Valve control mechanism for bag filters - for producing a swift, linear response when varying conditions of flow

摘要

The mechanism features a lined aperture, a flap valve moveable through a controlled distance between the open and closed positions of the aperture, a motor device to move the valve and a control arrangement for the motor. This controller is contained within the motor and is itself actuated by two control circuits. The circuit comprise delicate switching mechanisms connected in series to electrical circuits in parallel to each other and to the flap valve. When the flap valve moves through a predetermined distance it actuates a circuit to move the valve to its second position. The speed of the switching operation is controlled by a times connected to the valve. The valve controls surging of fluid under pressure and is, therefore, partic. useful in systems employing filter bags. It prevents surging when the fluid circulation is stopped or retarded when the operating conditions are changed. It produces a more controlled and swifter flow than standard ball or butterfly valves and is simpler than the device described in U.S. 3898999. Its simple, strong mechanism makes it inexpensive and easy to operate and maintain.