Gas sensor assembly

• US 8,057,741 B2
• Filed: 12/22/2008
• Issued: 11/15/2011
• Est. Priority Date: 12/22/2008
• Status: Expired due to Fees

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Gustin, Ronald R.
• Primary Examiner(s): Ramdhanie; Bobby
• Application Number:
  US12/341,069
• Publication Number:
  US 20100158758A1
• Time in Patent Office: 1,058 Days
• Field of Search: 422/94
• US Class Current: 422/94
• CPC Class Codes: F01N 13/008 Mounting or arrangement of exhaust sensors in or on exhaust apparatus sensor arrangements for engine control F02D41/1439
• CPC Class Codes: G01N 33/0013 by a chemical reaction G01N33/0024 takes precedence
• CPC Class Codes: G01N 33/0037 for NOx
• CPC Class Codes: Y02A 50/20 Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
• CPC Class Codes: Y10T 29/49345 Catalytic device making

Abstract

A gas sensor assembly may include a housing defining a chamber. A gas sensor may be mounted in the chamber. An inlet tube may be secured to the housing and extend into the chamber of the housing. The inlet tube may define a passage providing fluid communication between outside the housing and the chamber of the housing.

Claims

1. A gas sensor assembly comprising:

a housing comprising a first longitudinal end portion and a second longitudinal end portion defining a chamber wherein the second longitudinal end portion has a first end proximate the first longitudinal end portion and an oppositely disposed second end;

a gas sensor mounted in the chamber;

a mounting component connected to the second end of the second longitudinal end portion and having first and second openings there through placing the exterior of the housing in fluid communication with the chamber;

an inlet tube having a first end secured to the first opening of the mounting component and extending into the chamber of the housing, the inlet tube defining a passage providing fluid communication between outside the housing and the chamber of the housing; and

an outlet tube having a first end secured to the second opening of the mounting component and extending into the chamber of the housing, the outlet tube defining a passage providing fluid communication between outside the housing and the chamber of the housing, wherein fluid from outside the housing enters the chamber through the first opening and the inlet tube, contacts the gas sensor, and exits the chamber to outside the housing through the outlet tube and the second opening.

2. A gas sensor assembly as set forth in claim 1, wherein the inlet tube contains a catalyst material.

3. A gas sensor assembly as set forth in claim 1, wherein the housing includes a shell having a length extending between opposite longitudinal ends, at least a portion of the gas sensor being between the inlet tube and the outlet tube in a transverse direction relative with respect to the shell.

4. A gas sensor assembly as set forth in claim 3, wherein the gas sensor includes a heating element, the heating element being between the inlet tube and the outlet tube.

5. A gas sensor assembly as set forth in claim 4, wherein a portion of the exterior surface of the inlet tube is in thermal contact with the heating element.

6. A gas sensor assembly as set forth in claim 5, wherein the portion of the exterior surface of the inlet tube in thermal contact with the heating element is generally planar.

7. A gas sensor assembly as set forth in claim 1, further including a cover secured to the mounting component outside the housing, the mounting component and the cover together defining an inlet port at the first opening in fluid communication with the inlet tube and an outlet port at the second opening in fluid communication with the outlet tube.

8. A gas sensor assembly as set forth in claim 3, wherein the inlet port and the outlet port extend generally transversely with respect to the shell.

9. A gas sensor assembly as set forth in claim 1, further including a housing mount, the housing mount including a mounting boss defining an axial opening extending through opposite longitudinal ends of the boss, the axial opening being sized and shaped to receive the gas sensor assembly and to secure the gas sensor assembly to an exhaust system of a machine, and a heat shield extending axially outward from one of the longitudinal ends of the mounting boss with respect to the axial opening of the boss, the heat shield adapted to surround at least a longitudinal portion of the gas sensor assembly when the gas sensor assembly is secured to the boss.

10. A gas sensor assembly as set forth in claim 9, wherein an exhaust system of a machine, to which the gas sensor assembly includes a gas conduit, with the gas conduit defining an exhaust passage through which exhaust gases flow, wherein the housing mount is secured to the gas conduit and extends into the exhaust passage so that at least a portion of the heat shield is in the exhaust passage, wherein the housing is mounted on the housing mount so that the inlet tube is in fluid communication with the exhaust passage.

11. A gas sensor assembly as set forth in claim 1, wherein the mounting component further includes first and second transverse openings fluidly connected to the respective first and second openings and extending generally transversely with respect to the shell.

12. A gas sensor assembly as set forth in claim 3, wherein each of the inlet tube passage and the outlet tube passage includes an exposed transverse opening outside the housing and the mounting component and extending generally transversely with respect to the shell.

13. A gas sensor assembly comprising:

a housing defining a chamber and having a length extending between opposite longitudinal ends;

a gas sensor in the chamber extending longitudinally with respect to the housing;

a mounting component connected to an end of a portion of the housing defining of the chamber and having first and second openings there through placing the interior of the chamber in fluid communication with an exterior of the housing;

an inlet tube having a first end secured to the first opening of the mounting component and extending into the chamber of the housing, the inlet tube defining a passage extending longitudinally with respect to the housing and being arranged to provide fluid communication between outside the housing and the chamber of the housing;

an outlet tube having a first end secured to the second opening of the mounting component and extending into the chamber of the housing, the outlet tube defining a passage extending longitudinally with respect to the housing and being arranged so as to provide fluid communication between outside the housing and the chamber of the housing; and

wherein the gas sensor is positioned between the inlet tube and the outlet tube inside the chamber such that fluid from outside the housing enters the chamber through the first opening and the inlet tube, contacts the gas sensor, and exits the chamber through the outlet tube and the second opening.

14. A gas sensor assembly as set forth in claim 13, wherein the inlet tube includes a catalyst material in the passage of the inlet tube.