Abstract:
A method and apparatus for determining the resonance frequency for a vibration welder (12) are described. The vibration frequencies at a predetermined vibration level and on both sides of the resonance frequency are derived and are then used to determine and operate the vibration welder (12) at the resonance frequency. In one embodiment the vibration frequency of the vibration welder (12) is swept up from one side of the resonance point and the vibration amplitude is monitored and a first frequency at a particular vibration amplitude is determined. The same sweeping is done from the other side of the resonance point and a first frequency at a particular vibration amplitude is determined. The same sweeping is done from the other side of the resonance point and a second frequency determined for the same vibration amplitude reference level but on the other side of the resonance frequency. The two measured frequencies are then combined to yield the resonance frequency which can then be used to operate the vibration welder (12).
Abstract:
In the described device for stimulating an electro-acoustic ultrasound transformer having a variable load in an operating mode whereby, at a reverse strictive signal, stimulating pulses are sent in the corrected frequency and with a length not exceeding half of a period of the mechanical vibrations generated by the transformer, stimulating pulses are sent in the resonance frequency of said transformer or in a divisor of said frequency at the moment corresponding to the phase of top sensitivity of the transformer, and in the same frequency and phase that the vibrations from said transformer have at this very moment. Also submitted is the installation drawing needed for implementing the described device.
Abstract:
Methods of mitigating current overload of an ultrasonic system having an ultrasonic stack under load at startup are provided. The methods include beginning an ultrasonic cycle in the ultrasonic system having the ultrasonic stack that runs a closed loop phase control through the weld cycle by ramping up the power of the ultrasonic stack under load. During ramping up of the power of the ultrasonic stack under load, a controller lowers the phase to a negative phase. After ramping up the power of the ultrasonic stack under load is complete, the controller raises the phase to 0 degrees and the ultrasonic stack is operating at steady state and with the phase at 0 degrees.
Abstract:
There is disclosed a sonotrode (1) comprising: a head (15) which defines a sealing surface (14) elongated along a first direction (A) orthogonal to a second direction (B) and at least one first slot (23, 27) which extends through head (15) transversally to said first direction (A); first slot (23) extends parallel to a third direction (C; D) inclined to both first direction and second direction (A, B); first direction (C; D) defines a acute angle (a, p) with second direction (B).
Abstract:
The method of controlling a linear vibration welding apparatus, in accordance with the invention, may comprise the steps of: fastening a first workpiece portion in a fixed position; fastening a second workpiece portion to a reciprocating member; energizing a first single winding magnet with direct current power to create a magnetic field; sensing a location of the reciprocating member with respect to a zero point; and energizing a second magnet when the reciprocating member has crossed the zero point when moving towards the first magnet. The linear vibration welding apparatus in accordance with the invention may comprise: a frame; a flexure array; a first magnet assembly; a second magnet assembly; a digital controller; and direct current amplifiers for powering the magnet assemblies.
Abstract:
Die Erfindung betrifft eine Torsionssonotrode mit zwei einander gegenüberliegenden Stirnseiten (S1, S2) und einer eine Torsionsachse (T) umgebenden Umfangsflache (U), an der zumindest eine Arbeitsfläche (A1, A2, A3, A4) in einem radialen Abstand von der Torsionsachse (T) vorgesehen ist.
Abstract:
The method of controlling a linear vibration welding apparatus, in accordance with the invention, may comprise the steps of: fastening a first workpiece portion in a fixed position; fastening a second workpiece portion to a reciprocating member; energizing a first single winding magnet with direct current power to create a magnetic field; sensing a location of the reciprocating member with respect to a zero point; and energizing a second magnet when the reciprocating member has crossed the zero point when moving towards the first magnet. The linear vibration welding apparatus in accordance with the invention may comprise: a frame; a flexure array; a first magnet assembly; a second magnet assembly; a digital controller; and direct current amplifiers for powering the magnet assemblies.
Abstract:
The invention utilizes a multiple frequency ultrasound generator (12) driving a multiple frequency harmonic transducer (17, 18, 19 ) to improve cleaning and processing effects while eliminating damage to parts being cleaned. An AC switch and circuitry to modify the output of an ultrasound generator in combination with techniques such as random AM and FM signals are used to produce ultrasound waves that have no single frequency components which eliminates exciting parts being cleaned into resonance.
Abstract:
An ultrasonic processing method is disclosed wherein during the processing time interval the motional amplitude and engaging force of the resonating horn (20) and thereby the power and engaging pressure to the workpiece (24) is varied to improve weld strength and decrease weld cycle time. The variation in motional amplitude and engaging force may be in response to a process condition such as a change in dimensions of the workpiece, a sharp rise in the transducer power curve, or in response to the lapse of a predetermined time interval.
Abstract:
Die vorliegende Erfindung betrifft eine Vorrichtung zum Ultraschallbearbeiten von Materialien mit einem Ultraschallbearbeitungssystem bestehend aus einem Ultraschallgenerator, einem Konverter (12), einer Sonotrode (16) sowie einem Gegenwerkzeug (18), wobei Sonotrode (16) und/oder Gegenwerkzeug (18) eine im Wesentlichen zylinderförmige Siegelfläche mit mindestens einer Erhebung (45) aufweist und drehbar ist, so dass sich die Erhebung (45) während der Bearbeitung um die Drehachse dreht und während einer Siegelzeit mit der Materialbahn (20) in Berührung kommt, wobei eine Regeleinrichtung (24) für den Ultraschallgenerator vorgesehen ist, welcher eine Rückführgröße aus dem Ultraschallbearbeitungssystem zugeführt wird und die daraus eine Stellgröße ermittelt und dem Ultraschallgenerator zuführt, wobei eine Prozessgröße aus dem Bearbeitungsprozess ermittelt wird und mit der von der Regeleinrichtung (24) ermittelten Stellgröße vor der Zuführung zum Ultraschallgenerator verknüpft wird. Um eine verbesserte Vorrichtung zum Ultraschallbearbeiten von Materialien mit einem Ultraschallbearbeitungssystem bereitzustellen, ist daher eine Triggereinrichtung (44) vorgesehen, welche die Position der Erhebung (45) bestimmt und eingerichtet ist, um in Abhängigkeit von der Positionsbestimmung die Verknüpfung der Prozessgröße mit der Stellgröße zu gestatten oder zu verhindern.