Position detection for rotary control valves

• US 6,484,751 B2
• Filed: 03/06/2001
• Issued: 11/26/2002
• Est. Priority Date: 02/23/1999
• Status: Expired due to Fees

• Current Assignee: DeZURIK Inc.
• Original Assignee: SPX Corporation
• Inventors: Cottles, Vernon M., DiEuliis, Val, Lafler, Lawrence R., Tanner, Douglas J.
• Primary Examiner(s): RIVELL, JOHN A
• Application Number:
  US09/799,043
• Publication Number:
  US 20010027812A1
• Time in Patent Office: 630 Days
• Field of Search: 137/554, 324/207.12, 324/207.2, 324/207.21, 324/207.25
• US Class Current: 137/554
• CPC Class Codes: F16K 37/0033 using a permanent magnet, e.g. in combination with a reed relays
• CPC Class Codes: F16K 37/0041 for measuring valve parameters F16K37/0033 takes precedence
• CPC Class Codes: G01D 5/145 influenced by the relative movement between the Hall device and magnetic fields see G01R33/06
• CPC Class Codes: Y10T 137/8242 Electrical

Abstract

A rotary control valve includes a flow control element having a lower valve shaft rotatably received in a non-magnetic body portion. A magnet is coupled with a lower valve shaft and rotatable therewith to produce an external magnetic field that varies in accordance with the angular position of the flow control element. A magnetic field detector, positioned in the external magnetic field, is operable to detect the external magnetic field and to produce position signals representative thereof, such being indicative of the angular position of the flow control element.

Claims

1. A valve comprising:

a valve body having walls defining a flow path therethrough;

a flow control element;

mounting structure coupled with said flow control element and rotatably mounting said element in said flow path for rotation therein through a plurality of angular positions, said mounting structure including a first valve shaft extending through said body and an opposed, second valve shaft rotatably received in a body portion with said body and

an angular position sensor including

at least one magnet fixed relative to the flow control element, the magnet being rotatable with the flow control element and operable to present a magnetic field,

a first sensor located so as to provide it with an angular orientation φ

₁ relative to a reference axis, and operable to detect the apparent strength of the magnetic field and to produce a signal V₁ which is indicative thereof;

a second sensor located so as to provide it with an angular orientation φ

₂ relative to the reference axis, and operable to detect the apparent strength of the magnetic field and to produce a signal V₂ which is indicative thereof;

an electric circuit operable to determine the angular position of the magnet and thereby the flow control element using the following formula, where the angular orientation of the rotatable element is θ

_v, $\begin{array}{cc}{\mathrm{\theta <br><br>}}_v=\arctan <br><br>\frac{\left[\cos <br><br>\text{\hspace{1em}<br><br>}<br><br>\left({\mathrm{\phi <br><br>}}_2\right)·<br><br>V_1-\cos <br><br>\text{\hspace{1em}<br><br>}<br><br>\left({\mathrm{\phi <br><br>}}_1\right)·<br><br>V_2\right]}{\left[\sin <br><br>\text{\hspace{1em}<br><br>}<br><br>\left({\mathrm{\phi <br><br>}}_1\right)·<br><br>V_2-\sin <br><br>\text{\hspace{1em}<br><br>}<br><br>\left({\mathrm{\phi <br><br>}}_2\right)·<br><br>V_1\right]}.& \left(16\right)\end{array}$

2. The valve of claim 1, the magnet being located inside of the of the valve body.

3. The valve of claim 1, the magnet being operable to present a magnetic field outside of the valve body and the first and second sensors being located outside of the valve body.

4. A valve comprising:

a valve body having walls defining a flow path therethrough;

a flow control element;

mounting structure coupled with said flow control element and rotatably mounting said element in said flow path for rotation therein through a plurality of angular positions, said mounting structure including a first valve shaft extending through said body and an opposed, second valve shaft rotatably received in a body portion with said body and

an angular position sensor;

wherein said angular position sensor includes two spaced magnets positioned within said second valve shaft, the north pole of one of said magnets being oriented adjacent the south pole and the other of said magnets, said magnets presenting respective first ends positioned adjacent said body portion and respective second ends inboard thereof, said sensor includes a ferromagnetic strap magnetically coupling said second ends.

5. The valve of claim 4, said angular position sensor includes two magnetic field detectors, each being subject to changes in sensitivity due to temperature, said sensors being positioned with respective angular orientations offset from one another sufficiently to reduce the effect of temperature changes on sensor accuracy.

6. A valve comprising:

a valve body having walls defining a flow path therethrough;

a flow control element;

mounting structure coupled with said flow control element and rotatably mounting said element in said flow path for rotation therein through a plurality of angular positions, said mounting structure including a first valve shaft extending through said body and an opposed, second valve shaft rotatably received in a body portion;

an angular position sensor;

wherein said angular position sensor includes two spaced magnets positioned within said second valve shaft, the north pole of one of said magnets being oriented adjacent the south pole and the other of said magnets, said magnets presenting respective first ends positioned adjacent said body portion and respective second ends inboard thereof, said sensor includes a ferromagnetic strap magnetically coupling said second ends,

said angular position sensor includes two magnetic field detectors, each being subject to changes in sensitivity due to temperature, said sensors being positioned with respective angular orientations offset from one another sufficiently to reduce the effect of temperature changes on sensor accuracy,

said magnetic field detectors are operable to produce position signals as respective voltage signals V₁ and V₂, said angular position of said flow control elements being represented by $\begin{array}{cc}{\mathrm{\theta <br><br>}}_v=\arctan <br><br>\frac{\left[\cos <br><br>\text{\hspace{1em}<br><br>}<br><br>\left({\mathrm{\phi <br><br>}}_2\right)·<br><br>V_1-\cos <br><br>\text{\hspace{1em}<br><br>}<br><br>\left({\mathrm{\phi <br><br>}}_1\right)·<br><br>V_2\right]}{\left[\sin <br><br>\text{\hspace{1em}<br><br>}<br><br>\left({\mathrm{\phi <br><br>}}_1\right)·<br><br>V_2-\sin <br><br>\text{\hspace{1em}<br><br>}<br><br>\left({\mathrm{\phi <br><br>}}_2\right)·<br><br>V_1\right]}.& \left(16\right)\end{array}$

where φ

₁ and φ

₂ are the respective angular orientations of said detectors.

7. An angular position sensor comprising:

at least one magnet fixed relative to a rotatable element, the magnet being rotatable with the element and operable to present a magnetic field,

a first sensor located so as to provide it with an angular orientation φ

₁ relative to a reference axis, and operable to detect the apparent strength of the magnetic field and to produce a signal V₁ which is indicative thereof;

a second sensor located so as to provide it with an angular orientation φ

₂ relative to the reference axis, and operable to detect the apparent strength of the magnetic field and to produce a signal V₂ which is indicative thereof;

an electric circuit operable to determine the angular position of the magnet and thereby the element using the following formula, where the angular orientation of the rotatable element is θ

_v, $\begin{array}{cc}{\mathrm{\theta <br><br>}}_v=\arctan <br><br>\frac{\left[\cos <br><br>\text{\hspace{1em}<br><br>}<br><br>\left({\mathrm{\phi <br><br>}}_2\right)·<br><br>V_1-\cos <br><br>\text{\hspace{1em}<br><br>}<br><br>\left({\mathrm{\phi <br><br>}}_1\right)·<br><br>V_2\right]}{\left[\sin <br><br>\text{\hspace{1em}<br><br>}<br><br>\left({\mathrm{\phi <br><br>}}_1\right)·<br><br>V_2-\sin <br><br>\text{\hspace{1em}<br><br>}<br><br>\left({\mathrm{\phi <br><br>}}_2\right)·<br><br>V_1\right]}.& \left(16\right)\end{array}$

8. An angular position sensor for sensing the position of a rotating first body in a second body, comprising:

two spaced magnets positioned within said first body, the north pole of one of said magnets being oriented adjacent the south pole and the other of said magnets, said magnets presenting respective first ends positioned adjacent said second body and respective second ends inboard thereof; and

a ferromagnetic strap magnetically coupling said second ends.

9. An angular position sensor for sensing the position of a rotating first body in a second body, comprising:

two spaced magnets positioned within said first body, the north pole of one of said magnets being oriented adjacent the south pole and the other of said magnets, said magnets presenting respective first ends positioned adjacent said second body and respective second ends inboard thereof;

a ferromagnetic strap magnetically coupling said second ends; and

two magnetic field detectors, each being subject to changes in sensitivity due to temperature, said sensors being positioned with respective angular orientations offset from one another sufficiently to reduce the effect of temperature changes on sensor accuracy.

10. The angular position sensor of claim 9, further including position signals as respective voltage signals V₁ and V₂, said angular position of said flow control elements being represented by $\begin{array}{c}{\theta }_{}\end{array}$

v=arctan

[cos

 



(φ

2)·

V1-cos

 



(φ

1)·

V2][sin

 



(φ

1)·

V2-sin

 



(φ

2)·

V1](16)

where φ

₁ and φ

₂ are the respective angular orientations of said detectors.

11. The angular position sensor of claim 10, wherein the rotatable element is a control element.

12. A valve comprising:

a valve body having walls defining a flow path therethrough;

a flow control element;

a mounting structure coupled with said flow control element and rotatably mounting said element in said flow path for rotation therein through a plurality of angular positions, said mounting structure including a first portion extending through said body and externally beyond the walls and a second portion rotatably received in a body portion within said body without projecting externally beyond the walls; and

an angular position sensor including

at least one magnet coupled with said second portion and rotatable therewith, said magnet being configured and positioned to present an external magnetic field at a location outside said valve body and adjacent said body portion, the apparent strength of said external magnetic field at said location being correlated with the angular position of said second valve portion and thereby with said flow control element, and

a magnetic field detector positioned in said external magnetic field at said location, operable to detect the strength of said external magnetic field, and operable to produce angular position signals representative thereof, such being indicative of the angular position of said flow control element.

13. A valve comprising:

a valve body having walls defining a flow path therethrough;

a flow control element;

a mounting structure coupled with said flow control element and rotatably mounting said element in said flow path for rotation therein through a plurality of angular positions, said mounting structure including a shaft, said shaft having a first portion extending through said body and externally beyond the walls and said shaft having a second portion rotatably received in a body portion within said body without projecting externally beyond the walls; and

an angular position sensor including

at least one magnet coupled with said second portion and rotatable therewith, said magnet being configured and positioned to present an external magnetic field at a location outside said valve body and adjacent said body portion, the apparent strength of said external magnetic field at said location being correlated with the angular position of said second portion and thereby with said flow control element, and

a magnetic field detector positioned in said external magnetic field at said location, operable to detect the strength of said external magnetic field, and operable to produce angular position signals representative thereof, such being indicative of the angular position of said flow control element.

14. A valve comprising:

a valve body having walls defining a flow path therethrough;

a flow control element;

mounting structure coupled with said flow control element and rotatably mounting said element in said flow path for rotation therein through a plurality of angular positions, said mounting structure including a first portion extending through said body and externally beyond the walls and a second portion rotatably received in a body portion within said body without projecting externally beyond the walls; and

an angular position sensor including

at least one magnet coupled with said second portion and rotatable therewith, said magnet being configured and positioned to present an external magnetic field at a location outside said valve body and adjacent said body portion, the apparent strength of said external magnetic field at said location being correlated with the angular position of said second portion and thereby with said flow control element, and

magnetic field detector positioned in said external magnetic field at said location, operable to detect the strength of said external magnetic field, and operable to produce angular position signals representative thereof, such being indicative of the angular position of said flow control element,

said angular position sensor including two spaced magnets positioned within said second portion,

the north pole of one of said magnets being oriented adjacent the south pole and the other of said magnets, said magnets presenting respective first ends positioned adjacent said body portion and respective second ends inboard thereof.

15. The valve according to claim 14, wherein said sensor includes a ferromagnetic strap magnetically coupling said second ends.

16. A valve comprising:

a valve body having walls defining a flow path therethrough;

a flow control element;

mounting structure coupled with said flow control element and rotatably mounting said element in said flow path for rotation therein through a plurality of angular positions, said mounting structure including a shaft having a first portion extending through said body and externally beyond the walls and said shaft having a second portion rotatably received in a body portion within said body without projecting externally beyond the walls; and

an angular position sensor including

at least one magnet coupled with said second portion and rotatable therewith, said magnet being configured and positioned to present an external magnetic field at a location outside said valve body and adjacent said body portion, the apparent strength of said external magnetic field at said location being correlated with the angular position of said second portion and thereby with said flow control element, and

magnetic field detector positioned in said external magnetic field at said location, operable to detect the strength of said external magnetic field, and operable to produce angular position signals representative thereof, such being indicative of the angular position of said flow control element,

said angular position sensor including two spaced magnets positioned within said second portion,

the north pole of one of said magnets being oriented adjacent the south pole and the other of said magnets, said magnets presenting respective first ends positioned adjacent said body portion and respective second ends inboard thereof.

17. The valve according to claim 16, wherein said sensor includes a ferromagnetic strap magnetically coupling said second ends.

18. A valve comprising:

a valve body having walls defining a flow path therethrough;

a flow control element;

a mounting structure coupled with said flow control element and rotatably mounting said element in said flow path for rotation therein through a plurality of angular positions; and

an angular position sensor including

at least one magnet fixed relative to the flow control element, the magnet being rotatable with the flow control element and operable to present a magnetic field,

a first sensor located so as to provide it with an angular orientation φ

₁ relative to a reference axis, and operable to detect the apparent strength of the magnetic field and to produce a signal V₁ which is indicative thereof;

a second sensor located so as to provide it with an angular orientation φ

₂ relative to the reference axis, and operable to detect the apparent strength of the magnetic field and to produce a signal V₂ which is indicative thereof;

an electric circuit operable to determine the angular position of the magnet and thereby the flow control element using the following formula, where the angular orientation of the rotatable element is θ

_v, $\begin{array}{cc}{\mathrm{\theta <br><br>}}_v=\arctan <br><br>\frac{\left[\cos <br><br>\text{\hspace{1em}<br><br>}<br><br>\left({\mathrm{\phi <br><br>}}_2\right)·<br><br>V_1-\cos <br><br>\text{\hspace{1em}<br><br>}<br><br>\left({\mathrm{\phi <br><br>}}_1\right)·<br><br>V_2\right]}{\left[\sin <br><br>\text{\hspace{1em}<br><br>}<br><br>\left({\mathrm{\phi <br><br>}}_1\right)·<br><br>V_2-\sin <br><br>\text{\hspace{1em}<br><br>}<br><br>\left({\mathrm{\phi <br><br>}}_2\right)·<br><br>V_1\right]}.& \left(16\right)\end{array}$

19. A valve comprising:

a valve body having walls defining a flow path therethrough;

a flow control element;

mounting structure coupled with said flow control element and rotatably mounting said element in said flow path for rotation therein through a plurality of angular positions, said mounting structure including a first valve shaft extending through said body and an opposed, second valve shaft rotatably received in a body portion; and

an angular position sensor;

wherein said angular position sensor includes two spaced magnets positioned within said second valve shaft, the north pole of one of said magnets being oriented adjacent the south pole of the other of said magnets, said magnets presenting respective first ends positioned adjacent said body portion and respective second ends inboard thereof.

20. The valve according to claim 19, wherein said sensor includes a ferromagnetic strap magnetically coupling said second ends.

21. A valve comprising:

a valve body having walls defining a flow path therethrough;

a flow control element;

mounting structure coupled with said flow control element and rotatably mounting said element in said flow path for rotation therein through a plurality of angular positions, said mounting structure including a first valve shaft extending through said body and an opposed, second valve shaft rotatably received in a body portion;

an angular position sensor;

wherein said angular position sensor includes two spaced magnets positioned within said second valve shaft, the north pole of one of said magnets being oriented adjacent the south pole and the other of said magnets, said magnets presenting respective first ends positioned adjacent said body portion and respective second ends inboard thereof, said sensor includes a ferromagnetic strap magnetically coupling said second ends,

said angular position sensor includes two magnetic field detectors, said detectors being positioned with respective angular orientations offset from one another.