A micro fan is provided. The micro fan includes a rotor and a stator. The stator includes a plurality of axial induced coil units and a circuit board. The axial induced coil units are respectively preformed as a plurality of stator magnetic pole units, and are coupled to the circuit board. At least one of the coil units includes a coil and insulation material. The insulation material is block-shaped and covers at least a portion of the coil, and the central axis of the coil is parallel to the shaft of the rotor.

A micro fan is provided. The micro fan includes a rotor and a stator. The stator includes a plurality of axial induced coil units and a circuit board. The axial induced coil units are respectively preformed as a plurality of stator magnetic pole units, and are coupled to the circuit board. At least one of the coil units includes a coil and insulation material. The insulation material is block-shaped and covers at least a portion of the coil, and the central axis of the coil is parallel to the shaft of the rotor.

A brushless motor is provided that includes a stator assy and a rotor. The stator assy includes a stator, a housing that has a space where the stator is disposed, and an insulating resin disposed in the space. The insulating resin fixes the housing to the stator. The housing includes a first housing member and a second housing member. The insulating resin also fixes first housing member to the second housing member.

A brushless motor is provided that includes a stator assy and a rotor. The stator assy includes a stator, a housing that has a space where the stator is disposed, and an insulating resin disposed in the space. The insulating resin fixes the housing to the stator. The housing includes a first housing member and a second housing member. The insulating resin also fixes first housing member to the second housing member.

A shaft of a motor includes a first shaft and a second shaft extending from the first shaft to one axial side. A housing includes a neutralizing device holder that holds a first neutralizing device. The neutralizing device holder includes a seal holder that is arranged radially outward of the second shaft and holds a seal member. The first neutralizing device electrically connects the second shaft and the neutralizing device holder. The seal member seals a gap between the second shaft and the seal holder, and is arranged on the other axial side of the first neutralizing device.

A shaft of a motor includes a first shaft and a second shaft extending from the first shaft to one axial side. A housing includes a neutralizing device holder that holds a first neutralizing device. The neutralizing device holder includes a seal holder that is arranged radially outward of the second shaft and holds a seal member. The first neutralizing device electrically connects the second shaft and the neutralizing device holder. The seal member seals a gap between the second shaft and the seal holder, and is arranged on the other axial side of the first neutralizing device.

A discharge device for discharging electric currents in a machine from a rotor part to a stator part, the rotor part in particular having a shaft, the discharge device comprising a contact element and a spring being connectable to the stator part in an electrically conductive manner, the contact element made predominantly of carbon, the contact element pressurized with a contact force by the spring for realizing an electrically conductive sliding contact between a sliding contact surface of the contact element and an axial shaft contact surface of the shaft. The contact element is circular, the sliding contact surface being at least annular in shape and disposed coaxially in relation to the shaft contact surface, the spring includes a circular support section which at least in part coaxially envelops the shaft of the machine, the support section being configured for radially abutting against an abutment surface of the stator part.

A discharge device for discharging electric currents in a machine from a rotor part to a stator part, the rotor part in particular having a shaft, the discharge device comprising a contact element and a spring being connectable to the stator part in an electrically conductive manner, the contact element made predominantly of carbon, the contact element pressurized with a contact force by the spring for realizing an electrically conductive sliding contact between a sliding contact surface of the contact element and an axial shaft contact surface of the shaft. The contact element is circular, the sliding contact surface being at least annular in shape and disposed coaxially in relation to the shaft contact surface, the spring includes a circular support section which at least in part coaxially envelops the shaft of the machine, the support section being configured for radially abutting against an abutment surface of the stator part.

A method for driving a single-phase electric motor includes switching drive electronics to a first on-state during a first on-time interval of a pulse width modulation period, switching the drive electronics to a second on-state during a second on-time interval of the pulse width modulation period, switching the drive electronics to an off-state between the first and second on-time intervals, and measuring the phase current with a current sensor. The first and the second on-time interval of one pulse width modulation period are provided with different interval lengths if a defined effective duty cycle is lower than a first duty cycle threshold value so that one of the first and the second on-time interval has an interval length which is equal to or larger than a defined minimum on-time interval length. The phase current is measured during the first and/or second on-time interval with the defined minimum on-time interval length.

A method for driving a single-phase electric motor includes switching drive electronics to a first on-state during a first on-time interval of a pulse width modulation period, switching the drive electronics to a second on-state during a second on-time interval of the pulse width modulation period, switching the drive electronics to an off-state between the first and second on-time intervals, and measuring the phase current with a current sensor. The first and the second on-time interval of one pulse width modulation period are provided with different interval lengths if a defined effective duty cycle is lower than a first duty cycle threshold value so that one of the first and the second on-time interval has an interval length which is equal to or larger than a defined minimum on-time interval length. The phase current is measured during the first and/or second on-time interval with the defined minimum on-time interval length.