Tapered roller bearing
AssigneeKoninklijke Philips Electroncis N.V.
InventorsWilliam C. Brunnett, Ronald B. Sharpless
Life of this patent
Estimating the term…
Abstract
In a diagnostic system, having a rotating gantry (24) and a stationary gantry (22), a bearing race (50) rotates with surface portions having varying linear velocities in accordance with distance from an axis (A) of rotation. Tapered roller bearings (46) interface the bearing race (50) and are conically shaped to velocity match the variable linear surface velocity race (50). The race (50) preferably includes two faces, which provide both axial and radial supporting surfaces for the bearings (46) to interface. The bearings (46) are disposed about the race (50) in pairs. A drive motor (52) is connected to one of the bearings (46) to rotate the gantry (24).
Claims18
A diagnostic imaging device comprising:
- a first, stationary gantry;
- a second, rotating gantry having at least two bearing races, the second gantry rotating around a subject receiving region;
- and
- a plurality of tapered roller bearings for providing support to the rotating gantry to rotate around an axis of rotation;
- wherein the roller bearings have a taper angle φ defined by:
- ϕ
- =
- arcsin
-
- (
- d
- o
- -
- d
- 1
- 2
-
-
- L
- c
- )
- where do is a large end diameter of the bearing, di is a small end diameter of the bearing, and Lc is a length measured along a surface of the bearing between the large and small ends.
A method of diagnostic imaging comprising:
- supporting a rotating gantry, which surrounds a subject receiving region with a plurality of tapered roller bearings attached to a stationary gantry;
- rotating the gantry concurrently on the roller bearings, bearing races of the gantry contacting surfaces of the bearings;
- wherein
- a taper angle φ of the roller bearings by the relationship:
- ϕ
- =
- arcsin
-
-
- (
- d
- o
- -
- d
- i
- 2
-
- L
- c
- )
- where do is a larger end diameter of the bearing, di is a smaller end diameter of the bearing, and Lc is a length between the larger and smaller ends measured along a surface of the bearing.
A roller bearing for use in conjunction with a computed tomography scanner, the roller bearing comprising:
- a bearing race of a rotating gantry of the computed tomography scanner;
- an axle about which the bearing rotates;
- a tapered, conical body having a trapezoidal cross-section, the tapered surface of the body having a contact surface that interfaces with the bearing race of the rotating gantry of the computed tomography scanner, a taper angle φ of the bearing being defined by:
- ϕ
- =
- arcsin
-
- (
- d
- o
- -
- d
- 1
- 2
-
-
- L
- c
- )
- where do is a larger end diameter of the bearing, di is a smaller end diameter of the bearing, and Lc is the length between the later and smaller ends measured along the contact surface of the bearing;
- and
- a polymeric coating on the contact surface of the bearing body.
Dependencies are inferred from the claim text.