Abstract: A handheld extruder welding device is provided for welding thermoplastic synthetic materials by means of an extrusion screw with a feed zone and a conveying/plasticizing zone. In the area of the feed zone, a feed channel with a ridge running in longitudinal direction is located in a sleeve. This ridge prevents the inserted plastic welding wire from twisting and looping inside and especially outside the handheld extruder welding device.

Abstract: A method and device allows dynamic mask welding with online position adjustment in the high-speed welding of structured and endless plastic films. By a transparent driven mask roller provided with masks being arranged in a passive pressure roller surrounding the mask roller, detection can take place optically, and the mask roller and consequently the mask are synchronized with the film speed. Adjustment is detached from a film transport mechanism and does not influence the welding process and in this case, above all, the speed. High film transport speeds in the range of up to 1000 mm per second can be employed.

Abstract: Microtechnologically prepared component as a flow cytometer. The component contains a preparation area to specifically influence and separate the particles, preferably by dielectrophoresis, a measuring channel area for characterizing the particles, and a sorting area for sorting the particles identified in the measuring channel area by dielectrophoresis. The sorting includes switching elements which permit active guidance of the particles into two or more subchannels corresponding to the criteria which have been registered in the measuring channel area. With a component configured in this way for the use of a flow cytometer, quick and precise sorting of particles, in particular biological cells in a suspension, can be implemented.

Abstract: A method and apparatus for simultaneously heating materials, in particular for welding plastic components, having an arbitrary shape of a flat heating contour by laser radiation is provided. The apparatus has, an appropriate optical arrangement that is used to convert a laser beam into an annular laser beam and focus it onto the end wall of a light-guiding tube and couple it in. At an exit end, the tube is deformed in accordance with the desired heating contour such that the emerging laser beam has this heating contour.

Abstract: A method for joining workpieces by welding with laser light, in which a plurality of workpieces are arranged between a lower pressure plate and a translucent upper pressure plate on a multiplicity of supporting segments movable in a vertical direction, whereby the workpieces are subsequently exposed through the upper pressure plate to a laser beam. The workpieces on the supporting are pressed together and towards the upper plate with a prescribed contact pressure, the spacing of the supporting segments from the upper pressure plate being set variably and independently from each other. A device for joining workpieces by welding with laser light, comprises at least one upper pressure plate of transparent material and a lower pressure plate with multiplicity supporting segments for the workpieces. The supporting segments are arranged side by side on the lower plate and are movable in a vertical direction by compressed air and can be set independently from each other.

Abstract: Method and apparatus for heating plastic by laser beams with the aid of a number of laser points on the focal plane, the laser points being produced by an optical arrangement with the aid of a multiple wedge plate. The arrangement can be integrated in a processing head.

Abstract: A method for joining workpieces made from plastic, the upper workpiece, facing a laser source, consisting of a material transparent to the laser beam, and the lower workpiece consisting of a material absorbent to the laser beam, such that the mutually bordering contact surfaces for the two workpieces melt and are joined to one another under pressure during a subsequent cooling, the guiding of the laser beam onto the site to be joined, and the mechanical compression of the workpieces being carried out simultaneously by a machining head. The corresponding device comprises a machining head with focussing devices for the laser beam onto the contact surface, and pressure-exerting devices for compressing the workpieces. A rotatably mounted glass ball or roller is particularly suitable as pressure-exerting device. The invention permits welding quality to be assured in conjunction with flexibility of the welding operation without expensive and complicated damping balls.

Abstract: An air heater is provided with a connecting case for the power supply and the air to be heated, as well as a heating element attached to the connecting case by means of a carrier. In the connecting housing, the carrier is connected via a plug connection with the connection board for transmitting the heating current. For this purpose, a receptacle angle bracket is provided that can be inserted into the connecting housing and locked in place. The receptacle angle bracket has cylindrical sleeves serving as electrically insulating bushings for the contact pins on the carrier. In order to tap reference voltages for the control device, the contact pins of the plug connection can be connected with the contact tracks of the connection board of the control device by means of rubber-elastic conductive connecting elements.

Abstract: An electric motor having a stator with a plurality of radially arranged pole shoes between which slots are arranged, a rotor which rotates within the stator and has a rotor shaft which is mounted on both sides of the rotor, isolating stars for covering the end faces of the pole shoes, a stator winding which is situated in the slots and surrounds the end-face isolating stars, and an outer stator casing, in which the stator winding uses the isolating stars to secure the rotor and, at the respective end, encloses the rotor bearings and the rotor in its position in the stator. The isolating stars are formed such that they may firstly accommodate the bearings for the rotor shaft and furthermore also may accommodate bearings for attachment of supports for accommodating the electronic circuits for electronic commutation. An electric motor of this type is distinguished by the capability to operate for long periods continuously, accompanied by high rotational speeds and small dimensions.

Abstract: Process and apparatus for joining endless polymer materials by means of the transillumination technique. According to the invention, in order to be joined, the endless materials are guided through two contrarotating rollers that press against each other. The first roller consists of a material that is transparent to laser beams and is tubular. The second roller is formed from a material that can be deformed easily at the surface, so that its surface can adapt to the shape of the first roller. Devices for producing a laser beam at the contact surface between the materials to be joined are arranged in the first roller. In this case, the beam is formed as a linear laser beam longitudinally with respect to the direction of movement of the materials so that during the passage, continuous heating of the material up to the melting point is achieved, without an excessively high laser output having to be provided. By means of the process and the apparatus, continuous joining is possible at high speed.

Abstract: A method for discrimination of particles, preferably biological cells, in a measurement channel having a liquid for transporting the particles by impedance spectroscopy. Pairs of measurement and reference electrodes are arranged in the measurement channel. During movement of a particle through the pair of measurement electrodes, the pairs of measurement and reference electrodes are admitted with same input signals having different frequencies. Measurement values at the measurement and reference electrodes are compared to determine particle specific values for the particle being moved through the measurement channel. The particle specific values for the different frequencies are normalized to a particle specific basic value at a basic frequency; and then the normalized particle specific values are compared with corresponding values of at least one reference particle at the same different frequencies.

Abstract: An automatic welding machine for planar plastic materials, such as sealing sheets, tarpaulins or films, the chassis, in the welding position, in addition to being carried by the driving unit and the pressure device, also being carried by a rigid guide wheel, preferably in the front region of the chassis. With respect to a pressure roller running essentially on the welded overlap region, the guide wheel is arranged in such a way that, during the welding, it runs along the bottom plastic material parallel to the edge of the top plastic material. In addition, the guide wheel has a narrow running surface. During the welding, the guide wheel runs along the edge of the overlapping plastic material and the pressure roller runs essentially on the weld region. Due to this configuration, the automatic welding machine can follow the edge in such a way as to keep to the track, so that guidance by the operator or frequent corrections of the welding direction are not necessary.

Abstract: Hot-air device with a heating element situated in a stream of air, with a carrier consisting of temperature-resistant material and heating wires located in the air channels, and with at least one metal mount for the carrier, wherein the temperature-resistant material of the carrier comes into at least partial electrical contact with the metal mount, and is connected to a device for interrupting the heating circuit, which, during heating, interrupts the heating circuit when a threshold value is reached owing to the measuring current discharged over the insulating material and the contact element. The direct and very quick measuring principle enables a simple and inexpensive protection of the heating element, as well as control and regulation without additional sensors. It is possible to control or regulate the hot-air temperature of the hot-air device via the measuring current.

Abstract: Drive device for a handheld heater unit for welding plastic sealing webs and sheets, which is equipped with a heater device for heating the plastic sealing webs and sheets which are to be welded. The drive device has an elongate housing with a pressure-exerting and driving roller, by means of which the joining force can be applied in the vertical direction with respect to the plastic sealing webs and sheets. Furthermore, there is a coupling unit for joining the housing to the heater unit, in such a manner that the longitudinal axes of the housing and of the heater unit run substantially parallel to one another. In the housing there is a motor, which drives the pressure-exerting and driving roller, the height and/or distance of which with respect to the heater device is adjustable.

Abstract: A process and a device for joining or separating various workpieces, in particular made of plastic or plastic and other materials, by means of curtain-like laser beams. To join workpieces in a particular joining area of the contact surface, a mask, made of a laser-impermeable material, is arranged between the laser source and the workpieces to be joined. The laser beam and the mask are moved relative to each other. To generate high energy density in the joining area, laser beams of at least two diode lasers are brought together, and subsequently, differing laser line lengths are generated by means of a zoom optics arrangement.

Abstract: A method and a device for laser joining of plastics or for joining plastics to other materials, which are brought into contact with pressure, with the workpiece closest to the laser beam source being largely transparent for the laser beam, and the second workpiece being as absorbent as possible. By producing a laser beam shaped in the form of a line on the contact surface between the workpieces and by a relative movement of the laser beam relative to the workpieces, designed according to the desired joint seam structure, the workpieces are bonded together accurately only in the desired joining areas. This permits a highly accurate bonding with the smallest possible joint seam distances, so that even parts for micro-systems engineering can also be produced with a short cycle time.

Abstract: A process and a device for joining or separating various workpieces, in particular made of plastic or plastic and other materials, by means of curtain-like laser beams. To join workpieces in a particular joining area of the contact surface, a mask, made of a laser-impermeable material, is arranged between the laser source and the workpieces to be joined. The laser beam and the mask are moved relative to each other. To generate high energy density in the joining area, laser beams of at least two diode lasers are brought together, and subsequently, differing laser line lengths are generated by means of a zoom optics arrangement. Via a beam splitter, a first laser beam aligned perpendicularly to the surface of the mask, is joined by at least one secondary laser beam arranged perpendicularly to the first laser beam, and the resulting laser beam is directed onto the mask. Laser beams either of different wavelengths or of the same wavelength but of different polarisation are used.

Abstract: A process and a device for joining or separating various workpieces, in particular made of plastic or plastic and other materials, by means of curtain-like laser beams. To join workpieces in a particular joining area of the contact surface, a mask, made of a laser-impermeable material, is arranged between the laser source and the workpieces to be joined. The laser beam and the mask are moved relative to each other. To generate high energy density in the joining area, laser beams of at least two diode lasers are brought together, and subsequently, differing laser line lengths are generated by means of a zoom optics arrangement. Via a beam splitter, a first laser beam aligned perpendicularly to the surface of the mask, is joined by at least one secondary laser beam arranged perpendicularly to the first laser beam, and the resulting laser beam is directed onto the mask.