Patent ID: 9506569
Filing Date: 2016-11-29
CPC Classification: F16K

Claim Text:
1. A needle valve, comprising: a body having an internal flow path with a body seal area defined by a conical wall; a stem having a shaft with an end wall and a ball linkage; and a seat selectively movable by said stem amongst a plurality of positions, including a closed position in said conical wall defining said body seal area and an at least partially open position with respect to said body seal area, said seat, at least when in an open position, defining with said end wall a gap therebetween; wherein said seat defines a ball linkage housing with a cylindrical chamfered wall configured to receive said ball linkage to form a ball-and-socket joint, said ball linkage, when in said closed position in said conical wall, concentrating a load from said stem outward through said cylindrical chamfered wall against said conical wall, deforming said seat into said gap; wherein an axis is defined at least in part by said stem, and wherein said ball-and-socket joint permits rotation of said ball linkage about said axis with respect to said ball linkage housing, such that, after said stem has substantially tightened said seat in the closed position, a slippage between said ball linkage and said ball linkage housing permits said stem to turn said ball linkage about said axis, deforming said seat into said gap; and wherein said ball-and-socket joint inhibits rotation of said seat about another axis different than said axis.