JP6244765B2 - Control device for internal combustion engine - Google Patents

Description

  The present invention relates to a control device for an internal combustion engine, and more particularly to a control device for an internal combustion engine that suppresses a decrease in the life of an electromagnetic valve that switches between supply and stop of oil supply to an oil jet.

  2. Description of the Related Art Conventionally, a technique for injecting oil from an oil jet provided in an internal combustion engine toward the piston is known for the purpose of cooling the piston of the internal combustion engine.

  However, this type of internal combustion engine often does not stop the supply of oil to the oil jet even when cooling of the piston is unnecessary, so even when the temperature of the piston immediately after start-up is low, the oil is supplied to the piston. Is injected, there is a risk that the warm-up performance of the internal combustion engine will be reduced.

  Therefore, for example, Patent Document 1 discloses a technique for selecting whether to supply or shut off oil to an oil jet using an electromagnetic valve having a spool valve that reciprocates by cooperation of a solenoid coil and a return spring. ing.

JP 2007-040148 A

  By the way, in recent years, the exhaust gas temperature tends to rise in order to cope with the downsizing of the internal combustion engine and the tightening of exhaust gas regulations, and the ambient temperature in the engine compartment tends to rise accordingly. For this reason, as in the case of the above-mentioned Patent Document 1, in the case of selecting supply or shut-off (supply stop) of oil to the oil jet using a solenoid valve, when the ambient temperature in the engine compartment increases, The temperature may increase. If the solenoid valve is overheated, the life of the solenoid coil inside the solenoid valve is significantly reduced, and the life of the solenoid valve may be reduced.

  The present invention has been made in view of the above points, and an object of the present invention is to provide an electromagnetic valve caused by overheating in a control device for an internal combustion engine including an electromagnetic valve that switches between supply and stop of oil supply to an oil jet. It is in providing the technique which suppresses the fall of the lifetime.

  In order to achieve the above object, in the control device for an internal combustion engine according to the present invention, an increase in the internal temperature of the solenoid valve is suppressed when the ambient temperature around the solenoid valve becomes high.

  Specifically, the present invention provides an internal combustion engine control device comprising: an oil jet that injects oil toward a piston of the internal combustion engine; and an electromagnetic valve that switches between supply and stop of oil supply to the oil jet. It is targeted.

In the control device, the solenoid valve has a solenoid coil and a return spring, and when the voltage applied to the solenoid coil is turned on, the supply of oil to the oil jet is stopped. When the voltage applied to the solenoid coil is turned off, oil is supplied to the oil jet by the urging force of the return spring, and a parameter related to the temperature of the solenoid valve is obtained, When the parameter is greater than or equal to a threshold value, the control of the solenoid valve is prohibited and the voltage applied to the solenoid coil is turned off .

  The “threshold value” in the present invention is a temperature set lower than the temperature obtained by subtracting, for example, the temperature due to self-heating of the solenoid valve generated by applying a voltage to the solenoid valve from the heat resistant limit temperature of the solenoid valve. Alternatively, it may be a value having a correlation with the set temperature.

According to this configuration, when the parameter related to the temperature of the solenoid valve is greater than or equal to the threshold value, the solenoid valve is prohibited from being controlled, so that self-heating of the solenoid valve caused by applying a voltage to the solenoid valve can be suppressed. it can. Thus, since the temperature of the solenoid valve depends on the temperature due to the self-heating of the solenoid valve and the ambient temperature in the engine compartment, for example, the temperature of the solenoid valve is increased by the temperature due to the self-heating of the solenoid valve. Can be suppressed. Therefore, it is possible to suppress the temperature of the solenoid valve from exceeding the heat resistant limit temperature, and it is possible to suppress a decrease in the life of the solenoid valve due to overheating.
In addition, even when the parameter related to the temperature of the solenoid valve exceeds the threshold value and control of the solenoid valve is prohibited, oil is injected from the oil jet toward the piston, which prevents the life of the solenoid valve from being reduced. While the piston can be cooled.

  In addition, according to this configuration, even when electromagnetic valves having different heat-resistant limit temperatures are used, it is possible to cope with the problem by simply changing the threshold value. Therefore, it is possible to suppress a decrease in the life of the electromagnetic valve with a simple configuration.

  Moreover, in the said control apparatus, you may make it use the cooling water temperature of an internal combustion engine as a parameter relevant to the temperature of a solenoid valve. Thus, by using parameters used for other controls such as the cooling water temperature, it is possible to suppress a decrease in the life of the solenoid valve with a simple configuration. When the internal combustion engine includes an oil temperature sensor, the oil temperature may be used as a parameter related to the temperature of the solenoid valve.

  Further, as the solenoid valve, a spool valve that moves to a position where oil is supplied to the oil jet or a supply stop position, a return spring that biases the spool valve to the supply position, and a biasing force of the return spring that resists the application of voltage. Then, a normally open solenoid valve having a solenoid coil for moving the spool valve to the supply stop position may be used. In this way, even when the parameter related to the temperature of the solenoid valve exceeds the threshold value and control of the solenoid valve is prohibited, the spool valve is urged to the supply position, and the oil is directed from the oil jet toward the piston. Since the fuel is injected, the piston can be cooled while suppressing a decrease in the life of the solenoid valve.

  As described above, according to the control apparatus for an internal combustion engine of the present invention, it is possible to suppress a decrease in the life of the electromagnetic valve due to overheating.

It is a figure which shows schematic structure of the engine to which the control apparatus of this invention is applied. It is a block diagram which shows schematic structure of a control system. It is the schematic which shows the state of OSV in a 1st operation mode. It is the schematic which shows the state of OSV in 2nd operation mode. It is the schematic which shows the state of OSV in 3rd operation mode. It is a flowchart which shows an example of the overheat suppression control of OSV. It is a timing chart which shows an example of the overheat suppression control of OSV which ECU performs.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In the present embodiment, the present invention is applied to a direct injection type four-cylinder gasoline engine for automobiles.

-Engine-
FIG. 1 is a diagram showing a schematic configuration of an engine (internal combustion engine) 1 to which a control device of the present invention is applied. FIG. 1 shows only the configuration of one cylinder of the engine 1. As shown in FIG. 1, a piston 3 that reciprocates in the vertical direction is provided in a cylinder block 1 a that constitutes each cylinder of the engine 1. The piston 3 is connected to a crankshaft (not shown) via a connecting rod 2, and the reciprocating motion of the piston 3 is converted by the connecting rod 2 into rotation of the crankshaft.

  A signal rotor (not shown) in which a plurality of protrusions (teeth) are provided at equal angles on the outer peripheral surface is attached to the crankshaft. A crank position sensor 54 (see FIG. 2) is disposed near the side of the signal rotor. The crank position sensor 54 is, for example, an electromagnetic pickup, and generates a pulse signal (output pulse) corresponding to the protrusion of the signal rotor when the crankshaft rotates.

  In the cylinder block 1a, a water jacket 4 through which cooling water circulates is formed so as to surround each cylinder. Further, a water temperature sensor 51 that detects the temperature (engine water temperature) Tw of the cooling water circulating in the water jacket 4 is disposed in the cylinder block 1a. Furthermore, a cylinder head 1 b is provided at the upper end of the cylinder block 1 a, and a combustion chamber 30 is formed between the cylinder head 1 b and the piston 3.

  An intake passage 27 and an exhaust passage 28 are connected to the combustion chamber 30 of the engine 1. In the intake passage 27, an electronically controlled throttle valve (not shown) for adjusting the intake air amount of the engine 1 is disposed. On the other hand, a three-way catalyst (not shown) capable of purifying a three-way component (NOx, HC, CO) contained in the exhaust gas is disposed in the exhaust passage 28. The throttle valve is driven by a throttle motor 57 (see FIG. 2). The opening of the throttle valve is detected by a throttle position sensor 53 (see FIG. 2).

  In the cylinder head 1b, an injector 55 (see FIG. 2) for directly injecting fuel into the combustion chamber 30 and a spark plug (not shown) are arranged for each cylinder. Each injector 55 is supplied with high-pressure fuel, and directly injects the fuel from each injector 55 into the combustion chamber 30 to form an air-fuel mixture in which air and fuel are mixed in the combustion chamber 30. Then, the air-fuel mixture is ignited by the spark plug and burned in the combustion chamber 30, whereby the piston 3 reciprocates and the crankshaft rotates. The operating state of the engine 1 is controlled by an ECU (Electronic Control Unit) 100. Note that the ignition timing of the spark plug is adjusted by an igniter 56 (see FIG. 2).

  A main gallery 5 and an oil jet oil passage 6 are formed below the water jacket 4 in the cylinder block 1a, and oil is directed toward the back surface of each piston 3 (the surface opposite to the combustion chamber 30). Is provided. The main gallery 5 is connected to the oil pump 9 via the first oil supply pipe 11. The oil jet oil passage 6 includes a first oil supply pipe 11, a second oil supply pipe 12 branched from the first oil supply pipe 11, an oil switching valve (hereinafter also referred to as OSV) 10, and a third oil supply pipe 13. And is connected to the oil pump 9. The oil pump 9 is a mechanical oil pump that is rotationally driven by the drive of the engine 1 and sucks up the oil accumulated in the oil pan 8 attached to the lower end of the cylinder block 1a and uses the sucked up oil for the main gallery 5 and the oil jet. Supply by pressure to the oil passage 6.

  The oil supplied from the oil pump 9 to the main gallery 5 through the first oil supply pipe 11 lubricates the lubrication part of the engine 1, then flows down in the cylinder block 1 a and accumulates in the oil pan 8 again. On the other hand, the oil supplied from the oil pump 9 to the oil passage 6 for the oil jet through the first oil supply pipe 11, the second oil supply pipe 12, the OSV 10 and the third oil supply pipe 13 is injected from the oil jet 7. After cooling the piston 3, it flows down in the cylinder block 1 a and accumulates in the oil pan 8 again. In addition, a part of the oil supplied from the oil pump 9 opens the relief valves (the high pressure adjustment valve 18 and the low pressure adjustment valve 19) when the oil pressure of the oil flowing through the first oil supply pipe 11 becomes equal to or higher than a predetermined pressure. Thus, the oil returns to the oil pan 8 through the oil return pipe 14.

-ECU-
FIG. 2 is a block diagram showing a schematic configuration of a control system in the engine 1. As shown in FIG. 2, an ECU (control device) 100 includes a CPU (Central Processing Unit) 101, a ROM (Read Only Memory) 102, a RAM (Random Access Memory) 103, a backup RAM 104, and the like. The ROM 102 stores various control programs, maps that are referred to when the various control programs are executed, and the like. The CPU 101 executes arithmetic processing based on various control programs and maps stored in the ROM 102. The RAM 103 is a memory that temporarily stores calculation results of the CPU 101, data input from each sensor, and the like. The backup RAM 104 is a non-volatile memory that stores data to be saved when the engine 1 is stopped. is there. The ROM 102, CPU 101, RAM 103, and backup RAM 104 are connected to each other via a bus 107, and are connected to an input interface 105 and an output interface 106.

Connected to the input interface 105 are various sensors such as a water temperature sensor 51, an accelerator position sensor 52 for detecting a depression amount (accelerator opening θ _ACC ) of an accelerator pedal (not shown), a throttle position sensor 53, and a crank position sensor 54. Has been. Thereby, the ECU 100 acquires the engine water temperature Tw, the accelerator opening θ _ACC , the throttle opening θth, and the like, and calculates the engine speed Ne based on the signal from the crank position sensor 54.

  The output interface 106 is connected to an injector 55, an ignition plug igniter 56, a throttle valve throttle motor 57, an OSV 10, and the like. The ECU 100 executes various controls of the engine 1 including fuel injection control of the injector 55, ignition timing control of the ignition plug, throttle valve opening control, and the like based on detection signals of various sensors.

Further, the ECU 100 acquires the engine output P based on the accelerator opening θ _ACC and the engine speed Ne, determines the operation mode based on the acquired engine output P and the engine water temperature Tw, and according to the operation mode. It is configured to control the OSV 10. The operation mode of the present embodiment includes a first operation mode, a second operation mode, and a third operation mode. The first operation mode is, for example, a mode at the time of start-up or city driving (low load), and is a mode when the engine water temperature Tw is lower than a second predetermined temperature T2 (for example, 60 ° C.). The second operation mode is, for example, a mode at a medium load, and is a mode when the engine water temperature Tw is equal to or higher than the second predetermined temperature T2 and the engine output P is smaller than the predetermined output Pp. The third operation mode is, for example, a mode when the load is high, and is a mode when the engine water temperature Tw is equal to or higher than the second predetermined temperature T2 and the engine output P is equal to or higher than the predetermined output Pp.

-OSV configuration and oil supply status in each operation mode-
Next, the configuration of the OSV (solenoid valve) 10 and the oil supply state in each operation mode will be described with reference to FIGS. 3 is a schematic diagram showing the state of the OSV 10 in the first operation mode, FIG. 4 is a schematic diagram showing the state of the OSV 10 in the second operation mode, and FIG. 5 is a state of the OSV 10 in the third operation mode. FIG.

  As shown in FIGS. 3 to 5, the OSV 10 includes a main body portion 20, a cylindrical spool valve 15 having a first valve body 15 a and a second valve body 15 b, a solenoid coil 16, a return spring 17, and a high pressure pressure. An adjustment valve 18 and a low-pressure adjustment valve 19 are provided. The body 20 has a circular valve passage 21 into which the return spring 17 is inserted and the spool valve 15 is inserted, a first oil supply path 22 connected to the second oil supply pipe 12, and an oil return pipe 14. An oil return path 26, first and second branch paths 23 and 24, and a second oil supply path 25 are formed. The first and second branch passages 23 and 24 connect the first oil supply passage 22 and the oil return passage 26 via the valve passage 21, respectively. The second oil supply path 25 connects the first oil supply path 22 and the third oil supply pipe 13 via the valve path 21.

  The return spring 17 is arranged at the end of one side (the side close to the first branch path 23) of the valve passage 21 and biases the spool valve 15 to the other side (the side close to the second branch path 24). . The solenoid coil 16 is disposed in the vicinity of the other end of the valve passage 21, and generates an electromagnetic force when a voltage is applied, thereby causing the spool valve 15 to move to one side against the urging force of the return spring 17. Move. When the first voltage V1 is applied to the solenoid coil 16, the first valve body 15a opens the second branch path 24 as shown in FIG. 3, while the solenoid valve 16 has a second voltage lower than the first voltage V1. In a state where the two voltages V2 are applied or in a state where the voltage is off, the second branch path 24 is closed as shown in FIGS. When the first or second voltage V1, V2 is applied to the solenoid coil 16, the second valve body 15b closes the second oil supply path 25 as shown in FIGS. 3 and 4, while the solenoid coil 16 When no voltage is applied to the second oil supply path 25, the second oil supply path 25 is opened as shown in FIG. The high pressure regulating valve 18 is arranged in the first branch passage 23 and is configured to open when the hydraulic pressure in the first oil supply passage 22 becomes equal to or higher than the first pressure (high pressure, for example, 250 kPa). The low pressure control valve 19 is disposed in the second branch passage 24 and opens when the oil pressure in the first oil supply passage 22 becomes a second pressure (low pressure, for example, 100 kPa) that is lower than the first pressure. It is configured.

  The ECU 100 applies the first voltage V1 to the solenoid coil 16 in the first operation mode. As a result, as shown in FIG. 3, the first valve body 15a is positioned between the first branch path 23 and the second branch path 24, and the second branch path 24 is opened, while the second valve body 15b. Is located at the supply stop position, and the second oil supply path 25 is closed. Thus, since the second oil supply path 25 is closed, no oil is supplied to the oil jet 7. In addition, since the first branch passage 23 provided with the high pressure control valve 18 and the second branch passage 24 provided with the low pressure control valve 19 are both opened, the first oil supply passage 22 is opened. When the internal hydraulic pressure becomes equal to or higher than the second pressure, the low pressure control valve 19 opens. For this reason, the pressure of the oil supplied to the main gallery 5 is set to the second pressure (low pressure).

  Further, the ECU 100 applies the second voltage V2 (<first voltage V1) to the solenoid coil 16 in the second operation mode. As a result, as shown in FIG. 4, the second branch passage 24 is closed by the first valve body 15a, the second valve body 15b is positioned at the supply stop position, and the second oil supply passage 25 is closed. . That is, no oil is supplied to the oil jet 7. In addition, the first branch passage 23 provided with the high pressure control valve 18 is opened, but the second branch passage 24 provided with the low pressure control valve 19 is closed. The high pressure control valve 18 will not open unless the hydraulic pressure in 22 becomes equal to or higher than the first pressure (> second pressure). For this reason, the pressure of the oil supplied to the main gallery 5 is set to the first pressure (high pressure).

  Further, the ECU 100 turns off the voltage applied to the solenoid coil 16 in the third operation mode. As a result, only the urging force of the return spring 17 acts on the spool valve 15, and as shown in FIG. 5, the second branch body 24 is closed by the first valve body 15a and the second valve body. 15b is located at the supply position, and the second oil supply path 25 is opened. That is, oil is supplied to the oil jet 7. Further, similarly to the second operation mode, the pressure of the oil supplied to the main gallery 5 is set to the first pressure (high pressure).

  As described above, in the first and second operation modes, for example, the warm-up performance of the piston 3 is improved by forcibly stopping the injection from the oil jet 7 in a state where the temperature of the piston 3 immediately after the start is low. The following advantages can be obtained. That is, when the fuel injected from the injector 55 is cold or the like is not sufficiently atomized, the oil dilution caused by the mixture of the fuel adhering to the inner peripheral surface of the cylinder and the oil is improved by improving the warm-up property. Can be reduced. Further, by improving the warm-up property, it is possible to suppress incomplete combustion during cold and the like, and reduce particulate matter (PM) containing soot as a main component. Furthermore, energy efficiency can be improved by improving warm-up performance in the cold state, fuel efficiency can be improved, and the load on the oil pump 9 can be reduced by forcibly stopping the injection from the oil jet 7 in the warm state. , Fuel economy can be improved. Further, by stopping oil injection and improving warm-up performance both in the cold time and in the warm time, the generation of deposits can be suppressed and the occurrence of abnormal combustion can be suppressed.

-OSV overheat suppression control-
As described above, in the present embodiment, by using the OSV 10 to forcibly stop the injection from the oil jet 7, it is possible to reduce oil dilution, reduce PM, improve fuel consumption, and suppress abnormal combustion when cold. Therefore, it is possible to improve fuel consumption and suppress abnormal combustion during warm weather. However, the configuration in which oil is supplied to the oil jet 7 via the OSV 10 having the solenoid coil 16 has the following problems.

  That is, in recent years, the exhaust temperature tends to rise to cope with the downsizing of the engine and the tightening of exhaust regulations, and the ambient temperature in the engine compartment tends to rise accordingly. Thus, when the atmospheric temperature in the engine compartment increases, the temperature of the OSV 10 may rise due to heat reception. If the OSV 10 is overheated, the life of the solenoid coil 16 inside the OSV 10 is remarkably reduced, and the life of the OSV 10 may be reduced.

  Therefore, in the present embodiment, the ECU 100 is configured to acquire a parameter related to the internal temperature Tv of the OSV 10 and prohibit the control of the OSV 10 when the parameter is equal to or greater than a threshold value. Specifically, the ECU 100 acquires the engine water temperature Tw detected by the water temperature sensor 51 as a parameter related to the internal temperature Tv of the OSV 10, and the engine water temperature Tw is equal to or higher than a first predetermined temperature (threshold) T1 (> T2). In this case, the control of the OSV 10 is prohibited and the voltage applied to the solenoid coil 16 is turned off. The “first predetermined temperature T1” is set lower than a temperature obtained by subtracting the temperature due to self-heating of the solenoid coil 16 generated by applying a voltage from the heat resistant limit temperature Tb (for example, 120 ° C.) of the OSV 10. Temperature (for example, 90 ° C.).

  According to this configuration, when the engine water temperature Tw is equal to or higher than the first predetermined temperature T1, the voltage applied to the solenoid coil 16 is turned off (= 0), so that the same oil supply state as in the third operation mode is obtained. . As a result, only the urging force of the return spring 17 acts on the spool valve 15 and the second oil supply path 25 is opened, so that the self-heating of the solenoid coil 16 is suppressed while the piston 3 is cooled. be able to. Here, when the engine water temperature Tw is a high temperature equal to or higher than the first predetermined temperature T1, the engine water temperature Tw and the ambient temperature in the engine compartment have a correlation. Thus, the internal temperature Tv of the OSV 10 depends on the temperature due to the self-heating of the solenoid coil 16 and, for example, the ambient temperature in the engine compartment. An increase in temperature Tv can be suppressed. Therefore, according to the present embodiment, it is possible to suppress the internal temperature Tv of the OSV 10 from exceeding the heat resistance limit temperature Tb, and it is possible to suppress a decrease in the life of the OSV 10 due to overheating.

-OSV overheat suppression control routine-
Next, the procedure of OSV overheat suppression control in this embodiment will be described with reference to the flowchart of FIG.

First, in step S1, the ECU 100 acquires the engine water temperature Tw detected by the water temperature sensor 51 and the accelerator opening degree θ _ACC detected by the accelerator position sensor 52, and based on the signal from the crank position sensor 54. The engine speed Ne is calculated.

  In the next step S2, the ECU 100 determines whether or not the engine water temperature Tw acquired in step S1 is lower than the first predetermined temperature T1. If the determination in step S2 is yes, the process proceeds to step S3.

  In the next step S3, the ECU 100 determines whether or not the engine water temperature Tw acquired in step S1 is lower than a second predetermined temperature T2. If the determination in step S3 is YES, the process proceeds to step S4, and the ECU 100 executes control of the OSV 10 in the first operation mode. Specifically, the ECU 100 applies the first voltage V1 to the solenoid coil 16 to stop the supply of oil to the oil jet 7 and to set the pressure of the oil supplied to the main gallery 5 to the second pressure ( Set to low pressure, then return. On the other hand, if the determination in step S2 is NO, that is, if the engine water temperature Tw is equal to or higher than the second predetermined temperature T2 and lower than the first predetermined temperature T1, the process proceeds to step S5.

In next step S5, the ECU 100 uses the map stored in the ROM 102 to determine whether or not the engine output P acquired based on the accelerator opening θ _ACC and the engine speed Ne is less than a predetermined output Pp. If the determination in step S5 is YES, the process proceeds to step S6, and the ECU 100 executes control of the OSV 10 in the second operation mode. Specifically, the ECU 100 applies the second voltage V2 (<V1) to the solenoid coil 16 to stop the supply of oil to the oil jet 7 and to reduce the pressure of the oil supplied to the main gallery 5. Set to the second pressure (high pressure), then return.

  On the other hand, when the determination in step S5 is NO, the process proceeds to step S7, and the ECU 100 executes control of the OSV 10 in the third operation mode. Specifically, the ECU 100 turns off the voltage applied to the solenoid coil 16 to supply oil to the oil jet 7 and to change the pressure of the oil supplied to the main gallery 5 to the second pressure (high pressure). Set and then return.

  On the other hand, if the determination in step S2 is NO, the process proceeds to step S8, where the ECU 100 prohibits control of the OSV 10 and then returns. As a result, the voltage applied to the solenoid coil 16 is turned off, whereby oil is supplied to the oil jet 7 and the pressure of the oil supplied to the main gallery 5 becomes the second pressure (high pressure).

-Specific OSV overheat suppression control-
Next, specific overheat suppression control of the OSV 10 will be described using the timing chart shown in FIG. In FIG. 7, the solid line indicates the engine water temperature Tw, and the broken line indicates the internal temperature Tv of the OSV 10 (atmosphere temperature in the engine compartment + self-heating of the solenoid coil 16).

First, when the engine 1 is started at time t ₀ , the engine water temperature Tw is lower than the second predetermined temperature T2, so the ECU 100 applies the first voltage V1 to the solenoid coil 16 as shown in the lower part of FIG. Then, the engine coolant temperature Tw rises with time, the engine coolant temperature Tw at time t ₁ is the second predetermined temperature or higher T2, ECU 100 applies a second voltage V2 to the solenoid coil 16.

Even after time t ₁ , the engine water temperature Tw rises as time passes. However, when the accelerator pedal is suddenly depressed at time t ₂ and the engine output P becomes equal to or higher than the predetermined output Pp, the ECU 100 applies the voltage applied to the solenoid coil 16. When the engine output P returns to less than the predetermined output Pp at time t ₃ , the ECU 100 applies the second voltage V2 to the solenoid coil 16 again. At this time, since the voltage was not applied to the solenoid coil 16 from time t ₂ to time t ₃ , the internal temperature Tv of the OSV 10 decreases by the amount of self-heating of the solenoid coil 16 (part A in FIG. 7). reference).

Then, when the engine coolant temperature Tw at time t ₄ becomes the first predetermined temperature or higher T1, ECU 100 may prohibit the control of OSV10, As a result, the voltage applied to the solenoid coil 16 becomes zero. As a result, the increase in the internal temperature Tv of the OSV 10 can be suppressed by the amount of the temperature due to the self-heating of the solenoid coil 16. Therefore, as shown in FIG. 7, the internal temperature Tv of the OSV 10 converges to a temperature lower than the heat-resistant limit temperature Tb, although the engine water temperature Tw continues to increase thereafter. Therefore, according to the overheat suppression control of the present embodiment, it is possible to suppress the internal temperature Tv of the OSV 10 from exceeding the heat resistance limit temperature Tb, and to suppress a decrease in the life of the OSV 10 due to overheating.

(Other embodiments)
The present invention is not limited to the embodiments, and can be implemented in various other forms without departing from the spirit or main features thereof.

  In the above embodiment, the engine water temperature Tw is used as a parameter related to the internal temperature Tv of the OSV 10. However, the present invention is not limited to this. For example, when an oil temperature sensor is provided, the parameter related to the internal temperature Tv of the OSV 10 As an alternative, the oil temperature may be used.

  Moreover, although the case where this invention was applied to the direct-injection gasoline engine 1 was demonstrated in the said embodiment, it is not restricted to this, For example, the dual provided with the port injection-type gasoline engine and the port injector and the in-cylinder injector The present invention may be applied to an engine that employs an injector system or a diesel engine.

In the above embodiment, the accelerator opening θ _ACC is used as a parameter for acquiring the engine output P. However, the present invention is not limited to this, and for example, the throttle opening θth or the intake air amount may be used.

  As described above, the above-described embodiment is merely an example in all respects and should not be interpreted in a limited manner. Further, all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

  According to the present invention, since it is possible to suppress a decrease in the life of the solenoid valve due to overheating, it is extremely useful when applied to a control device for an internal combustion engine including an electromagnetic valve that switches between supply and stop of oil supply to an oil jet. is there.

1 engine (internal combustion engine)
3 Piston 7 Oil Jet 10 OSV (Solenoid Valve)
100 ECU (control device)

Claims (1)

An internal combustion engine control device comprising: an oil jet that injects oil toward a piston of the internal combustion engine; and an electromagnetic valve that switches between supply and stop of oil supply to the oil jet,
The solenoid valve has a solenoid coil and a return spring. When the voltage applied to the solenoid coil is turned on, the supply of oil to the oil jet is stopped, while the solenoid valve is applied to the solenoid coil. When the voltage is turned off, the oil is supplied to the oil jet by the urging force of the return spring.
An internal combustion engine that obtains a parameter related to the temperature of the solenoid valve and, when the parameter is equal to or greater than a threshold value, prohibits the control of the solenoid valve and turns off the voltage applied to the solenoid coil. Control device.

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