Abstract: A method for controlling a magnetostrictive ultrasonic transducer of the type used in a magnetostrictive ultrasonic dental scaler includes generating a drive signal for a resonant circuit using a full bridge synchronous class D amplifier. The electrical signal output by the resonant circuit drives an excitation coil that generates an electromagnetic field that causes the magnetostrictive ultrasonic transducer to vibrate. A feedback wire is rendered unnecessary by measuring current and voltage outputs of the resonant circuit and quadrature sampling the measured current and voltage outputs at the same sampling rate as used for the generation of the electrical signal by the resonant circuit. A pulse width modulated signal is generated from the quadrature sampled sensed current and voltage that represents a pulse train approximation of a sine wave of the drive signal for, in turn, being applied to the full bridge synchronous class D amplifier to generate the drive signal for the resonant circuit.

Abstract: A method for controlling a magnetostrictive ultrasonic transducer of the type used in a magnetostrictive ultrasonic dental scaler includes generating a drive signal for a resonant circuit using a full bridge synchronous class D amplifier. The electrical signal output by the resonant circuit drives an excitation coil that generates an electromagnetic field that causes the magnetostrictive ultrasonic transducer to vibrate. A feedback wire is rendered unnecessary by measuring current and voltage outputs of the resonant circuit and quadrature sampling the measured current and voltage outputs at the same sampling rate as used for the generation of the electrical signal by the resonant circuit. A pulse width modulated signal is generated from the quadrature sampled sensed current and voltage that represents a pulse train approximation of a sine wave of the drive signal for, in turn, being applied to the full bridge synchronous class D amplifier to generate the drive signal for the resonant circuit.

Abstract: The invention provides an ultrasonic dental scaler insert having a soft grip, and a method of making it. In the method a soft grip member is provided having an elastomeric wall affixed to a rigid wall. This soft grip member is then connected to an ultrasonic dental scaler insert to form an ultrasonic dental scaler insert having a soft grip.

Abstract: A system and method for operating a motor drive unit. The motor drive unit is coupled to a motor driving a load and is configured to selectively control the motor according to a torque control mode and a speed control mode. The motor drive unit includes a circuit configured to generate an operational condition signal indicating an operational condition of the motor and a regulator configured to receive the operational condition signal and generate a motor control signal. The motor drive unit also includes a first controller configured to receive the motor control signal and a reference control signal and select either the motor control signal or the reference control signal to use as a control signal to drive the motor according to either torque control or speed control.

Abstract: A system and method for operating a motor drive unit. The motor drive unit is coupled to a motor driving a load and is configured to selectively control the motor according to a torque control mode and a speed control mode. The motor drive unit includes a circuit configured to generate an operational condition signal indicating an operational condition of the motor and a regulator configured to receive the operational condition signal and generate a motor control signal. The motor drive unit also includes a first controller configured to receive the motor control signal and a reference control signal and select either the motor control signal or the reference control signal to use as a control signal to drive the motor according to either torque control or speed control.

Abstract: A system and method for splicing reeled media using operational feedback. According to certain embodiments, the method of operating a media production system involves sensing speed parameters of first and second reeled media, tracking an unwinding parameter of the first reeled media, and positionally tracking a leading end position of the second reeled media. The method also involves controlling splicing between the first and second reeled media based at least partially on the speed parameters, the unwinding parameter, and the leading end position.

Abstract: The invention provides an ultrasonic scaler, comprising: a scaler tip, actuator material, a coil, a hand-piece housing, and an air driven electrical current generator. The actuator material, the coil and the air driven electrical current generator are enclosed by the hand-piece housing. The scaler tip is connected to the actuator material. Preferably the actuator material is [Tb0.30Dy0.70Fe1.92]. The invention provides an ultrasonic scaler including a scaler tip, actuator material, a coil, a hand-piece housing, and a frequency control circuit. The actuator material, the coil and the frequency control circuit are enclosed by the hand-piece housing. The scaler tip is connected to the actuator material.

Abstract: A method of lighting a scaling tip including providing a light source electrically connected to a secondary coil, and providing a scaling tip having an arm extending into a primary coil and adapted to be ultrasonically vibrated by the primary coil.