Abstract: A load control device may control power delivered from a power source, such as an alternating-current (AC) power source, to at least two electrical loads, such as a lighting load and a motor load. The load control device may include multiple load control circuit, such as a dimmer circuit and a motor drive circuit, for controlling the power delivered to the lighting load and the motor load, respectively. The load control device may adjust the rotational speed of the motor load in a manner so as to minimize acoustic noise generated by the load control device and reduce the amount of time required to adjust the rotational speed of the motor load. The load control device may remain powered when one of the electrical loads (e.g., the lighting load) has been removed (e.g., electrically disconnected or uninstalled) and/or has failed in an open state (has “burnt out” or “blown out”).

Abstract: A circuit structure includes: a network of clamps; sense elements in series with the clamps and configured to sense a turn-on of at least one clamp of the network of clamps; and feedback elements connected to the clamps to facilitate triggering of remaining clamps of the network of clamps.

Abstract: An implant bending device includes a first work surface. An implant support is movable relative to the first work surface. A second work surface is movable relative to the first work surface. A sensor is connected with the work surfaces and configured to detect contact of at least one of the work surfaces with an implant. Systems, surgical instruments, spinal constructs, implants and methods are disclosed.

Abstract: A vehicle including a powertrain system that includes an electric machine electrically connected to a power inverter is described, wherein the powertrain system is operative in an electric vehicle mode to generate propulsion torque. A method for controlling the powertrain system includes determining a vehicle speed, and determining a preferred audible sound to be generated by the powertrain system when operating in the electric vehicle mode at the vehicle speed. A control signal for the power inverter is determined, and is associated with operating the powertrain system in the electric vehicle mode at the vehicle speed. The preferred audible sound is incorporated into the control signal for the power inverter, and the power inverter is controlled to operate the electric machine employing the control signal and the preferred audible sound.

Abstract: A system and method for controlling a speed of a permanent magnet AC motor (38) based on a delay angle of a triac-controlled AC voltage signal (66) from a triac (34). A simulated load (54) connected to the triac (34) enables a load current and creates the signal (66). A first detector (48) detects a zero-crossing point of the AC voltage signal, and a second detector (50) detects a subsequent turn-on instance of the triac (34). A speed command generator (52) measures an interval between the zero-crossing point and the subsequent turn-on instance, and converts the delay angle to a speed command for controlling the speed of the motor (38). The simulated load (54) may include resistors (70) having a resistance which causes the load current to be below a holding current rating of the triac (34), thereby causing the triac (34) to turn off after the interval has been measured.

Abstract: The present invention provides a motor driving device without an additional signal line for identifying whether a motor rotates stably. The motor driving device (21) includes a control circuit (100) for receiving an acceleration signal (SU) and a deceleration signal (SD), and generating a driver control signal (S10); a driving circuit (200) for generating a motor driving signal (S3) according to the driver control signal (S10); and a phase-locked identifying circuit (500) for monitoring an input mode of the acceleration signal (SU) and the deceleration signal (SD), and identifying whether the motor rotation speed is stable at the desired target rotation speed.

Abstract: A load control device for controlling the power delivered from an AC power source to an electrical load includes a thyristor, a gate coupling circuit for conducting a gate current through a gate of the thyristor, and a control circuit for controlling the gate coupling circuit to conduct the gate current through a first current path to render the thyristor conductive at a firing time during a half cycle. The gate coupling circuit is able to conduct the gate current through the first current path again after the firing time, but the gate current is not able to be conducted through the gate from a transition time before the end of the half-cycle until approximately the end of the half-cycle. The load current is able to be conducted through a second current path to the electrical load after the transition time until approximately the end of the half-cycle.

Abstract: The present invention belongs to power generation field. It relates to a method for improving cooling capacity of a power station direct air-cooling system and the cooling system thereof. According to the present invention, a transformer in a cooling system is connected to a voltage of the power grid and outputs a voltage to an electric motor, so that its working voltage reaches 380-390V; a frequency of 40-47 HZ is output from a frequency converter in the cooling system to the electric motor; a fan is driven by the electric motor working under 380-390V and 40-47 HZ to rotate according to a set velocity ratio with the aid of a speed reducer, and cooling wind is delivered by the rotating fan head-on to a heat radiator. The present invention can be widely applied in rebuilding of existing direct air-cooling units, or designing of new power station direct air-cooling systems.

Abstract: A control apparatus for a three-phase brushless motor, in which a control circuit includes time interval calculation means (133 in FIG. 4). The time interval calculation means (133) is endowed with at least one time interval calculation mode. In the time interval calculation mode, pluralities of time intervals which correspond to an addition section obtained by adding up two or more Q continuous sections are calculated on the basis of two position detection signals which lie at both the ends of the addition section, among position detection signals successively generated. The control circuit determines pluralities of energization switching timings on the basis of the pluralities of time intervals. The control apparatus for the three-phase brushless motor can decrease the deviations of the energization switching timings attributed to the errors of the mounting positions of position sensors or to the errors of the magnetized positions of a rotor, without requiring any complicated adjustment.

Abstract: A motor control device includes: a motor that has a plurality of rotors which respectively have a magnetic piece, which drives or supplementarily drives a vehicle; a phase changing mechanism that changes relative phases of the plurality of rotors, and sets these to a predetermined induced voltage constant; and a speed control device that controls a phase changing speed of the phase changing mechanism.

Abstract: A stepping motor controlling device according to the present invention includes lead angle computing means which computes a lead angle according to the load torque current deviation of the stepping motor, adding means which adds an angle command to the lead angle to determine a winding exciting angle and voltage applying means which applies a voltage according to the winding exciting angle to the stepping motor.

Abstract: A delta type inverter is used in conjunction with a closed-loop motor controller to provide a control device for driving a three phase brushless direct current motor. The delta inverter has one-half of the solid state switching devices and diodes required by conventional bridge type inventers, thereby improved reliability, and enabling the motor control device to have reduced size, cost and weight. The closed-loop motor controller may include a torque loop for reducing torque ripple during operation of the motor.

Abstract: Methods and systems for operating a motor coupled to an electrical bus in a vehicle are provided. Selected resonant frequencies of the electrical bus are determined. The selected resonant frequencies include a low resonant frequency and a high resonant frequency. Power is provided to the motor through at least one switch operating at a switching frequency. The switching frequency is controlled as a function of a rate of operation of the motor. The function is characterized by one of a first substantially linear portion having a first slope when the switching frequency is less than or equal to a selected switching frequency and a second substantially linear portion having a second slope if the switching frequency is greater than the selected frequency, the selected switching frequency being greater than the low resonant frequency and a substantially linear portion having a y-intercept being greater than the low resonant frequency.

Abstract: Methods and systems for operating a motor coupled to an electrical bus in a vehicle are provided. Selected resonant frequencies of the electrical bus are determined. The selected resonant frequencies include a low resonant frequency and a high resonant frequency. Power is provided to the motor through at least one switch operating at a switching frequency. The switching frequency is controlled as a function of a rate of operation of the motor. The function is characterized by one of a first substantially linear portion having a first slope when the switching frequency is less than or equal to a selected switching frequency and a second substantially linear portion having a second slope if the switching frequency is greater than the selected frequency, the selected switching frequency being greater than the low resonant frequency and a substantially linear portion having a y-intercept being greater than the low resonant frequency.

Abstract: The invention relates to a drive device for an electric motor, in particular for a brushless DC motor in an electrical tool, which is powered by a rechargeable battery. The drive device has at least one power semiconductor, in particular for controllable application of an electrical voltage to the electric motor, a control circuit for controlling the power semiconductor, and a mounting plate which, for example, is in the form of a printed circuit board. At least one portion of the control circuit, in particular electrical and/or electronic components as well as the conductor tracks (which connect the electrical and/or electronic components) of the control circuit, is arranged on the mounting plate. The power semiconductor is arranged on the mounting plate and/or on a mount element, which is mounted on the mounting plate.

Abstract: A protecting device of a fan system includes at least one first switch element and at least one control unit. The first switch element receives a first input signal. The control unit is electrically connected with the first switch element, receives the first input signal, and controls the first switch element to turn on or turn off according to the first input signal. The control unit stops outputting the first input signal when the first switch element turns on. The control unit outputs the first input signal when the first switch element turns off, so that a fan of the fan system can be driven by the first input signal.

Abstract: A motor control device includes: a motor that has a plurality of rotors which respectively have a magnetic piece, which drives or supplementarily drives a vehicle; a phase changing mechanism that changes relative phases of the plurality of rotors, and sets these to a predetermined induced voltage constant; and a speed control device that controls a phase changing speed of the phase changing mechanism.

Abstract: A rotational speed controller maintains a constant low speed during idling, a constant high speed when a load is applied and controls motor rotational speed in the range between low and high speed to ensure safe operation when used in an electrically powered tool. When the current detection signal output from a current detection circuit is lower than a first predetermined value (during idling), a rotational speed setting circuit outputs a rotational speed setting signal indicating a first rotational speed to drive the motor at a constant low speed. When the current detection signal exceeds a second predetermined value (when a load is applied), the rotational speed setting circuit outputs a rotational speed setting signal indicating the second rotational speed to drive the motor at a constant high speed.

Abstract: The invention relates to a control system for a commutator motor which is operated by phase-fired control. Allocation of a first and second control device in a single operating state without transition makes it possible to obtain constant jolting rotation of said motor by continuously varied cutting of the half-waves into first and second area sections (8,7) of an alternative current voltage. The inventive type of control system can be used advantageously in electric screwing or drilling tools.

Abstract: An active attenuation system for a DC motor which yields global vibration reduction of slot or other motor induced tonals at the plate on which the motor is mounted without modifying the construction of the motor. The system comprises one or more vibration sensors, a signal synchronized to the slot rate or other motor induced tonal rate, an electronic adaptive controller and the means to supply the control signal into the motor field and/or armature current.

Abstract: The motor speed control device of the present invention is provided with an FG sensor and a waveform shaping circuit for obtaining N pulse signals (N.gtoreq.1 where N is an integer) in one rotation of a motor so as to control the rotation speed of the motor in accordance with period information of the FG pulse signal outputted from the waveform shaping circuit. The motor speed control device is further provided with an FG nonuniformity correcting circuit for correcting, by using respective period information of a rising edge-falling edge period and a falling edge-rising edge period, periodic nonuniformity of each period. The motor speed control device controls the motor in response to an actual speed error signal whose nonuniformity such as a duty error and a phase error has been corrected by the FG nonuniformity correcting circuit.

Abstract: A power tool has a variable speed control circuit that comprises a user switch, a motor and a silicon controlled rectifier (SCR) connected in series between a pair of power supply terminals. A manually variable resistor is connected between a first electrode of the SCR and a circuit node. A capacitor is coupled between the circuit node and a second SCR electrode. A bleed-off resistor is connected between second electrode of the SCR and the circuit node to provide a path for discharging the capacitor when the user switch is open. A zener diode couples the circuit node to the SCR gate electrode. The circuit configuration ensures that the capacitor charges from substantially the same voltage level at the start of each half-cycle during which the SCR is to be turned on.

Abstract: An electric oscillating tool, having particular but not necessarily exclusive utility as an electric toothbrush, for driving a brush head assembly or end effector with a resonant mechanism at high frequencies. The electric toothbrush includes handle housing, an electromagnetic motor mounted in the housing, and a mechanical oscillator acted upon by the motor. One end of the mechanical oscillator extends outwardly through an opening in the handle housing while the other end is attached to the housing inside the chamber. The end effector/brush head assembly attaches to the extending end of the mechanical oscillator. A power source supplies an alternating current drive signal to the motor, in turn causing the armature and the mechanical oscillator to oscillate and drive the brush head assembly.

Abstract: A frequency to be monitored is taken to a counter for the continuous measurement of its cycle time. The counter is so set that, when this frequency drops, i.e. when its cycle time increases, it reaches a certain condition and issues error signals (flags) as long as the condition lasts. The first flag actuates a flip-flop which in turn actuates a timer (alarm counter) which, after a short time, triggers an alarm unless it has previously been stopped by the resetting of the flip-flop. The flags are also continuously sent to a second counter which is so arranged that it cannot reach a certain (high) condition in the interval between two successive flags for a continued condition of the first counter. If the frequency to be monitored becomes normal again, the flags disappear and the last flag occurring once again starts this second counter so that it rises to the preset (high) position and emits a reset signal.

Abstract: A power tool has a variable speed control circuit that comprises a user switch, a motor and a thyristor connected in series between a pair of power supply terminals. A manually variable resistor is connected between a first electrode of the thyristor and a circuit node. A capacitor is coupled between the circuit node and the second thyristor electrode. A bleed-off resistor is connected between second thyristor electrode and the circuit node to provide a path for discharging the capacitor when the user switch is open. A semiconductor trigger device, such as a diac or silicon trigger switch, couples the circuit node to the thyristor gate electrode. The circuit operation ensures that the capacitor charges from substantially the same voltage level at the start of each half-cycle during which the thyristor is to be turned on.

Abstract: A frequency to be monitored is taken to a counter for the continuous measurement of its cycle time. The counter is so set that, when this frequency drops, i.e. when its cycle time increases, it reaches a certain condition and issues error signals (flags) as long as the condition lasts. The first flag actuates a flip-flop which in turn actuates a timer (alarm counter) which, after a short time, triggers an alarm unless it has previously been stopped by the resetting of the flip-flop. The flags are also continuously sent to a second counter which is so arranged that it cannot reach a certain (high) condition in the interval between two successive flags for a continued condition of the first counter. If the frequency to be monitored becomes normal again, the flags disappear and the last flag occurring once again starts this second counter so that it rises to the preset (high) position and emits a reset signal.

Abstract: A motor control apparatus controls a motor speed according to a detected period of a frequency signal whose frequency is in proportion to the motor speed and drives the motor so as to keep its speed fixed according to a drive signal. The motor control apparatus includes a disturbance torque observer receptive to the drive signal and the detected period which produces a estimated disturbance signal corresponding to a conversion of a disturbance torque into an electrical signal. A comparator produces a period error signal which is a difference between the detected period and a desired period. An arithmetic unit produces the control signal in accordance with the period error signM. A torque correcting unit produces the drive signal by adding the estimated disturbance signal to the control signal.

Abstract: A system for controlling the start-up sequence of an electric motor includes a contactor relay for supplying polyphase operating voltage to the motor. A plurality of output circuits are respectively coupled between the motor and the relay contacts. Each output circuit is responsive to an output control signal applied to an input thereof for applying the operating voltage to the motor. An acceleration ramp generator is responsive to a motor control circuit which energizes the relay for providing a first signal which gradually rises upon the initial activation thereof. A phase control ramp generator is responsive to the application of the polyphase operating voltage to provide a second signal which decreases from a given level upon the initial application of the operating voltage. A plurality of comparators are provided each comparator having first and second inputs respectively coupled to receive each phase control ramp generator signal and the acceleration ramp generator signal.

Abstract: An output circuit having a fail-safe function with: a control signal generating circuit which generates a control signal to control the current of a load and includes an operational amplifier which amplifies a difference between a control value and a feedback value to produce the control signal; a drive circuit which drives a load according to the control signal from the operational amplifier; an output current detecting circuit for detecting a current in a load solenoid and adding an offset current to the detected current, with the output of the output current detecting circuit being fed back to the control voltage generating circuit as the feedback value.

Abstract: An electromagnetic servo device (200) includes a driving control circuit (100), for an electric motor (20) for producing auxiliary torque to be applied to an output shaft (4). A control signal (Va) is provided to thereby supply an armature current (Io) of a controlled quantity, in a controlled direction of conduction thereof, in accordance with a detection signal (Vr, Vl) from a detection mechanism (13). The detection mechanism detects a phase difference (dP) between an input shaft (1) and the output shaft (4). The rotation speed (N) of the electric motor (20) is controlled with the control signal (Va), and is proportional to the quantity of the phase difference (dP).