US20120035829A1 - Control device for internal combustion engine - Google Patents
Control device for internal combustion engine Download PDFInfo
- Publication number
- US20120035829A1 US20120035829A1 US13/264,087 US200913264087A US2012035829A1 US 20120035829 A1 US20120035829 A1 US 20120035829A1 US 200913264087 A US200913264087 A US 200913264087A US 2012035829 A1 US2012035829 A1 US 2012035829A1
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- United States
- Prior art keywords
- pump
- coolant
- exhaust gas
- internal combustion
- combustion engine
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
- F01P3/00—Liquid cooling
- F01P3/20—Cooling circuits not specific to a single part of engine or machine
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
- F01N3/04—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust using liquids
- F01N3/043—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust using liquids without contact between liquid and exhaust gases
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
- F01N3/04—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust using liquids
- F01N3/043—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust using liquids without contact between liquid and exhaust gases
- F01N3/046—Exhaust manifolds with cooling jacket
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
- F01P2060/00—Cooling circuits using auxiliaries
- F01P2060/16—Outlet manifold
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/12—Improving ICE efficiencies
Definitions
- the present invention relates to a control device for an internal combustion engine.
- cooling unit for cooling exhaust gases of an internal combustion engine.
- the cooling unit which is provided between an exhaust port and an exhaust manifold or which is provided around the exhaust manifold (See Patent Document 1).
- the exhaust gases are cooled with coolant water flowing through the cooling unit.
- Patent Document 1 Japanese Patent Application Publication No. 63-208607.
- Such a cooling unit is arranged on a path through which a coolant flows.
- the coolant is circulated through the path by a pump.
- such a cooling unit stores a part of the heat quantity of the exhaust gas.
- the pump is stopped and then the coolant is not circulated. For this reason, the heat quantity stored in the cooling unit is transmitted to the coolant, and then the coolant might boil.
- a control device for an internal combustion engine including: a cooling unit arranged on a path where a coolant is circulated, and cooling an exhaust gas of the internal combustion engine with the coolant flowing through the cooling unit; a pump circulating the coolant; an estimation portion estimating a heat quantity of the exhaust gas, and a control portion deciding whether or not to operate the pump after an ignition switch is detected to be OFF, in response to the estimated heat quantity of the exhaust gas.
- a control device of an internal combustion engine suppressing boiling of a coolant.
- FIG. 1 is an explanatory view of a control device for an internal combustion engine
- FIG. 2 is a view of a path of a coolant
- FIG. 3 is a flowchart of an example of a control performed by an ECU
- FIG. 4A is a map for calculating an exhaust gas temperature
- FIG. 4B is a map for calculating an idling period
- FIG. 5 is a timing chart to explain the control performed by the ECU
- FIG. 6 is a timing chart to explain the control performed by the ECU
- FIG. 7 is a view of a path of the coolant in the cooling device for the internal combustion engine according to a second embodiment
- FIG. 8 is a flowchart of an example of the control performed by the ECU
- FIG. 9 is an explanatory view of a path of the coolant in the cooling device for the internal combustion engine according to a third embodiment.
- FIG. 10 is a flowchart of an example of the control performed by the ECU.
- FIG. 1 is an explanatory view of a control device for an internal combustion engine.
- An engine 10 has a pair of banks 12 L and 12 R.
- the banks 12 L and 12 R are arranged obliquely to each other.
- the engine 10 is a so-called V-type engine.
- the bank 12 L has a cylinder group including three cylinders 14 L.
- the bank 12 R has cylinders 14 R.
- the bank 12 L is provided with fuel injection valves 15 L injecting fuel directly into the cylinders 14 L.
- the bank 12 R is provided with fuel injection valves 15 R injecting fuel directly into the cylinders 14 R.
- An intake path 4 L and an exhaust manifold 5 L are connected to the bank 12 L.
- An intake path 4 R and an exhaust manifold 5 R are connected to the bank 12 R.
- the intake paths 4 L and 4 R are jointed to each other at their upstream sides. The jointed portion is provided with a throttle valve 6 for adjusting intake air quantity and an airflow meter for detecting the intake air quantity.
- Catalysts 20 L and 20 R are provided at the lower ends of the exhaust manifolds 5 L and 5 R, respectively.
- the catalysts 20 L and 20 R clean the exhaust gases exhausted from the cylinders of the banks 12 L and 12 R, respectively.
- Air-fuel ratio sensors 9 L and 9 R are attached to the exhaust manifolds 5 L and 5 R, respectively.
- a cooling unit 40 L is provided between an exhaust port (not illustrated) of the bank 12 L and the exhaust manifold 5 L.
- a cooling unit 40 R is provided between an exhaust port (not illustrated) of the bank 12 R and the exhaust manifold 5 R.
- the cooling units 40 L and 40 R are configured such that the coolant flows around pipes of the exhaust manifolds 5 L and 5 R respectively.
- the cooling units 40 L and 40 R will be described later in detail.
- the opening degree of the throttle valve 6 is individually controlled for each of the banks 12 L and 12 R by electronic Control Units (ECUs) 7 L and 7 R, respectively. Also, the fuel quantities injected from the fuel injection valves 15 L and 15 R are individually controlled by the ECUs 7 L and 7 R, respectively.
- the ECUs 7 L and 7 R can cut fuel injected from the fuel injection valves 15 L and 15 R.
- the ECUs 7 L and 7 R correspond to an estimation portion, and a control portion, as will be described later in detail.
- the ECUs 7 L and 7 R can communicate to each other via a telecommunication line 8 . In order to control operations of the banks for which the ECUs 7 L and 7 R are responsible, the ECUs 7 L and 7 R exchange information via the telecommunication 8 to refer to information on an operating state of each bank.
- the air-fuel ratio sensors 9 L and 9 R output detection signals according to the air-fuel ratio of the exhaust gas to the ECUs 7 L and 7 R respectively.
- the ECUs 7 L and 7 R control each of the fuel injection quantities injected into the cylinders 14 L and 14 R based on the output signals from the air-fuel ratio sensors 9 L and 9 R respectively, so as to control the air-fuel ratio to be feed back.
- Such a control for feeding back the air-fuel ratio is to control the fuel injection quantity or the like such that the detected air-fuel ratio of the exhaust gas is identical to a target air-fuel ratio.
- a water temperature sensor 52 outputs detection signals according to a temperature of the coolant, as will be described later, to the ECR 7 L. Additionally, the water temperature sensor 52 is arranged at an arbitrary position on the path through which the coolant is circulated. An ignition switch 30 outputs an ON signal or an OFF signal to the ECU 7 L.
- FIG. 2 is a view of a path of the coolant.
- a radiator 72 As illustrated in FIG. 2 , a radiator 72 , an inlet 74 , a pump 76 , and the like are arranged on the path of the coolant.
- a primary path 82 circulates the coolant through the inlet 74 , the pump 76 , the engine 10 , and the radiator 72 , in this order.
- the primary path 82 circulates the coolant to the radiator 72 from a rear joint portion 19 of the engine 10 .
- a supporting path 88 circulates the coolant through the inlet 74 , the pump 76 , the engine 10 , the cooling units 40 L and 40 R, and a V bank pipe 60 , in this order.
- the supporting path 88 diverges from the rear joint portion 19 , and includes divergence paths 86 L and 86 R which circulate the coolant through the cooling units 40 L and 40 R respectively.
- the pump 76 is a mechanical pump which operates in conjunction with the revolution of the engine 10 .
- the coolant flows from the inlet 74 to the engine 10 .
- the coolant flows into a block side water jacket 11 w of the engine 10 at first, and then flows into head side water jackets 12 Lw and 12 Rw.
- the coolants discharged from the head side water jackets 12 Lw and 12 Rw join together at the rear joint portion 19 .
- the primary path 82 and the supporting path 88 are connected to the rear joint portion 19 .
- the coolant flowing through the primary path 82 flows from the rear joint portion 19 to the radiator 72 , and radiates heat in the radiator 72 .
- the cooling unit 40 L is arranged on the divergence path 86 L.
- the coolant flows through the cooling unit 40 L.
- the coolant flows through the cooling unit 40 L, thereby reducing a temperature of the exhaust gas exhausted from the cylinders 14 L of the bank 12 L.
- these arrangements are applicable to the divergence path 86 R and the cooling unit 40 R.
- FIG. 3 is a flowchart of an example of a control performed by the ECUs 7 L and 7 R.
- the ECUs 7 L and 7 R detect a coolant temperature based on the outputs from the water temperature sensor 52 (step S 1 ). Additionally, the coolant temperature may be estimated by a known method without depending on the outputs from the water temperature sensor 52 .
- the ECUs 7 L and 7 R calculate an exhaust gas temperature and an exhaust gas quantity (step S 2 ).
- the exhaust gas temperature is calculated based on a map illustrated in FIG. 4A .
- FIG. 4A is a map for calculating the exhaust gas temperature, and is stored beforehand in the ECUs 7 L and 7 R.
- the vertical axis indicates the revolution number of the engine 10
- the horizontal axis indicates the load of the engine 10 .
- the exhaust gas temperature is calculated to be higher as the revolution number and the load of the engine 10 are higher.
- the exhaust gas quantity (g/sec) is calculated based on the intake air quantity detected by the outputs from the airflow meter 18 and the air-fuel ratio detected by the outputs from the air-fuel ratio sensors 9 L and 9 R.
- the ECUs 7 L and 7 R estimate the heat quantity P of the exhaust gas (step S 3 ). Specifically, this is estimated by the following formula.
- M stands for exhaust gas quantity
- Cp stands for specific heat of exhaust gas
- Tex stands for exhaust gas temperature
- Tair stands for outside air temperature.
- the heat quantity P is calculated by substituting the exhaust gas quantity and the exhaust gas temperature calculated in step S 2 into M and Tex respectively.
- an outside air temperature may be detected by a known sensor, or estimated or calculated by a well-known method.
- the ECUs 7 L and 7 R decide whether or not the coolant temperature is higher than a decision value D 1 (step S 4 ).
- the ECUs 7 L and 7 R decide whether or not the heat quantity of the exhaust gas is higher than a decision value D 2 (step S 5 ).
- the heat quantity of the exhaust gas is one calculated in step S 3 .
- the ECUs 7 L and 7 R set a previous first counter value T 1 added with 1 as a current first counter value T 1 (step S 6 ).
- the first counter value T 1 is a value used for measuring a period while the heat quantity of the exhaust gas is higher than the decision value D 2 .
- the ECUs 7 L and 7 R decide whether the first counter value T 1 is higher than a decision value D 3 (step S 7 ).
- the ECUs 7 L and 7 R turn ON a flag for performing the idling after the ignition switch 30 is detected to be OFF (step S 8 ).
- the reason why the idling is performed after OFF of the ignition switch is detected is as follows. The pump is operated by performing the idling for a given period even after the ignition switch 30 is OFF so as to prevent boiling of the coolant caused by the heat quantities stored in the cooling units 40 L and 40 R.
- the ECUs 7 L and 7 R calculate an idling period (step S 9 ). Specifically, the ECUs 7 L and 7 R calculate an idling period corresponding to the first counter value T 1 as illustrated in FIG. 4B .
- FIG. 4B is a map for calculating the idling period. As for the map illustrated in FIG. 4B , the vertical axis indicates the idling period, and the horizontal axis indicates the first counter value T 1 . As illustrated in FIG. 4B , the idling period is set to be longer as the first counter value T 1 is larger. This is because the heat quantities stored in the cooling units 40 L and 40 R seem to be higher as the first counter value T 1 is higher.
- the idling period is set to be 30, 60, 90, and 120 (sec), respectively.
- the first counter value T 1 corresponds to a period while the heat quantity of the exhaust gas is higher than the decision value D 2 .
- the idling period is set in response to the period while the heat quantity of the exhaust gas is higher than the decision value D 2 . That is, the operating period of the pump 76 is set in response to the period while the heat quantity of the exhaust gas is higher than the decision value D 2 .
- the ECUs 7 L and 7 R decide whether or not an OFF signal is detected from the ignition switch 30 (step S 10 ).
- the ECUs 7 L and 7 R perform step S 1 again.
- the ECUs 7 L and 7 R detect an OFF signal from the ignition switch 30
- the ECUs 7 L and 7 R perform the idling (step S 11 ).
- the idling is performed, so the pump 76 is operated in conjunction with the engine 10 .
- the pump 76 is operated for a given period, and then the coolant circulates through the path. This prevents boiling of the coolant caused by the influence of the heat quantities stored in the cooling units 40 L and 40 R.
- step S 15 When the coolant temperature is lower than the decision value D 1 in step S 4 , the ECUs 7 L and 7 R turn off an idling performance flag (step S 15 ). This is because there is a little possibility that the coolant boils even after the ignition switch 30 is turned OFF in cases where the coolant temperature is low to some extent.
- the ECUs 7 L and 7 R decide whether or not the idling performance flag is ON (step S 12 ). When a negative decision is made, the ECUs 7 L and 7 R perform step S 15 . When an affirmative decision is made, the ECUs 7 L and 7 R calculate a previous second counter value T 2 added with 1 as a current second counter value T 2 (step S 13 ). The second counter value T 2 is used for measuring a period while the heat quantity of the exhaust gas is lower than the decision value D 1 .
- the ECUs 7 L and 7 R decide whether or not the second counter value T 2 is higher than a decision value D 4 (step S 14 ).
- the ECUs 7 L and 7 R perform step S 15 . This is because the heat quantities stored in the cooling units 40 R and 40 L are estimated to be low in this case.
- the ECUs 7 L and 7 R turn ON the idling flag (step S 8 ). This is because the heat quantities stored in the cooling units 40 R and 40 L are estimated to be still enough in this case.
- the second counter value T 2 corresponds to the period while the heat quantity of the exhaust gas is lower than the decision value D 2 .
- whether or not to perform the idling is decided in response to the period while the estimated heat quantity of the exhaust gas is lower than the decision value D 2 and in response to the period while the estimated heat quantity of the exhaust gas is higher than the decision value D 2 . That is, whether or not to operate the pump 76 is decided after the ignition switch 30 is turned OFF, in response to the period while the estimated heat quantity of the exhaust gas is lower than the decision value D 2 and to the period while the estimated heat quantity of the exhaust gas is higher than the decision value D 2 . This can decide whether or not to operate the pump 76 , in consideration of the driving state of the engine 10 before the ignition switch 30 is turned OFF.
- the ECUs 7 L and 7 R estimate the heat quantity of the exhaust gas, and decide whether or not to perform the idling after the ignition switch 30 is detected to be OFF in response to the estimated heat quantity. Therefore, when the heat quantity of the exhaust is high, the pump is operated after the ignition switch 30 is detected to be OFF, and then the coolant is circulated. It is thus possible to prevent boiling of the coolant caused by the heat quantities stored in the cooling units 40 L and 40 R.
- FIGS. 5 and 6 are timing charts to explain the control performed by the ECUs 7 L and 7 R. Additionally, FIGS. 5 and 6 illustrate the heat quantity P of the exhaust gas, the temperature Tc of the cooling units 40 L and 40 R, and the coolant temperature Tw. Further, the coolant temperature Tw indicates the temperature of the coolant around the cooling units 40 L and 40 R.
- FIG. 5 is the timing chart in cases where the idling is performed after the ignition switch 30 is detected to be OFF.
- the heat quantity P of the exhaust gas rises to be higher than the decision value D 2 .
- the ignition switch 30 is turned OFF in the state where the heat quantity P is higher than the decision value D 2 , the idling is performed in the engine 10 . If the temperature Tc of the cooling units 40 L and 40 R is 200 degrees Celsius at the time when the ignition switch 30 is turned OFF, the heat quantity P of the exhaust gas is drastically decreased by performing the idling, and then the temperature Tc of the cooling units 40 L and 40 R is also gradually decreased from 200 degrees Celsius.
- the pump 76 since the pump 76 is operated by performing the idling and the coolant is circulated through the path, the coolant temperature remains at about 90 degrees Celsius without being significantly changed before and after the ignition switch 30 is turned OFF. Such a manner can prevent boiling of the coolant caused by the heat quantities stored in the cooling units 40 L and 40 R.
- the operation of the pump 76 is stopped when the ignition switch 30 is turned OFF. In this case, the pump 76 is stopped, and then the coolant is not circulated. Thus, there is a possibility that boiling of the coolant remained within or around the cooling units 40 L and 40 R is caused by the heat quantities stored in the cooling units 40 L and 40 R.
- the idling is performed for a given period even after the ignition switch 30 is turned OFF. Therefore, the coolant is circulated until the heat quantities stored in the cooling units 40 L and 40 R is reduced. This can prevent the coolant from boiling.
- FIG. 6 is the timing chart in cases where the idling is not performed after the ignition switch 30 is detected to be OFF.
- the heat quantity P of the exhaust gas has been already lower than the decision value D 2 by the low-revolution and low-load driving state. For this reason, the idling is not performed in such a state. This is because the heat quantity P of the exhaust gas is reduced and so the heat quantities stored in the cooling units 40 L and 40 R are estimated to be low. Thus, the idling is not performed in such a case.
- FIG. 7 is a view of a path of the control device of the internal combustion engine of the second embodiment.
- a pump 76 a is employed in the control device of the internal combustion engine according to the second embodiment.
- the pump 76 a is an electric pump to operate based on instructions from the ECUs 7 L and 7 R. Thus, even after the engine 10 is stopped, the pump 76 a operates based on instructions from the ECUs 7 L and 7 R.
- FIG. 8 is a flowchart of an example of the control performed by the ECUs 7 L and 7 R.
- the ECUs 7 L and 7 R When the ECUs 7 L and 7 R perform steps S 1 to S 7 , the ECUs 7 L and 7 R turn ON an execution flag for operating the pump 76 a after the ignition switch 30 is detected to be OFF (step S 8 a).
- an operation period of the pump 76 a is calculated (step S 9 a). Additionally, the operation period of the pump 76 a is calculated based on the first counter value T 1 , like the first embodiment.
- the ECUs 7 L and 7 R stop the engine 10 and operate the pump 76 a (step S 11 a).
- the pump 76 a is operated for a given period after the ignition switch 30 is turned OFF, thereby preventing boiling of the coolant caused by the heat quantities stored in the cooling units 40 L and 40 R. Additionally, when a negative decision is made in step S 7 or an affirmative decision is made in step S 14 , the execution flag for operating the pump 76 a is turned OFF after the ignition switch 30 is turned OFF (step S 15 a).
- FIG. 9 is an explanatory view of the path of the coolant of the control unit of the internal combustion engine according to the third embodiment.
- the path of the coolant includes: the primary path 82 passing through the engine 10 ; and a secondary path passing through the cooling units 40 L and 40 R and connected in parallel with the primary path 82 .
- a control valve 78 is provided between the pump 76 a and the engine 10 on the primary path 82 .
- the control valve 78 can control the flow rate of the coolant passing via the primary path 82 in response to instructions from the ECUs 7 L and 7 R.
- the control valve 78 can maintain its given opening degree in response to instructions from the ECUs 7 L and 7 R.
- FIG. 10 is a flowchart of an example of the control performed by the ECUs 7 L and 7 R.
- the ECUs 7 L and 7 R When the ECUs 7 L and 7 R perform steps S 1 to S 10 and then the ignition switch 30 is detected to be OFF, the ECUs 7 L and 7 R operate the pump 76 a (step S 11 a), and in addition, close the control valve 78 (step S 11 b). Therefore, the coolant does not flow through the engine 10 , whereas the coolant flows through the secondary path 86 . This increases the flow rate of the coolant flowing through the cooling units 40 L and 40 R. Hence, the cooling units 40 L and 40 R are cooled for a short period with the large amount of the coolant flowing therehrough.
- the flow rate of the coolant flowing through the engine 10 may be suppressed by controlling the opening degree of the control valve 78 to be a given degree, instead of by fully closing the control valve 78 .
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Combined Controls Of Internal Combustion Engines (AREA)
- Exhaust Gas After Treatment (AREA)
Abstract
A control device for an internal combustion engine according to an embodiment includes: cooling units arranged on a path where a coolant is circulated, and cooling an exhaust gas of the internal combustion engine with the coolant flowing through the cooling units; a pump circulating the coolant; and ECUs estimating a heat quantity of the exhaust gas and deciding whether or not to operate the pump after an ignition switch is detected to be OFF in response to the estimated heat quantity of the exhaust gas.
Description
- The present invention relates to a control device for an internal combustion engine.
- There is a cooling unit for cooling exhaust gases of an internal combustion engine. There is the cooling unit which is provided between an exhaust port and an exhaust manifold or which is provided around the exhaust manifold (See Patent Document 1). The exhaust gases are cooled with coolant water flowing through the cooling unit.
- [Patent Document 1] Japanese Patent Application Publication No. 63-208607.
- Such a cooling unit is arranged on a path through which a coolant flows. The coolant is circulated through the path by a pump. Also, such a cooling unit stores a part of the heat quantity of the exhaust gas. When the internal combustion engine is stopped, the pump is stopped and then the coolant is not circulated. For this reason, the heat quantity stored in the cooling unit is transmitted to the coolant, and then the coolant might boil.
- It is an object of the present invention to provide a control device of an internal combustion engine suppressing boiling of a coolant.
- The above object is achieved by a control device for an internal combustion engine, the control device including: a cooling unit arranged on a path where a coolant is circulated, and cooling an exhaust gas of the internal combustion engine with the coolant flowing through the cooling unit; a pump circulating the coolant; an estimation portion estimating a heat quantity of the exhaust gas, and a control portion deciding whether or not to operate the pump after an ignition switch is detected to be OFF, in response to the estimated heat quantity of the exhaust gas. With these arrangements, for example, in even cases where the heat quantity of the exhaust is high and the ignition switch is detected to be OFF, the pump is operated to circulate the coolant, thereby preventing boiling of the coolant caused by the heat quantity stored in the cooling unit.
- According to the present invention, there is provided a control device of an internal combustion engine suppressing boiling of a coolant.
-
FIG. 1 is an explanatory view of a control device for an internal combustion engine; -
FIG. 2 is a view of a path of a coolant; -
FIG. 3 is a flowchart of an example of a control performed by an ECU; -
FIG. 4A is a map for calculating an exhaust gas temperature, andFIG. 4B is a map for calculating an idling period; -
FIG. 5 is a timing chart to explain the control performed by the ECU; -
FIG. 6 is a timing chart to explain the control performed by the ECU; -
FIG. 7 is a view of a path of the coolant in the cooling device for the internal combustion engine according to a second embodiment; -
FIG. 8 is a flowchart of an example of the control performed by the ECU; -
FIG. 9 is an explanatory view of a path of the coolant in the cooling device for the internal combustion engine according to a third embodiment; and -
FIG. 10 is a flowchart of an example of the control performed by the ECU. - Embodiments will be described below with reference to the drawings.
-
FIG. 1 is an explanatory view of a control device for an internal combustion engine. Anengine 10 has a pair ofbanks banks engine 10 is a so-called V-type engine. Thebank 12L has a cylinder group including threecylinders 14L. Likewise, thebank 12R hascylinders 14R. - Also, the
bank 12L is provided withfuel injection valves 15L injecting fuel directly into thecylinders 14L. Likewise, thebank 12R is provided withfuel injection valves 15R injecting fuel directly into thecylinders 14R. Anintake path 4L and anexhaust manifold 5L are connected to thebank 12L. Anintake path 4R and anexhaust manifold 5R are connected to thebank 12R. Theintake paths throttle valve 6 for adjusting intake air quantity and an airflow meter for detecting the intake air quantity. -
Catalysts exhaust manifolds catalysts banks fuel ratio sensors exhaust manifolds - A
cooling unit 40L is provided between an exhaust port (not illustrated) of thebank 12L and theexhaust manifold 5L. Likewise, acooling unit 40R is provided between an exhaust port (not illustrated) of thebank 12R and theexhaust manifold 5R. - The
cooling units exhaust manifolds cooling units - The opening degree of the
throttle valve 6 is individually controlled for each of thebanks fuel injection valves ECUs ECUs fuel injection valves ECUs ECUs telecommunication line 8. In order to control operations of the banks for which theECUs ECUs telecommunication 8 to refer to information on an operating state of each bank. - Also, the air-
fuel ratio sensors ECUs ECUs cylinders fuel ratio sensors - A
water temperature sensor 52 outputs detection signals according to a temperature of the coolant, as will be described later, to theECR 7L. Additionally, thewater temperature sensor 52 is arranged at an arbitrary position on the path through which the coolant is circulated. Anignition switch 30 outputs an ON signal or an OFF signal to theECU 7L. -
FIG. 2 is a view of a path of the coolant. As illustrated inFIG. 2 , aradiator 72, aninlet 74, apump 76, and the like are arranged on the path of the coolant. Aprimary path 82 circulates the coolant through theinlet 74, thepump 76, theengine 10, and theradiator 72, in this order. Theprimary path 82 circulates the coolant to theradiator 72 from a rearjoint portion 19 of theengine 10. A supportingpath 88 circulates the coolant through theinlet 74, thepump 76, theengine 10, the coolingunits V bank pipe 60, in this order. The supportingpath 88 diverges from the rearjoint portion 19, and includesdivergence paths units - The
pump 76 is a mechanical pump which operates in conjunction with the revolution of theengine 10. The coolant flows from theinlet 74 to theengine 10. The coolant flows into a blockside water jacket 11w of theengine 10 at first, and then flows into head side water jackets 12Lw and 12Rw. The coolants discharged from the head side water jackets 12Lw and 12Rw join together at the rearjoint portion 19. Theprimary path 82 and the supportingpath 88 are connected to the rearjoint portion 19. The coolant flowing through theprimary path 82 flows from the rearjoint portion 19 to theradiator 72, and radiates heat in theradiator 72. - The
cooling unit 40L is arranged on thedivergence path 86L. The coolant flows through thecooling unit 40L. The coolant flows through thecooling unit 40L, thereby reducing a temperature of the exhaust gas exhausted from thecylinders 14L of thebank 12L. Likewise, these arrangements are applicable to thedivergence path 86R and thecooling unit 40R. -
FIG. 3 is a flowchart of an example of a control performed by theECUs ECUs water temperature sensor 52. - Next, the
ECUs FIG. 4A .FIG. 4A is a map for calculating the exhaust gas temperature, and is stored beforehand in theECUs FIG. 4A , the vertical axis indicates the revolution number of theengine 10, and the horizontal axis indicates the load of theengine 10. The exhaust gas temperature is calculated to be higher as the revolution number and the load of theengine 10 are higher. - Also, the exhaust gas quantity (g/sec) is calculated based on the intake air quantity detected by the outputs from the
airflow meter 18 and the air-fuel ratio detected by the outputs from the air-fuel ratio sensors - Next, the
ECUs -
P=M×Cp×(Tex−Tair) (1) - M stands for exhaust gas quantity, Cp stands for specific heat of exhaust gas, Tex stands for exhaust gas temperature, and Tair stands for outside air temperature. The heat quantity P is calculated by substituting the exhaust gas quantity and the exhaust gas temperature calculated in step S2 into M and Tex respectively. Also, an outside air temperature may be detected by a known sensor, or estimated or calculated by a well-known method.
- Next, the
ECUs ECUs ECUs - Next, the
ECUs ECUs ignition switch 30 is detected to be OFF (step S8). The reason why the idling is performed after OFF of the ignition switch is detected is as follows. The pump is operated by performing the idling for a given period even after theignition switch 30 is OFF so as to prevent boiling of the coolant caused by the heat quantities stored in thecooling units - Next, the
ECUs ECUs FIG. 4B .FIG. 4B is a map for calculating the idling period. As for the map illustrated inFIG. 4B , the vertical axis indicates the idling period, and the horizontal axis indicates the first counter value T1. As illustrated inFIG. 4B , the idling period is set to be longer as the first counter value T1 is larger. This is because the heat quantities stored in thecooling units pump 76 is set in response to the period while the heat quantity of the exhaust gas is higher than the decision value D2. - Next, the
ECUs ECUs ECUs ignition switch 30, theECUs pump 76 is operated in conjunction with theengine 10. Thus, even if theignition switch 30 is turned OFF, thepump 76 is operated for a given period, and then the coolant circulates through the path. This prevents boiling of the coolant caused by the influence of the heat quantities stored in thecooling units - When the coolant temperature is lower than the decision value D1 in step S4, the
ECUs ignition switch 30 is turned OFF in cases where the coolant temperature is low to some extent. - When the heat quantity of the exhaust gas is lower than the decision value D2 in step S5, the
ECUs ECUs ECUs - The
ECUs ECUs cooling units ECUs cooling units pump 76 is decided after theignition switch 30 is turned OFF, in response to the period while the estimated heat quantity of the exhaust gas is lower than the decision value D2 and to the period while the estimated heat quantity of the exhaust gas is higher than the decision value D2. This can decide whether or not to operate thepump 76, in consideration of the driving state of theengine 10 before theignition switch 30 is turned OFF. - As mentioned above, the
ECUs ignition switch 30 is detected to be OFF in response to the estimated heat quantity. Therefore, when the heat quantity of the exhaust is high, the pump is operated after theignition switch 30 is detected to be OFF, and then the coolant is circulated. It is thus possible to prevent boiling of the coolant caused by the heat quantities stored in thecooling units - Next, the control performed by the
ECUs FIGS. 5 and 6 are timing charts to explain the control performed by theECUs FIGS. 5 and 6 illustrate the heat quantity P of the exhaust gas, the temperature Tc of thecooling units units -
FIG. 5 is the timing chart in cases where the idling is performed after theignition switch 30 is detected to be OFF. For example, when a vehicle runs up a slope and is continuously driven in the high-revolution and high-load state, the heat quantity P of the exhaust gas rises to be higher than the decision value D2. When theignition switch 30 is turned OFF in the state where the heat quantity P is higher than the decision value D2, the idling is performed in theengine 10. If the temperature Tc of thecooling units ignition switch 30 is turned OFF, the heat quantity P of the exhaust gas is drastically decreased by performing the idling, and then the temperature Tc of thecooling units pump 76 is operated by performing the idling and the coolant is circulated through the path, the coolant temperature remains at about 90 degrees Celsius without being significantly changed before and after theignition switch 30 is turned OFF. Such a manner can prevent boiling of the coolant caused by the heat quantities stored in thecooling units - It is supposed that the operation of the
pump 76 is stopped when theignition switch 30 is turned OFF. In this case, thepump 76 is stopped, and then the coolant is not circulated. Thus, there is a possibility that boiling of the coolant remained within or around the coolingunits cooling units ignition switch 30 is turned OFF. Therefore, the coolant is circulated until the heat quantities stored in thecooling units - Next, a case where the idling is not performed will be described.
FIG. 6 is the timing chart in cases where the idling is not performed after theignition switch 30 is detected to be OFF. As illustrated inFIG. 6 , for example, in cases a vehicle is in a low-revolution and low-load driving state and theignition switch 30 is turned OFF after the vehicle is in a high-revolution and high-load driving state, the heat quantity P of the exhaust gas has been already lower than the decision value D2 by the low-revolution and low-load driving state. For this reason, the idling is not performed in such a state. This is because the heat quantity P of the exhaust gas is reduced and so the heat quantities stored in thecooling units - Next, the control device for the internal combustion engine according to a second embodiment will be described.
FIG. 7 is a view of a path of the control device of the internal combustion engine of the second embodiment. Apump 76 a is employed in the control device of the internal combustion engine according to the second embodiment. Thepump 76 a is an electric pump to operate based on instructions from theECUs engine 10 is stopped, thepump 76 a operates based on instructions from theECUs - Next, the control performed by the
ECUs FIG. 8 is a flowchart of an example of the control performed by theECUs ECUs ECUs pump 76 a after theignition switch 30 is detected to be OFF (step S8a). Next, an operation period of thepump 76 a is calculated (step S9a). Additionally, the operation period of thepump 76 a is calculated based on the first counter value T1, like the first embodiment. When theignition switch 30 is detected to be OFF, theECUs engine 10 and operate thepump 76 a (step S11a). - In such a way, the
pump 76 a is operated for a given period after theignition switch 30 is turned OFF, thereby preventing boiling of the coolant caused by the heat quantities stored in thecooling units pump 76 a is turned OFF after theignition switch 30 is turned OFF (step S15a). - Next, the control device of the internal combustion engine according to a third embodiment will be described.
FIG. 9 is an explanatory view of the path of the coolant of the control unit of the internal combustion engine according to the third embodiment. As illustrated inFIG. 9 , the path of the coolant includes: theprimary path 82 passing through theengine 10; and a secondary path passing through the coolingunits primary path 82. Also, a control valve 78 is provided between thepump 76 a and theengine 10 on theprimary path 82. The control valve 78 can control the flow rate of the coolant passing via theprimary path 82 in response to instructions from theECUs ECUs -
FIG. 10 is a flowchart of an example of the control performed by theECUs ECUs ignition switch 30 is detected to be OFF, theECUs pump 76 a (step S11a), and in addition, close the control valve 78 (step S11b). Therefore, the coolant does not flow through theengine 10, whereas the coolant flows through thesecondary path 86. This increases the flow rate of the coolant flowing through the coolingunits units cooling units engine 10 may be suppressed by controlling the opening degree of the control valve 78 to be a given degree, instead of by fully closing the control valve 78. - While the exemplary embodiments of the present invention have been illustrated in detail, the present invention is not limited to the above-mentioned embodiments, and other embodiments, variations and modifications may be made without departing from the scope of the present invention.
Claims (6)
1. A control device for an internal combustion engine, comprising:
a cooling unit arranged on a path where a coolant is circulated, and cooling an exhaust gas of the internal combustion engine with the coolant flowing through the cooling unit;
a pump circulating the coolant;
an estimation portion estimating a heat quantity of the exhaust gas, and
a control portion deciding whether or not to operate the pump after an ignition switch is detected to be OFF, in response to the estimated heat quantity of the exhaust gas
wherein the control portion decides whether or not to operate the pump after the ignition switch is detected to be OFF, in response to a period while the estimated heat quantity of the exhaust gas is higher than a decision value and in response to a period while the estimated heat quantity of the exhaust gas is lower than the decision value.
2. The control device for the internal combustion engine of claim 1 , wherein the pump is a mechanical pump in conjunction with the internal combustion engine, and the control portion operates the pump by performing idling after the ignition switch is detected to be OFF.
3. The control device for the internal combustion engine of claim 1 , wherein the pump is an electric pump operated in response to an instruction from the control portion.
4. The control device for the internal combustion engine of claim 1 , wherein
the path includes: a primary path passing through the internal combustion engine; and a secondary path passing through the cooling unit and connected in parallel with the primary path,
a control valve is provided for controlling a flow rate of the coolant flowing through the primary path, and
the control portion suppresses a flow rate of the coolant flowing through the primary path by controlling the control valve after the ignition switch is detected to be OFF.
5. The control device for the internal combustion engine of claim 1 , wherein the control portion sets an operating period of the pump in response to a period while the estimated heat quantity of the exhaust gas is higher than a decision value.
6. (canceled)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/JP2009/057670 WO2010119545A1 (en) | 2009-04-16 | 2009-04-16 | Control device for internal combustion engine |
Publications (1)
Publication Number | Publication Date |
---|---|
US20120035829A1 true US20120035829A1 (en) | 2012-02-09 |
Family
ID=42982228
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/264,087 Abandoned US20120035829A1 (en) | 2009-04-16 | 2009-04-16 | Control device for internal combustion engine |
Country Status (4)
Country | Link |
---|---|
US (1) | US20120035829A1 (en) |
JP (1) | JP5099260B2 (en) |
CN (1) | CN102395767B (en) |
WO (1) | WO2010119545A1 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20160245196A1 (en) * | 2015-02-19 | 2016-08-25 | Toyota Jidosha Kabushiki Kaisha | Control device of vehicle |
US10662894B2 (en) | 2016-02-04 | 2020-05-26 | Scania Cv Ab | Method for controlling the temperature of a waste heat recovery system and such a waste heat recovery system |
US10662820B2 (en) | 2016-02-04 | 2020-05-26 | Scania Cv Ab | Method for controlling a waste heat recovery system and such a waste heat recovery system |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102009052151B3 (en) * | 2009-11-06 | 2011-05-05 | Mtu Friedrichshafen Gmbh | Cooling system of an internal combustion engine |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4098236A (en) * | 1976-10-29 | 1978-07-04 | Toyota Jidosha Kogyo Kabushiki Kaisha | Device for supplying fuel to an internal combustion engine |
US6321697B1 (en) * | 1999-06-07 | 2001-11-27 | Mitsubishi Heavy Industries, Ltd. | Cooling apparatus for vehicular engine |
JP2008115774A (en) * | 2006-11-06 | 2008-05-22 | Aisin Seiki Co Ltd | Engine cooling apparatus |
US20100236502A1 (en) * | 2007-11-21 | 2010-09-23 | Toyota Jidosha Kabushiki Kaisha | Vehicle cooling controller and cooling control method |
US20120035830A1 (en) * | 2009-04-16 | 2012-02-09 | Toyota Jidosha Kabushiki Kaisha | Control device for internal combustion engine |
US8387572B2 (en) * | 2009-12-04 | 2013-03-05 | Ford Global Technologies, Llc | Auxiliary pump scheme for a cooling system in a hybrid-electric vehicle |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2005090236A (en) * | 2003-09-12 | 2005-04-07 | Mitsubishi Motors Corp | Cooling device for internal combustion engine |
JP4119833B2 (en) * | 2003-12-25 | 2008-07-16 | 本田技研工業株式会社 | Exhaust manifold integrated engine cooling structure |
JP4661767B2 (en) * | 2006-10-31 | 2011-03-30 | 日産自動車株式会社 | Failure diagnosis device for engine cooling system |
JP4845803B2 (en) * | 2007-05-01 | 2011-12-28 | トヨタ自動車株式会社 | Cooling device for internal combustion engine |
JP4575934B2 (en) * | 2007-06-19 | 2010-11-04 | 本田技研工業株式会社 | Exhaust manifold cooling system |
-
2009
- 2009-04-16 WO PCT/JP2009/057670 patent/WO2010119545A1/en active Application Filing
- 2009-04-16 CN CN200980158776.3A patent/CN102395767B/en not_active Expired - Fee Related
- 2009-04-16 US US13/264,087 patent/US20120035829A1/en not_active Abandoned
- 2009-04-16 JP JP2011509144A patent/JP5099260B2/en not_active Expired - Fee Related
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4098236A (en) * | 1976-10-29 | 1978-07-04 | Toyota Jidosha Kogyo Kabushiki Kaisha | Device for supplying fuel to an internal combustion engine |
US6321697B1 (en) * | 1999-06-07 | 2001-11-27 | Mitsubishi Heavy Industries, Ltd. | Cooling apparatus for vehicular engine |
JP2008115774A (en) * | 2006-11-06 | 2008-05-22 | Aisin Seiki Co Ltd | Engine cooling apparatus |
US20100236502A1 (en) * | 2007-11-21 | 2010-09-23 | Toyota Jidosha Kabushiki Kaisha | Vehicle cooling controller and cooling control method |
US20120035830A1 (en) * | 2009-04-16 | 2012-02-09 | Toyota Jidosha Kabushiki Kaisha | Control device for internal combustion engine |
US8387572B2 (en) * | 2009-12-04 | 2013-03-05 | Ford Global Technologies, Llc | Auxiliary pump scheme for a cooling system in a hybrid-electric vehicle |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20160245196A1 (en) * | 2015-02-19 | 2016-08-25 | Toyota Jidosha Kabushiki Kaisha | Control device of vehicle |
US9856801B2 (en) * | 2015-02-19 | 2018-01-02 | Toyota Jidosha Kabushiki Kaisha | Control device of vehicle |
US10662894B2 (en) | 2016-02-04 | 2020-05-26 | Scania Cv Ab | Method for controlling the temperature of a waste heat recovery system and such a waste heat recovery system |
US10662820B2 (en) | 2016-02-04 | 2020-05-26 | Scania Cv Ab | Method for controlling a waste heat recovery system and such a waste heat recovery system |
Also Published As
Publication number | Publication date |
---|---|
WO2010119545A1 (en) | 2010-10-21 |
JP5099260B2 (en) | 2012-12-19 |
JPWO2010119545A1 (en) | 2012-10-22 |
CN102395767B (en) | 2014-03-26 |
CN102395767A (en) | 2012-03-28 |
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Owner name: TOYOTA JIDOSHA KABUSHIKI KAISHA, JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:MITANI, SHINICHI;HIROOKA, SHIGEMASA;TSUNOOKA, TAKASHI;AND OTHERS;REEL/FRAME:027064/0730 Effective date: 20110621 |
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