ROTARY SEAL ARRANGEMENTS

摘要

1,248,780. Shaft seals. DANFOSS A.S. 4 Dec., 1968 [16 Jan., 1968], No. 57601/68. Heading F2B. A seal for a rotary oil pump shaft 1 comprises a seal ring 16 urged by spring means 12 into facial sealing contact with a seating plate 4 and sealed to the shaft 1 or shaft housing 2 by a resilient sealing ring 18 and a resilient backing ring 19 compressed by spring means 12 between a tapered surface 22 on the ring 16 and a cylindrical surface 21 on the shaft or shaft housing. In the embodiment shown in Fig. 1 in which the ring 16 rotates with the shaft 1, and the spring 12 is compressed between a ring secured to the shaft and a plate 13 having extensions 14 engaging recesses 15 in the ring 16. The ring 18 is compressed between the plate 13 and the backing ring 19 which has a tapered outer surface 23 of a slope greater than that of the surface 22. The plate 4 is sealed to the housing 2 by an O-ring 7. The rings 18 and 19 may be of synthetic rubber and plastics material, e.g. P.T.F.E., respectively. In a modification, Fig. 2 (not shown), the seating plate (41) is secured to the shaft (11) and the seal ring (161) is keyed to the shaft housing (21) so that it is non-rotatable but axially movable and the sealing ring (181) and backing ring (191) are compressed by the spring (121) between the tapered surface (221) on the ring (161) and a counterbore (29) in the housing (21).