Abstract: An aircraft can include a stacked propeller to generate lift during assent and descent. The stacked propeller includes a first propeller and a second propeller that co-rotate about an axis of rotation. In one embodiment, the blades are coupled to a rotor mast that contains an internal cavity. In one mode of operation, the first propeller and/or the second propeller can be stored in the internal cavity in order to reduce drag during flight. The aircraft can include one or more stacked propellers, such as a port propeller and a starboard propeller, which rotate in opposite directions during one or more modes of flight.

Abstract: To provide a traveling control mechanism and a traveling control method capable of controlling a traveling mechanism taking into consideration operation contents of a remote control valve. The problem is solved by a traveling control mechanism comprising a remote control valve (21, 22, 23, 24), a pressure adjusting solenoid valve (61, 62), a setting mechanism (70), and a controller (60). The traveling mechanism (8) allows a traveling speed to be switched between a high speed and a low speed in accordance with an operation amount of the remote control valve (21, 22, 23, 24). An HST circuit (30) is provided with a pump (31, 32) and a traveling motor (33), the pump (31, 32) connects to a pilot line (41, 42, 43, 44) allowing a hydraulic oil supplied from the remote control valve (21, 22, 23, 24) to flow therethrough, a pressure sensor (45) is attached to the pilot line (41, 42, 43, 44), and a rotation sensor (65) is attached to the traveling motor (33).

Abstract: A prime mover and a plurality of hydraulic actuators, a hydraulic machine having a rotatable shaft in driven engagement with the prime mover and comprising working chambers, a hydraulic circuit between working chambers of the hydraulic machine and the hydraulic actuators, each working chamber of the hydraulic machine comprising a low-pressure and high-pressure valves regulating the flow of hydraulic fluid between the working chamber and a corresponding low-pressure manifold and a high-pressure manifold. The hydraulic machine being configured to actively control the low-pressure valves of the working chambers to select the net displacement of hydraulic fluid by each working chamber on each cycle of working chamber volume, and thereby the net displacement of hydraulic fluid by the working chambers, responsive to a demand signal, wherein the apparatus further comprises a controller configured to calculate the demand signal in response to a measured property of the hydraulic circuit or actuators.

Abstract: Vibration damping devices and methods utilizing the same for damping vibrations in a fan. A vibration damping device for a fan, the fan having an inlet side of a frame and an exhaust side of the frame and the frame retains a fan mechanism. The vibration damping device includes a mass mT which may include either: a block with a total mass mT; or a finger guard and at least one resilient attachment member having a first spring characteristic, wherein resilient attachment member is configured to be connected to and retain the mass mT. The vibration damping device may be tunable to damp the vibration of fan by (a) varying the total mass mT of the block, or replacing the finger guard, and/or (b) replacing the at least one resilient attachment member with a second resilient attachment member having a second spring characteristic.

Abstract: Articles of manufacture, preferably pump component parts, and a method for making the articles, include providing a plurality of layers of reinforcing fibers in a stack of consecutive layers in a matrix of synthetic polymeric material. The reinforcing fibers of different layers are of corresponding different materials, and the layers are arranged such that the material of the reinforcing fibers in each layer is different from the material of the reinforcing fibers in the next consecutive layer. The layers are stitched together with further reinforcing fibers extending within the stack essentially perpendicular to the layers and interspersed throughout the stack. The stack is compressed and cured to establish a block having a plurality of layers of reinforcing fibers and further reinforcing fibers in a matrix of synthetic polymeric material. The block is machined to establish a prescribed configuration of a desired article.

Abstract: A hydraulic control system for control of a hydraulic motor. The hydraulic control system comprises a fluid distribution assembly having a tank, a pump to pump fluid from the tank and a directional valve for distributing pressurised fluid from the pump and to return fluid to the tank; a valve assembly fluidly connected to the directional valve, the valve assembly having a first overcenter valve and a pressure reducing valve wherein a first main line connects the directional valve to the first overcenter valve and wherein a shuttle line connects the pressure reducing valve to the first main line; a hydraulic motor fluidly connected to the valve assembly wherein the first main line connects the hydraulic motor to the first overcenter valve; and a brake assembly fluidly connected to the pressure reducing valve, wherein a drain line connects the pressure reducing valve to the hydraulic motor.

Abstract: A linear actuator system includes a linear actuator and at least one proportional control valve and at least one pump connected to the linear actuator to provide fluid to operate the linear actuator. The at least one pump includes at least one fluid driver having a prime mover and a fluid displacement assembly to be driven by the prime mover such that fluid is transferred from the pump inlet to the pump outlet. The linear actuator system also includes a controller that establishes at least one of a speed and a torque of the at least one prime mover and concurrently establishes an opening of the at least one proportional control valve to adjust at least one of a flow and a pressure in the linear actuator system to an operational set point.

Abstract: A fan blade with improved structure includes a hub, a plurality of blades. The hub has a lateral side having two ends, one of which is formed a top side and the other end is extended to form an extended section, and a plurality of connecting slots located on the periphery of the extended section. Each blade has a first end correspondingly engaged in respective connecting slot and a second end. With these arrangements, the fan blade with improved structure can increase structural strength of thin fan blades and be easy to connect the hub to the blades.

Abstract: A pump for pumping a liquid, includes an impeller and an axially extending drive shaft assembly, wherein a distal end of the drive shaft assembly is received in a central recess of the impeller. The drive shaft assembly includes a drive shaft and a connector. The connector includes a sleeve that is in telescopic engagement with the drive shaft. During operation of the pump the impeller is displaceable in the axial direction in relation to the sleeve between a distal rest position and a proximal position. The impeller is biased towards the distal rest position by a spring member arranged between the sleeve and the impeller. The connector includes a hollow adjustment screw that is in threaded engagement with an interior side of the sleeve to limit the maximum degree of telescopic overlap between the sleeve and the drive shaft.

Abstract: An apparatus comprises a gas turbine engine having a compressor for increasing a total pressure of a working fluid prior to delivery to a combustor for mixing with fuel. The compressor has a plurality of airfoil members that extend between a first flow surface and a second flow surface. The plurality of airfoil members have a first camber shape at a tip portion that provides a cumulative integral according to the relationship 0.4 < ? 0 1 ? [ ? 0 x ? ? ? ? dx ] ? dx ? 0 1 ? ? ? ? dx ? 0.5 where x is chord location, ? ? = ? i - ? ? i - ? e , ?i is inlet metal angle, ?e is exit metal angle, and ? is a camber angle at a given chord location.

Abstract: A fan assembly in which all of the major structural components of the assembly are mechanically fastened together by non-welding means, such as mechanical fasteners, is disclosed. The disclosure also relates to a fan assembly in which the major structural components have planar segments separated by bend lines that approximate a curved shape, and that can be formed, for example, by a press brake machine. Such a construction can eliminate the necessity for rolling, welding, and painting of the structural components of the fan assembly.

Abstract: The present disclosure relates to devices, systems, and methods for controlling and/or augmenting acoustic sounds emitted from flight vehicles, such as unmanned aerial vehicles (UAVs). For example, while in flight, a UAV may emit a characteristic sound or tone (or a plurality of such tones), which may be a result of propeller and/or motor noise. To mitigate such noise from UAVs, disclosed embodiments may include acoustic resonators that may provide additional tones to complement the sounds or tones emitted from the UAV. Namely, the acoustic resonators may be shaped, adjusted, or otherwise controlled to emit additional tones that form pleasing intervals in combination with the characteristic tone(s) from the UAV.

Abstract: A pressing tool is described for plastically deforming a workpiece. The pressing tool comprises a piston pump driven by a motor that rotates in operating rotation direction RA and a pressure release valve and a coupling arrangement, which mechanically couples the motor to the pressure relief valve, so that the motor opens the pressure relief valve when operated in a loosening rotation direction RL opposite to the operating rotation direction RA. Also described is a corresponding method of operating a pressing tool.

Abstract: An impeller back surface cooling structure for cooling a back surface of a compressor impeller of a supercharger includes: a first member facing a back surface of a compressor impeller via a gap; and a second member extending in a circumferential direction of the compressor impeller and forming, between the first member and the second member, a cooling passage through which a cooling medium being a liquid flows.

Abstract: A turbine engine turbine including a nozzle stage made of ceramic matrix composite material and including a plurality of annular sectors forming an annulus presenting an inner shroud and an outer shroud, each sector having an inner platform forming a portion of the inner shroud, an outer platform forming a portion of the outer shroud, and at least one airfoil extending between the outer and inner platforms and secured thereto. A metal ring includes at least one annular sector, and presents an outer surface in contact with the surface of the inner shroud opposite from the surface from which the airfoils extend, the metal ring presenting an outside diameter at its outer surface that is greater than the diameter of the inner shroud such that the nozzle stage is held in compression between a casing and the metal ring.

Abstract: A compressor moves a fluid from an inlet to an outlet and provides a pressure differential there between due to respective pistons moving in and out of a plurality of piston chambers via a piston rod. A rotating shaft extends through a grooved end plate, and the rotating shaft is connected to either the grooved end plate or the piston rod. The grooved end plate defines an off center or eccentric groove. A bearing extends from the piston rod and fits within the groove such that when the rotational motion of the shaft rotates either the piston rod or the grooved end plate, the piston rod slides back and forth relative to the rotating shaft. Each position of the bearing within the groove determines a corresponding position of the piston rod relative to the rotating shaft. Each pair of pistons may extend from a single, continuous piston rod.

Abstract: A diffuser for a radial compressor of a turbomachine is provided. The diffuser has a plurality of diffuser channels, wherein the diffuser channels extend across a radial area of the diffuser across a bent area into an axial area of the diffuser, wherein, in the radial area of the diffuser, the diffuser channels have diffuser walls in particular at v-shaped blades that are bent in the movement direction of the radial compressor or are straight.

Abstract: A turbine system including a sealing component is presented. The sealing component is positioned in a gap between adjacent turbine components of the turbine system. The sealing component includes a metallic shim including a high-temperature-resistant alloy in a single crystal form. A turbine shroud assembly including the sealing component is also presented.

Abstract: A rotor blade for a wind turbine is provided. The rotor blade includes a pressure side, a suction side, a leading edge section with a leading edge, and a trailing edge section with a trailing edge. An airflow flows along the surface of the rotor blade from the leading edge section to the trailing edge section and builds up a boundary layer in close proximity to the surface of the rotor blade. The rotor blade includes a noise reduction device for reducing noise which is generated by interaction of the airflow and the rotor blade. The noise reduction device is located within the boundary layer of the rotor blade. The noise reduction device includes a cover and connection device for connecting the cover to the surface of the rotor blade. The cover spans at least over a part of the surface of the rotor blade.

Abstract: A control arrangement for a coolant pump of an internal combustion engine includes a control slide which controls a throughflow cross-section of an annular gap arranged between an outlet of a coolant pump impeller and a surrounding delivery duct. A control pump adapts a hydraulic pressure generated in a flow duct. An electromagnetic valve includes a first and second valve seat, a first, second and third flow connection, a closing member and an armature. The first flow connection is fluidically connected to an outlet of the control pump. The second flow connection is fluidically connected to a first pressure chamber of the control slide. The third flow connection is fluidically connected to an inlet of the coolant pump. The first valve seat is arranged between the first flow connection and the second flow connection. The second valve seat is arranged between the second flow connection and the third flow connection.