Control system for internal combustion engine

Patent metadata

Field	Value
Publication number	US-10598077-B2
Application number	US-201715695432-A
Country	US
Kind code	B2
Filing date	Sep 5, 2017
Priority date	Sep 7, 2016
Publication date	Mar 24, 2020
Grant date	Mar 24, 2020

Abstract

An ECU includes a motor control unit that controls energization to a motor, and a fixation determination unit that makes a determination on fixation of a valve body. The motor drives the valve body housed in a housing of a control valve. When the fixation determination unit has determined that the valve body is fixed, the motor control unit performs fixation-time control that energizes the motor so as to drive the valve body.

First claim

What is claimed is:

1. A control system for an internal combustion engine, the internal combustion engine provided with a cooling system, the cooling system including:
a pump configured to circulate a cooling liquid in a circulation path of the internal combustion engine, and
a control valve configured to control a flow of the cooling liquid in the circulation path by driving a valve body housed in a housing, with a motor,
the control system comprising:
an electronic control unit configured to:
(i) control energization to the motor,
(ii) make a determination on fixation of the valve body,
(iii) perform fixation-time control that energizes the motor so as to drive the valve body, when the electronic control unit determines that the valve body is fixed,
(iv) acquire an amount of movement of the valve body from a signal that is output from a sensor that detects a position of the valve body,
(v) determine that the valve body is fixed based on the amount of movement of the valve body for a predetermined time period being less than a reference value, and
(vi) determine that the valve body is fixed when a predetermined state is continued for a certain time period longer than the predetermined time period, and the predetermined state is a state in which the amount of movement of the valve body for the predetermined time period is less than the reference value.

2. The control system according to claim 1 , wherein the predetermined state is a state in which a torque of the motor is equal to or more than a predetermined amount and the amount of movement of the valve body for the predetermined time period is less than the reference value.

3. A control system for an internal combustion engine, the internal combustion engine provided with a cooling system, the cooling system including:
a pump configured to circulate a cooling liquid in a circulation path of the internal combustion engine, and
a control valve configured to control a flow of the cooling liquid in the circulation path by driving a valve body housed in a housing, with a motor,
the control system comprising:
an electronic control unit configured to:
(i) control energization to the motor,
(ii) make a determination on fixation of the valve body,
(iii) perform fixation-time control that energizes the motor so as to drive the valve body, when the electronic control unit determines that the valve body is fixed,
(iv) acquire a signal that is output from a sensor that detects a position of the valve body, and perform feedback control that controls energization to the motor so as to cause the position of the valve body to coincide with a target position, and
(v) acquire a signal that is output from the sensor that detects the position of the valve body, to thereby acquire the position of the valve body, and determine that the valve body is fixed when a predetermined state is continued for a certain time period, and the predetermined state is a state in which a deviation between the target position in the feedback control and the position acquired from the signal that is output from the sensor is equal to or more than a reference amount.

4. The control system according to claim 1 , wherein
the electronic control unit is configured to control energization to the motor so as to produce a torque greater than a torque that is produced when the electronic control unit determines that the valve body is not fixed, in the fixation-time control.

5. The control system according to claim 1 , wherein
the valve body moves in a first direction or a second direction opposite to the first direction in the housing, and the electronic control unit is configured to control energization to the motor such that driving of the valve body in the first direction and driving of the valve body in the second direction are performed alternately, in the fixation-time control.

6. A control system for an internal combustion engine, the internal combustion engine provided with a cooling system, the cooling system including:
a pump configured to circulate a cooling liquid in a circulation path of the internal combustion engine, and
a control valve configured to control a flow of the cooling liquid in the circulation path by driving a valve body housed in a housing, with a motor,
the control system comprising:
an electronic control unit configured to:
(i) control energization to the motor,
(ii) make a determination on fixation of the valve body, and
(iii) perform fixation-time control that energizes the motor so as to drive the valve body, when the electronic control unit determines that the valve body is fixed, wherein

the valve body moves in a first direction or a second direction opposite to the first direction in the housing, and
when the electronic control unit starts the fixation-time control, the electronic control unit is configured to control energization to the motor so as to drive the valve body in a direction that is opposite to a direction when the electronic control unit determines that the valve body is fixed, among the first direction and the second direction.

7. The control system according to claim 6 , wherein
the valve body moves in the first direction or the second direction opposite to the first direction in a predetermined range until abutting a stopper in the housing, and the electronic control unit is configured to: when the electronic control unit starts the fixation-time control and a distance from the valve body to the stopper in one of the first direction and the second direction is less than a predetermined distance,
(i) not perform the process to control energization to the motor so as to drive the valve body in a direction that is opposite to a direction when the electronic control unit determines that the valve body is fixed, among the first direction and the second direction, and control energization to the motor so as to drive the valve body in the other of the first direction and the second direction, in the fixation-time control, and
(ii) not perform the process to control energization to the motor so as to drive the valve body in a direction that is opposite to a direction when the electronic control unit determines that the valve body is fixed, among the first direction and the second direction, and control energization to the motor so as not to drive the valve body in the one of the first direction and the second direction, in the fixation-time control.

8. The control system according to claim 1 , wherein
the valve body moves in a first direction or a second direction opposite to the first direction in a predetermined range until abutting a stopper in the housing, and the electronic control unit is configured to: when the electronic control unit starts the fixation-time control and a distance from the valve body to the stopper in one of the first direction and the second direction is less than a predetermined distance,
(i) control energization to the motor so as to drive the valve body in the other of the first direction and the second direction, in the fixation-time control, and
(ii) control energization to the motor so as not to drive the valve body in the one of the first direction and the second direction, in the fixation-time control.

9. A control system for an internal combustion engine, the internal combustion engine provided with a cooling system, the cooling system including:
a pump configured to circulate a cooling liquid in a circulation path of the internal combustion engine, and
a control valve configured to control a flow of the cooling liquid in the circulation path by driving a valve body housed in a housing, with a motor,
the control system comprising:
an electronic control unit configured to:
(i) control energization to t

Assignees

• Toyota Motor Co Ltd

Inventors

• Kaneko Rihito
• Takagi Noboru
• Takagi Isao
• Hisaminato Naoto
• Yamaguchi Mitsuru
• Ando Hirokazu
• Onoda Hidetoshi
• Akeyama Hiroshi

Classifications

• F01P2037/00

  Controlling · CPC title

• F01P7/14 Primary

  the coolant being liquid · CPC title

• F01P5/12

  Pump-driving arrangements · CPC title

• F01P2007/146

  using valves · CPC title

• F01P11/14

  Indicating devices; Other safety devices · CPC title