Position determination for valves

Patent metadata

Field	Value
Publication number	US-11713984-B2
Application number	US-201916713085-A
Country	US
Kind code	B2
Filing date	Dec 13, 2019
Priority date	Aug 19, 2019
Publication date	Aug 1, 2023
Grant date	Aug 1, 2023

Abstract

A rotary encoder for a valve comprises a rotatable code plate and an optical detector module comprising one or more optical detectors. The code plate defines a set of voids arranged along a set of one or more concentric circular arcs about an axis of rotation. The voids define an angle-dependent pattern over the set of arcs, the pattern comprising a plurality of distinct sectoral elements (A-O, X). At least two of the sectoral elements, located in non-adjacent sectors of the code plate, are identical, but the pattern is non-repeating over a single full rotation of the code plate about the axis. Each optical detector is aligned with a respective concentric circular arc of the code plate. A controller processes time-varying output signals from the optical detectors to determine successive positions of the rotatable code plate.

First claim

The invention claimed is:

1. A position sensor for a valve, the position sensor comprising:
a rotary encoder; and
a controller;
wherein the rotary encoder comprises:
a rotatable code plate for coupling to a valve; and
an optical detector module comprising one or more optical detectors, wherein each optical detector is aligned with a respective concentric circular arc around the rotatable code plate and is configured to receive light passing through in the code plate when the code plate is in any of a first set of angular positions and to be blocked by the code plate from receiving light through the code plate when the code plate is in any of a second set of angular positions,

wherein the controller comprises:
a memory; and
control logic, wherein the control logic is configured, when in a first state, to:
receive a first set of time-varying output signals from the optical detector module as the code plate rotates during a first time period;
process the first set of time-varying output signals to determine, from the first set of time-varying output signals, a first position of the rotatable code plate; and
store data representative of the first position of the rotatable code plate in the memory, and

wherein the control logic is configured, when in a second state, to:
receive a second set of time-varying output signals from the optical detector module as the code plate rotates during a second time period, after the first time period; and
process i) the stored data representative of the first position of the rotatable code plate and ii) the second set of time-varying output signals, to determine, from the stored data and from the second set of time-varying output signals, a second position of the rotatable code plate

wherein the control logic is further configured to:
determine the first position from a predetermined set of positions, each corresponding to a respective range of angles of the code plate relative to the optical detector module;
determine the first position by comparing one or more time series of values from the first set of output signals with stored data representing a set of different possible positions for the code plate, to identify a match between the one or more time series of values and the stored data; and
use a timer to perform a time-aware comparison of said one or more time series of values against the stored data.

2. A position sensor as claimed in claim 1 , wherein the rotatable code plate is configured for rotation about an axis and defines a set of voids that the light passes through and that are arranged along a set of one or more concentric circular arcs about the axis,
wherein the voids define an angle-dependent pattern over the set of arcs, the pattern comprising a plurality of distinct sectoral elements,
wherein at least two of the sectoral elements, located in non-adjacent sectors of the code plate, are identical, wherein the pattern is non-repeating over a single full rotation of the code plate about the axis.

3. A position sensor as claimed in claim 2 , wherein the control logic is configured to enter the first state when the control logic is powered on or reset, and is configured to enter the second state after storing the data representative of the first position in the memory.

4. A position sensor as claimed in claim 3 , wherein each of the first and second sets of time-varying output signals comprises one or more sequences of values, each sequence of values depending on the output of a respective optical detector of the optical detector module, and each value being representative of whether or not the respective optical detector is receiving light passing through the plane of the code plate at a respective moment in time, wherein at least one of the sequences of values in each of the first and second sets of time-varying output signals comprises at least two different values, each value corresponding to a different moment in time.

5. A position sensor for a valve, the position sensor comprising:
a rotary encoder; and
a controller;
wherein the rotary encoder comprises:
a rotatable code plate for coupling to a valve; and
an optical detector module comprising one or more optical detectors, wherein each optical detector is aligned with a respective concentric circular arc around the rotatable code plate and is configured to receive light passing through the code plate when the code plate is in any of a first set of angular positions and to be blocked by the code plate from receiving light through the code plate when the code plate is in any of a second set of angular positions,

wherein the controller comprises:
a memory; and
control logic, wherein the control logic is configured, when in a first state, to:
receive a first set of time-varying output signals from the optical detector module as the code plate rotates during a first time period;
process the first set of time-varying output signals to determine, from the first set of time-varying output signals, a first position of the rotatable code plate; and
store data representative of the first position of the rotatable code plate in the memory, and

wherein the control logic is configured, when in a second state, to:
receive a second set of time-varying output signals from the optical detector module as the code plate rotates during a second time period, after the first time period; and
process i) the stored data representative of the first position of the rotatable code plate and ii) the second set of time-varying output signals, to determine, from the stored data and from the second set of time-varying output signals, a second position of the rotatable code plate;

wherein the control logic is configured, when in the second state, to maintain a value in the memory representative of a current position of the code plate, and is configured to detect changes in the second set of output signals and to advance the stored current position by one increment around a cycle of position values in response to each change of state in the second set of time-varying output signals.

6. A position sensor as claimed in claim 5 , wherein the rotatable code plate is configured for rotation about an axis and defines a set of voids that the light passes through and that are arranged along a set of one or more concentric circular arcs about the axis,
wherein the voids define an angle-dependent pattern over the set of arcs, the pattern comprising a plurality of distinct sectoral elements,
wherein at least two of the sectoral elements, located in non-adjacent sectors of the code plate, are identical, wherein the pattern is non-repeating over a single full rotation of the code plate about the axis.

7. A position sensor as claimed in claim 6 , wherein the control logic is configured to enter the first state when the control logic is powered on or reset, and is configured to enter the second state after storing the data representative of the first position in the memory.

8. A position sensor as claimed in claim 7 , wherein each of the first and second sets of time-varying output signals comprises one or more sequences of values, each sequence of values depending on the output of a respective optical detector of the optical detector module, and each value being representative of whether or not the respective optical detector is receiving light passing through the plane of the code plate at a respective moment in time, wherein at least one of the sequences of values in each of the first and second sets of time-varying output signals comprises at least two different values, each value corresponding to a different moment in time.

9. A position sensor for a valve, the position sensor comprising:
a rotary encoder; and
a controller;
wh

Assignees

• Goodrich Corp

Inventors

• Sapija Dariusz
• Niewodniczański Mikolaj
• Grzybowski Jerzy Jakub

Classifications

• G01D5/34707 Primary

  Scales; Discs, e.g. fixation, fabrication, compensation · CPC title

• F16K37/0058

  Optical means, e.g. light transmission, observation ports (F16K37/0075 takes precedence) · CPC title

• G01D5/3473 Primary

  Circular or rotary encoders · CPC title

• G01D5/34738

  Axles; Driving or coupling means · CPC title

• G01D5/34792

  with only digital scales or both digital and incremental scales · CPC title