Abstract:
Various arrangements for determining an atomization element of a nebulizer is dry are presented. The vibratable element of the nebulizer may be energized with an electrical signal that sweeps from a first frequency to a second frequency. While energizing the vibratable element of the nebulizer with the electrical signal that sweeps from the first frequency to the second frequency, a sequence of impedance values of the vibratable element of the nebulizer may be measured. The sequence of impedance values of the vibratable element of the nebulizer may be analyzed to determine if the atomization element of the nebulizer is wet or dry.
Abstract:
In the ultrasonic aerosol apparatus (10) the temperature of the piezoelectric ceramic element is controlled by an N.T.C. thermistor (40). The piezoelectric ceramic element (38) is of the vitrified type. The joints between the component parts of the apparatus casing (12) do not involve either the water container if the apparatus is of indirect atomization type, or the container for the liquid medicament to be atomized. The piezoelectric ceramic element (38) is supported by elastic means (16), which can be of electrically conductive material to also act as the electrical connection between the piezoelectric ceramic element and the N.T.C. thermistor (40).
Abstract:
In an ultrasonic frequency generating assembly including a frequency generator coupled to a transducer through an output stage, a current measuring circuit is coupled to the output stage for sampling the current therethrough during each frequency burst upon the passage of a predetermined time interval following the onset of the respective frequency burst. The current value measured during a frequency burst is compared with a measured current value from an immediately preceding burst, the frequency output of the frequency generator being modified in accordance with the results of the comparison. The compared current values are stored in respective memories, the most recently measured current value being transferred from one memory to the other upon the termination of the comparison. A new current value is then loaded into the first memory.
Abstract:
Ein Ultraschallschwinger (1) wird durch das Ausgangssignal eines spannungsgesteuerten Oszillators (4) angeregt. Dieser wird mit einem Dreieckgenerator (5) so geregelt (6, 7), dass seine Frequenz in einem die Serienresonanz des Ultraschallschwingers umschliessenden Bereich periodisch gewobbelt wird. Man bildet eine der Dämpfung des Ultraschallschwingers entsprechende Messgrösse (I, V) und vergleicht sie mit einer höchstzulässigen Dämpfung. Ist die festgestellte Dämpfung kleiner ist als die höchstzulässige Dämpfung, wird der Oszillator (4) zusätzlich in Abhängigkeit von der Messgrösse geregelt. Diese ist vorzugsweise eine Funktion des Anregungsstroms (I) des Ultraschallschwingers. Vorzugsweise wird davon ein momentaner Wert (24) und ein verzögerter Wert (8) gebildet und deren Differenz mit einem Schwellenwert verglichen (9): wenn diese Differenz gleich dem Schwellenwert wird, wird die Wobbelrichtung (7, 5) umgekehrt. Die Leistung am Ultraschallschwinger kann durch Variation der Betriebspannung (U) der dem Ultraschallschwinger vorgeschalteten Endstufe (2) geregelt werden. Das Verfahren ist zur Zerstäubung einer Flüssigkeit durch einen mit einem Zerstäuberteller versehenen Ultraschall schwinger verwendbar.
Abstract:
Zum Betrieb eines Ultraschallflüssigkeitszerstäubers (3), vorzugsweise mit einer Piezokeramik (4), die gegebenenfalls einen temperaturabhängigen Widerstand (10) aufweist, wird für den automatischen Frequenzabgleich eine Strommessung während der Zeitdauer des Burstimpulses t₁ nach einer Verzögerungszeit t₃ für die Zeitspanne t₄ vorgenommen. Die Summe aus der Verzögerungszeit t₃ und der Zeitspanne t₄ darf nicht größer als die Burstzeit t₁ sein.
Abstract:
In various arrangements, a nebulizer element of a nebulizer may be energized with a drive signal. A phase offset of the drive signal may be measured. A phase delta may be determined. The phase delta may indicate a difference between a target phase offset and the measured phase offset. The target phase offset may indicate a non-zero target phase difference between the voltage of the drive signal and the current of the drive signal. A frequency of the drive signal may be changed to decrease the phase delta.
Abstract:
Various arrangements for determining an atomization element of a nebulizer is dry are presented. The vibratable element of the nebulizer may be energized with an electrical signal that sweeps from a first frequency to a second frequency. While energizing the vibratable element of the nebulizer with the electrical signal that sweeps from the first frequency to the second frequency, a sequence of impedance values of the vibratable element of the nebulizer may be measured. The sequence of impedance values of the vibratable element of the nebulizer may be analyzed to determine if the atomization element of the nebulizer is wet or dry.
Abstract:
In the ultrasonic aerosol apparatus the temperature of the piezoelectric ceramic element is controlled by an N.T.C. thermistor. The piezoelectric ceramic element is of the vitrified type. The joints between the component parts of the apparatus casing do not involve either the water container if the apparatus is of indirect atomization type, or the container for the liquid medicament to be atomized. The piezoelectric ceramic element is supported by elastic means, which can be of electrically conductive material to also act as the electrical connection between the piezoelectric ceramic element and the N.T.C. thermistor.