Systems and methods for detecting damage in a positive crankcase ventilation tube

Patent metadata

Field	Value
Publication number	US-9828950-B2
Application number	US-201514865437-A
Country	US
Kind code	B2
Filing date	Sep 25, 2015
Priority date	Sep 25, 2015
Publication date	Nov 28, 2017
Grant date	Nov 28, 2017

Abstract

A positive crankcase ventilation (PCV) system for an engine includes: a PCV tube defining a flowpath extending along an axis; a damage detection circuit associated with the PCV tube. The PCV system also includes a damage detection module that selectively indicates that a fault is present in the PCV tube based on a change in a characteristic of the damage detection circuit and that illuminates a malfunction indicator lamp (MIL) when the fault is present.

First claim

What is claimed is:

1. A positive crankcase ventilation (PCV) system for an engine, the PCV system comprising:
a PCV tube that defines a flowpath extending along an axis;
a damage detection circuit that is associated with the PCV tube and that includes:
a first conductor that includes a first plurality of helical wraps defining a left handed helix; and
a second conductor that includes a second plurality of helical wraps defining a right handed helix and that is electrically connected to the first conductor,
wherein the left handed helix has a first diameter,
wherein the right handed helix has a second diameter that is less than the first diameter, and
wherein a first distance between each of the helical wraps of the first plurality of helical wraps is less than a second distance between each of the helical wraps of the second plurality of helical wraps; and

a damage detection module that selectively indicates that a fault is present in the PCV tube based on a change in a characteristic of the damage detection circuit and that illuminates a malfunction indicator lamp (MIL) when the fault is present.

2. The PCV system of claim 1 , wherein damage detection circuit is integrally formed with the PCV tube.

3. The PCV system of claim 1 , wherein the damage detection circuit is molded into the PCV tube.

4. The PCV system of claim 1 , wherein at least one of the first distance and the second distance is less than a flowpath dimension that is perpendicular to the axis.

5. The PCV system of claim 4 , wherein the first distance and the second distance is less than the flowpath dimension.

6. The PCV system of claim 1 , wherein the damage detection module indicates that the fault is present in the PCV tube when a difference between an electrical resistance of the damage detection circuit and a previous electrical resistance of the damage detection circuit is greater than a predetermined value.

7. The PCV system of claim 1 , wherein the damage detection module stores a predetermined diagnostic trouble code (DTC) associated with the fault in the PCV tube in memory when the fault is present.

8. A method for indicating the presence of a fault in a positive crankcase ventilation (PCV) tube of a vehicle, the method comprising:
receiving input indicative of a characteristic of a damage detection circuit associated with the PCV tube,
the PCV tube defining a flowpath extending along an axis, and
the damage detection circuit including:
a first conductor that includes a first plurality of helical wraps defining a left handed helix; and
a second conductor that includes a second plurality of helical wraps defining a right handed helix and that is electrically connected to the first conductor,
wherein the left handed helix has a first diameter,
wherein the right handed helix has a second diameter that is less than the first diameter, and
wherein a first distance between each of the helical wraps of the first plurality of helical wraps is less than a second distance between each of the helical wraps of the second plurality of helical wraps; and

selectively indicating that a fault is present in the PCV tube based on a change in the characteristic of the damage detection circuit; and
illuminating a malfunction indicator lamp (MIL) when the fault is present.

9. The method of claim 8 , wherein the damage detection circuit is integrally formed with the PCV tube.

10. The method of claim 8 , wherein the damage detection circuit is molded into the PCV tube.

11. The method of claim 8 , wherein at least one of the first distance and the second distance is less than a flowpath dimension that is perpendicular to the axis.

12. The method of claim 8 , wherein selectively indicating that a fault is present in the PCV tube includes indicating that the fault is present in the PCV tube when a difference between an electrical resistance of the damage detection circuit and a previous electrical resistance of the damage detection circuit is greater than a predetermined value.

13. The method of claim 8 further comprising storing a predetermined diagnostic trouble code (DTC) associated with the fault in the PCV tube in memory when the fault is present.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Jones Marie-Christine G

Classifications

• G01M3/182

  for tubes · CPC title

• G01M3/165

  by means of cables or similar elongated devices, e.g. tapes · CPC title

• F01M1/02

  using lubricating pumps (pumps in general F04; lubricating pumps per se F16N) · CPC title

• G01M3/187

  for flexible or elastic containers · CPC title

• F01M13/00

  Crankcase ventilating or breathing · CPC title