According to a motor rotational angle detection device which includes a plurality of motor rotational angle detection units which detect a rotational angle of a motor, and a normal angle decision device which includes a motor rotational angle information item and decides a normal motor rotational angle, in which when a difference is caused between output values of the plurality of motor rotational angle detection units, the normal angle decision device respectively compares the output value of each of the motor rotational angle detection units with the motor rotational angle information item included in the normal angle decision device, and identifies the normal motor rotational angle detection unit, and decides the normal motor rotational angle.

A method is for calibrating a multiturn sensor for determining the position of a spindle of a clutch actuator, in which the multiturn sensor (5) is operatively connected to a magnetic field of a permanent magnet (12) in that the multiturn sensor (5) is combined with an actuator transmission (3) which comprises a spindle (9) bearing the permanent magnet (12). In a calibration method which can be carried out particularly quickly and cost-effectively, during the assembly of the multiturn sensor (5), arranged on a carrier element (4), with the actuator transmission (3) bearing the spindle (9), the multiturn sensor (5) is operated outside its specified rotational range (0, n), wherein a position, set by actuating the actuator transmission (3), of the spindle (9) bearing the permanent magnet (12) provided for an operating case of the clutch actuator (1), is assigned to a specified end position of the rotational range (0, n) of the multiturn sensor (5), as a result of which a magnetic field of the permanent magnet (12) is aligned with the multiturn sensor (5).

A method is for calibrating a multiturn sensor for determining the position of a spindle of a clutch actuator, in which the multiturn sensor (5) is operatively connected to a magnetic field of a permanent magnet (12) in that the multiturn sensor (5) is combined with an actuator transmission (3) which comprises a spindle (9) bearing the permanent magnet (12). In a calibration method which can be carried out particularly quickly and cost-effectively, during the assembly of the multiturn sensor (5), arranged on a carrier element (4), with the actuator transmission (3) bearing the spindle (9), the multiturn sensor (5) is operated outside its specified rotational range (0, n), wherein a position, set by actuating the actuator transmission (3), of the spindle (9) bearing the permanent magnet (12) provided for an operating case of the clutch actuator (1), is assigned to a specified end position of the rotational range (0, n) of the multiturn sensor (5), as a result of which a magnetic field of the permanent magnet (12) is aligned with the multiturn sensor (5).

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.

The present invention may provide a motor including a rotary shaft, a yoke coupled to the rotary shaft, a stator disposed between the rotary shaft and the yoke, a first magnet and a second magnet disposed in the yoke, and a circuit board on which a first Hall sensor is disposed to correspond to the first magnet and a second Hall sensor is disposed to correspond to the second magnet, wherein the second magnet includes a plurality of split magnets and one index magnet, a width of the split magnet in a circumferential direction is the same as a width of the index magnet in the circumferential direction, each of the split magnets and the index magnet are formed by combining a first pole and a second pole, a width of the first pole of the split magnet in the circumferential direction is the same as a width of the second pole in the circumferential direction, and a width of the first pole of the index magnet in the circumferential direction is different from a width of the second pole in the circumferential direction.

The present invention may provide a motor including a rotary shaft, a yoke coupled to the rotary shaft, a stator disposed between the rotary shaft and the yoke, a first magnet and a second magnet disposed in the yoke, and a circuit board on which a first Hall sensor is disposed to correspond to the first magnet and a second Hall sensor is disposed to correspond to the second magnet, wherein the second magnet includes a plurality of split magnets and one index magnet, a width of the split magnet in a circumferential direction is the same as a width of the index magnet in the circumferential direction, each of the split magnets and the index magnet are formed by combining a first pole and a second pole, a width of the first pole of the split magnet in the circumferential direction is the same as a width of the second pole in the circumferential direction, and a width of the first pole of the index magnet in the circumferential direction is different from a width of the second pole in the circumferential direction.

Provided is an electric driving device including a plate member which is made of a material having electroconductivity, and is arranged between a cover and a control unit main body. An electroconductive member made of a material having electroconductivity is provided to the cover. The plate member includes a first mounting portion and a second mounting portion. The first mounting portion is mounted to a control unit main body, and a second mounting portion is formed at a position different from a position of the first mounting portion. The electroconductive member has a connection portion which projects from the cover. At least one of the second mounting portion or the connection portion is more deformable than the plate member except for the second mounting portion.

The present invention relates to a DC motor that is used in overall industrial fields producing electric cars, cordless vacuum cleaners, drones, and the like, and the existing high-efficiency DC motor, in which top and bottom permanent magnets have different polarities are arranged in a state where their centers alignedly face each other and electromagnets are disposed between the top and bottom permanent magnets to utilize magnetic forces to the maximum and to produce a rotation force thereof, is suggested. However, the existing high-efficiency DC motor has the following problems. Firstly, the rotation direction is not constant according to the initial position of the rotor, and secondly, the top and bottom permanent magnets attract the magnetic materials of the electromagnets to inhibit the rotation, and to solve such problems, accordingly, a high-efficiency DC motor according to the present invention is configured to allow centers of bottom permanent magnets to be facingly disposed between top permanent magnets, thereby exhibiting excellent rotation force and torque when compared to a general BLDC motor.

A power tool includes a motor (8) having a stator (9), a rotor (10) and three terminals (81). The stator includes a tubular stator core (60) having six teeth (63), first and second electrically insulating members (61, 62) affixed to the stator core, and six coils (64) wound around the teeth such that three phases are defined. The three terminals are held by the first electrically insulating member and are respectively electrically connected to the three phases. All of the six coils may be formed by winding a single continuous winding wire (101) sequentially around each of the six teeth. All of the three terminals (81) may be disposed within a semicircular area of the stator core. At least a first crossover wire portion (102) of the winding wire may be disposed on the second electrically insulating member.