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 identification method according to an embodiment is used for an identification device for identifying the type of a brushless DC motor. A brushless DC motor includes an output terminal for outputting a signal. The output terminal is able to output a signal obtained by superimposing signal types. The signal resulting from the superimposition is different depending on the types of brushless DC motors. In the identification method, power is supplied to a brushless DC motor, and the signal resulting from the superimposition that is output from the output terminal of the brushless DC motor is input to an identification device. The signal resulting from the superimposition is separated into signal types, and the separated signals are used to identify the type of the brushless DC motor.

The identification method according to an embodiment is used for an identification device for identifying the type of a brushless DC motor. A brushless DC motor includes an output terminal for outputting a signal. The output terminal is able to output a signal obtained by superimposing signal types. The signal resulting from the superimposition is different depending on the types of brushless DC motors. In the identification method, power is supplied to a brushless DC motor, and the signal resulting from the superimposition that is output from the output terminal of the brushless DC motor is input to an identification device. The signal resulting from the superimposition is separated into signal types, and the separated signals are used to identify the type of the brushless DC motor.

Disclosed is an electric motor with a stator, a rotor rotatably mounted relative to the stator and motor electronics. The motor electrics is arranged in an electronics housing and mounted on a circuit board. On the circuit board there is arranged at least one vibration sensor configured for measuring an acceleration and/or speed of vibrations of the electric motor in at least one direction. In addition, said circuit board is vibrationally coupled with other components of the electric motor using at least one coupling element, so that at least parts of the vibrations of the electric motor are transmitted to the vibration sensor. Furthermore, a fan is disclosed, including an electric motor and an impeller. A method for evaluating a vibration state of an electric motor is disclosed, wherein said electric motor can be formed by an electric motor as also disclosed herein.

Disclosed is an electric motor with a stator, a rotor rotatably mounted relative to the stator and motor electronics. The motor electrics is arranged in an electronics housing and mounted on a circuit board. On the circuit board there is arranged at least one vibration sensor configured for measuring an acceleration and/or speed of vibrations of the electric motor in at least one direction. In addition, said circuit board is vibrationally coupled with other components of the electric motor using at least one coupling element, so that at least parts of the vibrations of the electric motor are transmitted to the vibration sensor. Furthermore, a fan is disclosed, including an electric motor and an impeller. A method for evaluating a vibration state of an electric motor is disclosed, wherein said electric motor can be formed by an electric motor as also disclosed herein.

Methods and apparatus to control engine speed of a power system are disclosed. An example power system includes: an engine; a generator configured to generate electrical power from mechanical power delivered by the engine; a switched-mode power supply configured to convert the electrical power from the generator to output power; and control circuitry configured to: monitor an input current to the switched-mode power supply; and in response to the input current exceeding a threshold current, incrementally increasing a speed of the engine.

Methods and apparatus to control engine speed of a power system are disclosed. An example power system includes: an engine; a generator configured to generate electrical power from mechanical power delivered by the engine; a switched-mode power supply configured to convert the electrical power from the generator to output power; and control circuitry configured to: monitor an input current to the switched-mode power supply; and in response to the input current exceeding a threshold current, incrementally increasing a speed of the engine.

To provide a power tool configured to stably rotate an end tool. The provided power tool includes a brushless motor including a rotor configured to rotate; a rectifier circuit configured to rectify an AC voltage; a smoothing capacitor configured to smooth the AC voltage rectified by the rectifier circuit to a pulsating voltage; an inverter circuit configured to perform switching operations to output the pulsating voltage to the brushless motor; a deceleration mechanism including: a driving portion at a rotor side, a driven portion configured to transmit a rotating force to an end tool side, and an elastic member configured to transmit a rotational force of the driving portion to the driven portion, the deceleration mechanism configured to decelerate a speed of a rotation of the rotor and configured to transmit the rotation to an end tool.

The identification method according to an embodiment is used for an identification device for identifying the type of a brushless DC motor. A brushless DC motor includes an output terminal for outputting a signal. The output terminal is able to output a signal obtained by superimposing signal types. The signal resulting from the superimposition is different depending on the types of brushless DC motors. In the identification method, power is supplied to a brushless DC motor, and the signal resulting from the superimposition that is output from the output terminal of the brushless DC motor is input to an identification device. The signal resulting from the superimposition is separated into signal types, and the separated signals are used to identify the type of the brushless DC motor.

The identification method according to an embodiment is used for an identification device for identifying the type of a brushless DC motor. A brushless DC motor includes an output terminal for outputting a signal. The output terminal is able to output a signal obtained by superimposing signal types. The signal resulting from the superimposition is different depending on the types of brushless DC motors. In the identification method, power is supplied to a brushless DC motor, and the signal resulting from the superimposition that is output from the output terminal of the brushless DC motor is input to an identification device. The signal resulting from the superimposition is separated into signal types, and the separated signals are used to identify the type of the brushless DC motor.