Patent ID: 6802488
Filing Date: 2004-10-12
Classification: F16K

Abstract:
A coaxial valve for controlling a flow of a liquid or gaseous flow medium therethrough, including: a valve body, a valve housing with an inlet, an outlet and a flow channel passing in a longitudinal direction therethrough from the inlet to the outlet; a closing body provided with a valve seat arranged in the housing flow channel; a ball screw actuator including a ball nut and a cylindrical screw, with the ball nut surrounding a threaded portion of the screw; the cylindrical screw having a passageway therethrough forming a cylinder through which fluid flows, the cylindrical screw being disposed in the flow channel to become a control tube allowing the flow medium co flow therethrough, the control tube being adapted to move in the longitudinal direction toward and away from the valve seat of the closing body when rotated by the ball nut, one end of the control tube being adapted to abut the valve seat of the closing body when so moved; and an actuating drive adapted to rotate the ball nut to advance the control tube to a closed position in which the control tube end contacts and seals against the valve seat of the closing body to close the flow channel, and to advance the control tube to an open position in which the control tube end is spaced a distance apart from the closing body to provide an opening between the control tube end and the closing body to allow the flow medium to flow through the control tube and through the valve housing outlet.