Method and apparatus for indicating air filter maintenance is required

• US 20050240338A1
• Filed: 04/23/2004
• Published: 10/27/2005
• Est. Priority Date: 04/23/2004
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Motor Company
• Inventors: Ardisana, John Bernard
• Granted Patent: US 7,032,573 B2
• Time in Patent Office: Days
• US Class Current: 701/114
• CPC Class Codes: F02D 41/18 by measuring intake air flow
• CPC Class Codes: F02D 41/22 Safety or indicating devices for abnormal conditions in air/fuel ratio feedback systems F02D41/1495, in electric control linkage F02D11/107, in purge control systems F02M25/0809
• CPC Class Codes: F02M 35/024 using filters, e.g. moistened F02M35/026 takes precedence; cleaning of the filtering material F02M35/08
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A system and method for indicating required maintenance of an air filter used with an internal combustion engine. The system includes a throttle plate for adjusting an amount of airflow passing into cylinders of the engine. The system includes a throttle plate position sensor and a processor. The processor is responsive to a throttle plate position signal produced by the throttle plate sensor, for determining, as a function of such throttle plate position signal, whether the air filter is in need of maintenance. When a manifold absolute pressure sensor is provided, the processor is responsive to a first reading of such manifold absolute pressure sensor taken at a first time and at a second reading of the manifold absolute pressure sensor taken at a second time, for determining, as a function of a difference between such first and second readings whether the air filter is in need of maintenance.

Claims

1. A system for indicating required maintenance of an air filter used with an internal combustion engine, such engine including a throttle plate for adjusting an amount of air flow passing into cylinders of the engine, such system comprising:

a throttle plate position sensor;

a processor responsive to a throttle plate position signal produced by the throttle plate sensor, for determining, as a function of such throttle plate position signal, whether the air filter is in need of maintenance.

2. The system recited in claim 1 including a manifold absolute pressure sensor disposed between the throttle plate and the cylinders, and wherein the processor is responsive to the throttle plate position signal and a signal produced by the manifold absolute pressure sensor, for determining, as a function of such throttle plate position signal and manifold absolute pressure sensor, whether the air filter is in need of maintenance.

3. The system recited in claim 1 including:

a mass air flow sensor disposed downstream of the air filter;

wherein the processor includes a table storing a relationship between throttle plate position and expected air mass flow into the cylinders as a function of engine speed;

wherein the processor is responsive to a signal indicative of engine speed and the throttle plate position signal for determining from the table an expected air flow;

wherein the processor determines a difference between the determined expected air flow and a signal produced by the mass air flow sensor, for determining, as a function of such difference, whether the air filter is in need of maintenance.

4. The system recited in claim 1 including a manifold absolute pressure sensor disposed between the throttle plate and the cylinders, and wherein the processor is responsive to a first reading of such manifold absolute pressure sensor taken at a first time and at a second reading of the manifold absolute pressure sensor taken at a second time, for determining, as a function of a difference between such first and second readings whether the air filter is in need of maintenance.

5. A system for indicating required maintenance of an air filter used with an internal combustion engine, such system comprising:

a manifold absolute pressure sensor; and

a processor, responsive to a first reading of such manifold absolute pressure sensor taken at a first time and at a second reading of the manifold absolute pressure sensor taken at a second time, for determining, as a function of a difference between such first and second readings whether the air filter is in need of maintenance.

8. The method recited in claim 5 wherein the air filter maintenance determining is a function a signal indicative of engine speed and the throttle plate position signal for determining an expected air flow, and a difference between the determined expected air flow and a signal produced by an mass air flow sensor.

9. The method recited in claim 8 wherein the air filter maintenance determining is a function a difference between a first reading of the manifold absolute pressure sensor taken at a first time and at a second reading of the manifold absolute pressure sensor taken at a second time.

10. The method recited in claim 9 wherein the first reading is representative of barometric pressure.

11. The method recited in claim 10 wherein the first reading is taken at engine power-up.

20. The article of manufacture recited in claim 10 wherein the first reading is taken at engine power-up.

6. A method for indicating required maintenance of an air filter used with an internal combustion engine, such engine including a throttle plate for adjusting an amount of air flow passing into cylinders of the engine, such method comprising:

determining, as a function of a throttle plate position signal produced by a throttle plate position sensor, whether the air filter is in need of maintenance.

7. The method recited in claim 6 wherein the air filter maintenance determining is a function of the throttle plate position signal and a signal produced by an manifold absolute pressure sensor disposed between the throttle plate and the cylinders.

12. A method for indicating required maintenance of an air filter used with an internal combustion engine, comprising:

obtaining a first reading of a manifold absolute pressure sensor at a first time and at a second reading of the manifold absolute pressure sensor taken at a second time; and

determining, as a function of a difference between such first and second readings whether the air filter is in need of maintenance.

13. The method recited in claim 12 wherein the first reading is representative of barometric pressure.

14. The method recited in claim 13 wherein the first reading is taken at engine power-up.

15. An article of manufacture comprising:

a computer storage medium having a computer program encoded therein code for determining, as a function of a throttle plate position signal produced by a throttle plate position sensor, whether the air filter is in need of maintenance.

16. The article of manufacture recited in claim 15 including code for determining air filter maintenance as a function of the throttle plate position signal and a signal produced by an manifold absolute pressure sensor.

17. The article of manufacture recited in claim 16 including code for determining air filter maintenance as a function a signal indicative of engine speed and the throttle plate position signal to determining an expected air flow, and a difference between the determined expected air flow and a signal produced by an mass air flow sensor.

18. The article of manufacture recited in claim 17 including code for determining a difference between a first reading of a manifold absolute pressure sensor taken at a first time and at a second reading of the manifold absolute pressure sensor taken at a second time.

19. The article of manufacture recited in claim 18 wherein the first reading is representative of barometric pressure.

24. The article of manufacture recited in claim 15 wherein the computer storage medium is a semiconductor chip.

25. The article of manufacture recited in claim 16 wherein the computer storage medium is a semiconductor chip.

26. The article of manufacture recited in claim 17 wherein the computer storage medium is a semiconductor chip.

27. The article of manufacture recited in claim 18 wherein the computer storage medium is a semiconductor chip.

21. An article of manufacture comprising:

a computer storage medium having a computer program encoded therein code for determining, as a function an obtaining first reading of a manifold absolute pressure sensor at a first time and at a second reading of the manifold absolute pressure sensor taken at a second time and a function of a difference between such first and second readings whether the air filter is in need of maintenance.

22. The article of manufacture recited in claim 21 wherein the first reading is representative of barometric pressure.

23. The article of manufacture claim 22 wherein the first reading is taken at engine power-up.

28. The article of manufacture recited in claim 21 wherein the computer storage medium is a semiconductor chip.