Apparatus and method for controlling the air flow into an engine

• US 6,055,811 A
• Filed: 04/15/1998
• Issued: 05/02/2000
• Est. Priority Date: 04/15/1998
• Status: Expired due to Fees

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Tran, David, Maddock, James B., Mehdian, Fred
• Primary Examiner(s): Kamen, Noah P.
• Application Number:
  US09/060,666
• Time in Patent Office: 748 Days
• Field of Search: 60/600, 60/602
• US Class Current: 60/602
• CPC Class Codes: F02B 37/18 by bypassing exhaust from the inlet to the outlet of turbine or to the atmosphere
• CPC Class Codes: F02B 37/225 air passages
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

The present invention includes a method and apparatus for controlling the air flow into an engine. The engine has a wastegate and a choke valve. The method includes the steps of determining an air pressure within the intake manifold and comparing the air pressure to a desired air pressure. A position of the choke valve and wastegate is then determined in response to the comparison. The apparatus includes an air pressure sensor for sensing the actual air pressure within the intake manifold. A controlling means compares the actual air pressure with a desired air pressure and responsively determines a position of the choke valve and the wastegate. A choke valve actuator and wastegate actuator position the choke valve and the wastegate respectively.

Claims

1. A method for controlling the air flow into an engine having an intake manifold, a wastegate and a choke valve, comprising:

determining an actual air pressure within the intake manifold;

comparing said actual air pressures to a desired air pressure;

determining a position of the choke valve in response to said comparison;

determining a wastegate position is a predetermined position when said desired air pressure is less than a first threshold;

determining said wastegate position in response to said comparison when said desired air pressure is one of greater than and equal to said first threshold; and

controlling said choke valve and said wastegate in response to said position determinations, thereby controlling the air flow into the engine.

2. A method as set forth in claim 1, wherein the step of determining said wastegate position in response to said comparison includes the step of determining said desired air pressure is greater than said actual air pressure.

3. A method, as set forth in claim 2, wherein the step of determining said wastegate position in response to said comparison includes the step of determining said choke valve position can not be modified to increase said actual air pressure to said desired air pressure.

4. A method as set forth in claim 1, wherein the step of determining a choke valve position further comprises the step of determining said choke valve position in response to said comparison and said wastegate position.

5. A method as set forth in claim 4, wherein the step of determining said choke valve position includes the step of determining said desired air pressure is less than said actual air pressure.

6. A method, as set forth in claim 5, wherein the step of determining said choke valve position includes the step of determining said wastegate position may not be modified to decrease said actual air pressure to said desired air pressures.

7. A method, as set forth in claim 1, wherein the step of determining said choke valve position further comprises the steps of:

determining said choke valve position is a predetermined position when said desired air pressure is one of greater than and equal to a first threshold; and

determining said choke valve position in response to said comparison when said desired air pressure is less than said first threshold.

8. A method for controlling the air flow into an engine having an intake manifold, a wastegate and a choke valve, comprising:

determining an actual air pressure within the intake manifold;

comparing said actual air pressures to a desired air pressure;

determining a choke valve position is a predetermined position when said desired air pressure is one of greater than and equal to a first threshold; and

determining said choke valve position in response to said comparison when said desired air pressure is less than said first threshold;

determining a position of the wastegate in response to said comparison; and

controlling said choke valve and said wastegate in response to said position determinations, thereby controlling the air flow into the engine.