Abstract: There is provided a spindle motor including a stator including a base member in which a stator core is fixedly installed, and a rotor including a rotor hub in which a driving magnet disposed to face the stator core is installed, wherein the driving magnet is installed on a magnet mounting part provided in the rotor hub so that the magnetic center thereof in an axial direction is disposed in a position higher than that of the magnetic center of the stator core in the axial direction in order to generate force directed in a downward axial direction by interaction with the stator core, and the stator core is formed of a soft magnetic material and includes protrusion parts formed at a front end portion thereof disposed to face the driving magnet and extended therefrom in the axial direction.

Abstract: A spindle motor includes a stator including a base member having a stator core installed thereon; and a rotor including a rotor hub in which a driving magnet facing the stator core is installed. The rotor hub includes a disk-shaped body, a magnet mounting part extended from edge of the body in a downward axial direction and having the driving magnet installed on an inner surface thereof, and a disk support part extended from the magnet mounting part in radial direction. A magnetic center of the driving magnet is higher than that of the stator core in the axial direction in order to generate force directed in the downward axial direction through interaction with the stator core. The magnet mounting part includes a vortex generation suppressing part disposed on a lower edge portion thereof to decrease noise and vibrations generated by flow of air during rotation of the rotor hub.

Abstract: There is provided a spindle motor for a 2.5? type disk driving device, including: a base having a stator core seating part protruding upwardly in an axial direction; a stator core including a ring-shaped coreback part, a tooth part, and a front end part; and a coil wound around the stator core, wherein when a length of the stator core from an inner end portion of the coreback part to the endmost part of the front end part is defined as L and a height of the wound coil from the lowermost edge of the coil in an axial direction to the uppermost edge thereof is defined as H, a ratio (H/L) of the height of the wound coil to the length of the stator core in which back electromotive force (B-EMF) is 0.35 V/Krpm or more when the supply of power is stopped satisfies 0.524?H/L?0.703.

Abstract: There is provided a spindle motor for a 2.5? type disk driving device, including: a base having a stator core seating part protruding upwardly in an axial direction; a stator core including a ring-shaped coreback part, a tooth part, and a front end part; and a coil wound around the stator core, wherein when a length of the stator core from an inner end portion of the coreback part to the endmost part of the front end part is defined as L and a height of the wound coil from the lowermost edge of the coil in an axial direction to the uppermost edge thereof is defined as H, a ratio (H/L) of the height of the wound coil to the length of the stator core in which back electromotive force (B-EMF) is 0.35 V/Krpm or more when the supply of power is stopped satisfies 0.524?H/L?0.703.

Abstract: Disclosed herein is an air duct assembly for vehicles which reduces noise generated by the flow of intake air which flows along a path of the air duct provided in a vehicle and is fed to an engine. The air duct reduces the noise of a low frequency range in initial engine start operation, and in addition, the noise of a whole frequency range, thus allowing a vehicle to be traveled while providing the environment having minimum noise to a driver and passenger riding in the vehicle. Therefore, it is not necessary to install an additional resonator.

Abstract: Disclosed herein is an air duct assembly for vehicles which reduces noise generated by the flow of intake air which flows along a path of the air duct provided in a vehicle and is fed to an engine. The air duct reduces the noise of a low frequency range in initial engine start operation, and in addition, the noise of a whole frequency range, thus allowing a vehicle to be traveled while providing the environment having minimum noise to a driver and passenger riding in the vehicle. Therefore, it is not necessary to install an additional resonator.