GB861729A - Improvements in or relating to pipe couplings - Google Patents

Abstract

861,729. Valves. FLIGHT REFUELLING Ltd. Sept. 24, 1959 [Oct. 9, 1958], No. 32285/58. Class 135. [Also in Group XXVIII] In a pipe coupling comprising coupling parts A, B provided with main valves 11 for closing the passages through the parts, the valves are slidably mounted in non-fluid-tight housings 2 defining the inner walls of annular passages 3 through the parts and co-operate with seatings 4 at the mating ends of the parts. Pilot valves 15, 33 are provided in the valves 11 to place the housings in communication when the parts are coupled and there is valve-actuating means provided in association with the part A to open both main valves, that actuating means having a lost-motion connection with the main valves and which is utilized to open the pilot valves. Slidably mounted within the housings 2 are hollow, cup-shaped valves 11 urged by springs 12a on to the seatings 4. A tube 13, loaded by a spring 19, coaxial with and slidably mounted within the part A carries a pilot valve head 15 which co-operates with a seating 16 formed by the internal shoulder of a bush 17 screwed into the valve 11. A rod 14 slidably mounted in the tube extends through the orifice 18 towards the valve 11 of the part B and is formed a longitudinal rack 23; the tube has a similar rack and the racks are engaged by pinions 25, 26 in mesh with one another, the pinion 25 being carried by a spindle 27 having mounted thereon an operating handle 29 for rotating the spindle and simultaneously rotating the pinions to transmit opposite longitudinal motion to the tube 13 and rod 14. The pilot valve head 15 acts through the seating 16 to urge the valve 11 to closed position when the tube 14 is moved in one direction, and movement of the tube in the opposite direction, after a certain lost motion is taken up, brings the head 15 into engagement with a stop ring 30 on the bush 17 after which continued movement of the tube withdraws the valve 11 from its seating to open the passage 3 through the part A. The valve 11 in the part B carries a valve body 32 in which is located a spring-loaded ball 33 for closing an orifice 31 in the valve, and movement of the rod 14 effected simultaneously with movement of the tube 13 causes the ball 33 to be engaged, thereby to move the ball from its seating and through a limited distance so as to unseat the valve 11. When the hand wheel 34 is rotated to couple the parts A, B, a plate 38 on the handle moves out of the way of the handle 29 to permit radial movement of the handle from a position C in which the valves are closed to a position D in which the valves are in readiness for opening. Rotation of the handle to a position E causes the valves to open and after radial movement to a position F, the handle is held locked in that position by a gate 49 pivotally mounted on a bracket 50 and held in the handle engaging position by the energization of an electromagnet 52. To prevent rotation of the hand wheel in a direction to cause uncoupling of the parts A, B when the valves 11 are open, the plate 38 has a cut-out 45 in which the end of the spindle 27 locates when the spindle is rotated to open the valves. The circuit of the electromagnet is arranged to be broken under conditions when it is desirable the valves 11 shall close automatically under the action of the springs 12a, the handle 29 being released to move to the position D and from that position to position C by a torsion spring; the gate 49 is spring- loaded and reset after release of the handle. The part A is provided with a bleed valve 54 connected to the space 57 between the coupling parts and closed when the valves 11 are open and opened when the handle 29 is in its stowed position C such opening being effected by depression of the bleed valve plunger 58 by a pad 59 on the handle. The pad is also used when the handle is in the " valves open " position to operate a micro-switch controlling the electric circuit of an indicator for showing the position of the valves, the circuit being completed only when the parts A, B have been coupled.