# US 10,117,627 B2 · System and method to maintain engagement of gears for X-ray imaging system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,117,627 B2 - Document ID: US10117627B2 - Status: Granted - Kind: B2 - Application number: 15/341,679 - Filed: 2016-11-02 - Published: 2018-05-03 - Granted: 2018-11-06 - Earliest claimed: 2016-11-02 - Assignees: General Electric Company - Applicants: General Electric Company - Inventors: Grant Richard Wagner; Curt Allen Zimmerman; Matthew Jason Evangelist - Web page: https://patentgrep.com/patent/US10117627B2 ## CPC - A61B 6/4435: {the source unit and the detector unit being coupled by a rigid structure} - A61B 6/032: {Transmission computed tomography [CT]} - A61B 6/037: {Emission tomography} - A61B 6/4417: {related to combined acquisition of different diagnostic modalities} - F16H 57/12: Arrangements for adjusting or for taking-up backlash not provided for elsewhere - F16H 2057/126: {Self-adjusting during operation, e.g. by a spring} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - F16H: GEARING ## Abstract An X-ray imaging system includes a gantry, rotatable about an axis of rotation, a radiation source mounted on the gantry and configured to emit radiation, and one or more detectors configured to detect the emitted radiation. The gantry includes a gear assembly coupled to a motor to enable rotation of the gantry, wherein the gear assembly comprises a gantry gear. The gantry includes an encoder for detecting position of the gantry, wherein the encoder comprises an encoder gear meshed with the gantry gear. The gantry also includes a gear re-engagement assembly configured to couple to the encoder and to force the encoder gear into correct engagement with the gantry gear when the encoder gear becomes disengaged from the gantry gear. As such, the gear re-engagement assembly keeps engagement of the encoder gear and the gantry gear to maintain the important gantry position tracking. ## Claims ### Claim 1 An X-ray imaging system, comprising: a gantry, rotatable about an axis of rotation; a radiation source mounted on the gantry and configured to emit radiation; and one or more detectors configured to detect the emitted radiation, wherein the gantry comprises: a gear assembly coupled to a motor to enable rotation of the gantry, wherein the gear assembly comprises a gantry gear; an encoder for detecting position of the gantry, wherein the encoder comprises an encoder gear meshed with the gantry gear; and a gear re-engagement assembly configured to couple to the encoder and to force the encoder gear into correct engagement with the gantry gear when the encoder gear becomes disengaged from the gantry gear. ### Claim 2 (depends on 1) The X-ray imaging system of claim 1 comprises a computed tomography (CT) system or a position emission tomography and CT combined (PET/CT) system. ### Claim 3 (depends on 1) The X-ray imaging system of claim 1, wherein the gear re-engagement assembly comprises: a counter weight coupled to the encoder; and a biasing member coupled to and spring-loaded by the counter weight, wherein the biasing member comprises a first portion configured to be adjustably coupled to the counter weight, and a second portion that has a terminal portion that is disposed at a clearance distance away from a wall of the gantry. ### Claim 4 (depends on 3) The X-ray imaging system of claim 3, wherein the clearance distance is approximately two millimeters when the encoder gear is correctly engaged with the gantry gear. ### Claim 5 (depends on 3) The X-ray imaging system of claim 3, wherein when the encoder gear becomes disengaged from the gantry gear, the biasing member of the re-engagement assembly contacts the wall of the gantry and forces the encoder gear into correct engagement with the gantry gear. ### Claim 6 (depends on 3) The X-ray imaging system of claim 3, wherein the clearance distance is adjustable by adjusting coupling between the first portion and the counter weight. ### Claim 7 (depends on 3) The X-ray imaging system of claim 3, wherein the first portion comprises one or more elongated slots that enable the first portion to be adjustably coupled to the counter weight. ### Claim 8 (depends on 3) The X-ray imaging system of claim 3, wherein the biasing member of the re-engagement assembly is made of steel, metal alloy, or composite. ### Claim 9 (depends on 3) The X-ray imaging system of claim 3, wherein an angle between the first portion and the second portion of the biasing member is approximately 145 degrees. ### Claim 10 A gear re-engagement system for a gantry of an X-ray imaging system, comprising: a biasing member; and a counter weight coupled to the biasing member, wherein the counter weight is configured to spring load the biasing member, and the counter weight is configured to couple to an encoder within the gantry and to force an encoder gear into correct engagement with a gantry gear within the gantry when the encoder gear becomes disengaged from the gantry gear. ### Claim 11 (depends on 10) The gear re-engagement system of claim 10, wherein when the encoder gear becomes disengaged from the gantry gear, the biasing member is configured to contact a wall of the gantry and to force the encoder gear into correct engagement with the gantry gear. ### Claim 12 (depends on 10) The gear re-engagement system of claim 10, wherein the biasing member comprises a first portion configured to be adjustably coupled to the counter weight, and a second portion that forms an angle with the first portion and has a terminal portion, which is configured to be disposed at a clearance distance from a wall of the gantry. ### Claim 13 (depends on 12) The gear re-engagement system of claim 12, wherein the clearance distance is adjustable by adjusting coupling between the first portion and the counter weight. ### Claim 14 (depends on 12) The gear re-engagement system of claim 12, wherein the clearance distance is approximately two millimeters when the encoder gear is correctly engaged with the gantry gear. ### Claim 15 (depends on 12) The gear re-engagement system of claim 12, wherein the angle between the first portion and the second portion of the biasing member is approximately 145 degrees. ### Claim 16 (depends on 12) The gear re-engagement system of claim 12, wherein the first portion comprises one or more elongated slots that enable the first portion to be adjustably coupled to the counter weight. ### Claim 17 A method for correcting gear jumping in a gantry of an X-ray imaging system comprising: coupling a gear re-engagement assembly to an encoder within an enclosure of the gantry; rotating the gantry about an axis of rotation based on a motor-driven gear assembly, comprising a gantry gear, wherein the gantry gear is correctly engaged with an encoder gear of the encoder; subjecting the gantry to vibration such that the encoder gear becomes disengaged from the gantry gear; and forcing the disengaged encoder gear into correct engagement with the gantry gear via the gear re-engagement assembly by contacting a spring-loaded biasing member of the gear re-engagement assembly with a wall of the enclosure. ### Claim 18 (depends on 17) The method of claim 17, wherein coupling the gear re-engagement assembly to the encoder comprises adjustably coupling the spring-loaded biasing member to a counter weight of the gear re-engagement assembly, wherein the counter weight is configured to load the spring-loaded biasing member, and the counter weight is configured to couple to the encoder within the gantry. ### Claim 19 (depends on 18) The method of claim 18, wherein the spring-loaded biasing member comprises one or more elongated slots to enable adjustably coupling the spring-loaded biasing member to the counter weight. ### Claim 20 (depends on 19) The method of claim 19, comprising adjusting a clearance distance between the spring-loaded biasing member and the wall of the enclosure by adjusting a position of the spring-loaded biasing member relative to the counter weight.