Patent GB-811739-A (GB)
Title: Flexible hose line assembly
IPC: F16L33/22
Filed: 1956-06-29
Abstract: 811,739. Hose couplings. AEROQUIP CORPORATION. June 29, 1956 [Oct. 11, 1955], No. 20295/56. Class 99(1). A hose line assembly comprises in combination a metallic end fitting 18 having a socket 20, a nipple 24 and an intermediate sleeve 26 embracing the nipple, and a flexible hose 12 having an inner tube 14 and an outer reinforcement 16, the latter being expanded by the outer surface of the sleeve and gripped between the sleeve and the socket. The inner tube is of deformable material, e.g. of polymerized tetrafluoroethylene, incapable of sustaining forces of compression of fluid sealing magnitude in use and has a lip seal portion 28 defined by the terminal end of the tube and disposed between the nipple and sleeve, the latter parts having opposed coaxial cylindrical surface portions for deforming the portion 28 into contiguous relationship with a surface portion of the sleeve. At least one inwardly projecting annular rib 42 of generally saw-toothed form is provided on the cylindrical surface portion of the sleeve, the leading side of the tooth sloping to facilitate insertion of the tube within the sleeve, and the rib being spaced from either end of the sleeve or from any other such rib by a distance at least equal to the wall thickness of the tube and the height of the rib being a fractional part of that wall thickness. The nipple and sleeve are so shaped and dimensioned with respect to the undeformed wall thickness of the tube portion 28 as to restrict initial compression forces to that required to effect deformation into contiguous relationship about the rib with the sleeve as dinstinguished from initial compression forces of fluid sealing magnitude, the portion 28 as deformed being readily actuated by fluid pressure radially outward from the surface of the nipple into fluid sealing engagement with the sleeve. As shown in Fig. 2, the socket 20 has an internal conical surface 48 and is screwed on to the nipple 24 which is provided with a conical surface 36 forming a metal-to-metal, fluidsealing contact with a rounded, annular shoulder 34 of the sleeve 26, the latter having a knurled conical outer surface 46 of a taper greater than that of the surface 48. In assembly, the nipple 24 is inserted into the hose 12 to loosen the wire braid 16 from the tube 14 and then withdrawn, after which the sleeve 26 is positioned between the braid and the tube and the nipple is reinserted into the tube; the socket is then screwed on to the nipple to bring the shoulder 34 and surface 36 into contact and wedge the braid between the surfaces 46, 48. The diameter of the nipple may be equal to or greater than that of the bore of the tube 14, and the shoulder 34 may be complementary to the surface 36 to distribute the loading of the sealing therebetween over a greater area. In modifications (a) the nipple has an external, annular rib similar to those provided on the sleeve, (b) the compression fitting 50, Fig. 6, has a socket portion 52, a nipple portion 54, and an intermediate sleeve 56 provided with annular ribs, and (c) the nipple has an angularly-adjustable elbow extension. Specification 733,337 is referred to.