arranged for movement between the pin engagement surfaces for reestablishing the connection between the operating shaft and drive upon the collapse of the rotary lost motion connection.
According to another aspect, there is provided an apparatus for controlling discharge of materials from a railcar having a wheeled frame defining a longitudinal axis for the car and a hopper carried on the frame. The hopper defines a longitudinally disposed discharge opening. The railcar has two doors mounted to the hopper for pivotal movement between an open position and a closed position relative to the discharge opening. A first door is mounted to one lateral side of the longitudinal axis of the car while a second door is mounted to an opposed lateral side of the longitudinal axis of the car. The control apparatus includes an elongated operating shaft carried by the car for rotation about a fixed axis and which moves the first and second doors simultaneously from the closed position toward an open position. Opposed ends of the operating shaft are accessible from opposed sides of the car. First and second drives are operably coupled between the first and second doors and the operating shaft for causing the doors to move from the closed position toward the open position in response to rotation of the operating shaft in a first rotational direction. Each drive includes a lost motion connection for allowing the respective door to freely pivot toward the open position during collapsing movement of the lost motion connection and after the operating shaft has been rotated a predetermined amount to open the doors. The lost motion connection of each drive isolates the operating shaft during collapsing movement of the lost motion connection against the gravitational forces of material acting on the doors as the doors move from the closed position toward the open position.
In a preferred form, both the first drive and the second drive include a shear member operably disposed between the operating shaft and the first and second doors for inhibiting damage to either drive during operation of the doors. Moreover, each drive preferably includes a bumper for cushioning impacts of the first and second doors against the frame when the doors freely pivot toward their open position. In one form, each bumper includes elastomeric material.
Preferably, the first drive and the second drive each include a linkage assembly including first and second interconnected links positioned relative to each other, when the respective door is in the closed position, in an overcenter relationship whereby allowing the links to act as a primary lock for releasably maintaining the respective door in the closed position while preventing the respective door from inadvertently moving toward the open position.
Additionally, each drive preferably includes a gear box for transferring rotary movement of the operating shaft to the linkage assembly of the respective drive. In a preferred form, the gear box of each drive includes a worm gear rotatable with the operating shaft and a driven gear arranged in operable combination with the worm gear. The worm gear and driven gear serve as a secondary lock for releasably maintaining the respective door in the closed position.
In one embodiment, the lost motion connection of each drive includes a slotted drive member which permits the drive to freely move through a predetermined range of movement relative to the operating shaft after the respective doors move toward the open position. In one form, the slotted drive member of the rotary lost motion connection includes radially spaced pin engaging surfaces. In one embodiment, the lost motion connection further includes a pin carried by the driven shaft and arranged for movement between the pin engaging surfaces for reestablishing the connection between the operating shaft and drive upon the collapse of the rotary lost motion connection: Moreover, each drive preferably includes a mechanical indicator for visually indicating the position of the respective door relative to the closed position.
While this invention disclosure is susceptible of embodiment in multiple forms, there is shown in the drawings and will hereinafter be described a preferred embodiment, with the understanding the present disclosure sets forth an exemplification of the disclosure which is not intended to limit the disclosure to the specific embodiment illustrated and described.
Referring now to the drawings, wherein like reference numerals indicate like parts throughout the several views, there is shown in
In the embodiment illustrated in
The flow or discharge of material from hopper 12 through discharge opening 30 is controlled by first and second longitudinally elongated doors 40 and 50 mounted to the hopper 12 for pivotal movements between a closed position (
Operation of the doors 40, 50 is controlled by an apparatus generally designated in
Because there are two doors 40 and 50 associated with hopper 12, and as shown in
Each drive 70 and 70′ preferably and advantageously serves identical and multiple purposes. That is, each drive is operably coupled between the respective door and the operating shaft 62 for controlling movement of the respective door between the closed position and the open position in response to rotation of the operating shaft 62 in a first direction about axis 64. Each drive furthermore preferably serves to maintain and releasably hold the respective door in the closed position. Moreover, each drive is preferably configured to provide a visual indication of the position of the respective door relative to the discharge opening 30.
In the form shown by way of example in
As shown in
As shown in
Turning now to
In the form shown in
As shown in
In the embodiment illustrated by way of example in
As shown in
In a preferred embodiment, each linkage assembly 90 and 90′ is preferably designed as an overcenter linkage mechanism and acts as a primary lock for the respective door operated thereby. That is, when the respective door is in a closed position, the location 106 wherein arm 98 of link 92 is articulately interconnected to link 94, along with the location 126 of the articulate connection of link 94 relative to the respective door 40 and relative to axis 86 of shaft 85 are such that an overcenter relationship or design is preferably established when the respective door is in the closed position. Preferably, when door 40 is in the closed position, the location 106 of the connection between arm 98 of link 92 and link 94 assumes an overcenter position relative to the axis 86 of shaft 85 and the location whereat link 94 is connected to the respective door 40 to positively maintain the respective door in the closed position. As such, the location 106 of the connection between arm 98 of link 92 and link 94 is required to move overcenter when the door is to be moved from the closed position toward the open position. Preferably designing each drive 70, 70′ with such overcenter capability allows the linkage assembly 90, 90′ of each drive 70, 70′ to operably serve as a primary kick for releasably maintaining the respective doors 40, 50 in their closed position.
In the embodiment illustrated by way of example in
Each drive 70, 70′ of the control apparatus 60 further includes a gear box 130 fixedly mounted-on frame 24 of car 10 and which receives rotational input from operating shaft 62. Amongst other features, the gear box 131 serves a s a torque multiplier between operating shaft 62 and shaft 75. In the embodiment illustrated by way of example in
In a preferred embodiment, drive gear 132 is configured as a worm gear. To open the door with which gear box 130 is associated requires worm gear 132 to be driven in one rotational direction. Notably, the forces acting on the respective door cannot drive the worm gear in reverse - in a direction opposed to that direction for opening the door. As such, and in combination with the intermeshing relationship with driven wheel 134, permits gear box 130 to act as a secondary lock for releasably maintaining each door 40, 50 in the closed position while preventing the door from inadvertently moving toward the open position.
Once the doors 40 and 50 are released from the their locked and closed position (
To achieve such advantageous ends, each drive 70. 70′ of control apparatus 60 includes a lost motion connection 140 operably disposed between the doors 40, 50 and the operating shaft 62 for allowing a predetermined range of free movement of each drive 70, 70′ once the doors 40, 50 begin their movement toward the open position. In the embodiment illustrated in
As shown in
When the doors are in their releasably closed position, the drive pin 144 of each lost motion connection 140 is in the position illustrated by way of example in
As the sleeve 142 of the lost motion connection 140 is rotated in a counterclockwise direction as shown in
In a preferred form, link 92 is required to rotate in a counterclockwise direction as shown in
Once the overcenter locking arrangement of linkages 90 and 90′ is overcome, the drive pin 144 freely moves or traverses from the position shown in
Because the drive pin 144 is permitted to freely move or traverse through the circumferential slots 149 and 149′ during collapse of the lost motion connection 140, shaft 75 freely moves relative to the operating shaft 62 whereby substantially removing the forces which would otherwise be imparted to the operating shaft 62 as a result of the gravitational effects the materials being discharged from the hopper 12 have acting on the doors 40, 50 as the door moves toward their open position relative to the discharge opening (
In the preferred embodiment, movement of link 92 in a counterclockwise direction as shown in
In a preferred form, and because of the relatively high level of impact the freely falling doors 40 import to the hopper 12 and frame 24, at least one cushioning apparatus 150 (
Returning to
In the embodiment illustrated in
To return the doors 40, 50 toward and into a closed position (
As the sleeve 142 of the lost motion connection 140 is rotated in a clockwise direction as shown in
In a preferred form, rotation of link 92 in a clockwise direction as shown in
Returning to
Providing an input shaft 170 as part of each drive 70 and 70′ serves a number of advantageous ends. First, providing shaft 170 as part of each drive 70 and 70′ and part of control apparatus 60 standardizes the location and size of the operating shaft 62 relative to current railroad hopper cars. Second, providing shaft 170 as part of each drive 70 and 70′ and as part of control apparatus 60 advantageously isolates lateral, vertical, torsional and impact forces being imparted to the control apparatus 60 during operation of the doors 40 and 50 by either the conventional driver, used to move the doors between open and closed positions, or movements of the railcar during the unloading process. These and other advantageous ends, apparent to those skilled in the art, will be appreciated from the following disclosure.
Turning to
In the embodiment illustrated by way of example in
As will be appreciated by those skilled in the art, any of several unexpected occurrences can inadvertently occur during operation of the hopper car. For example, as a result of rocks, and related debris becoming inadvertently entangled with ether drive 70, 70′ the doors 40, 50 may be incapable of being moved under the influence of the continuously rotating conventional driver (not shown). Another example which could potentially cause damage to the control apparatus 60 can include a situation where the conventional driver continuously rotates after the doors 40, 50 are moved to either of their extreme positions thus exposing the control mechanism 60 to an excessive amount of torque being applied to the control apparatus 60 by the continuously rotating spindle of the conventional driver or the control limits on the conventional driver being set too high.
As such, drive transfer mechanism 176 furthermore preferably includes a shear pin 190 for protecting each drive 70, 70′ and control apparatus 60 against inadvertent damage. Upon the happening of any one or more of the above-mentioned unexpected occurrences and others, the shear pin 190 will shear or otherwise break thereby separating the input shaft 172 from the control apparatus 60 so as to protect and isolate the control apparatus 60 against serious damages.
From the foregoing, it will be observed that numerous modifications and variations can be made and effected without departing or detracting from the true spirit and novel concept of this invention disclosure. Moreover, it will be appreciated, the present disclosure is intended to set forth an exemplification which is not intended to limit the disclosure to the specific embodiment illustrated. Rather, this disclosure is intended to cover by the appended claims all such modifications and variations as fall within the spirit and scope of the claims.
