Rotary bearing assembly for CT scanner gantry

• US 6,337,894 B1
• Filed: 01/18/2001
• Issued: 01/08/2002
• Est. Priority Date: 09/20/2000
• Status: Active Grant

• Current Assignee: Analogic Corporation
• Original Assignee: Analogic Corporation
• Inventors: Tybinkowski, Andrew P., Nemirovsky, Lidia, Duffy, Michael J.
• Primary Examiner(s): DUNN, DREW A
• Application Number:
  US09/764,797
• Time in Patent Office: 355 Days
• Field of Search: 378/15, 378/4, 378/193, 378/205
• US Class Current: 378/4
• CPC Class Codes: A61B 6/035 Mechanical aspects of CT
• CPC Class Codes: F16C 19/183 with two rows at opposite angles
• CPC Class Codes: F16C 2300/14 Large applications, e.g. bearings having an inner diameter exceeding 500 mm
• CPC Class Codes: F16C 2316/10 in medical appliances, e.g. in diagnosis, dentistry, instruments, prostheses, medical imaging appliances
• CPC Class Codes: F16C 33/61 formed by wires

Abstract

The present disclosure provides a gantry of a CT scanner. The gantry includes an annular outer support having a radially inwardly facing, continuous circumferencial bearing chamber, an annular drum concentrically positioned within the outer support and having a continuous circumferential bearing lip radially extending into the bearing chamber of the outer support to define two circumferential bearing runs within the bearing chamber, and an annular disk extending radially inwardly from an inner circumferential surface of the drum. The disk is adapted to receive and support computed tomography components. The gantry also includes roller bearings in the bearing runs rotatably supporting the drum within the outer support, such that the drum and the disk are rotatable about a rotation axis of the drum.

Claims

1. A gantry of a CT scanner comprising:

a) an annular outer support having a radially inwardly facing, continuous circumferencial bearing chamber;

b) an annular drum concentrically positioned within the outer support and having a continuous circumferential bearing lip radially extending into the bearing chamber of the outer support to define two circumferential bearing runs within the bearing chamber;

c) an annular disk extending radially inwardly from an inner circumferential surface of the drum, the disk adapted to receive and support computed tomography components; and

d) roller bearings contained in the bearing runs rotatably supporting the drum within the outer support, such that the drum and the disk are rotatable about a rotation axis of the drum.

2. A gantry according to claim 1, wherein the drum axially extends between first and second ends, and the bearing lip is equally spaced from the ends.

3. A gantry according to claim 1, wherein the annular disk is concentrically aligned with the bearing lip of the drum.

4. A gantry according to claim 1, wherein the drum and annular disk are unitary.

5. A gantry according to claim 1, wherein the roller bearings comprise spherical ball bearings.

6. A gantry according to claim 1, further comprising bearing wires circumferentially extending within the bearings runs and guiding the roller bearings.

7. A gantry according to claim 6, wherein bearing wires are positioned on either side of the bearing lip, and bearing wires are positioned in two circumferential corners defined by the bearing chamber.

8. A gantry according to claim 1, wherein the annular outer support includes first and second annular pieces axially joined to define the bearing chamber.

9. A gantry according to claim 8, wherein the first and second annular pieces are secured together with preloaded bolts.

10. A gantry according to claim 1, wherein the annular outer support includes grease fittings providing communication with the bearing chamber.

11. A gantry according to claim 1, further comprising an annular seal between the annular outer support and the annular drum.

12. A gantry according to claim 1, wherein the annular disk includes apertures for receiving computer tomography components.

13. A gantry according to claim 1, wherein a portion of the radially outermost surface of the rotatable drum is sheaved.

14. A gantry according to claim 13, further comprising:

a motor having a sheaved drive pulley; and

a belt mounted between the sheaved drive pulley and the sheaved portion of the drum.

15. A gantry according to claim 1, further including diametrically opposed mounts extending radially outwardly from the outer support for mounting the gantry on a stand, the mounts aligned with the disk.

16. A CT scanner including a gantry according to claim 1, and further comprising:

a stand supporting the gantry; and

x-ray tomography components operatively mounted on the annular disk of the gantry for rotation therewith about the rotation axis.

17. A gantry according to claim 1, wherein the disk is adapted to receive x-ray tomography components on both sides of the disk.

18. A gantry according to claim 1, wherein the disk is adapted to allow at least some of x-ray tomography components to extend through the disk.

19. A gantry according to claim 1, wherein the disk is adapted to so that components fixedly mounted on the disk will be substantially balanced for rotation with the disk about the rotation axis.

20. A gantry according to claim 1, wherein the disk, the drum and the outer support are formed of the same light-weight, rigid metal.