FARM COUPLING

Abstract: A coupling comprising a male portion and a female portion wherein the female portion comprises: a housing, an inner body member positioned within the housing and slidable relative thereto, a relief valve positioning member, a piston residing intermediate the relief valve positioning member and the inner body member and slidable relative to the positioning member and the inner body member, and a valve. The housing includes a first port and a second port. The inner body member includes a port communicating with the first port of the housing. The relief valve positioning member includes a relief valve. The piston includes an interior, an exterior, and a passageway interconnecting the interior of the piston and the exterior of the piston. The valve slidably engages the piston and seats against the inner body member. The male portion of the coupling engages the inner body of the female portion. A chamber is formed between the piston and the relief valve positioning member which, when pressurized, results in the movement of the positioning member when the inner member is moved leftwardly during coupling with the male portion. Movement of the inner body of the female portion moves the relief valve positioning member axially away from the male member opening the relief valve and venting the female member through the second port of the housing of the female member.

Description: FARM COUPLING FIELD OF THE INVENTION This application claims the right of priority of prior filed United States Application Serial No. 60/037,571 filed February 10, 1997. The invention disclosed herein relates to couplings used on agricultural implements, namely, tractors. The female half of the coupling is typically mounted on the tractor. The female half of the coupling mates with a male half and fluid flows therethrough to power auxiliary equipment. The male half of the coupling is connected to a hose or other conduit which supplies auxiliary equipment. This invention is directed toward the enablement of easy coupling and uncoupling of the male and female halves. Both processes, coupling and uncoupling, occur when vent the vent valve of the instant invention relieves the internal pressure on the female valve. Easy uncoupling, with very little spillage occurs because the male valve closes against an unpressurized female valve. BACKGROUND OF THE INVENTION United States Patent 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. United States Patent 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. United States Patent No. 4,598,896 to Maldavs illustrates a coupler having a spool and a port within the pool. 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. United States Patent 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. U. S. Patent 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. None of the prior art, however, 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. Similarly, the male half of the coupling in the instant invention pulls the inner body of the female half of the coupling rightwardly or forwardly which causes the venting of the female member. Different embodiments of the venting mechanism are disclosed herein. Also, a manual venting mechanism is disclosed herein. The manual venting mechanism must be operated each time the coupling is made or broken. SUMMARY OF THE INVENTION It is an object of the present invention to provide a coupling which may be used on agricultural implements. Typically, the female half of the coupling is mounted on a tractor and pressurized hydraulic fluid is supplied thereto. The female coupling includes inlet and outlet ports. The inlet port is connected to a pressure source and the outlet port is connected to a sump or reservoir for recycling back to a pump. The female half of the coupling is capable of being joined with a male half of the coupling. The male half of the coupling is typically connected to an implement which does work of some kind. It is an object of the invention to provide a relief mechanism in the female half of the coupling such that pressure is relieved inside the female half of the coupling when the male half is being coupled or uncoupled to the female half. This enables easy coupling and uncoupling and mώimizes any fluid spillage. The female half of the coupling may or may not be pressurized in the uncoupled condition. The pressure source to the female half of the coupling is isolated when the coupling is disconnected. Sometimes, however, pressure is trapped between the isolation valves in the conduit leading to the inlet port and the female half of the coupling in the disconnected/uncoupled state. The male half of the coupling is typically pressurized as the pressure generated by the fluid is trapped within the coupling upon disconnection from the female half. It is an object of the instant invention to provide a vent valve in the female half of the coupling to relieve pressure within the female half of the coupling in two circumstances. The first circumstance is when the male half enters the pressurized female inner member. The inner body member is movable relative to the female outer body/housing. A threaded sleeve is threaded to the female body/housing. A vent valve resides in a relief valve positioning member. A spring resides intermediate a plug and the vent valve. The spring is compressed as the vent valve is moved along the varying contour of the sleeve. When the vent valve is depressed it allows fluid within the female half of the coupling to escape to the vent return passage. The vent return passage is at or near atmospheric pressure. The vent return passage can be connected to a reservoir for recycling the hydraulic fluid which is typically used in agricultural implements associated with tractors. In further describing the first circumstance of venting, the male member engages the inner body member and moves it leftwardly when viewing Figure 1. As inner body member moves leftwardly, the relief valve positioning member moves leftwardly relative to the sleeve which is fixed to the female body /housing. A pressurized chamber is formed between the piston and the relief valve positioning member. The relief valve positioning member is restrained from movement in one direction by a snap ring residing in a groove in the interior of the inner body member. As this leftward movement continues, the vent valve is depressed as it moves along the varying contour of the inner sleeve. This vents any fluid that may be inside the piston, the chamber and the inner body member . While this is happening, female valve is closed. Once the pressure is released inside the female half of the coupling, the valve may then open. The male half of the coupling is coupled to the female half through the interaction of the locking sleeve, springs, a washer and detent members or balls. The inlet pressure port supplies pressure to the coupling. A passageway through the inner body member leads to a passageway which leads around the female valve to the male member. The male valve abuts female valve in the coupled condition. In the second circumstance of venting, when the male member is retracted from the female member, the male member is pulled rightwardly when viewing Figure 1. As the male member is pulled rightwardly it brings with it the inner body member of the female member. The inner body member moves relative to the fixed body/housing. A snap ring resides in the inner body member and engages the relief valve positioning member and pulls it rightwardly. As the relief valve positioning member is pulled rightwardly, vent valve relieves the pressure along the interface of the valve positioning member and the sleeve. Fluid will continue to flow to the vent passage until the male valve closes and pressure is relieved from the chamber (sometimes referred to herein as the valve actuating pressure chamber) formed by the piston and relief valve positioning member. When the female member's valve closes under the urging of a spring, pressure is equalized within the valve actuating pressure chamber and the relief valve positioning member shuttles to the normal position closing off the flow to the vent. It will be observed that the vent valve has seals around it which prevent leakage. It is a further object of the present invention to provide a coupling whose female portion thereof includes a relief valve positioning member comprised of two portions. It is a further object of the present invention to provide a coupling whose female portion thereof includes a relief valve positioning member which includes at least one vent valve therein. It is a further object of the present invention to provide a coupling whose female portion thereof includes a relief valve positioning member which is positioned by an inner body member operated in combination with a spring, a valve and a piston. It is a further object of the present invention to provide a coupling which includes locking means which interact with the inner body member of the female coupling. A better understanding of the invention will be had when reference is made to the Brief Description of the Drawings, Description Of The Invention, and Claims which follow hereinbelow. BRIEF DESCRIPTION OF THE DRAWINGS Fig. l is a partial cross-sectional view of the male and female halves of the coupling in the coupled condition. Fig. 1 A is a view similar to that in Fig. 1 except that another embodiment employing two vent valves is illustrated. Fig. 2 is a cross-sectional view of the male half of the coupling. Fig. 3 is a partial cross-sectional view of the female half of the coupling in the uncoupled condition and with the female valve closed. Fig. 4 is a partial cross-sectional view of the female half of the coupling illustrating, among other things, a relief valve positioning member having two relief valves and a two piece venting assembly. Fig. 5 is an enlargement of the threaded relief valve positioning member illustrated in Fig. 4. Fig. 6 is a partial cross-sectional view of the male and female halves of the coupling in the coupled condition similar to Fig. 1 except the passageway interconnecting the inlet port to the interior of the female half of the coupling is in the valve instead of the piston. Fig. 7 is a view similar to Fig. 5 illustrating the vent valves off-center and to the right. Fig. 8 is a view similar to Fig. 5 illustrating the vent valves off-center and to the left. DESCRIPTION OF THE INVENTION Fig.1 is a partial cross-sectional view of the male and female halves of the coupling in the coupled condition. A coupling comprising a male portion 19' and a female portion 1' is disclosed. The female portion includes: a housing 1, an inner body member 12 positioned within the housing and slidable relative thereto, a relief valve positioning member 10 and a valve 2. A piston 3 resides intermediate the relief valve positioning member 10 and the inner body member 12 and is slidable relative to the positioning member and the inner body member. The housing includes a first port 4 and a second port 6. Port 4 is connected to a pump which supplies pressurized fluid to the female portion 1' of the coupling. Port 6 is a vent passage. The inner body member includes a port 24 communicating with the first port 4 of the housing 1. The relief valve positioning member 10 includes a relief valve 7, a plug 22 and a spring 11 operating between the plug 22 and the relief valve 7. The plug 22 is press fit into the relief valve positioning member 10. A passageway (port) 4 through the inner body member 12 leads to a passageway 25 which leads around the female valve to the male valve. See, Fig. 1. The piston 3 includes an interior 69, an exterior 70, and a passageway 21 interconnecting the interior 69 of the piston and the exterior 70 of the piston. The valve 2 slidably engages the piston and seats against the inner body member 12 when the coupling is disconnected. See Fig. 3. Spring 9 operates between the valve positioning member 10 and valve 2. Fig. 3 is a partial cross-sectional view of the female half of the coupling in the uncoupled condition. Fig. 3 illustrates the female valve 2 seated against the inner member 12. Referring again to Fig. 1, the male portion 19' of the coupling engages the inner body 12 of the female portion 1'. Figure 2 is a cross-sectional view of the male half 19' of the coupling. Male member 19' includes male body 19, male valve 20, seal 44, a seal retainer 63, a spring housing 48, and a spring housing support 49. Spring housing support 49 is press fitted into engagement with the spring housing 48. Spring housing 48 guides the male valve 20, seal retainer 63 and seal 44 when the male and female coupling halves are engaged. See Figs. 1 and 1A. Spring 47 operates between the spring housing 48 and the seal retainer 63. Seal 44 seals against the body 19 of the male. Valve 20 includes face 45 for engagement with a corresponding face 56 of the female valve. Snap ring 46 holds the male member 19' assembly together. Male valve body 19 includes a recess 50 for cooperative locking action with detent members 17. Referring to Figs 1 and 1 A, fluid flows past the support 49 as the supports 49 are spaced about the circumference of the spring housing 48. The inner body 12 of the female portion includes a chamber 5 formed by the relief valve positioning member 10 and the piston 3. When chamber 5 is pressurized, piston 3 is urged against inner, body member 12 and valve positioning member 10 is urged into engagement with snap ring 15. When male member 19' enters the pressurized female member 1' during coupling, shoulder 72 on the male member urges detent members 17 and inner body member 12 leftwardly. Pressure in chamber 5 keeps the relief valve positioning member against snap ring 15 and the relief valve positioning member is also urged leftwardly as the inner body member is moved leftwardly. As the relief valve positioning member is urged and moves leftwardly, one or more vent valves 7 will follow the contour 66 of the sleeve 8 resulting in the depression of valve(s) 7 and venting the female member through the second port 6 of the housing 1 of the female member 1'. Once pressure is vented in the female, the valve 2 will open under the urging of the male valve 20 and the male body 19 proceeds further into the female. As this is occurring, detents 17 move outwardly into the first interior recess 36 in the locking sleeve. As the detents 17 move outwardly, the male body 19 moves still further into the female member under the urging of an external force, for instance, the operator's hand until recess 50 in the male body 19 resides in proximity (inwardly) to the detents allowing them to subsequently move inwardly when the operator releases the external force. Spring 13 returns the inner body member 12 rightwardly. Fig. 1 A is a view similar to that in Fig.1. Two vent valves 7 are employed in the embodiment illustrated in Fig. 1A . Plug 22 is not used in Fig 1 A and instead two vent valves share a mutual spring 11 which resides between them. Both Figs. 1 and 1A illustrate vent valves 7 sealing the interior of the female member 1'. Fig. 4 is a partial cross-sectional view of the female half 1' of the coupling illustrating, among other things, a relief valve positioning member having two relief (vent) valves 7 and a two piece venting assembly 51, 52. Referring to Fig. 5, reference numeral 54 represents a threaded interconnection for securing the two piece venting assembly 51, 52. The two piece venting assembly is cylindrically shaped and includes a passageway 71 for fluid flow into the assembly. Referring to Figs. 1, 1A, 3, 4, and 5 a threaded insert or sleeve 8 is secured to the bore of the housing 1. Reference numeral 29 represents the threaded interconnection between the sleeve 8 and the housing 1. Sleeve 8 includes circumferential recess 53. It will be understood by those skilled in the art that the housing or body 1 of the female portion 1' of the coupling may assume just about any shape that may convenient for application (for example, mounting) of the invention. Further, it will be understood by those skilled in the art that the body 1 will include a stepped bore of varying diameters along its axial length. Similarly it will be understood by those skilled in the art that the inner body member 12, piston 3, and valve 2 are generally cylindrically shaped. When the relief valve positioning member 10 is positioned as illustrated in Figs. 1, 1A, 3, 4, and 5 the valve or valves 7 as the case may be, are allowed to protrude away from the axis of the coupling and to seal the interior of the coupling. Referring to Figs. 4 and 5, seals 26 prevent fluid from escaping along vent valves 7 and along the interface of the relief valve positioning member 10 and the annular sleeve 8. Reference numeral 64 refers to a bracket which performs the dual function of acting as a spring brace and as a seal retainer. A plurality of seals 65 are used to seal the two piece venting assembly 51, 52 illustrated in Figs 4 and 5. Fig 6 is a partial cross-sectional view of the male and female halves of the coupling in the coupled condition similar to Fig. 1 except the passageway 55 interconnecting the inlet port 4 to the interior of the female half of the coupling is in the valve instead of the piston. The passageway 55 is located in the female valve 2 such that it always communicates to the interior of the valve 2 despite its relative position with respect to the piston 3. In other words, the piston 3 never covers up and blocks the flow of fluid through the passageway 55. Fig. 7 is a view similar to Fig. 5 illustrating the vent valves off-center and to the right. This condition occurs when the male portion 19' is in the process of being uncoupled from the female portion 1' of the coupling. Referring to Fig. 1, for example, as the male portion 19' of the coupling is in the process of being withdrawn from the female portion of the coupling, the recess 50 in the male coupling is engaging the detents 17 in the inner body member 12 of the female portion of the coupling. As male portion 19' is pulled rightwardly, inner body member 12 of the female member also moves rightwardly. The inner body member 12 includes an annular snap ring 15 which resides in a groove 28 in the interior of the inner body member 12. Snap ring 15 engages the relief valve positioning member 10 and urges it rightwardly when viewing Fig. 1, for example. As relief valve positioning member is urged rightwardly, valve 7 (or valves 7 the embodiments employed in Figs. 1A or 4 are under consideration) follows the contour 66 of sleeve 8 causing the valve(s) to be depressed inwardly toward the axis of the coupling. As valves 7 are depressed inwardly, fluid within the coupling escapes past seals 26 and along the interface between positioning member 10 and sleeve 8. Locking sleeve 14 of the female portion compresses spring 18 which resides between a shoulder on the locking sleeve 14 and washer 16. Referring again to Fig 1, for example, as male portion 19' is pulled rightwardly by an external source (by hand, for example), spring 13 acting between the first interior shoulder 32 of female housing 1 and first exterior shoulder 31 of inner body member 12 on the one side and interior shoulder 34 of locking sleeve 14 and second exterior shoulder of inner body 12 on the other side urges locking sleeve 14 (which is in frictional engagement with the plurality of detent members 17 (balls 17) ) rightwardly until the external extraction force overcomes the friction between the detents and the locking sleeve. Additionally, locking sleeve 14 may engage washer 16 (Fig. 1) or fitting 75 (Fig. 4). Land 35 on the locking sleeve is in frictional engagement with the detent members 17 in the coupled condition and during a portion of the time during the uncoupling process. Additionally, land 35 of the locking sleeve 14 is in frictional engagement with the detent members 17 when the coupling is uncoupled (Fig. 3) and during a portion of the time when the coupling is in the process of being coupled. After, the external extraction force overcomes the friction between the detents and the locking sleeve, the detents then are free to move outwardly into the second interior recess 37 of the locking sleeve 14. Spring 13 is then compressed by the locking sleeve 14 in combination with spring 18. Those skilled in the art will recognize that snap ring 38 resides in an external groove in the inner body member 12 of the female member and serves to prohibit the movement of the locking sleeve therebeyond. A plurality of seals are used in the instant invention. Elastomeric seal 39 prohibits fluid passage between piston 3 and positioning member 10. Elastomeric seal 40 prohibits fluid passage between piston 3 and inner body member 12. Elastomeric seal 41 prohibits fluid passage piston 3 and female valve 2. Elastomeric seal 42 prohibits fluid passage between inner body 12 and female valve 2. And, elastomeric seal 43 seals between the male member 19' and the inner body member 12 of the female member 1'. Elastomeric seals 30 seal ports 4 and 24. See, Fig. 1. Fig. 8 is a view similar to Fig. 5 illustrating the vent valves off-center and to the left. This situation will occur during coupling of the male and female halves of the coupling together. Referring to Figure 3, for example, the detent members are initially under land 35. As male member 19' enters and moves the inner body member 12 leftwardly, pressurized chamber 5 maintains relief valve positioning member 10 against snap ring 15 and positioning member 10 is urged leftwardly. Valve 7 follows the contour 66 of the sleeve 8 which urges valve 7 inwardly compressing spring 11. Fluid within the female valve then escapes around seals 26. Those skilled in the art will recognize that the invention as described herein is by way of example only and will enable many variations of the disclosed invention without deporting from the spirit and scope of the appended claims.

Claims: CLAIMS: 1. A coupling comprising a male portion and a female portion; said female portion comprises: a housing, an inner body member positioned within said housing and slidable relative thereto, said housing includes a first port and a second port, said inner body member includes a port communicating with said first port of said housing, a relief valve positioning member, said relief valve positioning member includes a relief valve, a piston residing intermediate said relief valve positiomng member and said inner body member and slidable relative to said positioning member and said inner body member, said piston includes an interior, an exterior, and a passageway interconnecting said interior of said piston and said exterior of said piston, a valve, said valve slidably engaging said piston and seating against said inner body member; a chamber formed intermediate said piston and said positioning member; said male portion engaging said inner body of said female portion and moving said inner body toward said second port; said chamber being pressurized; and, said pressurization of said chamber causing said positioning member to abut said inner body member and to move with said inner body of said female portion urging said relief valve positioning member toward said second port opening said relief valve and venting said female member through said second port of said housing of said female member. 2. A coupling as claimed in claim 1. wherein said male portion of said coupling engages said valve of said female portion. 3. A coupling comprising a male portion and a female portion; said female portion comprises: a housing, a locking means, an inner body member positioned within said housing and slidable relative thereto, said housing includes a first port and a second port, said inner body member includes a port communicating with said first port of said housing, a relief valve positioning member, said relief valve positioning member includes a relief valve, said inner body member further includes a groove in the interior thereof and a snap ring residing in said groove, a piston residing intermediate said relief valve positioning member and said inner body member and slidable relative to said positioning member and said inner body member, said piston includes an interior, an exterior, and a passageway interconnecting said interior of said piston and said exterior of said piston, a valve, and, said valve slidably engaging said piston; said locking means of said female portion securing said male portion and said female portion together; said male member urging said inner body member of said female member away from said second port of said female member during uncoupling; said snap ring in said groove of said inner body member of said female member engages said relief valve positioning member during uncoupling opening said relief valve and venting said female member through said second port of said housing of said female member. 4. A coupling as claimed in claim 1 wherein said relief valve positioning member includes a venting assembly, said venting assembly comprises a first half and a second half, said first and second halves of said venting assembly are affixed together, and, at least one of said first and said second halves of said venting assembly include a vent valve. 5. A coupling as claimed in claim 3 wherein said relief valve positioning member includes a venting assembly, said venting assembly comprises a first half and a second half, said first and second halves of said venting assembly are affixed together, and, at least one of said first and said second halves of said venting assembly include a vent valve. 6. A coupling comprising a male half and a female half, said female half includes means for venting said female half when said male and female halves are being coupled and uncoupled. 7. A coupling comprising a male half and a female half, said female half includes and inner body member and a means for venting said female half of said coupling, said inner body member actuating said means for venting said female half of said coupling when said male and female halves are in the process of being coupled or uncoupled. 8. A coupling as claimed in claim 1 wherein said female member further includes a sleeve affixed to said housing, said sleeve includes a recess therein, and, said relief valve does not engage said recess when said male member urges said inner body of said female member in the direction of said second port of said housing. 9. A coupling as claimed in claim 3 wherein said female member further includes a sleeve affixed to said housing, said sleeve includes a recess therein, and, said relief valve does not engage said recess when said male member urges said inner body of said female member away from said second port of said housing. 10. A female half of a coupling having an axis comprising a housing; said housing includes a bore, an inlet port and an outlet port; said bore includes a recess therein; a first valve for communication between said inlet port and another coupling half; a relief valve in said bore of said housing for communicating between said inlet port and a reservoir; said relief valve oriented perpendicularly to the axis of said coupling and operable against said bore of said housing; said relief valve being closed when operating against said recess in said bore; and, said relief valve being open when not operating against said recess in said bore. 11. A coupling as claimed in claim 1 wherein said chamber is pressurized by fluid from said first port.

Inventors: ZEIBER DENNIS, ZEIBER, DENNIS
Applicants: SNAP TITE TECH INC, SNAP-TITE TECHNOLOGIES, INC.
Application year: 1998
Main classification: A01B
IPC codes: F16L37