Servovalve with adjustable air gaps

Patent metadata

Field	Value
Publication number	US-11018568-B2
Application number	US-201816208963-A
Country	US
Kind code	B2
Filing date	Dec 4, 2018
Priority date	Mar 8, 2018
Publication date	May 25, 2021
Grant date	May 25, 2021

Abstract

A torque motor for a servovalve is provided, the torque motor comprising an armature and a first pole piece. The first pole piece has a first portion and a second portion that is selectively moveable relative to the first portion such that a size of an air gap formed between the second portion and the armature is adjusted in response to the movement of the second portion relative to the first portion.

First claim

The invention claimed is:

1. A torque motor for a servovalve, said torque motor comprising:
an armature;
a first pole piece having a first portion and a second portion that is selectively moveable relative to the first portion such that a size of an air gap formed between the second portion and the armature is adjusted in response to the movement of the second portion relative to the first portion;
wherein the second portion includes first and second surfaces;
wherein a first surface of the armature and the second surface of the second portion between which the air gap is defined remain substantially parallel throughout a range of relative movement between the first portion and the second portion;
attachment means configured to attach the second portion to the first portion; and
retaining means secured onto the attachment means to secure the second portion to the first pole piece section.

2. The torque motor of claim 1 , wherein movement of the second portion relative to the first portion is in a direction parallel to the first surface.

3. The torque motor of claim 1 , wherein the attachment means is a screw and the retaining means is a nut.

4. The torque motor of claim 1 , wherein the first pole piece and the first portion further comprise:
an opening and the second portion further comprises an opening, and wherein the attachment means is provided through the opening in the first pole piece and the first portion, and the opening in the second portion.

5. The torque motor of claim 1 , wherein the opening in the first pole piece is a slot to provide an area for movement of the attachment means, and the opening in the second portion has the same diameter as the attachment means such that the attachment means is flush with the opening of the second portion.

6. A torque motor for a servovalve, said torque motor comprising:
an armature;
a first pole piece having a first portion and a second portion that is selectively moveable relative to the first portion such that a size of an air gap formed between the second portion and the armature is adjusted in response to the movement of the second portion relative to the first portion;
wherein the second portion includes first and second surfaces;
wherein a first surface of the armature and the second surface of the second portion between which the air gap is defined remain substantially parallel throughout a range of relative movement between the first portion and the second portion; and
a second pole piece;
wherein the armature is disposed between the first pole piece and the second pole piece;
wherein the first pole piece further comprises a first pole piece section with a ring shape extending in a plane, wherein the first portion extends perpendicularly away from the first pole piece section to an angled surface disposed at an angle relative to the plane;
wherein the first surface is disposed at the same angle as the angled surface and the second surface is substantially parallel to the plane; and wherein the first surface of the second portion is releasably coupled to the angled surface.

7. The torque motor of claim 6 , wherein the angled surfaces are disposed at an angle of between 5° and 25° to the plane.

8. A method of adjusting an air gap in a torque motor, the method comprising:
providing an armature;
providing a first pole piece having a first portion and a second portion;
selectively moving the second portion relative to the first portion such that a size of an air gap formed between the second portion and the armature is adjusted in response to the movement of the second portion relative to the first portion;
providing a second pole piece;
disposing the armature between the first pole piece and the second pole piece,
wherein the first pole piece further comprises a first pole piece section with a ring shape extending in a plane, wherein the first portion extends perpendicularly away from the first pole piece section to an angled surface disposed at an angle relative to the plane, and the second portion having a first surface disposed at the same angle as the angled surface and a second surface substantially parallel to the plane; and
releasably coupling the first surface of the second portion to the angled surface.

9. The method of claim 8 , wherein a first surface, the armature, and a second surface of the second portion between which the air gap is defined remain substantially parallel throughout a range of relative movement between the first portion and the second portion.

10. The method of any of claim 8 , further comprising moving the second portion relative to the first portion in a direction parallel to the first surface.

11. The method of any of claim 8 , wherein the angled surface is disposed at an angle of between 5° and 25° to the plane.

12. The method of claim 8 , further comprising providing attachment means to attach the second portion to the first portion.

13. The method of claim 12 , further comprising tightening a retaining means onto the attachment means for securing the second portion to the first portion.

14. The method of claim 13 , wherein the first pole piece section and first portion further comprise an opening and the second portion further comprises an opening, and the method further comprises:
providing the attachment means through the opening in the first pole piece section and the first portion, and the opening in the second portion, and wherein the opening in the first pole piece section and first section is a slot providing an area for movement of the attachment means.

15. The method of claim 14 , wherein the opening in the second portion has the same diameter as the attachment means such that the attachment means is flush with the opening of the second portion.

16. The method of claim 14 further comprising:
loosening the attachment means and the retaining means,
moving the second portion in a direction parallel to the plane, and therefore moving the attachment means within the opening to result in an adjustment of the air gap,
tightening the attachment means and the retaining means, thereby securing the second portion in position in relation to the first portion.

Assignees

• Hamilton Sundstrand Corp
• Hamilton Sunstrand Corp

Inventors

• Sawicki Piotr
• Cis Marcin

Classifications

• F15B13/0438 Primary

  the pilot valves being of the nozzle-flapper type · CPC title

• H02K2201/03

  Machines characterised by aspects of the air-gap between rotor and stator · CPC title

• H02K2213/09

  Machines characterised by the presence of elements which are subject to variation, e.g. adjustable bearings, reconfigurable windings, variable pitch ventilators · CPC title

• H02K15/062

  Windings in slots; Salient pole windings · CPC title

• H02K1/08

  Salient poles · CPC title