Abstract: This application relates to computing circuitry (200, 500, 600) for analogue computing. A plurality of current generators (201) are each configured to generate a defined current (ID1, ID2, . . . IDj) based on a respective input data value (D1, D2, . . . Dj). A memory array (202), having at least one set (204) of programmable-resistance memory cells (203), is arranged to receive the defined currents from each of the current generators at a respective signal line (206). Each set (204) of programmable-resistance memory cells (203) includes a memory cell associated with each signal line that, in use, can be connected between the relevant signal line and a reference voltage so as to generate a voltage on the signal line. An adder module (207) is coupled to each of the signal lines to generate a voltage at an output node (210) based on the sum of the voltages on each of the signal lines.

Abstract: A speed control system and a power load balance detector for a turbine is provided. The speed control system includes a speed wheel with a plurality of teeth. A timer stores a time stamp when each of the teeth passes by a speed probe. A first speed estimate is determined for overspeed protection, and a second speed estimate is determined for operational speed control. The power load balance detector trips or shuts down the turbine when an unbalance is above a first threshold and the speed of the turbine is above a second threshold.

Abstract: A Brushless Direct Current (BLDC) motor controller comprises a first terminal for applying a first voltage and a second terminal for applying a second voltage to obtain a driving current for driving a BLDC motor. The BLDC motor controller comprises a remote control unit which is adapted for monitoring a signal which is indicative for a current through at least the first or the second terminal. The BLDC motor controller is adapted for increasing the monitored current by applying an additional current. The additional current is different from zero if the motor is rotating. The BLDC motor controller is adapted for determining whether the motor is rotating or not, based on the monitored signal.

Abstract: A position sensor device comprises at least two Hall elements (11, 12) and a signal evaluation circuit (14) that is coupled on its input side to the at least two Hall elements (11, 12) and is designed to provide a digital position signal (ANS). Moreover, the position sensor device (10) comprises a processing unit (15) comprising a loop filter (16) that is coupled on its input side to the signal evaluation unit (14). The processing unit (15) is designed to adaptively control a filter parameter of the loop filter (16) during operation.

Abstract: An system including a housing defining an enclosure and having an aperture in an exterior surface of the housing; a concave reflector, the reflector being disposed on or in the enclosure of the housing to reflect light emissions; a plurality of solid state light sources disposed within the housing to direct light emissions within the enclosure towards the reflector, the plurality of solid state light sources including multiple groups of solid state light sources; and a mixing chamber defined by a space within the enclosure located between the reflector and the aperture, wherein the reflector is configured to reflect light emissions from the plurality of solid state light sources towards the mixing chamber where the reflected light emissions are to combine before exiting the housing through the aperture.

Abstract: Circuit arrangement including an interface, a protection circuit and a measurement circuit. The interface is configured to receive a signal. The protection circuit is coupled to the interface. The protection circuit is configured to limit a voltage provided by the interface to a protection voltage. The measurement circuit is coupled to the protection circuit and configured to provide at least one of a signal of a first measurement type and a signal of a second measurement type if a voltage provided by the interface is higher than the protection voltage and configured to provide a signal of a second measurement type if the voltage provided by the interface is lower than the protection voltage.

Abstract: A system for determining motor speed of a brush DC motor in an apparatus, including a first filter for receiving a substantially DC component of the motor current and parameters corresponding to the brush DC motor, for calculating a speed estimate thereof; an adaptive bandpass filter having a center frequency corresponding to the speed estimate of the first filter, for receiving the motor current and substantially isolating a periodic current fluctuation thereof; a block for determining a frequency of the periodic current fluctuation, the current fluctuation corresponding to motor speed of the brush DC motor. The adaptive bandpass filter uses debounce filtering to reduce rapid filter passband switching, and a run-in period prior to passband switching to obviate transient effects of filter switching.

Abstract: A management apparatus is described of a rotating motor and a load during power loss; the apparatus comprises a first switching circuit coupled with the rotating motor and a controller of said first switching circuit. The controller is configured to drive the first switching circuit so as to convert a back-electromotive force voltage developed in the rotating motor into a power supply voltage for the load. The first switching circuit is driven in accordance with a first duty cycle. The apparatus comprises a second switching circuit coupled with the load and driven in accordance with a second duty cycle. The controller is configured to vary said first and said second duty cycles to keep the power supply voltage for the load above or equal to a threshold voltage.

Abstract: A method for estimating a rotor position in an electrical machine is provided. The method is applicable to electrical machines that have magnetic saliency. The method includes extracting the rotor position from a demodulated output signal generated in response to an injected high frequency carrier signal and determining a position error compensation based upon a demodulation delay and a velocity or rotational frequency of the electrical machine. The method also includes estimating the rotor position by applying the position error compensation to the extracted rotor position.

Abstract: A brushless motor driven by a sensorless driving circuit includes a rotating body capable of being rotated about a center axis; a rotor magnet arranged coaxially with the rotating body; a stator disposed opposite the rotor magnet; and at least one coil wound around the stator. The brushless motor is driven according to a signal containing a third harmonic component relative to a fundamental wave component in an induced electromotive force. Further, an amplitude ratio of the third harmonic component to the fundamental wave component in the induced electromotive force generated in the coil preferably is about 1% or higher.

Abstract: The present invention provides a motor drive apparatus which improves a trade-off relation between a stable position detection and noise at its driving. A sensorless drive operation circuit calculates by operation a zero cross point (point p) of a voltage of a position detection phase at the next interval, using time information measured based on an output signal from a comparison circuit at the previous interval and the present interval. After the point p has been calculated, points a and b are detected by interrupting a predetermined time drive current.

Abstract: A phase locked loop (PLL) circuit includes a first signal detector having a first input terminal configured to receive a varying first input signal, a second input terminal configured to receive a feedback signal that corresponds to the center of the input frequency, and an output terminal configured to provide an output signal corresponding to a phase difference between the first input and feedback signals. A delay estimator has an input terminal configured to receive the output signal from the first phase detector and in response thereto, output a phase difference estimation signal. A variable delay circuit has an input terminal configured to receive the phase difference estimation signal and in response thereto, phase shift the second input signal.

Abstract: In a voltage signal converter circuit, a peak hold circuit, which is configured with an operational amplifier, a diode, and a capacitor, receives a sensor voltage signal and outputs a peak voltage signal. A bottom hold circuit, which is configured with an operational amplifier, a diode, and a capacitor, receives a sensor voltage signal and outputs a bottom voltage signal. An intermediate voltage signal generator circuit receives the peak voltage signal and the bottom voltage signal and generates an intermediate voltage signal having an intermediate value between a peak voltage value and a bottom voltage value. A comparator generates an accurate rectangular wave voltage signal having a duty ratio equal to 50% in accordance with a magnitude correlation between a sensor voltage value and an intermediate voltage value.

Abstract: An illumination apparatus provides an output with high spatial uniformity of luminance. The illumination apparatus includes a cavity that has reflective surfaces and an output area. At least one light source is disposed in the cavity, with the light source including a point source (such as an LED) and an optical diverter having a flared (e.g., cuspated) reflecting surface. Light from the point source is distributed by the optical diverter towards the reflective surfaces within the cavity. Before exiting the device, light passes through an optical conditioning element that is positioned over the output area of the cavity. The optical conditioning element includes at least a diffuser, such as a translucent film or plastic sheet, and preferably also includes one or more prism sheets such as a brightness-enhancing film.

Abstract: A system for an automatic brake intervention control in an all-wheel-drive vehicle having an automatic brake control system, comprises a control device and separately actuatable brakes which are assigned to the individual wheels. The control device generates signals to control individual brakes as a function of wheel compression and rebounding travels or the wheel reaction forces detected at the individual wheels. Wheel signals are generated which correspond to the wheel suspension travels, the wheel reaction forces or quantities derived therefrom, and the wheel signals are supplied to the control device. The control device generates the signals for controlling the individual brakes at least as a function of the individual wheel signals present as input information.

Abstract: The invention provides an illumination system for a head-mounted display. The illumination system includes a plurality of illuminators which irradiate light over an area. The area has a central region where the light has a selective intensity, and outer regions on opposing sides of the central regions where the light has higher intensities than the selective intensity.

Abstract: A microprocessor controlled apparatus includes a microprocessor (2) with e.g. eight address lines (A,.sub.0,A.sub.1 . . . A.sub.7) on which signals may be applied by the microprocessor for selectively addressing a peripheral device coupled thereto, and a data device such as a LCD module (1) having data lines to which data signals may be applied for transfer into the data device. Four of the data lines (D.sub.0,D.sub.1,D.sub.2,D.sub.3) are coupled to a sub-set of the microprocessor address lines (A.sub.2,A.sub.3,A.sub.4,A.sub.5) excluding the two address lines (A.sub.0,A.sub.1) associated with the least significant bits. The signals on the sub-set of address lines are thus applied as data signals to the data device.

Abstract: The present invention provides a system for controlling the rotational speed of a rotary member such as a video tape recorder drum or the like. The system detects a zero crossing interval in the output of a frequency generator, adding it to the subsequent zero crossing interval in the delayed output signal and using the result to control the motor or the like.

Abstract: A safety device for a tool powered by an electric motor. It has a main switch, electronic controls, and a tachometer-generator. In order to provide a device for switching off a motor as a function of motor speed that is simple and economical and that will retain the same nominal switch-off value for the total life of the device, a relay is wired in parallel with the motor and controls the supply of power to the motor through a relay contact.

Abstract: A device for the production of a tachometry signal of infinite resolution and without ripple from an inductive position sensor. The sensor is fed by a sinusoidal reference signal and supplies two phase signals. A resistance-capacitance circuit tuned to the frequency of the reference signal is fed by the two phase signals of the sensor and supplies a sinusoidal signal whose phase angle is proportional to the rotation of the sensor. This signal is then digitized and processed by digital phase comparators and low-pass filters before differentiation. This includes the use of particular digital phase comparators, each associated with a particular return to zero detector, to produce by a storage flip-flop and an electronic switch, the outgoing tachometry signal with the aid of a single differentiator with a device for elimination of discontinuities.

Abstract: A method and relative circuit in which, signals (sin .phi.M, cos .phi.M) detected by an inductive transducer, supplied by a suitable oscillator, are caused to pass through a RC circuit, to obtain an output signal (VA) out of phase by an angle (.phi.M) proportional to the angle between the polar axis of the rotor and the polar axis of the stator of the transducer, in the case of a rotary detector. Two sets of signals are separately processed: the first set comprises the output signal of the oscillator (fr) and the output signal from the circuit RC (VA); the second set comprises the output signal from the circuit RC (VA) and a signal having the same frequency as the output signal from the oscillator, but out of phase by a fixed angle (F2). Each of these sets, are made to pass through a circuit for detecting the equivalence or not equivalence of the polarity of the input signals, then filtered, derived, in case inverted and then selected by a selecting means to output a tachymetric signal of infinite resolution.

Abstract: A motor speed detector employs a magnetic sensor for detecting rotational movement of rotor armature segments of the motor and for producing real tachometer pulses in response to such movement. False tachometer pulses produced by extraneous non-rotor motor components are discriminated against to produce a signal representative of actual motor rotational speed.

Abstract: A closed-loop system for precisely regulating the speed of an electrically driven rotating body. A tachometer rotor, mechanically linked to the rotating body, is provided with p "teeth " around its periphery. A sensor produces a pulse signal upon passage of each of these teeth, to generate a cyclical tachometer signal having a frequency p times the frequency of rotation. A tachometer counter counts this signal and produces a single output pulse after every n.times.p pulses from the sensor, such that the same one of the p teeth is responsible for triggering each of the successive output pulses, and variations in spacing between teeth do not cause variations in the period of the counter output. A high frequency clock is counted by a second counter, which transfers its count to a storage register and resets upon each pulse from the tachometer counter, such that the count held by the storage register is a continuously updated, highly accurate digital representation of the period of the rotating body.

Abstract: A protective circuit for an electric motor comprises a frequency signal generating circuit for generating a frequency signal in accordance with the rotational speed of the motor, a switching circuit switched over to either permit or cut off supply of current to the motor, and a detecting circuit for detecting that the period of the generated frequency signal has become larger than a predetermined period due to a decrease in the rotational speed of the motor, and cutting off the supply of current to the motor by the switching circuit.

Abstract: An automatic speed control system is disclosed in which an error signal Ve, representing the speed error of the vehicle, is added to a ramp voltage, ramping between fixed values, to produce a control signal Vc. Two comparators compare Vc with upper and lower limits, respectively, so as to produce a pulse train on one of two lines depending on the sign of the error and having a mark-space ratio depending on the magnitude of the error. A circuit responds to the first pulse to occur in the pulse train from one of the two comparators when the vehicle is accelerating towards and overshooting a new desired speed and, via a switching circuit, lowers the upper limit applied to that comparator so as to lengthen the first pulses and help to reduce overshoot of the desired speed. When the vehicle ceases accelerating, the upper limit is switched back to the desired value, and is also switched back to its original setting when the speed falls by a preset amount.

Abstract: A skid control device employs a wheel speed sensor and the control circuit which includes a microcomputer. The microcomputer computes wheel speed on the basis of a pulse signal derived from the wheel speed sensor and delivers a break releasing signal when the wheels slip. A brake control apparatus for controlling the pressure of oil for applying the brakes to the wheels responds to the outputs of the microcomputer. The microcomputer contains a free-running counter which counts clock pulses and a memory containing a sequence of storage locations. This sequence of storage locations stores count values of the free-running counter. A pulse signal from the wheel speed sensor is employed to produce an interrupt request for the microcomputer. The contents of successively adjacent locations in memory are employed by the microcomputer for carrying out the necessary calculations and computing wheel speed.

Abstract: A system for providing signals to a microprocesser-based control from which instantaneous values of speed can be computed includes a wheel-driven alternator which provides an alternating current output whose frequency varies with wheel speed. A signal processor converts this signal to a series of sensor pulses whose width varies inversely with frequency. A sample pulse is supplied from the microprocessor which sets the period or length of time the sensor pulses are examined for each speed calculation of the microprocessor. The sample period pulses are AND gated with a high rate clock and also with the sensor pulses to provide a series of marker pulses marking the up and down excursions of the sensor pulses.

Abstract: Apparatus for monitoring the motion of a movable element, such as a rotatable shaft, comprising sensor means for producing a series of repetitive pulses in response to the motion of the movable element, ramp generator means for producing an increasing ramp signal, the ramp generator means including means for resetting the ramp signal to a starting level in response to each of the pulses, level detector means operable in response to the increase of the ramp signal above a predetermined level, and control means for performing a control function in response to the operation of the level detector means.

Abstract: An overspeed protection system is provided which utilizes simplified construction for detecting overspeed conditions of a rotating device. In the preferred embodiment, a single up/down counter is employed in an overall sequence which includes a first time period during which the counter is counted up from a preselected value by a series of pulse representations of speed for the rotating device. After the expiration of the first time period of the sequence, the counter value is compared to an overspeed limit selected during the previous sequence. If that limit is exceeded, an overspeed condition is detected by the system. In a second time period of the overall sequence, the counter is down counted by the pulse representations of speed. After the expiration of the second predetermined time period of the sequence, the counter value is compared to the original preset value to determine the rate of change in device speed.

Abstract: A brushless tachometer is disclosed which provides a DC output voltage which is a direct function of an instrumented shaft's rotational velocity. The DC voltage is bi-directional, changing sign when the shafts direction of rotation is reversed. The disclosed tachometer preferably utilizes a brushless printed circuit resolver having a large number of poles. The sine and cosine outputs from the resolver are fed to a phase shifting circuit which provides two output signals whose frequencies are related to the speed of rotation of the shaft being instrumented. The frequency of one of the signals increases as the shaft speed increases while the frequency of the other signal decreases as the shaft speed increases. These two signals having frequencies related to shaft speed are fed to frequency to voltage converters. The outputs from the frequency to voltage converters are fed to a differential amplifier whose output is the DC signal which is indicative of the direction and the speed of rotation of the shaft.

Abstract: A system for controlling the speed of a motor vehicle has a speed detector which produces a first electrical signal having a mean level relating to the actual speed of the vehicle and an alternating component whose amplitude is also related to the actual speed of the vehicle. A memory is provided for storing a second electrical signal which has a mean level related to the required vehicle speed and which is substantially free of any alternating component. A comparator compares the first and second electrical signals and therefore produces an error signal which has a mean level corresponding to the difference (if any) between the actual and required vehicle speed and an alternating component related to the actual vehicle speed. A servo responds to the amplitude of the error signal to adjust the actual speed of the vehicle towards the required value.

Abstract: There is disclosed a control circuit which provides a control signal for initiating operation of a glue applicator to cause the applicator to apply glue to a predetermined area on an article moving past the applicator, which circuit automatically compensates for variations in the speed of the article.

Abstract: A vehicle road speed signal source including a speed sensor and a frequency to voltage converter for generating a pulsed output signal having an average magnitude proportional to the road speed of an associated vehicle. The speed sensor has a high energy product magnet attached to the drive shaft of the vehicle which induces current pulses in approximately spaced pick-up coil. The pick-up coil is connected to a preamplifier having a low input impedance to reduce the effect of spurious signals such as ignition noise. The preamplifier output signal may be shaped into a square wave pulse train or may be applied directly to the frequency to voltage converter which generates a pulsed output signal having a duty cycle and therefore an average magnitude proportional to the vehicle road speed.

Abstract: In an anti-skid brake control system for a wheeled vehicle, an electronic circuit for generating a wheel speed signal in accordance with the time duration of a half cycle of a sinusoidal waveform generated by a sensor that detects the presence or absence of teeth of a rotor that revolves with a wheel of the vehicle is arranged so that the measured time duration of both a positive and a negative alternation of the waveform is utilized to obtain accurate wheel skid control at relatively low speeds. Slight differences in the measured time duration of a positive and negative half cycle due to slight variations in the dimensions of a tooth and adjacent space are sensed and modified as required to assure correspondence between the measured time durations in order to avoid false sensing of a wheel skid condition.

Abstract: A wheel speed measuring apparatus is provided for use in an anti-skid brake control system such that a digital speed signal is obtained having good accuracy without resorting to expensive manufacturing methods to assure exact conformity of the teeth and teeth spaces of the rotor member of the wheel sensor device used in the anti-skid control system. The speed measuring apparatus consists of at least two corresponding portions, each consisting of a control unit, a counter and a data register. The control unit of one portion responds to a positive polarity transition of the square wave signal generated by the wheel sensor, while the control unit of the other portion responds to negative polarity transitions, to initiate operation of the respective counters.