Siloxane filter for O2 sensor for bio-gas engine

• US 6,365,108 B1
• Filed: 10/12/1999
• Issued: 04/02/2002
• Est. Priority Date: 10/12/1999
• Status: Expired due to Fees

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Philyaw, Dale A.
• Primary Examiner(s): Warden, Jill
• Assistant Examiner(s): Sines, Brian J.
• Application Number:
  US09/416,439
• Time in Patent Office: 903 Days
• Field of Search: 204/426, 204/427, 552/823, 55/16, 123/527, 429/13, 95/45, 422/98
• US Class Current: 422/98
• CPC Class Codes: B01D 46/106 Ring-shaped filtering elements
• CPC Class Codes: G01N 33/0014 by eliminating a gas G01N33/0013 and G01N33/0024 take precedence

Abstract

A siloxane filter system for protecting an oxygen probe utilized in an internal combustion engine fueled by bio-gases, the filter system having a stainless fiber filter removably disposed in a housing having and inlet port and an outlet port disposed in fluid communication with an exhaust duct in such a manner as to cause exhaust gases to flow through the housing and filter, the oxygen probe is disposed in the housing down stream of the filter, causing siloxane in the exhaust gases to be deposited on the stainless fibers of the filter and essentially siloxane free gases passes over the oxygen probe extending its useful life.

Claims

1. A siloxane filter system for protecting an oxygen probe utilized in an internal combustion engine having an exhaust duct and being fueled by landfill gases, the siloxane filter system comprising a fiber filter removably disposed in a housing, the housing having an outer cylindrical portion disposed between two end plates bored to receive the outer cylindrical portion, one of the end plates having four bores the largest bore receiving the outer cylindrical portion the second largest bore having a diameter generally equal to the inside diameter of the outer cylindrical portion and the next smaller bore having a diameter that receives an inner cylindrical portion that does not extend to the other end plate, an inlet port and an outlet port disposed in fluid communication with the exhaust duct in such a manner as to cause exhaust gases to flow through the housing and filter, the outlet port being disposed in fluid communication with the second largest bore and the inlet port being so disposed in a side of the one end plate to cause the influent exhaust gasses to swirl in the second largest bore, the other end plate having a central threaded opening for receiving the oxygen probe and the fiber filter being disposed in the housing between the inner and outer cylindrical members filtering the exhaust gases of siloxane prior to contacting the oxygen probe, whereby siloxane in the exhaust gases is deposited on the fibers of the filter and essentially siloxane free gases pass over the oxygen probe, extending its useful life.

2. A siloxane filter system for protecting an oxygen probe utilized in an internal combustion engine having an exhaust duct and being fueled by bio-gases, the siloxane filter system comprising a plate disposed in the exhaust duct and having an opening that generally mates with the opening in the exhaust duct and an enlarged portion on one side of the plate having a large bore therein forming a housing, a fiber filter removably disposed in the housing, the housing having and inlet port and an outlet port disposed in fluid communication with the exhaust duct in such a manner as to cause exhaust gases to flow through the housing and filter, the oxygen probe being disposed in the housing down stream of the filter, whereby siloxane in the exhaust gases is deposited on the fibers of the filter and essentially siloxane free gases passes over the oxygen probe extending its useful life.

3. A siloxane filter system as set forth in claim 2, wherein the counter bore is above the main portion of the plate.

4. The siloxane filter system as set forth in claim 3, wherein the opening in the plate that mates with the opening in the exhaust duct has a portion that protrudes into the opening and the inlet and outlet ports, respectively, originate and terminate in the protruding portion.

5. The siloxane filter system as set forth in claim 4, wherein the protruding portion is beveled on both upstream and downstream sides.

6. The siloxane filter system as set forth in claim 5, wherein the inlet port originates in the upstream bevel and the outlet port terminates in the downstream bevel.

7. The siloxane filter system as set forth in claim 6, wherein a portion of the inlet port and a portion of the outlet port is generally perpendicular to the associated bevel on the protruding portion whereby the inlet and outlet ports act in combination to provide the correct flow of filtered gas over the oxygen probe.

8. The siloxane filter system as set forth in claim 7, wherein the inlet port is sloped downwardly to allow water to drain from the inlet port.

9. The siloxane filter system as set forth in claim 8, wherein the inlet port is sloped downwardly to allow water to drain from the inlet port.

10. The siloxane filter system as set forth in claim 9, wherein the filter fibers are stainless steel.