| 摘要 |
The invention relates to a mechanical device for the cut-off of fluid, particularly suitable for corrosive and polluting fluids, comprising an annular sealing member of packing displaceable towards and against the seal seating by means of a series of screw pins acting on the sealing member through a series of springs; each screw pin is only displaceable along its axis but not rotatable and has the thread thereof engaged with a threaded part of a corresponding pinion, all the pinions being rotatable by means of only one gear, whereby the rotation of said gear causes the screw pins and thus the sealing member to be displaced towards and against the sealing seat, the displacement in the opposite direction being only possible upon said gear is rotated in the opposite direction. |
