US 5,177,389 A · Tacho generator

Abstract

A servo controlled motor has an annular coil arrangement with meander-shaped windings and an annular arrangement of magnetic pole pairs, positioned for concentric relative rotation. A first coil is formed by a first number of the windings aligned at a first angle and with consistent pitch relative to a diameter line. A first number of pole pairs are aligned at the first angle and correspond in number and pitch to the first number of windings. A second coil is formed by a second number of windings. The second number of windings is aligned at a second angle relative to the diameter line. A second number of the pole pairs are aligned at the second angle and correspond in number and pitch to the second number of windings. Voltages are induced in the second coil by the second, but not by the first, number of pole pairs. Alternatively, the first number of windings define a grid of winding positions. A second coil is formed by a second number of windings aligned at the first angle. Some of the second number of windings are disposed in winding positions and others are offset from winding positions. A second number of the pole pairs aligned substantially at the first angle correspond in number and relative position to the second number of windings. Voltages induced in the second number of windings by the first number of pole pairs substantially cancel out, but voltages induced by the second number of pole pairs add together.

Claims26

Dependent claims

A tacho generator for a servo controlled motor, comprising:

an annular coil arrangement with first and second numbers of meander-shaped windings;
an annular arrangement of North-South magnetic pole pairs, said annular coil arrangement and said annular arrangement of North-South magnetic pole pairs being positioned for concentric rotation relative to one another;
a first coil formed by said first number of said meander-shaped windings aligned at a first angle and with consistent pitch relative to a diameter line of said annular coil arrangement;
a first number of said North-South magnetic pole pairs corresponding in number and pitch to said first number of said meander-shaped windings, said first number of said North-South magnetic pole pairs aligned at said first angle;
a second coil formed by said second number of said meander-shaped windings distributed over said annular coil arrangement, said second number of said meander-shaped windings aligned at a second angle relative to said diameter line;
and,
a second number of said North-South magnetic pole pairs corresponding in number and pitch to said second number of said meander-shaped windings and aligned at said second angle, voltages being induced in each winding of said second coil by said second number of North-South magnetic pole pairs, but not by said first number of North-South magnetic pole pairs, during said relative rotation.

4 more elements

A tacho generator for a servo controlled motor, comprising:

an annular coil arrangement with first and second numbers of meander-shaped windings;
an annular arrangement of North-South magnetic pole pairs, said annular coil arrangement and said annular arrangement of North-South magnetic pole pairs being positioned for concentric rotation relative to one another;
a first coil formed by said first number of said meander-shaped windings aligned at an angle relative to a diameter line of said annular coil arrangement and defining a grid of winding positions having consistent pitch;
a first number of said North-South magnetic pole pairs corresponding in number and pitch to said first number of said meander-shaped windings, said first number of said North-South magnetic pole pairs aligned substantially at said angle;
a second coil formed by said second number of said meander-shaped windings distributed over said annular coil arrangement, said second number of said meander-shaped windings aligned substantially at said angle, some of said second number of said meander-shaped windings disposed in respective ones of said winding positions and others of said second number of said meander-shaped windings disposed offset from said winding positions;
and,
a second number of said North-South magnetic pole pairs corresponding in number and relative position to said second number of said meander-shaped windings, said second number of North-South magnetic pole pairs aligned substantially at said angle.

4 more elements

Dependencies are inferred from the claim text.

Tacho generator

Life of this patent

Tacho generator

Life of this patent

Abstract

Claims26