Abstract:
A valve closure assembly ( 50 ) for remotely and automatically closing a railway tank car valve (V 1,  V 2,  V 3,  V 4 ), characterized by improved convenience in mounting on a tank car dome ( 160 ) and adaptability to various dome geometries, valve configurations, and car-to-car dimensional variations. A clamp assembly ( 52 ) mounts assembly ( 50 ) on dome ( 160 ). An adapter ( 180 ) operated by a motor ( 58 ) turns a valve handle (A 1,  A 2,  A 3,  A 4 ) when motor ( 58 ) runs. A positioning mechanism ( 54 ) selectively positions adapter ( 180 ) relative to clamp assembly ( 52 ) to establish a spatial relationship between them for enabling clamp assembly ( 52 ) to be placed at a desired location on the dome wall ( 162 ) and adapter ( 180 ) to engage a valve handle. Positioning mechanism ( 54 ) comprises three degrees of freedom of motion for establishing the spatial relationship of adapter ( 180 ) to clamp assembly ( 52 ), two of which are in the horizontal plane.

Description:
REFERENCE TO RELATED APPLICATION AND PRIORITY CLAIM  
       [0001]    This application derives from the following commonly owned co-pending patent application, the priority of which is expressly claimed: Provisional Application No. 60/374,652, filed on Apr. 22, 2002 in the names of Richard Fortino and David N. Maniez Jr. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    This invention relates to a valve closure system and valve closure assembly for promptly and automatically closing tank valves, especially tank valves of railway tank cars. The invention also relates to methods of making and using the valve closure assembly.  
         BACKGROUND OF THE INVENTION  
         [0003]    Various fluids are transported by railway tank cars. Such tank cars have domes where various valves are located. The portions of the valves that are external to the tank, including the valve handles are housed within a protective housing that has a hinged lid or cover that is opened to expose the handles. One or more of the valves is opened during certain procedures involving loading and/or unloading fluid into and/or from the tank. During such procedures, a valve closure assembly having a power actuator is hoisted onto the dome and mounted there. The power actuator is fitted to the handle of the open valve and can be remotely and automatically operated to close the open valve when conditions call for valve closing.  
         SUMMARY OF THE INVENTION  
         [0004]    The present invention relates to improvements in valve closure assemblies for remotely and automatically closing an open tank car valve when conditions call for valve closing. The inventive valve closure assembly is characterized by improved convenience in mounting and use on a railway tank car and by better adaptability to various types of protective housings and various tank car valve configurations within the housings. It is tolerant of car-to-car variations in standard dimensions that are promulgated by industry for various valve configurations. The inventive principles include methods of making and using the valve closure assembly, and certain aspects of the invention may be useful in other than the context of a railway tank car.  
           [0005]    One generic aspect of the invention relates to an assembly for turning an external handle of a tank dome valve about a vertical axis. The assembly comprises a mounting for removably mounting the assembly on a tank dome and an adapter operated by a motor for engaging the valve handle and turning the handle when the motor operates. The assembly further comprises a positioning mechanism for selectively positioning the adapter relative to the mounting to establish a spatial relationship of each to the other for enabling the mounting to be placed at a desired location on the dome and the adapter to engage the valve handle. The positioning mechanism comprises two degrees of freedom of motion in a horizontal plane for establishing the spatial relationship of the adapter to the mounting in the horizontal plane.  
           [0006]    Another generic aspect of the invention relates to an assembly for turning an external handle of a tank dome valve about a vertical axis where the assembly comprises a mounting for removably mounting the assembly on a tank dome, an adapter operated by a motor for engaging the valve handle and turning the handle when the motor operates, and a positioning mechanism for selectively positioning the adapter relative to the mounting to establish a spatial relationship of each to the other for enabling the mounting to be placed at a desired location on the dome and the adapter to engage the valve handle. The positioning mechanism comprises three degrees of freedom of motion for establishing the spatial relationship of the adapter to the mounting.  
           [0007]    Another generic aspect of the invention relates to a method of associating a valve operating assembly with a fluid-containing tank for enabling an adapter that is operated by a motor of the valve operating assembly to turn an external handle of a valve on the tank about an axis of turning while a mounting of the assembly is supporting the assembly on the tank. The method comprises relatively positioning the mounting and the adapter via a positioning mechanism of the valve operating assembly that has two degrees of freedom of motion in a plane of reference that is perpendicular to the axis of turning to establish a spatial relationship of the mounting and motor to each other in the plane of reference for placing the adapter in engagement with the valve handle and placing the mounting at a desired location on the tank.  
           [0008]    Another generic aspect of the invention relates to a method of associating a valve operating assembly with a fluid-containing tank for enabling an adapter operated by a motor of the valve operating assembly to turn a valve on the tank about an axis of turning while a mounting of the assembly is supporting the assembly on the tank wherein the method comprises relatively positioning the mounting and the adapter via a positioning mechanism of the valve operating assembly that has three degrees of freedom of motion to establish a spatial relationship of the mounting and motor to each other for placing the adapter in engagement with the valve handle and placing the mounting at a desired location on the tank.  
           [0009]    Still another generic aspect of the invention relates to a method of associating a valve operating assembly comprising a mounting, a positioning mechanism, and an adapter operated by a motor with a dome of a fluid-containing tank comprising a valve having a handle that is external to the tank and an upright wall spaced horizontally from the valve handle for enabling the adapter to engage the valve handle and turn the handle about an axis of turning while the mounting is supporting the assembly at a desired location on the dome in horizontally spaced relation to the valve handle. The method comprises disposing the valve operating assembly vertically over the dome, lowering the assembly onto the dome, and causing the positioning mechanism to relatively position the mounting and the adapter to place the adapter in engagement with the valve handle and to place the mounting at a desired location on the upright wall.  
           [0010]    The foregoing features, advantages, and aspects of the invention, along with additional ones, will be seen in the ensuing description and claims, which are accompanied by drawings. The drawings disclose a presently preferred embodiment of the invention according to the best mode contemplated at this time for carrying out the invention. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]    [0011]FIG. 1 is a perspective view showing a presently preferred embodiment of valve closure system comprising a valve closure assembly according to the present invention.  
         [0012]    [0012]FIG. 2 is an exploded perspective view of FIG. 1.  
         [0013]    [0013]FIG. 3 is a top of plan view of FIG. 1.  
         [0014]    [0014]FIG. 4 is a vertical cross section view in the direction of arrows  4 - 4  in FIG. 3.  
         [0015]    [0015]FIG. 5 is a vertical cross section view in the direction of arrows  5 - 5  in FIG. 3.  
         [0016]    [0016]FIG. 6 is a vertical cross section view in the direction of arrows  6 - 6  in FIG. 3.  
         [0017]    [0017]FIG. 7 is a perspective view of a clamp assembly of the valve closure assembly.  
         [0018]    [0018]FIG. 8 is an elevation view in the direction of arrow  8  in FIG. 7.  
         [0019]    [0019]FIG. 9 is a right side elevation view of FIG. 8.  
         [0020]    [0020]FIG. 10 is a top view of FIG. 9.  
         [0021]    [0021]FIG. 11 is a perspective view of one element of the clamp assembly by itself.  
         [0022]    [0022]FIG. 12 is an elevation view in the direction of arrow  12  in FIG. 11.  
         [0023]    [0023]FIG. 13 is a right side elevation view of FIG. 12.  
         [0024]    [0024]FIG. 14 is a top view of FIG. 12.  
         [0025]    [0025]FIG. 15 is a perspective view of another element of the clamp assembly by itself.  
         [0026]    [0026]FIG. 16 is an elevation view in the direction of arrow  16  in FIG. 15.  
         [0027]    [0027]FIG. 17 is a right side elevation view of FIG. 16.  
         [0028]    [0028]FIG. 18 is a top view of FIG. 16.  
         [0029]    [0029]FIG. 19 is a perspective view of still another element of the clamp assembly by itself.  
         [0030]    [0030]FIG. 20 is an elevation view in the direction of arrow  20  in FIG. 19.  
         [0031]    [0031]FIG. 21 is a right side elevation view of FIG. 20.  
         [0032]    [0032]FIG. 22 is a top view of FIG. 20.  
         [0033]    [0033]FIG. 23 is a perspective view of an element of a motor head of the valve closure assembly by itself.  
         [0034]    [0034]FIG. 24 is an elevation view in the direction of arrow  24  in FIG. 23.  
         [0035]    [0035]FIG. 25 is a left side elevation view of FIG. 24.  
         [0036]    [0036]FIG. 26 is a perspective view of another element of the motor head by itself.  
         [0037]    [0037]FIG. 27 is an elevation view in the direction of arrow  27  in FIG. 26.  
         [0038]    [0038]FIG. 28 is a top view of FIG. 27.  
         [0039]    [0039]FIG. 29 is a right side view of FIG. 28.  
         [0040]    [0040]FIG. 30 is a perspective view of an element of a head positioning mechanism of the valve closure assembly by itself.  
         [0041]    [0041]FIG. 31 is a view in the direction of arrow  31  in FIG. 30.  
         [0042]    [0042]FIG. 32 is a bottom view of FIG. 31.  
         [0043]    [0043]FIG. 33 is a right side view of FIG. 32.  
         [0044]    [0044]FIG. 34 is a top plan view of the valve closure assembly mounted on a railway tank car.  
         [0045]    [0045]FIG. 35 is a front elevation view of FIG. 34.  
         [0046]    [0046]FIG. 36 is a perspective view of a direct drive adapter by itself.  
         [0047]    [0047]FIG. 37 is a top plan view of FIG. 36.  
         [0048]    [0048]FIG. 38 is a vertical cross section view in the direction of arrows  38 - 38  in FIG. 37.  
         [0049]    [0049]FIG. 39 is a cross section view in the direction of arrows  39 - 39  in FIG. 36. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0050]    [0050]FIGS. 1 through 6 illustrate a presently preferred embodiment of valve closure assembly  50  of a valve closure system in accordance with principles of the invention. The valve closure assembly is adapted for mounting on the dome of a railroad tank car and operative coupling with a handle of a valve on the tank car for enabling the valve to be automatically closed in a situation where immediate valve closure is called for.  
         [0051]    The dome of a representative of railroad tank car comprises a protective housing. The protective housing comprises a circular upright wall that is supported on a manway cover. The manway cover is supported on a flange of a circular manway opening in the tank dome. That assembly carries various valves whose handles are disposed external to the tank interior, but within the interior of the protective housing. Piping for the valves extends through the manway cover into the tank interior. The open top of the circular upright wall of the protective housing is closed by a circular cover that can be opened to provide access to the interior of the protective housing, and hence to the valve handles. With the cover open, the rim of the circular wall is exposed.  
         [0052]    The present invention utilizes the exposed rim of the circular wall of the protective housing for securely mounting valve closure assembly  50  on a tank car dome. Valve closure assembly  50  comprises a clamp assembly  52  for clamping on the rim of the circular wall of the protective housing, a positioning mechanism  54  that is supported on the clamp assembly, and a motor head  56  that is positioned by the positioning mechanism for operative association with a valve handle that will enable system  50  to promptly close the associated valve by turning the valve handle when called upon to do so.  
         [0053]    Motor head  56  comprises a motor  58 , preferably an air motor, that is mounted upright on a motor mounting  60 . Mounting  60  comprises a base plate  62  that is shown by itself in detail in FIGS. 26 through 29. Mounting  60  is securely fastened to positioning mechanism  54  through a rectangular tie bar  64  using screws  66 . A bracket  68  is fastened by fastening elements  70 ,  72  to base plate  62 . A handle  74  is in turn fastened to bracket  68  by fasteners  76 . Handle  74  comprises a handlebar  78  and a grip  80 .  
         [0054]    From this description it can be appreciated that mounting  60  comprises a horizontal platform on which motor  58  is securely mounted and a vertical wall that extends upward from that platform along side the motor. The horizontal portion of base plate  62  forms the horizontal platform of mounting  60 , and the vertical portion of base plate  62  and bracket  68  together form the vertical wall of the mounting. Handle  74  extends horizontally away from the side of that vertical wall opposite motor  58  near the upper end of the motor.  
         [0055]    The shank of a respective headed screw  81  passes through each of six holes  83  in base plate  62  to thread into a respective threaded hole in an end of the air motor body. Tightening of the screws secures motor  58  on motor mounting  60 . It is considered desirable to protectively enclose motor  58  by a circular cylindrical shield  82 . A circular ring  84  is disposed around the air motor body at one end and clamped to the air motor body using three set screws  85  that are threaded into tapped through-holes in ring  84 . One end of shield  82  fits over ring  84  to establish concentricity of the shield to the motor body and contains several clearance holes that allow the shanks of headed screws  87  to pass through and thread into tapped holes in ring  84 . These screws are tightened to secure the shield to the ring. An annular ring seal  86  closes the annular space between the shield and the motor body at the opposite end. The horizontal platform that base plate  62  provides to support motor  58  comprises a central through-hole  89  surrounded by the six holes  83 . Through-hole  89  allows the motor shaft  91  to pass downward through the horizontal platform where a direct drive adapter  180  is coupled to the shaft using a hitch pin  93 . The upper end of motor  58  remains exposed to provide for connection of an air line (not shown) to the motor.  
         [0056]    Positioning mechanism  54  comprises circular cylindrical rods  92 ,  94 , linear bearings  96 ,  98 , and a pillow block  100 . Rods  92 ,  94  are disposed horizontally spaced apart in mutually parallel relationship. Tie bar  64  at one end of rods  92 ,  94  and a second tie bar  102  at the opposite ends of the rods have counterbored through-holes that allow the rod ends to fit with precision to the counterbores of the tie bars. Screws  66  pass through the clearance holes  103  of one of four pairs of such clearance holes in base plate  62  to enter the through-holes in tie bar  64  and thread into tapped holes in the rods. The uppermost pair of holes  103  are used for fastening bracket  68  to base plate  62 , while the other three pairs provides for motor head  56  to be fastened to positioning mechanism  54  at any of three different elevations. Rods  92 ,  94  have tapped holes at their opposite ends, which seat with precision in the counterbores in the through-holes in tie bar  102 . Screws  104  fasten tie bar  102  and the rods together at that end in the same way so that the assembly of the two tie bars and the two rods forms a part of the positioning mechanism that can translate horizontally relative to pillow block  100 .  
         [0057]    Detail of pillow block  100  is shown in FIGS.  30 - 33 . Linear bearings  96 ,  98  are fit to respective through-holes  106 ,  108  in pillow block  100 . Rods  92 ,  94  pass through these linear bearings. Midway between and at a right angle to through-holes  106 , 108 , pillow block  100  comprises a vertical through-hole  110 . A linear bearing  112  is fit to through-hole  110 . A circular rod  114  that has tapped holes at opposite ends passes through linear bearing  112 . A stop disk  116  is fastened to the upper end of rod  114  using a screw  118 . A screw  120  fastens clamp assembly  52  to the lower end of rod  114 .  
         [0058]    During the process of assembling positioning mechanism, tubular bumpers  121  are fit onto ends of rods  92 ,  94  proximate each tie bar  64 ,  102 . Bumpers  121  limit the travel of pillow block  100  on rods  92 ,  94  so that the pillow block cannot strike either tie bar. The lengths of the bumpers are chosen to also provide sufficient clearance between the pillow block and the tie bars at the limits of pillow block travel so that pinch points are not present between the pillow block and the tie rods at the limits of pillow block travel.  
         [0059]    FIGS.  7 - 22  show that clamp assembly  52  comprises a bracket assembly  122  fabricated from two base clamp parts  124 ,  126  and a strengthener plate  128 . In addition to bracket assembly  122 , clamp assembly  52  comprises a hand screw  130  that can be manually turned by a turning knob  159  shown in FIGS.  1 - 4  and  6 .  
         [0060]    Part  126  is shaped to fit onto the rim of the protective housing of a railway tank car and comprises spaced apart vertical side walls  132 ,  134  that are joined by a horizontal top wall  136 , endowing the part with an inverted U-shape as shown by FIG. 17. When the part is fit onto the protective housing rim, wall  132  is disposed inside the rim, wall  134  is disposed outside the rim, and top wall  136  rests on the top edge surface of the rim. Hence walls  132 ,  134  are spaced apart a distance that is greater than the thickness of the protective housing rim.  
         [0061]    Part  124  is shaped to nest on part  126  and comprises a horizontal rectangular top wall  138  and legs  140 ,  142 ,  144 ,  146  depending from the four corners of top wall  138 . In the direction of the thickness of the protective housing rim, part  124  is longer than part  126 , but part  124  is shorter than part  126  in a direction at 90° to the thickness of the protective housing rim. Between leg  140  and leg  142 , part  124  has a downwardly open rectangular throat. A like throat exists between leg  144  and leg  146 . The two throats are dimensioned so that part  124  fits snuggly onto part  126 , as shown in FIGS. 7 and 9.  
         [0062]    Strengthener plate  128  is rectangular in shape and is disposed against the outer surface of side wall  134  and between the lower ends of legs  142 ,  146 . The three parts  124 ,  126 ,  128  are aluminum alloy and are joined together by any suitable metallurgical joining technique to form bracket assembly  122 .  
         [0063]    Top wall  138  has a circular hole  150  at its center that allows the lower end of rod  114  to pass through and abut top wall  136 . The latter wall has a countersunk hole  152  for allowing the flat head of screw  120  to seat flush in the countersink. Because the two walls  136 ,  138  are spaced vertically apart and rod  114  has a close fit to hole  150 , rod  114  is rigidly supported on clamp assembly  52 . Rigidity may be enhanced by joining rod  114  to wall  138 .  
         [0064]    Strengthener plate  128  comprises a tapped hole  154  into which the threaded shank  156  of hand screw  130  is threaded. Side wall  134  may have a clearance hole  157  for shank  156 , or it may provide an extension of the tapped hole in plate  128 . Although the thickness of wall  134  may be sufficient for the forces that it will experience during use of the valve closure system, that thickness may be insufficient to provide the desired length for the tapped hole needed for hand screw  130 . Strengthener plate  128  is therefore included to provide the desired tapped hole length into which shank  156  is threaded.  
         [0065]    FIGS.  34 - 35  illustrate an example of how valve closure assembly  50  is used on a railway tank car. The tank car has a centrally located dome that has a protective housing  160 . The protective housing comprises a circular upright side wall  162  on which a top cover (not shown) is hinged for opening and closing the housing. Side wall  162  is supported on a manway cover  164  that is part of an assembly that carries four valves V 1 , V 2 , V 3 , V 4  in this example. The valves comprise respective handles A 1 , A 2 , A 3 , A 4  that are disposed external to the tank interior, but within the interior of housing  160 . With the top cover swung open, the rim of side wall  162  is exposed.  
         [0066]    One or more of the valves is (are) opened, as appropriate to the particular procedure being performed on the tank car. A valve closure assembly  50  can be associated with the handle of any opened valve. The efficient geometry of valve closure assembly  50  allows multiple valve closure assemblies to be used concurrently. In this way a respective individual valve closure assembly  50  can be associated with a respective handle so that if all four valves are opened, they can be automatically closed by the respective valve closure assembly. The example shown in FIGS.  34 - 35  involves only a single valve closure assembly.  
         [0067]    With hand screw  130  backed off sufficiently to provide a clearance from the distal end of shank  156  to side wall  132  of clamp assembly  52  that is sufficiently greater than the thickness of the rim of protective housing side wall  162 , handle  74  can be grasped to position the valve closure assembly over protective housing  160  with bracket assembly  122  positioned over the housing side wall rim and the downwardly open throat of the bracket assembly aligned with the rim and with motor head  56  positioned over valve V 1  and direct drive adapter  180  aligned with handle A 1 . The valve closure assembly is then lowered until top wall  136  of bracket assembly  122  comes to rest on the top edge surface of the housing side wall rim and adapter  180  comes into engagement with handle A 1 . Turning knob  159  of hand screw  130  is then grasped and turned to advance shank  156  against the outside of the housing rim thereby locking clamp assembly  52  to the protective cover. Other apparatus of the valve closure system that is not shown in the drawings is able to operate motor  58  when handle A 1  is to be operated to close valve V 1 . During mounting of assembly  50  on a tank car, the linear bearings facilitate the ability of positioning mechanism  54  to achieve the desired positioning of motor head  56  relative to clamp assembly  52 . They also facilitate any movement that may occur when motor  58  is operated, such as vertical motion arising from valve handle travel as the valve handle is turning. The linear bearings are commercially available products that incorporate circulating balls. Assembly  50  also adapts to a range of variations in valve location, a range in departure of a valve axis from vertical, and a range of thickness of the protective housing rim, without compromising the ability of the assembly to close an open valve.  
         [0068]    Direct drive adapter  180  has features for fitting to handle A 1 . As motor  58  operates to turn the handle via adapter  180 , the handle may or may not translate vertically as it is turning. The range of vertical travel of pillow block  100  on rod  114  and a proper vertical setting of motor head  56  on tie rod  64  will enable the motor head to travel vertically with the valve handle so that the driving relation of the adapter to the handle is maintained until the valve is fully closed.  
         [0069]    FIGS.  36 - 39  show direct drive adapter  180 . It comprises a cylindrical hub  182  with a square drive hole  184  for fitting onto motor shaft  91 . A transverse hole  186  is arranged for registration with a hole in the motor shaft so that hitch pin  93  can pass through both holes to pin the adapter to the motor shaft. A base plate  188  at the end of hub  182  carries two drive pins  190  on the face of the base plate that is opposite hub  182 . Drive pins  190  are arranged in a geometric pattern that allows them to fit into diametrically opposite holes  192  in the handles when assembly  50  is associated with one of them (see FIG. 34).  
         [0070]    Because positioning mechanism  54  also endows the valve closure assembly with the ability to position motor head  56  at various horizontal distances from vertical rod  114 , it becomes possible to mount clamp assembly  52  within a range of locations around the rim of the protective housing with respect to a particular valve. This can be an aid to mounting of a valve closure assembly, particularly when multiple valve closure assemblies are used on a single tank car.  
         [0071]    Positioning mechanism  54  is therefore capable of selectively positioning adapter  180  relative to the clamp assembly  52  to establish a spatial relationship of each to the other for enabling the clamp assembly to be placed at a desired location on dome wall  162  and the adapter to engage a valve handle. Positioning mechanism  54  comprises three degrees of freedom of motion for establishing the spatial relationship of the adapter to the mounting of assembly  50  on wall  162  that is provided by clamp assembly  52 . Two of those degrees of freedom of motion are in a horizontal plane of reference. They are provided as circular translation along a horizontal arc by the ability of pillow block  100  to turn on rod  114  about the vertical rod axis and as linear translation of rods  92  horizontally on pillow block  100 . The third degree of freedom of motion is provided as vertical translation by the ability of pillow block  100  to travel vertically on rod  114 .  
         [0072]    Overall weight is reduced by using aluminum as the material of a number of the individual parts, such as clamp parts  124 ,  126 ,  128  and motor mount parts  62 ,  68 . An optional trapezoidal hole  170  in the upwardly pointing tongue of bracket  68  lightens its weight. Certain individuals will be able to carry a valve closure assembly  50  by grasping handle  74 , and able to install it on a tank car without help. A hole  172  near the tip end of the tongue of bracket  68  is available for attachment of an end of a lift or winch cable that can be used as an aid in lifting the valve closure assembly. Rectangular holes in side walls  132 ,  134  of bracket part  126  can lighten its weight. Assembly  50  can be used with a valve handle that is different from the ones shown by using an adapter that like adapter  180  attaches directly to motor shaft  91  using hitch pin  93 , but differs in how it mates with the particular valve handle.  
         [0073]    Further examples of various adapters are disclosed in commonly owned, non-provisional patent application of the same inventors, “Adapters And Adapter Systems For Valve Closure Systems And Valve Closure Assemblies”, Ser. No. ______, of even date, (Attorney Docket PowellUS09).  
         [0074]    While a presently preferred embodiment of the invention has been illustrated and described, it should be appreciated that principles of the invention are applicable to all embodiments that fall within the scope of the claims that follow hereinafter.