Taper roller bearing

A taper roller bearing comprising:

• an inner ring which includes a small flange that is positioned on one side in an axial direction and protrudes to an outer side in a radial direction, and a large flange that is positioned on the other side in the axial direction and protrudes to the outer side in the radial direction;
• an outer ring which is positioned on the outer side in the radial direction of the inner ring;
• a plurality of taper rollers which are positioned between the inner ring and the outer ring;
• and
• an annular cage which holds the plurality of taper rollers at an interval in the circumferential direction, wherein
• the cage includes a small-diameter annular portion which is positioned on the one side, a large-diameter annular portion which is positioned on the other side, and a plurality of column portions which link the small-diameter annular portion and the large-diameter annular portion to each other, a cylindrical inner surface of the small-diameter annular portion opposes an outer circumferential surface of the small flange in the radial direction at a position axially outward of the grooves, and an annular clearance is formed therebetween to limit inflow of lubricating oil,
• an inner surface in the radial direction of each of the column portions is positioned along a second virtual taper surface which is in the vicinity of a first virtual taper surface including center lines of the plurality of taper rollers or which fits the first virtual taper surface, across an entire length in a longitudinal direction of the column portions, and
• grooves are formed on the inner surface in the radial direction of the column portions, each of the grooves extending along the longitudinal direction of each of the column portions and being open on the other side and closed on the one side.