JP2013007338A - Cooling water circulating device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling water circulating device that can effectively cool an exhaust system at a high-temperature without increasing the size and weight of an internal combustion engine in a cooling water circuit that can cool an intake system and the exhaust system.SOLUTION: In a structure where an intercooler 18 and a water-cooled adaptor 20 are arranged in the high-temperature of the exhaust system in parallel therewith, an electromagnetic switch valve 54 is closed to reduce (actually interrupt) the flow rate of the cooled water with respect to the intercooler 18. As a result, the cooled water is supplied to only a cooled water passage 20a of the water-cooled adaptor 20. Accordingly, even if the flow rate of the cooled water that is pumped from a sub-water pump 50 is equal, the exhaust system which is especially required to be cooled in the high-temperature, can be intensively cooled.

Description

  The present invention relates to an apparatus for circulating cooling water in a cooling water circuit to cool an internal combustion engine.

Techniques have been proposed for solving the inconvenience caused by simultaneously stopping the circulation of cooling water when the internal combustion engine is stopped (see, for example, Patent Documents 1 to 5).
In Patent Document 1, a turbine bearing of a turbocharger that is heated by exhaust heat during operation of the internal combustion engine is cooled by branching cooling water that cools the internal combustion engine body. The cooling of the intercooler for cooling the intake air is performed by forming a separate cooling water circuit having a dedicated radiator and a dedicated electric pump. And since the circulation of the cooling water on the internal combustion engine main body side stops immediately after the internal combustion engine stops, the turbine bearing of the turbocharger is connected to the intercooler by driving the dedicated electric pump to the cooling water of the separate system by switching the switching valve. Are supplied in parallel for cooling.

  In Patent Document 2, a cooling water circuit of a different system from the internal combustion engine main body side is provided. This cooling water circuit is composed of an electric feed pump, a turbocharger bearing housing, a sub-radiator, a sub-tank, and an intercooler connected in series. There is a description that the cooling water circulation can be continued for a certain time after the internal combustion engine is stopped.

  In Patent Document 3, a cooling water circuit of a different system from the internal combustion engine main body side is provided. This cooling water circuit is configured by connecting an internal combustion engine drive or electric feed pump, a flow path switching valve, a radiator, an intercooler, and a heater core in series. This cooling water circuit is a function when the internal combustion engine is driven, and there is no description after the internal combustion engine is stopped. This is because the flow path switching valve bypasses the cooling water so that it does not pass through the radiator during heating.

  In Patent Document 4, high-temperature cooling water flowing through the internal combustion engine body is introduced into the intercooler when the DPF is regenerated, and low-temperature cooling water is introduced into the intercooler from another cooling water circuit by switching the valve during non-regeneration. .

  In Patent Document 5, an exhaust cooling adapter that cools exhaust gas discharged from an exhaust port on the internal combustion engine body side and sends it to the exhaust manifold side, and a cooling water circuit in which cooling water on the internal combustion engine body side is introduced, and a separate system A cooling water circuit into which cooling water from the cooling water circuit is introduced is provided. As a result, exhaust cooling is performed in two stages during operation of the internal combustion engine to prevent insufficient cooling.

Japanese Utility Model Publication No. Hei 4-21724 (pages 6-9, FIG. 1) Japanese Utility Model Publication No. 59-81739 (page 5-8, FIG. 1) JP 2010-115993 A (pages 8-9, FIG. 1) JP 2007-255262 A (page 4, FIGS. 1 and 3) Japanese Utility Model Publication No. 64-15718 (7th and 8th pages, FIGS. 1 and 2)

  In Patent Document 1, cooling water is introduced into a turbine bearing from a cooling water circuit on the main body side of the internal combustion engine as exhaust system cooling during operation of the internal combustion engine. For this reason, high-temperature cooling water is supplied to the exhaust system during high-load operation of the internal combustion engine or when the engine temperature is high. Therefore, the cooling performance in the exhaust system is reduced during operation of the internal combustion engine. In Patent Document 1, when the internal combustion engine is stopped, cooling water is introduced into the turbine bearing from a separate cooling water circuit on the intercooler side, but even if this is applied during operation of the internal combustion engine, supply in parallel with the intercooler is performed. Therefore, it is difficult to introduce a sufficient amount of cooling water. In order to introduce a large amount of cooling water into the turbine bearing, a large water pump is required, which increases the size and weight of the internal combustion engine.

  In Patent Document 2, since the bearing housing of the turbocharger and the intercooler are arranged in series, a sufficient amount of cooling water can be supplied to the bearing housing of the turbocharger that is an exhaust system by an electric feed pump. However, since the intercooler is cooled at the same time, the total amount of heat received is large even if the amount of cooling water is greater than that of Patent Document 1, so that both the exhaust system and the intake system are sufficiently cooled during high-load operation of the internal combustion engine or when the engine is hot Difficult to do. In this case as well, a large water pump is required for sufficient cooling, leading to an increase in size and weight of the internal combustion engine.

In Patent Document 3, the heating effect in the heater core is enhanced, and is not related to the cooling of the exhaust system.
In Patent Document 4, the temperature rise of the exhaust for regeneration of the DPF is irrelevant to the cooling of the exhaust system.

  In Patent Document 5, two-stage cooling is used, but a separate cooling water circuit is exclusively used for exhaust system cooling and is not used for an intercooler. For this reason, it is necessary to provide a separate cooling water circuit for cooling the intercooler, which may increase the size and weight of the internal combustion engine.

  INDUSTRIAL APPLICABILITY The present invention is effective in a cooling water circuit that can cool both an intake system and an exhaust system even when the operating state of the internal combustion engine causes a high temperature of the exhaust system without increasing the size and weight of the internal combustion engine. It aims at realization of the internal-combustion-engine cooling water circulation device which can cool an exhaust system in general.

In the following, means for achieving the above-mentioned purpose, and its operation and effect are described.
The internal combustion engine cooling water circulation device according to claim 1 is an intake system cooling water flow path for cooling an intake system of the internal combustion engine, an exhaust system cooling water flow path for cooling the exhaust system of the internal combustion engine, and cooling cooled by a cooling unit. A cooling water supply unit that supplies water in parallel to the intake system cooling water channel and the exhaust system cooling water channel, and from the cooling water supply unit to the intake system cooling water channel and the exhaust system cooling water channel A cooling water flow rate distribution adjusting unit that adjusts the ratio of the cooling water flow rate, and a cooling water flow rate distribution adjusting unit that adjusts the cooling water flow rate distribution adjusting unit in a state in which the operating state of the internal combustion engine causes a high temperature of the exhaust system, Intake system cooling water flow rate reduction means for reducing the ratio of the water flow rate is provided.

  In a configuration in which the cooling water supply unit supplies cooling water in parallel to the intake system cooling water flow path and the exhaust system cooling water flow path, when the internal combustion engine operating state causes a high temperature of the exhaust system, the intake system cooling The water flow rate reducing means reduces the ratio of the cooling water flow rate of the intake system cooling water flow path by adjusting the cooling water flow rate distribution adjusting unit.

  By reducing the water flow rate ratio of the intake system cooling water flow path, the water flow rate ratio with respect to the exhaust system cooling water flow path arranged in parallel with the intake system cooling water flow path naturally increases. Therefore, even if the cooling water amount is the same as a whole, the exhaust system can be intensively cooled in a state where the operating state of the internal combustion engine causes the exhaust system to become hot.

  As a result, in the cooling water circuit that can cool both the intake system and the exhaust system, it is effective even if the operating state of the internal combustion engine causes a high temperature of the exhaust system without increasing the size and weight of the internal combustion engine. The exhaust system can be cooled.

  In the internal combustion engine cooling water circulation device according to claim 2, in the internal combustion engine cooling water circulation device according to claim 1, the state in which the internal combustion engine operating state causes a high temperature in the exhaust system is a high temperature state of the internal combustion engine. It is characterized by that.

  Thus, if the internal combustion engine temperature is high, the exhaust temperature naturally becomes high. Therefore, the intake system cooling water flow rate reducing means reduces the ratio of the cooling water flow rate of the intake system cooling water flow path so that the exhaust system cooling water flow rate is reduced. The ratio of the cooling water in the road is increased, which makes it possible to cool the exhaust system intensively.

  According to a third aspect of the present invention, there is provided an internal combustion engine cooling water circulating apparatus according to the first aspect, wherein the internal combustion engine operating state causes a high temperature of the exhaust system when the internal combustion engine is in a high load state. It is characterized by that.

  Thus, when the internal combustion engine is in a high load state, the exhaust temperature naturally becomes high. Therefore, the intake system cooling water flow rate reducing means reduces the ratio of the cooling water flow rate of the intake system cooling water flow path, so that the exhaust system The ratio of the cooling water in the cooling water flow path is increased, which makes it possible to cool the exhaust system intensively.

  The internal combustion engine cooling water circulation device according to claim 4, wherein the cooling water flow distribution adjusting unit is provided in the intake system cooling water flow path. The on-off valve is provided.

  By providing the on-off valve in this manner, when the on-off valve is opened, the cooling water supply unit can supply cooling water to both the exhaust system cooling water flow path and the intake system cooling water flow path. However, when the on-off valve is closed, the flow of the cooling water is blocked in the intake system cooling water flow path, so that the cooling water cannot be supplied from the cooling water supply unit to the intake system cooling water flow path. Therefore, all the cooling water supplied from the cooling water supply unit is supplied to the exhaust system cooling water flow path. As a result, the exhaust system can be intensively cooled. In addition, when duty control is performed instead of complete closing of the on-off valve, the cooling water flow rate ratio in the intake system cooling water flow path can be reduced corresponding to the duty. The cooling water flow rate can be increased.

  The internal combustion engine cooling water circulation device according to any one of claims 1 to 4, wherein the internal combustion engine includes a turbocharger, and the intake system cooling water flow path is an intercooler. It is the cooling water flow path as.

  Therefore, in the configuration in which the cooling water supply unit supplies cooling water in parallel to the intercooler and the exhaust system cooling water flow path, in the state where the operating state of the internal combustion engine causes the exhaust system to become hot, the intake system cooling water flow rate The reducing means adjusts the cooling water flow rate distribution adjusting unit to reduce the cooling water flow rate ratio on the intercooler side.

  By reducing the cooling water flow rate ratio in the intercooler, the cooling water flow rate ratio with respect to the exhaust system cooling water flow path arranged in parallel with the intercooler naturally increases. In a state where the temperature of the exhaust system is raised, the exhaust system can be intensively cooled.

  The internal combustion engine cooling water circulation device according to claim 6, wherein the exhaust system cooling water flow path is formed in a water-cooled exhaust manifold in the internal combustion engine cooling water circulation device according to any one of claims 1 to 5. It is a water flow path.

  Therefore, in a configuration in which the cooling water supply unit supplies cooling water in parallel to the intake system cooling water flow path and the water cooling type exhaust manifold, when the operating state of the internal combustion engine causes a high temperature of the exhaust system, the intake system cooling The water flow rate reducing means reduces the ratio of the cooling water flow rate of the intake system cooling water flow path by adjusting the cooling water flow rate distribution adjusting unit.

  By reducing the cooling water flow rate ratio of the intake system cooling water flow path, the cooling water flow rate ratio for the water-cooled exhaust manifold arranged in parallel with the intake system cooling water flow path is naturally increased. Therefore, even if the cooling water amount is the same as a whole, the exhaust system can be intensively cooled in a state where the operating state of the internal combustion engine causes a high temperature of the exhaust system.

  The internal combustion engine cooling water circulation device according to claim 7, wherein the exhaust system cooling water flow path is formed between a cylinder head and an exhaust manifold of the internal combustion engine. It is the cooling water flow path formed in the water cooling adapter arrange | positioned between.

  Therefore, in a configuration in which the cooling water supply unit supplies cooling water in parallel to the intake system cooling water flow path and the water cooling adapter, the intake system cooling water flow rate in a state where the operating state of the internal combustion engine causes a high temperature of the exhaust system The reduction means adjusts the cooling water flow rate distribution adjusting unit to reduce the ratio of the cooling water flow rate of the intake system cooling water flow path.

  By reducing the cooling water flow rate ratio in the intake system cooling water flow path, the cooling water flow rate ratio for the water cooling adapter arranged in parallel with the intake system cooling water flow path is naturally increased. Therefore, even if the cooling water amount is the same as a whole, the exhaust system can be intensively cooled in a state where the operating state of the internal combustion engine causes a high temperature of the exhaust system.

  The internal combustion engine cooling water circulation device according to claim 8, wherein the internal combustion engine is separately cooled for the main body for cooling the internal combustion engine itself. A cooling water circuit comprising a water flow path, a main body cooling section, and a main body cooling water supply section is provided, and the main body cooling water supply section supplies cooling water cooled by the main body cooling section to the main body cooling water flow path. It is characterized by being.

  As described above, the cooling water circuit having the intake system cooling water flow path and the exhaust system cooling water flow path is provided separately from the internal combustion engine body side, so that the intake system cooling water flow path and the exhaust system cooling water flow path are provided. Since the cooling water on the internal combustion engine main body side does not flow, the cooling effect can be enhanced.

  In the internal combustion engine cooling water circulation device according to claim 9, in the internal combustion engine cooling water circulation device according to any one of claims 1 to 8, the cooling water supply unit includes an electric water pump, and after the internal combustion engine is stopped. And a cooling water supply means after stopping the internal combustion engine for driving the electric water pump and supplying the cooling water for a predetermined period.

  Thus, since the cooling water supply unit can supply the cooling water by the electric water pump, the cooling water supply unit can execute the cooling water supply from the cooling water supply unit for a predetermined period after the internal combustion engine is stopped after the internal combustion engine is stopped.

  As a result, boiling of the cooling water in the exhaust system cooling water flow path during dead soak can be prevented, and problems such as catalyst deterioration due to overheating in the exhaust system can be prevented.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration explanatory diagram of an internal combustion engine and a cooling water circulation device of a first embodiment. The flowchart of the sub cooling water system | strain control process of Embodiment 1. FIG. The flowchart of the sub cooling water system | strain control process of Embodiment 2. FIG. FIG. 6 is a configuration explanatory diagram of an internal combustion engine and a cooling water circulation device of a third embodiment. Structure explanatory drawing of the internal combustion engine of other embodiment and its cooling water circulation apparatus. Structure explanatory drawing of the internal combustion engine of other embodiment and its cooling water circulation apparatus. Structure explanatory drawing of the internal combustion engine of other embodiment and its cooling water circulation apparatus.

[Embodiment 1]
<Structure> FIG. 1 shows an internal combustion engine to which the above-described invention is applied and its cooling water circulation device. This internal combustion engine is a vehicle-mounted in-line four-cylinder gasoline engine, and four cylinders 4 are arranged in a line in an internal combustion engine body 2 having a cylinder head, a cylinder block, a piston, and the like. The internal combustion engine is provided with an intake passage 6 for supplying intake air and an exhaust passage 8 for discharging exhaust gas.

  The intake passage 6 includes an intake manifold 16 that also serves as an air cleaner 10, a compressor 12a of a turbocharger 12, a throttle valve 14, and a surge tank from the upstream side. With this configuration, intake air is distributed and supplied to each cylinder 4 via an intake port formed in the cylinder bed 2a. An intercooler 18 that cools intake air with cooling water is provided integrally with the surge tank portion 16a of the intake manifold 16. As for the fuel, fuel is injected into the intake air flow by providing a fuel injection valve at a branch portion of the intake manifold 16 or at each intake port. The fuel injection valve may be arranged to inject directly into the cylinder 4.

  The exhaust passage 8 includes, from upstream, a water-cooling adapter 20 for exhaust cooling connected to a portion where four exhaust ports are opened in the cylinder bed 2a, an exhaust manifold 22 connected to the water-cooling adapter 20, and a turbine 12b of the turbocharger 12. And an exhaust purification catalytic converter 24. A muffler is further provided downstream of this.

  Here, in the water cooling adapter 20, four exhaust passages are formed corresponding to the four exhaust ports, and two cooling water passages 20a and 20b are provided around the exhaust passage. Thus, the exhaust immediately after being discharged from the exhaust port is cooled by the cooling water flowing in one or both of the two cooling water flow paths 20a and 20b, and can be discharged to the exhaust manifold 22 side.

A cooling water circulation device is formed for such an internal combustion engine, but the cooling system is divided into two systems.
The main cooling water system is a cooling water circuit using a cooling water flow generated by a water pump 30 driven by an internal combustion engine. In the cooling water circuit, there is a cooling water circulation path including a water pump 30, a water jacket 32 in the internal combustion engine body 2, a thermostat valve 34, and a radiator 36 in the order of the flow direction of the cooling water flow. Further, in this cooling water circulation path, one cooling water flow path 20 b in the water cooling adapter 20 exists in parallel with the water jacket 32, and further, a bypass path 38 connecting the upstream side of the thermostat valve 34 and the downstream side of the radiator 36. Is provided.

  FIG. 1 shows a state where the thermostat valve 34 is opened after warming up. However, when the thermostat valve 34 is cold, the thermostat valve 34 is in a closed state so that the cooling water flows to the bypass path 38 side and does not pass through the radiator 36.

  The sub cooling water system is a cooling water circuit using a cooling water flow generated by the sub water pump 50 driven by the electric motor 50a. In this cooling water circuit, there is a cooling water circulation path composed of the sub-water pump 50, the intercooler 18, and the intercooler radiator 52 in the order of the flow direction of the cooling water flow. Furthermore, another cooling water flow path 20 a in the water cooling adapter 20 exists in parallel with the intercooler 18 in this cooling water circulation path.

  A normally-open electromagnetic on-off valve 54 is provided in the inlet-side cooling water flow path of the intercooler 18, and if it is open, the cooling water from the sub-water pump 50 can flow into the intercooler 18 together with the water-cooling adapter 20 side. it can. However, in the closed state, the cooling water does not flow through the intercooler 18, and all the cooling water supplied from the sub-water pump 50 flows into the cooling water flow path 20 a in the water cooling adapter 20.

  The electric motor 50 a that drives the sub-water pump 50 and the electromagnetic on-off valve 54 are controlled by the control unit 56. The control unit 56 is configured as an electronic control circuit centered on a microcomputer, and controls each part of the internal combustion engine. For example, the opening degree (throttle opening degree) of the throttle valve 14 driven by the electric motor 14a is adjusted according to the operation amount of the accelerator pedal and other factors.

In the present embodiment, the control unit 56 further detects the cooling water temperature THW from the cooling water temperature sensor 58 disposed in the internal combustion engine body 2, and based on the result, the drive state of the electric motor 50a and the open / close state of the electromagnetic on-off valve 54 are detected. Is controlling.
<Operation> The operation of the present embodiment will be described based on the sub cooling water system control process executed by the control unit 56. FIG. 2 shows a flowchart of the sub cooling water system control process. This process is repeatedly executed in a time cycle. The steps in the flowchart corresponding to the individual processing contents are represented by “S˜”.

  When this process is started, it is first determined whether or not the drive condition for the sub-water pump 50 is satisfied (S102). The driving conditions of the sub-water pump 50 are (A) a state after warm-up when the internal combustion engine is operating, and (B) a state within a predetermined period immediately after the stop when the internal combustion engine is stopped. In step S102, it is determined whether any of the condition (A) and the condition (B) is satisfied.

  Here, in the cold state immediately after the internal combustion engine is started, the conditions (A) and (B) are not satisfied (NO in S102), so the electric motor 50a is stopped (S104). . If the electric motor 50a is already in a stopped state, that state is maintained. For this reason, the cooling water is not supplied from the sub-water pump 50 to the intercooler 18 and the water cooling adapter 20. Therefore, warm-up is promoted.

  When the warm-up of the internal combustion engine is completed, the condition (A) is satisfied (YES in S102), so the electric motor 50a is driven (S106). If the electric motor 50a is already in a driving state, that state is maintained. For this reason, the cooling water is supplied from the sub-water pump 50 to the intercooler 18 and the water cooling adapter 20 to cool each part.

  Next, it is determined whether or not the exhaust system is in a high temperature state (S108). Here, for example, the determination is made based on whether or not the coolant temperature THW detected by the coolant temperature sensor 58 is equal to or higher than a reference temperature corresponding to the exhaust system high temperature state. In addition to this, it may be determined by directly detecting the exhaust temperature, or may be determined by calculating the temperature of the exhaust system based on the history of the load of the internal combustion engine.

  When the exhaust system is not in a high temperature state (cooling water temperature THW <reference temperature) (NO in S108), the electromagnetic on-off valve 54 disposed at the inlet of the cooling water flow path of the intercooler 18 is opened (S110). . If the electromagnetic on-off valve 54 is already open, that state is maintained.

  Thereafter, if the internal combustion engine continues to operate (YES in S102) and the exhaust system does not become hot (NO in S108), cooling water is supplied from the sub-water pump 50 to the intercooler 18 and the water cooling adapter 20. The intercooler 18 cools the intake air, and the water cooling adapter 20 cools the exhaust. Then, the cooling water discharged from the intercooler 18 and the water cooling adapter 20 is radiated by the intercooler radiator 52 to lower the temperature, and is sent again from the sub-water pump 50 to the intercooler 18 and the water cooling adapter 20.

  Here, when the exhaust system becomes a high temperature state (cooling water temperature THW ≧ reference temperature) due to a high load state of the internal combustion engine or the like (YES in S108), the electromagnetic on-off valve 54 is closed (S112). If the electromagnetic opening / closing valve 54 is already closed, that state is maintained.

  As a result, the cooling water delivered from the sub-water pump 50 is not distributed to the intercooler 18, and all is supplied to the cooling water flow path 20 a in the water-cooling adapter 20. Therefore, the cooling efficiency in the exhaust system in which cooling is particularly important increases.

  If the exhaust system returns to a state where the temperature is not high (cooling water temperature THW <reference temperature) (NO in S108), the electromagnetic on-off valve 54 returns to the open state (S110). As a result, the cooling water delivered from the sub-water pump 50 is distributed to both the intercooler 18 and the water cooling adapter 20 to return to a state in which both the intake system and the exhaust system are cooled.

  When the internal combustion engine is stopped, the condition (B) is satisfied immediately after the stop (YES in S102), so that the driving state of the sub-water pump 50 by the rotation of the electric motor 50a is continued (S106). If the internal combustion engine exhaust system is not in a high temperature state during this stop (NO in S108), the electromagnetic on-off valve 54 is opened (S110). For this reason, the flow of the cooling water in the intercooler 18 and the water cooling adapter 20 continues. At this time, since the turbocharger 12 is stopped, the cooling of the exhaust system by the water cooling adapter 20 is particularly effectively performed.

Since the condition (B) is not satisfied after the elapse of a predetermined period from the stop of the internal combustion engine and (A) is also not satisfied (NO in S102), the rotation of the electric motor 50a is stopped (S104). As a result, the cooling water from the sub water pump 50 is also stopped, and the cooling by the sub cooling water system is stopped.
<Relationship with Claims> In the configuration described above, the intercooler 18 is in the intake system cooling water flow path, the electric motor 50a and the sub-water pump 50 are in the cooling water supply section, and the cooling water flow path 20a in the water cooling adapter 20 is exhausted. In the system cooling water flow path, the intercooler radiator 52 corresponds to a cooling unit, and the electromagnetic on-off valve 54 corresponds to a cooling water flow rate distribution adjusting unit.

  The cooling water flow path 20b and the water jacket 32 in the water cooling adapter 20 correspond to the main body cooling water flow path, the radiator 36 corresponds to the main body cooling section, and the water pump 30 driven by the internal combustion engine corresponds to the main body cooling water supply section.

The control unit 56 corresponds to intake air cooling water flow rate reducing means and cooling water supply means after stopping the internal combustion engine. In the sub-cooling water system control processing (FIG. 2) executed by the control unit 56, steps S108 and S112 are executed as processing for reducing the intake-system cooling water flow rate, and step S106 is executed when the condition (B) in step S102 is satisfied. Corresponds to processing as cooling water supply means after the internal combustion engine is stopped.
<Effect> (1) The sub-water pump 50 supplies cooling water to the intercooler 18 and the water-cooling adapter 20 in parallel. In such a configuration, when it is determined that the coolant temperature THW reflecting the internal combustion engine temperature is equal to or higher than the reference temperature and the internal combustion engine operating state is a state that causes a high temperature of the exhaust system (YES in S108). The electromagnetic on-off valve 54 is closed (S112). As a result, the ratio of the coolant flow rate to the intercooler 18 is reduced. Actually, in the sub cooling water system, no cooling water is supplied to the intercooler 18 side, and only the cooling water flow path 20a in the water cooling adapter 20 is supplied. This increases the cooling water flow rate in the cooling water flow path 20a in the water cooling adapter 20. Therefore, even if the flow rate of the cooling water delivered from the sub-water pump 50 is the same, particularly in the state where the internal combustion engine operation state causes a high temperature of the exhaust system, it is possible to intensively cool the exhaust system in which cooling is important. it can.

  Thus, in the cooling water circuit of the sub cooling water system in which both the intake system and the exhaust system can be cooled by the intercooler 18 and the water cooling adapter 20, the operating state of the internal combustion engine is exhausted without increasing the size and weight of the internal combustion engine. The exhaust system can be effectively cooled even when the temperature of the system increases.

  (2) The sub cooling water system is formed as a separate system separately from the main cooling water system that cools the internal combustion engine body 2 side. As a result, the cooling water from the main cooling water system that is heated to a higher temperature does not flow into the sub cooling water system, so that the cooling effect of each part by the sub cooling water system can be enhanced.

  (3) The sub-water pump 50 is driven by the electric motor 50a and can supply cooling water even when the internal combustion engine is stopped. Therefore, as described above, the cooling water can be supplied to the intercooler 18 and the water cooling adapter 20 for a predetermined period after the internal combustion engine is stopped by the determination of the condition (B).

As a result, boiling of the cooling water in the water-cooled adapter 20 can be prevented particularly during dead soaking, and problems such as catalyst deterioration due to overheating in the exhaust system can be prevented.
[Embodiment 2]
<Configuration> In the present embodiment, in the configuration shown in FIG. 1, the control unit 56 executes the sub-cooling water system control process shown in FIG. 3 in a time period instead of FIG.
<Operation> The sub-cooling water system control process (FIG. 3) will be described. When this process is started, it is first determined whether or not the driving condition of the sub-water pump 50 is satisfied (S202). The determination in step S202 is the same as step S102 in FIG.

If the drive condition of the sub-water pump 50 is not satisfied (NO in S202), the electric motor 50a is stopped (S204) as in step S104 of FIG.
If the drive condition for the sub-water pump 50 is satisfied (YES in S202), the electric motor 50a is driven as in step S106 of FIG. 2 (S206).

  Next, it is determined whether or not the internal combustion engine is in a high load state (S208). If the internal combustion engine is not at a high load (NO in S208), the electromagnetic on-off valve 54 is opened (S210) as in step S110 of FIG. It should be noted that the state where the internal combustion engine is not heavily loaded also includes when the internal combustion engine is stopped.

  If the load is high (YES in S208), throttle opening reduction processing is executed (S212). The throttle opening reduction process is a process performed to prevent boiling of the cooling water in the water cooling adapter 20, and is a process of reducing the exhaust temperature by reducing the current throttle opening in the throttle valve 14.

Then, the opening degree of the electromagnetic on-off valve 54 is also reduced corresponding to the throttle opening reduction amount (S214). The opening control of the electromagnetic opening / closing valve 54 is executed by duty control.
<Relationship with Claims> In the configuration described above, the contents other than the execution contents of the control unit 56 are as described in the first embodiment. In the sub-cooling water system control processing (FIG. 3) executed by the control unit 56, steps S208 and S214 are processing as the intake-system cooling water flow rate reducing means, and processing that executes step S206 according to the condition (B) in step S202 is internal combustion. This corresponds to processing as cooling water supply means after the engine is stopped.
<Effect> (1) The effect of the first embodiment is produced. In particular, when the internal combustion engine is at a high load, the throttle opening is reduced (S212), and the reduction in the flow rate of the coolant flowing through the intercooler 18 corresponds to the reduction in the intake air amount due to the reduction in the throttle opening (S214). For this reason, the exhaust cooling effect in the water cooling adapter 20 can be enhanced without affecting the cooling performance in the intake system.

[Embodiment 3]
<Structure> In the present embodiment, as shown in FIG. 4, the two cooling water flow paths 120 a and 120 b are formed in the water cooling adapter 120, but the cooling water flow path 120 a of the sub cooling water system is further The exhaust manifold 122 is continuously formed from the exhaust passage 108 and the housing of the turbine 112b. As a result, the exhaust system is formed as a water-cooled exhaust manifold.

And the control part 156 performs the sub cooling water system | strain control process shown in the said FIG. 2 or the said FIG.
<Operation> Even in the configuration in which the cooling water flow path 120a is extended to the housing of the turbine 112b, the subcooling water system control processing (FIG. 2 or FIG. 3) can be applied to the first embodiment or the second embodiment. The operation is as described above.
<Relationship with Claims> As described in the first embodiment or the second embodiment.
<Effect> (1) As described in the first embodiment or the second embodiment, not only the water cooling adapter 120 but also the exhaust manifold 122, the exhaust passage 108, and the housing of the turbine 112b are effectively cooled. be able to.

[Other embodiments]
In FIG. 1, the cooling water flow paths in the water cooling adapter are provided separately for the main cooling water system and the sub cooling water system. However, as shown in FIG. 5, the cooling water flow path 220a has a single cooling water flow path 220a. Alternatively, the main cooling water system and the sub cooling water system may be shared.

  Further, also in FIG. 4, the main cooling water system and the sub-cooling are formed even when the cooling water flow path 320a is continuously formed from the water cooling adapter 320 to the exhaust manifold 322, the exhaust passage 308 and the housing of the turbine 312b as shown in FIG. It may be shared with the water system.

In FIGS. 1 and 4 to 6, the electromagnetic on-off valve is arranged in the cooling water flow path on the inlet side (upstream side) with respect to the intercooler, but may be arranged on the outlet side (downstream side).
In the sub-cooling water system of each of the above embodiments, an electromagnetic on-off valve is provided in the cooling water flow path on the intercooler side, so that the electromagnetic on-off valve is normally opened to supply cooling water to both the intercooler and the water cooling adapter. When the temperature of the exhaust system is high, the electromagnetic on-off valve is closed or duty control is performed to reduce (including shut off) the coolant flow rate on the intercooler side.

  In addition to this, as shown in FIG. 7, a switching valve 454 is disposed at a branch portion between the intercooler 418 arranged in parallel with the sub-water pump 450 and the cooling water flow path 420 a of the water cooling adapter 420. The control unit 456 may control the switching direction of the valve 454.

  That is, during normal internal combustion engine operation, the cooling water of the main cooling water system is flowing into one cooling water flow path 420b in the water cooling adapter 420, so that the cooling water supply from the sub-water pump 450 is only the intercooler 418. The switching valve 454 is switched as follows. When the exhaust system is heated, in the sub cooling water system, the cooling water from the sub water pump 450 is supplied only to the cooling water flow path 420 a of the water cooling adapter 420. Further, the cooling water from the sub-water pump 450 is supplied only to the cooling water flow path 420a of the water cooling adapter 420 even during the dead soak. Even if it does in this way, the effect as described in the said Embodiment 1 will arise.

  2 ... Internal combustion engine body, 2a ... Cylinder bed, 4 ... Cylinder, 6 ... Intake passage, 8 ... Exhaust passage, 10 ... Air cleaner, 12 ... Turbocharger, 12a ... Compressor, 12b ... Turbine, 14 ... Throttle valve, 14a ... Electric Motor, 16 ... Intake manifold, 16a ... Surge tank, 18 ... Intercooler, 20 ... Water cooling adapter, 20a, 20b ... Cooling water flow path, 22 ... Exhaust manifold, 24 ... Exhaust purification catalytic converter, 30 ... Water pump, 32 DESCRIPTION OF SYMBOLS ... Water jacket, 34 ... Thermostat valve, 36 ... Radiator, 38 ... Bypass path, 50 ... Sub-water pump, 50a ... Electric motor, 52 ... Radiator for intercooler, 54 ... Electromagnetic switching valve, 56 ... Control part, 58 ... Cooling Water temperature sensor 108 ... exhaust passage 112b ... 120, water cooling adapter, 120a, 120b ... cooling water flow path, 122 ... exhaust manifold, 156 ... control unit, 220 ... water cooling adapter, 220a ... cooling water flow path, 308 ... exhaust passage, 312b ... turbine, 320 ... water cooling adapter, 320a ... Cooling water flow path, 322 ... Exhaust manifold, 418 ... Intercooler, 420 ... Water cooling adapter, 420a, 420b ... Cooling water flow path, 450 ... Sub-water pump, 454 ... Switching valve, 456 ... Control part.

Claims (9)

An intake system coolant flow path for cooling the intake system of the internal combustion engine;
An exhaust system cooling water flow path for cooling the exhaust system of the internal combustion engine;
A cooling water supply unit that supplies the cooling water cooled by the cooling unit in parallel to the intake system cooling water channel and the exhaust system cooling water channel;
A cooling water flow rate distribution adjusting unit for adjusting a ratio of a cooling water flow rate from the cooling water supply unit to the intake system cooling water channel and the exhaust system cooling water channel;
An intake system cooling water flow rate reducing means that adjusts the cooling water flow rate distribution adjusting unit to reduce a ratio of the cooling water flow rate of the intake system cooling water flow path when the internal combustion engine operation state causes a high temperature of the exhaust system;
An internal combustion engine cooling water circulation device comprising: 2. The internal combustion engine cooling water circulation device according to claim 1, wherein the internal combustion engine operating state causes a high temperature of the exhaust system when the internal combustion engine temperature is a high temperature state. 2. The internal combustion engine cooling water circulation device according to claim 1, wherein the internal combustion engine operating state causes a high temperature of the exhaust system when the internal combustion engine is in a high load state. The internal combustion engine cooling water circulation device according to any one of claims 1 to 3, wherein the cooling water flow distribution adjusting unit is an on-off valve provided in the intake system cooling water flow path. Cooling water circulation device. 5. The internal combustion engine cooling water circulation device according to claim 1, wherein the internal combustion engine includes a turbocharger, and the intake system cooling water flow path is a cooling water flow path as an intercooler. Engine cooling water circulation device. 6. The internal combustion engine cooling water circulation device according to claim 1, wherein the exhaust system cooling water flow path is a cooling water flow path formed in a water-cooled exhaust manifold. apparatus. 6. The internal combustion engine cooling water circulation device according to any one of claims 1 to 5, wherein the exhaust system cooling water flow path is formed in a water cooling adapter disposed between a cylinder head of the internal combustion engine and an exhaust manifold. An internal combustion engine cooling water circulation device characterized by being a water flow path. The internal combustion engine cooling water circulation device according to any one of claims 1 to 7, wherein the internal combustion engine separately includes a main body cooling water flow path, a main body cooling unit, and a main body cooling water supply for cooling the internal combustion engine itself. An internal combustion engine cooling water circulation device comprising a cooling water circuit comprising a main part, wherein the main body cooling water supply part supplies the cooling water cooled by the main body cooling part to the main body cooling water flow path. In the internal combustion engine cooling water circulation device according to any one of claims 1 to 8, the cooling water supply unit includes an electric water pump,
An internal-combustion-engine cooling water circulation device comprising: an internal-combustion-engine post-stop cooling water supply unit that drives the electric water pump to supply cooling water for a predetermined period after the internal combustion engine is stopped.

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