A tool driver for use in robotic surgery includes a base configured to couple to a distal end of a robotic arm, and a tool carriage slidingly engaged with the base and configured to receive a surgical tool. In one variation, the tool carriage may include a plurality of linear axis drives configured to actuate one or more articulated movements of the surgical tool. In another variation, the tool carriage may include a plurality of rotary axis drives configured to actuate one or more articulated movements of the surgical tool. Various sensors, such as a capacitive load cell for measuring axial load, a position sensor for measuring linear position of the guide based on the rotational positions of gears in a gear transmission, and/or a capacitive torque sensor based on differential capacitance, may be included in the tool driver.

A drain cleaning machine includes a brushless direct current (DC) motor configured to rotate a snake about the snake axis. An electronic processor is configured to control power switching elements to drive the brushless DC motor. In a first operating range when a load experienced by the brushless DC motor is less than or equal to a predetermined load, the electronic processor is configured to control the power switching elements to drive the brushless DC motor at an approximately constant speed regardless of the load experienced by the brushless DC motor. In a second operating range when the load experienced by the brushless DC motor is greater than the predetermined load, the electronic processor is configured to control the power switching elements to drive the brushless DC motor at a decreasing speed as the load experienced by the brushless DC motor increases.

A drain cleaning machine includes a brushless direct current (DC) motor configured to rotate a snake about the snake axis. An electronic processor is configured to control power switching elements to drive the brushless DC motor. In a first operating range when a load experienced by the brushless DC motor is less than or equal to a predetermined load, the electronic processor is configured to control the power switching elements to drive the brushless DC motor at an approximately constant speed regardless of the load experienced by the brushless DC motor. In a second operating range when the load experienced by the brushless DC motor is greater than the predetermined load, the electronic processor is configured to control the power switching elements to drive the brushless DC motor at a decreasing speed as the load experienced by the brushless DC motor increases.

A rotary electric machine includes: a housing; a stator that is disposed in the housing; a rotating shaft that is rotatably disposed in the housing; a rotor that is disposed on the rotating shaft; and a rotational angle detecting apparatus that generates a signal that corresponds to a rotational angle of the rotating shaft. The rotational angle detecting apparatus includes: a magnetism generating body that is disposed on an axial end surface of the rotating shaft; and a magnetic sensor that faces the magnetism generating body. A recess portion is disposed on the end surface. The magnetism generating body is disposed in the recess portion.

A sensor system determines an absolute angular position of a to-be-sensed rotating member. The sensor system may include a rotor with a first magnet coupled to the rotor and a shaft having threads thereon. The sensor system may further include a sleeve with a second magnet and threads complementary to the threads of a shaft. The sleeve may be configured to travel axially along the shaft as a function of rotation of the rotor. The sensor system may also include a first transducer configured to sense orientation of the first magnet and at least one second transducer configured to sense a location of the second magnet along the shaft. Through use of the sensor system, an absolute number of turns and, consequently absolute angular position, of the rotating member can be determined.

Disclosed is an anti-separating structure of a sensing magnet for EPS motor, the structure being a coupling structure between the sensing magnet and a plate of the EPS motor, the structure including a disk-shaped plate formed with a magnet accommodation unit protrusively formed near at a rotation shaft, a ring-shaped sensing magnet centrally formed with a through hole having a diameter corresponding to the magnet accommodation unit, and magnet grip units each formed at a predetermined gap along a circumferential surface of the magnet accommodation unit.

Disclosed is an anti-separating structure of a sensing magnet for EPS motor, the structure being a coupling structure between the sensing magnet and a plate of the EPS motor, the structure including a disk-shaped plate formed with a magnet accommodation unit protrusively formed near at a rotation shaft, a ring-shaped sensing magnet centrally formed with a through hole having a diameter corresponding to the magnet accommodation unit, and magnet grip units each formed at a predetermined gap along a circumferential surface of the magnet accommodation unit.

Provided herein is a BLDC motor having a control system, a rotor including a motor magnet having a plurality of alternating magnetic poles thereon, a stator and a ring magnet. The ring magnet is mounted on the rotor axially adjacent the motor magnet. The number of poles on the ring magnet is an integer multiple of the number of poles on the motor magnet. Also provided is a method for controlling the BLDC motor including the steps of supplying a current to the motor, determining if the torque produced by the motor is in a positive or negative direction, determining a multiplier based on the direction of the torque, multiplying the supplied current by the multiplier, implementing a commutation sequence to provide current to the motor, measuring the current in each of the plurality of windings and adjusting the current provided to the motor based on the measured current.

Systems and methods of synchronously switching electrical phases of a permanent magnet synchronous motor are provided. Some embodiments can include switching the phase of the motor by employing an encoder that includes a tone wheel affixed to a rotor such that the tone wheel redirects a magnetic field away from Hall effect sensors in a timed manner.

The present invention provides a device and a method for changing over an electric machine from the regular operating mode into the open-circuit mode. In order to avoid excessive increases in voltage and associated adverse effects on the electric machine and the other components, in particular batteries, a further control phase is introduced between the end of the regular operating mode and the freewheeling mode, during which further control phase the voltage at the terminals of the electric machine is continuously adjusted from the voltage previously set in the regular operating mode to the expected open-circuit voltage of the electric machine.