Variable differential transformer position sensor with a trapezoidal primary coil

Patent metadata

Field	Value
Publication number	US-2016334245-A1
Application number	US-201514806075-A
Country	US
Kind code	A1
Filing date	Jul 22, 2015
Priority date	May 14, 2015
Publication date	Nov 17, 2016
Grant date	—

Abstract

A transformer includes a bobbin, a primary coil, and a pair of secondary coils. The bobbin has an axial bore formed therein. The primary coil is wound on the bobbin and is adapted to be electrically excited with an excitation signal. The secondary coils are disposed adjacent to the primary coil, and are inductively coupled to the primary coil upon electrical excitation of the primary coil. The primary coil is wound on the bobbin such that at least a portion of the primary coil has a cross section shape that is a trapezoid.

First claim

What is claimed is:

1 . A transformer, comprising:
a bobbin having an axial bore formed therein; a primary coil wound on the bobbin and adapted to be electrically excited with an excitation signal; and a pair of secondary coils disposed adjacent to the primary coil, the secondary coils inductively coupled to the primary coil upon electrical excitation of the primary coil, wherein the primary coil is wound on the bobbin such that at least a portion of the primary coil has a cross section shape that is a trapezoid.

2 . The transformer of claim 1 , wherein each secondary coil has a cross section shape that is a triangle.

3 . The transformer of claim 1 , wherein the trapezoid is an isosceles trapezoid.

4 . The transformer of claim 3 , wherein each secondary coil has a cross section shape that is a right triangle.

5 . The transformer of claim 1 , wherein:
the trapezoid has two parallel sides and two non-parallel sides; each of the secondary coils is wound around a different one of the non-parallel sides.

6 . The transformer of claim 5 , wherein each secondary coil has a cross section shape that is a triangle.

7 . The transformer of claim 5 , wherein the trapezoid is an isosceles trapezoid.

8 . The transformer of claim 7 , wherein each secondary coil has a cross section shape that is a right triangle.

9 . The transformer of claim 1 , wherein the primary coil is wound on the bobbin such that:
a first portion of the primary coil has a cross section shape that is a rectangle; and a second portion of the primary coil has a cross section shape that is a trapezoid.

10 . A linear variable differential transformer position sensor, comprising:
a bobbin having an axial bore formed therein; a core movably disposed within the axial bore; a primary coil wound on the bobbin and adapted to be electrically excited with an excitation signal; and a pair of differentially wound secondary coils disposed adjacent to the primary coil, each secondary coil inductively coupled to the primary coil upon electrical excitation of the primary coil, wherein the primary coil is wound on the bobbin such that at least a portion of the primary coil has a cross section shape that is a trapezoid.

11 . The linear variable differential transformer position sensor of claim 10 , wherein each secondary coil has a cross section shape that is a triangle.

12 . The linear variable differential transformer position sensor of claim 10 , wherein the trapezoid is an isosceles trapezoid.

13 . The linear variable differential transformer position sensor of claim 11 , wherein each secondary coil has a cross section shape that is a right triangle.

14 . The linear variable differential transformer position sensor of claim 10 , wherein:
the trapezoid has two parallel sides and two non-parallel sides; each of the secondary coils is wound around a different one of the non-parallel sides.

15 . The linear variable differential transformer position sensor of claim 14 , wherein each secondary coil has a cross section shape that is a triangle.

16 . The linear variable differential transformer position sensor of claim 14 , wherein the trapezoid is an isosceles trapezoid.

17 . The linear variable differential transformer position sensor of claim 16 , wherein each secondary coil has a cross section shape that is a right triangle.

18 . The transformer of claim 10 , wherein the primary coil is wound on the bobbin such that:
a first portion of the primary coil has a cross section shape that is a rectangle; and a second portion of the primary coil has a cross section shape that is a trapezoid.

19 . A linear variable differential transformer position sensor, comprising:
a bobbin having an axial bore formed therein; a core movably disposed within the axial bore; a primary coil wound on the bobbin and adapted to be electrically excited with an excitation signal; a pair of differentially wound secondary coils disposed adjacent to the primary coil, each secondary coil inductively coupled to the primary coil upon electrical excitation of the primary coil; and a housing surrounding at least portions of the bobbin, the core, the primary coil, and the secondary coils, wherein:
the primary coil is wound on the bobbin such that the primary coil has a cross section shape that is an isosceles trapezoid, and
each secondary coil has a cross section shape that is a right triangle.

20 . The linear variable differential transformer position sensor of claim 19 , wherein:
the trapezoid has two parallel sides and two non-parallel sides; each of the secondary coils is wound around a different one of the non-parallel sides.

Assignees

• Honeywell Int Inc

Inventors

• Esakki Subramanian
• Sanchihar Paresh
• Araganji Vijayshekhar
• Narasimhan Kumaran Sena

Classifications

• H01F21/06

  by movement of core or part of core relative to the windings as a whole · CPC title

• G01D5/2291 Primary

  Linear or rotary variable differential transformers (LVDTs/RVDTs) having a single primary coil and two secondary coils · CPC title

• H01F27/2823

  Wires (H01F27/2866 takes precedence) · CPC title

• H01F27/24

  Magnetic cores · CPC title

• H01F27/325

  Coil bobbins (formers for coils in general H01F5/02) · CPC title