# US 8,770,022 B2 · Method and system for determining non-uniformity characteristics of a vehicle tire and rim > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,770,022 B2 - Document ID: US8770022B2 - Status: Granted - Kind: B2 - Application number: 13/432,832 - Filed: 2012-03-28 - Published: 2012-07-26 - Granted: 2014-07-08 - Earliest claimed: 2008-06-09 - Assignees: Hunter Engineering Company - Applicants: Michael Wayne Douglas; William B. Feero - Inventors: Michael Wayne Douglas; William B. Feero - Web page: https://patentgrep.com/patent/US8770022B2 ## CPC - G01M 17/022: {the tyre co-operating with rotatable rolls} - G01M 1/16: by oscillating or rotating the body to be tested - G01M: TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR ## Abstract A method and system for a wheel assembly service system are provided. The system includes a rotatable spindle configured to receive a wheel assembly wherein the wheel assembly includes at least a rim and a tire. The system further includes a load device configured to apply a load to the tire during a rotation of the wheel assembly on the spindle, and a controller configured to determine a first force variation vector of the wheel assembly, prompt a user to rotate the tire with respect to the rim, determine a second force variation vector of the wheel assembly with the tire rotated with respect to the rim, and determine a force variation of at least one of the tire and the wheel using the first and second force variation vectors. The system also outputs at least one of the determined force variation vector values. ## Claims ### Claim 1 A tire changer comprising: a rotatable spindle configured to receive a wheel assembly, the wheel assembly comprising at least a rim and a tire; and a controller configured to: determine a first non-uniformity of the wheel assembly; initiate rotation of the tire with respect to the rim; determine a second non-uniformity of the wheel assembly with the tire rotated with respect to the rim; and determine a non-uniformity component associated with the tire utilizing said first determined non-uniformity and said second determined non-uniformity. ### Claim 2 (depends on 1) A tire changer in accordance with claim 1 wherein said controller is further configured to determine a non-uniformity component associated with the rim. ### Claim 3 A method of determining force variation attributable to a tire in a wheel assembly wherein the tire is coupled to a rim, the method implemented on a tire changer including a controller, method comprising: determining a first force variation of the wheel assembly while the tire is in a first rotational position with respect to the rim; rotating the tire with respect to the rim to a second rotational position with respect to the rim; determining a second force variation of the wheel assembly while the tire is in the second rotational position; and determining, with the controller, a force variation component associated with the tire using the determined first force variation and the determined second force variation. ### Claim 4 (depends on 3) A method of measuring non-uniformity of a wheel assembly in accordance with claim 3 further comprising determining a force variation component associated with the rim. ### Claim 5 A wheel assembly service system comprising: a rotatable spindle configured to receive a wheel assembly, the wheel assembly comprising at least a rim and a tire; and a controller configured to: determine a first non-uniformity of the wheel assembly; initiate rotation of the tire with respect to the rim; determine a second non-uniformity of the wheel assembly with the tire rotated with respect to the rim; and determine a non-uniformity component associated with the rim utilizing said first determined non-uniformity and said second determined non-uniformity. ### Claim 6 (depends on 5) A wheel assembly service system in accordance with claim 5 wherein said controller is further configured to determine a non-uniformity component associated with the tire. ### Claim 7 (depends on 5) A wheel assembly service system in accordance with claim 5, wherein the wheel assembly service system is configured as a tire changer machine. ### Claim 8 (depends on 5) A wheel assembly service system in accordance with claim 5, wherein the wheel assembly service system is configured as a wheel balancer machine. ### Claim 9 A method for measuring the non-uniformity of a wheel assembly that includes a tire coupled to a rim, said method implemented with a wheel assembly service system including a controller, and said method comprising: determining a first non-uniformity of the wheel assembly; rotating the tire with respect to the rim; determining a second non-uniformity of the wheel assembly with the tire rotated with respect to the rim; and determining, with the controller, a non-uniformity component associated with the rim utilizing the determined first non-uniformity and the determined second non-uniformity. ### Claim 10 (depends on 9) A method in accordance with claim 9 further comprising determining a non-uniformity component associated with the tire. ### Claim 11 A wheel assembly service system comprising: a rotatable spindle configured to receive a wheel assembly, the wheel assembly including at least a rim and a tire; and a controller configured to determine a force variation component associated with at least one of the rim and the tire without measuring a rim runout; wherein the wheel assembly service system is configured as a tire changer machine. ### Claim 12 (depends on 11) The wheel assembly service system of claim 11, wherein the controller is further configured to: determine a first force variation of the wheel assembly; and initiate rotation of the tire with respect to the rim. ### Claim 13 (depends on 11) The wheel assembly service system of claim 11, wherein the controller is further configured to: determine a second force variation of the wheel assembly with the tire rotated with respect to the rim; and determine a force variation component associated with at least one the tire and the rim utilizing said determined first force variation and said second force variation. ### Claim 14 (depends on 11) A wheel assembly service system in accordance with claim 11, wherein the wheel assembly service system further includes a load device configured to apply a load to the tire during a rotation of the wheel assembly on the spindle. ### Claim 15 A wheel assembly service system comprising: a rotatable spindle configured to receive a wheel assembly, the wheel assembly including at least a rim and a tire; and a controller configured to, without measuring a rim runout, determine a first non-uniformity component associated with the rim and a second non-uniformity component associated with the tire. ### Claim 16 (depends on 15) A wheel assembly service system of claim 15, wherein the wheel assembly service system is configured as a tire changer machine. ### Claim 17 (depends on 15) A wheel assembly service system in accordance with claim 15, wherein the wheel assembly service system is configured as a wheel balancer machine. ### Claim 18 (depends on 15) A wheel assembly service system of claim 15, wherein the wheel assembly service system further includes a load device configured to apply a load to the tire during a rotation of the wheel assembly on the spindle.