Multiple-Passage, Quick-Disconnect Coupling

1. Field of the Invention

This application relates to fluid couplings and, more particularly, to fluid couplings used in multiple-passage conduits or cylinders.

2. Description of the Prior Art

In any application where hydraulic fluid is to be transported from one point to another by a conduit, it is often necessary or desirable to quickly and easily connect and disconnect portions of the conduit. Hydraulic couplings or connectors suitable for use in joining one conduit to another are well known in the art. However, these connectors generally include a protruding portion which fits into a recessed portion. Several problems arise from this particular arrangement. Since these connectors are frequently used in hostile and dirty environments, dirt and other foreign matter frequently accumulate within their recesses. When the protruding portion is fitted into the recessed portion and fluid is allowed to flow, this dirt mixes with the hydraulic fluid. Furthermore, when the protruding portion is fitted into the recessed portion, air is frequently trapped therein, causing air bubbles to form in the hydraulic fluid.

Even under circumstances where these prior art connectors would work properly for joining single-passage conduits, it was frequently difficult to devise such connectors that would simultaneously join multiple-passage conduits.

Because of these many disadvantages, there has been a great need for a hydraulic connector that could be quickly and easily connected and disconnected without allowing air or foreign matter to enter the fluid and which could be used to join conduits having multiple passages.

It is an object of the present invention to provide a coupling suitable for use in multi-passage conduits and which may be quickly connected and disconnected without the use of skilled manpower or specialized tools.

It is a further object of the present invention to provide a quick-disconnect coupling suitable for joining multipassage conduits wherein the coupling will automatically close when the conduits are depressurized.

It is still another object of the present invention to provide a multiple-passage, quick-disconnect coupling which has no dirt catching recesses.

It is a still further object of the present invention to provide a multiple-passage, quick-disconnect coupling that will not trap air within the valve structure.

It is another object to provide a multiple-passage, quick-disconnect coupling that automatically enables pressurization of the remaining passages when one passage is pressurized.

Basically, one feature of the invention is to provide a two-section coupling having a first valve operative when pressurized to move from one section to positively open a mating valve in the second section and simultaneously to open the other valves in the two sections for enabling the pressurization of the conduits connected to the other valves.

These and other objects of the present invention are accomplished in a preferred embodiment by providing a multiple-passage, quick-disconnect coupling consisting of a supply assembly and a receiver assembly. The supply assembly has a smooth, flat top surface. The supply assembly contains a plurality of valves, each valve having a top surface which is flush with the flat top surfaces of the supply assembly. The valves are opened by being raised above the flat top surface of the supply assembly. Each of the valves is actuated by a spindle connected to a piston mounted in a hydraulic cylinder. A control fluid port is provided for passing fluid to the pistons and to raise the valves above the flat top surface to open the valves. A plurality of fluid inlet ports are in communication with the inlet side of the valves.

The receiver assembly comprises a cylindrical member with a flat bottom surface. The receiver assembly contains a plurality of valves, each valve having a bottom surface which is flush with the flat surface of the receiver assembly at a location aligned with the valves in the supply assembly. The valves in the receiver assembly are opened by having their flush surfaces mechanically depressed by the supply assembly valves into the flat bottom surface of the receiver assembly.

The flat surface of the supply assembly is held against the flat surface of the receiver assembly by a clamp, with the receiver assembly aligned with the supply assembly so that the valves of each assembly confront one another. Pressurized fluid is then passed into the control fluid inlet of the supply assembly and thence to the pistons of the supply assembly valves, thereby forcing the valve members in the supply assembly into the receiver assembly to open the valves in both the supply and receiver assembly. Fluid is now free to flow into the separate fluid inlets for each valve, through the supply assembly and into the receiver assembly.

When the assemblies are depressurized, all the valves are automatically closed to prevent leakage of hydraulic fluid or ingress of dirt.

Although this multiple-passage, quick-disconnect coupling can be advantageously used to join any multi-passage conduits lying horizontally or vertically, it is particularly suited for fastening a multi-cylinder hydraulic ram to a rigid base and its hydraulic supply. It is especially suitable for use where such hydraulic rams operate in dirty environments, such as in oil well drilling rigs.

FIG. 1 is a partial cross-sectional view of the quick-disconnect coupling of the present invention as used in a multi-cylinder hydraulic ram showing the receiver assembly separated from the supply assembly.

FIG. 2 is a cross-sectional view of the receiver assembly of the present invention showing the valves in their closed position.

FIG. 3 is a cross-sectional view of the supply assembly of the present invention showing the valves in their closed position.

FIG. 4 is a partial cross-sectional view of the quick-disconnect coupling of the present invention showing the supply assembly connected to the receiver assembly and the valves in their open position.

The multiple-passage, quick-disconnect coupling is shown in FIG. 1 as used with a multi-cylinder ram. Inner ram 10 has an end 20 provided with unsealed guide bushings 20a and is urged upward when hydraulic fluid flows into the inner ram cylinder 21 through inner ram fluid port 30, Similarly, the middle ram 12 has an end 22 and is urged upward when hydraulic fluid flows into middle ram cylinder 23 through middle ram fluid port 32. The end 22 has unsealed guide bushings 22a and an axial extension 26 that overlies and is sealed against the inside surface of outer ram 14. When extension 26 is raised off the outer ram 14, fluid from the inner ram fluid port 30 is allowed to flow directly into the middle ram cylinder 23 to extend the middle ram. The outer ram 14 operates in essentially the same manner as middle ram 12. The outer ram 14 has an end 24 and unsealed guide bushings 24a and is urged upward when hydraulic fluid flows into outer ram cylinder 25 through the outer ram fluid port 34. Outer ram 14 also has an axial extension 27 which, when raised off the inside surface of the outer casing 40 by fluid introduced in port 34, enables fluid from port 30 to flow directly into the outer ram cylinder 25.

The multi-cylinder ram has three modes of operation controlled by conventional external valving. In the first mode (high speed), fluid enters only inner ram fluid port 30, thereby raising the inner ram 10. In a second mode (intermediate speed), fluid simultaneously enters both inner ram fluid port 30 and middle ram fluid port 32, thereby raising inner ram 10 and middle ram 12. Similarly, in the third mode of operation (low speed), fluid enters all three fluid ports, 30, 32 and 34, and the greatest amount of power can be achieved; but the rams 10, 12 and 14 will rise the slowest.

Although the operating parameters of each multicylinder ram will vary, depending upon the weight and dimensions of the ram, in one operational embodiment, 100 p.s.i. is needed to overcome the deadweight of the rams.

The receiver assembly 5 is shown in FIGS. 1 and 2 and includes an inner ram valve 60, a middle ram valve 70 and an outer ram valve 100, each of which is mounted flush with the flat surface 6.

The inner ram valve 60 includes a valve 59 having a flat surface 68 and a circumferential recess 58 containing an O-ring 62 which abuts a valve seat 64. The valve 59 is urged downward by a compression spring 52 which abuts a shoulder 56 on the valve member 59 and the shoulder 54. A spindle 50 extends through the compression spring 52 from the valve 59 and threadingly interacts with a nut 51. The nut 51 is adjusted so that the flat surface 68 of the valve 59 is flush with the flat surface 6. When the valve 59 is forced upward, the valve separates from the valve seat 64 to allow hydraulic fluid to flow into chamber 53 through apertures 55 and into inner ram fluid port 30.

The middle ram valve 70 is smaller than the inner ram valve 60 but operates in the same manner. The valve has a flat surface 94 and a circumferential recess 88 containing an O-ring 90 which abuts a valve seat 92. The valve is urged downward by a compression spring 78 which abuts a shoulder 82 and a shoulder 84. Extendng upward through the compression spring 78 is a spindle 72 which threadingly interacts with a nut 74. The nut 74 is adjusted to maintain the flat surface 94 of the valve flush with the flat surface 6. The operation of middle ram valve 70 is the same as the operation of the inner ram valve 60. When the valve is urged upward, the valve rises above the valve seat 92, thereby allowing hydraulic fluid to flow into chamber 81 through apertures 85 and into the middle ram fluid port 32.

The outer ram valve 100 is identical to the middle ram valve 70, both in structure and in operation, and, therefore, it will not be separately described herein.

The casing 40 is secured to a coupling body 41 by retaining bolts (not shown) which extend from the flat surface 6 through a bore in the coupling body 41 and threadingly interact with casing 40. A plurality of O-rings 42, 44 and 46 prevent hydraulic fluid from leaking at the joint between the casing 40 and the coupling body 41. A plurality of O-rings 130, 132 and 134 are provided on the flat surface 94 to prevent hydraulic fluid from leaking when the receiver assembly is connected to the supply assembly 300.

The supply assembly 300, which mates with the receiver assembly, is shown in FIGS. 1 and 3. The supply assembly 300 includes an inner supply valve 320, a middle supply valve 400 and an outer supply valve 500, all of which are flushly mounted with the flat surface 610.

The inner supply valve 320 has a flush surface 324 and a circumferential recess 326 containing an O-ring 328 abutting a valve seat 325. A cylindrical spindle 330 is connected to the valve and extends downwardly therefrom. The spindle 330 contains an axial cylindrical bore 332 in communication with a chamber 335 through apertures 334. The chamber 335 opens up into a fluid port 336 having suitable fittings (not shown) for connection to a fluid line. The axial cylindrical bore 332 extends downward through the spindle 330 and opens into cylinder 353. Hydraulic fluid flows into chamber 335 through the fluid port 336, down the axial bore 332 and into the cylinder 353, thereby forcing the piston 350 upward to raise the valve above the flat surface 610. A piston 350 is urged downward by a compression spring 344 which abuts a shoulder 348 on the piston 350 and a shoulder 346 on an inner supply valve cylinder 338. O-rings 354, 340 and 342 are provided to prevent the leakage of hydraulic fluid. The piston 350 contains a cylindrical protrusion 362 on which the lower end of the spindle 330 rests and a downwardly extending, cylindrical protrusion 356 which rests on stop 358 to maintain the piston 350 in its proper position. The cylinder 353 also opens into a fluid duct 380 through aperture 360 which, as will be explained hereinafter, allows fluid to flow into the cylinders for outer supply valve 500 and middle supply valve 400.

The middle supply valve 400 includes a flat surface 404 and a circumferential recess 406 containing O-ring 408 which abuts a valve seat 405. A spindle 410 extends downward from the valve and is fastened to piston 426 by retaining nut 428. The piston 426 is urged downward by compression spring 420 which abuts a shoulder 424 on the piston 426 and a shoulder 422 on the middle supply valve casting 414. The piston 426 includes an upwardly extending, cylindrical protrusion 432 on which the lower end of the spindle 410 rests and a downwardly extending, cylindrical protrusion 434 resting on a stop 436 to maintain the piston 426 is its proper position. The piston 426 is forced upward to open the supply valve 400 by hydraulic fluid flowing into cylinder 429 through aperture 438 from fluid duct 380. Therefore, when hydraulic fluid flows into the fluid port 336, the middle supply valve 400, as well as the inner valve 320, are opened. In one operational embodiment, a pressure of between 25 and 30 p.s.i. is needed to open the valves 400 and 320. When the middle supply valve 400 is opened, hydraulic fluid can flow through fluid port 412, through chamber 413 and past the valve 400 into the receiver assembly.

O-rings 416 and 418 are provided in middle supply valve cylinder 414 to prevent the leakage of hydraulic fluid.

The outer supply valve 500 is identical to the middle supply valve 400, both in construction and mode of operation, and, therefore, it will not be separately described herein.

A plurality of plugs 614 are provided in body 310 to prevent leakage of the hydraulic fluid from the supply valves through bores 618. One bore 618 is coupled to the fluid reservoir to vent the cylinders above pistons 326, 426 and 526. Similarly, a plurality of plugs 382 are provided in bottom plate 385 to prevent leakage of the hydraulic fluid from fluid duct 380.

A bottom plate 385 is secured to coupling body 310 by a plurality of bolts (not shown) which extend through bottom plate 385 and threadingly interact with the body 310. O-rings 620, 622 and 624 prevent the leakage of hydraulic fluid at the point where the body 310 is secured to the bottom plate 385. A locking clamp 220 is used to hold the flat surface 6 of the receiver assembly against the flat surface 610 of the supply assembly 300. The locking clamp includes clamp sections 202, 204 and 206, pivotally connected to each other by pins 210 and 212. Each of the clamp sections 202, 204 and 206 has a beveled edge 207 which mates with the beveled surface 2 on receiver assembly 5 and the beveled surface 612 on supply assembly 300. The receiver assembly is placed against the supply assembly 300, and the locking clamp 220 is fastened around the beveled surfaces 2 and 612 by fitting cylindrical members 621 and 622 through notch 609. Cylindrical member 222 is threaded to a housing 230 containing an integral pivot 228 and handle 226 pivotally mounted in the housing 230 by pin 232. The clamp 220 is locked in place by rotating the handle 226 to thread the housing tightly against the members 208.

The operation of the multiple-passage, quick-disconnect coupling of the present invention will now be explained with reference to FIG. 4 wherein the receiver assembly and the supply assembly are clamped together and valves 160, 70, 500, 320 and 400 are open.

The flat surface 6 of the receiver assembly is initially placed against the flat surface 610 of supply assembly 300 and held together by locking clamp 220. At this time, the valves will be in the position shown in FIG. 1. Pressurized hydraulic fluid then enters fluid port 336 and flows through the axial cylindrical bore 332 and spindle 330 to the cylinder 353. The fluid entering the cylinder 353 flows into fluid duct 380 through the aperture 360 and out through apertures 538 and 438 into cylinders 529 and 429. The pistons 526, 350 and 426 are then forced upward, thereby raising valves 320, 400 and 500 above flat surface 610, thereby opening the valves. The upward movement of the supply valves pushes the valves 100, 60 and 70 inwardly into the receiver assembly.

Since all of the valves are now open, the fluid entering fluid port 336 of inner supply valve 320 flows into the inner ram fluid port 30, thereby raising inner ram 10. Control fluid separately entering fluid port 412 is allowed to flow into middle ram fluid port 32 to initially raise the middle ram and the piston is then exposed to fluid in the inner ram port 30 for further extension. Fluid entering fluid port 512 raises the outer ram 14 in an identical manner.

When the rams are depressurized, the valves in the receiver assembly will automatically close, preventing the hydraulic fluid from escaping. Since all of the valve surfaces are flat, there are no recesses for dirt or air to collect in and contaminate the hydraulic fluid.

While the embodiment shown contains three passages, it is apparent that the present invention can readily be adapted to include more or less passages. Accordingly, the present invention is not limited to the precise structure illustrated.