Abstract: Disclosed is a method for controlling the firing angle of a signle-phase AC powered electric motor which is triggered by means of at least one locking electronic switch, especially a triac (T1 and T4) located between the distribution voltage (UV) and at least one motor winding (A, B). According to said method, intervals are defined within which the triacs (T2 to T4) are to be fired according to the curve of the distribution voltage (UV) and the voltage (UEMK) induced in the respective winding in order to allow the motor to start as quickly and smoothly as possible and run quietly and at high efficiency.

Abstract: This invention relates to a pressure sensor comprising a diaphragm and at least one measuring element, which is situated on the diaphragm while serving to measure a deflection of the diaphragm. A holding element is placed on at least one surface of the diaphragm in order to accommodate a seal element, whereby this holding element has a through hole, which faces the diaphragm surface while having a cross-section that corresponds to the outer contour of a seal element to be accommodated.

Abstract: The methods serves for activating an electric motor of a metering pump with which the fluid quantity (Vnom) to be delivered is set by an external impulse trigger, wherein a predetermined delivery quantity (Vnom) is allocated to each impulse (t). The control detects the temporal interval (?t) of the two last-received impulses and activates the electric motor such that the fluid quantity to be delivered, taking the previously evaluated interval as a basis, is distributed over the subsequent impulse interval.

Abstract: In a device for biological fluid treatment, fluid is led along surfaces coated with microorganisms, which form parts of disks drivable about a rotation axis. The surfaces are formed by recesses lying in the disks and the disks are arranged to one another such that the leading of the fluid is effected through the recesses, and a recess of one disk is delimited in a channel-forming manner by the adjacent other disk movable relative to this.

Abstract: The method serves for detecting the magnetic flux, the rotor position and/or the rotational speed of the rotor in a single- or multiphase permanent magnet- or -synchronous motor or -generator using the stator voltage equations L·{dot over (i)}?=?R·i?+p·?·?m?+u???Equation (1) L·{dot over (i)}?=?R·i??p·?·?m?+u???Equation (2) It is characterized in that with the evaluations one takes into account the energy conditions of the rotor, by which means one may achieve an accuracy which is considerably greater than known methods.

Abstract: A flow sensor is provided with an obstruction (8) projecting into a flow and at least one measuring probe (10) for measuring a vortex produced by the obstruction (8). The measuring probe (10) includes at least one membrane (12) and a measuring element arranged directly on the membrane (12), for detecting the membrane deflection.

Abstract: The differential pressure sensor is formed of a semiconductor substrate (1) which is thinned out in an inner region into a membrane (2) which may be impinged by pressure on both sides. Measurement resistances (3a to 3d) for detecting the differential pressure (P1 minus P2) are formed within the membrane (2), and compensation resistances (4) are formed on the carrier, which are connected to measurement resistances (3). The measurement resistances (3) are connected into a first measurement bridge (6) and the compensation resistances (4a to 4d) into a second measurement bridge (7).

Abstract: The invention relates to a method for detecting a differential pressure or for correcting a pressure value detected in the fluid on the basis of a pressure of a surrounding medium, wherein at a first point in time the pressure of the surrounding medium is detected and at a later, second point in time the pressure of the fluid is detected, and the pressure value detected in the fluid is corrected on the basis of the pressure of the surrounding medium. The invention furthermore relates to a pump system with a level sensor in which this method is applied, as well as to the use of a pressure sensor in such a pump system.

Abstract: This invention relates to a pressure sensor comprising a diaphragm and at least one measuring element, which is situated on the diaphragm while serving to measure a deflection of the diaphragm. A holding element is placed on at least one surface of the diaphragm in order to accommodate a seal element, whereby this holding element has a through hole, which faces the diaphragm surface while having a cross-section that corresponds to the outer contour of a seal element to be accommodated.

Abstract: The method serves for manufacturing a canned rotor of a permanent magnet motor. Firstly a shaft (2) provided with a rotor core [rotor laminated sheet package] (3) together with a pre-blank (11) forming the later magnet and a [sheet] metal casing (6) surrounding the pre-blank is applied with play into a pressing tool (12). The pre-blank (11) is then deformed by way of end-face pressure impingement such that it then bears with a non-positive fit and over the whole surface on the rotor core [rotor laminated sheet package] (3) and on the [sheet] metal casing (6), wherein the casing (6) is widened radially until its bearing on the pressing tool (12) by way of the radially widening pre-blank (11). After this the magnetisation and hardening is effected, whereupon the free spaces remaining between the [sheet] metal casing (6) and lid (2) are closed by two annular lids, which are tightly connected to the [sheet] metal casing (6) and the shaft (2) with a material fit.

Abstract: The metering pump comprises a synchronous motor which is stepped down via a mechanical gear and the rotation movement of the motor is converted into a stroke movement which drives the membrane pump. To the motor there is allocated an electronic control which may be activated by external impulses with regard to the delivery quantity. At the same time the control operates such that one always passes through a complete operating cycle of the pump if the nominal delivery quantity resulting on account of the received impulses is as large or larger than the quantity which the pump delivers in an operating cycle.

Abstract: A centrifugal pump wherein a threaded ring is secured in its position by way of a pressure body which presses it against the axial abutment of a pump shaft and which is screwed axially to the end of the pump shaft. The threaded ring is seated loosely on the pump shaft and by a thread which is provided in a front hub region of the pump impeller and into which the thread of the threaded ring is screwed.

Abstract: The ready-to-mount axial face seal comprises a rotating unit of a shaft protection sleeve pushable over the pump shaft with a longitudinal section projecting out of the housing of the pump and fastenable to this shaft, with a spring-loaded axial face seal ring surrounding the shaft protection housing and with an elastic sealing ring in the shaft protection sleeve as well as a stationary unit, surrounding the shaft protection sleeve, of a counter ring on which the axial face seal ring bears and of an assembly part for fastening the axial face seal on the pump housing. In relation to the diameter of the pump shaft the wall thickness of the shaft protection sleeve is smaller than with the known shaft protection sleeve. Furthermore the outer diameter of the axial face seal ring and of the counter ring in relation to the same diameter of the pump shaft is an associated standard diameter of an axial face seal without shaft protection sleeve.

Abstract: The invention relates to a method for controlling several pumps in a pump sump, with which each pump comprises a switch which switches on the pump and each pump after its running is first blocked and depending on the running of the further pumps in the pump sump is released again. The invention further relates to a pump for carrying out this method.

Abstract: The method serves for detecting the magnetic flux, the rotor position and/or the rotational speed of the rotor in a single- or multiphase permanent magnet- or -synchronous motor or -generator using the stator voltage equations

Abstract: A centrifugal pump wherein a threaded ring is secured in its position by way of a pressure body which presses it against the axial abutment of a pump shaft and which is screwed axially to the end of the pump shaft. The threaded ring is seated loosely on the pump shaft and by a thread which is provided in a front hub region of the pump impeller and into which the thread of the threaded ring is screwed.

Abstract: The method serves the commutation of an electrically commutated brushless, polyphase permanent magnet motor. The commutation angle, i.e. the angle from the zero crossing of the BEMF signal up to the reapplication of the voltage to the same winding is determined by the angle which results when the winding phase current has reached zero until the zero crossing of the BEMF signal.

Abstract: The ready-to-mount axial face seal comprises a rotating unit of a shaft protection sleeve pushable over the pump shaft with a longitudinal section projecting out of the housing of the pump and fastenable to this shaft, with a spring-loaded axial face seal ring surrounding the shaft protection housing and with an elastic sealing ring in the shaft protection sleeve as well as a stationary unit, surrounding the shaft protection sleeve, of a counter ring on which the axial face seal ring bears and of an assembly part for fastening the axial face seal on the pump housing. In relation to the diameter of the pump shaft the wall thickness of the shaft protection sleeve is smaller than with the known shaft protection sleeve. Furthermore the outer diameter of the axial face seal ring and of the counter ring in relation to the same diameter of the pump shaft is an associated standard diameter of an axial face seal without shaft protection sleeve.

Abstract: The frequency converter is provided for an electric motor and comprises a rectifier, an intermediate circuit and an inverse rectifier which are connected with respect to circuiting technology via a control and regulation circuit. In the inverse rectifier to each motor phase there are allocated at least two electronic switches, one for the side conducting the higher potential and one for the side conducting the low potential. The intermediate circuit is formed as an active intermediate circuit and contains a Buck-Booster converter. It is controlled such that the voltage at the output of the intermediate circuit with respect to magnitude is always smaller than that at the input. By way of this inexpensive components may be used in the inverse rectifier and in particular also in the control and regulation circuit.

Abstract: The method serves the commutation of an electrically commutated brushless, polyphase permanent magnet motor. The commutation angle, i.e. the angle from the zero crossing of the BEMF signal up to the reapplication of the voltage to the same winding is determined by the angle which results when the winding phase current has reached zero until the zero crossing of the BEMF signal.