Abstract: A gas turbine engine includes a fan located at a forward portion of the gas turbine engine. A compressor section and a turbine section are arranged in serial flow order. The compressor section and the turbine section together define a core airflow path. A rotary member is rotatable with at least a portion of the compressor section and with at least a portion of the turbine section. An electrical machine is coupled to the rotary member and is located at least partially inward of the core airflow path in a radial direction. An enclosure at least partially encloses the electrical machine. The enclosure at least partially defines a first cooling airflow path within the enclosure that at least partially defines a first cooling airflow buffer cavity at least partially around the electrical machine.

Abstract: A gas turbine engine includes a fan located at a forward portion of the gas turbine engine. A compressor section and a turbine section are arranged in serial flow order. The compressor section and the turbine section together define a core airflow path. A rotary member is rotatable with at least a portion of the compressor section and with at least a portion of the turbine section. An electrical machine is coupled to the rotary member and is located at least partially inward of the core airflow path in a radial direction. An enclosure at least partially encloses the electrical machine. The enclosure at least partially defines a first cooling airflow path within the enclosure that at least partially defines a first cooling airflow buffer cavity at least partially around the electrical machine.

Abstract: In one exemplary embodiment, a gas turbine engine is provided. The gas turbine engine defines a radial direction, an axial direction, and an axis extending along the axial direction of the gas. The gas turbine engine includes: a shaft configured to rotate about the axis; an electric machine comprising a rotor coupled to and rotatable with the shaft and a stator, the rotor defining an end along the axial direction; and a cooling manifold rotatable with the rotor and positioned at the end of the rotor, the cooling manifold configured to receive a flow of cooling fluid and provide the cooling fluid to the stator during operation of the gas turbine engine.

Abstract: In one exemplary embodiment, a gas turbine engine is provided. The gas turbine engine defines a radial direction, an axial direction, and an axis extending along the axial direction of the gas. The gas turbine engine includes: a shaft configured to rotate about the axis; an electric machine comprising a rotor coupled to and rotatable with the shaft and a stator, the rotor defining an end along the axial direction; and a cooling manifold rotatable with the rotor and positioned at the end of the rotor, the cooling manifold configured to receive a flow of cooling fluid and provide the cooling fluid to the stator during operation of the gas turbine engine.

Abstract: A gas turbine engine includes a fan located at a forward portion of the gas turbine engine. A compressor section and a turbine section are arranged in serial flow order. The compressor section and the turbine section together define a core airflow path. A rotary member is rotatable with at least a portion of the compressor section and with at least a portion of the turbine section. An electrical machine is coupled to the rotary member and is located at least partially inward of the core airflow path in a radial direction. An enclosure at least partially encloses the electrical machine. The enclosure at least partially defines a first cooling airflow path within the enclosure that at least partially defines a first cooling airflow buffer cavity at least partially around the electrical machine.

Abstract: A method of ejecting a drop of fluid includes providing a fluid ejector. The fluid ejector includes a substrate, a MEMS transducing member, a compliant membrane, walls, and a nozzle. The substrate includes a cavity and a fluidic feed. A first portion of the MEMS transducing member is anchored to the substrate. A second portion of the MEMS transducing member extends over at least a portion of the cavity and is free to move relative to the cavity. The compliant membrane is positioned in contact with the MEMS transducing member. A first portion of the compliant membrane covers the MEMS transducing member, A second portion of the compliant membrane being anchored to the substrate. Walls define a chamber that is fluidically connected to the fluidic feed. At least the second portion of the MEMS transducing member is enclosed within the chamber. A quantity of fluid is supplied to the chamber through the fluidic feed.

Abstract: A printer includes a printhead die including liquid ejectors separated by walls. Each liquid ejector includes a nozzle orifice and an associated drop forming mechanism. First and second liquid feed channels, extending in opposite directions, are in fluid communication with each liquid ejector. A liquid inlet includes a plurality of first and second segments in fluid communication with the first liquid feed channels and the second liquid feed channels, respectively. The first and second segments are located on opposite sides of the nozzle orifice. For a given liquid ejector, both of the first and second segments are directly in line with the liquid ejector. An electrical lead extends from each drop forming mechanism toward an edge of the printhead die. At least one of the electrical leads is positioned between neighboring segments of at least one of the first and second segments of the liquid inlet.

Abstract: A liquid ejector includes a substrate, a heating element, a dielectric material layer, and a chamber. The substrate includes a first surface. The heating element is located over the first surface of the substrate such that a cavity exists between the heating element and the first surface of the substrate. The dielectric material layer is located between the heating element and the cavity such that the cavity is laterally bounded by the dielectric material layer. The chamber, including a nozzle, is located over the heating element. The chamber is shaped to receive a liquid with the cavity being isolated from the liquid.

Abstract: A liquid ejector includes a structure defining a plurality of chambers with one of the chambers including a first and second surface. The first surface includes a nozzle orifice. A drop forming mechanism is located on the second surface of the chamber opposite the nozzle orifice. First and second liquid feed channels are in fluid communication with the chamber. First and second segments of a segmented liquid inlet are in fluid communication with the first and second liquid feed channels, respectively. The first and second segments of the segmented liquid inlet are also in fluid communication with another one of the plurality of chambers. Liquid is provided to the chamber through the first and second liquid feed channels from the segmented liquid inlet. A drop of the liquid is ejected through the nozzle orifice of the chamber by operating the drop forming mechanism.

Abstract: An inkjet printhead including a drop generator includes: a substrate including a surface; a chamber disposed on the surface of the substrate, the chamber including: an inlet having a first edge and a second edge, the second edge being separated from the first edge by an inlet width along an inlet width direction; and a chamber center, wherein the first edge and the second edge of the inlet are disposed on a same side of the chamber center relative to the inlet width direction.

Abstract: A method of ejecting a drop of fluid includes providing a fluid ejector. The fluid ejector includes a substrate, a MEMS transducing member, a compliant membrane, walls, and a nozzle. The substrate includes a cavity and a fluidic feed. A first portion of the MEMS transducing member is anchored to the substrate. A second portion of the MEMS transducing member extends over at least a portion of the cavity and is free to move relative to the cavity. The compliant membrane is positioned in contact with the MEMS transducing member. A first portion of the compliant membrane covers the MEMS transducing member, A second portion of the compliant membrane being anchored to the substrate. Walls define a chamber that is fluidically connected to the fluidic feed. At least the second portion of the MEMS transducing member is enclosed within the chamber. A quantity of fluid is supplied to the chamber through the fluidic feed.

Abstract: An inkjet printhead including a drop generator includes: a substrate including a surface; a chamber disposed on the surface of the substrate, the chamber including: an inlet having a first edge and a second edge, the second edge being separated from the first edge by an inlet width along an inlet width direction; and a chamber center, wherein the first edge and the second edge of the inlet are disposed on a same side of the chamber center relative to the inlet width direction.

Abstract: A method of printing with an inkjet printhead, the method includes providing an ink source that is fluidically connected to the printhead; filling a chamber of a drop generator of the inkjet printhead with ink; ejecting a drop of ink from the chamber of the inkjet printhead; and refilling the chamber with ink, wherein refilling the chamber comprises: providing an influx of ink into the chamber; and providing a circulating flow of ink around a periphery of the chamber.

Abstract: A printer includes a printhead die including liquid ejectors separated by walls. Each liquid ejector includes a nozzle orifice and an associated drop forming mechanism. First and second liquid feed channels, extending in opposite directions, are in fluid communication with each liquid ejector. A liquid inlet includes a plurality of first and second segments in fluid communication with the first liquid feed channels and the second liquid feed channels, respectively. The first and second segments are located on opposite sides of the nozzle orifice. For a given liquid ejector, both of the first and second segments are directly in line with the liquid ejector. An electrical lead extends from each drop forming mechanism toward an edge of the printhead die. At least one of the electrical leads is positioned between neighboring segments of at least one of the first and second segments of the liquid inlet.

Abstract: A printer includes a printhead and a source of liquid. The printhead includes a nozzle bore. The liquid is under pressure sufficient to eject a column of the liquid through the nozzle bore. The liquid has a temperature. A thermal modulator is associated with the nozzle bore. The thermal modulator is operable to transiently lower the temperature of the liquid as the liquid is ejected through the nozzle bore. An electrical pulse source is in electrical communication with the thermal modulator. The electrical pulse source is operable to provide a series of pulses to the thermal modulator that control the transient temperature lowering of the liquid. The series of pulses includes a first pulse applied at a first power level for transferring heat to the liquid, a second pulse applied at a second power level for transferring heat to the liquid, and a third pulse applied at a third power level for transferring heat to the liquid. The third power level is in between the first power level and the second power level.

Abstract: A liquid ejector is provided that includes a structure defining a plurality of chambers with one of the plurality of chambers including a first surface and a second surface. The first surface includes a nozzle orifice. A drop forming mechanism is located on the second surface of the chamber opposite the nozzle orifice. A first liquid feed channel and a second liquid feed channel are in fluid communication with the chamber. A first segment of a segmented liquid inlet is in fluid communication with the first liquid feed channel and a second segment of the segmented liquid inlet is in fluid communication with the second liquid feed channel. The first segment of the segmented liquid inlet is also in fluid communication with another one of the plurality of chambers and the second segment of the liquid inlet is also in fluid communication with another one of the plurality of chambers.

Abstract: A printer includes a printhead and a source of liquid. The printhead includes a nozzle bore. The liquid is under pressure sufficient to eject a column of the liquid through the nozzle bore. The liquid has a temperature. A thermal modulator is associated with the nozzle bore. The thermal modulator is operable to transiently lower the temperature of the liquid as the liquid is ejected through the nozzle bore. An electrical pulse source is in electrical communication with the thermal modulator. The electrical pulse source is operable to provide a series of pulses to the thermal modulator that control the transient temperature lowering of the liquid. The series of pulses includes a first pulse applied at a first power level for transferring heat to the liquid, a second pulse applied at a second power level for transferring heat to the liquid, and a third pulse applied at a third power level for transferring heat to the liquid. The third power level is in between the first power level and the second power level.

Abstract: A liquid ejector includes a structure defining a chamber. The chamber includes a first surface and a second surface. The first surface includes a nozzle orifice. A drop forming mechanism is located on the second surface of the chamber opposite the nozzle orifice. A first liquid feed channel and a second liquid feed channel are in fluid communication with the chamber. A first segment of a segmented liquid inlet is in fluid communication with the first liquid feed channel and a second segment of the segmented liquid inlet is in fluid communication with the second liquid feed channel.

Abstract: A printer includes a printhead and a source of fluid. The printhead includes a nozzle. The fluid is under pressure sufficient to eject a column of the fluid through the nozzle. The fluid has a temperature. An asymmetric thermal modulator is associated with the nozzle and includes a structure that transiently lowers the temperature of a first portion of the fluid as the fluid is ejected through the nozzle and a structure that transiently raises the temperature of a second portion of the fluid as the fluid is ejected through the nozzle.

Abstract: A printer includes a printhead and a source of liquid. The printhead includes a nozzle bore. The liquid is under pressure sufficient to eject a column of the liquid through the nozzle bore. The liquid has a temperature. A thermal modulator is associated with the nozzle bore. The thermal modulator is operable to transiently lower the temperature of the liquid as the liquid is ejected through the nozzle bore.