Abstract:
A male coupling half includes a male valve and a male body and the female coupling half includes a female valve and an inner body. The inner body is slidingly movable with respect to a housing or manifold. The female coupling half further includes a valve seated against a dump valve body which relieves pressure in the female half of the coupling to enable easy connection of the coupling halves. The male and female valves are locked in their open positions when the coupling halves are fully connected and the female half is pressurized which prevents reverse flow checking in either flow direction. During the disconnection process the male valve is closed before the coupling halves are separated which traps pressure in the male coupling half.

Description:
FIELD OF THE INVENTION  
       [0001]     The invention is in the field of couplings which may be used on agricultural, construction or other equipment.  
       BACKGROUND OF THE INVENTION  
       [0002]     There is a need for couplings to communicate hydraulic fluid to and from tractor mounted hydraulic power sources. There is also a need to communicate hydraulic fluid to and from agricultural or construction implements. A directional valve downstream from the power source controls the direction of the fluid in the hydraulic lines and, hence, the direction of the implement. Interposed between the directional valve and the load are a manifold and shut off valves. Typically, female coupling halves are carried in the manifold and male coupling halves are affixed to hydraulic lines leading to and from the implement. Use of a manifold is optional and female coupling halves may be mounted directly on the tractor or other device. It is therefore necessary to provide a coupling having valves which remain open and stable as the flow direction is reversed and which will not result in the valves closing upon reversal of flow and unintentionally and undesirably preventing flow (i.e., flow checking).  
         [0003]     When an implement is disconnected (uncoupled) from the manifold, it is desirable to maintain implement in a safe position by trapping fluid under pressure in the hydraulic lines between the male half of the coupling and the implement. The trapped fluid enables safe positioning of the implement until its next use. Sunshine and/or ambient heating further raise the pressure in the hydraulic lines leading to the implement making it difficult to connect (couple) the male coupling half into the female coupling half of the manifold for continued operation of the implement. When an implement is uncoupled from the manifold, fluid is also trapped between the female half of the coupling and a shut off valve interposed between the manifold and the directional control valve. Sunshine and/or ambient heating tend to increase the pressure of hydraulic fluid in the hydraulic lines and in the coupling making it difficult to couple the halves of the coupling together.  
         [0004]     In some applications, shut off valves are used to intentionally trap fluid between the shut off valve and the load when the load remains connected so as to maintain the safe positioning of the implement. The shutoff valves or their functional equivalent may be integral with the directional valve. In this instance too, sunshine and/or ambient heating tend to increase the pressure of hydraulic fluid in the hydraulic lines and in the coupling.  
         [0005]     It is desirable to provide a coupling which makes disconnection of the coupling halves easier and reduces or eliminates spillage.  
         [0006]     It is desirable to provide a coupling which enables the male half of the coupling to close prior to disconnection of the coupling so as to minimize spillage and so as to trap pressure in the male coupling half and the hydraulic line leading to the implement.  
         [0007]     It is desirable that the coupling halves be capable of connection under pressure, that is, with pressure applied to both halves of the coupling. It is further desirable that pressure be reduced or eliminated in the female half of the coupling to facilitate coupling.  
         [0008]     U.S. Pat. No. 5,937,899 to Zeiber discloses a female cartridge which is retained within a manifold. Axial and radial vent valves are disclosed. The &#39;899 patent provides a male half of the coupling which pushes the inner body of the pressurized female half of the coupling (which includes a pressurized chamber between a piston and a relief valve positioning member) causing the positioning member to be displaced in a leftward or rearward direction which causes the venting of the female member. The male half of the coupling pulls the inner body of the female half of the coupling rightwardly or forwardly which causes the venting of the female member. The venting occurs when the male and female halves of the coupling are connected or disconnected.  
         [0009]     U.S. Pat. No. 5,709,243 to Wells et al. discloses a low spill female coupling. A valve having an enlarged head is adapted to receive a male valve from the male half of the coupling such that the valves remain closed until respective parts thereof are brought into contact with each other so as to minimize spillage.  
         [0010]     U.S. Pat. No. 6,095,190 to Wilcox et al. discloses a female coupling half having internal pressure relief. The female half has three valves: a main valve, a relief valve and a sliding sleeve valve. The relief valve is a ball and seats against an elastomeric seal mounted on the back side of the main valve. A push pin having flat edges operates the relief valve.  
         [0011]     U.S. Pat. No. 4,077,433 to Maldavs illustrates a piston valve arrangement with a passageway through the valve to assist in assuring that the male ball valve remains open in high flow conditions from the male to the female. U.S. Pat. No. 4,881,573 to Durant illustrates a coupler having two poppet valves. The first poppet engages a ball check valve formed in the male coupling and the second poppet is actuated by a manually operated cam. A passageway exists in the piston to allow fluid to be vented or to pressurize the female valve.  
         [0012]     U.S. Pat. No. 4,598,896 to Maldavs illustrates a coupler having a spool and a port within the spool. An annular seal is fixedly positioned about the port in the spool. The spool is slidable with respect to the seal which enables pressure to be relieved in the female during coupling and uncoupling with the male. U.S. Pat. No. 4,303,098 to Shindelar discloses a coupler having a female half which includes a female valve having an elongated stem for engaging the male half. The female half of the coupling is vented by a pivotable cam which moves the inner member of the female half to release its locking means and then opens a poppet valve to open the outlet port.  
         [0013]     U.S. Pat. No. 4,249,572 to Shindelar et al. discloses a female half which is self-relieving. The female half includes dual poppet valves which are linked together. One of the poppet valves vents the female half of the coupling when the male and female valves are disengaged and uncoupled.  
         [0014]     U.S. Pat. No. 5,730,185 to Wilkins et al. discloses a coupling wherein certain positions of the adaptor allow the venting of the dispenser half and the receptacle half. Venting is prohibited by the movement of seals relative to ports and passageways.  
         [0015]     U.S. Pat. No. 3,730,221 to Vik provides an exterior vent valve.  
         [0016]     U.S. Pat. No. 4,745,948 to Wilcox et al. discloses a coupling device which utilizes locking detents which lock a stem against the male valve which prevents reverse flow checking.  
       SUMMARY OF THE INVENTION  
       [0017]     A female coupling half for use with a male coupling half is disclosed. The male coupling half includes a male valve and a male body. The female coupling half includes an outer body, a housing, an inner body and a female valve. The inner body is slidingly movable with respect to the housing between a first position and a second relief position. The housing resides partially within the outer body forming an annular passageway therebetween.  
         [0018]     Another embodiment of the invention employs a female coupling half which includes a cartridge retained within a manifold. In this embodiment, flow through the female coupler half is radially directed to a port in the manifold.  
         [0019]     In both embodiments, an inner body adaptor is affixed to the inner body. A dump valve body and lock piston slidingly engage the inner body adaptor. A dump valve (relief valve) is seated against the dump valve body. A valve lock shaft is slidingly engageable within the lock piston. During connection of the coupling halves under pressure, the female valve is affixed to the valve lock shaft and movable therewith between a first position and a relief position. The male body engages the inner body member and the male valve engages the female valve urging them from their first positions to other positions upon insertion of the male coupling half into the female coupling half.  
         [0020]     During connection of the coupling halves under pressure, the dump valve moves with the inner body member actuating the dump valve relieving pressure within the female coupler half. Before coupling and during venting, the valve lock shaft and the lock piston are releaseably secured to one another. As coupling begins and venting occurs the male body urges the inner body of the female coupling half leftwardly and carries the valve dump body, the valve lock piston, the sliding sleeve, the retainer and the valve lock shaft with it. Detents carried by the inner body engage the male body and the inner body member is urged leftwardly. At this time the male valve remains closed and has not yet engaged the female valve. Further, at this time the male body has not yet engaged the retainer of the female coupling half.  
         [0021]     Coupling continues further by urging the male half of the coupling further into the female half of the coupling such that the body of the male first engages the retainer followed by the male valve engaging the female valve. Since the body of the male engages the retainer slightly in time before the male valve engages the female valve the retainer and seal carried by the retainer separate slightly from the lip of the female valve. This enables subsequent repressurization of the female coupler to open the male valve and to further open the female valve. As the coupling progresses, the female valve and valve lock shaft are driven rearwardly causing detents carried in the lock piston to exit a circumferential recess in the valve lock shaft. A lock sleeve is positioned against a snap ring secured in the sliding sleeve by a spring operable between a shoulder on the sliding sleeve and the lock sleeve. As the retainer is engaged by the male body member, the sliding sleeve of the female coupler half is urged leftwardly which, in turn, urges the lock sleeve leftwardly through the spring operable between the lock sleeve and the sliding sleeve. When the coupling is disconnected, the lock sleeve is spaced apart from the detents carried in the lock piston. This allows for the detents to be displaced from the recess in the valve lock shaft before the lock sleeve drives the detents and the lock piston leftwardly. Therefore, as the male body engages the retainer followed by the the male valve engaging the female valve, the sliding sleeve, the valve lock shaft and the lock sleeve all begin to move leftwardly while the coupling is vented. The movement of the lock piston is delayed, however, until the lock sleeve drives it leftwardly.  
         [0022]     Next, the force on the male coupling half (i.e., the force exerted by a human hand) is removed and the coupling is fully connected but the male valve remains closed until pressure is applied to the female coupling half. At this time the female valve is slightly open. As pressurization of the female coupling half begins pressure equalization of the male and female halves occurs. The male and female valves shift rightwardly until the valve lock shaft moves sufficiently rightwardly that the detents carried by the lock piston are urged radially inwardly to engage a circumferential recess in the valve lock shaft. The lock sleeve secures the detents in the recess while the coupling is engaged ensuring that the male and female valves in the coupling remain open during use of the coupling. This prevents unwanted reverse flow checking.  
         [0023]     To disconnect the pressurized coupling, the male coupling half is urged leftwardly into the female coupling half to vent the female half of the coupling. As the male coupling half is urged leftwardly, pressure in the coupling urges the coupling halves apart and acts upon the interface between the body of the male coupling half and the inner body member locking the detents carried by the inner body member into engagement with the land on the locking sleeve. Once pressure is vented from the coupling, the male body no longer applies force on the detents carried by the inner body member allowing them to move radially inwardly and out of frictional engagement with the land on the lock sleeve. A spring is operable between the vent valve and the valve lock shaft. The spring is compressed as the vent valve engages the housing or, in another embodiment, the manifold body. As pressure is relieved by the vent valve from the coupled condition, pressure is first reduced in the piston chamber formed by the lock piston, the valve dump body and the inner body adaptor. The piston chamber is separated from the remainder of the female coupling half by a resistance in the form of an annular passageway about the stem of the vent valve and the inside diameter of the valve lock shaft. An additional resistance in the form of a vent passageway is formed in the vent lock shaft. These resistances isolate the chamber from the fluid pressure external to the valve lock shaft. In particular, a seal between the lock piston and the inner body adaptor and a seal between the valve lock shaft and the lock piston experience relatively lower pressure as the chamber is vented as compared to seals which reside externally to the valve lock shaft. Specifically, a seal which operates between the valve lock shaft and the lock piston and a seal which operates between the sliding sleeve and the lock piston experience relatively high pressure. The differential pressure on the aforementioned seals results in shuttling the valve lock shaft leftwardly enabling the male and female valves to seat prior to disconnection. At this time the male valve engages the female valve such that no space is created therebetween so as to minimize fluid spillage on disconnection. The coupling halves are then pulled apart and separated with pressure trapped within the male coupling half so as to enable the safe positioning of an implement.  
         [0024]     If the male and female coupling halves are not pressurized the male coupling half is inserted into the female coupling half urging the inner body member leftwardly. The inner body adaptor, the valve dump body, and the relief valve are all moved leftwardly under the urging of the male body against the inner body member of the female valve. The male valve engages the female valve as coupling progresses. The relief valve engages the bore of the manifold and the spring operable between the relief valve and the valve lock shaft overcomes the spring operable between the male valve and the canister in the male valve opening the male valve. The female valve opens simultaneously with the opening of the male valve.  
         [0025]     The coupling may be easily separated if it is not under pressure as the coupling halves are not pressure locked together. Separation in the absence of pressure is accomplished by pulling the male body member and valve away from the female half of the coupling. A spring operable between the inner body adapter and the sliding sleeve urges the sliding sleeve and retainer rightwardly. As the male valve is withdrawn from the female valve, a spring operable between the canister of the male coupling half and the male seal retainer urge the male valve to its closed position.  
         [0026]     It is an object of the present invention to provide a coupling which is a low spill coupling on connection and disconnection.  
         [0027]     It is a further object of the present invention to provide a coupling which may be easily connected with pressure applied within the female coupling half and/or the male coupling half.  
         [0028]     It is a further object of the present invention to provide a coupling having a female coupling half which is manifold mounted.  
         [0029]     It is a further object of the present invention to provide a coupling which locks the valves of the male and female coupling halves in the open position and which prevents reverse flow checking of the male and female valves in the event that the direction of the flow is reversed or changes.  
         [0030]     It is a further object of the present invention to provide a coupling which opens and locks the male and female valves of the coupling halves in the open position by applying pressure to the female half of the coupling once it is coupled together with the male.  
         [0031]     It is a further object of the present invention to provide a coupling which enables the male coupling half to trap pressure therein upon disconnection of the coupling.  
         [0032]     These and other objects of the invention will be better understood when the Brief Description of the Drawings, Description of the Invention and Claims set forth below are read. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0033]      FIG. 1  is a cross-sectional view of a manifold illustrating a female half of the coupling inserted therein.  
         [0034]      FIG. 1A  is a cross-sectional view of a manifold illustrating the male half of the coupling entering the female half of the coupling which is being vented.  
         [0035]      FIG. 1B  is a cross-sectional view of a manifold illustrating the male half of the coupling fully inserted into the female half of the coupling which is being vented.  
         [0036]      FIG. 1C  is a cross-sectional view of a manifold illustrating the coupling fully connected with the male valve of the male half of the coupling closed.  FIG. 1C  also illustrates the female valve off its seal, slightly open.  
         [0037]      FIG. 1D  is an enlargement of a portion of  FIG. 1C  illustrating the closed male valve and the slightly open female valve.  
         [0038]      FIG. 1E  is a cross-sectional view of the coupling with the female half pressurized, partially opening the male valve of the male coupling half.  
         [0039]      FIG. 1F  is a cross-sectional view of the coupling with the male and female valves in the fully open position.  
         [0040]      FIG. 1G  is a cross-sectional view of the coupling in the process of disconnection with pressure being relieved from the female half of the coupling and the male and female halves of the coupling shifting leftwardly toward the closed position.  
         [0041]      FIG. 1H  is an enlargement of a portion of  FIG. 1 .  
         [0042]      FIG. 1I  is a cross-sectional view of the coupling wherein the uncoupling process has proceeded further with the male and female valves in the closed position.  
         [0043]      FIG. 2  is a cross-sectional view of the second embodiment of the female half of the coupling illustrated disconnected from the male half of the coupling.  
         [0044]      FIG. 3  is a cross-sectional view of the second embodiment of the female half of the coupling illustrated connected (coupled) with the male half of the coupling.  
         [0045]      FIG. 4  is a cross-sectional view of the second embodiment of the female half of the coupling illustrated with the valves in the closed position and the female coupling half vented.  
         [0046]      FIG. 4A  is an enlargement of a portion of  FIG. 4 .  
         [0047]      FIG. 5  is a cross-sectional view of the second embodiment of the female half of the coupling illustrated with pressure applied to the female half of the coupling to open the male and female valves.  
         [0048]      FIG. 6  is a cross-sectional view of the housing.  
         [0049]      FIG. 6A  is a left side view of the housing.  
         [0050]      FIG. 6B  is a right side view of the housing.  
         [0051]      FIG. 7  is a schematic of one application of the first embodiment of the present invention.  
         [0052]     A better understanding of the drawings and the invention will be had when reference is made to the Description of the Invention and Claims which follow hereinbelow. 
     
    
     DESCRIPTION OF THE INVENTION  
       [0053]      FIG. 1  is a cross-sectional view  100  of manifold  101  with a female half of the coupling inserted therein.  FIGS. 1-1I  illustrate a first embodiment of the invention which includes a manifold mounted female coupling half.  FIGS. 2-6B  illustrate a second embodiment of the invention.  
         [0054]      FIG. 1  illustrates a cartridge of female coupling elements carried in a manifold  101 . In  FIG. 1 , the female coupling half is illustrated. Conduit  102  leads to a hydraulic energy source. Vent conduit  103  communicates with bore  104  in the manifold  101 . Spring  105  is operable between manifold body  101  and inner body  110 . As the male body engages the inner body  110  it is urged leftwardly against the force of spring  105 . See  FIG. 1A . Once inner body  110  is moved far enough leftwardly, relief valve  121  engages indentation  166  in bore  104 . Relief valve  121  includes pin  164  having end  165  which engages indentation  166  in the bore  104 . Instead of indentation  165 , a flat surface terminating the bore  104  may be used.  
         [0055]     Valve  121 , a relief valve, operates against seat  160  on valve dump body  119 . Valve lock shaft  122  is hollow and stem  112  of valve  121  slides within valve lock shaft  122 . There is a very small clearance  132  between stem  112  and the inside diameter of valve lock shaft  122 . Spring  135  is operable between valve lock shaft  122  and valve  121  urging valve  121  to engage seat  160  of valve dump body  119 . See  FIG. 1A .  
         [0056]     Valve dump body  119  is slidingly engageable within inner body adaptor  118  which is, in turn, affixed to inner body  110 . Lock piston  120  is also slidingly engageable within inner body adaptor  118 . Spring  133  urges the dump valve body  119  and lock piston  120  apart. Lock piston  120  is restrained in its rightward movement by a shoulder on the inner body adaptor  118  and dump valve body  119  is restrained in its leftward movement by snap ring  134  in a groove in the inner body adaptor  118 . Inner body adaptor  118  is threaded  123  to the inner body  110 .  
         [0057]     Still referring to  FIG. 1 , female valve  124  is threaded  125  to valve lock shaft  122  and is movable therewith. Sliding sleeve  117  resides generally between the inner body member  110  and inner body member adaptor  118  and the valve lock shaft  122 . Retainer  116  is threaded to the sliding sleeve  117  and retains seal  151  which abuts and seals lip  154  of valve  124  as illustrated in  FIG. 1 . Seal  151  is preferably a polymeric nitrile seal.  FIGS. 1A and 1B  illustrate male body  301  engaging retainer  116  separating seal  151  away from lip  154  which enables the repositioning of valves  124 ,  302  to their open position upon pressurization of the female half of the coupling.  
         [0058]     Spring  143  is operable between inner body adaptor  118  and a shoulder on sliding sleeve  117 . Sleeve  117  is restrained in its movement in the rightward direction when viewing  FIG. 1  by the inner body  110 . Lock sleeve  168  resides generally between sleeve  117  and lock piston  120 . Spring  167  is operable between a shoulder on sliding sleeve  117  and lock sleeve  168 . Leftward movement (viewing  FIG. 1 ) of lock sleeve  168  is prevented by snap ring  144 .  
         [0059]     Lock piston  120  includes a plurality of apertures  139 A in which reside detents  139 . As viewed in  FIG. 1 , some of the detents  139  are illustrated sitting in recess  155  and some of the detents  139  are shown out of the recess  155  due to gravity. Valve lock shaft  122 , under certain conditions discussed below, is free to move axially rearwardly (leftwardly) upon the urging of the male half of the coupling which is not shown in  FIG. 1 . Valve lock shaft  122  includes hollow sections or passageways  131 ,  126 . Vent passageway  127  communicates with apertures  128  in the sliding sleeve  117  which in turn communicate with circumferentially spaced apertures  130  in the inner body  110 . Passageway  129  communicates with conduit  102  to supply or return fluid depending on the position of the directional valve. Seals  141 ,  148  seal the inner body  110  with respect to the manifold  101  and the seal retainer  109 , respectively. Seal  147  prevents leakage between the seal retainer  109  and the manifold  101 .  
         [0060]     Adaptor  107  is threaded  106  into manifold  101 . Locking sleeve  108  is biased by spring  114  to a forward position as illustrated in  FIG. 1 . Locking detents  113  carried in apertures  159  of inner body  110  are secured in position by land  111  on locking sleeve  108 .  
         [0061]     Still referring to  FIG. 1 , entrance seal  150  prevents leakage between the male body and inner body  110  upon entrance of the male body into the female coupling half. Seal  149  prevents leakage between the interface between retainer  116  and inner body  110 . Seal  142  prevents leakage between the inner body adaptor  118  and inner body  110 . Seal  140  prevents leakage between the sliding sleeve  117  and the inner body adaptor  118 . Seals  138 ,  146  prevent leakage between the valve lock shaft  122  and the lock piston  120 . Seal  136  prevents leakage valve dump body  119  and inner body adaptor  118 . Seal  137  prevents leakage between lock piston  120  and inner body adaptor  118 . Seal  145  prevents leakage between the sliding sleeve  117  and lock piston  120 .  
         [0062]     Valve  124  includes an opening  152  having a cylindrical bore  153  for reception of the male valve. Lip  154  engages nitrile seal  151  as illustrated in  FIG. 1 .  
         [0063]     Atmospheric vent  175  resides between sliding sleeve  117  and inner body adaptor  118 . As sliding sleeve  117  is moved toward the inner body adaptor against the bias of spring  143 , air is evacuated to vent  103 . Air escapes along passageway  175 A as illustrated in  FIG. 1A  and along the interface between the inner body  110  and the adaptor  118 .  
         [0064]      FIG. 1A  is a cross-sectional view  100 A of a manifold illustrating the male half of the coupling entering the female half of the coupling. Body  301  of the male coupling half engages the detents  113  carried in the inner body member  110  and drives the inner body member  110  leftwardly as illustrated in  FIG. 1A . Relief (dump) valve  121  is carried by the body adaptor  118  affixed to the inner body member  110 , the dump valve body  119  and the lock piston  120 . Spring  135  biases relief valve  121  against a seat  160  on the dump valve body  119 . As the inner body member  110  is urged leftwardly, pin  164  of relief valve  121  engages the indentation  166  in bore  104  of the manifold which vents the female half of the coupling. As viewed in  FIG. 1A , venting occurs prior to the male valve  302  engaging the female valve  124  and prior to the male body  301  engaging the retainer  116 .  
         [0065]     Still referring to  FIG. 1A , it will be observed that prior to engagement of the male and female valves that some of the detents  139  carried by apertures  139 A in the lock piston  122  reside loosely in recess  155 . Other detents  139  are not in recess  155  because gravity causes them to exit recess  155 .  
         [0066]      FIG. 1B  is a cross-sectional view  100 B of a manifold illustrating the male half of the coupling fully inserted into the female half of the coupling. Detents  113  are shown engaging a circumferential recess  305  in male body  301  in  FIG. 1B . Referring to  FIG. 1B , male and female valves  124 ,  302  are in engagement and valve lock shaft  122  is driven rearwardly such that the detents  139  exit recess  155  and ride on the exterior of valve lock shaft  122 . Lock piston  120  moves leftwardly by engagement of lock sleeve  168  with detents  139  carried in apertures  139 A in lock piston  120 . Spring  167  is operable between lock sleeve  168  and sliding sleeve  117 . Lock sleeve  168  is driven by spring  167  which, in turn, is driven by sliding sleeve  117 . As sliding sleeve  117  is driven leftwardly, air in volume  175  ( FIG. 1 ) exits through passageway  175 A and past the interface between the inner body member  110  and the body adaptor  118 .  
         [0067]     Still referring to  FIG. 1B , lip  154  of valve  124  does not engage seal  151 . See also  FIGS. 1C and 1D  which illustrate a gap  156  between the inner portion  158  of seal  151  and lip  154  of valve  124 . In  FIG. 1B , inner body member  110  is shown fully leftwardly with springs  128 ,  133 ,  135  and  143  compressed. In  FIG. 1B  the female coupling is vented and male body  301  has forced retainer  116  and seal  151  away from lip  154  of female valve  124 . This positional relationship of the retainer  116  and seal  151  with respect to lip  154  is fixed and maintained by body  301  engaging locking detents  113  as illustrated in  FIG. 1C . Even after the force applied by hand to body  301  is released, land  111  in sleeve  108  keeps retainer  116  and seal  151  slightly spaced apart from lip  154  of valve  124 .  
         [0068]      FIG. 1C  is a cross-sectional view  100 C of a manifold illustrating the coupling fully connected with the male valve  302  of the male half of the coupling closed. Female valve  124  is open as viewed in  FIG. 1D , an enlargement of a portion of  FIG. 1C . Referring to  FIG. 1D , female valve  124  is illustrated as spaced apart from seal  151  and slightly open. As illustrated in  FIGS. 1C and 1D , the female half of the coupling is ready for pressurization against a closed and pressurized male valve  302 . The opening of male valve  302  is facilitated by pressurizing of the female half of the coupling and the volume  156 . Volume  156  leads to the interface  184  between valve  302  and male body  301  exposing seal  183 . When the female half is pressurized the entire inner surface  154 A of the lip  154  of the valve  124  is subjected to pressure as is a portion  302 A of the male valve, the interface  184  between valve  302  and male body  301 , and seal  183 . See,  FIG. 1D .  
         [0069]      FIG. 1E  is a cross-sectional view  100 E of the coupling with the female half pressurized, partially opening the male valve  302  of the male coupling half and further opening the female valve  124 . Reference numeral  173  represents pressure applied to the female half enabling the opening of the male half under pressure. It will be noticed in  FIGS. 1C and 1E  that the valve lock shaft is not locked with respect to the lock piston. As pressure is applied to the female half, and, more specifically, as pressure is applied to surface  179  of valve  124  (the inner surface), the interior rightward looking surfaces of the inner body  110 , sliding sleeve  117 , and lip  154 A of valve  124  urge the valve  124  and the valve lock shaft  122  rightwardly opening the valves  124 ,  302  until balls  139  enter recess  155  as illustrated in  FIG. 1F . Additionally, as pressure is applied to seals  138  and  146 , the area of seal  138  and the rightward looking area of valve lock shaft  122  is slightly larger than the area of seal  146  and the leftward looking area of valve lock shaft  122  which contributes to the rightward movement of valve lock shaft  122  and valve  124 . Balls  139  are urged into recess  155  by spring  167  and lock sleeve  168 . Spring  167  is under compression as pressure is applied to the female half. Spring  167  secures lock sleeve  168  in engagement with balls  139  so that they may not be removed from recess  155 .  
         [0070]      FIG. 1F  is a cross-sectional view  100 F of the coupling with the male and female valves  124 ,  302  in the fully open position. Reference numeral  172  indicates bidirectional flow through the fully open coupling.  
         [0071]     If the male and female coupling halves are not pressurized, the male coupling half is inserted into the female coupling half urging the inner body member  110  leftwardly. The inner body adaptor  118 , the valve dump body  119 , and the relief valve  121  are all moved leftwardly under the urging of the male body  301  against the inner body member  110  of the female half. The male valve  302  engages the female valve  124  as coupling progresses. The relief valve  121  engages the bore of the manifold and the spring  135  operable between the relief valve  121  and the valve lock shaft  122  overcomes the spring  180  operable between the male valve  302  and the canister  181  in the male coupling half opening the male valve  302 . The female valve  124  opens simultaneously with the opening of the male valve  302 .  
         [0072]     The coupling may be easily separated if it is not under pressure as the coupling halves are not pressure locked together. Separation in the absence of pressure is accomplished by pulling the male body member  301  and male valve  302  away from the female half of the coupling. A spring  143  operable between the inner body adapter  118  and the sliding sleeve  117  urges the sliding sleeve  117  and retainer  116  rightwardly. As the male valve  302  is withdrawn from the female valve  124 , a spring  180  operable between a canister  181  and the male seal retainer  182  urge the male valve  302  to its closed position.  
         [0073]      FIG. 1G  is a cross-sectional view  100 G of the coupling in the process of disconnection with pressure being relieved from the female half of the coupling and the male and female valves  124 ,  302  of the coupling shifting toward the closed position. Still referring to  FIG. 1G  as pressure is relieved from the coupling by a person urging the male body  301  leftwardly, pressure is reduced in chamber  171  first followed by a reduction in pressure in the volumes defined by reference numerals  131  and  126 , followed by a reduction in pressure in volume  170 . To disconnect the pressurized coupling, the male coupling half is urged leftwardly into the female coupling half to vent the female half of the coupling. As the male coupling half is urged leftwardly, pressure in the coupling urges the coupling halves apart and acts upon the interface  185  between the body  301  of the male coupling half and the inner body  110  of the female coupling half locking the detents  113  carried by the inner body member into engagement with the land  111  on the locking sleeve  108 . Once pressure is vented from the coupling, the male body removes tension from the detents  113  carried by the inner body member allowing them to move radially inwardly and out of frictional engagement with the land  111  and apertures in the inner body. Referring to  FIG. 1H , an enlargement of a portion  FIG. 1G , reference numeral  132  illustrates a small circumferential gap around stem  112  and between valve lock stem  122 . Gap  132  is in effect an orifice or resistance which retards the flow of hydraulic fluid. Likewise, small passageway  127  is in effect an orifice or resistance which retards the flow of hydraulic fluid.  
         [0074]     Referring still to  FIGS. 1G and 1H , as valve  121  moves from its seat chamber  171  is vented and pressure on seals  137  and  138  is lowered which results in the leftward movement of lock piston  120  and valve lock shaft  122 . Relatively high pressure is applied to seals  145  and  146  which also tend to urge the valve lock piston and the valve lock shaft  122  leftwardly. Movement of the valve lock shaft  122  leftwardly enables closure of male valve  302  trapping pressure behind male valve  302 . This enables the safe positioning of an implement until its next use.  
         [0075]     The gaps  132  and the passageway  127  are resistances and the volume  170  of pressurized fluid is in effect a capacitance. When pressure is released from volume  171 , the reduction of pressure in volume  170  is reduced over a period of time and the decay of pressure in volume  170  is in effect somewhat analogous to the discharge of voltage across a capacitor. The pressure differential across the valve lock shaft shuttles the valve lock shaft leftwardly closing valve  302 .  
         [0076]      FIG. 1I  is a cross-sectional view  100 I of the coupling wherein the uncoupling process has proceeded further with the male  302  and female valves  124  in the closed position. In  FIG. 1I  there is no pressure on the female portion of the coupling and the male valve is closed with pressure trapped behind it. The coupling may now be pulled apart by hand. Instead of being operated by hand the male and female halves of the invention can be adapted to coupling mechanically without the use of a person&#39;s hand to provide the force necessary to vent, couple and decouple the coupling halves.  
         [0077]      FIGS. 2-6B  illustrate the second embodiment of the female half of the coupling. The inner body  110  and the inner body adaptor  118  and components residing therein are in effect a cartridge inserted within housing  280  or in the embodiment of  FIG. 1  they are inserted within the manifold  101  and seal retainer  109 . The elements of the cartridge have the same structure and function as described above in connection with  FIGS. 1-1I .  
         [0078]     In this embodiment, the female coupling half is rigidly mounted to an adaptor  262  by a threaded interconnection  287  between adaptor  262  and outer body  286 . Referring to  FIG. 2 , a vent passageway  270  is illustrated in housing  280  and leads to passageway  260  which leads to vent annulus  297  formed by vent gland  293  threaded  294  to housing  280 . Vent gland  293  is an elastomeric material. A vent  298  is threadably connected to vent gland  293 . Serrations  299  on the vent enable hose to be better secured to the vent. Retaining ring  295  secures vent gland  293  to adaptor  262 .  
         [0079]     Referring to  FIG. 2 , adaptor  207  is threaded to outer body  286  and retainer locking sleeve  108  against the force of spring  114 .  
         [0080]     Still referring to  FIG. 2 , seals  261  and  292  prevent leakage between housing  280  and adaptor  262 . Seal  290  prevents leakage between end portion  291  of adaptor  262  and outer body  286 .  
         [0081]     Still referring to  FIG. 2 , annulus  282  is formed between housing  280  and outer body  286 . Annulus  282  communicates with a plurality of ports/apertures  281  in housing  280 . Annulus  283  is formed between end portion  291  of adaptor  262  and housing  280 . A plurality of passageways  284  interconnect annulus  283  to bore  263  in adaptor  262 . Reference numeral  277  signifies a relief flow path for air residing in volume  175  as previously discussed above in connection with the first embodiment.  
         [0082]      FIG. 2  is a cross-sectional view  200  of the second embodiment of the female half of the coupling illustrated disconnected from the male half of the coupling. The connected position ( FIG. 3 ) of the inner body member  110  in relation to the housing  280  and the disconnected position ( FIG. 2 ) of the inner body member  110  in relation to the housing  280  are the same. Similarly, the connected position ( FIG. 3 ) and the disconnected ( FIG. 2 ) position of the female valve  124  are the same.  
         [0083]      FIG. 3  is a cross-sectional view  300  of the second embodiment of the female half of the coupling illustrated connected (coupled) with the male half of the coupling.  
         [0084]      FIG. 4  is a cross-sectional view  400  of the second embodiment of the female half of the coupling illustrated with the male valve in the closed position and the female valve partially open coupling half is being vented.  FIG. 4A  is an enlargement of a portion of  FIG. 4 . Reference numeral  401  represents the vent flow path of the second embodiment.  
         [0085]      FIG. 4  illustrates the position of the valve lock shaft  122  and the position of the inner body  110  (and inner body adaptor  118 ) moved rearwardly (leftwardly). Valve  121  is illustrated off seat  160  permitting the relief of pressure. Arrow  401  illustrates a relief flow path to atmospheric pressure. Passageway  270  in housing  280  is indicated in phantom. See  FIGS. 6 and 6 A for other views illustrating passageway  270 .  FIG. 4A  is an enlargement  400 A of a portion of  FIG. 4  illustrating flow arrow  401  and flow between dump valve stem  112  and valve lock shaft  122 .  
         [0086]      FIG. 5  is a cross-sectional view of the second embodiment of the female half of the coupling illustrated with pressure being applied to the female half of the coupling as indicated by reference numeral  501  to open valves  124  and  302 .  
         [0087]      FIG. 6  is a cross-sectional view of the housing  600  illustrating apertures  281 , passages  284  and vent passageway  270  in more detail.  FIG. 6A  is a left side view  600 A of the housing  280  and  FIG. 6B  is a right side view  600 B of the housing  280 .  
         [0088]      FIG. 7  is a schematic  700  representation of an application of the first embodiment of the present invention. Power source  701  is typically a hydraulic pump mounted on a tractor. Hydraulic fluid is pumped through a hydraulic line  711  to a directional valve  702  where it is directed through shut off valves  703 ,  704  in one or the other directions. Bidirectional arrows between the shut off valves and the manifold  705  indicate that the directional valve may direct fluid to or from a specific coupling mounted within the manifold  705 . Bidirectional lines  706 ,  707  indicate that the male coupling halves  708  may be connected and disconnected from the respective female coupling halves whose cartridges are mounted in the manifold as illustrated and described in connection with  FIGS. 1-1I  above. The load  710  may be run in either direction as dictated by the directional valve  702 . As stated previously it is desirable to maintain the safe position of the implement/load  710  while disconnecting the male coupling halves  708 ,  709  from the female coupling halves in the manifold  705  by retaining pressure on the male coupling halves. Still referring to  FIG. 7 , lines  714  and  715  are vent lines from the manifold for the relief of pressure to reservoir  713  at atmospheric pressure. Further, line  716  is a bypass line for directing fluid from the bidirectional valve  702  to the reservoir. Line  712  is a return line (pump suction) line to the power source.  
         [0089]     While the invention has been described herein by way of example and with particularity, those skilled in the art will readily recognize that changes and modifications may be made to the invention without departing from the spirit and scope of the appended claims.