| 摘要 |
A valve device for regulating the flow of a fluid though a flexible pipeline comprises a piston means 5 arranged axially displaceable in a cylinder means 23, 25 and secured against rotation, one end of said piston means being arranged to press the flexible pipeline 31 against a backstop 33 and the other end of said piston being provided with an axial, threaded bore 13 for receiving an adjustment screw 7, which is coupled to the axle of a reversible electric motor 11, preferably via a gearbox 9, for being rotated therewith, whereby activating of the motor 11 with entailed rotation of the adjustment screw 7 causes lengthwise displacement of the piston means in the cylinder means 23, 25 in one or the other direction, depending on the direction of rotation. The backstop 33 is adjustably arranged relative to the cylinder means 23, such that the clamping action on the flexible pipeline 31 between the backstop 33 and the piston means 5 is adjustable for a given position of the piston means in the cylinder means. Preferably, the device comprises electrical end stops 55, 57 arranged to be activated by the piston means 5 for cutting off the current supply to the electric motor 11, both when the piston means reaches a first limit position displaced towards the flexible hose pipeline 31, and when the piston means reaches a second limit position displaced away from the flexible hose pipeline, whereby damage on the pipeline and the mechanical parts of the device as a result of excess displacement of the piston means is prevented. <IMAGE> |
