초록 ▼

An electric motor of the brushless type is disclosed which is so constructed and arranged as to provide a low braking torque. An electric power steering system incorporating such a motor is also disclosed. In a preferred arrangement, the motor comprises an interior permanent magnet motor. An advanta

An electric motor of the brushless type is disclosed which is so constructed and arranged as to provide a low braking torque. An electric power steering system incorporating such a motor is also disclosed. In a preferred arrangement, the motor comprises an interior permanent magnet motor. An advantage of providing a motor which generates low levels of braking torque in the event of a fault is that a driver can easily turn the wheel of the vehicle in the fault condition against the motor. This reduces the requirements for motor fault protection.

대표청구항 ▼

1. An electric power assisted steering system comprising a steering shaft, means defining a motor drive signal, and a motor adapted to apply an assistance torque to said shaft in response to said motor drive signal, wherein said motor comprises an interior permanent magnet motor having a rotor struc

1. An electric power assisted steering system comprising a steering shaft, means defining a motor drive signal, and a motor adapted to apply an assistance torque to said shaft in response to said motor drive signal, wherein said motor comprises an interior permanent magnet motor having a rotor structure, a stator, and a plurality of permanent magnets buried within said rotor structure flush with or below the surface of the rotor structure and a plurality of phase windings provided on said stator arranged concentrically with the rotor structure.