Apparatus for starting engine and method of controlling engine

• US 8,812,222 B2
• Filed: 09/29/2011
• Issued: 08/19/2014
• Est. Priority Date: 09/29/2011
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Kondo, Yumi, Yoshitomi, Yuuya, Kawai, Toshihiro
• Primary Examiner(s): Kwon, John
• Assistant Examiner(s): Hoang, Johnny H
• Application Number:
  US13/702,848
• Publication Number:
  US 20130325304A1
• Time in Patent Office: 1,055 Days
• Field of Search: 701/101, 701/102, 701/107, 701112-114, 123/179.1, 123/179.4, 123/179.25, 123/198.D, 123/198.DB, 123/198.DC, 123/198.F, 123/339.1, 123/339.14, 123/339.15, 123/339.25, 290/38.B, 290/38.C, 290/38.E, 290/38.R
• US Class Current: 701/113
• CPC Class Codes: F02D 29/02 peculiar to engines driving vehicles; peculiar to engines driving variable pitch propellers
• 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 11/0855 during engine shutdown or after engine stop before start command, e.g. pre-engagement of pinion
• CPC Class Codes: F02N 2200/063 Battery voltage
• CPC Class Codes: F02N 2250/02 Battery voltage drop at start, e.g. drops causing ECU reset
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A starter includes a pinion gear that can be engaged with a ring gear coupled to a crank shaft of an engine, an actuator that moves the pinion gear to a position where the pinion gear is engaged with a ring gear, and a motor that rotates the pinion gear. An ECU stops the engine when a predetermined stop condition is satisfied, and cranks the engine with a motor when a predetermined start condition is satisfied after the engine is stopped. The motor and the actuator are supplied with electric power from a battery. The ECU includes a mode in which the motor is driven prior to driving of the actuator. The ECU restricts a stop of the engine if, of a decreased voltage of the battery after driving the motor and a decreased voltage of the battery after driving the actuator, the lower voltage falls below a threshold value.

Claims

1. An apparatus for starting an engine that automatically stops based on a predetermined condition, comprising:

a starter that starts said engine;

a battery that supplies electric power to said starter; and

a control device for controlling said starter,

said starter including

a second gear that can be engaged with a first gear coupled to a crank shaft of said engine,

an actuator that moves, in a driving state, said second gear to a position where said second gear is engaged with said first gear, and

a motor that rotates said second gear,

wherein said control device

can drive each of said actuator and said motor individually,

has a rotation mode in which said motor is driven prior to driving of said actuator, and

when said rotation mode is executed, restricts an automatic stop of said engine based on a lower voltage of a decreased voltage of said battery after driving said motor and a decreased voltage of said battery after driving said actuator.

2. The apparatus according to claim 1, wherein said control device

further has an engagement mode in which said actuator is driven to bring said second gear into engagement with said first gear prior to driving of said motor, and

when said engagement mode is executed, restricts an automatic stop of said engine based on a decreased voltage after driving said motor.

4. The apparatus according to claim 1, wherein when a lower voltage of a minimum voltage value of said battery after driving said motor and before driving said actuator and a minimum voltage value of said battery after driving said actuator in addition to driving said motor falls below a threshold value, said control device restricts an automatic stop of said engine.

3. A method of controlling an engine that automatically stops based on a predetermined condition, said engine being provided with a starter including a second gear that can be engaged with a first gear coupled to a crank shaft, an actuator that moves, in a driving state, said second gear to a position where said second gear is engaged with said first gear, and a motor that rotates said second gear, said starter being supplied with electric power from a battery, said method comprising the steps of:

driving said motor prior to driving of said actuator; and

restricting an automatic stop of said engine based on a lower voltage of a decreased voltage of said battery after driving said motor and a decreased voltage of said battery after driving said actuator.