Gate valve with two sliding closure plates - has toothed rack on each plate, meshing with drive pinion between

摘要

The gate valve has a closure member consisting of two plates (4a, 4b) each having a half-round recess. In the open position of the valve the two recesses form between them a circular opening (5) for the flow. The valve is closed by sliding the plates towards each other until their unrecessed parts cover respective halves of the flow passage (2). The plates each have an extension (7a, 7b) incorporating a toothed rack. The racks of the two plates are on opposite sides of a pinion (8). When the latter is rotated the plates move in opposite senses for the opening and closing action.