Magnetic chip detector

Patent metadata

Field	Value
Publication number	US-11448636-B2
Application number	US-202017036683-A
Country	US
Kind code	B2
Filing date	Sep 29, 2020
Priority date	Sep 29, 2020
Publication date	Sep 20, 2022
Grant date	Sep 20, 2022

Abstract

Magnetic chip detectors for detecting magnetic chips in a lubrication fluid are provided. The chip detector includes a first electric terminal, a second electric terminal and a magnet. The second electric terminal is spaced apart from the first electric terminal to define a gap between the first and second electric terminals. The gap exposes a cavity formed in the magnet for collecting magnetic chips. The cavity accommodates the accumulation of smaller and relatively harmless magnetic chips without triggering an alarm to reduce the occurrence of nuisance alarms.

First claim

What is claimed is:

1. A magnetic chip detector comprising:
a first electric terminal;
a second electric terminal spaced apart from the first electric terminal to define a gap therebetween, the gap having a width between the first and second electric terminals and a depth between a first side and a second side of the gap, the first side of the gap defining an opening for establishing fluid communication between the gap and an ambient environment; and
a magnet disposed outside of the gap and adjacent the second side of the gap, the magnet including a recess defining a cavity in fluid communication with the gap to collect one or more magnetic chips that have entered the gap via the opening.

2. The magnetic chip detector of claim 1 , wherein the gap and the cavity extend substantially completely around an axis.

3. The magnetic chip detector of claim 2 , wherein the first and second electric terminals are axially spaced apart relative to the axis.

4. The magnetic chip detector of claim 3 , wherein:
the cavity is in substantial axial alignment with the gap; and
the cavity is adjacent the gap.

5. The magnetic chip detector of claim 4 , wherein
a width of the cavity is substantially equal to the width of the gap.

6. The magnetic chip detector of claim 1 , wherein:
the first electric terminal defines a first receptacle in which a first portion of the magnet is received; and
the second electric terminal defines a second receptacle in which a second portion of the magnet is received.

7. The magnetic chip detector of claim 1 , wherein the cavity has a substantially U-shaped cross-sectional profile.

8. The magnetic chip detector of claim 1 , wherein the cavity is adjacent the second side of the gap.

9. The magnetic chip detector of claim 2 , wherein the first and second electric terminals are radially spaced apart relative to the axis.

10. The magnetic chip detector of claim 9 , wherein:
the cavity is in substantial radial alignment with the gap; and
the cavity is adjacent the gap.

11. The magnetic chip detector of claim 1 , wherein
a width of the cavity is substantially equal to the width of the gap.

12. An aircraft engine comprising:
a lubrication system for distributing lubrication fluid to one or more lubrication loads; and
a magnetic chip detector immersed in the lubrication fluid, the magnetic chip detector comprising:
a first electric terminal;
a second electric terminal spaced apart from the first electric terminal to define a gap therebetween, the gap having a width between the first and second electric terminals and a depth between a first side and a second side of the gap, the first side of the gap defining an opening for establishing fluid communication between the gap and an ambient environment; and
a magnet disposed outside of the gap, the magnet including a cavity formed therein, the cavity being disposed adjacent the second side of the gap and in fluid communication with the gap via the second side of the gap.

13. The aircraft engine of claim 12 , wherein the gap and the cavity extend substantially completely around an axis.

14. The aircraft engine of claim 13 , wherein the first and second electric terminals are axially spaced apart relative to the axis.

15. The magnetic chip detector of claim 13 , wherein the first and second electric terminals are radially spaced apart relative to the axis.

16. The magnetic chip detector of claim 12 , wherein a width of the cavity is substantially equal to the width of the gap.

17. A method of detecting one or more magnetic chips in a lubrication fluid of an engine using a magnetic chip detector including: a first electric terminal and a second electric terminal defining a gap therebetween; and a magnet including a magnet cavity adjacent the gap, the method comprising:
receiving the lubrication fluid in the gap and in the magnet cavity;
collecting one or more first magnetic chips inside the magnet cavity without generating a magnetic chip detection signal;
collecting one or more second magnetic chips at the magnetic chip detector; and
after collecting the one or more second magnetic chips at the magnetic chip detector, generating the magnetic chip detection signal.

18. The method of claim 17 , comprising collecting the one or more second magnetic chips inside the gap.

19. The method of claim 17 , comprising collecting the one or more second magnetic chips outside the gap.

20. The method of claim 17 , wherein the one or more first magnetic chips are smaller than the one or more second magnetic chips.

Assignees

• Pratt & Whitney Canada

Inventors

• Padilla Martinez Alan
• Castonguay Pierre
• Caron-Saint-Georges Hubert

Classifications

• F01M11/10

  Indicating devices; Other safety devices · CPC title

• G01N2015/0053

  in liquids, e.g. trouble · CPC title

• F16N2200/04

  Detecting debris, chips, swarfs · CPC title

• F01D25/18

  Lubricating arrangements (of machines or engines in general F01M) · CPC title

• F16N2250/52

  magnetic · CPC title