Mechanical override for a valve actuator,申请号US20060364840-传众专利搜索

Mechanical override for a valve actuator

申请公布号：US7293575(B2)

申请号：US20060364840

申请日期：2006.02.28

申请公布日期：2007.11.13

分类号：F16K17/38;F16K31/126;F16K31/145

主分类号：F16K17/38

摘要：An apparatus and method for manual operation of an actuator is disclosed. A mechanical override includes a housing coupled to the actuator, a drive ring, and a shaft extending through a bore of the housing. The drive ring rotationally keys to the bore such that the drive ring is capable of axial movement within the bore in response to automatic operation of the actuator. A backstop limits axial movement of the drive ring during manual operation. A thread located on an external portion of the shaft threads to the drive ring. In the manual operation, the shaft rotates through the drive ring imparting axial movement to the shaft capable of moving a valve between a first position and a second position. The override provides visual indication of the valve position during both automatic and manual operation. The backstop may be an insert that selectively permits movement of the shaft to a failsafe position in response to a temperature or pressure change.