US20120047893A1 - Engine cooling device - Google Patents

Engine cooling device Download PDF

Info

Publication number
US20120047893A1
US20120047893A1 US13/201,717 US200913201717A US2012047893A1 US 20120047893 A1 US20120047893 A1 US 20120047893A1 US 200913201717 A US200913201717 A US 200913201717A US 2012047893 A1 US2012047893 A1 US 2012047893A1
Authority
US
United States
Prior art keywords
flow rate
engine
coolant
cooling
water
Prior art date
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
Application number
US13/201,717
Other languages
English (en)
Inventor
Koichi Hoshi
Yoshihisa Shinoda
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toyota Motor Corp
Original Assignee
Toyota Motor Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Toyota Motor Corp filed Critical Toyota Motor Corp
Assigned to TOYOTA JIDOSHA KABUSHIKI KAISHA reassignment TOYOTA JIDOSHA KABUSHIKI KAISHA ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: HOSHI, KOICHI, SHINODA, YOSHIHISA
Publication of US20120047893A1 publication Critical patent/US20120047893A1/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • 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
    • F01P7/00—Controlling of coolant flow
    • F01P7/14—Controlling of coolant flow the coolant being liquid
    • F01P7/16—Controlling of coolant flow the coolant being liquid by thermostatic control
    • F01P7/164—Controlling of coolant flow the coolant being liquid by thermostatic control by varying pump speed
    • 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
    • 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
    • F01P2060/08—Cabin heater
    • 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
    • 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 an engine cooling device, and more particularly, relates to an engine cooling device provided with an exhaust system cooling means that cools an exhaust system of an engine with flowing coolant.
  • Patent Document 1 discloses an exhaust manifold device provided with a water jacket formed around an exhaust manifold, and a water injection means that sprays water to the water jacket.
  • Patent Document 2 discloses a cooling control device of internal combustion engine provided with a flow rate control valve that can change the supply ratio of cooling medium to a number of cooling units. More specifically, Patent Document 2 discloses a cooling control device of internal combustion engine where flow rate control valves are provided to respective cooling water paths that guide cooling water to respective cooling units such as exhaust ports and the like.
  • a coolant flowing through the engine body is generally pumped by the mechanical water pump which is driven by the output power of the engine. Therefore, when the coolant flowing through the engine body is shared, it is reasonable to use a mechanical water pump as the coolant pumping device in terms of cost.
  • a coolant flowing through the engine body is generally cooled by a cooling device (e.g. radiator).
  • the coolant temperature at the exit side of the engine body or at the flowing path just after flowing through the engine body is detected as the coolant temperature in the engine body (hereinafter, referred to as an engine coolant temperature).
  • the engine coolant temperature described above does not represent a coolant temperature in the exhaust system cooling means (hereinafter, referred to as the exhaust system coolant temperature). More specifically, as illustrated in FIG. 21 , there is a tendency that the exhaust system coolant temperature is normally greater than the engine coolant temperature. This is because the size of the exhaust system cooling means is normally smaller than that of the engine body, and the heat capacity of the exhaust system cooling means is smaller than that of the engine body. Therefore, in this case, there is a possibility that the coolant is overheated or boiled in the exhaust system cooling means. In other words, it is difficult to know the overheat or boiling of the coolant in the exhaust system cooling means from the engine coolant temperature.
  • the engine coolant temperature is a certain degree higher than the exhaust system coolant temperature. Therefore, in regard to this point, it is considered that it is only necessary to set the engine coolant temperature to the one which is a certain degree higher than the temperature actually detected.
  • the discharge rate of the mechanical water pump generally rises and falls in proportion to the rotation number of the engine. Therefore, when the operation state of the engine is high-rotation/high-load, the flow rate of the coolant in the exhaust system cooling means becomes large.
  • the intake air flow rate is large and the calorific value of the engine becomes large in this case, the received calorie value that the exhaust system cooling means receives from the exhaust gas increases. Therefore, in this case, the heat is kept in the wall that forms the flow path through which the exhaust gas flows, and the wall is heated to a high temperature as a result.
  • the present invention was made in view of the above problems, and has an object of providing an engine cooling device capable of preventing or suppressing an overheat or boiling of a coolant in an exhaust system cooling means when the exhaust system cooling means that cools an exhaust system of the engine with the shared coolant flowing through an engine body is provided.
  • an engine cooling device including: a coolant pumping device that pumps a shared coolant to a plurality of coolant circulation paths; an engine of which an engine body is mounted in at least one of the plurality of coolant circulation paths; an exhaust system cooling means which is mounted in at least one of the plurality of coolant circulation paths, of which a heat capacity is smaller than that of the engine body, and which cools an exhaust system of the engine by a flowing coolant; a cooling device that is mounted in at least one of the plurality of coolant circulation paths, and cools a flowing coolant; and a flow rate determination means that determines a flow rate of a coolant allowed to flow through the exhaust system cooling means based on an intake air flow rate of the engine.
  • the present invention is an engine cooling device including: a coolant pumping device that pumps a shared coolant to a plurality of coolant circulation paths; an engine of which an engine body is mounted in at least one of the plurality of coolant circulation paths; an exhaust system cooling means which is mounted in at least one of the plurality of coolant circulation paths and cools an exhaust system of the engine by a flowing coolant, and of which a heat capacity is smaller than that of the engine body; a cooling device that is mounted in at least one of the plurality of coolant circulation paths and cools a flowing coolant; and a flow rate determination means that determines a flow rate of a coolant allowed to flow through the exhaust system cooling means based on a received heat amount that a coolant receives from an exhaust in the exhaust system cooling means.
  • the present invention has a configuration further including: an estimation means that estimates a temperature of a wall, which forms a flow path through which an exhaust gas flows, of the exhaust system cooling means; and a correction means that corrects a flow rate of a coolant determined by the flow rate determination means based on the estimation.
  • the present invention it is possible to prevent or suppress the overheat or boiling of a coolant in the exhaust system cooling means when the exhaust system cooling means that cools an exhaust system of an engine with a shared coolant flowing through the engine body.
  • FIG. 1 is a diagram schematically illustrating an engine cooling device (hereinafter, referred to as a cooling device) 100 A in accordance with a first embodiment, where pipes forming a cooling water circulation path at a cooling time when a valve of a thermostat 60 is closed are illustrated by dashed lines, pipes forming a cooling water circulation path at a warming time when the valve of the thermostat 60 is opened are illustrated with solid lines, and a flowing direction of cooling water W is illustrated by arrows (this is also applied to FIG. 5 through FIG. 10 );
  • FIG. 2 is a diagram schematically illustrating a water-cooled exhaust manifold 30 ;
  • FIG. 3 is a diagram illustrating flow characteristics of cooling water W flowing through the water-cooled exhaust manifold 30 ;
  • FIG. 4 is a diagram schematically illustrating a flow rate changing structure 70 , where the dashed line illustrates a state where an idler pulley 74 pushes a belt 73 from a state illustrated with solid lines;
  • FIG. 5 is a diagram illustrating a first cooling water circulation path 81 ;
  • FIG. 6 is a diagram illustrating a second cooling water circulation path 82 ;
  • FIG. 7 is a diagram illustrating a third cooling water circulation path 83 ;
  • FIG. 8 is a diagram illustrating a fourth cooling water circulation path 84 ;
  • FIG. 9 is a diagram illustrating a fifth cooling water circulation path 85 ;
  • FIG. 10 is a diagram illustrating a sixth cooling water circulation path 86 ;
  • FIG. 11 is a diagram schematically illustrating a practical configuration of an ECU (Electronic Control Unit) 1 A;
  • FIG. 12 is a diagram illustrating relationship between (ethw+etha) ⁇ NE/100 ⁇ GA and an actual cooling loss Qw, where R 2 is a value indicating a degree of correlation, and the degree of correlation becomes high as R 2 is closer to 1 (this is also applied to FIG. 14 );
  • FIG. 13 is a diagram illustrating an operation of the ECU 1 A with a flowchart
  • FIG. 14 is a diagram illustrating a relationship between the intake air flow rate GA and the actual cooling loss Qw;
  • FIG. 15 is a diagram schematically illustrating a map data of flow rate correction amount set according to an accumulated amount of intake air flow rate ⁇ GA;
  • FIG. 16 is a flowchart illustrating an operation of an ECU 1 B
  • FIG. 17 illustrates a timing chart according to the operation of the ECU 1 B
  • FIG. 18 is a timing chart to explain the concept of the flow rate control by the ECU 1 B, where the solid line indicates a case where the operation state of the engine 20 moves from the high-rotation/high-load operation state to the low-rotation/non-high-load operation state, and the dashed line indicates a case where the operation state of the engine 20 moves from the high-rotation/high-load operation state to the low-rotation/high-load operation state;
  • FIG. 19 is a diagram unifying results of measurements of the water temperature inside the water-cooled exhaust manifold 30 and the observation of the cooling water W inside the water-cooled exhaust manifold 30 according to the intake air flow rate GA by visualization by providing the window to the water-cooled exhaust manifold 30 ;
  • FIG. 20 is a diagram schematically illustrating a variable water pump pulley 76 and a belt 73 B, more specifically, FIG. 20( a ) illustrates the pulley 76 in a state where each pulley member 76 a contacts thereto, and FIG. 20( b ) illustrates the pulley 76 in a state where pulley members 76 a are apart from each other; and
  • FIG. 21 is a diagram illustrating changes of the engine coolant temperature and the exhaust system coolant temperature after starting the cooling of the engine, together with the vehicle speed, the rotation number of engine and a throttle opening degree.
  • the cooling device 100 A is provided with an ECU 1 A, a water pump 10 , an engine 20 , a water-cooled exhaust manifold 30 , a heater core 40 , a radiator 50 , and a thermostat 60 .
  • the water pump 10 is mounted in the engine 20 .
  • the water pump 10 is a mechanical pump driven by the output power of the engine 20 , and pumps the cooling water W which is a coolant.
  • the discharge rate of the water pump 10 rises and falls in proportion to the rotation number NE of the engine 20 .
  • the engine 20 includes an engine body 21 .
  • the engine body 21 is composed of cylinder heads and cylinder blocks not illustrated.
  • a water jacket 22 , a bypass path 23 , and a communication path 24 are formed in the engine body 21 .
  • the cooling water W flows through the water jacket 22 , and the cooling water W flowing through the water jacket 22 cools the engine body 21 .
  • the bypass path 23 flows the cooling water W from the water jacket 22 to the thermostat 60 .
  • the bypass path 23 connects the exit of the water jacket 22 and the outside of it.
  • the communication path 24 connects the entrance of the bypass path 23 and the outside of it.
  • the engine body 21 is provided with a water temperature sensor 91 that detects a cooling water temperature THW which is the temperature of the cooling water W, and an engine rotation number sensor 92 used to detects a rotation number NE of the engine 20 .
  • the water temperature sensor 91 is located so as to detect the cooling water temperature THW at the exit of the water jacket 22 .
  • the water-cooled exhaust manifold 30 is mounted in the engine body 21 .
  • the water-cooled exhaust manifold 30 merges exhaust gasses exhausted from cylinders of the engine 20 .
  • the water-cooled exhaust manifold 30 includes an external wall 302 that wholly houses exhaust pipes 301 .
  • the external wall 302 forms cooling water flow paths between exhaust pipes 301 and the external wall 302 .
  • the cooling water W is supplied to the cooling water flow path from a cooling water inlet 303 , the cooling water W is discharged from the cooling water flow path via cooling water outlets 304 .
  • the flow rate of the cooling water W flowing through the water-cooled exhaust manifold 30 increases or decreases in proportion to the rotation number NE of the engine 20 (see FIG. 3 ).
  • the water-cooled exhaust manifold 30 corresponds to the exhaust system cooling means
  • exhaust pipes 301 correspond to a wall that forms a flow path through which the exhaust gas flows.
  • the heater core 40 executes a heat transfer between the cooling water W and the air.
  • the heater core 40 is utilized in an air-conditioning unit not illustrated.
  • the air-conditioning unit functions as a heating apparatus by sending the air warmed by the heater core 40 into the vehicle interior of the car.
  • the radiator 50 promotes the heat release from the flowing cooling water W by the traveling wind or the wind from the electric fan not illustrated, and cools the cooling water W.
  • the radiator 50 corresponds to a cooling device.
  • the thermostat 60 operates so as to control the flow of the cooling water W by closing a valve during cooling and by opening a valve during warming.
  • the cooling device 100 A is provided with the flow rate changing structure 70 illustrated in FIG. 4 .
  • the flow rate changing structure 70 enables the control of the rotation number of the water pump 10 according to the intake air flow rate GA, the load factor of the engine 20 , and the pressure of the intake pipe for example.
  • the flow rate changing structure 70 changes the flow rate of the cooling water W flowing through the water-cooled exhaust manifold 30 by enabling the control of the rotation number of the water pump 10 .
  • the flow rate changing structure 70 is provided with a crank pulley 71 , a water pump pulley 72 , a belt 73 , an idler pulley 74 , and an actuator 75 .
  • the pulley 71 is linked to a crankshaft of the engine 20 not illustrated.
  • the pulley 72 is linked to a rotating shaft of the water pump 10 .
  • the pulley 72 has a frustum shape, and its diameter is gradually reduced from one end to another end in an axial direction.
  • the belt 73 has a ring shape, and is looped around pulleys 71 and 72 .
  • a home position of the belt 73 on the pulley 72 is a one-end side.
  • the pulley 74 is provided so as to contact with the belt 73 between pulleys 71 and 72 .
  • the pulley 74 is connected to the actuator 75 .
  • the actuator 75 is provided so as to drive the pulley 74 along a direction in which the belt 73 can be pressed.
  • a stepping motor to which a direct acting mechanism is combined can be used as the actuator 75 .
  • the operation of the flow rate changing structure 70 is as follows. During the operation of the engine 20 , the pulley 71 rotates in conjunction with the crankshaft. The rotation of the pulley 71 is transmitted to the pulley 72 via the belt 73 . Then, when the pulley 72 rotates, the water pump 10 is driven accordingly. At this time, the water pump 10 pumps the cooling water W at the discharge rate according to the rotation number NE.
  • the actuator 75 drives the pulley 74 , and presses the pulley 74 against the belt 73 , the tension of the belt 73 increases.
  • the belt 73 slides from the one-end side to the other-end side of which the diameter is smaller on the pulley 72 . According to this, the diameter of the pulley 72 corresponding to the belt 73 is reduced. Therefore, the rotation of the water pump 10 is increased, and the discharge rate is increased.
  • the discharge rate of the water pump 10 may be decreased by operating the actuator 75 inversely.
  • the cooling device 100 A includes first through sixth cooling water circulation paths 81 through 86 corresponding to a plurality of cooling water circulation paths as illustrated in FIG. 5 through FIG. 10 .
  • First, second and third cooling water circulation paths 81 , 82 and 83 are circulation paths where the flow of the cooling water W is allowed when the thermostat 60 closes.
  • Fourth, fifth and sixth cooling water circulation paths 84 , 85 and 86 are circulation paths where the flow of the cooling water W is allowed when the thermostat 60 opens. More particularly, the water pump 10 pumps the cooling water W shared in these cooling water circulation paths 81 through 86 .
  • the water pump 10 corresponds to a coolant pumping device.
  • cooling water circulation paths 81 through 86 One of the water pump 10 , the engine 20 , the water-cooled exhaust manifold 30 , the heater core 40 , the radiator 50 and the thermostat 60 is arbitrarily mounted in cooling water circulation paths 81 through 86 .
  • these components are coupled each other directly or via a pipe. A description will now be given of cooling water circulation paths 81 through 86 more specifically.
  • the first cooling water circulation path 81 is a circulation path through which the cooling water W flows in order of the water pump 10 , the engine body 21 , the heater core 40 , and the thermostat 60 that are mounted therein.
  • the cooling water W flows through the engine body 21 , it specifically flows through the water jacket 22 .
  • the second cooling water circulation path 82 is particularly a circulation path through which the cooling water W flows in order of the water pump 10 , the engine body 21 and the thermostat 60 that are mounted therein. In addition, when the cooling water W flows through the engine body 21 , it flows through the water jacket 22 and the bypass path 23 in this order particularly.
  • the third cooling water circulation path 83 is a circulation path through which the cooling water W flows in order of the water pump 10 , the water-cooled exhaust manifold 30 , the engine body 21 , and the thermostat 60 that are mounted therein.
  • the cooling water W flows through the engine body 21 , it flows through the communication path 24 and the bypass path 23 in this order particularly.
  • First through third cooling water flow paths 81 through 83 are circulation paths not including the radiator 50 .
  • the fourth cooling water circulation path 84 is particularly a circulation path through which the cooling water W flows in order of the water pump 10 , the engine body 21 , the heater core 40 , and the thermostat 60 that are mounted therein. In addition, when the cooling water W flows through the engine body 21 , the cooling water W flows through the water jacket 22 .
  • the fifth cooling water circulation path 85 is particularly a circulation path through which the cooling water W flows in order of the water pump 10 , the engine body 21 , the radiator 50 , and the thermostat 60 that are mounted therein. In addition, when the cooling water W flows through the engine body 21 , it flows through the water jacket 22 particularly.
  • the sixth cooling water circulation path 86 is particularly a circulation path through which the cooling water W in order of the water pump 10 , the water-cooled exhaust manifold 30 , the radiator 50 , and the thermostat 60 are mounted therein,
  • the flow rate changing structure 70 can arbitrarily change the flow rate of the cooling water W flowing into the water-cooled exhaust manifold 30 during the opening and closing of the thermostat 60 (i.e. during the operation of the engine 20 ).
  • the ECU 1 A is provided with a microcomputer composed of a CPU 2 , a ROM 3 , a RAM 4 and the like, and input/output circuits 5 and 6 .
  • the CPU 2 , the ROM 3 , the RAM 4 , and input/output circuits 5 and 6 are coupled each other via a bus 7 .
  • the ECU 1 A is configured to control the engine 20 mainly. More particularly, the ECU 1 A is configured to control the fuel injection valve not illustrated for example. In addition, the ECU 1 A is configured to control the actuator 75 in addition to this. These controlled objects are electrically coupled to the ECU 1 A.
  • Various sensors such as the water temperature sensor 91 , the engine rotation number sensor 91 , an air flow meter 93 (more particularly, an intake air flow rate sensor 93 a and an intake air temperature sensor 93 b ), and the throttle opening degree sensor 94 , are electrically coupled to the ECU 1 A.
  • the cooling water temperature THW is detected based on the output of the water temperature sensor 91
  • the rotation number NE is detected based on the output of the engine rotation number sensor 92
  • the intake air flow rate GA and the intake air temperature THA of the engine 20 are detected based on the output of the air flow meter 93
  • the opening degree TA of the throttle valve adjusting the intake air flow rate GA (its illustration is omitted) is detected based on the output of the throttle opening degree sensor 94 in the ECU 1 A.
  • the ROM 3 is a component to store programs where various processes executed by the CPU 2 are written and map data.
  • a control means, a determination means, a detection means, and a calculation means are functionally achieved in the ECU 1 A by the execution of the process by the CPU 2 based on programs stored in the ROM 3 with using a temporary memory region of the RAM 4 as needed.
  • a detection means detecting estimation factors including the intake air flow rate GA of the engine 20 for example, and an estimation means estimating a cooling loss Qw which is a received heat quantity that a coolant receives from the exhaust in the water-cooled exhaust manifold 30 based on estimation factors detected by the detection means (hereinafter, abbreviated as a cooling loss estimation means) are functionally achieved.
  • the reason why the above-described estimation factors include the intake air flow rate GA is because the intake air flow rate GA has a high linear correlation with the cooling loss Qw.
  • the above-described estimation factors further include at least one of the cooling water temperature THW which is a coolant temperature, the intake air temperature THA, and the rotation number NE. This is because these four factors are factors having a great effect on the cooling loss Qw.
  • the cooling loss Qw also changes.
  • the cooling water temperature THW and the intake air temperature THA can represent the operation environment condition of the engine 20 .
  • the rotation number NE can represent a magnitude of the friction of the engine 20 . Therefore, when estimating the cooling loss Qw more accurately, it is preferable that at least one of the cooling water temperature THW, the intake air temperature THA, and the rotation number NE is further included.
  • the cooling loss Qw is specifically estimated based on the formula (1).
  • a means that determines whether an operation state of the engine 20 is in a steady state or in a transient state based on the change of opening degree of the throttle valve ⁇ TA is functionally achieved as a determination means that determines an operation state of the engine 20 (hereinafter, referred to as a first operation state determination means). More specifically, the first operation state determination means determines that the operation state is in a steady state when the change of opening degree ⁇ TA is equal to or smaller than a given value, and determines that the operation state is in a transient state when the change of opening degree ⁇ TA is smaller than a given value.
  • a determination unit that determines the flow rate of the cooling water W flowing through the water-cooled exhaust manifold 30 based on the intake air flow rate GA (hereinafter, referred to as a first flow rate determination means) is functionally achieved. More specifically, the first flow rate determination means determines the flow rate of the cooling water W flowing through the water-cooled exhaust manifold 30 based on the intake air flow rate GA when the operation state of the engine 20 is in a steady state in this embodiment.
  • a determination means that determines the flow rate of the cooling water W flowing through the water-cooled exhaust manifold 30 based on the cooling loss Qw (hereinafter, referred to as a second flow rate determination means) is functionally achieved. More specifically, the second flow rate determination means determines the flow rate of the cooling water W flowing through the water-cooled exhaust manifold 30 based on the cooling loss Qw estimated by the cooling loss estimation means when the operation state of the engine 20 is in a transient state.
  • a control means that controls the flow rate of the cooling water W (hereinafter, referred to as a flow rate control means) is functionally achieved. More specifically, the flow rate control means handles the flow rate changing structure 70 (more specifically, the actuator 75 ) as a controlled object, and controls the flow rate of the cooling water W flowing through the water-cooled exhaust manifold 30 to be the flow rate determined by the first or second flow rate determination means. The flow rate of the cooling water W flowing through the water-cooled exhaust manifold 30 is determined and controlled simultaneously by determining and controlling the discharge rate of the water pump 10 .
  • the flowchart is executed repeatedly at a very short time interval during the operation of the engine 20 .
  • the ECU 1 A detects the throttle opening degree TA, and calculates the change of the throttle opening degree ⁇ TA (step S 1 ). Then, the ECU 1 A determines whether the calculated change of opening degree ⁇ TA is equal to or smaller than a given value (step S 2 ). When the determination result is Yes in the step S 2 , the operation state of the engine 20 is determined to be a steady state. At this time, the ECU 1 A detects the intake air flow rate GA (step S 3 ).
  • the ECU 1 A determines the discharge rate of the water pump 10 based on the detected intake air flow rate GA (step S 4 ). More specifically, the ECU 1 A determines the discharge rate of the water pump 10 based on the cooling water flow characteristics according to the intake air flow rate GA (hereinafter, referred to as a first flow characteristic of cooling water) at this time. Then, the ECU 1 A controls the actuator 75 , and changes the discharge rate of the water pump 10 to the determined discharge rate (step S 8 ). After the step S 8 , this flowchart is ended.
  • the operation state of the engine 20 is determined to be a transient state.
  • the ECU 1 A detects the cooling water temperature THW, the intake air temperature THA, the rotation number NE, and the intake air flow rate GA (step S 5 ). Then, the ECU 1 A calculates (estimates) the cooling loss Qw based on the formula (1) (step S 6 ). In addition, the ECU 1 A determines the discharge rate of the water pump 10 based on the calculated cooling loss Qw (step S 7 ).
  • the ECU 1 A determines the discharge rate of the water pump 10 based on the cooling water flow characteristics according to the cooling loss Qw (hereinafter, referred to as a second flow characteristic of cooling water) at this time. After the step S 7 , the process goes to the step S 8 .
  • the above-described first flow characteristic of cooling water is defined by map data stored in the ROM 3 in advance.
  • the discharge rate of the water pump 10 is set to increase and decrease in proportion to the intake air flow rate GA.
  • the flow rate of the cooling water W flowing through the water-cooled exhaust manifold 30 is set to increase and decrease in proportion to the intake air flow rate GA.
  • the above-described second flow characteristic of cooling water is defined in map data stored in the ROM 3 in advance.
  • the discharge rate of the water pump 10 is set to increase and decrease in proportion to the cooling loss Qw.
  • the flow rate of the cooling water W flowing through the water-cooled exhaust manifold 30 is set to increase and decrease in proportion to the cooling loss Qw.
  • First and second flow characteristics of cooling water are prepared with respect to each of cooling time and warming time when the flow mode of the cooling water W is switched from cooling water circulation paths 81 to 86 for example. According to this, even though the flow mode of the cooling water W is switched, a flow rate control can be executed in the flow rate changing structure 70 more properly.
  • the cooling device 100 A it is considered to increase or decrease the flow rate in proportion to the rotation number NE for example when changing the flow rate of the cooling water W to prevent or suppress the overheat of the cooling water W in the water-cooled exhaust manifold 30 .
  • the intake air flow rate GA has a very high-linear correlation with the actual cooling loss Qw (see FIG. 14 ).
  • the cooling water flow characteristic is a characteristic capable of increasing and decreasing the flow rate of the cooling water W in proportion to the intake air flow rate GA which is almost equal to the exhaust gas amount.
  • the ECU 1 A determines and changes the discharge rate of the water pump 10 (in other words, the flow rate of the cooling water W flowing through the water-cooled exhaust manifold 30 ) based on the first flow characteristic of cooling water at a steady time. That is to say, in the cooling device 100 A, regardless of the rotation number NE and the exhaust temperature, it is possible to increase the flow rate of the cooling water W flowing through the water-cooled exhaust manifold 30 properly as the calorific value becomes larger, in accordance with the calorific value of the engine 20 . Therefore, the cooling device 100 A can prevent or suppress the overheat or boiling of the cooling water W in the water-cooled exhaust manifold 30 at a steady time.
  • the ECU 1 A determines and changes the discharge rate of the water pump 10 (in other words, the flow rate of the cooling water W flowing through the water-cooled exhaust manifold 30 ) based on the second flow characteristic of cooling water at a transient time.
  • the cooling device 100 A it is possible to increase the flow rate of the cooling water W flowing through the water-cooled exhaust manifold 30 properly as the calorific value becomes larger, in accordance with the calorific value of the engine 20 in a transient state. Therefore, the cooling device 100 A can prevent or suppress the overheat or boiling of the cooling water W in the water-cooled exhaust manifold 30 also at a transient time.
  • the cooling device 100 A includes the flow rate changing structure 70 .
  • the cooling device 100 A can change the flow rate of the cooling water W flowing through the water-cooled exhaust manifold 30 even when pumping the cooling water W by the mechanical water pump 10 .
  • the flow rate of the cooling water W In order to prevent or suppress the overheat of the cooling water W in the water-cooled exhaust manifold 30 at the transient time, it is considered to set the flow rate of the cooling water W to match the maximum calorific value of the engine 20 for example. However, in this case, the flow rate of the cooling water W becomes unnecessarily large at the transient time when the calorific value is relatively small. Therefore, in this case, the water-cooled exhaust manifold 30 results in a supercooled state, and this may have a bad effect on the fuel consumption of the engine 20 and the durability and reliability of the water-cooled exhaust manifold 30 .
  • the ECU 1 A changes the flow rate of the cooling water W according to the calorific value of the engine 20 in a transient state.
  • the cooling device 100 A can prevent or suppress the fall of the water-cooled exhaust manifold 30 into the supercooled state.
  • a cooling device 100 B in accordance with the present embodiment is substantially same as the cooling device 100 A except that it includes an ECU 1 B instead of the ECU 1 A.
  • the ECU 1 B is substantially same as the ECU 1 A except that a determination means, an estimation means, and a correction means described later are further achieved functionally. Therefore, in this embodiment, the illustration of the cooling device 100 B and the ECU 1 B is omitted.
  • a means that determines whether the operation state of the engine 20 is high-rotation/high-load (hereinafter, referred to as a second operation state determination means) is functionally achieved as a determination means that determines the operation state of the engine 20 . More specifically, the second operation state determination means determines that the operation state is high-rotation/high-load when the intake air flow rate GA is equal to or greater than a given value, and determines that the operation state is not high-rotation/high-load when the intake air flow rate GA is smaller than a given value.
  • an estimation means that estimates a temperature of the wall (more specifically, exhaust pipes 301 ) of the water-cooled exhaust manifold 30 forming the path through which the exhaust gas flows (hereinafter, referred to as a wall temperature estimation means) is functionally achieved. More specifically, in the present embodiment, the wall temperature estimation means estimates that the temperature of the wall is high when the operation state of the engine 20 is high-rotation/high-load.
  • a correction means (hereinafter, referred to as a flow rate correction means) that corrects the discharge rate of the water pump 10 determined by one of first and second flow rate determination means in accordance with the operation state of the engine 20 in the ECU 1 B based on the estimation by the wall temperature estimation means, is functionally achieved.
  • a flow rate correction means that corrects the discharge rate of the water pump 10 determined by one of first and second flow rate determination means in accordance with the operation state of the engine 20 in the ECU 1 B based on the estimation by the wall temperature estimation means.
  • the flow rate correction means is achieved as described hereinafter particularly. That is to say, the flow rate correction means calculates the accumulated amount of intake air flow rate ⁇ GA by accumulating the intake air flow rate GA when the temperature of the wall is high. Then, the flow rate correction means adds the flow rate correction amount based on the calculated accumulated amount of intake air flow rate ⁇ GA to the discharge rate of the water pump 10 which is set in one of first and second flow characteristics of cooling water in accordance with the operation state of the engine 20 .
  • the flow rate correction means updates the accumulated amount of intake air flow rate ⁇ GA by subtracting the current intake air flow rate GA from the accumulated amount of intake air flow rate ⁇ GA. Then, when the updated accumulated amount of intake air flow rate ⁇ GA is equal to or greater than a given value (e.g. 0), the flow rate correction means adds the flow rate correction amount according to the accumulated amount of intake air flow rate ⁇ GA to the flow rate of the cooling water W which is set in one of first and second flow characteristics of cooling water in accordance with the operation state of the engine 20 .
  • a given value e.g. 0
  • the flow rate correction amount is set to increase or decrease in proportion to the accumulated amount of intake air flow rate ⁇ GA in a high-load region in map data stored in the ROM 3 in advance as illustrated in FIG. 15 .
  • the ECU 1 B detects the intake air flow rate GA (step S 11 ). Then, the ECU 1 B determines whether the detected intake air flow rate GA is equal to or greater than a given value which is a determination threshold value for the high-load determination (step S 12 ). When the determination result is Yes in the step S 12 , the operation state of the engine 20 is determined to be high-rotation/high-load. When the determination result is Yes in the step S 12 , it is estimated that the temperature of the wall is high. At this time, the ECU 1 B turns the high-load determination flag to ON (step S 13 ). In FIG. 17 , the state at the time T 1 corresponds to this state.
  • the ECU 1 B accumulates the detected intake air flow rate GA, and calculates the accumulated amount of intake air flow rate ⁇ GA (step 14 ). Furthermore, the ECU 1 B adds the flow rate correction amount according to the accumulated amount of intake air flow rate ⁇ GA to the discharge rate of the water pump 10 set in one of first and second flow characteristics of cooling water in accordance with the operation state of the engine 20 (step S 15 ). After the step S 15 , this flowchart is ended. Then, the ECU 1 B executes procedures from steps S 11 through S 15 repeatedly till the determination result becomes No in the step S 12 .
  • the operation state of the engine 20 is determined not to be high-rotation/high-load.
  • the determination result is No in the step S 12
  • the ECU 1 B turns the high-load determination flag to OFF (step S 16 ).
  • the state at the time T 2 corresponds to above-described state.
  • the ECU 1 B subtracts the current intake air flow rate GA from the accumulated amount of intake air flow rate ⁇ GA, and updates the accumulated amount of intake air flow rate ⁇ GA (step S 17 ).
  • the ECU 1 B determines whether the calculated accumulated amount of intake air flow rate ⁇ GA is equal to or greater than a given value (here, 0) (step S 18 ).
  • step S 18 When the determination result is Yes in the step S 18 , the process goes to the step S 15 . Then, the ECU 1 B executes above-described procedures repeatedly till the determination result becomes No in the step S 18 . On the other hand, when the determination result is Yes in the step S 18 , the ECU 1 B resets the accumulated amount of intake air flow rate ⁇ GA (step S 19 ). In FIG. 17 , a state at the time T 3 corresponds to this state. According to a sequence of above operations, the amount corresponding to the area of the accumulated amount of intake air flow rate ⁇ GA illustrated is added to the flow rate correction amount.
  • the temperature of the wall of the water-cooled exhaust manifold 30 remains high for a certain period as illustrated in FIG. 18 with a dashed line.
  • the cooling capacity of the water-cooled exhaust manifold 30 decreases because the flow rate of the cooling water W decreases as the rotation number NE decreases. Therefore, in this case, the flow rate determined based on the intake air flow rate GA and the cooling loss Qw is not enough for cooling, and there is a possibility of the overheat or boiling of the cooling water W in the water-cooled exhaust manifold 30 . More specifically, as illustrated in FIG. 19 , the temperature of the cooling water W becomes high, and there is a possibility that the state where the boiling is locally recognized is achieved.
  • the ECU 1 B adds the flow rate correction amount based on the accumulated amount of intake air flow rate ⁇ GA to the discharge rate of the water pump 10 which is set in one of first and second flow characteristics of cooling water in accordance with the operation state of the engine 20 . According to this, the flow rate of the cooling water W flowing through the water-cooled exhaust manifold 30 is further increased. Therefore, it is possible to cool the wall of the water-cooled exhaust manifold 30 which remains to have a high temperature for a certain period properly.
  • the cooling device 100 B can prevent or suppress the overheat or boiling of the cooling water W in the water-cooled exhaust manifold 30 even when the operation state of the engine 20 further moves from an operating state of high-rotation/high-load to an operation state of low-rotation/high-load.
  • the flow rate changing structure 70 is provided as the flow rate change means.
  • the present invention is not limited to this case, and the flow rate change means may be other structures capable of changing the flow rate of the coolant.
  • the flow rate change means can be achieved by the variable water pump pulley 76 illustrated in FIG. 20 .
  • This pulley 76 can be applied instead of the pulley 72 .
  • the idler pulley 74 is utilized to adjust the tension of the belt 73 , and the actuator 75 becomes unnecessary.
  • the pulley 76 includes a pair of pulley members 76 a with a circular truncated cone shape.
  • the pulley 76 includes a structure which can drive pulley members 76 a to move away from or come close to each other around the center in the axis direction.
  • the belt 73 is looped around the pulley 76 so that it is looped around each pulley member 76 a equally.
  • the pulley 76 is hydraulically-actuated, is applied as the controlled object instead of the actuator 75 , and is able to drive each pulley member 76 a by switching the hydraulic pressure under the control of the ECU 1 A.
  • each pulley member 76 a is a position where the pulley members 76 a contact with each other as illustrated in FIG. 20( a ).
  • the diameter of the belt 73 is reduced on the pulley 76 . Therefore, according to this, the rotation of the water pump 10 is increased, and the discharge rate can be increased.
  • the discharge rate of the water pump 10 can be decreased by operating the pulley 76 inversely.
  • the flow rate determination means may be one of the first flow rate determination means and the second flow rate determination means at both the steady time and the transient time.
  • the control can be simplified.
  • the steady time and the transient time are repeated in a relatively short period, it is possible to prevent the flow rate from being changed at different levels repeatedly by the first flow rate determination means and the second flow rate determination means, and to increase the reliability of the flow rate change means and to achieve the stabilization of the control.
  • the first flow rate determination means may determine a flow rate at least at a steady time
  • the second flow rate determination means may determine the flow rate at least at a transient time
  • first and second flow rate determination means determines the flow rate at a steady time and a transient time
  • the second flow rate determination means which determines a flow rate based on the received heat quantity of the exhaust system cooling means, is preferable because the control of flow rate is carried out more properly as a whole.
  • the correction means may correct the flow rate determined by the flow rate determination means.
  • first and second flow rate determination means may determine the flow rate when the correction means corrects the flow rate. In this case, it is possible to improve the reliability of the flow rate change means and stabilize the control.
  • the coolant pumping device is the mechanical water pump 10
  • the present invention is not limited to this case, and it is possible to prevent or suppress the overheat or boiling of the coolant in the exhaust cooling means by applying the present invention even in a case where the coolant pumping device is an electric water pump.
  • the exhaust system cooling means is the water-cooled exhaust manifold 30 .
  • the present invention is not limited to this case, and the exhaust system cooling means may be other arbitrary structures capable of cooling the engine exhaust system by a flowing coolant.
  • the exhaust system cooling means may be achieved by an adapter that is located between the exhaust manifold and the engine for example and connects them.
  • each means such as the flow rate determination means, the estimation means, and the correction means may be achieved by one or combination of other electronic control devices and hardware such as a dedicated circuit.
  • Each means such as the flow rate determination means, the estimation means and the correction means may be achieved by electronic control devices, hardware such as electronic circuits, or the combination of an electronic control devices and hardware such as an electronic circuit for example in a distributed manner.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Exhaust Gas After Treatment (AREA)
  • Combined Controls Of Internal Combustion Engines (AREA)
US13/201,717 2009-05-08 2009-05-08 Engine cooling device Abandoned US20120047893A1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2009/058657 WO2010128549A1 (ja) 2009-05-08 2009-05-08 エンジンの冷却装置

Publications (1)

Publication Number Publication Date
US20120047893A1 true US20120047893A1 (en) 2012-03-01

Family

ID=43050062

Family Applications (1)

Application Number Title Priority Date Filing Date
US13/201,717 Abandoned US20120047893A1 (en) 2009-05-08 2009-05-08 Engine cooling device

Country Status (4)

Country Link
US (1) US20120047893A1 (ja)
JP (1) JP5196014B2 (ja)
CN (1) CN102414413A (ja)
WO (1) WO2010128549A1 (ja)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013132179A1 (fr) * 2012-03-06 2013-09-12 Renault S.A.S. Dispositif de refroidissement rapide pour véhicule automobile comprenant une pièce munie d'un diffuseur
FR3002281A1 (fr) * 2013-02-19 2014-08-22 Peugeot Citroen Automobiles Sa Circuit de refroidissement pilote pour moteur thermique de vehicule automobile et moteur thermique de vehicule automobile correspondant

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013007338A (ja) * 2011-06-24 2013-01-10 Toyota Motor Corp 内燃機関冷却水循環装置

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030150406A1 (en) * 2002-02-13 2003-08-14 Isao Takagi Cooling system for internal combustion engine
US6620007B2 (en) * 2001-02-28 2003-09-16 Yamaha Marine Kabushiki Kaisha Cooling water jacket for small watercraft engine
US6880498B2 (en) * 2000-06-22 2005-04-19 Toyota Jidosha Kabushiki Kaisha Internal combustion engine including heat accumulation system, and heat carrier supply control system
US7013646B1 (en) * 2004-11-18 2006-03-21 The Gates Corporation Auxiliary power system for a motor vehicle
US20060086546A1 (en) * 2002-02-08 2006-04-27 Green Vision Technology, Llc Internal combustion engines for hybrid power train
US20060107920A1 (en) * 2004-11-18 2006-05-25 Alexander Serkh Auxiliary power system for a motor vehicle
US20060207241A1 (en) * 2005-03-18 2006-09-21 Toyota Jidosha Kabushiki Kaisha Control apparatus for internal combustion engine
US20080127933A1 (en) * 2006-12-01 2008-06-05 Paul Blumberg Multiple Combustion Mode Engine Using Direct Alcohol Injection
US20080223317A1 (en) * 2007-03-16 2008-09-18 Toyota Jidosha Kabushiki Kaisha Cooling apparatus for internal combustion engine
US20080264036A1 (en) * 2007-04-24 2008-10-30 Bellovary Nicholas J Advanced engine control
US8276552B2 (en) * 2004-06-10 2012-10-02 Achates Power, Inc. Opposed piston engine

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03179122A (ja) * 1989-12-07 1991-08-05 Fuji Heavy Ind Ltd 触媒コンバータの温度制御装置
JP2006112233A (ja) * 2004-10-12 2006-04-27 Aisan Ind Co Ltd エンジンの冷却装置
JP2006342680A (ja) * 2005-06-07 2006-12-21 Toyota Motor Corp 内燃機関の冷却装置
JP2008255871A (ja) * 2007-04-04 2008-10-23 Toyota Motor Corp 冷却装置

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6880498B2 (en) * 2000-06-22 2005-04-19 Toyota Jidosha Kabushiki Kaisha Internal combustion engine including heat accumulation system, and heat carrier supply control system
US6620007B2 (en) * 2001-02-28 2003-09-16 Yamaha Marine Kabushiki Kaisha Cooling water jacket for small watercraft engine
US20060086546A1 (en) * 2002-02-08 2006-04-27 Green Vision Technology, Llc Internal combustion engines for hybrid power train
US20030150406A1 (en) * 2002-02-13 2003-08-14 Isao Takagi Cooling system for internal combustion engine
US8276552B2 (en) * 2004-06-10 2012-10-02 Achates Power, Inc. Opposed piston engine
US7013646B1 (en) * 2004-11-18 2006-03-21 The Gates Corporation Auxiliary power system for a motor vehicle
US20060107920A1 (en) * 2004-11-18 2006-05-25 Alexander Serkh Auxiliary power system for a motor vehicle
US20060207241A1 (en) * 2005-03-18 2006-09-21 Toyota Jidosha Kabushiki Kaisha Control apparatus for internal combustion engine
US20080127933A1 (en) * 2006-12-01 2008-06-05 Paul Blumberg Multiple Combustion Mode Engine Using Direct Alcohol Injection
US20080223317A1 (en) * 2007-03-16 2008-09-18 Toyota Jidosha Kabushiki Kaisha Cooling apparatus for internal combustion engine
US20080264036A1 (en) * 2007-04-24 2008-10-30 Bellovary Nicholas J Advanced engine control

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013132179A1 (fr) * 2012-03-06 2013-09-12 Renault S.A.S. Dispositif de refroidissement rapide pour véhicule automobile comprenant une pièce munie d'un diffuseur
FR2987871A1 (fr) * 2012-03-06 2013-09-13 Renault Sa Dispositif de refroidissement rapide pour vehicule automobile comprenant une piece munie d'un diffuseur
US9482141B2 (en) 2012-03-06 2016-11-01 Renault S.A.S. Rapid cooling device for a motor vehicle comprising a component fitted with a diffuser
FR3002281A1 (fr) * 2013-02-19 2014-08-22 Peugeot Citroen Automobiles Sa Circuit de refroidissement pilote pour moteur thermique de vehicule automobile et moteur thermique de vehicule automobile correspondant

Also Published As

Publication number Publication date
CN102414413A (zh) 2012-04-11
JP5196014B2 (ja) 2013-05-15
WO2010128549A1 (ja) 2010-11-11
JPWO2010128549A1 (ja) 2012-11-01

Similar Documents

Publication Publication Date Title
EP2469053B1 (en) Control device for variable water pump
EP2444638B1 (en) Control device for vehicle
US10519875B2 (en) Diagnostic device
US9611811B2 (en) Control device for cooling system
WO2010143265A1 (ja) 内燃機関の制御装置
US20120216761A1 (en) Cooling device for engine
JP2008232031A (ja) 排気熱回収装置
JP4581837B2 (ja) 内燃機関の冷却装置
JP2012149575A (ja) 内燃機関の冷却装置
US20120047893A1 (en) Engine cooling device
US8978599B2 (en) Cooling apparatus of internal combustion engine for vehicle
CN111878209B (zh) 一种高效混动发动机冷却系统及发动机冷却方法
JP5267654B2 (ja) エンジンの冷却装置
US20160305309A1 (en) Cooling apparatus for internal combustion engine
JP2010242525A (ja) ウォータポンプの制御装置
WO2011148464A1 (ja) 内燃機関の冷却装置
US8560170B2 (en) Method for estimating amount of heat received by refrigerant and controller
JP2011220156A (ja) 冷却システムの制御装置
US8434452B2 (en) Control device for internal combustion engine
JP2008255871A (ja) 冷却装置
JP2019178609A (ja) Ｐｃｖシステム
JP2006161744A (ja) 車両の制御装置

Legal Events

Date Code Title Description
AS Assignment

Owner name: TOYOTA JIDOSHA KABUSHIKI KAISHA, JAPAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:HOSHI, KOICHI;SHINODA, YOSHIHISA;REEL/FRAME:026761/0808

Effective date: 20110807

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION