TORQUE MEASURING DEVICE AND MANUFACTURING METHOD THEREOF

    公开(公告)号:US20230280223A1

    公开(公告)日:2023-09-07

    申请号:US18176098

    申请日:2023-02-28

    IPC分类号: G01L3/10

    CPC分类号: G01L3/102 G01L3/108

    摘要: The manufacturing method includes: performing testing of samples having the same configuration as the torque measuring device to be manufactured to find a coil balance Cb that is a ratio (R1×R3)/(R2×R4) of a product R1×R3 of resistance values R1 and R3 of one pair of opposite sides of the four sides of a bridge circuit 8, and a product R2×R4 of resistance values R2 and R4 of another pair of opposite sides of the four sides, and a temperature change rate VT of output voltage Vo of a sensor portion 4, and acquiring a relationship X between the coil balance Cb and the temperature change rate VT from the test results; and measuring the resistance values R1, R2, R3, R4 of the four sides to find the coil balance Cb to find the temperature change rate VT from the relationship X for the torque measuring device to be manufactured.

    METHOD OF MANUFACTURING MAGNETOSTRICTIVE TORQUE SENSOR SHAFT

    公开(公告)号:US20220026294A1

    公开(公告)日:2022-01-27

    申请号:US17416850

    申请日:2019-12-11

    申请人: NSK LTD.

    摘要: A method of manufacturing a magnetostrictive torque sensor shaft (100) to which a sensor portion (2) of a magnetostrictive torque sensor (1) is mounted. The method includes heat treatment step of subjecting an iron-based shaft member to a carburizing, quenching, and tempering process, and a shot peening step of performing shot peening using a steel shot media having a Vickers hardness at least equal to 1100 and at most equal to 1300 and being free of boron, at least in a position on the shaft member, after the heat treatment step, to which the sensor portion is to be attached.

    DETECTION CIRCUIT AND DETECTION METHOD FOR MAGNETOSTRICTIVE TORQUE SENSOR

    公开(公告)号:US20210278296A1

    公开(公告)日:2021-09-09

    申请号:US17190138

    申请日:2021-03-02

    IPC分类号: G01L3/10

    摘要: A detection circuit for a magnetostrictive torque sensor is configured to detect a torque applied to a magnetostrictive material treated by shot peening. The detection circuit includes a detection coil provided around the magnetostrictive material, and a drive unit for providing alternating current excitation to the detection coil. The torque applied to the magnetostrictive material is detected based on a change in inductance of the detection coil, and the drive unit provides alternating current excitation at a frequency at which a skin effect thickness is not more than an effective depth of the shot peening.

    METHOD FOR MANUFACTURING MAGNETOSTRICTIVE TORQUE SENSOR SHAFT

    公开(公告)号:US20220074010A1

    公开(公告)日:2022-03-10

    申请号:US17416756

    申请日:2019-12-11

    申请人: NSK LTD.

    摘要: A method for manufacturing a magnetostrictive torque sensor shaft (100) to which a sensor portion (2) of a magnetostrictive torque sensor (1) is to be attached includes: a heat treatment step of subjecting an iron-based shaft member to a carburizing, quenching, and tempering process; a shot peening step of performing shot peening using a steel shot media having a Vickers hardness at least equal to 1100 and at most equal to 1300, at least in a position on the shaft member, after the heat treatment step, to which the sensor portion (2) is to be attached; and a surface polishing step of subjecting the shaft member after the shot peening to surface polishing.

    MAGNETOSTRICTIVE TORQUE SENSOR AND DESIGN METHOD OF THICKNESS OF MAGNETIC RING FOR MAGNETOSTRICTIVE TORQUE SENSOR

    公开(公告)号:US20220244118A1

    公开(公告)日:2022-08-04

    申请号:US17562469

    申请日:2021-12-27

    IPC分类号: G01L3/10

    摘要: A magnetostrictive torque sensor includes detection coils formed around a magnetostrictive material made of chrome steel or chrome molybdenum steel, a magnetic ring configured to cover around the detection coils, and a drive unit for providing alternating current excitation to the detection coils at an excitation frequency of 50 kHz or more and 333 kHz or less. A torque applied to the magnetostrictive material is detected based on a change in inductance of the detection coils. The magnetic ring is configured by wrapping around the detection coils with an amorphous tape made of amorphous soft magnetic material in a tape shape. The thickness of the magnetic ring is 1.455 times or more as thick as a skin effect thickness of the magnetostrictive material and less than 1.000 mm.