JP2022053989A - Engine device - Google Patents

Abstract

To prevent the temperature of a supercharger or its ambient temperature from rising after stopping an engine.SOLUTION: In a case where a system is turned off without a drive request for an electric pump of a cooling device that cools a supercharger and its surroundings, when there is no drive request for the electric pump when a predetermined period has elapsed since the system was turned off, a main relay is turned off at predetermined timing after the predetermined period has elapsed. On the other hand, when there is a drive request for the electric pump when the predetermined period has elapsed since the system was turned off, the main relay is turned off at predetermined timing after the drive request for the electric pump disappears.SELECTED DRAWING: Figure 4

Description

The present invention relates to an engine device, and more particularly to an engine device including an engine having a supercharger.

Conventionally, this type of engine device includes a cooling device having an intercooler attached to an intake pipe after the supercharger of an engine with a supercharger and a radiator for cooling the cooling water supplied to the intercooler. Has been proposed (see, for example, Patent Document 1). In the cooling device of this engine device, the supercharger and the intake air are cooled by being cooled by the radiator and pumping cooling water by an electric pump to supply the turbocharger to the turbine housing and the intercooler.

Japanese Unexamined Patent Publication No. 2013-092131

Generally, when the electric pump of the cooling device is driven when the system is turned off, the connection of the main relay is secured until the drive request of the electric pump disappears, but when the system is turned off, the electric pump of the cooling device is driven. When not, that is, when there is no drive request for the electric pump, confirm that the rotation of the engine is stopped and turn off the main relay. Since the temperature rise in the turbocharger and its surroundings is delayed with respect to the engine operation, the temperature in the turbocharger and its surroundings may rise even after the engine is stopped.

An object of the engine device of the present invention is to cope with an event in which the temperature of the turbocharger and its surroundings rises after the engine is stopped.

The engine device of the present invention has adopted the following means in order to achieve the above-mentioned main object.

The engine device of the present invention
An engine having a supercharger, a cooling device having a heat exchanger for cooling the intake and / or the supercharger in the subsequent stage of the supercharger, and an electric pump for pumping a cooling medium to the heat exchanger, and the electric motor. Controls a power storage device that supplies power to a pump and auxiliary equipment, a main relay attached to a power line connecting the power storage device, the electric pump, and the auxiliary equipment, and the engine, the cooling device, and the main relay. An engine device equipped with a control device for
When the control device is turned off without a drive request for the electric pump,
(1) If there is no drive request for the electric pump when a predetermined period has elapsed since the system was turned off, the main relay is turned off at a predetermined timing after the predetermined period has elapsed.
(2) When there is a drive request for the electric pump when the predetermined period has elapsed since the system was turned off, the main relay is turned off at a predetermined timing after the drive request for the electric pump disappears.
It is characterized by that.

In the engine device of the present invention, when the system is turned off without a drive request for the intake air in the subsequent stage of the turbocharger or the electric pump of the cooling device for cooling the supercharger, the engine is electrically operated when a predetermined period has elapsed since the system was turned off. When there is no request to drive the pump, the main relay is turned off at a predetermined timing after the lapse of a predetermined period. On the other hand, when the system is turned off without a drive request for the electric pump, and when there is a drive request for the electric pump when a predetermined period has elapsed since the system was turned off, at a predetermined timing after the drive request for the electric pump disappears. Turn off the main relay. That is, even after the system is turned off, when there is a demand to drive the electric pump, the electric pump is driven to supply a cooling medium to the heat exchanger to cool the supercharger and its surroundings, and this cooling is used to cool the electric pump. When the drive request disappears, the electric pump is stopped, and then the main relay is turned off. This makes it possible to deal with the event that the temperature of the turbocharger and its surroundings rises after the engine is stopped.

Here, as the "predetermined period", a period until it is confirmed that the rotation of the engine is stopped or a predetermined time in consideration of this can be used. Further, as the "predetermined timing", the timing at which a sufficient time (sufficient time for the rotation of the electric pump to stop) has elapsed for the counter electromotive force of the electric pump to reach a value of 0, or a predetermined timing in consideration of this. The timing at which time has passed can be used.

It is a block diagram which shows the outline of the structure of the engine apparatus 10 as an Example of this invention. It is a block diagram which shows the outline of the structure of the cooling device 60 incorporated in the engine device 10. It is explanatory drawing which shows an example of the input / output signal of the electronic control unit 70 incorporated in the engine apparatus 10. It is a flowchart which shows an example of the ignition off processing executed by an electronic control unit 70. It is a timing chart which shows an example of the state of an ignition switch and an engine at the time of ignition off, a flag Feg after a start, a drive request of an electric water pump 64, and a state of a main relay 52.

Next, an embodiment for carrying out the present invention will be described with reference to examples.

FIG. 1 is a configuration diagram showing an outline of the configuration of an engine device 10 as an embodiment of the present invention. FIG. 2 is a configuration diagram showing an outline of the configuration of the cooling device 60 incorporated in the engine device 10. FIG. 3 is an explanatory diagram showing an example of an input / output signal of the electronic control unit 70 incorporated in the engine device 10. The engine device 10 of the embodiment is mounted on a general automobile or various hybrid automobiles, and as shown in FIGS. 1 to 3, the engine 12, the supercharger 40, the intercooler 25, and the cooling device 60 are included. , With an electronic control unit 70.

The engine 12 is configured as an internal combustion engine that outputs power using fuel such as gasoline or light oil supplied from the fuel tank 11 via a feed pump or a fuel passage (not shown). The engine 12 sucks the air cleaned by the air cleaner 22 into the intake pipe 23 and passes it through the intercooler 25, the throttle valve 26, and the surge tank 27 in this order, and injects fuel on the downstream side of the surge tank 27 of the intake pipe 23. Fuel is injected from the valve 28 to mix the air and the fuel. The engine 12 sucks this air-fuel mixture into the combustion chamber 30 through the intake valve 29, and explodes and burns it by electric sparks from the spark plug 31. The engine 12 converts the reciprocating motion of the piston 32 pushed down by the energy generated by such explosive combustion into the rotational motion of the crankshaft 14. The exhaust gas discharged from the combustion chamber 30 to the exhaust pipe 35 via the exhaust valve 34 is a catalyst (three-way catalyst) that purifies harmful components of carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx). ) Is discharged to the outside air through the purification devices 37 and 38.

The turbocharger 40 is configured as a turbocharger and includes a compressor 41, a turbine 42, a rotary shaft 43, a wastegate valve 44, and an air bypass valve 45. The compressor 41 is arranged on the upstream side of the intercooler 25 of the intake pipe 23. The turbine 42 is arranged on the upstream side of the purification device 37 of the exhaust pipe 35. The rotary shaft 43 connects the compressor 41 and the turbine 42. The wastegate valve 44 is provided in the bypass pipe 36 connecting the upstream side and the downstream side of the turbine 42 in the exhaust pipe 35, and is controlled by the electronic control unit 70. The air bypass valve 45 is provided in the bypass pipe 24 connecting the upstream side and the downstream side of the compressor 41 in the intake pipe 23, and is controlled by the electronic control unit 70.

In the turbocharger 40, by adjusting the opening degree of the wastegate valve 44, the distribution ratio between the displacement flowing through the bypass pipe 36 and the displacement flowing through the turbine 42 is adjusted, and the rotational driving force of the turbine 42 is adjusted. Then, the amount of compressed air by the compressor 41 is adjusted, and the supercharging pressure (intake pressure) of the engine 12 is adjusted. Here, in detail, the distribution ratio is adjusted so that the smaller the opening degree of the wastegate valve 44, the smaller the displacement flowing through the bypass pipe 36 and the larger the displacement flowing through the turbine 42. When the wastegate valve 44 is fully opened, the engine 12 can operate in the same manner as a naturally aspirated type engine without a supercharger 40. Further, the wastegate valve 44 is configured as a check valve that opens when the pressure of the exhaust pipe 35 becomes to some extent higher than the pressure downstream of the turbine 42, instead of the valve controlled by the electronic control unit 70. May be good.

Further, in the turbocharger 40, when the pressure on the downstream side of the intake pipe 23 on the downstream side of the compressor 41 is higher than the pressure on the upstream side to some extent, the air bypass valve 45 is opened to the downstream side of the compressor 41. Excess pressure can be released. The air bypass valve 45 is a check valve that opens when the pressure on the downstream side of the compressor 41 in the intake pipe 23 becomes higher than the pressure on the upstream side to some extent, instead of the valve controlled by the electronic control unit 70. It may be configured.

The intercooler 25 is arranged on the downstream side of the compressor 41 of the intake pipe 23. A cooling medium (for example, long life coolant (LLC)) from the cooling device 60 circulates in the intercooler 25. The intercooler 25 cools the air (intake) in the intake pipe 23 by exchanging heat between the air (intake) in the intake pipe 23 and the cooling medium (cooling water in the embodiment) from the cooling device 60.

The cooling device 60 supplies a cooling medium (cooling water in the embodiment) to a water jacket or an intercooler 25 (not shown) of the supercharger 40 to cool the supercharger 40 and its surroundings. As shown in FIG. 2, the cooling device 60 includes a refrigerant flow path 62, an electric water pump 64, and a radiator 66. The refrigerant flow path 62 is configured such that the intercooler 25 and the water jacket of the turbocharger 40 circulate the cooling water in parallel. The electric water pump 64 is controlled by an electronic control unit 70, and pumps cooling water to the refrigerant flow path 62. The radiator 66 cools the cooling water by exchanging heat between the cooling water and air. The electric water pump 64 is supplied with electric power from a power line 52 connected to the battery 50 via a main relay. Various auxiliary machines 56 are also connected to the power line 52.

The electronic control unit 70 is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port in addition to the CPU. Signals from various sensors are input to the electronic control unit 70 via the input port.

The signals input to the electronic control unit 70 include, for example, a crank angle θcr from the crank position sensor 14a that detects the rotational position of the crankshaft 14 of the engine 12, and a water temperature (not shown) that detects the temperature of the cooling medium of the engine 12. Examples include the temperature Tw of the cooling medium from the sensor and the throttle opening TH from the throttle position sensor 26a that detects the opening degree of the throttle valve 26. Camposition θca from a camposition sensor (not shown) that detects the rotational position of the intake camshaft that opens and closes the intake valve 29 and the exhaust camshaft that opens and closes the exhaust valve 34 can also be mentioned. The intake air amount Qa from the air flow meter 23a attached to the upstream side of the compressor 41 of the intake pipe 23, the intake pressure Pin from the pressure sensor 23b attached to the upstream side of the compressor 41 of the intake pipe 23, and the intake pipe. The boost pressure Pc from the pressure sensor 23c installed between the compressor 41 of the 23 and the intercooler 25, and the intake air temperature Tin from the temperature sensor 23d installed upstream of the compressor 41 of the intake pipe 23 are also listed. Can be done. Surge pressure Ps from the pressure sensor 27a attached to the surge tank 27 and surge temperature Ts from the temperature sensor 27b attached to the surge tank 27 can also be mentioned. The front air-fuel ratio AF1 from the front air-fuel ratio sensor 35a installed on the upstream side of the purification device 37 of the exhaust pipe 35, and the rear air-fuel ratio sensor installed between the purification device 37 and the purification device 38 of the exhaust pipe 35. The rear air-fuel ratio AF2 from 35b can also be mentioned. Further, the ignition signal IG from the ignition switch 80, the shift position SP from the shift position sensor 82 that detects the operation position of the shift lever 81, and the accelerator opening degree from the accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83. Acc, the brake pedal position BP from the brake pedal position sensor 86 that detects the depression amount of the brake pedal 85, and the like can also be mentioned.

Various control signals are output from the electronic control unit 70 via the output port. Examples of the signal output from the electronic control unit 70 include a control signal to the throttle valve 26, a control signal to the fuel injection valve 28, and a control signal to the spark plug 31. A control signal to the wastegate valve 44, a control signal to the air bypass valve 45, a drive control signal to the main relay 54, a drive control signal to the auxiliary machine 56, and a drive control signal to the electric water pump 64 can also be mentioned. ..

The electronic control unit 70 calculates the rotation speed Ne of the engine 12 based on the crank angle θcr from the crank position sensor 14a. Further, the electronic control unit 70 has a load factor (air actually sucked in one cycle with respect to the stroke volume per cycle of the engine 12) based on the intake air amount Qa from the air flow meter 23a and the rotation speed Ne of the engine 12. Volume ratio of) KL is calculated. Further, the electronic control unit 70 has an intake air temperature Tinc on the upstream side of the intercooler 25 based on the intake pressure Pin from the pressure sensor 23b, the boost pressure Pc from the pressure sensor 23c, and the intake air temperature Tin from the temperature sensor 23d. (The temperature of the intake air flowing into the intercooler 25) is calculated.

In the engine device 10 of the embodiment configured in this way, the electronic control unit 70 controls the intake air amount that controls the opening degree of the throttle valve 26 based on the required load factor KL * of the engine 12, and the fuel injection valve 28. Fuel injection control for controlling the fuel injection amount, ignition control for controlling the ignition timing of the ignition plug 31, supercharging control for controlling the opening degree of the wastegate valve 44, and the like are performed. As the intake air amount control, for example, the target intake air amount Qa * is set based on the required load factor KL *, and the target opening degree TH of the throttle valve 26 is set so that the intake air amount Qa becomes the target intake air amount Qa *. * Is set, and the throttle valve 26 is controlled so that the throttle opening TH * becomes the target opening TH *. For fuel injection control, for example, the target fuel injection amount Qf * of the fuel injection valve 28 is set so that the front air-fuel ratio AF1 becomes the target air-fuel ratio AF * (for example, the theoretical air-fuel ratio) based on the intake air amount Qa. , It is performed by controlling the fuel injection valve 28 using the set target fuel injection amount Qf *. As ignition control, for example, the target ignition timing Tf * of the ignition plug 31 is set based on the rotation speed Ne of the engine 12 and the required load factor KL *, and the spark plug 31 is controlled using the set target ignition timing Tf *. It is done by doing.

Next, the operation of the engine device 10 of the embodiment, particularly the operation when the ignition switch 80 is turned off will be described. FIG. 4 is a flowchart showing an example of an ignition off process executed by the electronic control unit 70 when the ignition switch 80 is turned off while the engine 12 is being driven.

When the ignition off process is executed, the electronic control unit 70 first stops the driving engine 12 (step S100), and whether or not the electric water pump 64 has a drive request (on or off). Is determined (step S110). When it is determined that the electric water pump 64 has a drive request (on), the electric water pump 64 is being driven and cooled due to the high temperature of the turbocharger 40 and its surroundings. Waiting for the drive request of the electric water pump 64 to disappear (step S140), waiting for a predetermined time to elapse (step S150), turning off the main relay 54 (step S150), and ending the ignition off process. When the drive request of the electric water pump 64 disappears (turns off), the drive of the electric water pump 64 is stopped. Therefore, these processes wait for a predetermined time to elapse after the drive of the electric water pump 64 is stopped, and then the main relay. 54 will be turned off. Here, as the predetermined time, a sufficient time is used for the counter electromotive force generated until the rotation of the electric water pump 64 is stopped becomes a value of 0. By turning off the main relay 54 after waiting for a predetermined time to elapse in this way, it is possible to prevent the main relay 54 from being turned off when the voltage of the power line 52 is higher than the voltage of the battery 50.

When it is determined in step S110 that there is no drive request (off) for the electric water pump 64, that is, when the ignition is turned off while there is no drive request (not driving) for the electric water pump 64, the post-start flag Feg Waits for the value to reach 0 (step S120), and determines whether or not there is a drive request for the electric water pump 64 (on or off) (step S130). The post-start flag Feg is set to a value of 1 when the engine 12 is started, and is set to a value of 0 when it is confirmed that the rotation of the engine 12 has completely stopped. Therefore, the process of waiting for the flag Feg to reach a value of 0 after starting is the process of waiting until it is confirmed that the rotation of the engine 12 is completely stopped. Since the temperature rise in the turbocharger 40 and its surroundings is delayed with respect to the operation of the engine 12, the temperature in the turbocharger 40 and its surroundings may rise even after the engine 12 is stopped. If the temperature of the turbocharger 40 and its surroundings exceeds the threshold value when the flag Feg becomes 0 after starting, a drive request for the electric water pump 64 is made (turned on). When the drive request for the electric water pump 64 is made (turned on), the electric water pump 64 is driven, cooling water is supplied to the supercharger 40 and the intercooler 25, and the supercharger 40 and its surroundings are turned on. It is cooled.

If it is determined in step S130 that there is no drive request (off) for the electric water pump 64, the main relay 54 is turned off (step S150) after waiting for a predetermined time to elapse (step S150), and the ignition off process is completed. do.

When it is determined in step S130 that there is a drive request (on) for the electric water pump 64, it waits for the drive request for the electric water pump 64 to disappear (step S140), and then waits for a predetermined time to elapse (step). S150), the main relay 54 is turned off (step S150), and the ignition off process is completed.

FIG. 5 is a timing chart showing an example of the state of the ignition switch and engine at the time of ignition off, the flag Feg after starting, the drive request of the electric water pump 64, and the state of the main relay 54. In the figure, after the time T3, the solid line is the operation when it is determined that there is a drive request (on) for the electric water pump 64 at the time T3, and the broken line is the operation when it is determined that there is a drive request for the electric water pump 64 at the time T3. This is the operation when it is determined (off). When the ignition switch 80 is turned off at the time T1 while the engine 12 is being driven, the engine 12 is turned off (driving stopped) at the time T21 immediately after that. The flag Feg is turned off after the start at the time T3 when the period required for confirming that the engine 12 has been stopped and the rotation of the engine 12 has completely stopped has elapsed. At this time, it is determined whether or not there is a drive request for the electric water pump 64 (whether it is on or off). When it is determined that there is a drive request (on) for the electric water pump 64, the counter electromotive force of the electric water pump 64 becomes a value 0 from the time T5 when the drive request for the electric water pump 64 disappears (turns off). The main relay 54 is turned off at the time T6 after a predetermined time set as a sufficient time has elapsed. As a result, it is possible to deal with the event that the temperature of the turbocharger 40 and its surroundings rises after the engine 12 is stopped. When it is determined that there is no drive request (off) for the electric water pump 64 at the time T3, the main relay 54 is turned off at the time T4 when a predetermined time has elapsed from the time T3.

In the engine device 10 of the above-described embodiment, when the engine 12 is driven and the ignition is turned off while the electric water pump 64 is stopped, the electric water waits for the flag Feg to reach a value of 0 after starting. It is determined whether or not there is a drive request for the pump 64 (on or off). When it is determined that there is a drive request (on) for the electric water pump 64, the main relay 54 is turned off after waiting for the drive request for the electric water pump 64 to disappear (turn off) and after a predetermined time has elapsed. .. As a result, the electric water pump 64 is driven until the drive request of the electric water pump 64 disappears (turns off), cooling water is supplied to the supercharger 40 and the intercooler 25, and the supercharger 40 and its surroundings are cooled. can do. That is, it is possible to deal with the event that the temperature of the turbocharger 40 and its surroundings rises after the engine 12 is stopped.

In the engine device 10 of the embodiment, the supercharger 40 is configured as a turbocharger in which the compressor 41 arranged in the intake pipe 23 and the turbine 42 arranged in the exhaust pipe 35 are connected via the rotating shaft 43. There is. However, instead of this, a compressor driven by the engine 12 or a motor may be configured as a supercharger arranged in the intake pipe 23.

In the embodiment, the engine device 10 mounted on a general automobile or various hybrid automobiles is used. However, it may be in the form of an engine device mounted on a vehicle other than an automobile, or may be in the form of an engine device mounted on non-moving equipment such as construction equipment.

The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem will be described. In the embodiment, the supercharger 40 corresponds to the "supercharger", the engine 12 corresponds to the "engine", the water jacket of the supercharger 40 and the intercooler 25 correspond to the "heat exchanger", and are electric. The water pump 64 corresponds to the "electric pump", and the cooling device 60 corresponds to the "cooling device". Further, the battery 50 corresponds to the "power storage device", the auxiliary machine 56 corresponds to the "auxiliary machine", the power line 52 corresponds to the "power line", the main relay 54 corresponds to the "main relay", and the electronic device is used. The control unit 70 corresponds to a "control device".

As for the correspondence between the main elements of the examples and the main elements of the invention described in the column of means for solving the problem, the invention described in the column of means for solving the problems of the examples is carried out. Since it is an example for specifically explaining the mode for solving the problem, the elements of the invention described in the column of means for solving the problem are not limited. That is, the interpretation of the invention described in the column of means for solving the problem should be performed based on the description in the column, and the examples are the inventions described in the column of means for solving the problem. It is just a concrete example.

Although the embodiments for carrying out the present invention have been described above with reference to the embodiments, the present invention is not limited to these examples, and the present invention is not limited to these embodiments, and various embodiments are used without departing from the gist of the present invention. Of course it can be done.

The present invention can be used in the manufacturing industry of engine devices and the like.

10 internal combustion engine device, 12 engine, 14 crank shaft, 14a crank position sensor, 22 air cleaner, 23 intake pipe, 23a air flow meter, 23b, 23c, 27a pressure sensor, 24, 36 bypass pipe, 25 intercooler, 26 throttle valve, 26a Throttle position sensor, 27 surge tank, 23d, 27b temperature sensor, 28 fuel injection valve, 29 intake valve, 30 combustion chamber, 31 ignition plug, 32 piston, 34 exhaust valve, 35 exhaust pipe, 35a front air fuel ratio sensor, 35b Rear air-fuel ratio sensor, 37,38 purification device, 40 supercharger, 41 compressor, 42 turbine, 43 rotary shaft, 44 waste gate valve, 45 air bypass valve, 50 battery, 52 power line, 54 main relay, 56 auxiliary equipment , 60 cooling device, 62 refrigerant flow path, 64 electric water pump, 66 radiator, 70 electronic control unit, 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 Brake pedal position sensor.

Claims (1)

An engine having a supercharger, a cooling device having a heat exchanger for cooling the intake and / or the supercharger in the subsequent stage of the supercharger, and an electric pump for pumping a cooling medium to the heat exchanger, and the electric motor. Controls a power storage device that supplies power to a pump and auxiliary equipment, a main relay attached to a power line connecting the power storage device, the electric pump, and the auxiliary equipment, and the engine, the cooling device, and the main relay. An engine device equipped with a control device for
When the control device is turned off without a drive request for the electric pump,
(1) If there is no drive request for the electric pump when a predetermined period has elapsed since the system was turned off, the main relay is turned off at a predetermined timing after the predetermined period has elapsed.
(2) When there is a drive request for the electric pump when the predetermined period has elapsed since the system was turned off, the main relay is turned off at a predetermined timing after the drive request for the electric pump disappears.
An engine device characterized by that.

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