Patent ID: 7745968

Claim:
A motor comprising: a sleeve having a flange portion on an outer circumference portion thereof and configured to rotatably support a rotor spindle; a sleeve holder configured to hold the sleeve; a rotor hub having an annular wall portion which has the same center axis as the rotor spindle and configured to rotate together with the rotor spindle; an inner body fixed in an inside of the annular wall portion so as to surround the sleeve and the sleeve holder, wherein the inner body has an annular protrusion portion which is sandwiched between the flange portion and one end portion of the sleeve holder, on an inner circumference portion thereof; a first thrust bearing portion formed between the annular protrusion portion and the flange portion, the first thrust bearing portion having a first groove, which is formed on a surface of the annular protrusion portion and the flange portion opposed to each other in an axial direction of the motor, for increasing the pressure of lubricant agent filled in the first thrust bearing portion, and supporting thrust loads using the first groove; and a second thrust bearing portion formed between the annular protrusion portion and the one end portion of the sleeve holder, the second thrust bearing portion having a second groove, which is formed on another surface of the annular protrusion portion and the end portion of the sleeve holder opposed to each other in the axial direction of the motor, for increasing the pressure of lubricant agent filled in the second thrust bearing portion, and supporting thrust loads using the second groove.