Fan blower with durable bearing structure

A blower comprising:

• a frame including a base connected through stays to the frame so as to be positioned at a central portion of said frame,
• a cylindrical bearing holder formed integrally with said base to extend therefrom,
• a stator including an iron core and a coil and mounted on the exterior of the cylindrical bearing holder,
• an impeller including a first front face plate, a first flange formed over an outer periphery of the first front face plate, and a plurality of blades provided on an outer periphery of said first flange,
• a yoke including a second front face plate to which the first front face plate of the impeller is secured, a second flange formed over an outer periphery of the second front face plate, a magnet mounted on the second flange, and
• a bearing device to which the central portion of said yoke is fit and secured thereto, the bearing device including:
• a sleeve,
• a stepped shaft including a larger diameter portion and a reduced diameter portion provided at one end thereof,
• a first inner raceway groove formed around an outer peripheral surface of the larger diameter portion,
• a first outer raceway groove formed on an inner peripheral surface of the sleeve so ass to correspond with said first raceway groove,
• balls of a first row interposed between said first inner and outer raceway grooves,
• an inner ring slidably fit over the reduced diameter portion,
• a second inner raceway groove formed around an outer peripheral surface of the inner ring,
• a second outer raceway groove formed on an inner peripheral surface of the sleeve so as to correspond with said second inner raceway groove,
• balls of a second row interposed between the second inner and outer raceway grooves,
• a stop ring provided around an outer periphery of a distal end of the reduced diameter portion, and
• a pre-loading spring interposed between the stop ring and an end surface of the inner ring to provide a pre-loading force to the inner ring.

A blower comprising:

• a frame including a base connected through stays to said frame so as to be positioned at a central portion of said frame,
• a cylindrical bearing holder formed integrally with said base to extend therefrom,
• a stator including an iron core and a coil and mounted on the exterior of the cylindrical bearing holder,
• an impeller including a first front face plate, a first flange formed over outer periphery of said first front face plate, and a plurality of blades provided on an outer periphery of the first flange,
• a yoke including a second front face plate to which said first front face plate of said impeller is secured, a second flange formed over an outer periphery of the second front face plate, a magnet mounted on the second flange, and
• a bearing device for supporting a central portion of the yoke through a sleeve of said bearing device to which the central portion of the yoke is fit and secured thereto, said bearing device including:
• a sleeve,
• stepped shaft including a larger diameter portion and a reduced diameter portion provided at one end thereof,
• a first inner raceway groove formed around an outer peripheral surface of the larger diameter portion,
• a first outer raceway groove formed on an inner peripheral surface of the sleeve so as to correspond with the first inner raceway groove,
• balls of a first row interposed between the first inner and outer raceway grooves,
• an inner ring slidably fit over the reduced diameter portion,
• a second inner raceway grove formed around an outer peripheral surface of the inner ring,
• a second outer raceway groove formed on an inner peripheral surface of the sleeve so as to correspond with said second inner raceway groove,
• balls of a second row interposed between said second inner and outer raceway grooves,
• a stop ring provided around an outer periphery of a distal end of the reduced diameter portion, and
• a pre-loading spring interposed between the stop ring and an end surface of the inner ring to provide a pre-loading force to the inner ring.

A blower comprising:

• a frame including a base connected through stays to the frame so as to be positioned at a central portion of the frame,
• a cylindrical bearing holder formed integrally with said base to extend therefrom,
• a stator including an iron core and a coil and mounted on the exterior of the cylindrical bearing holder,
• an impeller including a first front plate, a first flange formed over an outer periphery of the first front face plate, and a plurality of blades provided on an outer periphery of the first flange,
• a yoke including a second front face plate to which the first front face plate of the impeller is secured, a second flange formed over an outer periphery of the second front face plate, a magnet mounted on the second flange, and
• a bearing device for supporting a central portion of the yoke through a sleeve thereof to which the central portion of the yoke is fit and secured thereto, the bearing device including:
• a sleeve,
• a steeped shaft including a larger diameter portion and a reduced diameter portion provided at one end thereof,
• a first inner raceway groove formed around an outer peripheral surface of the larger diameter portion,
• a first outer raceway groove formed on an inner peripheral surface of the sleeve so as to correspond with said first inner raceway groove,
• balls of a first row interposed between said first inner and outer raceway grooves,
• an inner ring slidably fit over the reduced diameter portion,
• a second inner raceway groove formed around an outer peripheral surface of the inner ring,
• a second outer raceway groove formed on an inner peripheral surface of said sleeve so as to correspond with said inner raceway groove,
• balls of a second row interposed between said second inner and outer raceway grooves,
• a stop ring provided around an outer periphery of a distal end of the reduced diameter portion, and
• a pre-loading spring interposed between the stop ring and an end surface of the inner ring to provide a pre-loading force to the inner ring, wherein
• the bearing device is provided within the cylindrical bearing holder so that the sleeve can be rotated around an axis of the bearing device, and an end of the shaft is secured to the base.

A blower comprising:

• a frame including a base connected through stays to the frame so as to be positioned at a central portion of the frame,
• a stator including an iron core and a coil and mounted on an inner peripheral surface of a first flange extending forwardly from an outer periphery of the base,
• an impeller including a front face plate, a second flange formed over an outer periphery of the front face plate, and a plurality of blades provided on an outer periphery of the second flange,
• a bearing device for supporting a central portion of a supporting plate mounted on a rear surface of said front face plate, the bearing device including:
• a sleeve to which the central portion of the supporting plate is fit and secured,
• a stepped shaft including a larger diameter portion and a reduced diameter portion provided at one end thereof,
• a first inner raceway groove formed around an outer peripheral surface of the larger diameter portion,
• a first outer raceway groove formed on an inner peripheral surface of the sleeve so as to correspond with said first inner raceway groove,
• balls of a first row interposed between said first inner and outer raceway grooves,
• an inner ring slidably fit over the reduced diameter portion,
• a second inner raceway groove formed around an outer peripheral surface of the inner ring,
• a second outer raceway groove formed on an inner peripheral surface of said sleeve so as to correspond with said second inner raceway groove,
• balls of a second row interposed between said second inner and outer raceway grooves,
• a stop ring provided around an outer periphery of a distal end of the reduced diameter portion, and
• a pre-loading spring interposed between said stop ring and an end surface of said inner ring to provide a pre-loading force to the inner ring,
• wherein an exterior of the sleeve of the bearing apparatus is provided with a cylindrical yoke on which is provided a magnet corresponding a magnet corresponding to said coil of said stator, and an end of said shaft is secured to the base.