Patent GB-973825-A (GB)
Title: Improvements in or relating to fluid-tight couplings
Inventor: VIRNOT ALAIN
IPC: F16L37/23
Filed: 1961-07-28
Abstract: 973,825. Tube couplings. ELECTRICITE DE FRANCE. July 28, 1961 [July 29, 1960; July 13, 1961], No. 27432/61. Heading F2G. A fluid-tight releasable coupling comprises coaxial tubular members 13, 19 and an annular intermediate member 24 making axial sliding fluid-tight engagement with the member 19 and having a bearing surface 27 which axially abuts and makes fluid-tight engagement with a cooperating bearing surface 17 on the member 13, a plurality of retaining elements 21 being provided movable through passages 31 in the member 24 and engaged at substantially diametrically opposite locations by oppositely facing shoulders 23, 18 on the members 13, 19 located so that upon relative movement of the members axially in one sense the elements 21 will lock those shoulders from further such relative movement while on relative axial movement of the members in the opposite sense will offer a passage for the elements 21 from between those shoulders to permit uncoupling. As shown in Fig. 2, the tube 13 is formed with tubular parts 15, 16 providing an annular space 14a, the tube 15 having a spherical bearing face 17 and the tube 16 being provided with a spherical or conical shoulder 18 machined concentrically with the face 17. The tube 19 has a number of cavities 20 and an end portion 22, including a shoulder 23 and an abutment surface 22a, and carries an intermediate piece 24 comprising coaxial tubes 25, 26, the tube 25 having a bearing face 27 fitted with fluid packings 28a, 28b; packings 29 are located between the tubes 19, 25. The tube 26 is formed by tubes 26a, 26b secured together by elastic connections 35, Fig. 5, comprising a pin 35 screwed into the tube 26b and rubber collars 40, 41 which are compressed when the tubes 26a, 26b are, respectively, displaced in the directions indicated by the arrows F1, F2. The tubes 25, 26 are linked together by pins 30, and the tube 26 includes cavities 31 in each of which is disposed a ball 21. To uncouple the tubes 13, 19, the surface 22a is brought into contact with the face 17 and so that the shoulder 23 releases the balls 21, the piece 24 then being moved axially to disengage the balls 21 from the shoulder 18 and force the balls into the cavities 20, 31 whereby the piece 24 and tube 19 are withdrawn from the tube 13. A spring 32 presses the fluid packings 28a, 28b on to the face 17. In a modification, there is a tubular element 45, Fig 6, comprising two parts 45a, 45b linked by an elastic connection 35 and which replaces the intermediate piece 24. In a further modification, the tubes 52, 51, Figs. 7 and 8, respectively incorporate valves 56, 57 having stems 56 2 , 57 2  slidable in bores 60, 61 in supporting pieces 62 1 , 63 and urged by springs 64, 65, on to seats 58, 59; the bores are connected by conduits 66, 67 to a pressure fluid. One of the valves has a bore 68 in which is a slidable piston 69. When the tubes 51, 52 are uncoupled and the valves are closed, conduits 78, 79 opening between fluid valve packings 73, 74 are subject to a fluid circuit under depression or in excess of that prevailing in the tubes so that fluid leakage from the tubes and to atmosphere is prevented. When the tubes are coupled by displacement of the intermediate piece 53 and engagement of the balls 55 in the annular groove 85 of the tube 51, the pressures on either side of the valves 56, 57 are balanced by putting conduits 80, 83 respectively into communication with conduits 81, 83. The valves are opened by placing conduits 66, 67 in communication with a fluid pressure under depression, and a pressure fluid admitted to the bore 68 via a conduit 70 moves the piston 69 to lock the valves in the open positions thereof.