A motor driving device having a lock protection mode includes a rotation speed detecting unit, an operating unit, a driving unit, a floating point selecting unit, a BEMF detecting unit, a control unit, and a lock protection unit. The operating unit enters an operating mode after a motor is stably operated, and generates an operating signal having phases according to a commutation sequence, and the driving unit drives the motor. The BEMF detecting unit detects a BEMF of a first floating phase to generate a detection result. The control unit outputs a commutation signal to cause the driving unit to drive the motor. When the rotation speed detecting unit determines that a rotation speed of the motor exceeds a predetermined rotation speed, the rotation speed detecting unit outputs a switching signal to the lock protection unit to enter the lock protection mode.

A shift range switching system includes: a motor that includes a motor winding and generates a cogging torque by a permanent magnet; a drive circuit; an output shaft; a shift range switching mechanism that includes a trough providing member with troughs and crests and integrally rotates with the output shaft, an engagement member that fits in one trough corresponding to a shift range, and an urging member that urges the engagement member toward the one trough; and a control unit. The engagement member drops into the one trough with an allowance. When an abnormality occurs in a motor drive system in an ascending action in which the engagement member moves from one trough toward one crest, the shift range switching system reduces an occurrence probability of an intermediate range stop abnormality.

In a method for generating a blocking moment in a standstill state of an electrically commutated electric motor having at least two windings, on which electric motor a possibly varying load moment acts from outside in the standstill state, first, a blocking current is supplied at a maximum value into a first winding. This blocking current is successively reduced to, possibly, a minimum value. From that moment the inductivity of the electric motor is controlled, namely by controlling the blocking current if the control deviation between the actual value and the set value of the inductivity exceeds a predetermined threshold value. Thereby, it is possible to control the blocking current in an adaptive manner insofar as, despite a varying load moment, the standstill state of the electric motor can be maintained by varying the blocking current.

A control device of an electric motor that drives an axis influenced by gravity includes: a determination unit that determines whether an overrun operation to move past a target position of the axis is allowable; and a drive control unit that, in a case in which it is determined by the determination unit that the overrun operation is allowable and the axis is driven in an antigravity direction, controls driving of the electric motor so that, after the axis being driven to the overrun position past the target position in the antigravity direction, the axis is driven again in a gravity direction to stop at the target position.

An electric actuator includes a casing having a base, on which an electric motor is fixed having a stator with radially extending straight teeth and having a plurality of coils and a rotor formed by a plurality of magnets. The coils extend in a plane parallel to the base of the casing and the rotor is extended by a pinion forming a worm gear with an axis perpendicular to the orientation of the coils. The worm gear meshes with a threaded rod extending parallel to the base of the casing, wherein the threaded rod is guided at the rear by a fixed smooth bearing or by a fixed nut, with the smooth bearing or nut being rigidly connected to a cover of the casing. The axial end of the worm gear is guided by the cover and a printed circuit, to which the plurality of coils is connected, is positioned between the stator and the threaded rod.

A fire suppression system includes a motor and a foam pump. The foam pump is driven by the motor to inject one or more chemical additives from an off-board additive container into a discharge conduit. A bypass valve is in fluid communication with the output of the foam pump. One or more sensors are configured to measure at least one operating condition of the foam pump. A controller is in communication with the one or more sensors and is operatively connected to the bypass valve. The controller is configured to determine, based on data received from the one or more sensors regarding the at least one operating condition of the foam pump, whether the foam pump is experiencing a loss of prime, and to open the bypass valve in response. The motor may also selectively operate in one of two modes depending on the rotational speed and torque required.

A homing mechanism within a drive mechanism of a lacing engine for an automated footwear platform can include an indexing wheel, a plurality of Geneva teeth and a stop tooth. The plurality of Geneva teeth can be distributed around a portion of a perimeter of the indexing wheel. Each Geneva tooth of the plurality of Geneva teeth can include side profiles conforming to a first side profile that generates a first force when engaged by an index tooth on a portion of the drive mechanism. The stop tooth can be located along the perimeter of the indexing wheel between two Geneva teeth. Additionally, the stop tooth can include side profiles conforming to a second side profile that generates a second force when engaged by the index tooth.

A motor driving device having a lock protection mode includes a rotation speed detecting unit, an operating unit, a driving unit, a floating point selecting unit, a BEMF detecting unit, a control unit, and a lock protection unit. The operating unit enters an operating mode after a motor is stably operated, and generates an operating signal having phases according to a commutation sequence, and the driving unit drives the motor. The BEMF detecting unit detects a BEMF of a first floating phase to generate a detection result. The control unit outputs a commutation signal to cause the driving unit to drive the motor. When the rotation speed detecting unit determines that a rotation speed of the motor exceeds a predetermined rotation speed, the rotation speed detecting unit outputs a switching signal to the lock protection unit to enter the lock protection mode.

According to an aspect of the present disclosure, a motor drive control device driving a motor using position information detected by one sensor includes: a current detection unit detecting a magnitude of a coil current flowing through a coil of the motor; a rotation position detection unit detecting a rotation position of the motor based on the position information; and a hunting determination unit determining, based on the magnitude of the coil current, the rotation position of the motor, and a driving command for driving the motor, whether or not the motor is in a hunting condition.

An electric motor control device controls driving of electric motors connected in parallel with each other and includes a power converter converting power from a power supply, and supply the converted power to each of the electric motors, a switching device to be turned on to electrically connect the power converter and at least one of the electric motors and to be turned off to electrically disconnect the power converter and the at least one of the electric motors, a current detection unit detecting a current that flows in the electric motors, and a controller controlling the power converter on the basis of operation of the switching device, rotation frequency command values from an external device, and a value of the current detected by the current detection unit. The controller turns the switching device from off to on so that start timing of control is different for each electric motor.