This invention disclosure generally relates to railroad car and, more specifically, to a system on a rail car for absorbing both buff and draft forces normally encountered by railcars during their in-service operation and a related method for absorbing energy on a railcar.
When a train consist is assembled in a rail yard, railcars run into and collide with each other to couple them to each other. Since “time is money”, the speed at which the railcars are coupled has significantly increased. Moreover, and because of their increased capacity, railcars are heavier than before. These two factors and others have resulted in increased damages to the railcars when they collide with each other and, frequently, the lading carried with such railcars.
As railroad car designers/builders continuing their efforts at reducing the weight of their designs, they have also identified a need and desire to protect the integrity of the railcar due to the excessive longitudinal loads/forces being placed thereon, especially as the railcars are coupled to each other. Whereas, such longitudinal loads/forces on the cars frequently exceed the design load limits set by the American Association of Railcars (“AAR”).
Providing an energy absorption system at opposed ends of each railcar has been long known in the art. In some applications, the energy absorption system at opposed ends of the ear is captured within a defined space provided between front and rear pairs of stops arranged in operable combination with a centersill at each end of the railcar. Also, and once installed into operable combination with a railcar, the energy absorption system at opposed ends of the railcar is expected to yield energy absorption capabilities for the railcar over an extended period of time which, depending upon the level of service wherein the railcar is employed, can last for many years if not decades. Such energy absorption systems can typically be classified into multiple groups. In one form, an energy absorption system can include a type of hydraulic dampener for reducing the energy directed against the railcar. Another form of energy absorption system uses steel springs for reducing the energy directed against the railcar. Yet another form a of energy absorption system utilizes a series of axially stacked elastomeric pads for absorbing and dampening the energy directed against the railcar. Still another type or form of energy absorption system utilizes a friction clutch assembly arranged in operable combination with axially stacked elastomeric pads for absorbing and dampening the energy directed against the railcar.
The impacts occurring during the “make-up” of a train consist and during in-service train action subject the energy absorption system at opposed ends of tine railcar to repeated buff impacts. In-service action also subjects the energy absorption system at opposed ends of the railcar to both repeated buff and draft events. The impacts associated with these events are transmitted from the couplers to the respective energy absorbing system or cushioning assembly and, ultimately, to the railcar body. That is, as the couplers are pushed and pilled in opposite longitudinal directions be it during in-service action and/or during the “make-up” of the train consist, such movements although muted by some degree by the cushioning assembly, are translated to the railcar body.
While use of a cushioning assembly in the form of a hydraulic dampener at opposed ends of the railcar offers certain advantages, such a cushioning assembly, however, is not without problems. Keeping in mind the service life of a railcar cushioning assembly can extend over several years, repeated longitudinal translations and reciprocations of an extended rod or member forming an essential part of the hydraulic dampener quickly and adversely wears on and, ultimately, destroys the sealing structure required with such a hydraulic dampener whereby minimizing its ability to provide railcar protection. Following continued use, a cushioning assembly in the form of a hydraulic dampener offers minimal draft protection. Moreover, and because of the design thereof, utilizing a cushioning assembly in the form of a hydraulic dampener furthermore requires use of a pair of center stops disposed proximately midway between the front stops and rear stops and arranged in operable combination with the centersill at both ends of the railcar. Also, the longitudinal distance between the front and rear pairs of stops on the centersill, wherein the hydraulics for such a cushioning assembly may be disposed, can be significantly greater than in other cushioning assembly arrangements.
A cushioning assembly which purely utilizes steel springs has many benefits. As will be appreciated by those skilled in the art, while serving to cushion the energy directed against such a cushioning assembly, use of steel springs in operable combination with a cushioning assembly offers little in the way of absorbing any of the energy directed against the cushioning assembly thereby returning that energy back through the train consist.
As mentioned, cushioning assemblies utilizing an axial stack of elastomeric pads to cushion the energy directed against the railcar are also known. Advantageously, and besides the benefits of cushioning the energy directed against the railcar, a cushioning assembly utilizing an axial stack of elastomeric pads furthermore yields the benefit of having at least a portion of the energy directed against the railcar being absorbed by the elastomeric pads. Unfortunately, and largely because of the both buff and draft directional forces being repeatedly applied to the cushioning assembly, such cushioning assemblies, especially when used in combination with today's railcars whereupon higher energy is being directed against them, have lesser degree of effectiveness to impact forces.
Because of the relatively high energy environment wherein such cushioning units are being used, a cushioning assembly which utilizes a friction clutch assembly arranged in operable combination with axially stacked elastomeric pads has proven very beneficial. These cushioning assemblies having a friction clutch arranged in operable combination therewith have been known to advantageously absorb high levels of energy imparted thereto. In some applications, such cushioning assemblies have advantageously been used in a tandem arrangement relative to each other to increase he level of energy which can be cushioned by such an arrangement.
These Applicants recognized and realized how particularly beneficial it could be if a purely mechanical energy absorption system could be used to replace the heretofore known cushioning assembly utilizing hydraulics. Such an energy absorption system can be beneficially used to cushion and absorb higher energy typically absorbed and cushioned by an energy absorption system utilizing hydraulics while eliminating the leakage problems known with such hydraulic systems.
Unfortunately, the pair of center stops required with a hydraulic cushioning assembly complicates simply switching a purely mechanical cushioning assembly for a hydraulic cushioning assembly. Applicants have found the pair of center stops required with a cushioning assembly using hydraulics structurally interferes with a design of a cushioning assembly utilizing other types of cushioning assemblies. The elongated space between the front and rear pairs of stops associated with a railcar which utilizes a cushioning assembly with a hydraulic unit presents other problems.
Simply removing the pair of center stops on the centersill to accommodate other types of cushioning assemblies has proven, for several reasons, particularly problematical. First, the expense involved with having to remove the pairs of center stops practically prohibits such an approach. Second, the pairs of center stops, inherently required to be used with any cushioning assembly utilizing hydraulics, are typically secured as by welding the center stops to the centersill of the railcar. As such, removal of the center stops, inherently required with any cushioning assembly utilizing hydraulics, requires cutting the pairs of stops from the centersill. As will be apparent to those skilled in the art, cutting both center stops from the centersill can considerably weaken the centersill of the railcar. Also, having to remove the pair of center stops from the sill to accommodate a cushioning assembly having a different design requires extensive time and efforts to effect such ends. For these and other reasons, simply replacing a cushioning assembly which utilizes hydraulics is far more complicated that it may initially appear.
It is also known to arrange a yoke in combination with the cushioning assembly. Typically, the yoke includes a back wall interconnected to top and bottom walls extending generally parallel to each other and toward an open end of the yoke. The cushioning assembly is typically sandwiched between the top and bottom walls of the yoke with a follower disposed toward a forward end of the cushioning assembly. The forward open end of the yoke is operably coupled to a railcar coupler which axially extends away from the cushioning assembly at each end of the railcar so as to allow adjacent railcars to be coupled to each other. Toward the open end thereof, the yoke is articulately connected to the railcar coupler through a suitable pin or key.
In buff events, a rear or butt end of a shank portion on the coupler moves axially inward and presses against the follower thus pushing the follower and cushioning assembly toward the pair of rear stops on the centersill. As the coupler and follower move under the influence of a buff event, a portion of the load or impact event is absorbed and dissipated by the cushioning assembly.
In draft events, unavoidable slack between adjacent but coupled railcars is taken up beginning at a starting or locomotive end of the train consist and ending at the other end of the train consist. As a result of the slack being progressively taken up, the speed difference between the railcars increases as the slack inherent with each railcar coupling at each end of the railcar in the train consist is taken up, with the resultant increase in draft events on the cushioning system. For example, when a locomotive on a train consist of railcars initially begins to move from a stopped or at rest position, there may be 100 inches of slack between the 50 or so pairs of couplings. This slack is taken up progressively by each pair of joined railcar couplings in the train consist. After the slack of the railcar coupling joining the last railcar to the remainder of the train consist is taken up, the next to the last railcar may be moving a few miles per hour. Given the above, it will be appreciated, the slack in the railcar couplers near the locomotive is taken up very rapidly while those railcars near the locomotive are subject to very high energy events being placed thereon. Such large energy events are capable of damaging railcar structures and sometimes the lading in the railcar.
Thus, there is a need and continuing desire for a railcar energy absorption system which is useful in both buff and draft directions to absorb and dissipate the relative high energies which are realized between coupled railcars throughout their operation.
In view of the above and in accordance with one aspect of this invention disclosure, there is provided an energy absorption system on a railcar having an axially elongated centersill with a pair of front stops and a pair of rear stops defining an elongated pocket therebetween. To facilitate use of known railcar structures, the energy absorption system of this invention disclosure is usable in combination with a railcar having a centersill with a pair of center stops disposed between the pair of front stops and the pair of rear stops. A coupler having a head portion and a shank portion is arranged in operable combination with the energy absorption system. The head portion of the coupler axially extends beyond an end of the centersill. In one embodiment, the energy absorption system includes a first cushioning assembly positioned in the pocket of said centersill between the pair of front stops and the pair of center stops. The first cushioning assembly includes a housing, a plunger arranged for axial sliding movements within an open end of said housing, and a resilient spring for consistently urging the plunger toward an extended position relative to the housing. A first follower is positioned in the pocket of the centersill and is normally urged toward and engageable with the front pair of stops under the influence of the spring of the first cushioning assembly. The first follower is operably engageable with a free end of the shank portion of the coupler.
According to the this aspect of the invention disclosure, the energy absorption system also includes a second cushioning assembly positioned in the pocket of the centersill to the rear of the first cushioning assembly between the pair of center stops and the pair of rear stops. The second cushioning assembly includes a housing, a clutch system arranged for axial sliding movements within an open end of the second cushioning assembly housing, and a resilient spring for consistently urging the plunger of the second cushioning assembly toward an extended position relative to the housing of the second cushioning assembly. A second follower is positioned in the pocket and normally urged toward and configured to engage with the center pair of stops under the influence of the spring of said second cushioning assembly.
Furthermore, the energy absorption system also includes an axially elongated yoke having a back wall engageable with a rear end of the second cushioning assembly along with top and bottom walls which extend forwardly from the back wall so as to encompass the first and second cushioning assemblies therebetween. The yoke terminates in an open forward end so as to allow the yoke to be coupled to the shank portion of the coupler.
With the present invention disclosure, the first and second cushioning assemblies act in series relative to each other to absorb and cushion impact forces directed against them when the energy absorption system operates in a buff direction. Advantageously, the second follower acts in concert with the pair of center stops and the second cushioning assembly to operably isolate the first cushioning assembly from draft events to minimize excessive draft travel and better dissipate rebound energy.
In one form, the first and second cushioning assemblies differ in their energy absorption capabilities. In one form, the second follower has a generally T-shaped configuration when viewed from a top thereof. A forward end of the second follower is preferably urged toward and engages a rear end of the housing of the first cushioning assembly. In a preferred embodiment, the housing of the first cushioning assembly is configured to fit laterally between the pair of center stops.
In a preferred embodiment, an operable overall thickness of the second follower can vary to allow the railcar energy system to be used in various railcars having different size pockets between the front pair of stops and the rear pair of stops. In one form, the energy absorption system of this invention disclosure has a combined travel in a buff direction of about 7.25 inches and a total travel in a draft direction of about 4.75 inches limited by the second cushioning assembly.
In one form, the housing of both the first cushioning assembly and the second cushioning assembly each have a closed end and an open end. In this embodiment, the yoke is movable relative to the housing of both the first cushioning assembly and the second cushioning assembly.
According to another aspect of this invention disclosure, there is provided a method for absorbing energy on a railcar having an axially elongated centersill with a pair of front stops and a pair of rear stops defining an elongated pocket therebetween. The centersill also has a pair of center stops disposed between the pair of front stops and the pair of rear stops. The railcar in which the present invention disclosure finds utility also has a coupler having a head portion and a shank portion. The head portion of the coupler axially extends beyond an end of the centersill. The method comprises the steps of: arranging an energy absorption system within the elongated. pocket defined between the first pair of front stops the pair of rear stops on the centersill. The energy absorption system includes a first cushioning assembly positioned in the pocket of the centersill between the pair of front stops and the pair of center stops. The first cushioning assembly includes a housing, a plunger arranged for axial sliding movements within an open end of the housing, and a resilient spring for consistently urging the plunger toward an extended position relative to the first cushioning assembly housing.
Another step in the method comprises: arranging a first follower in the pocket of the centersill such that the first follower is urged toward and engageable with the front pair of stops under the influence of the spring of the first cushioning assembly. The first follower is operably engageable with a free-end of the shank portion of the coupler.
According to this aspect of the invention disclosure, another step in the method comprises: configuring a second cushioning assembly to fit in the pocket of the centersill between the pair of center stops and the pair of rear stops. The second cushioning assembly includes a housing, a clutch arranged for axial sliding movements within an open end of the housing of the second cushioning assembly, and a resilient spring for consistently urging the clutch of the second cushioning assembly toward an extended position relative to the housing of the second cushioning assembly.
The method also comprises the step of: arranging a second follower in the pocket of the centersill such that the second follower is urged toward and is configured to engage with the center pair of stops under the influence of the spring of the second cushioning assembly.
The method further includes the step of: arranging an axially elongated yoke having a back wall along with top and bottom walls which extend forwardly from the back wall such that the top and bottom walls of the yoke entrap the first and second cushioning assemblies therebetween and terminate in an open forward end and is coupled to the shank portion of said coupler. The back wall of the yoke engages with a rear end of the second cushioning assembly when the coupler is pulled in draft.
According to this aspect of the invention disclosure, the first and second cushioning assemblies act in series relative to each other to absorb and cushion impact forces directed against them when the energy absorption system operates in a buff direction. When the energy absorption system operates in a draft direction, however, the second follower acts in concert with the pair of center stops and the second cushioning assembly to operably limit the run-out travel of the train consist while limiting the compression cycles of the energy absorption system in the draft direction to improve train handling.
In one embodiment, the energy absorption capabilities of the first and second cushioning assemblies differ. In a preferred embodiment, the method for absorbing energy on the railcar further includes the step of: configuring the second follower such that it has a generally T-shape when viewed from a top thereof In one form, the method for absorbing energy on the railcar can also include the step of: designing the second follower such that a forward end of the second follower engages an end of the housing of the first cushioning assembly after the first and second cushioning assemblies are arranged in operative cooperation relative to each other.
In one embodiment, the method for absorbing energy on a railcar can further include the step of: using various second followers having varying thicknesses to accommodate railcars having different size pockets between the front pair of stops and the rear pair of stops. The method for absorbing energy on a railcar preferably includes the further step of: configuring each housing of the first cushioning assembly and the second cushioning assembly with a closed end and an open end. Preferably, the method for absorbing energy on a railcar further comprises the step of: allowing the yoke to move relative to the housing of both the first cushioning assembly and the second cushioning assembly.
While this invention disclosure is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described preferred embodiments, with the understanding the present invention disclosure is to be considered as setting forth exemplifications of the disclosure which are not intended to limit the invention disclosure to the specific embodiments illustrated and described.
Referring now to the drawings, wherein like reference numerals indicate like parts throughout the several views, there is shown in
As shown in
The draft sill or centersill 14 shown by way of example in
In the embodiment illustrated by way of example in
The energy absorption system 40 is arranged in longitudinally disposed and operable combination with a standard coupler 50. The standard coupler 50 includes a head portion 52 and shank portion 54, preferably formed as a one-piece casting. As is typical, the coupler head portion 52 extends longitudinally outward from the centersill 14 to engage a similar coupler 50′ extending from an end of a second and adjacent railcar (not shown) to be releasably coupled or otherwise connected to car 10 (
The energy absorption system 40 of the present invention disclosure includes first and second cushioning assemblies 60 and 80, respectively, arranged. in generally axially aligned relation relative to each other and disposed in longitudinal and operable combination relative to each other. In. a preferred embodiment of this invention disclosure, the first cushioning assembly 60 is designed and configured to significantly reduce buff forces directed against it. In the one embodiment of the energy management system 40, the second cushioning assembly 80 has greater energy absorption capability than does the first cushioning assembly 60. As described below, the tandem cushioning assembly arrangement of this invention disclosure permits the first and second cushioning assemblies 60 and 80 to operate in series relative to each other in response to buff loads being imparted to system 40. Advantageously, however, the tandem cushioning assembly arrangement of the present invention is configured to allow cushioning assembly 80 to operably act to cushion and absorb the draft loads being imparted to system 40 during operation of the railcar 10 while substantially limiting run-out travel and minimizing cycles from draft events during operation of the railcar 10 (
The cushioning assembly 60 of each energy management system 40 is preferably positioned toward a forward end of the pocket 36 between the pair of forward stops 23 and the pair of center stops 27. The cushioning assembly 60 of each energy management system 40 initially receives and dissipates external buff forces experienced by the coupler 50; with such forces being transferred from the coupler head portion 52 to the butt end 54 of the coupler 50 during make-up of a train consist and in-service operations of such a train consist. As will be appreciated by those skilled in the art, the cushioning assembly 60 can take on any of a myriad of different designs and different operating characteristics without seriously departing or detracting from the true spirit and novel concept of this invention disclosure. In one form, the cushioning assembly 60 illustrated in the drawings can include a draft gear assembly of the type manufactured and sold by Miner Enterprises, Inc. under Model No, TP-17.
In the form illustrated by way of example in
Notably, as best shown in
Although available as an option, removing the center stops 27 from sill 14 to increase the size of such envelope or lateral space in the pocket 36 is cost prohibitive. That is, such option requires railcar 10 to be out of service for an extended time period while the pair of center stops 27 are removed. Also, removal of the pair of center stops 27 furthermore materially weakens the centersill 14. As such, acid in. a preferred embodiment of the present invention disclosure, the pair of center stops 27 remain an integral part of the sill 14. Instead, the first or rear end 63 of the housing 62 of the first cushioning assembly 60 is configured to be positioned in the narrowed space between the pair of upstanding center stops 27 on the centersill 14.
Returning to that embodiment illustrated by way of example in
As illustrated by way of example in
In the embodiment illustrated by way of example in
In a preferred embodiment illustrated by way of example in
In the embodiment illustrated by way of example in
In the embodiment illustrated by way of example in
In the illustrated embodiment, the front section 94 of follower 90 is configured to advantageously and slidably extend between the pair of center stops 27 on sill 14 whereby allowing the front face 91 of follower 90 to engage, impact and operate in combination with the rear end 63 of the first cushioning assembly housing 62 during operation of the energy absorption system 40. The rear face 92 of follower 90 is engaged by the distal or free end of the wedge 85 of the second cushioning assembly 80. When assembled in combination with and the second cushioning assembly 80 is in a “neutral” position (
Returning to
Turning to the embodiment illustrated by way of example in
As mentioned,
As shown in
Notably, as schematically illustrated in
As will be appreciated from an understanding of this invention disclosure, cushioning assembly 80 acts in series or concert with the first cushioning assembly to absorb, dissipate and return energy imparted to the system 40 during buff operations of railcar 10 (
Notably, when a buff impact of force is directed against the energy absorption system 40 of the present invention disclosure, yoke 100 also slides relative to the first and second cushioning assemblies 60 and 80, respectively, and to the right as seen in
Moreover, there is disclosed a method for absorbing energy on a railcar 10 having an axially elongated centersill 14 with a pair of front stops 23 and a pair of rear stops 25 defining an elongated pocket 36 therebetween. Centersill 14 also has a pair of center stops 27 disposed proximately midway between the front stops 23 and the rear stops 25. Railcar 10 also has a coupler 50 with a head portion 52 and a shank portion 54. The coupler head portion 52 axially extends beyond an end of the centersill 14 for allowing adjacent railcars to be interconnected to each other.
The method comprises the steps of: positioning a first cushioning assembly 60 in the centersill pocket 36 between the front stops 23 and the center stops 27. The first cushioning assembly 60 includes a housing 62, a plunger 64 arranged for axial sliding movements within an open end of the housing 62, and a resilient spring 66 for consistently urging the plunger 64 toward an extended position relative to the first cushioning assembly housing 62.
Another step in the method comprises: arranging a first follower 70 such that the first follower 70 is urged toward and engageable with the front stops 23 under the influence of the first cushioning assembly 60. The first follower 70 is operably engageable with a free-end of the coupler shank portion 54.
According to this aspect of the invention disclosure, another step in the method comprises: arranging a second cushioning assembly 80 in the centersill pocket 36 between he center stops 27 and the rear stops 25. The second cushioning assembly 80 includes a housing 82, a plunger 85 arranged for axial sliding movements within an open end of the second cushioning assembly housing 82, and a resilient spring 86 for consistently urging the second cushioning assembly plunger 85 toward an extended position relative to the second cushioning assembly housing 82. The method also comprises the step of: arranging a second follower 90 in the centersill pocket 36 such that the second follower 90 is urged toward and is configured to engage with the centerstops 27 under the influence of the second cushioning assembly.
The method further includes the step of: arranging an axially elongated yoke 100 having a back wall 102 along with top and bottom walls 104 and 106, respectively, which extend forwardly from the back wall 102 such that the top and bottom walls 104 and 106, respectively, of the yoke 100 entrap the first and second cushioning assemblies 60 and 80, respectively, therebetween and terminate in an open forward end and is coupled to and moves with the coupler shank portion 54. The back wall 102 of the yoke 100 engages with a rear end 83 of the second cushioning assembly 80 when the coupler 50 is pulled in draft.
According to this aspect of the invention disclosure, the first and second cushioning assemblies 60 and 80, respectively, act in series relative to each other to absorb and cushion energy directed against them when the energy absorption system 40 operates in a buff direction. Notably, with the present invention disclosure, only the second cushioning assembly 80 of each energy absorption system 40 operates in a draft direction. That is, the second follower 90 acts in concert with the pair of center stops 27 and the second cushioning assembly 80 to enhance or minimize draft energy realized during in-service train operations and thereby better control train actions.
Preferably, the method for absorbing energy on the railcar 10 comprises the further step of: configuring the first cushioning assemblies 60 to significant reduce buff forces directed against it. In one form, the second cushioning assembly has greater energy absorption capabilities than does the first cushioning assembly. In a preferred embodiment, the method for absorbing energy on the railcar 10 further includes the step of: configuring the second follower 90 such that it has a generally T-shape when viewed from a top thereof. In one form, the method for absorbing energy on the railcar 10 can also include the step of: designing the second follower 90 such that a forward end of the second follower 90 engages an end of the first cushioning assembly housing 62 after the first and second cushioning assemblies 60 and 80, respectively are arranged in operative cooperation relative to each other.
In one embodiment, the method for absorbing energy on a railcar 10 can further include the step of: using various second followers 90 having varying thicknesses to accommodate railcars having different size pockets between the front and rear stops 23 and 25, respectively. The method for absorbing energy on a railcar 10 preferably includes the further step of: configuring each housing 62 of the first cushioning assembly 60 and the housing 82 of the second cushioning assembly 80 with a closed end and an open end. Preferably, the method for absorbing energy on a railcar further comprises the step of: allowing the yoke 100 to move relative to the housing of both the first cushioning assembly 60 and the second cushioning assembly 80.
As will be appreciated from an understanding of this invention disclosure, the capability of the energy absorption system 40 to absorb, dissipate and return energy is dependent on any number of different factors. In one system, and with no changes to the design of the centersill 14 on car 10 or the existing position or provision of the front stops 23, the rear stops or center stops 27, the dual draft gear design of system 40 of the present invention disclosure allows it to consistently and repeatedly withstand, in buff, between about 120,000 to about 150,000 ft. lbs of energy being imparted thereto while not exceeding a maximum force level of about 700,000 lbs while the system 40 incurs travel of about 7.5 inches. In such system, and with no changes to the design of the centersill 14 on car 10 or the existing position or provision of the front stops 23, the rear stops or center stops 27, the dual draft gear design of system 40 of the present invention disclosure allows it to consistently and repeatedly withstand, in draft, between about 80,000 to about 90,000 ft. lbs of energy being imparted thereto while not exceeding a maximum force level of about 700,000 lbs while the system 40 incurs travel of about 4.5 inches. Of course, and as will be appreciated, other systems having different designs while incorporating the teachings and principals of this invention disclosure can embody different operating characteristics without detracting or departing from the spirit and scope of this invention disclosure.
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 scope of this invention disclosure. Moreover, it will be appreciated, the present disclosure is intended to set forth exemplifications which are not intended to limit the disclosure to the specific embodiments illustrated and described. 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.
This patent application relates to a co-pending and co-assigned U.S. PROVISIONAL patent application, namely U.S. patent application Ser. No. 62,1857,560 filed Jun. 5, 2019; the entirety of which is incorporated herein by reference.
Number | Date | Country | |
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62857560 | Jun 2019 | US |