Abstract: A control circuit for a motor has a driving state and a braking state and includes a driving branch and a braking branch. The driving branch includes a branch formed by a stator winding and a rotor. The braking branch includes a branch formed by the stator winding, a braking switch, and an electrical energy storage component. The electrical energy storage component is configured to provide an electrical energy to the braking branch. When the motor is in the braking state, if the braking branch is detected as short-circuited, the connection between the stator winding and the rotor of the driving branch is turned on. Further provided is a power tool including the above control circuit.

Abstract: Multiplex winding synchronous power generating systems and vehicle power systems are provided that include a rotating part including a plurality of windings, a primer mover configured to drive the rotating part, a stator part having a plurality of windings, a plurality of rectifiers, three 3-phase 5-level motor drives, at least one H-bridge, at least one 3-phase AC motor, and a generator voltage regulator that regulates current of voltages of local DC busses of the three 3-phase 5-level motor drives.

Abstract: A multi-phase brushless direct-current motor and a drive method therefor. The motor comprises a motor body and a driving module, and the driving module comprises a controller, a plurality of H-bridge unipolar inverters each of which for a respective phase, and independent phase coil windings (1) which are successively electrically connected. The method comprises: outputting pulse width-modulated sine waves with identical frequency and amplitude from the controller thereby driving respective ones of the plurality of H-bridge unipolar inverters for each phase; wherein the pulse width-modulated sine waves correspond to every two adjacent phase coil windings having a non-zero phase difference, and phase differences of the plurality of phase coil windings are identical; and outputting sine wave driving voltages or sine wave driving currents in their corresponding phases from the respective ones of the plurality of H-bridge unipolar inverters to the corresponding, electrically connected phase coil windings.

Abstract: A high voltage, low current electric motor. The motor comprises a drive shaft turned by a sprocket that is driven by an assembly of electromagnets. A carrier supporting permanent magnets travels in a tubular track formed into an endless loop around the sprocket. The carrier preferably comprises a chain formed of interconnected links, each link housing a magnet. The tubular track is non-ferrous and forms a core for a plurality of coils spaced around the tube. A sequencing circuit in the motor sequentially energizes the coils to cause the carrier to circulate around the tube by repelling and attracting the magnets. Teeth on the sprocket engage the chain so that as the chain travels through the tube the sprocket is rotated. Preferably, the coils are double-wound so that a direction control circuit may be included to selectively reverse the direction of the carrier's travel. Speed control also may be included.

Abstract: An electrical rotating apparatus comprises an inverter system that outputs more than three phases. The apparatus further includes a stator electrically coupled to the inverter system, and a rotor electromagnetically coupled to a magnetic field generated by the stator. A signal generator generates a pulse modulated drive waveform signal, that has a frequency synchronized with the rotational frequency of the rotor, and the pulse modulated drive waveform signal drives the inverter system. The pulse modulated drive waveform signal has a pulsing frequency. Additionally, the inverter system may be fed by a pulse modulated drive waveform signal that is fed through at least one signal delay device. Alternatively, the system may also be fed selected harmonic components, such as the third harmonic, up until the number of phases in the apparatus.

Abstract: An electric motor for driving a component, such as a vehicle window lifter or a machine tool, functions as a generator, when the motor drive voltage is switched off and the motor is short circuited. The motor keeps running due to inertia or other influences. During this period after switch-off a generator voltage and respective generator current are produced. The generator current is measured for various purposes, preferably in combination with a measured r.p.m. signal. The generator current signal alone, or in combination with the r.p.m. signal, is evaluated to provide information regarding the motion of the driven component including information regarding the motion direction and position of the component.

Abstract: In order to brake a brushless motor in a forward rotation to give a reverse rotation force, source-side and sink-side transistors for supplying driving circuits *a, *b, *c, *d, *e, *f are periodically switched on and switched off based on the oscillation frequency of an oscillator (13) when a both end voltage of a current detection resistance (10) is higher than a reference voltage Vref. Moreover, the transistors are kept in an ON state all the time when the both end voltage of the current detection resistance (1) has lowered below the reference voltage Vref. With this arrangement, damage to a source-side transistor due to a large current flowing thereinto when the motor rotating in a reverse direction can be prevented.

Abstract: The present invention is an electronic lock having a shorting or shunt circuit designed to allow an authorized operator to open the electronic lock and which will prevent an unauthorized operator from opening the lock when authorized combination has not been entered.

Abstract: A motor drive system for selectively supplying a drive current to a multiple phase motor having each phase winding divided into a plurality of discrete windings includes a plurality of H-bridge drives to control the polarity and magnitude of the drive current. Each H-bridge drive include a pair of half bridge drives interconnected to the terminals of each of the discrete windings. Each of the half bridges have an upper bridge switching element and a lower bridge switching element for coupling the positive and negative potential, respectively, of a DC power source to each discrete winding. The discrete windings of each phase winding are coupled in series by a plurality relays which are selectively actuated by a controller to interconnect the discrete windings in predetermined groups dependent upon the shaft speed of the motor.

Abstract: A control circuit provides, for connecting a motor to a d.c. voltage source (1), two half bridge (3, 7, 5, 9) each with a respective switch (3, 5) with controlled opening and closing; the first of the half bridge connects a pole of the excitation winding (13) to the source (1) and the second of the half bridge connects a pole of the armature (15) to the source (1). A control unit (11) controls the opening and closing of the two switches (3, 5) of the half bridge and the toggling of the reversing device as a function of the operating conditions of the motor. The control unit (11) is programmed in such a way that in the braking phase it toggles both of the controlled switches (3, 5) cyclically, simultaneously or independently, from an open condition to a closed condition and vice versa.

Abstract: A circuit for driving a voice coil motor used to position the heads of a disk drive is disclosed. The circuit consists of a an H-bridge circuit, a controller, and a feedback loop. The feedback loop prevents the BEMF from driving a voltage on the voice coil motor above the supply voltage.

Abstract: An artificial heart assembly, designed for implantation into a subject, which may be a total artificial heart or a ventricular assist device. The artificial heart assembly has a blood inlet conduit, a blood outlet conduit, a pumping mechanism for pumping blood from the blood inlet conduit to the blood outlet conduit, and a sensorless, DC brushless motor operatively connected to the pumping mechanism. The motor is reversibly driven in a first direction and a second direction, the motor changing between the first and second directions at a rate of at least 30 times per minute. The artificial heart assembly has means for periodically applying electrical signals to a plurality of the motor terminals while leaving at least one of the motor terminals unenergized, means for detecting a voltage at the unenergized motor terminal, and means for determining, based upon the voltage at the unenergized terminal, the angular position of the rotor with respect to the stator.

Abstract: A permanent magnet rotor is connected to an output shaft and has more than one pair of magnetic poles. A stator has three phases connected in Y-connection including a first phase, a second phase, and a third phase. Each phase has as many series-connected coils as there are pairs of the poles of the magnet rotor. A timer circuit outputs a first signal for a predetermined length of time when a target angular position of said rotor is selected. On the basis of a present angular position of the rotor and the target angular position of the rotor, a rotation direction commanding circuit outputs a second signal indicative of the rotation direction of rotor. In accordance with the signal, a current polarity control circuit supplies a first current to the first phase (subcoils) in accordance with the first signal and a second current to the second and third phases (main coils) in accordance with the second signal so as to drive the rotor into rotation to the target angular position.

Abstract: Control apparatus having two-fault tolerance for two position, motor operated actuators includes electronic circuitry for disconnection of the power return to the actuator motor armature thereby insuring that the motor will not be activated upon an inadvertent connection of power to either motor power input, and for indication of disconnection thereto. Testing determines the operatonal status of a motor relay and also determines inadvertent applications of power to the one of the pair of motor power inputs that is not connected to the power source through the position switch and one of the pair of limit switches. A relay and motor indication are operable to indicate either motor operation or inadvertent power interruptions in the one of the pair of motor power inputs most recently connected to the power source through the position switch and one of the pair of limit switches.

Abstract: A reversible linear motor has a coil arrangement arranged alongside a conductive body such as a rotatable aluminium disc. The coil arrangement is made up of three separate coils: namely an inner coil and two interconnected outer coils on opposite sides of the inner coil. The coils are connected to a single phase a.c. supply and the drive of the disc can be reversed by reversing the connection of the inner coil relative to the two outer coils. The linear motor may be used for driving a reel of an entertainment machine of the fruit machine kind.

Abstract: A circuit for controlling the drive direction of an electrically-driven vehicle, the circuit having a plurality of spring return input switches (20) each actuation of which changes the direction of the vehicle, via a flip-flop circuit (21), an amplifier (22), and a relay (13); the direction contactor coils (10, 11) of the vehicle being connected in alternative circuits through the contacts of the relay (13).

Abstract: In a D.C. motor in which signals generated by an angular position transmitter control the commutation of the current flowing through the stator winding via a selection circuit containing Exclusive OR gates by means of which the polarity of the signals generated by the angular position transmitters can be reversed for the reversal of the direction of rotation, operating modes of "Operation" and "Braking" can be specified with only one command input for the Exclusive OR gates using an additional Exclusive OR gate.

Abstract: A brushless DC motor capable of change of rotational direction is disclosed. The feed of a high-frequency voltage signal to switching elements is sequentially changed to orderly excite stator windings by the outputs from rotor angular position detectors so that the rotor is rotated in a desired direction. Another high-frequency voltage signal is applied to the switching elements at a time when opposite direction rotation is required, so that the high-frequency voltage signal applied to one of the switching elements in response to the outputs of the detectors is cancelled by the other high-frequency voltage signal. Therefore, the order of the excitation of stator windings is inverted and, thus, the rotor is rotated in the opposite direction.The other high-frequency voltage signal has the same frequency as, a greater amplitude than, and a phase difference of 90.degree.-270.degree.

Abstract: An electronic reversible motor operated valve assembly adapted to be controlled by a two-wire thermostat. The assembly includes a valve casing having a pivotally mounted valve member, and a reversible motor drive unit having forward and reverse motor windings which, when alternately energized, effect pivoting of the valve member between closed and open positions to control fluid flow through the valve casing. The assembly includes a triac having a first annode and a gate coupled across the two wires of the thermostat, and having a second annode and the gate coupled across separate end terminals of the motor windings. Commonly connected end terminals of the motor windings and the first annode of the triac are coupled to an A/C power source to afford biasing the triac. When the thermostat switches to an off state, the triac is biased on and the reverse motor winding is energized to pivot the valve to the open position.

Abstract: A driving system for reversibly rotating a D.C. brushless motor is disclosed. The system comprises Hall generators for detecting positions of a rotor, and a drive circuit for controlling conduction and interruption of current applied to stator windings making use of output of said Hall generators. The system further comprises an inversion control circuit including a switch for reversibly switching polarities of an applied power source in order to reversibly rotate the D.C. motor thereby reversibly inverting the D.C. motor in response to signals from the power source whose polarities vary alternately.