Abstract: An arrangement for providing a throttle cross-section for a fluid flow. The throttle cross-section can be varied depending on a pressure difference present across the throttle cross-section. The arrangement is designed such that the polarity of the pressure difference, by which the throttle cross-section can be varied and/or changed. It is thereby possible to use the arrangement for fluid flows that alternate in the flow direction thereof.

Abstract: An arrangement for providing a throttle cross-section for a fluid flow. The throttle cross-section can be varied depending on a pressure difference present across the throttle cross-section. The arrangement is designed such that the polarity of the pressure difference, by which the throttle cross-section can be varied and/or changed. It is thereby possible to use the arrangement for fluid flows that alternate in the flow direction thereof.

Abstract: An ultrasonic transducer comprises an elongate horn, a counterpiece, two piezoelectric drives and a screw. The counterpiece is fastened to the horn by means of the screw and thus clamps the piezoelectric drives, which are arranged on either side of a longitudinal axis of the ultrasonic transducer, between the horn and the counterpiece. The ultrasonic transducer is designed in such a way that the tip of a capillary which is clamped in the horn can oscillate in two different directions.

Abstract: An ultrasonic transducer comprises an elongate horn, a counterpiece, two piezoelectric drives and a screw. The counterpiece is fastened to the horn by means of the screw and thus clamps the piezoelectric drives, which are arranged on either side of a longitudinal axis of the ultrasonic transducer, between the horn and the counterpiece. The ultrasonic transducer is designed in such a way that the tip of a capillary which is clamped in the horn can oscillate in two different directions.

Abstract: When mounting semiconductor chips, the semiconductor chips are presented on a wafer table where they are picked one after the other by a pick and place system, transported and placed onto a substrate that rests on a supporting surface of a substrate table. The wafer table is aligned diagonally to the supporting surface of the substrate table whereby part of the wafer table is located under the substrate table. The pick and place system comprises a shuttle with a swivel arm carrying a bondhead. The swivel arm is swivelled back and forth between two predetermined swivel positions whereby in the first swivel position a longitudinal axis of the swivel arm embraces the angle ? with the perpendicular to the supporting surface of the substrate table and whereby in the second swivel position the longitudinal axis of the swivel arm runs orthogonally to the supporting surface of the substrate table.

Abstract: A Wire Bonder comprises a bondhead that can be moved in a horizontal plane that has a capillary clamped to a horn and parts of an image recognition system. The tip of the capillary and the optical axis of the image recognition system are separated by a vectorial distance D. The Wire Bonder has a device with a body with an optical marking and with two stop faces that enable the vectorial distance D to be recalibrated at any time. The control program of the Wire Bonder is set up on the one hand to move the capillary towards the first stop face and to determine a first co-ordinate xC of the position of the bondhead as soon as the capillary touches the first stop face and then to move the capillary towards the second stop face and to determine a second co-ordinate yC of the position of the bondhead as soon as the capillary touches the second stop face.

Abstract: With the mounting of semiconductor chips onto a substrate, the semiconductor chips are presented on a wafer table where they are picked one after the other by a Pick and Place system, transported and placed onto the substrate that rests on a supporting surface of a substrate table. The wafer table is aligned diagonally to the supporting surface of the substrate table whereby part of the wafer table is located under the substrate table. The Pick and Place system comprises a shuttle with a swivel arm that carries the bondhead. The swivel arm can be swivelled back and forth between two predetermined swivel positions whereby in the first swivel position a longitudinal axis of the swivel arm embraces the angle ? with the perpendicular to the supporting surface of the substrate table and whereby in the second swivel position the longitudinal axis of the swivel arm runs orthogonally to the supporting surface of the substrate table. The angle ? lies in the range of 10° to 50°, preferably in the range of 20° to 35°.

Abstract: A Wire Bonder comprises a bondhead that can be moved in a horizontal plane that has a capillary clamped to a horn and parts of an image recognition system. The tip of the capillary and the optical axis of the image recognition system are separated by a vectorial distance D. The Wire Bonder has a device with a body with an optical marking and with two stop faces that enable the vectorial distance D to be recalibrated at any time. The control program of the Wire Bonder is set up on the one hand to move the capillary towards the first stop face and to determine a first co-ordinate xC of the position of the bondhead as soon as the capillary touches the first stop face and then to move the capillary towards the second stop face and to determine a second co-ordinate yC of the position of the bondhead as soon as the capillary touches the second stop face.

Abstract: With a device for the formation of a wire ball at the end of a wire an in and out swivelling electrode with an oblong shape is connected to the shaft of a motor directly or indirectly via a connecting piece so that the electrode is essentially rotated on its longitudinal axis when swivelling in and out. The mass inertia of the electrode is low as regards the rotational axis which is why it can be turned with negligible expenditure of energy. On swivelling in and out, the electrode is turned back and forth between a lower limit position in which a surface necessary for creating the spark, the so-called firing lug is located underneath the capillary of the Wire Bonder and an upper limit position in which the firing lug is located laterally elevated next to the capillary.

Abstract: With a device for the formation of a wire ball at the end of a wire an in and out swivelling electrode with an oblong shape is connected to the shaft of a motor directly or indirectly via a connecting piece so that the electrode is essentially rotated on its longitudinal axis when swivelling in and out. The mass inertia of the electrode is low as regards the rotational axis which is why it can be turned with negligible expenditure of energy. On swivelling in and out, the electrode is turned back and forth between a lower limit position in which a surface necessary for creating the spark, the so-called firing lug is located underneath the capillary of the Wire Bonder and an upper limit position in which the firing lug is located laterally elevated next to the capillary.

Abstract: A Wire Bonder contains a bondhead which comprises a slide, a rotary beam rotatable on a vertical axis and a rocker mounted on the rotary beam. The slide is movable back and forth in a predetermined horizontal direction and moves the rotary beam with it. The slide preferably bears on a horizontally arranged glide plate by means of an air bearing charged with vacuum. The rotary beam also preferably bears on the glide plate by means of a further air bearing charged with vacuum. A drive arranged on the slide is preferably foreseen for the rotating movement of the rotary beam.