Abstract: There is described a roller drive and a roller transport device equipped with the roller drive. The roller drive comprises an electric machine and ends, wherein at least one end has a heat-conducting end contact face. The contact face is intended for coming into heat-conducting contact with a side cheek of the roller transport device. This allows the cooling to be improved. Furthermore, the roller drive can also be designed in such a way that it has a device for accommodating electrical components, wherein the device is intended as a torque support for the electric machine. A regulating device and/or a communication device can also be integrated into the device.

Abstract: The invention relates to a method for determining the angular position (theta) of a rotor (2) pertaining to an electric motor (1) and comprising a number of pairs of poles. Said method consists of the following steps: a pulse pattern (PM1,PM2,PM3) with a pulse duration (T) flows through at least one stator coil (7) of the electric motor (1), such that the rotor (2) does not rotate by more than 90 DEG, divided between the number of pairs of poles, during the pulse duration (T); the angular acceleration (alpha) of the rotor (2), caused by the pulse pattern flowing through the at least one stator coil, (7) is detected; and the angular position (theta) of the rotor (2) is determined by means of the correlation between the flow through the stator coil (7) and the angular acceleration (alpha) of the rotor (2).

Abstract: Two sensors scan a measuring scale, which can be displaced in relation to the sensors and comprises a plurality of equidistant measuring gradation, and deliver corresponding measuring signals. The measuring signals are periodic during a uniform relative displacement of the measuring scale, essentially sinusoidal and essentially phase-shifted by 90° in relation to one another. They have an essentially identical amplitude and a base frequency that corresponds to the relative displacement of the measuring scale. During a delivery period of measuring signals, the measuring scale carries out a relative displacement through one measuring gradation. Corrected signals are determined from the measuring signals using correction values. A signal of the position of the measuring scale in relation to the sensors is determined in turn using said correction signals.

Abstract: Two analog signals are substantially sinusoidal and out-of-phase by about 9020 relative to each other when an element moves in a temporally uniform manner in relation to a stationary element. The two analog signals make it possible to determine the actual position of the moving element relative to the stationary element. The analog signals have a corresponding maximum frequency when the moving element moves at a maximum speed. The signals are detected by sensor units and are fed to AD converters which digitize the signals at a scanning frequency and feed corresponding digital signals to an evaluation block that is configured as a hardware circuit, the scanning frequency of the AD converters being more than twice as large as the maximum frequency. The digital signals are fed to a computing block within the evaluation block, said computing block calculating an arc tangent that corresponds to the digital signals in real time.

Abstract: A measuring element and a measuring method for determining a position are disclosed which use a track with a material measure that is scanned by at least two sensors. The material measure is embodied in such a way that the sensors generate a modulated sinusoidal trace signal as an output signal for determining the position. In this way, the invention provides a simple measuring element and a simple measuring method for determining a position, especially an absolute position.

Abstract: The invention relates to a method for determining the angular position (theta) of a rotor (2) pertaining to an electric motor (1) and comprising a number of pairs of poles. Said method consists of the following steps: a pulse pattern (PM1, PM2, PM3) with a pulse duration (T) flows through at least one stator coil (7) of the electric motor (1), such that the rotor (2) does not rotate by more than 90 DEG, divided between the number of pairs of poles, during the pulse duration (T); the angular acceleration (alpha) of the rotor (2), caused by the pulse pattern flowing through the at least one stator coil, (7) is detected; and the angular position (theta) of the rotor (2) is determined by means of the correlation between the flow through the stator coil (7) and the angular acceleration (alpha) of the rotor (2).

Abstract: The invention relates to a current-controlled converter and a method for controlling a converter of this type (U) comprising three phase outputs (R, S, T). The method comprises the following steps: a) application of a test current signal (ip) to a first (R) and a second (S) phase output of the three phase outputs (R, S, T) and isolation of the third phase output (T), when the converter (U) is activated for operation; b) respective measuring of the test signal (ip) and generation of a measuring signal (imR, imS) that is proportional to the measured test signal (ip) for both the first (R) and the second (S) phase output; c) determination of a correction value (?g1) that is dependent on said measuring signals (imR, imS); and d) control of the converter (U) in accordance with the determined correction value (?g1). The inventive method is used in particular in a converter for controlling a three-phase motor (M).

Abstract: Two sensors scan a measuring scale, which can be displaced in relation to the sensors and comprises a plurality of equidistant measuring gradation, and deliver corresponding measuring signals. The measuring signals are periodic during a uniform relative displacement of the measuring scale, essentially sinusoidal and essentially phase-shifted by 90° in relation to one another. They have an essentially identical amplitude and a base frequency that corresponds to the relative displacement of the measuring scale. During a delivery period of measuring signals, the measuring scale carries out a relative displacement through one measuring gradation. Corrected signals are determined from the measuring signals using correction values. A signal of the position of the measuring scale in relation to the sensors is determined in turn using said correction signals.

Abstract: Two analog signals are substantially sinusoidal and out-of-phase by about 90° relative to each other when an element moves in a temporally uniform manner in relation to a stationary element. The two analog signals make it possible to determine the actual position of the moving element relative to the stationary element. The analog signals have a corresponding maximum frequency when the moving element moves at a maximum speed. The signals are detected by sensor units and are fed to AD converters which digitize the signals at a scanning frequency and feed corresponding digital signals to an evaluation block that is configured as a hardware circuit, the scanning frequency of the AD converters being more than twice as large as the maximum frequency. The digital signals are fed to a computing block within the evaluation block, said computing block calculating an arc tangent that corresponds to the digital signals in real time.

Abstract: A low-wear sensor with little structural outlay to detect a combined linear and rotational movement, such as in a print roller (10). In one embodiment, a PLCD (Permanent Magnetic Linear contactless Displacement) sensor includes a magnet (5) which can be rotated about a longitudinally extended coil (2). A ring magnet is particularly suitable for this. The linear position of the ring magnet can be determined independently of its rotational movement (7) by means of the voltage induced in coils (3,4). Detection of the linear position is contactless and thus wear-free.

Abstract: A low-wear sensor with little structural outlay is proposed to detect a combined linear and rotational movement. A PLCD sensor is provided for this purpose, the magnet (5) of which can be rotated about the longitudinally extended coil (2). A ring magnet is particularly suitable for this. The linear position of the ring magnet can be determined independently of its rotational movement (7) by means of the voltage induced in the coils (3, 4). Detection of the linear position is contactless and thus wear-free.

Abstract: A current sensor using the compensation principle, in particular for measuring direct and alternating currents, includes an entirely digital evaluation circuit for signal processing. This substantially lowers the cost of the control electronics, in particular through integration in an ASIC. The magnetic field probe is, for example, supplied with a square wave voltage of a predetermined frequency, the probe signal is recorded by one or two comparators and the pulse width is digitally measured by counters. Furthermore, the conventional analog final stage for the compensation current is replaced by a PWM end stage with a series connected sigma-delta modulator. The square wave can be synchronized with a defined synchronization signal, which can be derived, for example, from the processed measurement values.

Abstract: A controlled drive circuit for an analog controlled power semiconductor includes a digitally operating logic module, which has a control input receiving control signals from an A/D converter and a control output supplying processed control signals to a D/A module that converts the processed digital control signals signal to an analog or quasi-analog control variable that controls the power semiconductor.

Abstract: A controlled drive circuit for an analog controlled power semiconductor includes a digitally operating logic module, which has a control input receiving control signals from an A/D converter and a control output supplying processed control signals to a D/A module that converts the processed digital control signals signal to an analog or quasi-analog control variable that controls the power semiconductor.