Abstract:
Phacoemulsification apparatus includes a phacoemulsification handpiece having a needle and an electrical system for ultrasonically vibrating said needle along with a power source for providing pulsed electrical power to the handpiece electrical system. Irrigation fluid is provided to the handpiece needle and aspirating fluid is removed from the handpiece needle. A determination of a voltage current phase relationship of the provided electrical power is made and in response thereto a control system varies a power level duty cycle provided to the handpiece electrical system from the power source and/or modify the aspiration flow rate. In addition, a separate input enables manual control of pulse amplitude. The control system provides a pulsed electrical power of less than 20 millisecond pulse duration.
Abstract:
Phacoemulsification apparatus includes a phacoemulsification handpiece having a needle and an electrical system for ultrasonically vibrating the needle along with a power source for providing pulsed electrical power to the handpiece electrical system. Irrigation fluid is provided to the handpiece needle and aspirating fluid is removed from the handpiece needle. A determination of a voltage current phase relationship of the provided electrical power is made and in response thereto a control system varies a power level duty cycle provided to the handpiece electrical system from the power source and/or modify the aspiration flow rate. In addition, a separate input enables manual control of pulse amplitude and the control system in response to a selected amplitude determines a duty cycle of the provided pulsed electrical power.
Abstract:
A control system for a probe, including a transmission member, comprises a power source for supplying a constant power to a transmission member and a transducer for coupling the constant power to the transmission member and for providing a mechanical output to the transmission member at a frequency. A frequency measuring device is also provided for constantly measuring the frequency of the mechanical output of the transducer. A current monitoring device for measuring current forwarded to the transducer which monitors the current while the frequency of said mechanical output is varied until it is determined at what frequency the current is at a maximum is also provided. A method for implementing this apparatus is also provided.
Abstract:
Phacoemulsification apparatus includes a phacoemulsification handpiece having a needle and an electrical system for ultrasonically vibrating said needle along with a power source for providing pulsed electrical power to the handpiece electrical system. Irrigation fluid is provided to the handpiece needle and aspirating fluid is removed from the handpiece needle. A determination of a voltage current phase relationship of the provided electrical power is made and in response thereto a control system varies a power level duty cycle provided to the handpiece electrical system from the power source and/or modify the aspiration flow rate. In addition, a separate input enables manual control of pulse amplitude. The control system provides a pulsed electrical power of less than 20 millisecond pulse duration.
Abstract:
Method and apparatus for modulating the vibrations of an object with a constant amplitude has a sensor, e.g., a piezoelectric transducer, for sensing the vibrations. A light source, e.g., an LED, receives the sensed signal and illuminates a light dependent resistor (LRD). In turn, a control circuit controls the vibration amplitude in accordance with the LDR resistance. A full wave bridge rectifier can be used between the sensor and the LED.
Abstract:
A circuit including a transformer, preferably a laminated piezoelectric transducer, in combination with a positive feedback amplifier circuit, capable of serving: 1) to produce either an audible or ultrasonic signal; or 2) as an energy source capable of driving an auxiliary high voltage device with an initial and continuing low voltage source such as a battery.
Abstract:
An apparatus for tuning and controlling an ultrasonic handpiece having a programmable broad spectrum source, a torsional single frequency source and a longitudinal single frequency source that generate a drive signal for an ultrasonic handpiece and a digital signal processor for analyzing a response signal generated by the handpiece in response to the drive signal and generating an adjusting signal for adjusting the torsional single frequency source and the longitudinal single frequency source.
Abstract:
The invention concerns a device enabling the gas bubbles present in a liquid composition to be dissolved. The device comprises a chamber (10) provided with an inlet orifice (11) through which the composition to be debubbled is introduced, and an outlet orifice (12) through which the debubbled composition is discharged, an ultrasonic transducer (13, 14, 15, 16, 17, 18, 19, 20), a power supply (21) for supplying the said transducer, the said power supply (21) being regulated in frequency and power at the same time.
Abstract:
A predetermined frequency and adjustable level excitation circuit for a capacitive load (B) having a first terminal connected to a reference voltage (G). The circuit includes two switches (S1, S2) connected in series between a supply voltage (Vcc) and the reference voltage (G). The junction (S) of the two switches is coupled to the second terminal (A) of the load. The two switches are not simultaneously closed. A circuit (10) periodically controls the closing of the switch connected to the supply voltage. A regulation circuit (R2, R3, 12) acts on the control circuit to trigger opening of one of the switches when the voltage across the load reaches a predetermined value.