JP2010096152A - Catalyst warm-up control system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a catalyst warm-up control system capable of effectively performing the early warm-up of a catalyst. <P>SOLUTION: In such a state that an engine 2 is stopped, that is, when a vehicle door is unlocked before start of the engine 2, the warmed cooling water stored in a heat storage tank 22 is supplied to the exhaust components including an exhaust manifold 3, turbine housing 5, exhaust pipe 7 and heat exchanger 9. Besides, when the heat storage tank 22 is in an empty state, the exhaust gas is accumulated in the tank 22 by supplying the warmed cooling water to the exhaust components during operation of the engine 2, and air assist is performed by blowing down the exhaust gas accumulated in the tank 22 to a turbine wheel 6. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a catalyst warm-up control system, and more particularly to a catalyst warm-up control system having a heat storage tank for storing heated cooling water.

  Conventionally, after the internal combustion engine is started, catalyst warm-up control is performed to raise the temperature of the exhaust gas purifying catalyst to the activation temperature. As the catalyst warm-up control, for example, by increasing or decreasing the fuel injection amount, oxygen can be supplied by lean combustion and combustible components (CO (carbon monoxide), etc.) by rich combustion can be supplied. What is warmed up is known, and by executing such control, the oxidation reaction of CO in the catalyst is increased, and the catalyst is heated by the heat generated by this oxidation reaction, thereby promoting the warming up of the catalyst. (See, for example, Patent Document 1).

As another catalyst warm-up control, when the catalyst is not warmed up, the catalyst is warmed up by opening a valve (waist gate valve) provided on the passage that bypasses the turbocharger. Is known (see, for example, Patent Document 2).
JP-A-9-88663 JP 2001-107790 A JP 2005-351173 A

  However, in such conventional catalyst warm-up control, the temperature of the exhaust system parts is low immediately after the start of the internal combustion engine, so that oxygen supply by lean combustion and supply of combustible components by rich combustion are performed, or Even when the wastegate valve provided on the passage that bypasses the supercharger is opened, the exhaust gas is not easily heated due to heat exchange with low-temperature exhaust system components. For this reason, the heat of the catalyst is taken away by the low-temperature exhaust gas, and it may take a long time until the catalyst is activated.

On the other hand, a heat storage system is known in which when the internal combustion engine is cold, cooling water stored in a heat storage tank while being kept warm is supplied to a cooling water passage in the internal combustion engine by an electric water pump (see, for example, Patent Document 3). ).
However, this heat storage system supplies the cooling water stored in the heat storage tank to the internal combustion engine to achieve early warm-up of the internal combustion engine, and cannot warm up the catalyst early. The controlled object is completely different.

  The present invention has been made to solve the above-described conventional problems, and an object thereof is to provide a catalyst warm-up control system capable of effectively warming up the catalyst early.

  In order to achieve the above object, a catalyst warm-up control system according to the present invention is provided in (1) an exhaust gas exhaust path between an internal combustion engine and a catalyst that purifies exhaust gas discharged from the internal combustion engine. A catalyst warm-up control system for warming up the catalyst by heating the exhaust system parts, a heat storage tank for storing the heated coolant, and a cooling water circulation for circulating the coolant to the exhaust system parts Means, cooling water supply means for supplying cooling water stored in the heat storage tank to the cooling water circulation means, operating state detecting means for detecting the operating state of the internal combustion engine, and predetermined riding conditions are established A boarding condition judging means for judging whether or not the internal combustion engine is stopped based on the driving condition detecting means, and the boarding condition judging means establishes a boarding condition. Doo. If it is determined, and a one and a cooling water control means for supplying cooling water stored in the heat storage tank to the cooling water circulating means by actuating the cooling water supply means.

  With this configuration, when a predetermined riding condition such as a state in which the internal combustion engine is stopped, that is, a vehicle door is unlocked before the internal combustion engine is started, warm cooling water stored in the heat storage tank is established. Is supplied to the cooling water circulating means, so that the warm cooling water can be supplied to the exhaust system parts, and the exhaust system parts in the cold state before starting the internal combustion engine can be heated.

  For this reason, after the internal combustion engine is started, the heat of the exhaust gas discharged from the internal combustion engine is not easily taken away by the exhaust system parts, and the catalyst can be raised to the activation temperature early, which effectively warms up the catalyst. Can be done automatically.

  (1) In the catalyst early warm-up control system according to (1), (2) the exhaust system component communicates with at least the exhaust port of the internal combustion engine, and the exhaust manifold constituting the exhaust system component, and the downstream of the exhaust manifold An exhaust gas circulation system that includes a turbocharger that includes a turbine housing that is provided on a side and houses a turbine wheel that is rotated by exhaust gas, and that circulates the exhaust gas between the exhaust manifold and the heat storage tank. An exhaust gas circulation member having a passage; first opening / closing means for opening / closing the exhaust gas circulation passage; second opening / closing means for opening / closing an exhaust passage downstream of the turbine wheel; An opening / closing control means for performing opening / closing control of the first opening / closing means and the second opening / closing means based on detection information; And a one having.

  With this configuration, the warm cooling water in the heat storage tank is supplied to the exhaust system components during operation of the internal combustion engine, so that the exhaust gas can be stored in the heat storage tank when the heat storage tank is empty. .

For example, when the vehicle is decelerating, the first opening / closing means is opened and the second opening / closing means is closed, and the heat storage tank communicates with the exhaust manifold through the exhaust gas circulation passage, whereby the exhaust gas is accumulated in the heat storage tank. To be.
Further, when the vehicle is accelerated, the first opening / closing means and the second opening / closing means are opened, and the exhaust gas accumulated in the heat storage tank is supplied to the turbine wheel of the supercharger through the exhaust gas circulation passage. Use air assist for the turbine wheel.
In this way, a single heat storage tank can be used in combination as a tank for storing heated cooling water and a tank for storing exhaust gas pressure, reducing the mounting space of the heat storage tank and improving the supercharging characteristics. Can be improved.

  In the catalyst warm-up control system described in (2) above, (3) heat exchange means for exchanging heat of cooling water flowing through the cooling water member is provided, and the cooling water control means includes the operation state detection means. Based on the detected information, the cooling water circulating through the cooling water circulating means is circulated through the heat exchange means.

  With this configuration, the cooling water is circulated through the heat exchange means during the operation of the internal combustion engine, so that the exhaust system parts can be cooled by the low-temperature cooling water, and the exhaust system parts are heated to a high temperature by the high-temperature exhaust gas. Can be prevented. For this reason, it is not necessary to configure the exhaust system parts from expensive heat-resistant materials, and it is possible to prevent an increase in the manufacturing cost of the exhaust system parts.

  Further, during the operation of the internal combustion engine, the cooling water is circulated through the heat exchanging means, so that the heat storage tank can be emptied, and the exhaust gas is stored in the heat storage tank so that the air assist pressure storage tank is stored. Can be used reliably.

  ADVANTAGE OF THE INVENTION According to this invention, the catalyst warm-up control system which can perform early warm-up of a catalyst effectively can be provided.

Hereinafter, an embodiment of a catalyst warm-up control system according to the present invention will be described with reference to the drawings.
1 to 7 are diagrams showing an embodiment of a catalyst warm-up control system according to the present invention.
First, the configuration will be described.
FIG. 1 is a diagram showing a vehicle 1 equipped with a catalyst warm-up control system. The vehicle 1 includes a four-cycle diesel engine (hereinafter simply referred to as an engine) 2 as an internal combustion engine. Although the engine 2 is an in-line four-cylinder type, the number of cylinders and the cylinder arrangement of the engine are not limited thereto.
Each cylinder of the engine 2 is provided with an injector (not shown) that directly injects fuel into the cylinder, and the injector of each cylinder is connected to a common common rail (not shown). In the common rail, high-pressure fuel pressurized by a supply pump (not shown) is stored, and fuel is supplied from the common rail to each injector.

  The engine 2 is provided with a cylinder block and a piston (not shown), a crankshaft, and a cylinder head. A cylinder bore (not shown) is formed in the cylinder block, and the piston reciprocates in the cylinder bore. The piston is in sliding contact with the inner wall surface of the cylinder bore, and a cylinder head is coupled to the cylinder block so as to face the piston and close the cylinder bore.

  The cylinder head is provided with an intake port and an exhaust port (not shown) corresponding to each cylinder, and an intake valve and an exhaust valve (not shown) are provided corresponding to the intake port and the exhaust port. The intake valve and the exhaust valve are configured to be openable and closable at a predetermined timing according to the rotation angle position of the crankshaft.

  An exhaust manifold 3 is attached to the cylinder head. The exhaust manifold 3 includes a collecting pipe 3a and a plurality of branch pipes 3b branched from the collecting pipe 3a and connected to the exhaust port of the cylinder head. ing.

  A turbine housing 5 of the supercharger 4 is connected downstream of the exhaust manifold 3 in the exhaust gas discharge direction (hereinafter simply referred to as downstream), and a turbine wheel 6 is provided in the turbine housing 5. Further, an exhaust pipe 7 is connected downstream of the turbine housing 5, and a catalyst 8 for purifying exhaust gas exhausted from the engine 2 is connected downstream of the exhaust pipe 7.

  Examples of the catalyst 8 include an oxidation catalyst, an occlusion reduction type or selective reduction type NOx catalyst, one of DPF (Diesel Particulate Filter), DPNR (Diesel Particulate-NOx-Reduction system), or a combination thereof. Can be used. Further, a silencer or the like (not shown) is provided downstream of the catalyst 8.

  In addition, a heat exchanger 9 that functions as a heater core of the air conditioner is provided on the outer peripheral portion of the exhaust pipe 7. The heat exchanger 9 is disposed between the exhaust gas flowing through the exhaust pipe 7 and the cooling water. Heat exchange is performed, and the air blown to the heat exchanger 9 can be heated and taken into the room. The heat exchanger 9 also has a function of heating the exhaust pipe 7 when the catalyst is warmed up. This function will be described later.

  That is, in the present embodiment, the exhaust manifold 3, the supercharger 4, the exhaust pipe 7, and the heat exchanger 9 are provided between the engine 2 and the catalyst 8. In the present embodiment, the exhaust manifold 3, The feeder 4, the exhaust pipe 7 and the heat exchanger 9 constitute exhaust system parts.

  An intake manifold 10 is attached to the cylinder head of the engine 2. The intake manifold 10 includes a collecting pipe 10a and a plurality of branch pipes 10b branched from the collecting pipe 10a and connected to the intake port of the cylinder head. And.

  The intake manifold 10 is connected to a compressor housing 12 of the supercharger 4 via an intake pipe 11, and the compressor housing 12 is connected to an intake pipe 13 provided with an air cleaner 14.

  A compressor wheel 15 is accommodated in the compressor housing 12, and the compressor wheel 15 is connected to the turbine wheel 6 via a wheel shaft 16. Further, the turbine housing 5 and the compressor housing 12 are connected by a bearing housing 17, and the bearing housing 17 rotatably supports the wheel shaft 16.

  In the present embodiment, the air sucked through the air cleaner 14 is compressed by the compressor wheel 15 of the supercharger 4, supplied to the intake manifold 10 through the intake pipe 11, and distributed by the intake manifold 10. Thus, it flows into each cylinder of the engine 2.

  Further, exhaust gas exhausted from the engine 2 to the exhaust manifold 3 is blown to the turbine wheel 6 of the supercharger 4, whereby the compressor wheel 15 is rotated via the wheel shaft 16, and the intake pipe 11 passes through the air cleaner 14. The air sucked in is compressed by the compressor wheel 15 of the supercharger 4 as described above.

  On the other hand, a catalyst warm-up control system 21 is mounted on the vehicle 1 of the present embodiment. The catalyst warm-up control system 21 includes a heat storage tank 22, a water pump 23, a radiator 24, a heat storage tank 22, and a radiator 24. And the exhaust manifold 3, the supercharger 4, the exhaust pipe 7 and the heat exchanger 9, pipes 25 to 32 for circulating cooling water, electromagnetic three-way solenoid valves 33 and 34, an air assist mechanism 35, An ECU (Electronic Control Unit) 100 that controls the three-way electromagnetic valves 33 and 34 and the air assist mechanism 35 is configured.

The heat storage tank 22 is provided with a heat insulating material or the like inside, and has a structure capable of keeping the high-temperature heated cooling water stored in the heat storage tank 22 over a long period of time.
The other end of the pipe 25 is connected to the heat storage tank 22, and one end of the pipe 25 is connected to the three-way solenoid valve 33, and the pipe 26 and one end of the pipe 31 are connected to the three-way solenoid valve 33. Has been.

  The three-way solenoid valve 33 includes a first port 33a to which one end of the pipe 25 is connected, a second port 33b to which one end of the pipe 26 is connected, and a third port 33c to which one end of the pipe 31 is connected. And a valve body for switching between a first communication position for communicating the first port 33a and the second port 33b and a second communication position for communicating the second port 33b and the third port 33c. The first communication position and the second communication position are switched by energizing the coil in accordance with a command from the ECU 100 to drive the valve body.

  The other end of the pipe 31 is connected to a radiator 24 as heat exchange means, and the other end of the pipe 26 is connected to the exhaust manifold 3. The pipe 26 is provided with an electric water pump 23 using a battery (not shown) as a drive source. The water pump 23 is driven to rotate forward and backward in response to a command from the ECU 100.

  Further, the other end of the bypass pipe 32 is connected in the middle of the pipe 26, and one end of the bypass pipe 32 is connected to the three-way solenoid valve 34. In addition, one end portions of the pipe 30 and the pipe 29 are connected to the three-way solenoid valve 34.

  The three-way solenoid valve 34 includes a first port 34 a to which one end of the pipe 30 is connected, a second port 34 b to which one end of the pipe 29 is connected, and a third port 34 c to which one end of the bypass pipe 32 is connected. And a valve body for switching between a first communication position for communicating the first port 34a and the second port 34b and a second communication position for communicating the second port 34b and the third port 34c. The first communication position and the second communication position are switched by energizing the coil in accordance with a command from the ECU 100 to drive the valve body.

The other end of the pipe 30 is connected to the radiator 24, and the other end of the pipe 29 is connected to the heat exchanger 9. One end of the pipe 27 is connected to the exhaust manifold 3, and the other end of the pipe 27 is connected to the turbine housing 5 of the supercharger 4.
One end of the pipe 28 is connected to the turbine housing 5 of the supercharger 4, and the other end of the pipe 28 is connected to the heat exchanger 9.

  In the present embodiment, when supplying the cooling water stored in the heat storage tank 22 in the heat retaining state to the exhaust system parts, the valve body of the three-way solenoid valve 33 is switched to the first communication position, thereby As a result, the first port 33a and the second port 33b are communicated with each other, and the communication between the second port 33b and the third port 33c is cut off, so that the piping 25 and the piping 26 are communicated.

  Further, by switching the valve body of the three-way solenoid valve 34 to the second communication position, the communication between the first port 34a and the second port 34b is blocked and the second port 34b and the third port 34c are communicated. Thus, the pipe 29 and the bypass pipe 32 are communicated.

  By driving the water pump 23 in this state, the cooling water flows through the piping 26 in the order of the exhaust manifold 3, the piping 27, the turbine housing 5, the piping 28, and the heat exchanger 9, and this cooling water passes through the radiator 24. Without being passed, the exhaust gas is supplied to the exhaust manifold 3 through the pipe 29, the bypass pipe 32 and the pipe 26. That is, warm exhaust water circulates through the pipe 26, the exhaust manifold 3, the pipe 27, the turbine housing 5, the pipe 28, the heat exchanger 9, the pipe 29, the bypass pipe 32, and the pipe 26, thereby heating the exhaust system components. .

  Further, when the heat storage tank 22 becomes empty, the valve body of the three-way solenoid valve 33 is switched to the second communication position, whereby the second port 33b and the third port 33c are communicated by the valve body, and the first port 33a The piping 29 and the bypass piping 32 are communicated with each other by blocking communication with the second port 33b.

  For this reason, the cooling water does not return to the heat storage tank 22, but the warm cooling water is connected to the pipe 26, the exhaust manifold 3, the pipe 27, the turbine housing 5, the pipe 28, the heat exchanger 9, the pipe 29, the bypass pipe 32 and the pipe 26. Circulate.

  When the cooling water of the engine 2 reaches a predetermined temperature (for example, 80 ° C.) or higher, the valve body of the three-way solenoid valve 34 is switched to the first communication position to connect the first port 34a and the second port 34b. The communication between the second port 34b and the third port 34c is cut off, so that the radiator 24 and the pipe 29 are connected via the pipe 30.

  For this reason, the cooling water discharged from the pipe 29 after cooling the exhaust system parts is supplied to the radiator 24 via the pipe 29 and the pipe 30, cooled by the radiator 24 and discharged from the pipe 31, and then the exhaust system parts again. To be supplied.

That is, the cooling water cooled by the radiator 24 circulates through the pipe 31, the pipe 26, the exhaust manifold 3, the pipe 27, the turbine housing 5, the pipe 28, the heat exchanger 9, the pipe 29, the pipe 30, and the radiator 24.
In the present embodiment, the pipe 25, the three-way solenoid valve 33, and the water pump 23 constitute the cooling water supply means, and the pipe 26, the pipe 27, the pipe 28, the pipe 29, the pipe 30, the pipe 31, the bypass pipe 32, and the three-way solenoid. The valves 33 and 34 and the water pump 23 constitute cooling water circulation means.

2-4 is a figure which shows the distribution structure of the cooling water of the exhaust manifold 3, the turbine housing 5, and the heat exchanger 9, respectively.
First, the flow structure of the cooling water in the exhaust manifold 3 will be described with reference to FIG. FIG. 2 is a view showing a cross section of the collecting pipe 3a of the exhaust manifold 3, and cooling water passages 41 and 42 are formed in the upper and lower portions of the collecting pipe 3a, respectively. Cooling water inflow portions 41a and 42a are formed at one end of the cooling water passages 41 and 42, and the inflow portions 41a and 42a are connected to the other end of the pipe 26 as shown in FIG. ing. Note that the other end of the pipe 26 has a bifurcated shape and can be connected to a pair of inflow portions 41a and 42a.

  Cooling water outflow portions 41b and 42b are formed at the other end portions of the cooling water passages 41 and 42, and the outflow portions 41b and 42b are connected to one end portion of the pipe 27 as shown in FIG. Has been. The other end of the pipe 27 has a bifurcated shape and can be connected to a pair of outflow portions 41b and 42b.

  In such an exhaust manifold 3, warm cooling water in the heat storage tank 22 flows from the pipe 26 into the cooling water passages 41 and 42 through the inflow portions 41 a and 42 a, and then passes through the cooling water passages 41 and 42. Then, the exhaust manifold 3 is warmed by being discharged from the outflow portions 41b and 42b.

  Further, when cooling the exhaust manifold 3 exposed to the high-temperature exhaust gas, the cooling water cooled by the radiator 24 flows into the cooling water passages 41 and 42 from the pipe 26 through the inflow portions 41a and 42a. Thus, the exhaust manifold 3 is cooled.

FIG. 3 is a view showing a cooling water flow structure of the turbine housing 5, and shows a cross-sectional view of the supercharger 4.
In FIG. 3, the turbine wheel 6, the compressor wheel 15, and the wheel shaft 16 are disposed on the same axis and are integrally assembled. As the turbine wheel 6 rotates, the wheel shaft 16 and the compressor wheel 15 are moved together. It rotates around the axis.

  The turbine wheel 6 includes a large number of turbine blades 6a on the outer peripheral surface, and the turbine wheel 6 is made of steel (carbon steel) having heat resistance because it is exposed to high-temperature (for example, 600 to 800 ° C.) exhaust gas. Yes.

  Further, the turbine housing 5 is formed with a scroll chamber 43 having a spiral shape so as to surround the turbine wheel 6, and the scroll chamber 43 includes an exhaust gas intake port (not shown) that opens in a tangential direction of the wheel shaft 16, and An exhaust gas discharge port 44 opened in the axial direction of the wheel shaft 16 is provided. The exhaust gas intake port is connected to the exhaust manifold 3, and the exhaust gas discharge port 44 is connected to the exhaust pipe 7.

  On the other hand, the compressor wheel 15 includes a large number of compressor blades 15a on the outer peripheral surface, and the compressor wheel 15 is formed of a lightweight aluminum alloy or synthetic resin in order to suppress the turbo lag.

  A spiral diffuser 45 is formed in the compressor housing 12 so as to surround the compressor wheel 15. The diffuser 45 includes an intake air intake 46 that opens in the axial direction of the wheel shaft 16 and a supercharged air discharge port (not shown) that opens in the tangential direction of the wheel shaft 16. The intake air intake 46 is connected to the intake pipe 13, and the supercharged air discharge outlet is connected to the intake pipe 11.

  The wheel shaft 16 is inserted through a bearing member 47 formed in the bearing housing 17. The bearing member 47 has a cylindrical space formed therein, and a bearing metal 48 is loosely fitted on the inner peripheral surface thereof. Further, the inner peripheral surface of the bearing metal 48 is loosely fitted to the wheel shaft 16, and the wheel shaft 16 is rotatably supported by the bearing metal 48.

  Further, a cooling water passage 49 is formed in the turbine housing 5, and the cooling water passage 49 is formed at a position close to the scroll chamber 43 and on the exhaust gas discharge port 44 side over substantially the entire periphery thereof. Has been.

  The cooling water passage 49 has an upstream end connected to the pipe 27 and a downstream end connected to the pipe 28. For this reason, when the warm cold air in the heat storage tank 22 is introduced into the cooling water passage 49 through the pipe 27 as the water pump 23 is driven, the turbine housing 5 and the turbine wheel 6 are heated and cooled from the radiator 24 through the pipe 27. When low-temperature cooling water is supplied to the water passage 49, the turbine housing 5 and the turbine wheel 6 are cooled.

FIG. 4 is a diagram showing a cooling water flow structure of the heat exchanger 9, and is a cross-sectional view of the heat exchanger 9.
In FIG. 4, a water jacket 51 formed in a cylindrical shape is provided on the outer peripheral portion of the exhaust pipe 7, and the water jacket 51 is disposed coaxially with the exhaust pipe 7 and separates the outer periphery of the exhaust pipe 7. And besiege.

  Both end portions in the axial direction of the water jacket 51 are drawn and joined to the outer peripheral portion of the exhaust pipe 7, and a cooling water passage 52 for circulating cooling water is provided between the water jacket 51 and the exhaust pipe 7. Is formed.

  An inlet pipe 53 for introducing cooling water into the cooling water passage 52 and a discharge pipe 54 for discharging cooling water from the cooling water passage 52 are attached to the upper portion of the water jacket 51. The introduction pipe 53 and the discharge pipe 54 are attached to the water jacket 51 so as to penetrate the peripheral wall of the water jacket 51.

  The introduction pipe 53 is connected to the pipe 28, and the discharge pipe 54 is connected to the pipe 29. For this reason, when the warm cooling water of the heat storage tank 22 is supplied to the cooling water passage 52 through the pipe 28 as the water pump 23 is driven, the exhaust pipe 7 and the water jacket 51 are heated, and the low temperature is passed from the radiator 24 through the pipe 28. When the cooling water is supplied to the cooling water passage 52, the heat of the exhaust gas is recovered into the cooling water and the exhaust gas is cooled.

  On the other hand, the air assist mechanism 35 blows auxiliary compressed air stored in the heat storage tank 22 in addition to high-pressure exhaust gas discharged from the cylinder of the engine 2 to the turbine wheel 6. The heat storage tank 22 is also used as a pressure storage tank.

That is, the collecting pipe 3 a of the exhaust manifold 3 and the heat storage tank 22 are connected by a pipe 36 as an exhaust gas circulation member, and an electromagnetic on-off valve 37 is provided in the middle of the pipe 36. The on-off valve 37 opens and closes the exhaust gas flow passage of the pipe 36 based on a command signal from the ECU 100.
An electromagnetic on-off valve 38 is provided in the middle of the exhaust pipe 7 on the downstream side of the turbine wheel 6, and this on-off valve 38 opens and closes the exhaust passage of the exhaust pipe 7 based on a command signal from the ECU 100. It is like that. In the present embodiment, the on-off valve 37 constitutes a first on-off means, and the on-off valve 38 constitutes a second on-off means.

FIG. 5 is a block diagram of the control circuit of the vehicle 1.
As shown in FIG. 1, the intake pipe 13 is provided with an electronically controlled throttle valve 101 for adjusting the intake air amount in conjunction with the accelerator pedal. The opening of the throttle valve 101 is detected by a throttle opening sensor 102, and detection information of the throttle opening sensor 102 is output to the ECU 100.

  Further, a crank angle sensor 103 that outputs a signal corresponding to the rotation speed of the engine 2 from rotation of the crankshaft in a predetermined angle unit is provided in the vicinity of the crankshaft. Information detected by the crank angle sensor 103 is sent to the ECU 100. It is output.

  As shown in FIG. 1, an air flow meter 104 is provided on the downstream side of the air cleaner 14, and the air flow meter 104 detects the intake air amount and outputs detection information to the ECU 100. .

  Further, the vehicle 1 is provided with a G sensor 105. The G sensor 105 outputs a detection signal corresponding to the acceleration in the longitudinal direction of the vehicle. When deceleration is occurring, a negative output signal is output to ECU 100, respectively. The ECU 100 is configured to determine one of acceleration, deceleration, and constant speed travel of the vehicle 1 based on output information from the G sensor 105.

  The pipe 29 is provided with a water temperature sensor 106, and the water temperature sensor 106 detects the temperature of the cooling water flowing in the pipe 29 and outputs detection information to the ECU 100.

  The ECU 100 is configured as a microcomputer centering on a CPU (not shown). In addition to the CPU, the ECU 100 includes a ROM for storing a processing program such as a warm-up control processing program, a RAM for temporarily storing data, an input / output port, and the like. It is configured to include.

  The ECU 100 performs opening / closing control of the opening / closing valve 37 and the opening / closing valve 38 based on detection information from the throttle opening detection sensor 102, the crank angle sensor 103, the air flow meter 104, and the G sensor 105 during operation of the engine 2. As a result, the exhaust gas is accumulated from the exhaust manifold 3 to the empty heat storage tank 22 through the pipe 36, or the exhaust gas accumulated in the heat storage tank 22 is blown to the turbine wheel 6 through the pipe 36 and the exhaust manifold 3. Is supposed to do.

  Further, the ECU 100 according to the present embodiment sets the valve body of the three-way solenoid valve 34 to the first when the cooling water temperature reaches a predetermined temperature (for example, 80 ° C.) based on the detection information from the water temperature sensor 106. By switching to the communication position, the first port 34a and the second port 34b are communicated, and the communication between the second port 34b and the third port 34c is cut off, so that the radiator 24 and the pipe 29 are connected via the pipe 30. The cooling water discharged from the pipe 29 by cooling the exhaust system parts is supplied to the radiator 24 through the pipe 30 to be cooled, and then supplied to the exhaust system parts.

  In addition, detection information from the door key sensor 107 and the ignition switch 108 is input to the ECU 100. The door key sensor 107 detects unlocking and locking of the door lock mechanism that locks the door of the vehicle 1. When the door lock mechanism is unlocked, the door key sensor 107 outputs an ON signal to the ECU 100. When locked, an off signal is output to the ECU 100.

  Further, the ignition switch 108 outputs an ON signal to the ECU 100 when the engine 2 is started by the ignition key, and outputs an OFF signal to the ECU 100 when the engine 2 is stopped by the ignition key. It is like that.

  The ECU 100 switches the valve body of the three-way solenoid valve 33 to the first communication position and the valve of the three-way solenoid valve 34 before the engine 2 is started when an ON signal is input from the door key sensor 107 when the engine 2 is stopped. By driving the water pump 23 with the body switched to the second communication position, the warm cooling water stored in the heat storage tank 22 is supplied to the exhaust system components.

  The ECU 100 determines whether the engine 2 is stopped and operating based on detection information from the throttle opening detection sensor 102, the crank angle sensor 103, the air flow meter 104, the G sensor 105, the water temperature sensor 106, and the ignition switch 108. .

In the present embodiment, the throttle opening sensor 102, the crank angle sensor 103, the air flow meter 104, the G sensor 105, the water temperature sensor 106, and the ignition switch 108 constitute an operating state detecting means for detecting the operating state of the engine 2, and the ECU 100 Constitutes the cooling water control means.
Further, the ECU 100 determines whether or not the boarding condition is satisfied based on the input signal from the door key sensor 107. When the on signal is input from the door key sensor 107, the boarding condition is satisfied. It comes to judge.
In the present embodiment, the door key sensor 107 and the ECU 100 constitute a boarding condition determination unit. Further, in the present embodiment, the ECU 100 constitutes an opening / closing control means for performing opening / closing control of the opening / closing valve 37 and the opening / closing valve 38.

  Next, the operation will be described based on the flowcharts of FIGS. FIG. 6 is a flowchart showing a processing procedure of the warm-up control program executed by the CPU of the ECU 100, and FIG. 7 is a flowchart showing a processing procedure of the air assist control processing program.

  In FIG. 6, first, the CPU of the ECU 100 (hereinafter simply referred to as CPU) determines whether or not the engine 2 is in operation (step S1). The CPU determines whether or not the engine 2 is in operation based on detection signals from the throttle opening sensor 102, the crank angle sensor 103, the air flow meter 104, the G sensor 105, the water temperature sensor 106, and the ignition switch 108.

  For example, when a crank angle signal corresponding to the rotation speed of the engine 2 is input from the crank angle sensor 103, the CPU determines that the engine 2 is in operation and moves the process to step S8.

  When determining that the engine 2 is stopped in step S1, the CPU determines whether or not the door lock mechanism is unlocked (step S2). When the CPU receives an ON signal from the door key sensor 107, the CPU determines that the door lock mechanism is unlocked, controls the switching of the three-way solenoid valves 33 and 34, and drives the water pump 23 (step S3). ).

  That is, the CPU outputs a command signal to the three-way solenoid valve 33 to switch the valve body of the three-way solenoid valve 33 to the first communication position, thereby communicating the first port 33a and the second port 33b with the valve body. At the same time, the communication between the second port 33b and the third port 33c is cut off, so that the piping 25 and the piping 26 are communicated.

  The CPU outputs a command signal to the three-way solenoid valve 34 to switch the valve body of the three-way solenoid valve 34 to the second communication position, thereby blocking communication between the first port 34a and the second port 34b. The pipe 29 and the bypass pipe 32 are communicated by communicating the second port 34b and the third port 34c.

  In this state, the CPU outputs a command signal to the water pump 23 to drive the water pump 23, whereby the exhaust manifold 3, the pipe 27, the turbine housing 5, the pipe 28, the heat exchanger 9, Warm cooling water stored in the heat storage tank 22 is circulated in the order of the piping 29 and the bypass piping 32.

  Next, the CPU determines whether or not a predetermined time has elapsed since the water pump 23 was driven (step S4). If it is determined that the predetermined time has elapsed, the heat storage tank 22 is emptied. And switching control of the three-way solenoid valve 33 is performed (step S5). This predetermined time is set to a time when the heat storage tank 22 becomes sufficiently empty.

  That is, the CPU outputs a command signal to the three-way solenoid valve 33 to switch the valve body of the three-way solenoid valve 33 to the second communication position, thereby communicating the second port 33b and the third port 33c with the valve body. At the same time, the communication between the first port 33a and the second port 33b is blocked, thereby blocking the pipe 26 and the pipe 25.

  For this reason, the cooling water does not return to the heat storage tank 22, but the warm cooling water is connected to the pipe 26, the exhaust manifold 3, the pipe 27, the turbine housing 5, the pipe 28, the heat exchanger 9, the pipe 29, the bypass pipe 32 and the pipe 26. Circulate. At this time, the water pump 23 may be stopped to retain the cooling water.

  Next, the CPU determines whether or not the ON signal has been input from the ignition switch 108 (step S6). If it is determined that the ON signal has been input, it is determined that the engine 2 has been started. Then, an air assist permission flag is set (step S7).

  This air assist permission flag is a flag indicating that the heat storage tank 22 is emptied and the exhaust gas can be accumulated when the air assist control process is performed. The air assist permission flag is stored in the storage area of the ECU 100 RAM.

  Next, the CPU determines whether or not the temperature of the cooling water is 80 ° C. or higher based on the detection information from the water temperature sensor 106 (step S8). If the CPU determines that the water temperature is less than 80 ° C., it moves the process to step S5, and if it determines that the water temperature is 80 ° C. or higher, it performs switching control of the three-way solenoid valve 34 ( Step S9).

  That is, the CPU outputs a command signal to the three-way solenoid valve 34 to switch the valve body of the three-way solenoid valve 34 to the first communication position so that the first port 34a and the second port 34b communicate with each other, and the second port By blocking communication between 34 b and the third port 34 c, the radiator 24 and the pipe 29 are connected via the pipe 30.

  Therefore, the exhaust manifold 3, the turbine housing 5 and the exhaust pipe 7 are cooled by the low-temperature cooling water, and the cooling water discharged from the pipe 29 is supplied to the radiator 24 via the pipe 29 and the pipe 30. The cooling water is cooled by the radiator 24 and discharged from the pipe 31, and then supplied again to the exhaust manifold 3, the turbine housing 5 and the exhaust pipe 7. For this reason, the exhaust manifold 3, the turbine housing 5 and the exhaust pipe 7 that are heated to a high temperature by the high-temperature exhaust gas are cooled.

  In addition, the cooling water flowing through the heat exchanger 9 is heat-exchanged with the high-temperature exhaust gas flowing through the exhaust pipe 7, and the air blown to the heat exchanger 9 is heated, so that the indoor temperature is increased so that the indoor temperature becomes high. Can be adjusted.

  Further, the CPU determines whether or not an off signal is input from the ignition switch 108 (step S10), and if it is determined that no off signal is input from the ignition switch 108, the process proceeds to step S8. If it is determined that the off signal is input from the ignition switch 108, the air assist permission flag stored in the storage area of the RAM is reset (step S11).

Next, the CPU executes a heat storage heat treatment for the cooling water (step S12). That is, the CPU outputs a command signal to the three-way solenoid valve 33 to switch the valve body of the three-way solenoid valve 33 to the first communication position, thereby communicating the first port 33a and the second port 33b with the valve body. .
In addition, the CPU communicates the second port 34b and the third port 34c by outputting a command signal to the three-way solenoid valve 34 and switching the valve body of the three-way solenoid valve 34 to the second communication position.
Then, by outputting a command signal to the water pump 23 to drive the water pump 23 in the reverse direction, the heated cooling water upstream of the water pump 23 is returned to the heat storage tank 22 through the pipe 26 and the pipe 25, and the heat storage tank 22 When a sufficient amount of high-temperature cooling water is stored, the communication between the second port 33b and the third port 33c is blocked, thereby connecting the pipe 25 and the pipe 26. CPU complete | finishes a warm-up control process, if this thermal storage heat processing is complete | finished.

Next, the air assist control process will be described based on the flowchart of FIG.
In FIG. 7, the CPU determines whether or not the air assist permission flag is set (step S21). When the CPU determines that the air assist permission flag is not set, the CPU determines that the cooling water is stored in the heat storage tank 22 and ends the current process.

  When determining that the air assist permission flag is set, the CPU determines whether or not the air assist permission flag is reset (step S22). The air assist permission flag is reset by the process of step S11 in FIG. 6, and when the CPU determines that the air assist permission flag is not reset, the air assist is being executed. Determination is made and the process proceeds to step S23.

  When the CPU determines that the air assist permission flag has been reset, the CPU determines that the cooling water needs to be returned to the heat storage tank 22 and opens the on-off valve 37 and the on-off valve 38 ( Step S25). For this reason, the exhaust gas accumulated in the heat storage tank 22 is discharged through the pipe 36 and the exhaust manifold 3, and the heat storage tank 22 becomes empty so that the cooling water can be received.

  In step S23, the CPU determines whether the vehicle 1 is traveling at a constant speed or whether the engine 2 is under a high load. That is, if the CPU determines that the vehicle 1 is neither accelerated traveling nor decelerated based on the detection information from the G sensor 105, the CPU determines that the vehicle 1 is traveling at a low speed.

  In addition, based on the detection information from the throttle opening sensor 102, the crank angle sensor 103, and the air flow meter 104, the CPU has a large throttle opening sensor 102, a high crank angle rotation speed, or a large intake air amount. It is determined that the engine 2 is traveling at a high load.

  When the CPU determines that the vehicle 1 is traveling at a constant speed or traveling at a high load of the engine 2, the CPU closes the on-off valve 37 and opens the on-off valve 38 (step S24). Exhaust gas exhausted from the engine 2 is discharged to the catalyst 8 through the exhaust manifold 3 and the exhaust pipe 7.

  At this time, the turbine wheel 6 is rotated by the energy of the exhaust gas, and the rotation of the turbine wheel 6 is transmitted to the compressor wheel 15 via the wheel shaft 16, whereby the air sucked through the air cleaner 14 is compressed. And is supplied to the engine 2 through the intake manifold 10.

  On the other hand, if the CPU determines in step S23 that the vehicle 1 is not traveling at a constant speed or the engine 2 is traveling at a high load, whether the vehicle 1 is decelerating based on detection information from the G sensor 105. It is determined whether or not (step S26).

  When a negative output signal is input from the G sensor 105, the CPU determines that the vehicle is decelerating, opens the on-off valve 37, and closes the on-off valve 38 (step S27). For this reason, the exhaust gas exhausted from the exhaust manifold 3 is stored in the heat storage tank 22 through the pipe 36.

  When the CPU determines that the vehicle is not decelerating in step S26, the CPU determines that the vehicle is accelerating because the positive output signal is being input from the G sensor 105. Is opened and the on-off valve 38 is closed (step S28). For this reason, the exhaust gas accumulated in the heat storage tank 22 is discharged through the pipe 36 and the exhaust manifold 3, and the high-speed exhaust gas discharged from the engine 2 and the exhaust gas (auxiliary compressed air) in the heat storage tank 22 are turbines. The air is applied to the supercharger 4 by being blown onto the wheel 6.

  As described above, in the present embodiment, when the engine 2 is stopped, that is, when the vehicle door is unlocked before the engine 2 is started, the warm cooling water stored in the heat storage tank 22 is used as the exhaust manifold. 3. By supplying the exhaust system parts including the turbine housing 5, the exhaust pipe 7 and the heat exchanger 9, the exhaust system parts in a cooled state before the engine 2 is started can be heated with warm cooling water.

For this reason, after the engine 2 is started, the heat of the exhaust gas discharged from the engine 2 is not easily taken away by the exhaust system parts, and the catalyst 8 can be raised to the activation temperature at an early stage. Can be carried out effectively.
In particular, when increasing or decreasing the fuel injection amount to supply the oxygen by lean combustion and the combustible component (CO (carbon monoxide), etc.) by rich combustion to promote warm-up of exhaust gas, Since the heat of the exhaust gas is not taken away by the system parts, the catalyst 8 can be warmed up more efficiently by such fuel injection control.

  Further, in the present embodiment, by supplying warm cooling water to the exhaust system parts during operation of the engine 2, when the heat storage tank 22 is in an empty state, the exhaust gas is accumulated in the heat storage tank 22, Since the air assist is performed by blowing the exhaust gas accumulated in the heat storage tank 22 to the turbine wheel 6, the single heat storage tank 22 is used for heat storage of the heated cooling water and the pressure accumulation of the exhaust gas. The tank can be used in combination, and the space for mounting the heat storage tank 22 can be reduced to improve the supercharging characteristics.

  In the present embodiment, since the cooling water is circulated through the radiator 24 during the operation of the engine 2, the exhaust system components can be cooled by the low-temperature cooling water, and the exhaust gas is discharged by the high-temperature exhaust gas. It is possible to prevent the system parts from becoming hot. For this reason, it is not necessary to configure the exhaust system parts from expensive heat-resistant materials, and it is possible to prevent an increase in the manufacturing cost of the exhaust system parts.

  Further, since the cooling water is circulated through the radiator 24 during the operation of the engine 2, the heat storage tank 22 can be emptied, and the exhaust gas is stored in the heat storage tank 22 for air assist. It can be used reliably as an accumulator tank.

  In the present embodiment, the ECU 100 determines whether or not the boarding condition is satisfied based on the input signal from the door key sensor 107. As the boarding condition determining means, for example, a pressure is applied to the driver's seat. A sensor may be provided to detect that the driver is sitting in the driver's seat with a pressure sensor, and the ECU 100 may determine whether or not the boarding condition is satisfied based on detection information of the pressure sensor.

  In addition, an optical sensor or the like is provided in front of the driver's seat, the driver detects that the driver is sitting in the driver's seat, and the ECU 100 determines whether or not the boarding condition is satisfied based on the detection information of the optical sensor. May be.

In the present embodiment, a cooling water supply path for supplying cooling water only to the exhaust system components is shown. However, a supply path for supplying cooling water to a water pump or the like provided in a cylinder block of the engine 2 You may make it use together. In this way, the engine 2 can be warmed up early in addition to the exhaust system components.
Further, in this embodiment, the exhaust system component is constituted by the exhaust manifold 3 separate from the engine 2, but the engine 2 has a cylinder head integrated with the exhaust manifold, and the cylinder head integrated with the exhaust manifold. A cooling water flow structure as shown in FIG. 2 may be provided in the exhaust manifold portion, and the exhaust manifold portion may be constituted by exhaust system parts.

In this embodiment, warm cooling water is supplied to all of the exhaust manifold 3, the supercharger 4, the exhaust pipe 7, and the heat exchanger 9. For example, only the exhaust manifold 3 and the turbine housing 5 are cooled. Water may be supplied. That is, warm cooling water may be supplied to any exhaust system component of the exhaust manifold 3, the supercharger 4, the exhaust pipe 7, and the heat exchanger 9.
In the present embodiment, a part of the exhaust pipe 7 is cooled by the heat exchanger 9 provided in the middle of the exhaust pipe 7, and this heat exchanger 9 is arranged along the extending direction of the exhaust pipe 7. All of the exhaust pipe 7 may be cooled by providing them. A plurality of heat exchangers 9 may be provided along the extending direction of the exhaust pipe 7.

  The embodiment disclosed this time is illustrative in all respects and is not limited to this embodiment. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims for patent.

  As described above, the catalyst warm-up control system according to the present invention has an effect that the early warm-up of the catalyst can be effectively performed, and the catalyst warm-up includes the heat storage tank that stores the heated cooling water. Useful as a control system.

1 is a diagram showing an embodiment of a catalyst warm-up control system according to the present invention, and is a schematic configuration diagram of a vehicle equipped with a catalyst warm-up control system. It is a figure which shows one Embodiment of the catalyst warm-up control system which concerns on this invention, and is principal part sectional drawing of an exhaust manifold. It is a figure which shows one Embodiment of the catalyst warm-up control system which concerns on this invention, and is sectional drawing of a supercharger. It is a figure which shows one Embodiment of the catalyst warm-up control system which concerns on this invention, and is sectional drawing of a heat exchanger. 1 is a diagram showing an embodiment of a catalyst warm-up control system according to the present invention, and is a block diagram of a vehicle control circuit. FIG. It is a figure which shows one Embodiment of the catalyst warm-up control system which concerns on this invention, and is a flowchart which shows the process sequence of a warm-up control program. It is a figure which shows one Embodiment of the catalyst warm-up control system which concerns on this invention, and is a flowchart which shows the process sequence of an air assist control processing program.

Explanation of symbols

1 vehicle 2 engine (internal combustion engine)
3 Exhaust manifold (exhaust system parts)
5 Turbine housing (exhaust system parts)
6 Turbine wheel 7 Exhaust pipe (exhaust system parts)
8 Catalyst 9 Heat exchanger (exhaust system parts)
21 catalyst warm-up control system 22 heat storage tank 23 water pump (cooling water supply means, cooling water circulation means)
24 Radiator (heat exchange means)
25 Piping (cooling water supply means)
26, 27, 28, 29, 30, 31 Piping (cooling water circulation means)
32 Bypass piping (cooling water circulation means)
33 Three-way solenoid valve (cooling water supply means, cooling water circulation means)
34 Three-way solenoid valve (cooling water circulation means)
37 On-off valve (first opening / closing means)
38 On-off valve (second on-off means)
100 ECU (cooling water control means, opening / closing control means, boarding condition determination means)
102 Throttle opening sensor (operating state detection means)
103 Crank angle sensor (operating state detecting means)
104 Air flow meter (Operating state detection means)
105 G sensor (operating state detection means)
106 Water temperature sensor (operating state detection means)
107 door key sensor (boarding condition judging means)
108 Ignition switch (Operating state detection means)

Claims (3)

Catalyst warm-up control for warming up the catalyst by heating an exhaust system component provided in an exhaust gas exhaust path between the internal combustion engine and a catalyst for purifying exhaust gas exhausted from the internal combustion engine A system,
A heat storage tank for storing heated cooling water;
Cooling water circulating means for circulating cooling water to the exhaust system parts;
Cooling water supply means for supplying cooling water stored in the heat storage tank to the cooling water circulation means;
An operating state detecting means for detecting an operating state of the internal combustion engine;
Boarding condition determination means for determining whether or not a predetermined boarding condition is satisfied;
The cooling water supply means is activated when it is detected that the internal combustion engine is stopped based on the operating state detection means and the boarding condition determination means determines that the boarding conditions are satisfied. And a cooling water control means for supplying the cooling water stored in the heat storage tank to the cooling water circulation means. The exhaust system component communicates at least with an exhaust port of the internal combustion engine, and is configured to house an exhaust manifold constituting the exhaust system component and a turbine wheel that is provided downstream of the exhaust manifold and is rotated by exhaust gas. A turbocharger with a housing,
An exhaust gas circulation member having an exhaust gas circulation passage for flowing an exhaust gas between the exhaust manifold and the heat storage tank, a first opening / closing means for opening and closing the exhaust gas circulation passage, and a downstream side of the turbine wheel A second opening / closing means for opening / closing the exhaust passage; and an opening / closing control means for performing opening / closing control of the first opening / closing means and the second opening / closing means based on detection information from the operating state detecting means. The catalyst warm-up control system according to claim 1. Comprising heat exchange means for performing heat exchange of the cooling water flowing through the cooling water member,
3. The catalyst warm-up according to claim 2, wherein the cooling water control unit circulates the cooling water circulating through the cooling water circulation unit through the heat exchange unit based on detection information from the operating state detection unit. Machine control system.

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