Abstract:
Disclosed is a method for cleaning aeration elements (1) provided with pores or bores in aerated basins (2) of wastewater treatment plants or water treatment plants. The aeration field (4) formed by the aeration elements (1) and the pipes (3) connecting said aeration elements to each other is completely filled with a cleaning agent in a fluid form by applying pressure that is high enough to send said cleaning agent through the pores or bores of the aeration elements (1). After applying the cleaning fluid on the pores or bores of the aeration elements (1) for a variable amount of time, the aeration field (4) is emptied again. In a further optional cleaning step, the aeration field (4) is cleaned once again with a rinsing fluid, preferably water. Also disclosed are the use of an alkaline cleaning agent with a pH value of at least 10, preferably 12, and advantageous compositions of the cleaning fluid used for cleaning aeration elements.
Abstract:
Disclosed is a method for cleaning aeration elements (1) provided with pores or bores in aerated basins (2) of wastewater treatment plants or water treatment plants. The aeration field (4) formed by the aeration elements (1) and the pipes (3) connecting said aeration elements to each other is completely filled with a cleaning agent in a fluid form by applying pressure that is high enough to send said cleaning agent through the pores or bores of the aeration elements (1). After applying the cleaning fluid on the pores or bores of the aeration elements (1) for a variable amount of time, the aeration field (4) is emptied again. In a further optional cleaning step, the aeration field (4) is cleaned once again with a rinsing fluid, preferably water. Also disclosed are the use of an alkaline cleaning agent with a pH value of at least 10, preferably 12, and advantageous compositions of the cleaning fluid used for cleaning aeration elements.
Abstract:
Es wird ein Aufbaukonzept für Hochdrucksensoren vorgeschlagen, das eine einfache und kostengünstige Herstellung von zuverlässigen Hochdrucksensoren auch für Druckbereiche oberhalb 2200 bar ermöglicht. Ein derartiger Hochdrucksensor (10) umfasst ein Sensorelement (1) zur Druckerfassung und ein Anschlussstück (2) zur Ankopplung des Sensorelements (1) an ein Messsystem, wobei im Grundkörper (11) des Sensorelements (1) eine Membran (13) über einer Sacköffnung (12) ausgebildet ist, wobei im Grundkörper (21 ) des Anschlussstücks (2) ein Druckkanal (22) ausgebildet ist, und wobei das Sensorelement (1) so auf dem Anschlussstück (2) montiert ist, dass die Membran (13) über den in die Sacköffnung (12) mündenden Druckkanal (22) mit einem Messdruck beaufschlagbar ist. Erfindungsgemäß ist die Sacköffnung (12) im Grundkörper (11) des Sensorelements (1) zumindest in einem Abschnitt konisch auf die Membran (13) zulaufend ausgebildet und das dem Sensorelement (1) zugewandte Ende (23) des Druckkanals (22) ist rohrförmig ausgebildet. Dieses rohrförmige Ende (23) des Druckkanals (22) ist in die Sacköffnung (12) eingepresst, so dass die Rohrwandung zumindest in einem Umfangsbereich dichtend gegen die Seitenwandung der Sacköffnung (12) gepresst ist.
Abstract:
Verfahren zur Reinigung von mit Poren oder Bohrungen versehenen Belüfterelementen (1) in belüfteten Becken (2) von Abwasserreinigungs- oder Wasseraufbereitungsanlagen, wobei das von den Belüfterelementen (1) und den sie verbindenden Rohrleitungen (3) gebildete Belüfterfeld (4) mit einem Reinigungsmittel in flüssiger Form und unter Druckverhältnissen, die den Durchtritt der Reinigungsflüssigkeit durch die Poren oder Bohrungen der Belüfterelemente (1) bewirken, vollständig befüllt wird, in einem weiteren Reinigungsschritt nach einer variablen Einwirkzeit der Reinigungsflüssigkeit auf die Poren oder Bohrungen der Belüfterelemente (1) das Belüfterfeld (4) wieder entleert wird und wahlweise in einem weiteren Reinigungsschritt das Belüfterfeld (4) mit einer Spülflüssigkeit, vorzugsweise Wasser, nachgereinigt wird. Erfindungsgemäss wird die Verwendung eines alkalischen Reinigungsmittel mit einem pH-Wert von mindestens 10, vorzugsweise 12, beschrieben. Vorteilhafte Zusammensetzungen der Reinigungslösung zur Reinigung von Belüfterelementen werden vorgeschlagen.
Abstract:
A mechanical structure is disposed in a chamber, at least a portion of which is defined by the encapsulation structure. A first method provides a channel cap having at least one preform portion disposed over or in at least a portion of an anti-stiction channel to seal the anti-stiction channel, at least in part. A second method provides a channel cap having at least one portion disposed over or in at least a portion of an anti-stiction channel to seal the anti-stiction channel, at least in part. The at least one portion is fabricated apart from the electromechanical device and thereafter affixed to the electromechanical device. A third method provides a channel cap having at least one portion disposed over or in at least a portion of the anti-stiction channel to seal an anti-stiction channel, at least in part. The at least one portion may comprise a wire ball, a stud, metal foil or a solder preform. A device includes a substrate, an encapsulation structure and a mechanical structure. An anti-stiction layer is disposed on at least a portion of the mechanical structure. An anti-stiction channel is formed in at least one of the substrate and the encapsulation structure. A cap has at least one preform portion disposed over or in at least a portion of the anti-stiction channel to seal the anti-stiction channel, at least in part.
Abstract:
A sensor for capacitively recording an acceleration has at least two interdigital capacitors (3, 5), each pair of capacitors having electrodes (7, 9) with a plurality of elongated fingers (11) which at least partially mesh with each other. One of the electrodes (9) can be shifted and is coupled to a deflectable seismic mass (13). The invention is characterised in that the electrodes (7, 9) are arranged in such a way that when one electrode (9) is deflected the fingers (11) move in parallel towards each other, their spacing (d) transversely to the direction of deflection remaining substantially constant while their overlapping (1) changes. The two interdigital capacitors are arranged relative to each other in such a way that during acceleration the capacity value of one capacitor increases and that of the other decreases.
Abstract:
There are many inventions described and illustrated herein, as well as many aspects and embodiments of those inventions. In one aspect, the present invention is directed to a resonator architecture including a plurality of in-plane vibration microelectromechanical resonators (for example, 2 or 4 resonators) that are mechanically coupled to provide, for example, a differential signal output. In one embodiment, the present invention includes four commonly shaped microelectromechanical tuning fork resonators (for example, tuning fork resonators having two or more rectangular-shaped or square-shaped tines). Each resonator is mechanically coupled to another resonator of the architecture. For example, each resonator of the architecture is mechanically coupled to another one of the resonators on one side or a corner of one of the sides. In this way, all of the resonators, when induced, vibrate at the same frequency.
Abstract:
The invention relates to a method for producing surface micromechanical structures having a high aspect ratio. At least one sacrificial layer (20) is provided between a substrate (30) and a functional layer (10). Trenches (60, 61) are provided in said functional layer (10) by means of a plasma etching process, said trenches uncovering at least some surface areas (21, 22) of the sacrificial layer (20). According to the invention, a further layer (70) is deposited at least partially on the lateral walls of the trenches, but not on the uncovered surface areas (21, 22) of the sacrificial layer (20), in order to increase the aspect ratio of said trenches. The invention also relates to a sensor, especially an acceleration or rotational rate sensor.
Abstract:
Die Erfindung betrifft ein Verfahren zum Erzeugen von Oberflächenmikromechanikstrukturen mit hohem Aspektverhältnis, bei dem zwischen einem Substrat (30) und einer Funktionsschicht (10) zumindest eine Opferschicht (20) vorgesehen wird, wobei in der Funktionsschicht (10) durch einen Palsma-Ätzprozess Gräben (60, 61) vorgesehen werden, von denen zumindest einige Oberflächenbereiche (21, 22) der Opferschicht (20) freilegen. Erfindungsgemäss ist vorgesehen, dass zur Vergrösserung des Aspektverhältnisses der Gräben zumindest abschnittsweise auf den Seitenwände der Gräben, nicht jedoch auf den freigelegten Oberflächenbereichen (21, 22) der Opferschicht (20), eine weitere Schicht (70) abgeschieden wird. Weiterhin betrifft die Erfindung einen, insbesondere eine Beschleunigungs- oder Drehratensensor.
Abstract:
The invention relates to a method for producing a membrane sensor, especially a thermal membrane sensor, over a silicon substrate (1). A thin layer (4) comprised of silicon carbide or silicon nitride is deposited over an area (2) made of porous silicon which is configured in the surface of the substrate (1). Openings (5, 7) are then formed in said silicon carbide or silicon nitride layer (4), said layer extending to the porous silicon layer (2), by means of a dry etching method. Afterwards, semiconductor and circuit-board structures (6) are implanted in the upper surface of the membrane layer (4) by means of lithographic steps and the sacrificial layer (2) comprised of porous silicon is then removed by a suitable solvent, for example ammoniac. As a result, a cavity (8) is produced underneath the membrane layer (4) which thermally decouples the sensor membrane from the substrate (1).