Patent GB-1085054-A (GB)
Title: Bayonet-type pipe coupling
Inventor: PADDINGTON ARTHUR LOFTUS
IPC: F16L37/248
Filed: 1963-05-17
Abstract: 1,085,054. Pipe joints; pipe closures. DRACONE DEVELOPMENTS Ltd. May 14, 1964 [May 17, 1963], No. 19742/63. Headings F2G and F2P. A bayonet-type pipe coupling, comprising two members adapted initially to make a bayonet slot and spigot engagement, is characterized by the spigots which are cam-shaped and rotatable about their axes such that they may be made to bear against their respective slot side edges to effect a further tightening of the coupling subsequent to initial engagement without further relative rotation of the coupling members. In the embodiment shown in Figs. 1 and 2 illustrating the initial and final engaged positions respectively, a male coupling member 7, comprising a ring 9, and end-flanged pipe fitting 6 and an annular synthetic rubber seal 10, carries a shaft 11 having cam-shaped spigots 18 keyed thereto at either end and mounting a butterfly valve 12, closed in the initial engaged position. Said spigots are entered into rebated bayonet slots 17 of the female member 3, an annular lip 13 abutting a further synthetic rubber seal 15 on initial engagement. A U- shaped lever 20, connected at either end by a lost-motion mechanism to the spigots as illustrated in Fig. 3 (not shown), is moved from the initial engaged position of Fig. 1 to the final or locked position of Fig. 2 thereby simultaneously opening the valve and rotating both the spigots on the shaft in unison which abut the right-hand sides of the bayonet slots to interlock the coupling members and draw the seal 10 against an annular face 16 of the member 3. In a further embodiment not incorporating a valve, Fig. 5, a plurality of equally-spaced cam-shaped spigots 32, carried by rotary spindles 46 in sealed bushes 47 in a metal ring 45 having a threaded adapter 49 for a conventional flanged pipe fitting, are individually rotated after initial engagement within the slots of the female member by a tool adapted to engage U-shaped recesses in their ends thereby compressing a single synthetic rubber seal 48 more tightly against the shallow V-shaped female member sealing face 58. The bayonet slotted ring 33 is secured to an L-section ring 36 to form a freely rotatable member abutting a self-lubricating bearing 39 screwed to a pipe adapter 38, hand wheels 40, Fig. 4 (not shown), and 57 permitting rotation of the slotted female ring 33 to effect initial engagement of the spigots within the slots without relative rotation of the respective pipes. A further embodiment, Figs. 6 and 7 (not shown), is similar to that illustrated by Figs. 1 and 2 but differs in that firstly holes are provided in the ends of the common-shaft-mounted cam-shaped spigots for rotation thereof by a tommy bar or the like inserted therethrough, and secondly, a single annular seal is incorporated which is drawn up more tightly against a " Tufnol " (Registered Trade Mark) ring carried by the female member on rotation of the spigots. The shaft ends of both the embodiments, Figs. 1, 2 and Figs. 6, 7, are mounted in bushes sealed at either face by 0-rings. The female coupling member may be closed when uncoupled by a plate having camshaped spigots operable individually or in unison to engage and lock within said member in a manner analogous to that described above. In addition, two pipes having male member end fittings may be coupled by a member formed by two internal female members in backto-back relationship.