A duct assembly may include a first duct, a second duct, and a flexible joint assembly coupling the first duct to the second duct. The flexible joint assembly may include a bellows having a first end and a second end and a plurality of convolutions located therebetween, and a gimbaled joint assembly. The gimbaled joint assembly may include a first support surrounding the first end of the bellows and a first portion of the plurality of convolutions, a second support surrounding the second end of the bellows and a second portion of the plurality of convolutions, and a gimbal ring assembly operably coupled to the first support and the second support. The gimbal ring assembly may include a ring body and a plurality of flexure hinges interconnected with the ring body.

An automatic fluid pump includes a pump body having a liquid channel and a mounting channel, the liquid channel having an inlet and an outlet and connected to a suction pipe and a delivery hose, respectively. A motor fan is disposed at a lower end of the suction pipe. A power controller is coupled to the pump body and circuit-connected to a battery, a terminal plate, and a switch. A valve case is coupled to the mounting channel in the form of a hopper formed at a lower end thereof with an inclined portion having an air hole. A valve case cap is coupled to the valve case. A main check valve is disposed on a lower surface of the valve case cap to open/close the through-holes. An auxiliary check valve is vertically moved up and down between the mounting channel and the air hole to open/close the air hole.

A heat recovery unit with a unit housing (11) defining a unit compartment, a heat exchanger (20), a fresh air bypass flow passage and/or an exhaust air bypass flow passage, a fresh air centrifugal fan arrangement (41) and an exhaust air centrifugal fan arrangement (42), a fresh air filter (51) and an exhaust air filter (52).

A vehicle driving apparatus including: a fluid pump; a rotary member; a bearing supporting the rotary member; a pump cover covering the fluid pump; a relief valve; and a casing storing the fluid pump, the rotary member, the bearing, the pump cover and the relief valve. The casing includes a casing body and a casing cover. The casing cover defines a fluid passage that is in communication with an outlet port of the fluid pump, and includes cylindrical-shaped first and second boss portions. The first boss portion includes a supporting portion supporting the rotary member through the bearing which is fitted in a space radially inside the first boss portion. The second boss portion defines a valve room that is in communication with the fluid passage, with the relief valve being stored in the valve room.

A reverse flow gas turbine engine has a low pressure (LP) spool and a high pressure (HP) spool arranged sequentially in an axial direction. The LP spool comprises an LP compressor disposed forward of an LP turbine and drivingly connected thereto via an LP compressor gear train. The HP spool comprises an HP compressor in flow communication with the LP compressor, and an HP turbine disposed forward of the HP compressor and drivingly connected thereto via an HP shaft.

An example centrifugal compressor includes a housing that defines an inlet chamber and includes first and second openings that define a recirculation passage in fluid communication with the inlet chamber. An impeller is disposed within the housing and is rotatable about a longitudinal axis to draw fluid into the inlet chamber. The first and second openings are at different axial locations along the longitudinal axis. A plurality of inlet guide vanes are rotatable and situated in the inlet chamber. The centrifugal compressor includes a ring and a controller for moving the ring along the longitudinal axis between a first position and a second position when rotating the inlet guide vanes. The ring obstructs at least one of the first and second openings more in the second position than in the first position.

A centrifugal compressor includes a low-speed shaft, an impeller, a speed increaser, a housing, a separation wall, a shaft insertion hole, a seal member, an oil pan, an oil supply passage, an oil return passage, and a pressure reduction passage. The impeller is integrally rotated with a high-speed shaft. The housing has therein an impeller chamber accommodating the impeller and a speed increaser chamber accommodating the speed increaser. The centrifugal compressor includes a bypass passage having a first end communicating with the speed increaser chamber and a second end communicating with the oil pan.

A duct assembly may include a first duct, a second duct, and a flexible joint assembly coupling the first duct to the second duct. The flexible joint assembly may include a bellows having a first end and a second end and a plurality of convolutions located therebetween, and a gimbaled joint assembly. The gimbaled joint assembly may include a first support surrounding the first end of the bellows and a first portion of the plurality of convolutions, a second support surrounding the second end of the bellows and a second portion of the plurality of convolutions, and a gimbal ring assembly operably coupled to the first support and the second support. The gimbal ring assembly may include a ring body and a plurality of flexure hinges interconnected with the ring body.

An example centrifugal compressor includes a housing that defines an inlet chamber and includes first and second openings that define a recirculation passage in fluid communication with the inlet chamber. An impeller is disposed within the housing and is rotatable about a longitudinal axis to draw fluid into the inlet chamber. The first and second openings are at different axial locations along the longitudinal axis. A plurality of inlet guide vanes are rotatable and situated in the inlet chamber. The centrifugal compressor includes a ring and a controller for moving the ring along the longitudinal axis between a first position and a second position when rotating the inlet guide vanes. The ring obstructs at least one of the first and second openings more in the second position than in the first position.

An example centrifugal compressor includes a housing that defines an inlet chamber and includes first and second openings that define a recirculation passage in fluid communication with the inlet chamber. An impeller is disposed within the housing and is rotatable about a longitudinal axis to draw fluid into the inlet chamber. The first and second openings are at different axial locations along the longitudinal axis. A plurality of inlet guide vanes are rotatable and situated in the inlet chamber. The centrifugal compressor includes a ring and a controller for moving the ring along the longitudinal axis between a first position and a second position when rotating the inlet guide vanes. The ring obstructs at least one of the first and second openings more in the second position than in the first position.