Minebea Company, Limited

Minetea Co., Ltd.

Piezomotor Uppsala Aktiebolag

Guido Schmid

Stefan Johansson

Stefan Schwamberger

Vladimir Vladimirovich Popov

Norbert Irmer

Olaf Winterhalter

Martin Bauer

Hubert Hauser

Martin Engesser

Thomas Fuss

Carsten Etling

Hermann Flammer

Rudolf Neumann

Jürgen Fleig

Matthias Wildpreth

Helmut Schneider

Ullrich Kreiensen

Martin Arnold

Mathias Wildpreth

Martin Willmer

Thomas Trietz

Bernhard Blocher

Holger Schoenfelder

Eduard Hudec

Martin Wilmer

Anders Larson

The invention relates to a spindle motor having a fluid dynamic bearing system comprising axial and radial bearings that contains a rotor component () which encloses a stationary shaft (), which in turn is connected at both its ends to axially aligned bearing parts () that are fashioned such that they form capillary sealing gaps (), a recirculation channel () filled with bearing fluid that connects the remote regions of the bearing to each other, and an electromagnetic drive system () for driving the rotor component.

Spindle motor having a fluid dynamic bearing system and a stationary shaft

The invention relates to a magnetic axial bearing for taking up axial forces that act on a rotor component that is rotatably supported about a rotational axis with respect to a stator component. The bearing comprises a first bearing part consisting of at least one permanent magnet and at least two flux guide elements associated with the permanent magnet that are disposed on opposing end faces of the permanent magnet and aligned substantially radial and perpendicular to the rotational axis, and a second bearing part consisting of at least two flux guide elements that are disposed at a mutual spacing to one another and aligned substantially radial and perpendicular to the rotational axis, each flux guide element of the second bearing part being associated with a flux guide element of the first bearing part and lying directly opposite the latter in a radial direction and separated from it by an air gap. The invention further describes a spindle motor having a magnetic axial bearing of this kind, used, for example, for driving a hard disk drive.

Magnetic axial bearing and a spindle motor having this kind of magnetic axial bearing

A directly coupled linear drive having a drive unit and a sliding element that are disposed in a frame, the sliding element, actuated by the drive unit, being capable of effecting a movement in a direction of translation with respect to the frame and having a blocking device for blocking the sliding element in the frame in the event of a shock load to the sliding element, the blocking device having a body coupled to the sliding element that absorbs the shock load and is disposed such that the shock load of the body counteracts the shock load of the sliding element.

Linear drive having shock compensation

A dosing system to dispense a predetermined quantity of a fluid medium comprises a digital signal processor control having an interface to emit a start signal and a stop signal and an interface to measure a sensor signal. A dispenser is provided that is triggered by the start signal and the stop signal and, in the interval between the two signals, dispenses a specific quantity of fluid, as well as a sensor unit which, triggered by the start signal, continuously measures the flow rate of the fluid fed to the dispenser and emits a sensor signal as a function of this flow rate. The digital signal processor control measures the sensor signal, determines the quantity of fluid dispensed by the dispenser from this signal and sends a stop signal to the dispenser when the quantity of fluid dispensed by the dispenser corresponds to the predetermined quantity of fluid.

Dosing systems for fluid media

The invention relates to a hydrodynamic bearing arrangement for an electric motor, particularly for a spindle motor to drive the platters of a hard disk drive. The bearing arrangement comprises a shaft, a bearing bush and a thrust plate disposed fixedly on the shaft, the shaft and the thrust plate rotating with respect to the bearing bush, grooved patterns to generate fluid-dynamic pressure being provided on the thrust plate and/or the surfaces located opposite the thrust plate of the bearing sleeve and/or the cover plate. The grooved pattern comprises a number g of grooves distributed over the surface of the bearing sleeve, the thrust plate or the cover plate, wherein in the shaft and/or in the thrust plate, a number h of holes and/or recesses are provided at the inner edge of the thrust plate and/or at the outer edge of the shaft. According to the invention, the number g of grooves cannot be integrally divided by the number h of holes and likewise that h cannot be integrally divided by g.

Hydrodynamic bearing arrangement for an electric motor

A method for filling the bearing gap of a hydrodynamic bearing with a lubricant, where drops of lubricant are produced in a defined manner and are applied to a defined region of the bearing to be filled.

Method and apparatus for filling the bearing gap of a hydrodynamic bearing with a lubricant

A fluid dynamic bearing assembly including a shaft and a bearing sleeve. A bearing gap is formed between the shaft and the bearing sleeve and is filled with a lubricating fluid. A capillary seal is formed at one end of the bearing sleeve, and a recess is formed in the shaft immediately above the capillary seal. The surface of the recess forms an acute angle with an axis of the shaft.

Fluid dynamic bearing having an acute-angled shaft recess

The method and a device to measure the repeatable and non-repeatable runouts of a rotating component of a spindle motor with the aid of at least one probe measuring changes in the distance between the probe and the rotating component depending on the angle of rotation. The probe records a first test signal in a first test cycle from which a signal defining the RRO is determined and stored. In a second test cycle, a command signal proportional to the amplitude and phase of the RRO signal is generated and fed to an electromechanical actuator supporting the probe. Depending on the command signal derived from the first test signal, the actuator changes the distance between the probe and the outer perimeter of the rotating component, thus compensating the runout defined by the RRO signal, while the probe records a second test signal defining the NRRO.

Method and device for measuring the repeatable and non-repeatable runout of rotating components of a spindle motor

A torque measuring device for electric motors having a rotor and a stator is proposed, said apparatus comprising a holding apparatus to hold the stator non-rotatably, an eddy current brake device which can be used to brake the rotor and a torque sensor connected to the eddy current brake device.

Torque measuring device for electric motors and method to measure the torque of an electric motor

A measuring method to determine the noise emission of an electric motor is proposed in which the vibrational excitation of the running electric motor is measured by a laser vibrometer device and this measured vibrational excitation is correlated with a noise level.

Measuring method to determine the noise emission of an electric motor and measuring device

To provide a measuring method on an electric motor with a rotor and a stator for determining the fly height and/or axial play, the rotor being mounted, and in particular fluid-mounted, on the stator, with which method the axial position of the rotor in relation to the stator can be determined with high levels of accuracy and reproducibility, it is provided that the electric motor is operated at a defined measuring speed, at which the rotor is in a specific axial position in relation to the stator, with this relative axial position being determined in that the rotor is brought in a defined manner, with the motor at a standstill, into a first stop position in relation to the stator, in that the rotor is brought in a defined manner, with the motor at a standstill, into a second stop position in relation to the stator, lying opposite the first stop position, and in that the relative axial position between the rotor and the stator is respectively measured in the two stop positions.

Measuring method on an electric motor and measuring device for an electric motor for determining the fly height and/or axial play

In order to improve a method to determine the lubricant filling degree of a fluid bearing in which the bearing gap of the fluid bearing is illuminated and the luminous reflectance is analyzed so that the filling degree can be determined in a simple and reproducible manner, it is provided that a spatial intensity profile of the reflected light is recorded.

Method to determine the lubricant filling degree of a fluid dynamic bearing

A device for measuring torque on an electric motor, which has a first motor portion and a second motor portion, which are rotatable in relation to each other, is proposed, the device comprising a rotatable holding plate for receiving the first motor portion, by means of which plate a rotational movement of the first motor portion in relation to the second motor portion can be driven, and a holding device for the second motor portion for holding the second motor portion in a rotationally fixed manner, the holding plate being disposed and formed in such a way that, when external forces are exerted on the electric motor via the holding device, the electric motor can position itself in relation to the holding device in such a way that external forces influencing the torque measurement are minimized.

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Triberg, Germany

Guido Schmid