Torque sensor

Patent metadata

Field	Value
Publication number	US-2016305833-A1
Application number	US-201615088344-A
Country	US
Kind code	A1
Filing date	Apr 1, 2016
Priority date	Apr 14, 2015
Publication date	Oct 20, 2016
Grant date	—

Abstract

A torque sensor for being attached around a magnetostrictive rotating shaft includes a bobbin that is provided coaxially with the rotating shaft, wherein the bobbin includes a resin, a hollow cylindrical shape, and first inclined grooves and second inclined grooves formed on an outer peripheral surface thereof, wherein the first inclined grooves are inclined at a predetermined angle relative to an axial direction, and wherein the second inclined grooves are inclined at a predetermined angle relative to the axial direction in an opposite direction of the first inclined grooves, a first detection coil including an insulated wire wound around the bobbin along the first inclined grooves, a second detection coil including the insulated wire wound around the bobbin along the second inclined grooves, and a measurement portion that detects a inductance variation of the first and second detection coils so as to measure a torque applied to the rotating shaft.

First claim

What is claimed is:

1 . A torque sensor for being attached around a magnetostrictive rotating shaft, comprising:
a bobbin that is provided coaxially with and at a distance from the rotating shaft, wherein the bobbin comprises a resin, a hollow cylindrical shape, and a plurality of first inclined grooves and a plurality of second inclined grooves formed on an outer peripheral surface thereof, wherein the first inclined grooves are inclined at a predetermined angle relative to an axial direction, and wherein the second inclined grooves are inclined at a predetermined angle relative to the axial direction in an opposite direction of the first inclined grooves; a first detection coil comprising an insulated wire wound around the bobbin along the first inclined grooves; a second detection coil comprising the insulated wire wound around the bobbin along the second inclined grooves; and a measurement portion that detects a inductance variation of the first and second detection coils so as to measure a torque applied to the rotating shaft.

2 . The torque sensor according to claim 1 , wherein the first inclined grooves are inclined at +45 degrees relative to the axial direction, and
wherein the second inclined grooves are inclined at −45 degrees relative to the axial direction.

3 . The torque sensor according to claim 1 , further comprising a magnetic ring comprising a hollow cylindrical magnetic material around the bobbin.

4 . The torque sensor according to claim 1 , wherein the bobbin comprises a polyphthalamide resin, a polyether ether ketone resin or a polyphenylene sulfide resin.

Assignees

• Hitachi Metals Ltd

Inventors

• Nakamura Teruyuki

Classifications

• G01L3/105

  involving inductive means (G01L3/102, G01L3/104 take precedence) · CPC title

• G01L3/102 Primary

  involving magnetostrictive means (magnetostrictive sensors H10N35/101) · CPC title

• Y10T29/4902

  Electromagnet, transformer or inductor · CPC title

• G01L3/103 Primary

  Details about the magnetic material used · CPC title

• G01R3/00

  Apparatus or processes specially adapted for the manufacture {or maintenance} of measuring instruments {, e.g. of probe tips} · CPC title