GB911403A - Self-sealing couplings for fluid lines - Google Patents

Abstract

911,403. Pipe couplings. DUFFIELD, F. R. May 29, 1961, No. 19247/61. Class 99(1). In a self-sealing coupling for high-pressure hydraulic or pneumatic pipe lines and which comprises first and second coupling members adapted to screw one into the other and to open valves in each member against the action of springs respectively tending to hold the valve members on to the seats thereof, the first member includes a coupling part 12 and a fixed valve member 17, constituting a valve seat, surrounded by an annular sliding part 19, constituting a valve member upon which one of the springs 21 acts, the member 17 and part 19 having normally-aligned, truncated, conical faces which engage upon the displaceable valve member 38 and a coupling part 39 respectively of the second coupling member during coupling to force the displaceable valve member and the part 19 from the seats thereof. As shown, the coupling part 12 is provided with a tubular valve member 17 having a head portion 18 and fluid ports 29, and an annular part 19 incorporating a sealing ring 25 slidable on the member is urged by a spring 21 on to an annular shoulder 24 of the portion 18; a bleed hole 27 is provided in the member 17. The cooperating coupling part comprises three tubular members 30, 33 and 40, the member 40 having an inner frustoconical surface 39, on which seats the sealing ring 44 of a spring-loaded valve 38, and a screwthreaded portion 42 which is engageable with a screw-threaded part 14 of the part 12. Relative rotation between the members 30 and 40 is prevented by a grub-screw 48, and the member 30 has a vent hole 59. In coupling the parts, the forward end of the member 40 abuts the member 19 to displace the latter and uncover the ports 29, and the valve 38 is displaced axially by the member 17; fluid pressure also assists in opening the valve 38. A shoulder 47 coincides with the end of the member 30 to indicate when the members 12 and 30 are fully screwed together. A handwheel 60 on the member 30 facilitates tightening of the coupling member; alternatively, the member carries a protective shroud which may be rotatably mounted on the member. In modifications, (a) the valve in the part 12 includes a stem 50 fixed in a web 51 having fluid ports 58, and (b) the valve in the cooperating coupling part is a spring-loaded poppet valve and a leather washer is located in front of the 0-ring 26 in the ridge 23 of the part 19.