Engine automatic stop/start mechanism

• US 9,410,523 B2
• Filed: 10/09/2015
• Issued: 08/09/2016
• Est. Priority Date: 08/31/2011
• Status: Active Grant

• Current Assignee: BAE Systems Controls Incorporated (BAE Systems Plc)
• Original Assignee: BAE Systems Controls Incorporated (BAE Systems Plc)
• Inventors: Dupuy, James A.
• Primary Examiner(s): Chen, Shelley
• Application Number:
  US14/879,729
• Publication Number:
  US 20160115930A1
• Time in Patent Office: 305 Days
• Field of Search: 701/112, 701/113
• US Class Current: 1/1
• CPC Class Codes: F02D 17/04 rendering engines inoperative or idling, e.g. caused by abnormal conditions dependent on lubricating conditions F01M1/22; dependent on cooling F01P5/14
• CPC Class Codes: F02D 2200/501 Vehicle speed
• CPC Class Codes: F02D 2200/604 Engine control mode selected by driver, e.g. to manually start particle filter regeneration or to select driving style
• CPC Class Codes: F02D 29/02 peculiar to engines driving vehicles; peculiar to engines driving variable pitch propellers
• CPC Class Codes: F02N 11/0822 related to action of the driver
• CPC Class Codes: F02N 11/0825 related to prevention of engine restart failure, e.g. disabling automatic stop at low battery state
• CPC Class Codes: F02N 11/0829 related to special engine control, e.g. giving priority to engine warming-up or learning
• CPC Class Codes: F02N 2200/023 Engine temperature
• CPC Class Codes: F02N 2200/061 Battery state of charge [SOC]
• CPC Class Codes: F02N 2200/0801 Vehicle speed
• CPC Class Codes: Y02T 10/40 Engine management systems
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

An inventive system and method for managing vehicle power is presented. The novel technology provides a means to automatically shutdown a vehicle'"'"'s engine when conditions are such that engine power is not needed, reducing fuel consumption as well as lowering noise and emissions. A series of conditions are examined to determine whether engine power is needed and hence whether shutdown can be safely performed. The inventive system and method can also determine when power is again needed by the engine and can re-start the engine automatically at such times.

Claims

1. A method for performing automatic engine start of a hybrid vehicle having a battery, the method comprising steps of:

determining whether the engine was shutdown using automatic shutdown;

determining whether automatic engine authorization is asserted;

determining whether a state of charge of the battery is below a predetermined charge limit;

determining whether engine coolant temperature is below a predetermined temperature limit;

determining whether throttle depression is greater than a predetermined throttle limit;

determining whether the vehicle speed is greater than a predetermined speed limit; and

performing the automatic engine start when the engine was shutdown using the automatic shutdown, the automatic engine authorization is asserted, and at least one of;

the state of charge of the battery is below the predetermined charge limit, the engine coolant temperature is below the predetermined temperature limit, the throttle depression is greater than the predetermined throttle limit, and the vehicle speed is greater than the predetermined speed limit.

2. A system for performing automatic engine start, the system comprising:

a hybrid vehicle having an engine and a battery; and

a module operable to determine whether the engine was shutdown using automatic shutdown and whether automatic engine authorization is asserted and whether a state of charge of the battery is below a predetermined charge limit and whether engine coolant temperature is below a predetermined temperature limit and whether throttle depression is greater than a predetermined throttle limit and whether the vehicle speed is greater than a predetermined speed limit; and

wherein the module is further operable to perform the automatic engine start when the engine was shutdown using the automatic shutdown, the automatic engine authorization is asserted, and at least one of;

the state of charge of the battery is below the predetermined charge limit, the engine coolant temperature is below the predetermined temperature limit, the throttle depression is greater than the predetermined throttle limit, and the vehicle speed is greater than the predetermined speed limit.

3. A computer readable storage medium storing a program of instructions executable by a machine to perform automatic engine start for a hybrid vehicle having an engine and a battery, the program of instructions being configured to provide steps comprising:

determining whether the engine was shutdown using automatic shutdown;

determining whether automatic engine authorization is asserted;

determining whether a state of charge of the battery is below a predetermined charge limit;

determining whether engine coolant temperature is below a predetermined temperature limit;

determining whether throttle depression is greater than a predetermined throttle limit;

determining whether the vehicle speed is greater than a predetermined speed limit; and

performing the automatic engine start when the engine was shutdown using the automatic shutdown, the automatic engine authorization is asserted, and at least one of;

the state of charge of the battery is below the predetermined charge limit, the engine coolant temperature is below the predetermined temperature limit, the throttle depression is greater than the predetermined throttle limit, and the vehicle speed is greater than the predetermined speed limit.