GB1307094A - Sealing means between relatively movable parts - Google Patents

Abstract

1307094 Rotary shaft seals MATHER CO 13 Oct 1970 48471/70 Heading F2B A rotary shaft 10 is sealed by means comprising a P.T.F.E. sealing ring 50, Fig. 1, of J cross-section, of substantially uniform thickness, the outer portion 52 of the vertical leg of the J being secured to the shaft housing 15 and the hook portion of the J having a bottom portion 54 extending axially of and in sealing contact with the shaft over an area 11 and an end portion 56 extending substantially perpendicular to the shaft, two spaced higher load areas 12, 13 being formed at the edges of the sealing contact area 11. In the embodiment shown in Fig. 1, the portion 52 is clamped together with a gasket 30 between flanges 28, 29 in a cup 22 fitted in the housing 15 and the ring 50 is urged against the shaft by a garter spring 70. In a modification, Fig. 2 (not shown), the gasket (30) extends radially inwardly to provide a flange (32) which contacts the shaft to form a grit-excluding sealing lip. In Fig. 3, the sealing ring 250 is bonded to a plastics housing 222 and helical vanes or ridges 257 are provided on the portion 253 of the ring to return any leakage past the shaft sealing area. The load area 13 may be provided by a P.T.F.E. strip 360 as in Fig. 4 or by an edge (457), Fig. 5 (not shown), formed by a notch in the leg portion (453) of the sealing-ring (450). The sealing rings are originally of L- section and are bent to a J-section either, before installation, by forming over a mandrel which may be heated or, after installation, by heating either due to friction or from a separate heat source.