Hub Unit Bearing

Abstract

Provided is a hub unit bearing wherein a cover can be firmly fitted with an outer ring member, and it is difficult for foreign matter to enter inside through a water drainage hole formed in the cover. The cover that covers the inside end section in the axial direction of the hub unit bearing includes a disk section, a small-diameter cylindrical section bent in the axial direction from the outer perimeter edge section of the disk section and a large-diameter cylindrical section. A cut and raised section that is cut and raised toward the inside in the radial direction is formed in the small-diameter cylindrical section, and a water drainage hole that passes through from inside to outside the cover is provided in the portion that is cut and separated from the small-diameter cylindrical section.

1 . A hub unit bearing comprising:
 an outer ring member, which is a stationary ring;   an inner ring member, which is a rotating ring that can rotate relative to the outer ring member via a plurality of rolling elements; and   a cover that covers the inside end sections in the axial direction of the outer ring member and inner ring member,   the cover having:   a disk section; and   a cylindrical section that is bent outward in the axial direction from the outer perimeter edge section of the disk section, and is fitted with and fastened to the outer ring member, and   the cylindrical section having a cut and raised section that is formed in part in the circumferential direction of the cylindrical section by being cut and raised toward the inside or outside in the radial direction of the cylindrical section, such that this cut and raised section forms a water drainage hole that passes through from the inside to the outside of the cover.   
     
     
         2 . The hub unit bearing according to  claim 1 , wherein
 the cut and raised section is cut and raised by cutting two cutting-plane lines along the circumferential direction of the cylindrical section, and water drainage holes are formed on both sides in the axial direction of the cut and raised section.   
     
     
         3 . The hub unit bearing according to  claim 1 , wherein the cut and raised section is cut and raised by cutting one cutting-plane line along the circumferential direction of the cylindrical section such that one side in the axial direction of the cut and raised section is continuous with the cylindrical section, and the water drainage hole is formed on the other side in the axial direction. 
     
     
         4 . The hub unit bearing according to  claim 3 , wherein
 the cut and raised section has an L-shaped cross section in the cross section in the axial direction of the cover.   
     
     
         5 . The hub unit bearing according to  claim 3 , wherein
 the cut and raised section has a linear shaped cross section in the cross section in the axial direction of the cover.   
     
     
         6 . A hub unit bearing comprising:
 an outer ring member, which is a stationary ring;   an inner ring member, which is a rotating ring that can rotate relative to the outer ring member via a plurality of rolling elements; and   a cover that covers the inside end sections in the axial direction of the outer ring member and inner ring member,   the cover having:   a disk section; and   a cylindrical section that is bent outward in the axial direction from the perimeter edge section of the disk section, and is fitted with and fastened to the outer ring member, and   the cylindrical section having a groove section that is recessed toward the inside or the outside in the radial direction along the axial direction, and a water drainage hole that passes through from the inside to the outside of the cover is formed in the portion between the groove section and the outer ring member.   
     
     
         7 . The hub unit bearing according to  claim 6 , wherein
 the groove section is formed in the cylindrical section such that the groove section is parallel with the axial direction of the cover.   
     
     
         8 . The hub unit bearing according to  claim 6 , wherein
 the groove section is formed in the cylindrical section such that the groove section is inclined with respect to the axial direction of the cover.   
     
     
         9 . A hub unit bearing comprising:
 an outer ring member, which is a stationary ring;   an inner ring member, which is a rotating ring that can rotate relative to the outer ring member via a plurality of rolling elements; and   a cover that covers the inside end sections in the axial direction of the outer ring member and inner ring member,   the cover having:   a disk section; and   a cylindrical section that is bent outward in the axial direction from the perimeter edge section of the disk section, and is fitted with and fastened to the outer ring member, and   the cylindrical section having at least: a large-diameter cylindrical section that is fitted onto and fastened to the inside end section in the axial direction of the outer ring member; a side wall section that is bent inward in the radial direction from the inside end section in the axial direction of the large-diameter cylindrical section, with the outside surface in the axial direction thereof coming in contact with the surface on the inside end in the axial direction of the outer ring member; and a small-diameter cylindrical section that is continuous with the disk section and is bent inward in the axial direction from the inside end section in the radial direction of the side wall section, and   a water drainage hole is formed in a portion in part in the circumferential direction of the cylindrical section that connects the small-diameter cylindrical section and the side wall section, and the bottom end section of the water drainage hole located in the middle section in the radial direction of the side wall section is located further downward then the bottom end section of the inner circumferential surface of the inside end section in the axial direction of the outer ring member.   
     
     
         10 . The hub unit bearing according to  claim 1 , further comprising:
 a seal member made of an elastic material and that is provided on the inside end section in the radial direction of the disk section, the edge on the tip end of a seal lip of the seal member coming in contact all the way around the surface of the inner ring member or a separate member that rotates together with the inner ring member.   
     
     
         11 . The hub unit bearing according to  claim 1 , further comprising:
 an inner-diameter cylindrical section that is bent outward in the axial direction from the inside end section in the radial direction of the disk section,   the inner circumferential surface of the inner-diameter cylindrical section functioning as a seal surface with which the edge on the tip end of the seal member made of elastic material, which is a seal that is provided between the cover and the inner ring member or separate member that rotates together with the inner ring member, comes in sliding contact with or closely faces all around in the circumferential direction.   
     
     
         12 . The hub unit bearing according to  claim 1 , wherein
 the water drainage hole, during operation, is located within a range of ±35° in the circumferential direction with an intersection point where a plumb line that passes through the center axis of the cover crosses the bottom end section of the cover.   
     
     
         13 . The hub unit bearing according to  claim 1 , wherein
 an encoder is provided on the outer circumferential surface of the inside end section in the axial direction of the inner ring member, and a sensor having a detecting unit that faces the encoder is provided in the cylindrical section or part of the disk section of the cover.   
     
     
         14 . The hub unit bearing according to  claim 6 , further comprising:
 a seal member made of an elastic material and that is provided on the inside end section in the radial direction of the disk section, the edge on the tip end of a seal lip of the seal member coming in contact all the way around the surface of the inner ring member or a separate member that rotates together with the inner ring member.   
     
     
         15 . The hub unit bearing according to  claim 9 , further comprising:
 a seal member made of an elastic material and that is provided on the inside end section in the radial direction of the disk section, the edge on the tip end of a seal lip of the seal member coming in contact all the way around the surface of the inner ring member or a separate member that rotates together with the inner ring member.   
     
     
         16 . The hub unit bearing according to  claim 6 , further comprising:
 an inner-diameter cylindrical section that is bent outward in the axial direction from the inside end section in the radial direction of the disk section,   the inner circumferential surface of the inner-diameter cylindrical section functioning as a seal surface with which the edge on the tip end of the seal member made of elastic material, which is a seal that is provided between the cover and the inner ring member or separate member that rotates together with the inner ring member, comes in sliding contact with or closely faces all around in the circumferential direction.   
     
     
         17 . The hub unit bearing according to  claim 9 , further comprising:
 an inner-diameter cylindrical section that is bent outward in the axial direction from the inside end section in the radial direction of the disk section,   the inner circumferential surface of the inner-diameter cylindrical section functioning as a seal surface with which the edge on the tip end of the seal member made of elastic material, which is a seal that is provided between the cover and the inner ring member or separate member that rotates together with the inner ring member, comes in sliding contact with or closely faces all around in the circumferential direction.   
     
     
         18 . The hub unit bearing according to  claim 6 , wherein
 the water drainage hole, during operation, is located within a range of ±35° in the circumferential direction with an intersection point where a plumb line that passes through the center axis of the cover crosses the bottom end section of the cover.   
     
     
         19 . The hub unit bearing according to  claim 9 , wherein
 the water drainage hole, during operation, is located within a range of ±35° in the circumferential direction with an intersection point where a plumb line that passes through the center axis of the cover crosses the bottom end section of the cover.   
     
     
         20 . The hub unit bearing according to  claim 6 , wherein
 an encoder is provided on the outer circumferential surface of the inside end section in the axial direction of the inner ring member, and a sensor having a detecting unit that faces the encoder is provided in the cylindrical section or part of the disk section of the cover.   
     
     
         21 . The hub unit bearing according to  claim 9 , wherein
 an encoder is provided on the outer circumferential surface of the inside end section in the axial direction of the inner ring member, and a sensor having a detecting unit that faces the encoder is provided in the cylindrical section or part of the disk section of the cover.