Packing seal construction

TL;DR: In this article, a packing for relatively-movable parts comprises a housing member 24, Fig. 3, having an annular recess 27, an O-ring 37 compressed between a wall of the recess 27 and the inner bearing surface 35 of the member 31, the packing being fixed to either of the two relatively movable parts and the sealing surface 34 having sliding contact with the other.

Abstract: 876,985. Stuffing-box substitutes; piston packings. TAYLOR-EMMETT CONTROLS Inc. Dec. 12, 1957, No. 38649/57. Classes 122 (1) and 122 (5). A packing for relatively-movable parts comprises a housing member 24, Fig. 3, having an annular recess 27, an annular sealing member 31 of tough, low-friction plastic material, such as polytetrafluoroethylene, located in the recess and having cylindrical bearing and sealing surfaces on its opposite sides, and an O-ring 37 compressed between a wall of the recess 27 and the inner bearing surface 35 of the member 31, the packing being fixed to either of the two relatively-movable parts and the sealing surface 34 of the member 31 having sliding contact with the other. The housing member 24 is mounted either as a fixed member in a gland structure or on the movable member. As shown in Fig. 3, the housing member is sealed in the gland space 20 by a sealing ring 26 and the sealing member 31 is of L-shape; the O- ring 37 is of circular or D cross-section. If desired, the housing 24 may be provided with two annular recesses each fitted with a sealing member 31 and O-ring 37. A piston constructed of two recessed discs 77, 79, Fig. 8, clamped on a rod 80 on opposite sides of a central disc 78, has a T-shaped housing member 84 located in each recess 82 and carrying on each side of its leg an L-shaped sealing member 86 and O-ring 88.