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CN-121976992-A - Method for diagnosing, detecting and locating leaks in pneumatic systems

CN121976992ACN 121976992 ACN121976992 ACN 121976992ACN-121976992-A

Abstract

Methods of diagnosing and detecting and locating leaks in pneumatic systems are provided. The method includes the steps of pressurizing a first passage extending from a manifold through a valve to a first fitting, measuring a first pressure decay within the first passage based at least in part on a change in pressure within the first passage over a first period of time, pressurizing a second passage extending from the manifold through the valve to a second fitting, measuring a second pressure decay within the second passage based at least in part on a change in pressure within the second passage over a second period of time, comparing the first and second pressure decays to a limit threshold, determining that a leak exists between the manifold and the valve in response to determining that the first and second pressure decays are greater than the limit threshold, determining that a leak exists between the valve and the first fitting in response to determining that the first pressure decay is greater than the limit threshold and the second pressure decay is less than the limit threshold, and determining that a leak exists between the valve and the second fitting in response to determining that the first pressure decay is less than the limit threshold and the second pressure decay is greater than the limit threshold.

Inventors

  • Christopher Mandy
  • Robert torney
  • Dana Noel
  • Nicholas Schrag

Assignees

  • 贝克曼库尔特有限公司

Dates

Publication Date
20260505
Application Date
20191226
Priority Date
20181228

Claims (11)

  1. 1. A method (201,401,501) of diagnosing a leak in a pneumatic system (5) of a laboratory instrument (3), the method comprising: (a) Pressurizing a first passage, wherein the first passage extends from a manifold (47) through a valve (63,65,67,81,103,105,107) to a first fitting (110, 112, 114); (b) Measuring a first pressure decay within the first passage, wherein the first pressure decay is based at least in part on a change in pressure within the first passage over a first period of time; (c) Pressurizing a second passage, wherein the second passage extends from the manifold (47) through the valve (63,65,67,81,103,105,107) to a second fitting (110, 112, 114); (d) Measuring a second pressure decay within the second channel, wherein the second pressure decay is based at least in part on a change in pressure within the second channel over a second period of time; (e) Comparing the first pressure decay and the second pressure decay to a limit threshold; (f) Responsive to determining that the first pressure decay and the second pressure decay are greater than the limit threshold, determining that a leak exists between the manifold (47) and the valve (63,65,67,81,103,105,107); (g) In response to determining that the first pressure decay is greater than the limit threshold and the second pressure decay is less than the limit threshold, determining that a leak exists between the valve (63,65,67,81,103,105,107) and the first fitting (110, 112, 114), and (H) In response to determining that the first pressure decay is less than the limit threshold and the second pressure decay is greater than the limit threshold, it is determined that a leak exists between the valve (63,65,67,81,103,105,107) and the second fitting (110, 112, 114).
  2. 2. The method (201,401,501) according to claim 1, wherein the valve (63,65,67,81,103,105,107) includes a three-way valve (81,103,105,107).
  3. 3. The method (201,401,501) according to claim 1 or 2, further comprising providing a gas cylinder (79) between the first fitting (110, 112, 114) and the second fitting (110, 112, 114).
  4. 4. The method (201,401,501) according to claim 3, further comprising: (a) Driving the cylinder (79) to a first position in response to pressurizing the first passage, and (B) The cylinder (79) is driven to a second position in response to pressurizing the second passage.
  5. 5. The method (201,401,501) according to any one of claims 1 to 4, further comprising storing the first pressure decay and the second pressure decay in a computer memory (30) of the laboratory instrument (3).
  6. 6. The method (201,401,501) according to any one of claims 1 to 5, further comprising storing the first pressure decay and the second pressure decay in a memory (30) of a computer system (9), wherein the computer system (9) is remote from the laboratory instrument (3).
  7. 7. The method (201,401,501) according to any one of claims 1 to 6, wherein the method of diagnosing a leak is initiated automatically at periodic intervals.
  8. 8. The method (201,401,501) according to any one of claims 1 to 7, wherein measuring the first pressure decay includes: (a) Measuring a first pressure within the first passage; (b) Waiting for the first period of time; (c) Measuring a second pressure in the first passage, and (D) The first pressure decay is calculated as a difference between the first pressure and the second pressure.
  9. 9. The method (201,401,501) according to claim 8, wherein measuring the second pressure decay includes: (a) Measuring a third pressure within the second passage; (b) Waiting for the second period of time; (c) Measuring a fourth pressure in the second passage, and (D) The second pressure decay is calculated as the difference between the third pressure and the fourth pressure.
  10. 10. The method (201,401,501) of any one of claims 1 to 9, further comprising generating an alert in response to determining that a leak exists between the manifold (47) and the valve (63,65,67,81,103,105,107).
  11. 11. A method (201,401,501) of detecting and locating leaks in a pneumatic system (5), comprising: (a) Pneumatically associating a sensor (89) with a branch (85) of the pneumatic system (5), wherein the branch (85) comprises at least two three-way four-port valves (103, 105, 107), wherein each valve (103, 105, 107) is pneumatically associated with a pneumatic component (91,93,95), wherein each pneumatic component (91,93,95) is pneumatically drivable to switch between a first state and a second state; (b) Iteratively pneumatically driving each pneumatic component (91,93,95) in the branch (85) to pressurize a plurality of channels within the branch (85); (c) Measuring pressure in a channel of the plurality of channels with the sensor (89) over a period of time to determine pressure decay in response to pressurizing the channel, and (D) A location of a leak within the branch (85) is determined, wherein the determination is based at least in part on the measured pressure decay.

Description

Method for diagnosing, detecting and locating leaks in pneumatic systems The application is a divisional application of the application patent application with the application date of 2019, 12-month 26, the application number of 201980086982.1 (International phase application number of PCT/US 2019/068583) and the application name of 'pneumatic system with advanced system diagnosis capability'. Cross Reference to Related Applications The present application is related to and claims the provisional patent application 62/785,850 entitled "Pneumatics SYSTEM WITH ADVANCED SYSTEM Diagnostics Capabilities" filed in the U.S. patent office at 12/28 of 2018. The provisional patent application is incorporated herein by reference in its entirety. Background Pneumatic system leaks or leak faults have been difficult to diagnose and repair in the field in the past. In many cases, the field service engineer does not detect the leak and while the leak may not result in an error on the primary subsystem, it may result in a secondary problem on the relevant subsystem, making diagnosis even more difficult. Proper diagnostics require extensive skill of the field service engineer and detailed knowledge of the pneumatic system to accurately locate the leak. Trial and error is a method used by sub-branching isolation, which is time consuming and does not always produce correct results. Accordingly, there is a need for a method or system that enables a pneumatic system to self-diagnose and accurately locate the area within the pneumatic system where the leak is located. Disclosure of Invention The present disclosure relates to a method of diagnosing leakage faults in a pneumatic system. In one exemplary method, a plurality of components that are to be serviced by a common branch of a pneumatic system are set to a first configuration using a plurality of respective valves. Thereafter, leakage of the plurality of components in the first configuration is measured in common. The plurality of components are then set into a second configuration using the plurality of respective valves, and leakage of the plurality of components in the second configuration is measured in common. If the measured leakage is less than the first configuration threshold when the plurality of components are in the first configuration and the measured leakage is less than the second configuration threshold when the plurality of components are in the second configuration, the method reports a pass result. In another exemplary method, the first passage is pressurized. In this example, the first passage extends from the manifold through the valve to the first fitting. Thereafter, a first pressure decay within the first passage is measured, wherein the first pressure decay is based at least in part on a change in pressure within the first passage over a first period of time. Thereafter, the second channel is pressurized. In this example, the second passage extends from the manifold through the valve to the second fitting. Thereafter, a second pressure decay within the second passage is measured, wherein the second pressure decay is based at least in part on a change in pressure within the second passage over a second period of time. After measuring the two pressure decays, the first pressure decay and the second pressure decay are compared to a limiting threshold. In response to determining that the first pressure decay and the second pressure decay are greater than the limit threshold, the method determines that a leak exists between the manifold and the valve. In response to determining that the first pressure decay is greater than the limit threshold and the second pressure decay is less than the limit threshold, the method determines that a leak exists between the valve and the first fitting. In response to determining that the first pressure decay is less than the limit threshold and the second pressure decay is greater than the limit threshold, the method determines that a leak exists between the valve and the second fitting. In another exemplary method, the sensor is pneumatically associated with a branch of the pneumatic system. In this example, the branch includes at least two three-way four-port valves pneumatically associated with the pneumatic components, and each pneumatic component is pneumatically drivable to transition between a first state and a second state. Thereafter, each pneumatic component in the branch is pneumatically driven to pressurize a plurality of channels within the branch. In response to pressurizing a channel of the plurality of channels, the pressure in the channel is measured with a sensor over a period of time to determine a pressure decay. Thereafter, a location of the leak within the branch is determined, wherein the determination is based at least in part on the measured pressure decay. Drawings While the specification concludes with claims particularly pointing out and distinctly claiming the present invention, it is believed