Electric blower and electric cleaner using same

1. An electric blower, comprising:

a motor having a rotary shaft; and

an impeller rotationally driven by the motor, the impeller including:

a front shroud having a suction opening;

a rear shroud disposed with a space from the front shroud;

a plurality of sheet-metal blades fitted to and fixed between a pair of the front shroud and the rear shroud; and

a resin inducer disposed at a center portion of the impeller, the resin inducer including:

a cone-shaped hub part; and

a plurality of blade parts in a periphery of the hub part, the resin inducer rectifying suction-air flow taken from the suction opening, the resin inducer being divided into two parts in a plane perpendicular to the rotary shaft, the two parts being a first inducer and a second inducer, the first inducer including:

a ring-shaped first hub part forming the hub part and comprising a first fitting part; and

a plurality of first blade parts forming the blade parts, the first inducer being located upstream close to the suction opening in a passage of the suction-air flow,

the second inducer including:

 a cone-shaped second hub part forming the hub part and comprising a second fitting part engaging with the first fitting part; and

 a plurality of second blade parts forming the blade parts, the second inducer being located downstream farther away from the suction opening than the first inducer in the passage of the suction-air flow,

the second blade parts and the first blade parts each having a mating surface, the second blade parts and the first blade parts being mated and assembled to each other at the respective mating surfaces, the mating surfaces each having an engaging part for mating the second blade parts and the first blade parts,

the first hub part being disposed around an outer periphery of the second hub part,

the second inducer being secured to the rotary shaft by a fastener from a first hub part side,

the second blade parts and the first blade parts being guided to assemble by the first and the second fitting parts and coupled to each other at the engaging parts,

wherein

outer-peripheral blade-tips of the first blade parts are disposed in a proximity of the front shroud, an upper surface of the first hub part is disposed to be proximally covered by a lower surface of the fastener, and a height of the second hub part is one of equal to and larger than a height of the first hub part, with the first hub part disposed around the outer periphery of the second hub part,

whereby the first inducer is restricted from moving both in an axial direction of the rotary shaft and in a rotational direction of the rotary shaft.

2. The electric blower according to claim 1 , wherein the engaging parts include:

first steps disposed in the first blade parts; and

second steps engaging with the first steps, the second steps each disposed as a first projection in a negative pressure surface side of the second blade parts.

3. The electric blower according to claim 1 , wherein the engaging parts include:

third steps disposed in the first blade parts; and

fourth steps engaging with the third steps, the fourth steps each disposed as a first projection in a negative pressure surface side of the second blade parts, and include:

sixth steps disposed in the first blade parts; and

fifth steps engaging the sixth steps, the fifth steps being located in a pressure surface side of the second blade parts.

4. The electric blower according to claim 1 , wherein the engaging parts include:

seventh steps each having a third projection in a negative pressure surface side in an outer periphery side of the second blade parts; and

eighth steps engaging the seventh steps, the eighth steps being disposed in the first blade parts, and include:

ninth steps each having a fourth projection in a pressure surface side in an inner periphery side of the second blade parts; and

tenth steps engaging the ninth steps, the tenth steps being disposed in the first blade parts.

5. The electric blower according to claim 1 , wherein the mating surfaces of the engaging parts are mated to each other in a vertical plane, the mating surfaces being located in a direction along a circumference of the rotary shaft.

6. The electric blower according to claim 1 , wherein a height of the first and the second fitting parts is larger in an axial direction of the rotary shaft than that of the engaging parts.

7. The electric blower according to claim 1 , wherein

the second hub part is provided with a cylinder part,

the cylinder part is inserted on outer periphery of the rotary shaft,

the first hub part is inserted on outer periphery of the cylinder part, and

the cylinder part is not shorter than the first hub part in the axial direction of the rotary shaft.

8. The electric blower according to claim 7 , wherein

an outside diameter of the fastener is larger than an inside diameter of the first hub part,

the second inducer is secured to the rotary shaft by the fastener from an upper side of the cylinder part, and

an upper surface of the first hub part is disposed to be proximally covered by a lower surface of the faster.

9. The electric blower according to claim 1 , wherein the first blade parts of the first inducer and the second blade parts of the second inducer, and the second blade parts neighboring the first blade parts of the first inducer, overlap with each other.