IP Library › Granted Patent US 10,753,262

Granted Patent B2

US 10,753,262 · App. 15/482,217 · Granted Aug 25, 2020

Control system of exhaust sensor

Inventor: Go Hayashita (Chigasaki, JP)

Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA

F01N11/007 F01N9/00 G01N27/4071 G01N27/4075 F01N2560/02 F01N2560/025 F01N2560/20 G01N27/4067 Y02T10/47

View Patent ↗

Loading inventors, assignments & file history…

Monitor This Case

Get email alerts when status or documents change.

Order Certified Copies

Most orders are placed with the USPTO same day — all within 24 business hours.

Order via The Patent Place →

Pre-filled with this patent's details

Quick Facts

Patent No.: US 10,753,262
App. No.: 15/482,217
Granted: Aug 25, 2020
Kind: B2

External Links

USPTO Patent Center↗ Full Patent PDF↗

Abstract

A control system of an exhaust sensor controlling an exhaust sensor comprises a heater control part controlling a heater and a temperature estimating part estimating a temperature of an exhaust pipe around the exhaust sensor. The heater control part sets the target temperature to a first target temperature after startup of the internal combustion engine and until the estimated temperature of the exhaust pipe reaches a first exhaust pipe temperature, sets the target temperature to a second target temperature from when the estimated temperature of the exhaust pipe reaches the first exhaust pipe temperature to when it reaches a second exhaust pipe temperature, and sets the target temperature to an operating temperature of the electrochemical cell when the estimated temperature of the exhaust pipe reaches the second exhaust pipe temperature.

Claims (81)

1. A control system of an exhaust sensor controlling the exhaust sensor arranged in an exhaust passage of an internal combustion engine and detecting a specific component in exhaust gas, wherein

the exhaust sensor comprises an element body provided with an electrochemical cell, a protective layer formed on an outer surface of the element body and comprised of a porous ceramic, and a heater heating the element body and the protective layer,

the control system comprises an electronic control unit (ECU), wherein

the ECU is programmed to

set a target temperature of the electrochemical cell,

control the heater so that a temperature of the electrochemical cell becomes the target temperature, and

estimate a temperature of an exhaust pipe around the exhaust sensor, wherein

the ECU is further programmed to

set the target temperature of the electrochemical cell to a first target temperature after startup of the internal combustion engine and until the estimated temperature of the exhaust pipe reaches a first exhaust pipe temperature,

set the target temperature of the electrochemical cell to a second target temperature from when the estimated temperature of the exhaust pipe reaches the first exhaust pipe temperature to when the estimated temperature of the exhaust pipe reaches a second exhaust pipe temperature, and

set the target temperature of the electrochemical cell to an operating temperature of the electrochemical cell when the estimated temperature of the exhaust pipe reaches the second exhaust pipe temperature, wherein

the first exhaust pipe temperature is a temperature of a dew point of water to less than a boiling point of water,

the second exhaust pipe temperature is a temperature of the boiling point of water or more,

the first target temperature is a temperature higher than the operating temperature, and

the second target temperature is a temperature higher than the operating temperature and lower than the first target temperature.

2. The control system of the exhaust sensor according to claim 1 , wherein

the ECU is further programmed to

estimate or detect an outside air temperature of the internal combustion engine, and

set the first target temperature higher when the estimated or detected outside air temperature at a time of startup of the internal combustion engine is lower than another detected outside air temperature.

3. The control system of the exhaust sensor according to claim 2 , wherein

the ECU is further programmed to

judge that the estimated temperature of the exhaust pipe has reached the first exhaust pipe temperature when an elapsed time from when the internal combustion engine is started up reaches a first elapsed time, and judge that the estimated temperature of the exhaust pipe has reached the second exhaust pipe temperature when the elapsed time reaches a second elapsed time longer than the first elapsed time,

estimate or detect the outside air temperature of the internal combustion engine, and

set the first elapsed time and the second elapsed time longer when the estimated or detected outside air temperature at the time of startup of the internal combustion engine is lower than another detected outside air temperature.

4. The control system of the exhaust sensor according to claim 3 , wherein

the control system further includes an upstream side exhaust sensor, and a downstream side exhaust sensor positioned at a downstream side of the upstream side exhaust sensor in a direction of exhaust flow, and

the ECU is further programmed to set the first target temperature and the second target temperature at the downstream side exhaust sensor higher than the first target temperature and the second target temperature at the upstream side exhaust sensor.

5. The control system of the exhaust sensor according to claim 2 , wherein

the ECU is further programmed to

judge that the estimated temperature of the exhaust pipe has reached the first exhaust pipe temperature when a cumulative value of an intake air amount supplied to combustion chambers of the internal combustion engine from when the internal combustion engine is started up reaches a first cumulative air amount, and judge that the estimated temperature of the exhaust pipe has reached the second exhaust pipe temperature when the cumulative value reaches a second cumulative air amount greater than the first cumulative air amount,

estimate or detect the outside air temperature of the internal combustion engine, and

set the first cumulative air amount and the second cumulative air amount greater when the estimated or detected outside air temperature at the time of startup of the internal combustion engine is lower than another detected outside air temperature.

6. The control system of the exhaust sensor according to claim 5 , wherein

7. The control system of the exhaust sensor according to claim 2 , wherein

8. The control system of the exhaust sensor according to claim 1 , wherein

the ECU is further programmed to

estimate or detect an outside air temperature of the internal combustion engine, and

set the first elapsed time and the second elapsed time longer when the estimated or detected outside air temperature at a time of startup of the internal combustion engine is lower than another detected outside air temperature.

9. The control system of the exhaust sensor according to claim 8 , wherein

10. The control system of the exhaust sensor according to claim 1 , wherein

the ECU is further programmed to

estimate or detect an outside air temperature of the internal combustion engine, and

set the first cumulative air amount and the second cumulative air amount greater when the estimated or detected outside air temperature at a time of startup of the internal combustion engine is lower than another detected outside air temperature.

11. The control system of the exhaust sensor according to claim 10 , wherein

12. The control system of the exhaust sensor according to claim 1 , wherein

13. A control system of an exhaust sensor controlling the exhaust sensor arranged in an exhaust passage of an internal combustion engine and detecting a specific component in exhaust gas, wherein

the control system comprises an electronic control unit (ECU), wherein

the ECU is programmed to

set a target temperature of the electrochemical cell,

control the heater so that a temperature of the electrochemical cell becomes the target temperature, and

estimate an amount of condensed water in the exhaust passage upstream from the exhaust sensor in a direction of exhaust flow, wherein

the ECU is programmed to make the target temperature higher as the amount of condensed water increases after startup of the internal combustion engine.

14. A control system of an exhaust sensor controlling the exhaust sensor arranged in an exhaust passage of an internal combustion engine and detecting a specific component in exhaust gas, wherein

the control system comprises an electronic control unit (ECU), wherein

the ECU is programmed to

estimate a temperature of an exhaust pipe around the exhaust sensor,

set a target temperature of the electrochemical cell to a first target temperature after startup of the internal combustion engine,

set the target temperature of the electrochemical cell to a second target temperature from when the estimated temperature of the exhaust pipe reaches a first exhaust pipe temperature to when the estimated temperature of the exhaust pipe reaches a second exhaust pipe temperature, and

the first exhaust pipe temperature is a temperature of a dew point of water to less than a boiling point of water,

the second exhaust pipe temperature is a temperature of the boiling point of water or more,

the first target temperature is a temperature higher than the operating temperature, and

the second target temperature is a temperature higher than the operating temperature and lower than the first target temperature, wherein

the ECU is programmed to

control the heater so that the temperature of the electrochemical cell becomes the first target temperature, and maintain the temperature of the electrochemical cell at the first target temperature until the estimated temperature of the exhaust pipe reaches the first exhaust pipe temperature;

control the heater so that the temperature of the electrochemical cell becomes the second target temperature, and maintain the temperature of the electrochemical cell at the second target temperature until the estimated temperature of the exhaust pipe reaches the second exhaust pipe temperature; and

control the heater so that the temperature of the electrochemical cell becomes the operating temperature.

Assignments (1)

ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Apr 7, 2017

From: HAYASHITA, GO

To: TOYOTA JIDOSHA KABUSHIKI KAISHA

Reel/Frame 041932/0564 →

Priority Claims (1)

JP 2015-079167 · Apr 11, 2016 · national

Continuity (1)

Related Publication 20170292433A1 · Oct 12, 2017