Patent Publication Number: US-2015059885-A1

Title: Valve assembly

Description:
TECHNICAL FIELD  
     The present disclosure relates to a valve, and more specifically to the valve used in sealing of a hydraulic tank. 
     BACKGROUND  
     A fluid tank associated with a machine is connected to a pump of the machine through a suction line. During servicing, such as, while replacing the pump or replacing an elastic coupling element of the pump, the pump needs to be disconnected from the fluid tank. 
     Generally, when the pump is disconnected from the fluid tank, the suction line is removed from the fluid tank, causing hydraulic fluid to spill out. The spilled hydraulic fluid may get contaminated and require replacement. This may also lead to contamination of the machine and environment. 
     W.O. Published Application Number 03/040575 relates to a hydraulic device with housing inside which is a space containing hydraulic fluid and an air volume. A breather assembly is further provided, having a breather duct extending between the outside atmosphere and the above-mentioned space, for aerating and de-aerating the above-mentioned space, in particular during the operation of the hydraulic device. The breather assembly is provided with shut-off means shut-off the breather duct until the hydraulic device is first put into operation. The hydraulic device is designed in such a way that when it is first put into operation the seal of the breather duct provided by the shut-off means is automatically and permanently removed. 
     SUMMARY OF THE DISCLOSURE  
     In one aspect of the present disclosure, a valve is provided for a hydraulic tank. The valve includes a main body and an end cap. The main body includes a first section, a second section and a window. The first section has a solid configuration. The first section has a shoulder configured to contact with a spring. The second section extends from the first section. The second section has a hollow configuration. The window defined on a surface of the second section is positioned towards an end of the second section proximate to the first section. The window is configured to selectively receive a fluid flow from the hydraulic tank into the main body based on a position of the valve with respect to the hydraulic tank. The end cap has a hollow configuration. The end cap is coupled to another end of the second section of the main body. 
     In another aspect, a hydraulic tank is provided. The hydraulic tank includes an outlet port and a valve. The outlet port discharges a fluid flow from the tank. The valve is positioned at least partially within the outlet port. The valve includes a main body and an end cap. The main body includes a first section, a second section and a window. The first section has a solid configuration. The first section has a shoulder configured to contact with a spring. The second section extends from the first section. The second section has a hollow configuration. The window defined on a surface of the section is positioned towards an end of the second section proximate to the first section. The window is configured to selectively receive the fluid flow from the hydraulic tank into the main body based on a position of the valve with respect to the hydraulic tank. The end cap has a hollow configuration. The end cap is coupled to another end of the second section of the main body. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an exemplary shearer machine, according to one embodiment of the present disclosure; 
         FIG. 2  is a perspective view of a power pack of the machine having a hydraulic tank and a pump; 
         FIG. 3  is an exploded view of a valve; 
         FIG. 4  is a cross sectional view of the hydraulic tank, the valve and a pipe, the valve being in an open position; 
         FIG. 5  is a cutaway view of the valve when the valve is in the open position; and 
         FIG. 6  is a cutaway view of the valve when the valve is in a closed position. 
     
    
    
     DETAILED DESCRIPTION 
     Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or the like parts. Referring to  FIG. 1 , an exemplary mining machine  100  is illustrated. More specifically, the machine  100  is a shearer. The machine  100  is configured for shearing of coal from a coal face of a coal mine It should be noted that in addition to the coal, the machine  100  may be used for shearing of any other mineral from a face of a respective mine. 
     Alternatively, the machine  100  may embody any other machine such as, but not limited to, a large mining truck, an articulated truck, and an off-highway truck. Further, according to various embodiments, the machine  100  may be any other machine associated with industries such as mining, agriculture, construction, forestry, waste management, and material handling, among others. 
     As shown in  FIG. 1 , the machine  100  includes a main frame  102  having a first end  104  and a second end  106 . The first end  104  includes an arm  108  pivotally coupled to the main frame  102 . A cutter  110  is rotatably affixed to the arm  108 . The cutter  110  includes blades  112  for the shearing of the coal from the coal face of the coal mine One or more hydraulic and/or pneumatic cylinders  114  are coupled to the main frame  102  and the arm  108 . The hydraulic cylinders  114  facilitate in moving to the arm  108  and aligning the cutter  110  against the coal face of the coal mine A similar arrangement of the arm  108  and the cutter  110  may be provided on the second end  106  of the main frame  102  for the shearing of the coal. Configuration, size, dimension and location of the arm  108  and the cutter  110  provided on the second end  106  may be different from that provided on the first end  104  according to system design and requirements. 
     The machine  100  may include an armored face conveyor (not shown). The armored face conveyor may include a conveyor or a set of chains for haulage of the coal sheared from the coal face. The armored face conveyor may also include a track for mobility of the main frame  102  of the machine  100  within the coal mine. Further, the armored face conveyor may include a hydraulic system (not shown) for advancement of the machine  100  against the coal face for shearing of a required quantity of the coal from the coal face. 
     The machine  100  may include a roof support unit (not shown). The roof support unit may be configured for providing temporary support to a roof of the coal mine during the shearing operation. Further, the machine  100  may include a power source (not shown) for providing power for operation of the machine  100 . The machine  100  may also include a drivetrain (not shown) coupled to the power source. The drivetrain may include any one or a combination of, but not limited to, gearing, differentials, drive shafts and hydraulic and/or pneumatic circuits including valves, lines, and distribution manifolds. The drivetrain may be configured to transmit power from the power source to the armored face conveyor, the cutter  110  and other operational components of the machine  100 . 
     As shown in  FIG. 1 , an enclosure  116  is provided on the main frame  102  of the machine  100 . The enclosure  116  houses a power pack  202  of the machine  100 . The power pack  202  is provided for increasing a pressure of a fluid which is supplied to the hydraulic cylinders  114  associated with the machine  100 . The fluid may be any known work fluid like, for example, oil. A perspective view of the power pack  202  is shown in  FIG. 2 . The power pack  202  may include various components, such as, but not limited to, a pump  204 , a pipe  206  and a hydraulic tank  208 . The hydraulic tank  208  may facilitate the storage of the fluid. Parameters related to the hydraulic tank  208 , such as shape, dimensions, material used and so on may vary based on the application. 
     The pump  204  may be mounted on a base plate  210 . In one embodiment, the pump  204  may be of a positive displacement type such as, but not limited to, a vane pump, a screw pump, and a diaphragm pump. In another embodiment, the pump  204  may be a rotodynamic type like a centrifugal pump or any other known design may be utilized. In one embodiment, the pump  204  may be selectively connected to the hydraulic tank  208  through the pipe  206 . The pipe  206  is connected to the hydraulic tank  208  at an outlet port  212  (see  FIG. 4 ) of the hydraulic tank  208 , the outlet port  212  being located at a bottom portion of the hydraulic tank  208 . The pipe  206  may be manufactured from a flexible material or any known metal. 
     An exploded view of a clamping arrangement  216  provided at one end of the pipe  206  is shown in  FIG. 2 . This end of the pipe  206  may be attached to the hydraulic tank  208  through the clamping arrangement  216 . The clamping arrangement  216  may include a flange  218  provided at the given end of the pipe  206 , a flange clamp  220 , bolts  222  and a sealing ring  224 . In one embodiment, the flange  218  may have a step like configuration at an outer surface and/or an inner surface of the flange  218 . For example, the step provided on the outer surface may be utilized for securing the flange  218  to the flange clamp  220 . The step provided on the inner surface of the flange  218  may be used for guiding the pipe  206  inside the flange  218 . The flange  218  may be welded or brazed to the pipe  206 . In one embodiment, as shown in the accompanying figures, the flange clamp  220  may have a two piece design. The two halves of the flange clamp  220  may surround the flange  218  of the pipe  206  when assembled. Each of the two halves includes holes  230  for receiving mechanical fasteners to attach the pipe  206  to the outlet port  212  of the hydraulic tank  208  for fluid communication between the hydraulic tank  208  and the pump  204 . The sealing ring  224  may be used to seal the leakage of the fluid. 
     The present disclosure relates to a valve  302  associated with the hydraulic tank  208 . The valve  302  is positioned within the outlet port  212  of the hydraulic tank  208 . As shown in  FIG. 3 , the valve  302  includes a main body  304  and an end cap  306 . The main body  304  and the end cap  306  may be manufactured from any metal known in the art. The main body  304  includes a first section  308  and a second section  310 . The first section  308  of the main body  304  has a solid configuration. The first section  308  may define a shoulder  312  formed by a projection positioned circumferentially along an outer surface  316  of the first section  308 . Further, one end of the first section  308  may have a tapered configuration to receive and contact with a spring  318 . A spring force of the spring  318  may actuate the valve  302 . The shoulder  312  may serve as an end stop for the spring  318  during operation of the valve  302 . More particularly, during the operation of the valve  302 , the spring force from the spring  318  may be transferred to the main body  304  through the shoulder  312  provided on the first section  308  of the valve  302 . 
     The second section  310  has a hollow configuration. The second section  310  extends from the first section  308 . A window  320  is defined on a surface of the second section  310  of the main body  304 . The window  320  is positioned towards an end of the second section  310  which is extended from the first section  308  of the main body  304 . The window  320  may selectively allow the fluid from the hydraulic tank  208  to enter into the main body  304  of the valve  302 , based on a position of the window  320  within the outlet port  212  of the hydraulic tank  208 . In one embodiment, a support structure  324  may be incorporated within the window  320  for rigidly attaching the first section  308  to the second section  310  of the main body  304 . Opening and closing of the valve  302  will be described in detail in connection with  FIGS. 4 ,  5  and  6 . In one embodiment, an outer surface  326  of the second section  310  of the main body  304  may include flat portions  328  defined for holding and positioning the main body  304  during the assembly of the valve  302 . These flat portions  328  are partially defined on the outer surface  326  of the second section  310  of the main body  304 . 
     The end cap  306  may be received into an end  330  of the second section  310  distal from the end connecting the first and second sections  308 ,  310  of the main body  304 . The end cap  306  has a hollow configuration. An outer surface  332  of the end cap  306  contains a plurality of threads  334  corresponding to a plurality of threads  336  provided on an inner surface  338  of the second section  310  of the main body  304 . The plurality of threads  334 ,  336  may be of different types like, for example, triangular threads, square threads, trapezoidal threads, and buttress threads for allowing the coupling of the end cap  306  and the second section  310 . The end cap  306  includes a flange  340  extending circumferentially from a distal end  342  of the end cap  306 . An outer surface  344  of the flange  340  of the end cap  306  has a flat portion  346  defined for holding and positioning the end cap  306  during the assembly of the valve  302 . An outer face  348  of the flange  340  may come in contact with the flange  218  of the pipe  206  when the pipe  206  is connected to the hydraulic tank  208 . In one embodiment, a groove (not shown) may be provided on the outer face  348  of the flange  340  for receiving the sealing ring  224  positioned between the flange  218  of the pipe  206  and the flange  340  of the valve  302 . The sealing ring  224  may prevent leakage of the fluid between the pipe  206  and the hydraulic tank  208 . 
       FIGS. 4 and 5  show the valve  302  in an open position. The valve  302  is in the open position when the pipe  206  is connected to the hydraulic tank  208  for drawing the fluid out of the hydraulic tank  208 , through the valve  302  positioned within the outlet port  212  of the hydraulic tank  208  and into the pipe  206  by the suction effect of the pump  204 . Arrows in  FIG. 4  show a direction of the fluid flow. The pipe  206  is not shown in the cutaway section of  FIG. 5  merely for the purpose of clarity.  FIG. 6  shows the valve  302  in the closed position. 
     An internal wall  402  may be provided within the hydraulic tank  208  and a plate  404  is attached to a portion of the internal wall  402 . The plate  404  may be attached to the internal wall  402  by using any known mechanical fasteners. The plate  404  is positioned behind the spring  318  of the valve  302  for providing a resting surface for the spring  318  to compress against when the valve  302  is in the open position. As shown in the accompanying figures, the outlet port  212  is situated on a side wall  410  of the hydraulic tank  208 , such that a major portion of the outlet port  212  lies within the hydraulic tank  208 . The outlet port  212  includes a channel  412  for receiving the valve  302  and guiding a movement of the valve  302  therein. An outer surface  414  of the outlet port  212  includes holes  502  (See  FIG. 5 ) for receiving mechanical fasteners to connect the pipe  206  to the hydraulic tank  208 . 
     As is clearly visible in  FIGS. 4 ,  5 ,  6 , an internal chamber  418  may be defined within the hydraulic tank  208  and surrounding the valve  302 , the internal chamber  418  is configured to be flooded with the fluid flowing out through an aperture  420  provided within the hydraulic tank  208 . The valve  302  is configured to selectively receive the fluid flow from the hydraulic tank  208  into the main body  304  based on the open position of the valve  302  with respect to the hydraulic tank  208  (as depicted in  FIGS. 4 and 5 ). When the pipe  206  is attached to the outlet port  212 , the flange clamp  220  may be bolted to the outlet port  212  of the hydraulic tank  208 . The flange  218  of the pipe  206  drives the valve  302  into the internal chamber  418  enabling the valve  302  to be in the open position. When in the open position, the valve  302  is positioned partly within the outlet port  212  and partly within the internal chamber  418  of the hydraulic tank  208 . The flange  218  of the end cap  306  rests in a step  424  provided in the outlet port  212  for holding the valve  302  within the outlet port  212 . 
     The window  320  is positioned within the internal chamber  418  in such a manner that the fluid may be received into the second section  310 . Referring to  FIG. 4 , the fluid flows from the second section  310  to the pump  204  through a passage created by the second section  310 , the end cap  306  and the pipe  206 . In the open position, the spring  318  may remain compressed against the plate  404  attached to the internal wall  402 . In one embodiment, a sealing ring  422  may be provided between the outer surface  326  of the valve  302  and the outlet port  212  to prevent leakage of the fluid. 
     Referring now to  FIG. 6 , the closed position of the valve  302  will be explained. The valve  302  is configured to disconnect the fluid flow from the hydraulic tank  208  into the main body  304  when the pipe  206  is disconnected from the valve  302 . More particularly, when the flange clamp  220  is removed from the outlet port  212 , the spring  318  may exert the spring force on the shoulder  312  of the first section  308  of the main body  304  of the valve  302 , causing the valve  302  to move in an outward direction with respect to the side wall  410  of the hydraulic tank  208 . When in the closed position, the valve  302  is positioned partially within the hydraulic tank  208  and partially outside of the hydraulic tank  208 . The window  320  is positioned within and covered by the outlet port  212  such that the fluid flow is prevented from entering into the second section  310 . This allows for sealing of the hydraulic tank  208  on disconnection of the pipe  206 . The shoulder  312  provided in the first section  308  of the valve  302  may come in contact with an inner wall  602  of the outlet port  212  thereby restricting the outward movement of the valve  302  within the outlet port  212  of the hydraulic tank  208 . The sealing ring  422  provided between the outer surface  316  of the first section  308  of the valve  302  and the channel  412  of the outlet port  212  may prevent the leakage of the fluid when the valve  302  is in the closed position. 
     INDUSTRIAL APPLICABILITY  
     Known hydraulic tank designs may leak when the pipe is disconnected from the hydraulic tank during servicing. The valve  302  provided in the present disclosure is configured to automatically seal the hydraulic tank  208  when the pipe  206  is disconnected from the hydraulic tank  208 . This may prevent the hydraulic fluid from spilling out of the hydraulic tank  208 . The valve  302  may provide a simplistic and cost effective solution. A person of ordinary skill in the art will appreciate that the valve  302  disclosed herein may be utilized in connection with a tank present on any machine  100  and is not limited to the application disclosed herein. 
     While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed machines, systems and methods without departing from the spirit and scope of what is disclosed. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof.