摘要:
An active retractable seal assembly for use between rotating and non-rotating turbo machinery components including: a plurality of seal rings mounted to the non-rotating component, the seal rings movable toward and away from the rotating component between respective closed and open positions as a function of pressure drop across the seal rings, wherein the seal rings are normally in the open position; and a fluid bypass circuit for directing fluid around one or more of the plurality of seal rings to reduce the pressure drop across the one or more of the seal rings, thereby causing the one or more seal rings to move towards the open position under the action of spring(s) or actuator(s).
摘要:
A shaft seal assembly between a rotating shaft and a static shell is disclosed. The shaft seal assembly includes a seal housing in mechanical contact with the static shell, at least two rigid members of the seal housing, and a plurality of compliant plate members defining a sealing ring between the static shell and the rotating shaft. The plurality of compliant plate members is disposed between the at least two rigid members and retained within the seal housing by a compressive force between the at least two rigid members.
摘要:
A shaft seal serves to reduce leakage between a rotating shaft and a static shell. The shaft seal includes a plurality of compliant plate members, each having a root and a tip. The compliant plate members are secured to the static shell at their root in facing relation. The tips of the compliant plate members define a sealing ring between the static shell and the rotating shaft. An axial flow resistance member is disposed within the compliant plate members and serves as a barrier to axial leakage flow between the compliant plate members.
摘要:
A minimal access tool includes a frame arranged to be attached to an arm of a user, a tool shaft having a proximal end and a distal end, where the tool shaft proximal end is connected to the frame. The tool further includes an input joint having a first end connected to the frame and a second end arranged to receive user input, the input joint including a virtual center-of-rotation (VC) mechanism which provides a center of rotation that generally coincides with a wrist joint of the user. An output joint is connected to the tool shaft distal end, where the output joint is coupled to the input joint via a mechanical transmission connected therebetween to correlate motion of the input joint to motion of the output joint.
摘要:
An active retractable seal assembly is configured for use between a rotating component and a stationary component of turbo machinery is disclosed. The seal assembly includes a seal mounted to the stationary component. The seal is movable towards and away from the rotating component between a respective closed position and an open position as a function of pressure drop across the seal. The seal includes an active seal segment, a non-active seal segment, and a fluid by-pass circuit. The fluid by-pass circuit is configured for directing fluid around the active seal segment to reduce pressure drop across the active seal segment thereby resulting in the active seal segment moving towards an open position under the action of one or more biasing devices while maintaining the non-active seal segment in a closed position.
摘要:
An actuation pressure control system effects actuation of adjustable seal segments between stationary and rotating turbomachinery members. At least one actuator is coupled with each of the adjustable seal segments and controls a position of the seal segments, respectively. A pressure system is disposed within the turbomachinery that measures or estimates ambient pressure representing an actuator back pressure acting against the actuator. A pressure regulator via a controller pressurizes the actuator to a level sufficient for a desired seal operation and controls actuator pressure based on the actuator back pressure.
摘要:
A shaft seal serves to reduce leakage between a rotating shaft and a static shell. The shaft seal includes a plurality of compliant plate members, each having a root and a tip. The compliant plate members are secured to the static shell at their root in facing relation. The tips of the compliant plate members define a sealing ring between the static shell and the rotating shaft. An axial flow resistance member is disposed within the compliant plate members and serves as a barrier to axial leakage flow between the compliant plate members.
摘要:
A gas supply and pressure control system delivers controlled pressurized gas according to an electrical command. The system includes a gas supply sub-system outputting a continuous high-pressure gas supply. A pressure control sub-system is provided in fluid communication with the gas supply sub-system and receives the continuous high-pressure gas supply. The pressure control sub-system provides a modulated pressure to a downstream volume, such as actuators for active seals in a turbomachinery environment, based on the electrical command.
摘要:
A motion apparatus having two or five degrees of freedom includes a plurality of arm flexures, a plurality of parallelogram flexures or a plurality of compound parallelogram flexures. The motion apparatus minimizes direct, parasitic, and coupled error motions.
摘要:
An active retractable seal assembly for use between rotating and non-rotating turbo machinery components including: a plurality of seal rings mounted to the non-rotating component, the seal rings movable toward and away from the rotating component between respective closed and open positions as a function of pressure drop across the seal rings, wherein the seal rings are normally in the open position; and a fluid bypass circuit for directing fluid around one or more of the plurality of seal rings to reduce the pressure drop across the one or more of the seal rings, thereby causing the one or more seal rings to move towards the open position under the action of spring(s) or actuator(s).