Combination bearing

Patent metadata

Field	Value
Publication number	US-10145413-B2
Application number	US-201715653841-A
Country	US
Kind code	B2
Filing date	Jul 19, 2017
Priority date	Jul 27, 2016
Publication date	Dec 4, 2018
Grant date	Dec 4, 2018

Abstract

Rolling bearings are stacked with their center lines extending in a vertical direction. Each of the rolling bearings has an inner ring, an outer ring, a plurality of balls, and an annular cage. Each of the rolling bearings has a structure that induces, upon rotation, an action that causes lubricating oil to flow upward along the outer ring in the annular space. The cage has an annular portion provided adjacently below the balls to prevent air from moving to the outer ring side from the inner ring side.

First claim

What is claimed is:

1. A combination bearing comprising a plurality of rolling bearings stacked with their center lines extending in a vertical direction, wherein
each of the rolling bearings has an inner ring, an outer ring, a plurality of rolling elements provided in an annular space between the inner ring and the outer ring, and an annular cage retaining the plurality of rolling elements,
each of the rolling bearings has a structure that induces, upon rotation, an action that causes lubricating oil to flow upward along the outer ring in the annular space, and
the cage has an upper annular portion and a lower annular portion provided adjacently above and below the rolling elements to suppress air from moving to the outer ring side from the inner ring side,
the outer ring has, on an inner circumferential side thereof, an outer raceway, a lower shoulder portion adjacent a lower side of the outer raceway, and a diameter increasing surface that increases in diameter from an upper side of the outer raceway as it extends upward,
the lower annular portion of the cage is positioned closer to an outer circumference face of the inner ring than the lower shoulder portion in a direction of the lower shoulder portion.

2. The combination bearing according to claim 1 , wherein
the lower annular portion of a lowermost rolling bearing of the rolling bearings extends downward to a position lower than a lower surface of the inner ring.

3. The combination bearing according to claim 2 , wherein
the cage has a plurality of cage bars that connect the upper annular portion and the lower annular portion and are inclined radially outward as the cage bars extend upward.

4. The combination bearing according to claim 3 , wherein
the upper annular portion of the cage has a cylindrical shape that is vertically linear.

5. The combination bearing according to claim 1 , wherein
the cage has a plurality of cage bars that connect the upper annular portion and the lower annular portion and are inclined radially outward as the cage bars extend upward.

6. The combination bearing according to claim 5 , wherein
the upper annular portion of the cage has a cylindrical shape that is vertically linear.

7. The combination bearing according to claim 1 , wherein
the upper annular portion of the cage has a tapered shape so as to decrease in diameter as the upper annular portion extends upward.

8. The combination bearing according to claim 1 , wherein
the inner ring has an upper shoulder portion that is larger in outside diameter than a lower shoulder portion, and
the lower annular portion of the cage of a second lowest or higher rolling bearing of the rolling bearings faces, in the axial direction, the upper shoulder portion of the inner ring of the rolling bearing positioned under the lower annular portion, with a clearance between the lower annular portion and the upper shoulder portion.

9. The combination bearing according to claim 1 , wherein
the lower annular portion of the lowermost rolling bearing faces the lower surface of the inner ring.

Assignees

• Jtekt Corp

Inventors

• Okamoto Daisuke
• Toda Takuya

Classifications

• F16C19/541

  Systems consisting of juxtaposed rolling bearings including at least one angular contact bearing · CPC title

• F16C33/664 Primary

  Retaining the liquid in or near the bearing · CPC title

• F16C2352/00

  Apparatus for drilling · CPC title

• F16C19/225

  Details of the ribs supporting the end of the rollers · CPC title

• E21B4/003

  Bearing, sealing, lubricating details (for roller bits E21B10/22) · CPC title