Spindle motor
AssigneeMatsushita Electric Industrial Co., Ltd.
InventorsTakao Yoshitsugu, Shoichi Yoshikawa
Life of this patent
Estimating the term…
Abstract
A downsized spindle motor of excellent abrasion and shock resistance is provided. A shaft is fit into a sleeve. A flange is fixed to an end of the shaft. A radial bearing is formed on faces of the shaft and the sleeve, which faces are opposite and close to each other. A face of the flange closely faces a face of a thrust plate, thereby forming a thrust bearing. Another face of the thrust plate is caulked with a tip of the sleeve. The tip of the sleeve and the thrust plate are fixed to each other by an adhesive. A tapering section is provided at an upper end of the sleeve.
Claims44
A spindle motor comprising:
- a shaft;
- a flange fixed to a first axial end of said shaft and having a diameter greater than that of said shaft;
- a cylindrical sleeve to which said shaft is fit, said sleeve having a tapering section at an upper end portion of said sleeve, said tapering section being inclined generally upwardly and outwardly in a direction from an inner surface of said sleeve toward an outer surface of said sleeve, and said tapering section having a dimension in a radial direction of said sleeve that is greater than a dimension of said tapering section in an axial direction of said shaft;
- a radial bearing space defined between said inner surface of said sleeve and an outer surface of said shaft;
- a rotor hub fixed to a second axial end of said shaft and disposed opposite to said upper end portion of said sleeve;
- a thrust plate disposed opposite said flange;
- and
- a thrust bearing space defined between an upper surface of said thrust plate and a lower surface of said flange, wherein
- lubricant is to be retained in said thrust bearing space.
The spindle motor according to claimer 31, wherein
- said tapering section includes a first portion extending from said inner surface of said sleeve to a position intermediate said inner surface and said outer surface of said sleeve, and also includes a second portion extending between said position and said outer surface of said sleeve, and
- said step is positioned between said first portion and said second portion.
A spindle motor comprising:
- a shaft;
- a flange fixed to a first axial end of said shaft and having a diameter greater than that of said shaft;
- a cylindrical sleeve to which said shaft is fit, said sleeve having a tapering section at an upper end portion of said sleeve, said tapering section being inclined generally upwardly and outwardly in a direction from an inner surface of said sleeve toward an outer surface of said sleeve at an angle of about 5° relative to a plane that is transverse to said shaft and between said first and second axial ends of said shaft;
- a radial bearing space defined between said inner surface of said sleeve and an outer surface of said shaft;
- a rotor hub fixed to a second axial end of said shaft and disposed opposite to said upper end portion of said sleeve;
- a thrust plate disposed opposite said flange;
- and
- a thrust bearing space defined between an upper surface of said thrust plate and a lower surface of said flange, wherein
- lubricant is to be retained in said thrust bearing space.
Dependencies are inferred from the claim text.