PNEUMATIC MOTOR DISTRIBUTOR SPOOL SEAL Russian patent published in 2005 - IPC

FIELD: mechanical engineering.

SUBSTANCE: invention can be used in spool distributors with rotating spool. Proposed seal contains sealing bushing with axial channel spring-loaded relative to spool and installed radially in bore of head from side of spool coaxially to intake port. End face surface of bushing in contact with spool is made with radius of curvature equal to radius of spool, and side cylindrical surface is provided with ring seals and it includes additional sealing elements arranged in ring grooves on side surface of spool symmetrically relative to cross plane passing along axis of bushing and intake port at distance exceeding radius of bushing. Fitted in each ring groove of spool are spiral seal in form of multicoil cylindrical spiral with closed coils of wire of rectangular section and spacer made of elastic strip with rows of cross cuts with lobes bent outwards and turned to form a ring. Cross-section of ring groove is symmetrical polygon whose outer part pointed to cylindrical surface of bore is made in form of equilateral trapezium adjoining, through its larger base, inner part, which is rectangle. Spiral seal is interference fitted into outer trapezium-shaped part of ring groove. Outer side surface of extreme coils of spiral seal adjoining side surface of trapezium-shaped part of ring groove is made tilted-conical, and spacer element is installed in inner rectangular part of ring groove. Elastic outward bent lobes of spacer element press spiral seal to side cylindrical surface of bore for seal.

EFFECT: improved sealing.