Abstract:
A circuit is disclosed for providing an 80 kilohertz sine wave to an ultrasonic transducer which includes an 80 kilohertz square wave generator driving a transistor having the primary of a transformer in its collector circuit. The secondary of the transformer drives a power transistor which has the transducer drive circuitry in its collector circuit. The transducer drive circuitry includes a transformer whose primary is connected in series with an inductor. The secondary of the transformer drives the transducer and has a capacitor connected thereacross. A third winding of the transformer is connected to have its output rectified to serve as a power supply for the square wave generator.
Abstract:
An improved ultrasonic nebulizer for administering a medicament aerosol to a patient. Output from an oscillator is connected through a series inductor to a transducer adjacent a reservoir which generates aerosol from the medicament. The inductor is tuned for series resonance with the bulk capacitance of the transducer. An impedance change in the transducer when liquid is removed or consumed from the reservoir reduces the power delivered to the transducer and prevents transducer damage.
Abstract:
Ultrasonic method and apparatus having improved turn-on. Low level power is furnished to an unloaded transducer to start it running at a desired frequency. High level power is then furnished the transducer for performing the ultrasonic operation while loaded. The high level power is stopped and the low level power is maintained, reduced or stopped before the load is removed.
Abstract:
Control consoles and methods for supplying a drive signal to a surgical tool are provided. The control console comprises a transformer with primary and secondary windings. The primary winding receives an input signal from a power source and induces the drive signal in the secondary winding to supply the drive signal to the surgical tool. A first current source comprising a leakage control winding is coupled to a path of the drive signal. The primary winding induces a first cancellation current in the leakage control winding to inject into the path of the drive signal to cancel leakage current. A sensor coupled to the path of the drive signal outputs a sensed signal to provide feedback related to leakage current. The sensor may connect to a second leakage current cancellation source and/or a fault detection stage. The power source may be variable and may also energize the second current source.
Abstract:
Described herein are methods and systems for testing transducers and associated integrated circuits. In some cases, a method or system described herein can comprise modulating a bias voltage using a test signal in order to produce a modulated bias voltage signal useful in testing a plurality of transducers of a transducer array in parallel.
Abstract:
A method includes applying a high frequency signal to an electromechanical actuator and measuring a first response of the electromechanical actuator to the high frequency signal, estimating electrical parameters of the electromechanical actuator based on the first response, applying a low frequency broadband signal to the electromechanical actuator and measuring a second response of the electromechanical actuator to the low frequency broadband signal, and estimating mechanical parameters of the electromechanical actuator based on the second response and the estimated electrical parameters.
Abstract:
A pulsation damper for damping pressure medium vibrations in a hydraulic system, has a membrane within a bore of a housing, which membrane is exposed to the pressure medium on its one side and faces a gas-filled cavity inside the housing on its other side, the bore of which is closed by means of a plug. The membrane, in conjunction with the plug and a hollow-cylindrical support body, forms an independently handleable, functionally pre-testable assembly, for which purpose the membrane is substantially cup-shaped, and the support body extends into it.
a printed circuit board (PCB) having a first surface and a second surface; at least one energy transmitter mounted on the first surface; at least one cooling element associated with the PCB second surface, wherein the cooling element is configured to cool the at least one energy transmitter via the PCB.
a printed circuit board (PCB) having a first surface and a second surface; at least one energy transmitter mounted on the first surface; at least one cooling element associated with the PCB second surface, wherein the cooling element is configured to cool the at least one energy transmitter via the PCB.
Abstract:
An acoustic-wave generating device includes a drive circuit and a power auxiliary circuit. The drive circuit includes a capacitor chargeable via a direct-current power supply, and a drive switch to cause power to be supplied from the capacitor to an acoustic-wave source which produces heat through energization to generate acoustic waves. The power auxiliary circuit is operable to supplies power to the drive circuit to avoid a decrease of power supplied to the acoustic-wave source in an operation of generating a series of acoustic waves from the acoustic-wave source through switching of the drive switch.