Patent ID: 6244749
Filing Date: 2001-06-12
Classification: F16C,Y10S

Abstract:
A dynamic pressure bearing device comprising:a shaft member;a bearing member disposed so as to be relatively rotated with respect to said shaft member;a dynamic pressure generating section formed in at least one of said shaft member and bearing member, said dynamic pressure generating section including:a plurality of dynamic pressure generating portions respectively arranged intermittently along the peripheral direction of one of said shaft member and bearing member;a projecting surface for pressurizing a lubricating fluid, said projecting surface projects in the radial direction of one of said shaft member and bearing member toward the other; anda plurality of negative pressure cancel portions for canceling negative pressures generated together with the dynamic pressures that are generated by said plurality of dynamic pressure generating portions, said each negative pressure cancel portion interposed between the mutually adjoining ones of said plurality of dynamic pressure generating portions and, said negative pressure cancel portions being respectively formed of porous material and being structured in such a manner that a large number of pores of said porous material for supplying/absorbing said lubricating fluid are exposed to the surfaces of said negative pressure cancel portions.