CHANGE VALVE UNIT Russian patent published in 2002 - IPC

FIELD: sanitary fittings for water supply systems. SUBSTANCE: change valve unit has body located in seat of fitting and made of set of movable and immovable flat washers. Each washer has hole; washers are supported by flexible gasket. Swivel of drive is sealed up by sealing rings. Holes of movable and immovable washers have form of figure smoothly changing its section at peripheral arc with radius R₀ from center of washer between point lying on ray and point of intersection with diameter of washer at distance (π-ϕ₀). Above-mentioned ray runs from center of washer at angle ϕ₀. relative to diameter. This angle ranges from 0 to π. Radius R₀ of peripheral arc ranges from 0.2 to 0.8 of radius of washer. Convex arc is made at radius R₁ from center laying on diameter of washer at distance equal to R₀/2 from center of washer, from point of intersection of peripheral arc with diameter of washer to intersection with diameter of washer. Length of radius R₁ ranges from 0 to R₀/2, concave arc has radius R₂ from center lying on diameter of washer as mirror image to center of convex arc relative to center of washer from point of intersection of convex arc with diameter of washer to intersection with ray. Length of radius R₂ ranges from R₀/2 to R₀. Concave and peripheral arcs are conjugated by arc of inscribed circle. EFFECT: enhanced adjusting capacity of unit due to smooth change of free area of hole of shut-off member. 9 dwg