Patent Publication Number: US-2022212643-A1

Title: Systems and method for securement of a container to a vehicle having a brake system

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This patent application incorporates by reference co-owned U.S. Pat. Nos. 9,387,792, 9,463,732, and 9,802,526, each entitled “Latching System for Automatic Securement of a Container to a Container Chassis” by John J. Lanigan, Sr., et al., co-owned U.S. Pat. No. 9,340,146, entitled “Front Pin Latching System for Automatic Securement of a Container to a Container Chassis” by John J. Lanigan, Sr., et al., and co-owned U.S. patent application Ser. No. ______, entitled “Latching Device and Method for Automatic Securement of a Container to a Container Chassis” by James T. Russo et al. 
    
    
     BACKGROUND OF THE DISCLOSURE 
     1. Field of the Disclosure 
     The present subject matter relates generally to securement systems and methods, and more particularly, to systems and methods for securement of a container to a vehicle having a brake system. 
     2. Description of the Background of the Disclosure 
     In a conventional container chassis used for transporting a container, the container is secured to the container chassis by two latches spaced apart at each of the two front corners and two latches spaced apart at each of the two rear corners of the container chassis. In one design these latches are manually operated by the driver or other personnel. The rear latches may have a twist lock that is inserted into the bottom of the corner castings of a container. The twist lock may be operated by a lever to move the twist lock between an unlatched position and a latched position. The front latches of a conventional chassis that is 40 to 53 feet in length may have locking pins that extend horizontally into openings of the corner castings of the container. The front of a conventional chassis that is 20 feet in length may utilize a twist lock and manual lever rather than the locking pins. 
     Such conventional latching devices are manually operated by the chassis driver or other personnel when a container is placed on a chassis. Subsequently, the conventional latching devices are manually unlocked before the container is removed from the chassis. In this regard, the driver or other personnel may improperly or incompletely lock or unlock the latching devices, which may cause improper loading/unloading of the container to/from the chassis and/or create the potential for shifting of or losing a container during road transport. 
     In the railway transportation industry, a container is typically secured to the four corners of a railcar using a swing-type latch. Two swing-type latches spaced apart at each of the two front corners and two swing-type latches spaced apart at each of the two rear corners of the railcar secure the container thereto. Similar to the twist lock latch of a container chassis, the swing-type latches of the railcar enter openings along the bottom surface of each corner casting of the container. Unlike the twist lock latch, the swing-type latch is continuously biased into position by a spring. As the container is placed on the railcar, the latch is pushed back against the spring until the latch clears the bottom surface of the corner casting. The latch is designed such that a significant force must be applied against the latch to remove the container from the railcar. A container weight of approximately 700 lbs. may be required to load the container onto the railcar, and a force of approximately 2,000 lbs., for example, may be necessary to remove the container from the railcar. 
     Co-owned U.S. Pat. No. 9,340,146 incorporated by reference herein discloses a front pin latching system for automatic securement of a container to a container chassis. The front pin latching system includes a shelf configured to move vertically on an outer surface of the container chassis. The shelf and the container chassis have adjacent openings. The system also includes a pin configured to move horizontally through the adjacent openings and a linkage mechanism disposed on an inner surface of the container chassis. The linkage mechanism is operably coupled to the shelf and the pin. Placement of the container on the container chassis moves the shelf causing the linkage mechanism to move the pin such that the pin automatically secures the container to the container chassis. 
     Co-owned U.S. Pat. No. 9,387,792 incorporated by reference herein discloses a latching system for automatic securement of a container to a container chassis. The latching system includes an actuation device disposed on an upper surface of the container chassis, a linkage mechanism disposed below the upper surface, and a connector positioned on a further surface elevated above the upper surface. Placement of the container on the container chassis actuates the actuation device causing the linkage mechanism to move the connector and automatically secure the container to the container chassis. 
     Co-owned U.S. Pat. No. 9,463,732 incorporated by reference herein discloses a latching system for automatic securement of a container to a container chassis. The latching system includes an actuation device that extends through a surface of the container chassis, a linkage mechanism disposed below the surface, and a latch coupled to a pivot. The latch is positioned above the surface of the container chassis. Placement of the container on the container chassis actuates the actuation device causing the linkage mechanism to move the latch such that the latch automatically secures the container to the container chassis. 
     SUMMARY 
     According to one aspect, a system for a vehicle having a brake system comprises a retention device adapted to engage and secure a container to the vehicle responsive to operation of the brake system. 
     According to another aspect, a system for a vehicle having a brake system comprises a retention device adapted to engage and secure a container to the vehicle responsive to operation of the brake system, wherein the retention device comprises a housing, an actuator, a latch, a linkage device having a first link and a second link, and an actuation mechanism comprising a plunger and a spring. 
     According to yet another aspect, a method undertaken by a vehicle having a brake system comprises coupling a retention device adapted to engage and secure a container to the vehicle responsive to operation of the brake system, wherein the retention device comprises a housing, an actuator, a latch, and an actuation mechanism comprising a plunger and spring, and coupling the brake system to the actuation mechanism. The brake system comprises a first fluid reservoir, an orifice flow control device coupled to the first fluid reservoir via a first supply line, and a second fluid reservoir coupled to the orifice via a second supply line and to the actuation mechanism via a third supply line. Engaging the actuator of the retention device extends the latch into an orifice of the container, and the plunger of the actuation mechanism is extended into the latch of the container retention device. 
     Other aspects and advantages will become apparent upon consideration of the following detailed description and the attached drawings wherein like numerals designate like structures throughout the specification. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an isometric view of a container chassis incorporating container retention devices operative to secure a container thereto; 
         FIGS. 2 and 3  are exploded, fragmentary, isometric front and rear views, respectively, of the front container retention devices of  FIG. 1  and the container; 
         FIGS. 4-6  are bottom rear, top front, and top side fragmentary isometric views, respectively, of one of the container retention devices of  FIG. 2  shown in an unlatched state; 
         FIGS. 7 and 8  are top rear and top side isometric views, respectively, of one of the container retention devices of  FIG. 2  shown in a latching state; 
         FIGS. 9 and 10  are combined isometric sectional and elevational sectional views taken generally along the lines  9 - 9  of  FIG. 7 ; 
         FIG. 11  is a sectional view taken generally along the lines  11 - 11  of  FIG. 7 ; 
         FIG. 12  is an isometric view of the actuator of  FIGS. 4-6 ; 
         FIG. 13  is a fragmentary isometric view of the container retention device of  FIGS. 4-8  with portions removed therefrom to reveal interior components; 
         FIG. 14  is a sectional view taken generally along the lines  14 - 14  of  FIG. 13 ; 
         FIG. 15  is a fragmentary sectional view taken generally along the lines  15 - 15  of  FIG. 7  before movement toward the latching position; 
         FIG. 16  is a fragmentary isometric view of the container retention device of  FIGS. 4-8  with portions removed therefrom to reveal interior components; 
         FIG. 17  is a fragmentary sectional view taken generally along the lines  17 - 17  of  FIG. 7  before movement toward the latching position; 
         FIG. 18  is a simplified fragmentary sectional view, taken generally long the lines  18 - 18  of  FIG. 2 , of the container latched to the chassis by the container retention device; 
         FIG. 19 . is a simplified schematic illustration of the exemplary brake system; and 
         FIG. 20  is an elevational view of brake controls that control air supply to various braking components. 
     
    
    
     DETAILED DESCRIPTION 
     Various latching devices for use with a container chassis are described herein. As seen, such devices allow for the automatic latching and unlatching of an empty, filled, or partially filled container to and from a container chassis. Furthermore, such devices in combination with a fluid system, such as a braking system, may allow for the automatic latching/locking and unlatching/unlocking of an empty, filled, or partially filled container to and from a container chassis. In the drawings, like reference numerals connote like structures throughout. 
     Referring to  FIGS. 1-3 , a container chassis  50  includes container latching devices to secure a container  52  thereto. More particularly, a pair of front latching structures  54  comprising spaced first or driver side and second or passenger side front container retention devices  54   a ,  54   b , respectively, is disposed at a front portion  56  of the chassis  50 , preferably at or adjacent associated front corners  58 ,  60  of the chassis  50 . Particularly, in the illustrated embodiment, the devices  54   a ,  54   b  are integral with or secured (such as by welds) to outboard ends of a transverse head beam  61  of the chassis  50 . Alternatively, the devices  54   a ,  54   b  may be integrated within the outboard ends of a transverse head beam  61  of the chassis  50 . A pair of rear latching structures  62  ( FIG. 1 ) comprising spaced first or driver side and second or passenger side rear container retention devices  64   a ,  64   b , respectively, is provided on a rear portion  65  of the chassis  50 , preferably at or adjacent associated rear corners  66 ,  68  of the chassis  50 . As seen in  FIGS. 1 and 2 , the container  52  includes front and rear pairs of castings  70 ,  72 , respectively, wherein the front pair  70  comprises a first or driver side front casting  70   a  and a second or passenger side front casting  70   b . The rear pair  72  comprises a first or driver side rear casting  72   a  and a second or passenger side rear casting  72   b . The castings  70   a ,  70   b ,  72   a ,  72   b  are preferably disposed at or adjacent front and rear corners  74   a ,  74   b ,  76   a ,  76   b , respectively, of the container  52 . 
     Each of the castings  70   a ,  70   b ,  72   a ,  72   b  may include a first or bottom opening  80   a ,  80   b ,  82   a ,  82   b , respectively. In addition, each of the castings  70   a ,  70   b  may include forward-facing openings  84   a ,  84   b  while each of the castings  72   a ,  72   b  may include rearwardly-facing openings  86   a ,  86   b , respectively. Each of the castings  70 ,  72  may include a lesser or greater number of openings, for example, openings may be provided on side surfaces thereof or the front castings  70   a ,  70   b  may include only the forward facing openings  84   a ,  84   b , respectively. In any event, each casting  70 ,  72  has at least a necessary number of properly-positioned openings such that, when the container  52  is disposed on the chassis  50 , one or more portions of the container retention devices  54   a ,  54   b ,  64   a ,  64   b  extend into one or more of the casting openings  80 ,  82 ,  84 , and/or  86  to allow securement of the container  52  to the chassis  50  as described hereinafter. 
     The container chassis  50  shown in the embodiment in  FIG. 1  may have a length of 40 to 53 feet, for example. Differently-sized containers may be accommodated on the chassis  50  by providing a greater number of container latching devices and/or castings as required to secure the container  52  in a stable fashion. Still further, a container chassis having a length of 20 feet (not shown) may alternatively utilize the latching arrangements described herein in the rear and/or front portions of the container chassis. 
     In the embodiment shown in  FIGS. 1-3 , the front container retention devices  54   a ,  54   b  are mirror images of one another, but are preferably otherwise identical, and hence, only the driver side retention device  54   a  will be described in detail herein. 
     Referring next to  FIGS. 4-6 , the retention device  54   a  includes a housing  100  having an elongate slot  102  that extends fully through the housing  100  and further extends linearly from a first wall  104  through a corner  106  to a second wall  107  of the housing  100 . The housing  100  encloses a retention mechanism  108  therein. 
     The retention mechanism  108  comprises an actuator  120  (seen in detail in  FIG. 12 ) having an approximate L-shape including first and second legs  112 ,  114 , respectively, and first and second openings  116 ,  118  disposed at an end portion  121  and a heel portion  122 , respectively. As best seen in  FIGS. 5 and 6 , the end portion  121  is disposed between a clevis formed by pair of aligned anchors  124 ,  126  and is rotatably secured therebetween by a pin  130  and snap or lock ring  132 . Referring also to  FIGS. 13-17 , the second opening  118  (best seen in  FIG. 15 ) receives a pin  134  and a spacer  136  bears against the heel portion  122 . The pin  134  extends through aligned cross-openings  138 ,  139  in first and second link halves  140 ,  142 , respectively, (all best seen in  FIGS. 14 and 15 ) wherein the link halves together define a first portion  144  of a first link assembly  146  ( FIGS. 5 and 6 ) (the link half  140  and other structures are omitted in  FIG. 13  to illustrate the internal structures of the portion  144 ). Opposed snap or lock rings  147   a ,  147   b  disposed on ends of the pin  134  rotatably secure the link halves  140 ,  142  to the spacer  136  and the heel portion  122 . A proximal end  148  of a longitudinal cylindrical shaft  149  ( FIGS. 14 and 15 ) is slidably disposed in a cross bore  150  extending through the shaft  137  and extends toward a second portion  156  of the first link assembly  146 . 
     A first tube  160  is disposed in a recess  162  ( FIGS. 5, 6, 13, and 14 ) defined by upper flanges  164   a    166   a  and lower flanges  164   b ,  166   b  ( FIG. 15 ) of the link halves  140 ,  142 . The first tube  160  is retained in the recess  162  in any suitable fashion, such as by being captured between the flanges  164  and  166 . In a preferred embodiment, the first tube  160  is welded to the flanges  164  and  166 . Also, in alternative embodiments, the flanges  164  and  166  are either a single, integral flange, or are welded together and/or together may partially or fully encircle the first tube  160 . A first end  167  ( FIGS. 14 and 15 ) of a spring  168  is received in the first tube  160  and surrounds the shaft  149 . 
     The second portion  156  of the first link  146  is substantially a mirror image of the first portion  144  and includes first and second link halves  170 ,  172  that define the second portion  156  and a second tube  174  disposed and retained in any suitable fashion (such as noted above with respect to the first tube  160 ) between upper flanges  176   a ,  178   a  and lower flanges  176   b  and  178   b  of the link halves  170 ,  172 , wherein a second end  180  ( FIGS. 14 and 15 ) of the spring  168  is disposed in the second tube  174  and may be compressed between end surfaces of the tubes  160 ,  174 . Unlike the first portion  144 , a distal end  182  of the shaft  149  is immovably secured and retained in a bore  184  defined between the link halves  170 ,  172 . 
     A second link assembly  200  includes spaced second link assembly arms  202 ,  204  that are secured together at lower ends  202   a ,  204   a  thereof by a pin  206  with a distal end  212  of the second portion  156  of the first link  146  being disposed between and rotatable with respect to the second link assembly arms  202 ,  204 . In the illustrated embodiment, the pin  206  is press fitted and welded to assembly arm  204 . A snap or lock ring  208  secures the arms  202 ,  204  together at a proximal end of the pin  206 , wherein the pin  206  includes a groove  214  proximate the assembly arm  202 . A return spring  216  includes a first end  216   a  that is wrapped over the pin  206  inside the groove  214  and a second end  216   b  of the spring  216  is secured to an anchor tab  218  integral with or secured to the housing  100 . In an alternate embodiment, the assembly arm  202  may be omitted and the pin  206  is press fitted and/or welded to assembly arm  204 . As in the previous embodiment, the first end  216   a  of the return spring  216  is wrapped over the pin  206  inside the groove  214  and a second end  216   b  of the spring  216  is secured to an anchor tab  218 . A distal end  212  of the second portion  156  of the first link is rotatable with respect to the second link assembly arm  204 . 
     As seen in  FIGS. 14, 16, and 17 , a mid-portion  204   b  of the link assembly arm  204  is rotatably secured to an anchor plate  220  by a pin  222 , a spacer  224 , and a snap or lock ring  226 . The anchor plate  220  may be integral with or secured to the housing  100  and is stationary with respect to the housing  100 . Similar to the pin  206 , a proximal end of pin  222  is press fitted within and welded to assembly arm  204 , and a distal end of the pin  222  passes through the anchor plate  220  and the spacer  224  and is secured by a snap or lock ring  226 . 
     Referring again to  FIGS. 5 and 6  (which illustrate the container retention device in an unlatched state) and  FIGS. 9 and 10  (which illustrate the container retention device in the process of moving toward a fully latched state), each of upper ends  202   c ,  204   c  of the second link assembly arms  202 ,  204  includes elongate slots  202   d ,  204   d  that receive an elongate circular cylindrical shaft  230  that is immovably mounted in a bore  232   FIG. 9 ) disposed near a first end  234  of a latch  236 . First and second bearings sets  238  and  240  are disposed between an outer surface  242  of the shaft  230  and inner surfaces that define the slots  202   d ,  204   d , respectively. The bearings  238  and  240  as well as a further or third set of bearings  244  are held at spaced axial locations on the shaft  230  by spacers  246   a - 246   d  and snap or lock rings  248   a ,  248   b . The third set of bearings  244  includes an outer race that contacts and rides on and/or along a racetrack-shaped surface  250  defining a slot of a longitudinal member  252  mounted to opposite front and rear sides of the housing  100 . 
     The latch  236  includes a bore  254  ( FIGS. 5, 6, 9, 10, 13, and 14 ), that may extend partially or fully through the latch  236 . A selectively controllable actuation mechanism  260 , ( FIGS. 4-6, 9, and 10 ) which may be a hydraulic piston and cylinder device, a solenoid, or another controllable motive power device, includes an actuator plunger  261  ( FIGS. 9 and 10 ) that is movable into and retractable from the bore  254 , as noted in greater detail below. The latch  236  further includes a locking member  262  ( FIGS. 4, 9, and 10 ) that may be integral with the balance of the latch or may be secured thereto. The latch  236  and/or locking member  262  extend through a cylindrical collar  256  ( FIGS. 9 and 10  as well as other FIGS.) that is joined to or integral with the housing  100  and that provides support for the latch and/or locking member  262 . 
     In operation, before a container  52  is placed on the chassis  50 , the various elements of the container retention device  54   a  are in the positions shown in  FIGS. 4-6 and 13-17 . Thus, the actuator  120  is disposed in a fully extended position outside of the housing  100 . In this state, the return spring  216  exerts a restraining force on the second link assembly  200 , which causes the second link assembly  200  to be positioned at an extreme clockwise position (as seen in  FIG. 6 ) about the shaft  230 . Such positioning causes the latch  236 , and thus the locking member  262 , to assume a fully retracted position within the housing. 
     As seen in  FIGS. 1-6 , as a container  52  is lowered and/or brought from the rear toward the container retention device  54   a , a lower surface or front surface of the container  52  contacts an end surface  112   a  or a top surface  112   b  of the leg  112  of the actuator  120 , thereby exerting a force on the actuator  120  having a component in a directional range at or between approximate directions represented by force vectors F 1  and F 2  shown in  FIG. 6 . Continued advancement of the container  52  in such manner causes the actuator  120  to pivot downwardly and inwardly relative to the housing  100  in the direction of an arrow  270  ( FIGS. 5 and 6 ) about the pin  130 . The shape of the actuator  120  and the rotatable connection of the actuator  120  with the first portion  144  via the pin  134  results in translation of the first portion  144  along a path shown by the arrow  272  of  FIG. 6  that is substantially parallel to a path traversed by the actuator  120 . 
     Movement of the first portion  144  along the path illustrated by the arrow  272  causes forces to be transferred to the second portion  156  of the first link assembly  146 . In this regard, the spring  168  is sufficiently stiff to transmit forces effectively to the second portion  156  to move the latter in the direction of the arrow  272  when the latch  236  and locking member  262  are free to extend. On the other hand, the spring  168  is sufficiently compliant to compress and take up motion and limit forces transmitted to the second portion  156  when the latch  236  and locking member  262  are unable to move in the extension direction as a result of, for example, misalignment of the locking member  262  relative to the front opening  84   a  of the casting  72   a  resulting in blocking of the locking member  262 . In this regard, the longitudinal shaft  149  prevents the spring  168  from winding up on itself when the latter is compressed. 
     Referring also to  FIGS. 7, 8 and 11 , movement of the second portion  156  in the direction of the arrow  272  causes the second link assembly  200  to rotate about the pin  222  in a counterclockwise direction (as seen in  FIG. 11 ). Such rotation initially causes the bearings  238  and  240  seen in  FIGS. 9 and 10  to move down in the elongate slots  202   d ,  204   d  and the bearings  244  to move to the left in the slot  251  as illustrated in  FIG. 7 . The bearings  238 ,  240  eventually move upwardly in the slots  202   d ,  204   d , respectively, as the bearings  244  continue to move to the left in the slot  251 . The latch  236  and locking member  262  are carried by the second link assembly  200 , if not blocked or prevented by movement as noted above. Eventually, the locking member  262  moves to a fully extended position through the opening  84   a  into the casting  70   a  when the container  52  is fully seated on the chassis  50 . The shapes and sizes of the surfaces  202   e ,  204   e , and  250  defining the slots  202   d ,  204   d , and  251 , respectively, and the diameters of the outer races of the bearings  238 ,  240 , and  244  are selected to ensure smooth operation of the retention device  54   a.    
     A seen in  FIG. 18 , the relative sizes of the locking member  262  and the opening  84   a  and the space inside the casting  70   a  results in secure retention of the respective corner of the container  52  on the chassis  50 . Referring again to  FIGS. 4-10  at such time, the actuation mechanism  260  may be automatically or selectively operated to move the plunger  261  into the bore  254 . In one embodiment, the actuation mechanism  260  is spring-loaded so that when the bore  254  moves into alignment with the plunger  261 , the actuation mechanism  260  automatically moves the plunger  261  under spring force into the bore  254 . 
     In another embodiment, the actuation mechanism  260  is operated by a fluid system, such as one or more portions of an air brake system used in a conventional transport vehicle that transports a container as described hereinafter, to extend the plunger  261  into the bore  254 , and thereby lock at least the front of the container  52  to the chassis  50  until released as noted below. As is known, an air brake system typically includes a front brake air system (service brakes) and a rear brake air system (service, parking, and emergency brakes). 
     Specifically, referring to  FIG. 19 , a portion of the brake system  274  comprises a compressor  352 , a governor  354 , and a first fluid reservoir  356 , such as a tractor primary or other reservoir alone or a combination of such reservoirs. A container locking system  370  comprises a pressure-compensated flow control valve  377 , a second fluid reservoir  360 , such as a trailer air reservoir, and actuation mechanisms  260   a ,  260   b  of the driver side front container retention device  54   a  and passenger side front container retention device  54   b , respectively. 
     In the illustrated embodiment, when the vehicle engine is running, air is compressed by the compressor  352  and transferred to the first fluid reservoir  356  through a discharge line  362 . The governor  354  controls the magnitude of fluid pressure in the first fluid reservoir  356  between cut-in and cut-out levels of about 100 psi and about 125 psi, for example. Compressed air from the first fluid reservoir  356  is transferred to a foot valve (not shown) through a supply line  366  and to the service brake system  275  comprising associated brake assemblies. Compressed air is also transferred through a second supply line  374  to an inlet  376  of the flow control valve  377 . The flow control valve  377  comprises a parallel combination of a variable orifice  358  and a check valve  359 . It may be noted that the variable orifice  358  may be replaced by a fixed orifice, if desired. The flow control valve  377  further includes an outlet  378  coupled to the second fluid reservoir  360  via a third supply line  380 . In an alternative embodiment, the outlet  378  may be coupled to the second fluid reservoir  360  directly, such as by a a male/female stud coupling. As noted in greater detail hereinafter, if the primary reservoir  356  has lost pressurization, the flow control valve  377  is operable to maintain at least a selected magnitude of fluid pressure in the second fluid reservoir  360  for a duration of about 30 seconds, for example. Furthermore, in a particular embodiment, the cracking pressure, or the minimum pressure differential needed between the inlet  376  and outlet  378  for fluid to flow through the check valve  359  is about 1 psi to about 3 psi, for example. In an embodiment, the second fluid reservoir  360  may include a pressure sensor and control apparatus (not shown) similar to the governor  354 , wherein the cut out level is 125 psi, and the cut in level is 85 psi. If the second fluid reservoir includes such a sensor, the operator of the vehicle may be alerted when the fluid pressure inside the second fluid reservoir  360  has dropped to a certain level, such as about 60 psi or less. In such a case, the loss of fluid pressure is signaled to warn the operator of an imminent potential failure of the container locking system  370 . 
     Furthermore, the second fluid reservoir  360  is coupled to the actuation mechanism  260   a  of the driver side front container retention device  54   a  via a fourth supply line  382  and to the actuation mechanism  260   b  of the passenger side front container retention device  54   b  via a fifth supply line  384 . Because the actuation mechanism  260   a  of the driver side front container retention device  54   a  and the actuation mechanism  260   b  of the passenger side front container retention device  54   b  are mirror images of one another, but are preferably otherwise identical, only the portion of the brake system  274  coupled to the actuation mechanism  260   a  of the driver side front container retention device  54   a  will be described in detail herein, it being understood that actuation mechanism  260   b  of the retention device  54   b  operates identically. 
     As shown in  FIG. 19 , the actuation mechanism  260   a  of the driver side front container retention device  54   a  comprises a fluidic (e.g., pneumatic) piston and cylinder device including an actuation plunger  261   a  comprising a piston  388   a  coupled to a piston rod  389   a , and a biasing compression spring  386   a  disposed in a cylinder  391   a . The biasing spring  386   a  is disposed in compression between an end surface  387   a  of a first cylinder head  392   a  and the piston  388   a  and surrounds the piston rod  389   a . The piston rod  389   a  extends outwardly through the cylinder head  392   a  and is capable of left-right movement as seen in  FIG. 19 . A second cylinder head  394   a  is spaced from the first cylinder head  392   a  and defines a space  396   a  for receipt of pressurized air via the supply line  382 . Fluid pressure, such as pressurized air, may be transferred from the second fluid reservoir  360  to the space  396   a.    
     When the fluid pressure in the space  396   a  develops a force that exceeds the biasing force of the spring  386   a , the piston  388   a  and piston rod  389   a  move outwardly to an extended or locked position (i.e., to the right as seen in  FIG. 19 ), and, in one embodiment, assuming the container  52  is disposed on the chassis  50 , an end of the piston rod  389   a  moves one or more separate rod(s), plunger(s), or other element(s), such as the above-described plunger  261   a  connected to the end into the bore  254   a . In an alternate embodiment, the end of the piston rod  389   a  directly extends into the bore  254   a  of the latch  236   a  without any intervening elements therebetween. 
       FIG. 20  illustrates first and second brake controls  410  and  412 , respectively. The brake controls are typically located in the tractor cab to facilitate easy access thereto by the vehicle operator or other personnel. The brake controls may alternatively be at another location, such as on the chassis  50 . The first control  410  comprises a parking brake control. An operator or other personnel may pull the control  410  to an outer position to exhaust the pressurized air in the first fluid reservoir  356 , thereby causing the brake assemblies to apply braking forces to some or all of the wheels of the tractor/trailer system. Pushing the control  410  to an inner position causes pressurized air to be directed into the first fluid reservoir  356  (provided the available air pressure is above a certain level), thereby releasing the braking forces to some or all of the wheels of the tractor/trailer system. 
     Similarly, pulling the second brake control  412  to an outer position results in the application of braking forces in an emergency braking mode to some or all of the wheels of the trailer system. On the other hand, pushing the second brake control  412  in when there is sufficient pressure in the first fluid reservoir  356  releases the braking forces on some or all of the wheels of the trailer system. 
     A method of operating the above-described components to secure/remove a container  52  to/from the chassis  50  (trailer) of a tractor/trailer vehicle comprises the following steps under the assumptions that the chassis  50  is initially empty, the chassis  50  (sometimes referred as the trailer) is not coupled to the tractor, and the second (i.e., trailer) reservoir is depressurized. Upon arrival of the tractor at a desired loading location, the tractor is mechanically coupled to the chassis  50 . The operator or other personnel may then pull the brake control  412 , in turn causing air is to be exhausted from the first fluid reservoir  356  and initiating the emergency braking mode. The chassis  50  is then coupled to the tractor via glad hands (not shown). Since no fluid pressure is available to transfer from the first fluid reservoir to the second fluid reservoir and ultimately to the spaces  396  in the actuation mechanism  260  of both the driver side front container retention device  54   a  and the passenger side front container retention device  54   b , the actuation plungers  261  are in a retracted state (i.e., not extended). Next, when the container  52  is lowered and/or placed on the chassis  50 , the actuators  120  are moved to the retracted position so that the locking members  262  extend outwardly and move into the castings  70 . The relative sizes of the locking members  262 , the openings  84 , and the spaces inside the castings  70  result in secure retention of the corners of the container  52  on the chassis  50 . After the locking members  262  extend into the corner castings  70 , the operator or other personnel may push the second brake control  412 . Pressurized air released into the first reservoir  356  causes the braking system to transition out of the emergency braking mode and the pressurized air is transferred from the first fluid reservoir  356  though the check valve  359  into the second reservoir  360 . Pressurization of the secondary reservoir  360  causes the piston rod  389   a  of the actuation mechanism  260   a  and a corresponding piston rod  389   b  of the actuation mechanism  260   b  to move to the extended positions into the bores  254 . The pressure in the secondary reservoir  360  maintains the piston rods  389  in the extended positions so that the front corners of the container  52  are locked to the chassis  50  and cannot be disengaged from the container retention device  54  nor can the container  52  be lifted from the chassis  50  until the forces developed by the fluid pressures in the spaces  396  no longer exceed the biasing forces of the springs  386   a ,  386   b.    
     To remove the container  52  from the chassis  50 , an operator brakes to a stop and, while the tractor/trailer is not moving, the emergency braking mode is activated by pulling the second control  412 . Pressurized air is exhausted from the primary reservoir  356 , applying braking forces to the tractor/trailer braking system. A pressure differential is created between the secondary reservoir  360  and the primary reservoir  356  causing air to be metered through the variable orifice  358 , wherein the secondary reservoir  360  eventually depressurizes to a level insufficient to result in forces that are able to resist the forces of the spring  386   a  in the actuation mechanism  260   a  and a corresponding spring  386   b  in the actuation mechanism  260   b . As noted above, this depressurization level may be reached at a selected delay time, such as 30 seconds following pulling of the control  412 . At such time the piston rods  389   a  and  389   b  move to a retracted position such that the plungers  261  (or the ends of the piston rods  389 , as the case may be) are spaced from the the latch  236  and locking member  262  ensuring that the actuators  120  are able to move to the extended positions outside of the housings  100 . Upon deactuation of the container retention devices (and any devices restraining other portion(s) of the container  52 ), the container  52  may then be removed from the chassis  50 . 
     Similarly, if there is a loss in fluid pressure in the first fluid reservoir  356  while the tractor engine is running and the tractor/trailer is moving, the flow control valve  377  continues for the selected delay time to provide enough pressure to the second fluid reservoir  360  to keep the piston rods  389   a ,  389   b  in the extended position so that the container  52  remains locked on the chassis  50  for the selected delay time. The loss of air pressure in the reservoir  356  is typically indicated by an alarm, which, when actuated, indicates that the driver should stop the vehicle at the earliest possible time. The selected delay time that the container  52  remains locked on the chassis  50  is preferably sufficient to allow the driver to safely pull over, but not so long to hinder unloading of the container  52  from the chassis  50  after the tractor/trailer is stopped. 
     The rear castings  72   a ,  72   b  may be locked to the chassis  50  by the container retention devices  64   a ,  64   b , which may be of the type disclosed in co-owned U.S. Pat. Nos. 9,387,792, 9,463,732, 9,802,526, and/or 9,340,146 incorporated by reference herein. Alternatively, rear container retention devices comprising actuation mechanisms could be used to secure the rear corners of the container  52  to the chassis  50  that are identical or similar to the front container retention devices  54   a ,  54   b  with the exception that the rear retention devices include forwardly extending latches and locking members, as opposed to the rearwardly extending latches and locking members of the retention devices  54   a ,  54   b.    
     As should be evident, if the vehicle engine has not been running and the second fluid reservoir  360  has depressurized, no fluid pressure is available for transfer to the spaces  396  in the actuation mechanisms  260  and the container  52  is unlocked, and, upon deactuation of the container retention devices, the container  52  may then be removed from the chassis  50 . 
     In an alternative embodiment, actuation of the parking brakes using the control  410  may likewise cause ultimate depressurization of the reservoir  360 , leading to unlocking of the container  52 . 
     As described above, the fluid in the system may be air, or may be any other fluidic substance. 
     In summary, the container  52  by may be selectively released from the retention devices  54   a ,  54   b  (and remaining retention devices) by operating the actuation mechanisms  260  to retract the plungers  261  (or other structures) from the bores  254 . As should be evident from the foregoing, such operation may be undertaken automatically when a condition arises, such as when emergency or parking braking modes are activated, or when pressure is otherwise lost in the second reservoir  356 . When using front container retention devices  54 , the container  52  may be lifted upwardly, causing retraction of the latches  236 /locking members  262  from each of the front castings  70   a ,  70   b , under the influence of the return springs  216  of the retention devices  54  so that the container  52  is released from the retention devices  54 . Likewise, if rear container retention devices similar to the front retention devices  54  are used, upward movement of the container  52  causes retraction of the latches  236 /locking members  262  from each of the rear castings  72   a ,  72   b  under the influence of the return springs of the rear retention devices so that the container  52  is released from the rear retention devices. 
     In alternative embodiments, locking and/or unlocking of the container  52  to/from the chassis  50  may be undertaken manually by applying to or exhausting a pressurized fluid in a manner other than as described above from the appropriate sides of the pistons of the mechanisms  260 . Alternatively, electric power may be supplied to or removed from the mechanism  260  when a solenoid is used as the mechanism  260  or when a solenoid is used to activate/deactivate one or more valves that pressurize/depressurize appropriate sides of the pistons of the mechanisms  260 . Still further, a handle (not shown) may be used to extend and/or retract the plungers  261  whether a spring force is or is not applied to the plungers  261 , etc. 
     In each embodiment the retention devices  54  and the brake system  274  are preferably failsafe in nature such that, if there is a loss of fluid pressurization or electrical power that occurs while the chassis  50  is in motion the retention devices  54  maintain the locking member  262  and the plunger  261  in the extended positions to maintain securement of the container  52  to the container chassis  50  for at least a limited amount of time as noted above. 
     INDUSTRIAL APPLICABILITY 
     As described above, the container retention devices  54  utilize one or more elements of the brake system  274  to secure the container  52  to the vehicle, more specifically to the chassis  50  of the vehicle, once the container  52  is placed on the chassis  50 . The container  52  remains secured to the chassis  50  until selectively released. In the preferred embodiment, the container  52  is locked to the chassis  50  until a predetermined time after the vehicle has come to a stop, and/or the emergency or parking brakes have been engaged. 
     All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein. 
     The use of the terms “a” and “an” and “the” and similar references in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the disclosure and does not pose a limitation on the scope of the disclosure unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the disclosure. 
     Numerous modifications to the present disclosure will be apparent to those skilled in the art in view of the foregoing description. It should be understood that the illustrated embodiments are exemplary only, and should not be taken as limiting the scope of the disclosure.