A power tool which contains a casing, a brushless motor (22) mounted inside the casing, a user actuated switch (38) mounted on the casing, and a circuit board (32) mounted inside the casing. The brushless motor (22) is adapted to drive one or more movable parts in the power tool. The circuit board (32) is mechanically connected to the brushless motor (22) and the switch (38) at the same time. As only a single, integrated circuit board (32) is configured in the power tool, the manufacturing cost is reduced and greater reliance and electrical safety can be achieved.

An electric machine having a housing with a stator chamber, an axle supported by at least one bearing assembly so that the axle may rotate with respect to the housing, a stator assembly with a stator core and a plurality of wire windings around the stator core, a rotor assembly with a magnet assembly for generating a magnetic field in the stator assembly wherein a coolant is circulated through the stator chamber over the stator core and plurality of wire windings to remove heat, and a plurality of thermoelectric devices. The thermoelectric devices are located around the inner circumference of the housing so that the coolant is circulated over the plurality of thermoelectric devices. The plurality of thermoelectric use the Peltier effect to cool the coolant flowing through the stator chamber or generate an electrical current that can be used by the electric machine.

An) electric machine with variable torque generation having a tunable Halbach array configuration. The electric machine includes a magnet assembly for generating a magnetic field. The magnet assembly includes a plurality of fixed magnets disposed in a ring arrangement so that fixed magnets having a north pole faced toward the rotor or stator are alternated with fixed magnets having a south pole faced toward the rotor or stator, a plurality of rotatable magnets disposed within a respective slot formed between two adjacent fixed magnets, a drive assembly for turning the rotatable magnets within the slots to vary the magnetic field generated by the magnet assembly in the rotor or stator, the drive assembly configured to turn the rotatable magnets between a first position wherein the magnetic field in the rotor or stator is augmented and a second position wherein the magnetic field in the rotor or stator is cancelled.

A cascade MosFet circuit design for variable gear switching using pulse width modulation (PWM) between electronic gears to achieve a smooth transition is disclosed. In an embodiment, in the system, there can be three separate stages of two or more switches from very low amperage to hundreds of amps that can be automatically selected within a chosen stage. The automatic switching can be programmed to be power (e.g., current) sensitive or can be both power and electronic gear sensitive as to cascade into the right MosFet combination for different gear settings and still select greater values for varying power levels. Such a smooth transition can allow the generator or motor using such cascade MosFet circuit design to operate more efficiently and/or more quietly.

A cascade MosFet circuit design for variable gear switching using pulse width modulation (PWM) between electronic gears to achieve a smooth transition is disclosed. In an embodiment, in the system, there can be three separate stages of two or more switches from very low amperage to hundreds of amps that can be automatically selected within a chosen stage. The automatic switching can be programmed to be power (e.g., current) sensitive or can be both power and electronic gear sensitive as to cascade into the right MosFet combination for different gear settings and still select greater values for varying power levels. Such a smooth transition can allow the generator or motor using such cascade MosFet circuit design to operate more efficiently and/or more quietly.

A drum motor, comprises a drum tube having a cavity formed therein and a longitudinal axis, a shaft, which runs in the longitudinal axis and on which the drum tube is mounted by means of at least one rotary bearing, an electric synchronous drive unit arranged in the cavity of the drum tube, having a stator and a rotor, which are arranged in the longitudinal axis of the drum tube and wherein the rotor is connected to the drum tube and the stator is connected to the shaft, and a control unit for controlling the synchronous drive unit. The control unit of the drum motor has a frequency converter and is fastened directly to the shaft.

A drum motor, comprises a drum tube having a cavity formed therein and a longitudinal axis, a shaft, which runs in the longitudinal axis and on which the drum tube is mounted by means of at least one rotary bearing, an electric synchronous drive unit arranged in the cavity of the drum tube, having a stator and a rotor, which are arranged in the longitudinal axis of the drum tube and wherein the rotor is connected to the drum tube and the stator is connected to the shaft, and a control unit for controlling the synchronous drive unit. The control unit of the drum motor has a frequency converter and is fastened directly to the shaft.

A motor assembly includes a motor, a controller controlling at least one aspect of operation of the motor, and a control housing defining a control chamber. The controller is in part received within the control chamber. The controller includes a main electronics board and a modular connector assembly. The modular connector assembly includes a secondary electronics board and a connector at least in part supporting the secondary electronics board. The connector includes an inner connector portion and an outer connector portion. The connector extends through the control housing such that the inner connector portion is disposed inside the control chamber and the outer connector portion is disposed outside the control chamber. The outer connector portion defines a first access portal facilitating access to a first component of the secondary electronics board.

A motor assembly includes a motor, a controller controlling at least one aspect of operation of the motor, and a control housing defining a control chamber. The controller is in part received within the control chamber. The controller includes a main electronics board and a modular connector assembly. The modular connector assembly includes a secondary electronics board and a connector at least in part supporting the secondary electronics board. The connector includes an inner connector portion and an outer connector portion. The connector extends through the control housing such that the inner connector portion is disposed inside the control chamber and the outer connector portion is disposed outside the control chamber. The outer connector portion defines a first access portal facilitating access to a first component of the secondary electronics board.

A power tool with a motor which is rotatable in a forward direction and a reverse direction. A tool holder is driven by the motor. The power tool has a user operable trigger for operating the motor, a reversing switch for choosing the direction of rotation of the motor and a controller. The controller determines a direction of rotation of the motor based on a characteristic of the motor.