# US 2018/0321099 A1 · Measuring device and method for ascertaining operating parameters at shafts > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0321099 A1 - Document ID: US20180321099A1 - Status: Published application - Kind: A1 - Application number: 15/771,851 - Filed: 2017-01-31 - Published: 2018-11-08 - Earliest claimed: 2016-02-01 - Assignees: Schaeffler Technologies AG & Co. KG - Applicants: Schaeffler Technologies AG & Co. KG - Inventors: Christoph Weeth; Frank Benkert - Web page: https://patentgrep.com/patent/US20180321099A1 ## CPC - G01L 5/136: {Force sensors associated with a vehicle traction coupling (vehicle connections B60D; control of vehicle brakes B60T)} - G01L 3/24: Devices for determining the value of power, e.g. by measuring and simultaneously multiplying the values of torque and revolutions per unit of time, by multiplying the values of tractive or propulsive force and velocity - G01L 5/0095: {measuring work or mechanical power} - G01L 5/225: {to foot actuated controls, e.g. brake pedals} - G01L: MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE (weighing G01G) ## Abstract Measuring devices and methods for ascertaining an operating parameter at a shaft are disclosed. The shaft may be supported by at least one bearing. In one example, the measuring device includes at least one first sensor element configured to detect an absolute angle of the shaft and at least one second sensor element configured to detect a change in a distance of the shaft from the at least one second sensor element. A computing device may be configured to calculate one or more operating parameters at the shaft from the absolute angle of the shaft and the change in the distance. ## Claims ### Claim 1 A measuring device for ascertaining an operating parameter at a shaft, the shaft being supported by at least one bearing, the measuring device comprising: at least one first sensor element configured to detect an absolute angle of the shaft; at least one second sensor element configured to detect a change in a distance of the shaft from the at least one second sensor element; and a computing device configured to calculate one or more operating parameters at the shaft from the absolute angle of the shaft and the change in the distance. ### Claim 2 (depends on 1) The measuring device as claimed in claim 1, wherein, for the detection of the absolute angle, an encoder is arranged radially on the shaft or radially on a component rotationally fixedly connected to the shaft. ### Claim 3 (depends on 2) The measuring device as claimed in claim 2, wherein the rotationally fixedly connected component is an extension of an inner ring of the bearing. ### Claim 4 (depends on 1) The measuring device as claimed in claim 1, wherein, for the detection of the absolute angle, an encoder is arranged axially on the shaft or axially on a component rotationally fixedly connected to the shaft. ### Claim 5 (depends on 4) The measuring device as claimed in claim 4, wherein the rotationally fixedly connected component is an inner ring of the bearing or a seal. ### Claim 6 (depends on 1) The measuring device as claimed in claim 1, wherein the at least one bearing has a bearing point, and wherein the at least one second sensor element is arranged at the bearing point. ### Claim 7 (depends on 1) The measuring device as claimed in claim 1, wherein the at least one bearing has a first and a second bearing point, wherein the measuring device comprises at least two second sensor elements, and wherein one each of the second sensor elements is arranged at the first and the second bearing point. ### Claim 8 (depends on 1) The measuring device as claimed in claim 1, wherein the at least one bearing has a first and a second bearing point, and wherein the at least one second sensor element is arranged between the first and the second bearing point. ### Claim 9 (depends on 8) The measuring device as claimed in claim 8, wherein the at least one second sensor element is arranged centrally between the first and the second bearing point. ### Claim 10 (depends on 1) The measuring device as claimed in claim 1, wherein the at least one first sensor element and/or the at least one second sensor element are/is formed as an eddy current sensor. ### Claim 11 (depends on 1) The measuring device as claimed in claim 1, wherein the at least one first sensor element and the at least one second sensor element are integrated structurally in one sensor unit. ### Claim 12 A method for ascertaining an operating parameter at a shaft, wherein a force can be introduced into the shaft via at least one crank arm rotationally fixedly connected to the shaft, wherein the force can be broken down into a tangential force and a radial force, wherein a line of action of the radial force is directed toward a center of the shaft, and wherein a line of action of the tangential force forms a right angle with the line of action of the radial force, the method comprising: detecting an absolute angle of the shaft; detecting a change in a distance of the shaft from a sensor element; and calculating the operating parameter at the shaft from the absolute angle and the change in the distance, wherein the force is calculated from the change in the distance, wherein the tangential force is calculated from the force and the absolute angle, and wherein the operating parameter at the shaft is determined by the tangential force. ### Claim 13 A measuring device for ascertaining a torque or a power at a shaft of a bottom bracket bearing arrangement of a bicycle or electric bicycle, the shaft being supported by a bearing, the measuring device comprising: a first sensor element configured to detect an absolute angle of the shaft; a second sensor element configured to detect a change in a distance of the shaft from the second sensor element; and a computing device configured to calculate the torque or the power at the shaft from the absolute angle of the shaft and the change in the distance. ### Claim 14 (depends on 13) The measuring device as claimed in claim 13, wherein, for the detection of the absolute angle, an encoder is arranged radially on the shaft or radially on a component rotationally fixedly connected to the shaft. ### Claim 15 (depends on 13) The measuring device as claimed in claim 13, wherein, for the detection of the absolute angle, an encoder is arranged axially on the shaft or axially on a component rotationally fixedly connected to the shaft. ### Claim 16 (depends on 13) The measuring device as claimed in claim 13, wherein the bearing has a bearing point, and wherein the second sensor element is arranged at the bearing point. ### Claim 17 (depends on 13) The measuring device as claimed in claim 13, wherein the bearing has a first and a second bearing point, wherein the measuring device comprises at least two second sensor elements, and wherein one each of the second sensor elements is arranged at the first and the second bearing point. ### Claim 18 (depends on 13) The measuring device as claimed in claim 13, wherein the bearing has a first and a second bearing point, and wherein the second sensor element is arranged between the first and the second bearing point. ### Claim 19 (depends on 13) The measuring device as claimed in claim 13, wherein the first sensor element and/or the second sensor element are/is formed as an eddy current sensor. ### Claim 20 (depends on 13) The measuring device as claimed in claim 13, wherein the first sensor element and the second sensor element are integrated structurally in one sensor unit.