A tail-rotor vibration dampener system for an aircraft is provided. The system includes a fuselage and an open rotor assembly including a powerplant and a set of rotor blades. The system further includes at least one actuator unit connecting the open rotor assembly to the fuselage. The actuator unit includes a hydraulic actuator controlling a position of the open rotor assembly in relation to the fuselage and a dampening device operable to cancel a vibration emanating from the open rotor assembly. The system further includes a computerized vibration dampening controller, including programming to determine a frequency of the vibration emanating from the open rotor assembly and control the dampening device to cancel the vibration emanating from the open rotor assembly based upon the frequency.

An oscillating fluidic pressure pulse generator, includes: an outer tube, an upper connector, a lower connector and a vortex fluidic oscillator. A first central fluid channel and a second central fluid channel are respectively formed in the upper connector and the lower connector, two ends of the outer tube are respectively connected to the upper connector and the lower connector through a screw thread, and the vortex fluidic oscillator is provided in the outer tube and abuts against the upper connector and the lower connector; and the vortex fluidic oscillator is provided with an inlet and connected to a fluidic oscillating chamber, two flow guiding blocks are arranged below the fluidic oscillating chamber, a vortex chamber inlet is formed between the two flow guiding blocks, two control channels are respectively formed outside the two flow guiding blocks, a vortex chamber is provided below the vortex chamber inlet.

An arrangement that can be turned by an assigned hydraulic pressure and flow, related to a chain saw supported by a harvesting unit for crosscutting timber, wherein a bearing arrangement is arranged for the chain saw and oriented between a guide bar housing and the chain saw's drive motor unit, wherewith an oscillatory motion can be activated by a hydraulic control valve, through which hydraulic flow is alternatively controlled via feed or connection lines to the bearing arrangement, for a first or second operating mode. The arrangement is activated via hydrostatic pressure and coordinated with the guide bar housing, and with the drive motor unit, via surrounding perforated discs oriented in parallel and aligned around an axis of rotation for a drive shaft. The hydrostatic affects the arrangement's oscillatory motion for a reciprocal motion pattern, while spent hydraulic oil serves as a lubricating film between the opposing bearing surfaces.

An arrangement that can be turned by an assigned hydraulic pressure and flow, related to a chain saw supported by a harvesting unit for crosscutting timber, wherein a bearing arrangement is arranged for the chain saw and oriented between a guide bar housing and the chain saw's drive motor unit, wherewith an oscillatory motion can be activated by a hydraulic control valve, through which hydraulic flow is alternatively controlled via feed or connection lines to the bearing arrangement, for a first or second operating mode. The arrangement is activated via hydrostatic pressure and coordinated with the guide bar housing, and with the drive motor unit, via surrounding perforated discs oriented in parallel and aligned around an axis of rotation for a drive shaft. The hydrostatic affects the arrangement's oscillatory motion for a reciprocal motion pattern, while spent hydraulic oil serves as a lubricating film between the opposing bearing surfaces.

An intermittent air discharge apparatus has a main valve and a pilot valve, the main valve being switched between a discharge state and a discharge stop state. The pilot valve is switched between an air-supply state to supply air to a pilot chamber for air-discharge, and an air-supply stop state. When the pilot valve is switched to the air-supply state, an exhaust passage communicates with the pilot chamber for air-discharge. When the pilot valve is switched to the air-supply state, a supply or exhaust passage allows an air supply passage to communicate with the pilot chamber for air-discharge and a pilot chamber for stopping air-supply; when the pilot valve is switched to the air-supply stop state, communication with the air supply passage is blocked. A flow rate of air from the pilot chamber for air-discharge is set by the exhaust passage, and a flow rate of air from the pilot chamber for stopping air-supply is set by the supply or exhaust passage.

A method is provided for actively compensating for pressure changes of a working fluid within a conduit. A first cavity is provided in fluid communication with the conduit. A second cavity is in fluid communication with a control fluid. A plunger is in communication with both the first cavity and the second cavity and is movable in response to pressure changes of the working fluid in the conduit. The plunger is re-centered. Re-centering the plunger includes the following steps. Position data representative of movement of the plunger is collected. The position data is analyzed with a control unit to determine an average position of the plunger which is offset relative to a center position. The average position of the plunger is compared, with a control unit, to the center position. A signal is relayed from the control unit to a control valve to urge the plunger toward the center position.

A method is provided for actively compensating for pressure changes of a working fluid within a conduit. A first cavity is provided in fluid communication with the conduit. A second cavity is in fluid communication with a control fluid. A plunger is in communication with both the first cavity and the second cavity and is movable in response to pressure changes of the working fluid in the conduit. The plunger is re-centered. Re-centering the plunger includes the following steps. Position data representative of movement of the plunger is collected. The position data is analyzed with a control unit to determine an average position of the plunger which is offset relative to a center position. The average position of the plunger is compared, with a control unit, to the center position. A signal is relayed from the control unit to a control valve to urge the plunger toward the center position.

A conformal, cup-shaped fluidic nozzle engineered to generate an oscillating spray is configured as a (e.g., 100, 400, 600 or 700). Preferably, the fluidic circuit's oscillation inducing geometry 710 is molded directly into the cup's interior wall surfaces and the one-piece fluidic cup may then fitted into an actuator (e.g., 340). The fluidic cup (e.g., 100, 400, 600 or 700) conforms to the actuator stem used in typical aerosol sprayers and trigger sprayers and so replaces the prior art “swirl cup” 70 that goes over the actuator stem (e.g., 320), With the fluidic cup (e.g., 100, 400, 600 or 700) and method of the present invention, vendors of liquid products and fluids sold in commercial aerosol sprayers 20 and trigger sprayers 800 can now provide very specifically tailored or customized sprays.

A conformal, cup-shaped fluidic nozzle engineered to generate an oscillating spray is configured as a (e.g., 100, 400, 600 or 700). Preferably, the fluidic circuit's oscillation inducing geometry 710 is molded directly into the cup's interior wall surfaces and the one-piece fluidic cup may then fitted into an actuator (e.g., 340). The fluidic cup (e.g., 100, 400, 600 or 700) conforms to the actuator stem used in typical aerosol sprayers and trigger sprayers and so replaces the prior art “swirl cup” 70 that goes over the actuator stem (e.g., 320), With the fluidic cup (e.g., 100, 400, 600 or 700) and method of the present invention, vendors of liquid products and fluids sold in commercial aerosol sprayers 20 and trigger sprayers 800 can now provide very specifically tailored or customized sprays.

A fluidic component having a flow chamber allowing a fluid flow to flow through, said fluid flow entering the flow chamber through an inlet opening of the flow chamber and emerging from the flow chamber through an outlet opening of the flow chamber, and which flow chamber has at least one means for changing the direction of the fluid flow at the outlet opening in a controlled manner. The flow chamber has a main flow channel, which interconnects the inlet opening and the outlet opening, and at least one auxiliary flow channel as a means for changing the direction of the fluid flow at the outlet opening in a controlled manner. The inlet opening has a larger cross-sectional area than the outlet opening or the inlet opening and the outlet opening have cross-sectional areas that are equal in size.