Abstract: The electric motor is equipped with an electronic control, for example in the form of a frequency converter (2) and comprises at least one Seebeck element (6) whose one side is connected to the motor (1) in a heat-conducting manner and whose other side is in heat-conducting connection with a cooling medium. The electrical output power of the Seebeck element (6) is led to the electronic control (2) of the motor (1).

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: 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 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.

Abstract: The centrifugal pump unit includes a flow switch arranged within the pump housing in the flow path of a delivery fluid, which essentially consists of an electromagnetic switch device and a two-armed, pivotably mounted lever whose one arm projects into the flow path and whose other arm carries a magnet which is in contact-free active connection with the switch device. The switch device is arranged within a terminal box mounted on the unit housing. The lever is seated within a switch housing which is incorporated in a cartridge-like manner into the pump housing and which is hermetically sealed to the outside and which is arranged neighbouring the terminal box that such it is only in magnetic active connection so that the reed contact located in the terminal box is controlled by the magnet located in the switch housing. In this manner a usual terminal box may be used which does not need to be sealed with respect to the delivery flow.

Abstract: The method for controlling a voltage/frequency converter controlled single-phase or polyphase electric motor evaluates the phase shifting between the EMF and BEMF by way of the deviation between the zero crossing of the phase current and the voltage produced by the intrinsic induction and readjusts the frequency of the converter accordingly. The measurement of the intrinsic induction is effected in the zero crossing of the current courses of the associated phase, wherein during the measurement the phase is separated from the supply network.

Abstract: The wet-running submersible motor comprises a shaft and an electrical rotor arranged thereon, both being arranged in the rotor space of the motor. The shaft is formed hollow either on its longitudinal section on the pump side or over the whole length. On the pump side the shaft surrounds a sealing formation for sealing the rotor space of the motor with respect to the pump. Furthermore the hollow shaft is provided with radial flow passages in order to circulate fluid in the rotor space of the motor. Through the hollow shaft fluid is also led to the pump side, for which the shaft end on the pump side is provided with a fluid passable functional unit. The functional unit is formed so that it at least allows a fluid flow towards the pump side in order to bleed the rotor space and to reduce excess pressure in the rotor space which is subsequently filled with delivery fluid via the sealing formation, by way of fluid exit towards the pump side.

Abstract: The invention relates to a pressure or differential pressure sensor comprising a membrane with at least one measuring element located thereon, as well evaluation electronics for measuring the membrane deflection. The membrane is covered against environmental influences with a protective layer and is gripped within a mounting in a pressure tight manner. The protective layer is composed of a fluid tight amorphous metal layer, a so called metal glass layer which with the interposing of an electrically insulating layer, is directly deposited onto the membrane, the measuring element located thereon and where appropriate, onto further electronic components located thereon. In this manner, on the one hand, the membrane is protected but on the other hand it may be deflected sensitively since the amorphous metal layer is fluid and gas tight even with layer thicknesses in the .mu.m region.

Abstract: The invention relates to an electronic component manufactured in thick film technology, thin film technology or silicon technology and then provided with an electrically insulating layer which is covered by an amorphous metal layer. The amorphous metal layer protects the component, even with the smallest of layer thicknesses, from external influences and directly transmits heating and force effects.

Abstract: A submersible motor unit comprises an electrical drive motor, an electrical control means for setting the rotary speed and/or the torque of the motor, a common heat-conducting housing for the motor and the control means as well as a connection cable electrically connected to the control means wherein this means is provided on the end side of the motor distant to the pump. In particular for an improved disposal, repair and cooling of the submersible motor unit the electrical control means is formed as a cartridge-like constructional unit which can be inserted into the common housing and which can be electrically plug connected to the drive motor, and the housing of the control means connected to the unshielded connection cable bears with its outer circumferential surface on the inner circumferential surface of the common housing.

Abstract: The single-phase induction motor has a starting device which is activated during the start-up phase of the motor and exposes at least a part of the motor coil to a voltage which changes temporarily, the average value of the voltage formed during one period of oscillation not being equal to zero.