Patent Application
20180305967
This invention relates to the field of railroad freight cars, and, in particular to railroad freight cars such as may employ bottom unloading doors.
There are many kinds of railroad cars for carrying particulate material, be it sand or gravel aggregate, plastic pellets, grains, ores, potash, coal or other granular materials. These materials are not liquid, yet may in some ways tend to flow in a somewhat liquid-like manner. Many of those cars have an upper opening, or accessway of some kind, by which the particulate is loaded, and a lower opening, accessway, or door, by which the particulate material exits the car under the influence of gravity. Clearly, while the inlet opening need not necessarily have a movable door (but may include a cover to discourage contamination of the lading or exposure of the lading to the wind, rain or snow), the outlet opening requires a governor of some kind that is movable between a closed position for retaining the lading while the lading is being transported, and an open position for releasing the lading at the destination. The terminology “flow through” or “flow through railroad car” or “center flow” car, or the like, may sometimes be used for cars of this nature where lading is introduced at the top, and flows out at the bottom.
Consider, for example, a hopper car for transporting sand or gravel aggregate. It may have a converging hopper discharge section that has the shape, generally speaking, of an inverted four sided, truncated pyramid. At the truncated bottom end, there may be a stationary plate and a moving plate, or door. When the moving plate and the stationary plate are brought together, the door is closed. The car is filled with lading, and is hauled to its destination. At the destination, the door or gate is opened, and the lading is allowed to escape from the hopper. The doors are driven by actuators connected to the doors by mechanical transmission elements.
In an aspect of the invention, there is a railroad hopper car having a hopper car body carried on railroad car trucks for rolling motion in a longitudinal direction. The railroad hopper car has a center sill. It also has a first hopper. The first hopper has a bottom discharge. The bottom discharge has a movable door mounted to govern egress of lading from the first hopper. The movable door being driven by a door actuator. The door actuator being located at the center sill. The door actuator is predominantly upstandingly oriented.
In a feature of that aspect of the invention, the door is a transverse door. In another feature, the railroad hopper car has first and second spaced apart sidewalls extending therealong. The first hopper has a first slope sheet extending obliquely upwardly away from the bottom discharge. The actuator is mounted in the lee of the first slope sheet. In another feature at least a portion of the actuator is mounted within the center sill. In another feature the actuator acts amidst the center sill. In still another feature, the actuator has a line of action that acts through the center sill. In a further feature, the center sill extends through the first hopper. In a still further feature, the door of the first hopper is split into first and second portions lying laterally to either side of the center sill. In another feature, the actuator is connected to the door by a mechanical transmission, and the mechanical transmission is bifurcated to drive the first and second portions. In another feature, the first and second portions are yoked to sweep through a common arc together. In another feature, the actuator is mounted on the car centerline.
In another aspect of the invention there is a railroad hopper car having a hopper car body supported by railroad car trucks for rolling motion in a longitudinal direction. The railroad hopper car has a center sill. It includes a first hopper, the first hopper having a bottom discharge. The bottom discharge has a movable door mounted to govern egress of lading from the first hopper. An actuator is connected to drive the movable door. The door actuator is predominantly upstandingly oriented. At least part of the door actuator being mounted within the center sill.
In a feature of that aspect of the invention, the center sill has a pair of spaced apart webs and a bottom flange. The bottom flange has a first portion having a first width adjacent the door, and a second portion having a second width adjacent the actuator. The first width is narrower than the second width. The door is mounted to swing beside the center sill alongside the first portion. The second portion has an aperture formed therein to permit the actuator to work therethrough. The actuator is connected to the door by a linkage that folds at least partially into the center sill. In another feature the actuator is connected to the door by mechanical linkages, and one of the linkages has a fulcrum mounted under the center sill. In a further feature, the actuator has a reaction mounted on top of the center sill. In another feature, the door is a transverse hopper door having first and second portions to either side of the center sill. In a further feature, the actuator is connected by a bifurcated linkage to drive the first and second portions of the door. In a still further feature, the first and second portions of the door are yoked to sweep together. In another feature, in a closed position of the door, the door has a free edge most distant from the actuator. The free edge has a backing beam extending thereacross. The backing beam yokes the first and second portions of the door together. The actuator is connected to the door by a mechanical transmission that includes a linkage mounted to the backing beam.
In another feature, the door is movable between an open position and a closed position. The actuator is connected to the door by linkages. The linkages are movable to an over center condition when the door is in the closed position. The linkages have a secondary lock operable to discourage movement out of the over-center condition when the actuator is passive.
In another aspect of the invention there is a secondary lock for a railroad hopper car door transmission, the secondary lock being mounted to body structure of the hopper car.
In a feature of that aspect of the invention, the secondary lock includes a base mounted to the body structure of the hopper car and a movable member that is biased toward engagement with the door transmission. The movable member has a first position in which it intercepts the door transmission, and a second position in which it is disengaged from the door transmission. In another feature, the movable member has a pawl operable to interact with a catch of the door transmission. In a further feature, the secondary lock includes a follower engagable with the door transmission, the follower being operable to release the secondary lock from the door transmission.
In still another feature there is a combination of the secondary lock and the door transmission more generally. The door transmission includes a catch, and the secondary lock includes a pawl. The pawl and the catch are mutually engaged when the door transmission is in a primary lock configuration. In another feature the secondary lock includes a follower and the door transmission includes a moving member. The moving member is operable in motion to engage the follower and thereby to release the secondary lock. In yet another feature the door transmission includes a sequencing member, and, when the sequencing member is moved, the secondary lock is released during a first portion of motion of the sequencing member. The transmission is released from a primary lock configuration during a second portion of motion of the sequencing member.
In another feature there is a linkage mounted to drive a door of a hopper, and an actuator mounted to drive the linkage. The linkage is drivable by the actuator to a primary lock configuration in which the linkage is in an over-center condition. There is a sequencing member, a catch, and a release member. The secondary lock is biased to engage the linkage. The secondary lock includes a pawl. The pawl is biased to engage the catch when the linkage is driven to the over-center condition. When so engaged, engagement of the pawl with the catch prevents the linkage from moving out of the over-center condition. The secondary lock includes a follower for engagement with the release member. The sequencing member is a lost motion fitting driven by the actuator. The actuator is operable to drive the lost motion fitting through a first portion of motion. During the first portion of motion the actuator also drives the release member in engagement with the follower to release the secondary lock. The actuator is operable to drive the lost motion fitting through a second portion of motion after the first portion of motion; and, during the second portion of motion the actuator also drives the linkage out of the over-center condition. In another feature, the sequencing member is mounted between the actuator and the linkages, whereby the actuator is operable to drive the linkage through the sequencing member. In still another feature, the lost motion fitting is an elongate slot in the sequencing member, and the release member is a cam that co-operates with the follower.
In another aspect of the invention there is a railroad hopper car door operating mechanism. It has an actuator, a primary lock, a secondary lock, a sequencing member, and a manual release operable when the actuator is inactive to release the secondary lock and the primary lock.
In a feature of that aspect, the manual release is operable to disengage the secondary lock prior to disengagement of the primary lock. In another feature, the manual release is mounted to the sequencing member. In another feature, the manual release member is movable. A first stationary member is mounted to the hopper car. The first stationary member functions as a fulcrum to permit a person standing at trackside to engage the release member with a lever, using the first stationary member as a fulcrum. In another feature, a second stationary member is mounted to the railcar. The second stationary member defines a lever guide by which a person standing at trackside may feed a first end of a lever to engage the manual release. In another feature the door operating mechanism includes a linkage mounted to drive a hopper door. The linkage is drivable to an over-center condition when the door is closed. The over-center condition defines the primary lock. The sequencing member is a lost motion member mounted between the actuator and the linkage. The linkage has a catch that is engaged by a pawl when the linkage is in the over-center condition, thereby preventing the linkage from moving out of the over-center condition, the catch and pawl defining the secondary lock. The lost motion member is movable when the manual release is driven first to release the secondary lock while taking up lost motion therein, and then to release the primary lock after lost motion therein is exhausted.
These and other aspects and features of the invention may be understood with reference to the description which follows, and with the aid of the illustrations of a number of examples.
The description is accompanied by a set of illustrative Figures in which:
The description that follows, and the embodiments described therein, are provided by way of illustration of an example, or examples, of particular embodiments of the principles, aspects or features of the present invention. These examples are provided for the purposes of explanation, and not of limitation, of those principles and of the invention. In the description, like parts are marked throughout the specification and the drawings with the same respective reference numerals. The drawings are not necessarily to scale and in some instances proportions may have been exaggerated in order more clearly to depict certain features of the invention.
The terminology used herein is thought to be consistent with the customary and ordinary meanings of those terms as they would be understood by a person of ordinary skill in the railroad industry in North America. Following from Phillips v. AWH Corp., the Applicant expressly excludes all interpretations that are inconsistent with this specification, and, in particular, expressly excludes any interpretation of the claims or the language used in this specification such as may be made in the USPTO, or in any other Patent Office, other than those interpretations for which express support can be demonstrated in this specification or in objective evidence of record in accordance with In re Lee, (for example, earlier publications by persons not employed by the USPTO or any other Patent Office), demonstrating how the terms are used and understood by persons of ordinary skill in the art, or by way of expert evidence of a person or persons of at least 10 years experience in the railroad industry in North America or in other former territories of the British Empire and Commonwealth.
In terms of general orientation and directional nomenclature, for railroad cars described herein the longitudinal direction is defined as being coincident with the rolling direction of the railroad car, or railroad car unit, when located on tangent (that is, straight) track. In the case of a railroad car having a center sill, the longitudinal direction is parallel to the center sill, and parallel to the top chords. Unless otherwise noted, vertical, or upward and downward, are terms that use top of rail, TOR, as a datum. In the context of the car as a whole, the term lateral, or laterally outboard, or transverse, or transversely outboard refer to a distance or orientation relative to the longitudinal centerline of the railroad car, or car unit, or of the centerline of a centerplate at a truck center. The term “longitudinally inboard”, or “longitudinally outboard” is a distance taken relative to a mid-span lateral section of the car, or car unit. Pitching motion is angular motion of a railcar unit about a horizontal axis perpendicular to the longitudinal direction. Yawing is angular motion about a vertical axis. Roll is angular motion about the longitudinal axis. Given that the railroad car described herein may tend to have both longitudinal and transverse axes of symmetry, a description of one half of the car may generally also be intended to describe the other half as well, allowing for differences between right hand and left hand parts. To the extent that this specification or the illustrations may refer to standards of the Association of American Railroads (AAR), such as to AAR plate sizes, those references are to be understood as at the earliest priority date to which this application is entitled.
By way of a general overview, car 20 may have a car body 22 that is carried on trucks 24 for rolling operation along railroad tracks. Car 20 may be a single unit car, or it may be a multi-unit car having two or more car body units, where the multiple car body units may be connected at an articulated connector, or by draw bars. Car body 22 may have a lading containment vessel or shell 26 such as may include an upstanding wall structure 28 which may have a pair of opposed first and second end walls 30, 32, that extend cross-wise, and a pair of first and second side walls 34, 36 that extend lengthwise. The end walls 30, 32 and side walls 34, 36 co-operate to define a generally rectangular form of peripheral wall structure 28. Wall structure 28 may include top chords 38 running along the top of the walls, and side sills 40 running fore-and-aft along lower portions the side sheets of side walls 34, 36. In some instances car 20 may have stub center sills at either end, in which case side walls 34, 36 may act as deep beams, and may carry vertical loads to main bolsters that extend laterally from the centerplates. Alternatively, or in addition to deep side beams, car 20 may include a center sill 42, which may be a straight-through center sill, running from one end of the car body to the other. In the case of a single, stand alone car unit, draft gear and releaseable couplers may be mounted at either end of the center sill. In a center flow, or flow through car, the upper portion of the car may typically include means by which to admit lading under a gravity drop system. Such an intake, or entryway, may be a large rectangular opening such as bounded by top chords 38, or the car may have one or more hatches, whether covered or uncovered.
The interior of car body 22 may include end slope sheets 44 and lateral partitions such as may be identified as intermediate slope sheets 46 that may extend between the sidewalls of the car, in a manner such as may tend to divide the internal space 48 of car body 22 into two or more sub-compartments, sub-volumes or subspaces indicated generally as 50, 52 and 54 in this example, and which may be referred to as first, second, and third hoppers. Clearly, in some embodiments there may be one single hopper, in others two hoppers and in others three, four, or more hoppers. The hoppers are bounded on their sides by side sheets 56 of side walls 34 and 36 that run between side sills 40 and top chords 38.
Car 20 may have relatively large slope sheets, be they 44 or 46, that extend cross-wise between sidewalls 34, 36, and which may tend to extend to a height relatively close to top chords 38. As may be noted, end sheets 44 may be slope sheets, and internal partition sheets 46 may also be slope sheets. Not atypically, each pair of fore-and aft opposed slope sheets, be they end sheets or internal partitions, may be inclined at equal and opposite angles, and the angles of those sheets may be selected to be somewhat steeper than the free slope angle, or natural talus slope angle, or angle of repose, of the lading for which the car is designed, such that, when the gates are opened, the lading may tend to flow out, rather than sit at rest. That is, taking either the coupler centerline height or the center sill cover plate upper surface as a datum, slope sheets 46 may terminate at a height that is at least half way to top chord 38, and which may, in some embodiments, extend more than ⅔, ¾ or ⅘ of that distance, as may be.
Car 20 may include a fitting mounted at the apex where two adjacent slope sheets 46 meet. It be termed a partition, or a divider, or reinforcement, and may be referred to as a ridge plate 58. Ridge plate 58 may include a central portion, and end portions mated to the side walls.
The lower regions of car body 22 may include gate or discharge assemblies 60, for the various hoppers, however many there may be, by which one or more members that are movable between closed and open positions may be used as a flow control to govern the egress of lading from that hopper. Discharge assemblies 60 may include the lower portion of, or a continuation of, one or both of the fore-and-aft slope sheets defining the fore and aft walls of that hopper. For example, hopper 50 (it being chosen arbitrarily, and generically) may include a first fore-and-aft hopper slope sheet extension 62, mounted to one slope sheet, e.g., item 44, and a second fore-and-aft slope sheet extension 64 mounted to an opposed slope sheet, e.g., be it item 46.
Discharge assemblies 60 may also include a pair of opposed inboard and outboard side sheet members, 66, 68. Side sheet members 66, 68 may be steel plates, and may be positioned to co-operate with slope sheet extension 62 to define a converging, or funnel-like passageway, or conduit, leading to a throat, or opening, indicated generally as 80, at which an exit, or port, or gate, however it may be termed, is defined. Each of hoppers 50, 52, 54 has a respective door or door assembly 70, 72, 74, each mounted at a respective pivot or hinge fitting 78. In the embodiment shown, all of these door assemblies are the same. Consequently only one such door will be described. It may also be noted that the presence of center sill 42 divides the opening into two portions, a first, or left-hand portion 102 lying to one side of center sill 42, and a second, or right-hand portion 104 lying to the other side of center sill 42. From one point of view, each corresponding door may therefore be considered as being a pair of two doors 112, 114; from another point of view each door may be considered to be a single door having two portions or halves, i.e., 112, 114. In a stub sill car, the opening could be uninterrupted, and could form a single continuous gate across the width of the car. Given that it is customary to discharge lading on both sides of the center sill at the same time to avoid asymmetric load distribution (as might tend to encourage the car to lean to one side, or tip), the right and left hand door portions are driven together. In the embodiments shown and described herein, the doors are yoked together by physical structure to compel them to sweep through the same arc at the same time. Accordingly, the choice of terminology of items 102, 104, 112 and 114 is somewhat arbitrary.
Looking at a single door portion, the sides of the periphery of any one left-hand or right-hand discharge opening 80 may be defined by the margins 82 of side sheet members 66 and 68 that angle upwardly and away from slope sheet extension 62. The bottom edge, or sill, of the discharge opening may be defined by the lowest margin or extremity of slope sheet extension 62, or such fittings or assemblies as may be mounted thereto. First slope sheet extension 62 may be a panel that is rigidly fixed relative to the first slope sheet, and may be made from a metal, such as a steel, that may serve as a wear plate, and which may be hardened or alloyed for such a purpose. Slope sheet extension 62 may be reinforced along its lower lateral margin by a lip stiffening member 86, which may be a U-pressing, or channel, mounted to the outside face of extension 62 and forming a hollow section therewith, capped by the wings, or tabs 76 of side sheet members 66, 68.
Slope sheet extension 64 may be a movable slope sheet extension, and may be, or may be part of, a moveable closure member or closure assembly 84 that is mounted to move between a closed position (
Where car 20 includes a straight through center sill, such as item 42, rather than having a single full width hopper discharge door assembly 90, such as might tend to be centered on the longitudinal centerline of the car, there may be two such discharge assemblies 90, one mounted to either side of center sill 42, in car 20. In this latter case, the center sill may tend to be protected from abrasion or other damage by one or more shrouds 88. Shroud 88 may, in cross-section, have the form of an inverted V, whose arms may extend on an incline upwardly from the upper, laterally inboard margin of inboard side sheet members 96, to meet at an apex above center sill 42 along the centerline of the car. In the illustrated embodiments, the closure assemblies include transverse doors. As suggested by the name, a transverse door extends cross-wise relative to the car body underframe, and the door motion is in a fore-and-aft swinging direction parallel to the center sill.
Door assembly 90 may include motion accommodating, or motion permitting, fittings, such as hinge 78. Hinge 78 may be received in a pivoting arm member, 94. Arm member 94 as may run along the back of the door pan sheet, or wing, defined by extension 64. Arm member 94 may extend generally radially away from hinge 78 toward the distal margin of extension 64, and may be a substantially planar member lying in a plane perpendicular to the axis of hinge 78. Given that hopper doors seem to be prone to abuse in service, extension sheet 64 may have a laterally extending reinforcement 96 that may run across the back of extension 64. Reinforcement 96 may have the general form of a flange or lateral reinforcement 98 running across the front lip of door assembly 90, bent to lie across the back of the webs defined by arm members 94, and inside edge reinforcement webs 92, thus forming an open box section, which, in effect, is a cross-wise extending beam. Once again, member 98 may provide a certain robustness of structure, such as may tend to discourage distortion of the distal margin of sheet 64 when the car moves with the door acting as something of a plow while the discharge section is still obstructed by the lading being discharged. Reinforcement member 98 may extend not only across the back of door assembly 90, but also across the back of the adjacent opposite handed door assembly 90 mounted on the opposite side of the car such that the two door assemblies may be yoked together, as shown in
The front or forward facing surface 108, or face of the panel, or pan defined by extension 64, may, in one context, be defined in terms of facing toward the interior of the hopper, or in a direction facing toward the lading, or toward the opposed members of the hopper discharge assembly in either the closed or the open position. The front, or upward, or inward facing surface 108, however, will tend, in general, to face inwardly toward the lading. Door assembly 90 may include upstanding lips, or cheeks, or legs, such as side wall members that stand proud of the inwardly facing surface of the door. The roots may lie directly over the mating webs of the gussets. When the mating moving and stationary portions of the discharge assembly come together, the edge members may tend to seat against the opposed lateral cheek, rim or lip, such as may be defined by a backing plate, or bar welded to one or the other of items 66, 68. The door assembly 90 is driveable between open and closed positions or conditions by an operating mechanism, indicated generally as 120. Operating mechanism 120 may include an actuator 122 and a mechanical transmission 124 linking the output of actuator 122 to door assembly 90. In one context, the actuator is a drive that operates the mechanical transmission. In another context the actuator can be considered part of the mechanical transmission as being an element of operating mechanism 120, more generally.
Considering
When the transmission is fully extended, the pivot points or pin connections 140, 144 and 146 are positioned in an over-center condition. That is to say, the force of gravity against door panel assembly 90, and particularly so if augmented by the weight of lading bearing on door panel assembly 90, may tend to want to drive lever 130 in the clockwise direction—i.e., the direction of closing, not of opening. It is prevented from further angular displacement in the clockwise direction by the over-travel range of motion limiting obstruction presented by the stop, or abutment, or dog, or catch, or pawl, or over-travel prevention pin or lug 150 that projects laterally from horn 148 of drag link 132. While the weight is on the door, pin 150 will bind against the upper margin of output arm 142. Drag link 132 can have a length adjustment, or length adjustor 152, which may typically be in the nature of a threaded rod and securement nut, which may be a wired or otherwise locked nut to prevent loosening. On assembly, adjustor 152 is set to fit the door to the door opening, with the over-travel lug in contact.
Fulcrum 140 is, or has, a pin joint formed at the apex of a fulcrum mounting fitting, or fulcrum stand, or fulcrum base, or footing 154. Base 154 has a foot or anchor or main mounting identified at flanges 156 that are rigidly attached to center sill 42. Footing 154 may have a generally triangular profile when seen in side view, and may have radial webs that extend along its edges to flanges at mounting 156 at which it is bolted to the flange, or flanges 158, of bottom cover plate 160 of center sill 42. As seen in the figures, the inboard face of footing 154, i.e., facing toward the centerline of the car, has stiffening ribs. In some contexts the entire structure may be referred to collectively as the fulcum.
Transmission 124 also has a secondary lock or secondary lock assembly, indicated generally as 162. It includes a suspended arm 164 that is pivotally mounted to the stationary structure of the car body underframe by a rigidly mounted bracket 168, in this case to bottom cover plate 160 of center sill 42. Suspended arm 164 may be biased toward engagement of transmission 124. It could be biased by gravity or other means. In the embodiment shown in
The distal end of arm 164 includes a pawl, abutment, catch, dog, lug, or pin 170. The back side of the elbow of input arm 138 has a corresponding seat, or catch, or notch 172 formed therein. When transmission 124 moves to the over center position, notch 172 will be presented to pawl 170, and, under the biasing influence of spring 166 as input arm 138 rotates clockwise pawl 170 will ride along the back face of the elbow of arm 138 until notch 172 is exposed and pawl 170 springs into place, thus capturing arm 138 and preventing return rotation in the counter-clockwise direction. Thus, even if car 20 should experience a vertical bounce that might otherwise tend to cause the over-center mechanism to jump and disengage, pawl 170 may tend to prevent such an occurrence from happening.
Indexing member 134 includes an information transmitting member in the form of a cam 174, and a lost motion element, identified as slot 176. The combination of items 174 and 176 permit indexing member 134 to function as a motion sequencing member, or information transmitting member that sets the order or schedule or sequence of steps of operation. That is, when actuator 122 operates to extend output shaft 128, the first portion of that motion takes up the slack in the linkage provided by slot 176. During the time period of this motion, cam 174 is delivering the message to secondary lock assembly 162 that it is time to permit release of pawl 170. Mechanism 120 delivers this message by causing cam 174 to bear against the near side of suspended arm 164, which acts as a cam follower. As this engagement occurs, spring 166 is compressed, and pawl 170 is disengaged from notch 172. By the time slot 176 reaches its end of travel on pin joint 136, pawl 170 is fully disengaged, and transmission 124 is ready for the next step in the sequence, namely the transmission of force and displacement from output shaft 128 to move pin joint 136, and therefore lever 130, in the counter-clockwise direction in
As best seen in the cross-sectional view of
In the sequence of
Placing actuator 122 in a substantially vertical orientation tends to permit the actuator installation to have a relatively short extent in the x-direction along the center sill. This, in turn, may permit two such actuators 122 to be mounted more closely together, and may permit transmission 124 to fold upward and to be generally more compact than might otherwise be the case. Where the installation is more compact, it tends to be possible for the space between adjacent hoppers to be smaller, such that the hopper discharge slope sheets can be closer together. “Closer together” can imply that the longitudinal size of the hopper discharge can be larger than before. If the discharge opening is larger, discharge may tend to be more rapid.
Vertical installation, or predominantly vertical installation, rather than horizontal installation along the inside of the center sill, may also tend to encourage use of shorter-stroke cylinders, such as may be smaller. While a single cylinder may be used to drive two longitudinally adjacent door sets at one time, the squat vertical installation may also tend to encourage the use of one actuator per door set, such that individual door pairs can be opened one-at-a-time. That is, each of hoppers 50, 52 and 54 can have its left and right hand doors controlled separately from the doors of the adjacent hopper, allowing partial discharge, separate discharge, or sequenced discharge.
The doors tend to require a high volume of air due to the cylinder size used. Using a squat, vertical cylinder in the center sill may tend to permit a reduction in the length of cylinder stroke required to open and close the doors. For cars with on-board reservoirs, in particular, using less air for each operation may tend to decrease the required frequency of refilling the reservoirs, and the time required to refill the reservoirs.
The shortening of the length of the center sill bottom cover plate flange deviations may tend also to permit the cover plate to return to its normal width abreast of each of the discharge doors. Effectively, this permits the inboard edge of each of the left-hand and right-hand doors to be located a few inches closer to the centerline of the car, thus increasing the effective door opening width. This is shown in
In
As described above there is a secondary lock assembly 162 mounted to body structure of hopper car 20. The movable member, arm 164, has a first position in which it intercepts the door transmission, and a second position in which it is disengaged from the door transmission. Pawl 170 is operable to interact with a catch, notch 172. In a further feature, the secondary lock includes a follower, the face of arm 164, that is biased to engage the cam defined by follower 174, and is operable to release secondary lock 162. The door transmission includes a sequencing member, namely extension 134, which is mounted between actuator 122 and the mechanical linkage of transmission 124. When extension 134 is moved, secondary lock 162 is released during a first portion of motion, as the lost motion of slot 176 is taken up. In this first portion of motion, neither force nor displacement is imparted to the over-center linkage. The transmission is released from a primary lock configuration, i.e., from the over-center condition, during a second portion of motion of the sequencing member after the lost motion has been exhausted. Actuator 122 then operates to drive the linkage through the sequencing member.
As described, secondary lock 162 stops the main lever from rotating without the cylinder being pressurized or activated. The “lost motion” (the amount of travel of shaft 128 before force is applied to the actuating lever) is provided in the clevis, i.e., extension 134, that attaches the cylinder rod, output shaft 128 to main lever 130. The clevis moves the secondary lock lever arm 164 clear of main lever 130 before applying force to the actuating lever when the cylinder is pressurized. The secondary lock lever is anchored to the car body. Alternatively, in other embodiments the secondary lock lever arm may be anchored to the cylinder body.
Mechanical transmission 124 has an actuator 122, a primary lock, a secondary lock, and a sequencing member, namely extension 134; and a manual release operable when actuator 122 is inactive, to release the secondary lock and the primary lock. The manual release is operable to disengage the secondary lock prior to disengagement of the primary lock. The manual release, namely prying lug 242, is mounted to extension 134. Being part of mechanical transmission 124, the manual release member is movable, while fulcrum 244 is mounted to the stationary, or datum, structure of the underframe of hopper car 20. This permits a person standing at trackside to engage the release member with a lever using the stationary member as a fulcrum. A second stationary member, namely wing 238 is mounted to car 20, thereby defining a lever guide by which to feed a first end of a lever or pry rod to engage the manual release. The mechanism is designed such that the door may be opened manually if a source of pressurized air is not available. In other mechanisms, a first action must be taken to release the secondary locking prior to a second action of rotating the main lever. The new design has both actions performed by a single operator input. A pry bar moves the cylinder clevis such that the secondary lock is disengaged and the main lever is rotated with a single motion. This provides a means of opening the door in the event that no pneumatic supply is available.
The assembly described above may also be used, whether by retrofit or otherwise, with cars having left and right hand doors with split force inputs, as shown in
The mechanisms described above are for the operation of bottom discharge doors on railroad hopper cars, whether covered or open top. Each mechanism uses a single cylinder for each pair of doors (i.e., a left-hand door, and a right hand door, yoked together). Each cylindrical actuator is oriented in a near vertical position or a position such that it does not extend between the doors, causing the area of the doors to be reduced, i.e., because the center sill flanges would otherwise have to extend to a greater width). The cylinder orientation is such that it protrudes up through the center sill. The cylinder 126 is connected to one end of a lever 130 that is located at the center line of the car. The lever fulcrum 140 is at a location below center sill 42 and is connected to support-brackets, namely of mounting base 154, that are suspended from center sill 42. The end of the lever opposite the cylinder, i.e., output arm 142, is connected to a linkage member 132. Linkage member 132 is connected to door assembly 90. Door assembly 90 has a pair of transverse doors 112, 114 on opposite sides of center sill 42. The doors are connected by a rigid beam such that the doors operate in unison. The linkage member connects at the center point of the rigid beam, as seen in
In another iteration of the new design, a different method was used to connect the lever to the door. The linkage that connects to the door was generally triangular, which provided two locations for two eye bolts to connect to the door assembly. While this design was found to be heavier than the single connection, it may be used on cars already built with doors that accommodate two points of connection to the mechanism. The mechanism operates in a manner such that when in the closed position, the lever and linkage members lock the door by resting in an over-toggle position. This over-toggle position (shown in
The cylinder is locked by way of a secondary locking mechanism in addition to the main lever locking in over-toggle position. This mechanism uses a small locking lever that holds the main lever in the closed position until the cylinder is actuated. Lost motion in the cylinder moves the locking lever such that it disengages from the main lever prior to applying any force to the main lever. Once the locking lever is clear of the main lever, it is free to rotate in response to the cylinder applying force.
As described above, the apparatus has a substantially linear single actuating lever 130 that connects to the cylinder, i.e., actuator 122, at one end, a door linkage 132 at the other end and pivots about a central fulcrum 140. Lever 130 is approximately horizontal when reacting the forces on the door. In other embodiments, lever 130 may be at some angle other than horizontal. Lever 130 may itself form an angle, or dog leg, or curve, such that the cylinder and door linkage connection points are at less than 180 degrees from one another (could be at 90 degrees, or L shaped for example).
The apparatus described above has a cylinder (i.e., actuator 122) that extends predominantly upward from the mechanism of mechanical transmission 124 such that it is substantially out of the plane of bottom cover 160 of center sill 42. This allows the profile of the center sill to be narrower at the location of the doors, and allows the door openings to be larger. The cylinder extends up through the top cover plate 186 of center sill 42. In an alternate embodiment, the angle of the cylinder may be slightly less vertical in order to decrease the height of the top cylinder hinge point at pin 178, removing the need for an opening in the center sill top cover. That is, the mounting for pin 178 can be on the underside of cover plate 186, rather than above it. In another alternative embodiment, in the case of a car with no center sill (a stub sill design), the cylinder is oriented in a way that it does not interfere with the motion of the door or required a reduction in the door size. In this case, rather than two side-by-side door openings, there may be one continuous door that extends laterally across the car.
In each of the embodiments described the transmission includes a linkage, or assembly of linkages that connect to the door assembly at a center location, i.e., along the centerline of car 20. The connection to the door is near the bottom, or distal, edge of the door. The door connections may also be a plurality of connections that may be laterally away from the center of the door assembly. In some embodiments the linkage may connect to the door at some different location with respect to the distance from the bottom edge of the door, i.e., not quite as close to the distal margin.
Various embodiments have been described in detail. Since changes in and or additions to the above-described examples may be made without departing from the nature, spirit or scope of the invention, the invention is not to be limited to those details.
