Dynamic bearing device

Abstract

A dynamic bearing device is provided, which can prevent abrasion powder generated when a sealing member is pushed into an inner circumference of a housing from entering the housing. A sealing member is inserted into an inner circumference of an opening of a housing with an adhesive interposed therebetween The adhesive moving forward in a pushing direction of the sealing member is retained by a capillary action in a lower tapered space between an outer circumference of the sealing member and the inner circumference of the housing. Abrasion powder is captured by the adhesive in the tapered space so as to be confined in the adhesive as a result of the setting of the adhesive.

1 . A dynamic bearing device comprising:
 a housing;   a bearing sleeve fixed to an inner circumference of the housing;   a rotary member including a shaft portion inserted into the bearing sleeve;   a bottom member for closing an opening of the housing;   a radial bearing portion for generating a pressure in a radial direction in a radial bearing gap between the bearing sleeve and the shaft portion by a dynamic pressure effect of a lubricating fluid; and   a thrust bearing portion for generating a pressure in a thrust direction in a thrust bearing gap formed between the rotary member and the housing by a dynamic pressure effect of the lubricating fluid,   wherein the bottom member is pushed into the opening of the housing so as to be fixed thereto with an adhesive interposed therebetween.   
   
   
       2 . A dynamic bearing device according to  claim 1 , having an inner tapered space for retaining the adhesive between the outer circumference of the bottom member and the inner circumference of the housing, the inner tapered space being adjacent to a press-fit part of the bottom member on the inner side of the housing. 
   
   
       3 . A dynamic bearing device according to  claim 1 , having an outer tapered space for retaining the adhesive between the outer circumference of the bottom member and the inner circumference of the housing, the outer tapered space being adjacent to a press-fit part of the bottom member on the outer side of the housing. 
   
   
       4 . A dynamic bearing device according to  claim 1 , having an inner tapered space, for retaining the adhesive, being adjacent to a press-fit part of the bottom member on the inner side of the housing so as to retain the adhesive and the outer tapered space, for retaining the adhesive, being adjacent to the press-fit part of the bottom member on the outer side of the housing between the outer circumference of the bottom member and the inner circumference of the housing. 
   
   
       5 . A dynamic bearing device according to  claim 3 , having a step for the inner circumference of the housing, the step being located in the outer tapered space to face the exterior of the housing. 
   
   
       6 . A dynamic bearing device according to  claim 4 , having a step for the inner circumference of the housing, the step being located in the outer tapered space to face the exterior of the housing. 
   
   
       7 . A dynamic bearing device according to  claim 2 , wherein a tapered surface for forming the tapered space is provided on the outer circumference of the bottom member. 
   
   
       8 . A dynamic bearing device according to  claim 3 , wherein a tapered surface for forming the tapered space is provided on the outer circumference of the bottom member. 
   
   
       9 . A dynamic bearing device according to  claim 4 , wherein a tapered surface for forming the tapered space is provided on the outer circumference of the bottom member. 
   
   
       10 . A dynamic bearing device according to  claim 5 , wherein a tapered surface for forming the tapered space is provided on the outer circumference of the bottom member. 
   
   
       11 . A dynamic bearing device according to  claim 6 , wherein a tapered surface for forming the tapered space is provided on the outer circumference of the bottom member. 
   
   
       12 . A method of fabricating the dynamic pressure bearing according to  claim 1 , comprising the steps of: applying an adhesive onto an inner circumference of a housing; and pushing a bottom member into the inner circumference of the housing, to which the adhesive has been applied.