| 摘要 |
<p>A diffuser control (26) for controlling vapor flow through a diffuser passage (16) comprising an annular recess (28) defined by a housing (12) of the diffuser passage (16) and in communication therewith, and an annular control ring (30) supported for movement within the recess (28) and the diffuser passage (16) between a throttling position, wherein the control ring (30) throttles vapor flow through the diffuser passage (16), and an open position for permitting a substantially free flow of vapor through the diffuser passage (16). The diffuser control (26) further comprises a plurality of springs (32) supported by the housing (12) for urging the control ring (30) toward the throttling position, a stop (34) for limiting movement of the control ring (30) at the throttling position, a low pressure conduit (38) for connecting the annular recess (28) to a low pressure source, and a steal (42, 44) for retarding vapor flow from a higher pressure side of the control ring (30) to a lower pressure side thereof when the control ring (30) is in the open position. A valve (40) is provided for regulating vapor flow through the low pressure conduit (38) and includes a first position for maintaining a low pressure in the annular recess (28) and a pressure difference across the control ring (30) for maintaining the control ring (30) in the open posiiton, and a second position for maintaining a high pressure in the annular recess (28) wherein the springs (32) maintain the control ring (30) in the throttling position.</p> |
