Abstract:
An AC switch is created by switching devices to modify the output of an ultrasonic generator. The AC switch introduces a modification circuitry into and out of the output stage of the ultrasonic generator. The AC switch is placed in parallel with the modification circuitry when inserting the modification circuitry into a conduction line of the ultrasonic generator. It is placed in series when inserting the modification circuitry between two nodes of the ultrasonic generator. A control circuit is associated with the AC switch to turn on and off the ultrasonic generator, overcoming the inability of triacs to turn off power when conducting ultrasonic current. The introduction of the modification circuitry by the AC switch allows the modification of the frequency, amplitude, power, impedance and waveform of an ultrasonic generator.
Abstract:
An ultrasonic processing method is disclosed wherein during the processing time interval the motional amplitude of the resonating horn and thereby the power to the workpiece is reduced. The reduction in motional amplitude may be in response to a process condition such as a change in dimension of the workpiece or a sharp rise in the power curve, or it may be in response to the lapse of a predetermined time.
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:
A circuit is connected to an ultrasonic transducer being fed by a constant current or constant voltage power supply. By rectifying, differentiating, and amplifying the transducer coil voltage an output signal that is a function of the transducer and load impedance is provided that can be displayed so as to determine the operating condition of the ultrasonic apparatus.
Abstract:
The present invention concerns an ultrasonic vibration system comprising a sonotrode which has two sonotrode end faces and a circumferentially extending lateral surface connecting the two sonotrode end faces together, wherein the sonotrode has an elongate core element and at least one wing element, wherein core element and wing element respectively extend from the one sonotrode end face to the other sonotrode end face in a longitudinal direction, wherein the wing element has a sealing surface which is provided to come into contact with a material for processing thereof and is connected to the core element by way of a plurality of webs spaced from each other in the longitudinal direction of the core element, and a converter which is optionally connected to the sonotrode by way of an amplitude transformer. According to the invention it is proposed that the ultrasonic vibration system is connected to a machine stand by way of a mounting connected to the lateral surface.
Abstract:
The invention relates to a method for joining a sealing seam of a tubular bag packaging by means of an ultrasonic applicator (10), characterized in that said ultrasonic applicator (10) generates ultrasonic waves at a frequency of between 0.1 MHz and 5 MHz, preferably between 0.5 MHz and 2 MHz. The invention also relates to a longitudinal seal joining device of a tubular bag machine for use with said claimed method.
Abstract:
The present invention relates to a device for the ultrasonic processing of materials, which has an ultrasonic processing system, which comprises: an ultrasound generator, a converter (12), a sonotrode (16), and a counter tool (18); wherein the sonotrode (16) and/or the counter tool (18) has a substantially cylindrical sealing surface having at least one elevation (45) and can be rotated such that, during the processing, the elevation (45) rotates about the axis of rotation and comes in contact with the material web (20) during a sealing time, wherein a control apparatus (24) is provided for the ultrasound generator, to which control apparatus a feedback variable from the ultrasound processing system is fed and which control apparatus determines a manipulated variable therefrom and feeds said manipulated variable to the ultrasound generator, wherein a process variable from the processing process is determined and is linked to the manipulated variable determined by the control apparatus (24) before the feeding to the ultrasound generator. In order to provide an improved device for the ultrasonic processing of materials having an ultrasonic processing system, a trigger apparatus (44) is provided, which determines the position of the elevation (45) and is designed to permit or prevent the linking of the process variable to the manipulated variable in accordance with the position determination.
Abstract:
The invention relates to a method for joining a sealing seam of a tubular bag packaging by means of an ultrasonic applicator (10), characterised in that said ultrasonic applicator (10) generates ultrasonic waves at a frequency of between 0.1 MHz and 5 MHz, preferably between 0.5 MHz and 2 MHz. The invention also relates to a longitudinal seal joining device of a tubular bag machine for use with said claimed method.