WO2015102037A1

WO2015102037A1 - Intake air cooling device

Info

Publication number: WO2015102037A1
Application number: PCT/JP2014/005752
Authority: WO
Inventors: 太一浅野; 雄史川口
Original assignee: 株式会社デンソー
Priority date: 2014-01-06
Filing date: 2014-11-17
Publication date: 2015-07-09
Also published as: CN105874182A; JP6201886B2; DE112014006108T5; CN105874182B; DE112014006108B4; JP2015145667A

Abstract

This intake air cooling device is equipped with: a first radiator (13) that causes heat to be exchanged between a cooling fluid flowing out from an engine (11) and the outside air; a second radiator (14) that causes heat to be exchanged between the cooling fluid that has been cooled by the first radiator (13) and the outside air; a first intercooler (15) that causes heat to be exchanged between the cooling fluid that has been cooled by the second radiator (14) and intake air to the engine (11), thereby cooling the intake air; a second intercooler (16) that causes heat to be exchanged between the cooling fluid flowing out from the engine (11) and the intake air to the engine (11), thereby cooling the intake air; a branching section (23) that causes the flow of the cooling fluid flowing out from the engine (11) to split into a first radiator-side flow (FR) toward the first radiator (13) and a second intercooler-side flow (FI) toward the second intercooler (16); and a switching section (17) that blocks or allows the first radiator-side flow (FR) to circulate.

Description

Intake air cooling system

Cross-reference of related applications

This application includes Japanese Patent Application No. 2014-000101 filed on January 6, 2014, and Japanese Patent Application 2014 filed on May 14, 2014, the disclosures of which are incorporated herein by reference. Based on No. 1000012.

The present disclosure relates to an intake air cooling device that cools intake air of an engine.

Conventionally, Patent Document 1 describes a cooling device including a heat exchanger that cools a heat exchange fluid to two temperature levels. This heat exchanger has one inflow nozzle, two outflow nozzles, and three flow paths. The heat exchange fluid flows from one inflow nozzle. The heat exchange fluid that has passed through only one of the three channels flows out from one outflow nozzle, and the heat medium that has passed through all three channels flows out from the other outflow nozzle.

The heat exchange fluid flowing out from one outflow nozzle is at a higher temperature than the heat exchange fluid flowing out from the other outflow nozzle.

Special Table 2006-523160

In recent years, there are an increasing number of supercharged downsizing vehicles that improve fuel efficiency by adopting turbocharged small displacement engines. In the supercharged downsizing vehicle, it is preferable that the intercooler that cools the supercharged air is a water-cooled type. This is because when the intercooler is water-cooled, the capacity of the intake system can be reduced as compared with the case where the intercooler is air-cooled, so that the engine response can be improved.

The intercooler cools the supercharged air to a temperature about 10 ° C higher than the outside air temperature. Therefore, when adopting a water-cooled intercooler, it is necessary to circulate cooling water having a temperature lower than that of the circulating water (about 80 ° C.) circulating in the existing engine cooling circuit to the water-cooled intercooler.

Therefore, a configuration in which the cooling water circulating in the engine cooling circuit is further cooled and then distributed to the water-cooled intercooler can be considered. Specifically, a configuration in which a part of the cooling water cooled by an existing radiator provided in the engine cooling circuit is further cooled by an intercooler radiator and then distributed to the intercooler can be considered.

According to this configuration, the cooling water can be distributed to the water-cooled intercooler using the existing pump provided in the engine cooling circuit. Therefore, the number of pumps can be reduced as compared with the configuration in which the cooling water circuit for the water-cooled intercooler is provided independently of the engine cooling circuit.

However, according to this configuration, the cooling water of the engine cooling circuit is always cooled by circulating through the radiator for the intercooler, so that the warm-up performance may be impaired. That is, it takes time for the cooling water to warm up to an appropriate temperature (about 80 ° C.) during warm-up immediately after starting the engine, which may deteriorate the fuel consumption of the engine (see FIG. 3 described later). ).

As a countermeasure, it is conceivable to ensure the warm-up performance by preventing the cooling water from the engine cooling circuit from flowing to the intercooler radiator during warm-up. However, according to this measure, there is a possibility that the intake air cannot be cooled when warming up.

In view of the above points, the present disclosure aims to suppress the deterioration of the engine warm-up performance while ensuring the cooling performance of the engine intake air.

The intake air cooling device according to the first aspect of the present disclosure includes a first radiator, a second radiator, a first intake air cooler, a second intake air cooler, a branching unit, and a switching unit. The first radiator cools the cooling fluid by exchanging heat between the cooling fluid flowing out from the engine and the outside air. The second radiator cools the cooling fluid by exchanging heat between the cooling fluid cooled by the first radiator and the outside air. The first intake air cooler cools the intake air by exchanging heat between the cooling fluid cooled by the second radiator and the intake air of the engine. The second intake air cooler cools the intake air by exchanging heat between the cooling fluid that flows by bypassing the first radiator and the second radiator and the intake air of the engine. The branching portion branches the flow of the cooling fluid into a first radiator side flow toward the first radiator and a second intake cooler side flow toward the second intake cooler. The switching unit blocks or distributes the first radiator side flow.

When the switching unit cuts off the flow on the first radiator side, the cooling fluid does not flow through the first radiator and the second radiator. Therefore, it can suppress that heat is dissipated from the cooling fluid to the outside air, and thus it is possible to suppress the engine warm-up performance from being impaired.

Furthermore, even if the switching unit cuts off the first radiator side flow, the cooling fluid of the second intake air cooler side flow flows through the second intake air cooler, so that the intake air of the engine can be cooled.

Therefore, it is possible to prevent the warm-up performance of the engine from being impaired while ensuring the cooling performance of the intake air of the engine.

The intake air cooling device according to the second aspect of the present disclosure includes a first radiator, a second radiator, a first intake air cooler, a second intake air cooler, a branching unit, and a switching unit. The first radiator cools the cooling fluid by exchanging heat between the cooling fluid flowing out from the engine and the outside air. The second radiator cools the cooling fluid by exchanging heat between the cooling fluid cooled by the first radiator and the outside air. The first intake air cooler cools the intake air by exchanging heat between the cooling fluid cooled by the second radiator and the intake air of the engine. The second intake air cooler cools the intake air by exchanging heat between the cooling fluid flowing out from the engine and the intake air of the engine. The branching portion branches the flow of the cooling fluid flowing out from the engine into a first radiator side flow toward the first radiator and a second intake cooler side flow toward the second intake cooler. The switching unit blocks or distributes the first radiator side flow.

According to this, it is possible to achieve the same effects as the effects of the first aspect described above.

It is a whole lineblock diagram of the engine cooling circuit in a 1st embodiment. It is a perspective view of the 1st intercooler in a 1st embodiment. FIG. 3 is a cross-sectional view taken along the line III-III in FIG. It is sectional drawing of the circulation channel on-off valve in 1st Embodiment. In the engine cooling circuit of 1st Embodiment, it is a figure which shows the flow of the cooling water in case the circulation flow path on-off valve is closing. It is a whole block diagram of the engine cooling circuit in 2nd Embodiment. It is a whole block diagram of the engine cooling circuit in 3rd Embodiment. It is a whole block diagram of the engine cooling circuit in 4th Embodiment. In an engine cooling circuit of a 4th embodiment, it is a figure showing a flow of cooling water in case a circulation channel on-off valve is closed.

Hereinafter, embodiments will be described with reference to the drawings. In the following embodiments, the same or equivalent parts are denoted by the same reference numerals in the drawings.
(First embodiment)
FIG. 1 shows an engine cooling circuit 10 constituting the intake air cooling device. The engine cooling circuit 10 is a circuit through which cooling water (cooling fluid) for cooling the engine 11 circulates. The engine 11 is an internal combustion engine that generates driving power for the vehicle.

A cooling water passage through which cooling water flows is formed inside the engine 11. In this embodiment, the cooling water is an ethylene glycol antifreeze (LLC). The intake air (intake air) of the engine 11 is supercharged by a supercharger (not shown).

The engine cooling circuit 10 includes a pump 12, a first radiator 13, a second radiator 14, a first intercooler 15, a second intercooler 16, and a circulation flow path opening / closing valve 17. The pump 12, the engine 11, the circulation channel opening / closing valve 17, and the first radiator 13 are arranged in this order in the circulation channel 18 through which the cooling water circulates.

The pump 12 is a fluid machine that sucks and discharges cooling water. In the present embodiment, the pump 12 is a mechanical pump that is driven by the power output from the engine 11. The pump 12 may be an electric pump driven by an electric motor.

The first radiator 13 is a heat exchanger that cools the cooling water by exchanging heat between the cooling water flowing out from the engine 11 and the outside air. In other words, the first radiator 13 is a radiator that radiates heat of the cooling water to the outside air.

The second radiator 14 and the first intercooler 15 are disposed in the first intake air cooling channel 19. The first intake cooling channel 19 is a channel that branches from the circulation channel 18 and joins the circulation channel 18.

A first branching section 20 where the first intake cooling flow path 19 branches from the circulation flow path 18 and a first merging section 21 where the first intake cooling flow path 19 merges with the circulation flow path 18 include the first radiator 13. The cooling water outlet side of the pump 12 and the cooling water suction side of the pump 12 are provided.

The second radiator 14 is a heat exchanger that cools the cooling water by exchanging heat between the cooling water and the outside air. In other words, the second radiator 14 is a radiator that radiates heat of the cooling water to the outside air.

In the example of FIG. 1, the second radiator 14 is integrated with the first radiator 13, but may be configured separately from the first radiator 13. When the second radiator 14 is integrated with the first radiator 13, the first branch portion 20 may be provided in a cooling water outlet side tank of the first radiator 13.

The first intercooler 15 is an intake air cooler (first intake air cooler) that cools the supercharged intake air by exchanging heat between the supercharged intake air that has been compressed by the supercharger (turbocharger) and becomes high temperature and the cooling water. It is. In order to reduce the capacity of the intake system as much as possible, the first intercooler 15 is disposed adjacent to the engine 11.

The cooling water inlet of the first intercooler 15 is connected to the cooling water outlet of the second radiator 14. The cooling water outlet of the first intercooler 15 is connected to the cooling water inlet of the pump 12.

The second intercooler 16 is disposed in the second intake air cooling flow path 22. The second intake cooling flow path 22 is a flow path that branches from the circulation flow path 18 and merges with the circulation flow path 18.

A second branch portion 23 where the second intake air cooling flow path 22 branches from the circulation flow path 18 is provided on the cooling water outlet side of the engine 11 and on the cooling water inlet side of the first radiator 13. . The second intake cooling flow path 22 joins the first intake cooling flow path 19 at the second merging portion 24, and passes through a part of the first intake cooling flow path 19 at the first merging portion 21. It joins the circulation channel 18.

The second intercooler 16 is an intake air cooler (second intake air cooler) that cools the supercharged intake air by exchanging heat between the supercharged intake air that has been compressed by the supercharger (turbocharger) and becomes high temperature and the cooling water It is. The second intercooler 16 is integrated with the first intercooler 15 in order to minimize the capacity of the intake system. The second intercooler 16 may be configured separately from the first intercooler 15.

The cooling water inlet of the second intercooler 16 is connected to the cooling water discharge port of the pump 12. The coolant outlet of the second intercooler 16 is connected to the coolant inlet of the pump 12.

The second intercooler 16 is located upstream of the first intercooler 15 in the supercharging intake air flow direction. Accordingly, the supercharged intake air flows in the order of the second intercooler 16 and the first intercooler 15.

The circulation channel opening / closing valve 17 is a switching unit that blocks or circulates the coolant flow in the circulation channel 18, and opens and closes the circulation channel 18 according to the temperature Tw (cooling fluid temperature) of the coolant. The circulation flow path opening / closing valve 17 is a mechanical valve that opens and closes a valve body by a mechanical mechanism.

For example, the circulation flow path opening / closing valve 17 is a mechanical thermostat valve. The mechanical thermostat is a cooling water temperature responsive valve configured by a mechanical mechanism that opens and closes a cooling water flow path by displacing a valve body by a thermo wax (temperature sensitive member) whose volume changes with temperature. The circulation channel opening / closing valve 17 may be an electronic control valve.

The circulation channel opening / closing valve 17 is closed when the cooling water temperature Tw is lower than the predetermined temperature Tw1, and is opened when the cooling water temperature Tw is equal to or higher than the predetermined temperature Tw1. In the present embodiment, the predetermined temperature Tw1 is set to 80 ° C. or higher and 90 ° C. or lower.

In the example of FIG. 1, the circulation channel opening / closing valve 17 is located on the cooling water inlet side of the first radiator 13, but may be located on the cooling water outlet side of the first radiator 13. The circulation channel opening / closing valve 17 may be incorporated in the cooling water inlet side tank or the cooling water outlet side tank of the first radiator 13. In the example of FIG. 1, a second branch portion 23 is formed inside the circulation flow path opening / closing valve 17.

Next, the detailed configuration of the first intercooler 15 and the second intercooler 16 will be described with reference to FIGS.

The first intercooler 15 and the second intercooler 16 of the present embodiment are each a plurality of tubes through which cooling water flows, and a collection of cooling water that is arranged on both ends of the plurality of tubes and flows through the tubes. Alternatively, it has a pair of collective distribution tanks 26 that perform distribution. The first intercooler 15 and the second intercooler 16 are configured as so-called tank-and-tube heat exchangers.

As shown in FIG. 3, the first intercooler 15 has a plurality of tubes 15a through which cooling water flows. The tube 15a is a flat tube whose vertical cross-sectional shape in the longitudinal direction is flat. Each tube 15a is laminated at a predetermined interval so that flat surfaces of its outer surface are parallel to each other and face each other.

Thus, a supercharged intake passage 15b for circulating the supercharged intake air is formed around the tube 15a, that is, between the adjacent tubes 15a.

The second intercooler 16 has a plurality of tubes 16a through which cooling water flows. The tube 16a is a flat tube whose vertical cross-sectional shape in the longitudinal direction is flat. Similarly to the tube 15a of the first intercooler 15, the tube 16a of the second intercooler 16 is laminated at a predetermined interval so that the flat surfaces of the outer surface are parallel to each other and face each other. .

Thereby, a supercharged intake passage 16b for circulating the supercharged intake air is formed around the tube 16a, that is, between the adjacent tubes 16a.

Outer fins 27 formed of the same member are disposed in the supercharging intake passage 15b and the supercharging intake passage 16b. The outer fin 27 is joined to both the

tubes

15a and 16a. Thereby, the 1st intercooler 15 and the 2nd intercooler 16 are integrated.

As the outer fin 27, a corrugated fin obtained by bending a metal thin plate having excellent heat conductivity into a wave shape is employed. The outer fins 27 are heat transfer fins that promote heat exchange between the cooling water and the supercharged intake air.

The tube 15a of the first intercooler 15, the tube 16a of the second intercooler 16, the collecting / distributing tank 26, the outer fin 27, etc. are all formed of an aluminum alloy and integrated by brazing and joining. Yes. The second intercooler 16 is disposed downstream of the first intercooler 15 in the supercharging intake air flow direction.

The tube 15a and the outer fin 27 of the first intercooler 15 constitute a heat exchange core portion 15c. The tubes 16a and the outer fins 27 of the second intercooler 16 constitute a heat exchange core portion 16c. The heat

exchange core portions

15c and 16c are portions of the

intercoolers

15 and 16 that exchange heat with refrigerant and air.

Next, the detailed configuration of the first radiator 13 and the second radiator 14 will be described. Since the configurations of the first radiator 13 and the second radiator 14 are basically the same as the configurations of the first intercooler 15 and the second intercooler 16, the first radiator 13 and the second radiator 13 are enclosed in parentheses in FIGS. Reference numerals corresponding to the two radiators 14 are attached, and illustration of the first radiator 13 and the second radiator 14 is omitted.

The first radiator 13 and the second radiator 14 of the present embodiment are each a plurality of tubes through which cooling water flows, and a collection or distribution of cooling water that is arranged at both ends of the plurality of tubes and flows through the tubes. A pair of collective distribution tanks 28 and the like. The 1st radiator 13 and the 2nd radiator 14 are comprised as what is called a tank and tube type heat exchanger.

The first radiator 13 has a plurality of tubes 13a through which cooling water flows. The tube 13a is a flat tube whose vertical cross-sectional shape in the longitudinal direction is flat. Each tube 13a is laminated at a predetermined interval so that flat surfaces of its outer surface are parallel to each other and face each other.

Thereby, the outside air passage 13b for circulating outside air is formed around the tube 13a, that is, between the adjacent tubes 13a.

The second radiator 14 has a plurality of tubes 14a for circulating cooling water therein. The tube 14a is a flat tube whose vertical cross-sectional shape in the longitudinal direction is flat. Similarly to the tube 13a of the first radiator 13, the tube 14a of the second radiator 14 is laminated at a predetermined interval so that the flat surfaces of the outer surface are parallel to each other and face each other.

Thus, an outside air passage 14b for circulating outside air is formed around the tube 14a, that is, between the adjacent tubes 14a.

Outer fins 29 formed of the same member are disposed in the outside air passage 13b and the outside air passage 14b. The outer fin 29 is joined to both the

tubes

13a and 14a. Thereby, the 1st radiator 13 and the 2nd radiator 14 are integrated.

As the outer fins 29, corrugated fins obtained by bending a metal thin plate having excellent heat conductivity into a wave shape are employed. The outer fin 29 promotes heat exchange between the cooling water and the supercharging intake air.

The tube 13a of the first radiator 13, the tube 14a of the second radiator 14, the collecting / distributing tank 28, the outer fins 29, and the like are all formed of an aluminum alloy and integrated by brazing and joining. The first radiator 13 is located downstream of the second radiator 14 in the outside air flow direction.

As shown in FIG. 4, the circulation flow path opening / closing valve 17 has one cooling water inlet 17a, two cooling

water outlets

17b, 17c, a circulation flow path side valve body 17d, and a cooling water temperature detection unit 17e.

The cooling water inlet 17 a (cooling fluid inlet) is connected to the cooling water outlet of the engine 11. The first cooling water outlet 17 b (first cooling fluid outlet) communicates with the cooling water inlet 17 a and is connected to the cooling water inlet of the first radiator 13. The second cooling water outlet 17 c communicates with the cooling water inlet 17 a and is connected to the cooling water inlet of the second intercooler 16. Therefore, the second branch portion 23 is formed inside the circulation flow path opening / closing valve 17.

The circulation channel side valve element 17d is a valve member that blocks or circulates the cooling water flow in the circulation channel 18 by opening and closing the first cooling water outlet 17b.

The cooling water temperature detector 17e is a temperature detector that detects the temperature Tw of the cooling water. For example, the cooling water temperature detection unit 17e is a thermo wax (temperature sensitive member) whose volume changes with temperature. When the volume of the cooling water temperature detector 17e changes, the circulating flow path side valve element 17d is displaced to open and close the cooling water flow path. The coolant temperature detector 17e may be a bimetal or a shape memory alloy.

Next, the operation in the above configuration will be described. In a state where the engine 11 is stopped (hereinafter referred to as an engine stop state), the engine 11 does not generate a driving force, so the pump 12 stops and the cooling water does not circulate.

When the engine is stopped, the engine 11 does not generate heat, so the cooling water temperature Tw is the same as the outside air temperature. That is, when the engine is stopped, the cooling water temperature Tw is equal to or lower than the predetermined temperature Tw1 (50 ° C. or more and 80 ° C. in the present embodiment), so the circulation flow path opening / closing valve 17 is closed.

When the engine 11 is started, the engine 11 generates driving force and heat, so that the pump 12 operates to suck or discharge the cooling water, and the cooling water temperature Tw gradually increases.

The circulation channel opening / closing valve 17 is closed until the cooling water temperature Tw reaches a predetermined temperature Tw1 (in this embodiment, 50 ° C. or more and 80 ° C.). Therefore, as shown by the thick solid line in FIG. 5, the cooling water discharged from the pump 12 flows through the engine 11 and the second intercooler 16 and is sucked into the pump 12, and the first radiator 13, the second radiator 14, and It does not circulate through the first intercooler 15.

As described above, when the engine 11 is just started, the cooling water does not flow through the first radiator 13, the second radiator 14, and the first intercooler 15, so that the heat is not radiated from the cooling water to the outside air. It can promote warm-up. On the other hand, since the cooling water flows through the second intercooler 16, the supercharged intake air can be cooled or heated.

For example, when the load of the engine 11 is high (for example, during acceleration), the supercharged intake air becomes hot. When the temperature of the supercharging intake air is higher than the temperature of the cooling water, the supercharging intake air is cooled by the second intercooler 16.

When the load on the engine 11 is low (low load), the supercharged intake air becomes cold. When the temperature of the supercharging intake air is lower than the temperature of the cooling water, the supercharging intake air is heated by the second intercooler 16. However, since the load is low, the amount of heat lost by the cooling water is small, and the warm-up is not impaired.

The engine 11 can be warmed up by the supercharged intake air heated by the second intercooler 16, and an exhaust gas emission reduction effect can be obtained.

When the cooling water temperature Tw further rises and reaches a predetermined temperature Tw1 (50 ° C. or more and 80 ° C. in the present embodiment), the circulation channel opening / closing valve 17 is opened. Therefore, the cooling water discharged from the pump 12 flows through the engine 11 and then branches into a first radiator side flow FR and a second intercooler side flow FI as shown in FIG.

The first radiator side flow FR is a flow of cooling water from the second branch portion 23 toward the first radiator 13. The second intercooler side flow FI is a flow of cooling water from the second branch portion 23 toward the second intercooler 16.

The cooling water flowing through the first intercooler 15 is cooled by the first radiator 13 and the second radiator 14. Therefore, the temperature of the cooling water flowing through the first intercooler 15 is lower than that of the cooling water flowing through the second intercooler 16.

The first radiator side flow FR further branches after flowing through the first radiator 13. Specifically, the flow FR1 that is sucked into the pump 12 as it is and the flow FR2 that flows through the second radiator 14 and the first intercooler 15 and is sucked into the pump 12 are branched.

When the supercharged intake air is at a high load, the supercharged intake air is cooled in two stages in the order of the second intercooler 16 and the first intercooler 15, so that the cooling performance is improved.

At low load when the supercharged intake air is at a low temperature, the supercharged intake air is once warmed by the second intercooler 16 and cooled by the first intercooler 15. When the load is low, the flow rate of the supercharged intake air is small. Therefore, even if the supercharged intake air is once warmed by the second intercooler 16, the supercharged air intake can be sufficiently cooled by the first intercooler 15.

In the present embodiment, a branching portion that branches the flow of cooling water flowing out from the engine 11 into a first radiator-side flow FR toward the first radiator 13 and a second intercooler-side flow FI toward the second intercooler 16. 23 and a circulation flow path opening / closing valve 17 for blocking or circulating the first radiator side flow FR.

According to this, when the circulation flow path opening / closing valve 17 blocks the first radiator side flow FR, the cooling water does not flow through the first radiator 13 and the second radiator 14. Therefore, it can suppress that heat is dissipated from the cooling water to the outside air.

Moreover, since the cooling water flows through the second intercooler 16 even if the circulation flow path opening / closing valve 17 blocks the first radiator side flow FR, the intake air of the engine 11 can be cooled.

Therefore, it is possible to suppress the warm-up performance of the engine 11 from being impaired while ensuring the cooling performance for cooling the intake air of the engine 11.

The second intercooler 16 and the first intercooler 15 of this embodiment have

tubes

15a and 16a through which cooling water flows, respectively. The tube 16a of the second intercooler 16 and the tube 15a of the first intercooler 15 are joined to each other by heat transfer fins 27 formed on a thin plate material.

According to this, since the heat exchange core portion 16c of the second intercooler 16 and the heat exchange core portion 15c of the first intercooler 15 are integrated with each other, the heat

exchange core portions

16c and 15c are separate from each other. The configuration can be simplified compared to the case where it is formed.

Moreover, since the 2nd intercooler 16 and the 1st intercooler 15 are mutually adjacent | abutted, compared with the case where the 2nd intercooler 16 and the 1st intercooler 15 are mutually spaced apart, the pressure loss of supercharging intake air is reduced. Can be reduced.

The first radiator 13 and the second radiator 14 of the present embodiment have

tubes

13a and 14a through which cooling water flows, respectively. The tube 13a of the 1st radiator 13 and the tube 14a of the 2nd radiator 14 are mutually joined by the heat-transfer fin 27 formed in the thin-plate material.

According to this, since the heat exchange core portion 13c of the first radiator 13 and the heat exchange core portion 14c of the second radiator 14 are integrated with each other, both the heat

exchange core portions

13c and 14c are formed separately from each other. The configuration can be simplified compared to the case where

Further, since the first radiator 13 and the second radiator 14 are adjacent to each other, the pressure loss of the outside air can be reduced as compared with the case where the first radiator 13 and the second radiator 14 are separated from each other.

The circulation channel opening / closing valve 17 of the present embodiment blocks or circulates the first radiator-side flow FR according to the cooling water temperature Tw detected by the cooling water temperature detection unit 17e.

Specifically, when the temperature Tw of the cooling water is lower than the predetermined temperature Tw1, the circulation flow path opening / closing valve 17 interrupts the first radiator-side flow FR, and the temperature Tw of the cooling water is equal to or higher than the predetermined temperature Tw1. The first radiator side flow FR is circulated. The predetermined temperature Tw1 is 80 ° C. or higher and 90 ° C. or lower. Thereby, it can suppress appropriately that the warming-up performance of the engine 11 is impaired.
(Second Embodiment)
In the present embodiment, as shown in FIG. 6, the heater core 30 is disposed in the second intake cooling flow path 22.

The heater core 30 is a heating heat exchanger that heats the air by exchanging heat between the cooling water flowing out from the engine 11 and the air blown into the vehicle interior. The air heated by the heater core 30 is used for air conditioning in the passenger compartment.

The heater core 30 is located upstream of the second intercooler 16 in the coolant flow direction.

The bypass flow path 31 is a flow path in which the cooling water flowing out from the heater core 30 flows around the second intercooler 16. The bypass flow path 31 branches from a portion of the second intake air cooling flow path 22 between the heater core 30 and the second intercooler 16, and the second intake air cooling flow path 22 of the second inter cooler 16 is branched. Merges downstream of the cooling water flow. The bypass flow path 31 adjusts the flow rate of the cooling water flowing through the second intercooler 16.

In the present embodiment, the second intercooler 16 is located downstream of the heater core 30 in the coolant flow direction. Therefore, the cooling water heat-exchanged by the heater core 30 flows through the second intercooler 16.

Since the cooling water dissipates heat to the air in the heater core 30, the temperature of the cooling water flowing through the second intercooler 16 is lowered. Therefore, the cooling performance of the supercharged intake air in the second intercooler 16 can be improved.

The present embodiment includes a bypass flow path 31 in which the cooling water that has flowed out of the heater core 30 flows around the second intercooler 16. Thereby, since the cooling water flow rate in the 2nd intercooler 16 can be made smaller than the cooling water flow rate in the heater core 30, the cooling performance of the supercharging intake air in the 2nd intercooler 16 can be adjusted appropriately.
(Third embodiment)
In the present embodiment, a third intercooler 32 is provided as shown in FIG. Similarly to the first intercooler 15 and the second intercooler 16, the third intercooler 32 exchanges heat between the supercharged intake air and the cooling water that have been compressed by the supercharger (turbocharger) and become high temperature. An intake air cooler that cools the intake and intake air. In order to minimize the capacity of the intake system, the third intercooler 32 is integrated with the first intercooler 15 and the second intercooler 16.

The third intercooler 32 is disposed in the third intake air cooling channel 33. The third intake air cooling flow path 33 is a flow path that branches from the circulation flow path 18 and joins the circulation flow path 18.

The third branch 34 where the third intake air cooling flow path 33 branches from the circulation flow path 18 is provided on the cooling water outlet side of the first radiator 13 and on the cooling water suction side of the pump 12. The third intake air cooling flow path 33 joins the second intake air cooling flow path 22 at the third merging portion 35, and the first intake air cooling flow path 33 passes through a part of the second intake air cooling flow path 22. 19, and further merges with the circulation channel 18 at the first junction 21 via a part of the first intake cooling channel 19.

The cooling water inlet of the third intercooler 32 is connected to the cooling water outlet of the first radiator 13. The cooling water outlet of the third intercooler 32 is connected to the cooling water inlet of the pump 12.

The third intercooler 32 is located between the first intercooler 15 and the second intercooler 16 in the supercharging intake air flow direction. Accordingly, the supercharged intake air flows in the order of the second intercooler 16, the third intercooler 32, and the first intercooler 15.

The cooling water flowing through the third intercooler 32 is cooled by the first radiator 13. Accordingly, the cooling water flowing through the third intercooler 32 has a lower temperature than the cooling water flowing through the second intercooler 16 and a higher temperature than the cooling water flowing through the first intercooler 15.

When the supercharged intake air is at a high load, the supercharged intake air is cooled in three stages in the order of the second intercooler 16, the third intercooler 32, and the first intercooler 15, so that the cooling performance is improved.

At a low load when the supercharged intake air is at a low temperature, the supercharged intake air is once warmed by the second intercooler 16 and cooled in two stages in the order of the third intercooler 32 and the first intercooler 15. When the load is low, the flow rate of the supercharged intake air is small. Therefore, even if the supercharged intake air is once warmed by the second intercooler 16, the supercharged air intake can be sufficiently cooled by the third intercooler 32 and the first intercooler 15.
(Fourth embodiment)
In the above embodiment, the second branch portion 23 where the second intake cooling flow path 22 branches from the circulation flow path 18 is the cooling water outlet side of the engine 11 and the cooling water outlet side of the first radiator 13. However, in this embodiment, as shown in FIG. 8, the second branch portion 23 is provided on the cooling water discharge side of the pump 12 and the cooling water inlet side of the engine 11.

The engine cooling circuit 10 includes a radiator bypass passage 40. The radiator bypass channel 40 is a channel through which cooling water flows by bypassing the first radiator 13 and the second radiator 14.

The radiator bypass channel 40 branches from the circulation channel 18 at the third branching portion 41 and merges with the circulation channel 18 at the third junction 42. The third branch portion 41 is provided on the cooling water outlet side of the engine 11 and on the cooling water inlet side of the circulation channel opening / closing valve 17. The third junction 42 is provided on the cooling water outlet side of the first radiator 13 and on the cooling water suction side of the pump 12.

When the circulation flow path opening / closing valve 17 is open, the flow rate of the cooling water flowing through the radiator bypass flow path 40 becomes too large, and the flow rate of the cooling water flowing through the first radiator 13 and the second radiator 14 becomes too small. The flow path resistance of the radiator bypass flow path 40 is set to be large so as not to occur.

Next, the operation in the above configuration will be described. After the engine 11 is started, the circulation flow path opening / closing valve 17 is closed until the coolant temperature Tw reaches a predetermined temperature Tw1 (in this embodiment, 50 ° C. or higher and 80 ° C.). Therefore, as shown by the thick solid line in FIG. 9, the cooling water discharged from the pump 12 flows through the second intercooler 16 and the flow through the engine 11 at the second branch portion 23 and the third branch portion 41. Are then merged at the second junction 21 and the third junction 42 and sucked into the pump 12. On the other hand, the cooling water discharged from the pump 12 does not flow to the first radiator 13, the second radiator 14, and the first intercooler 15.

When the cooling water temperature Tw further rises and reaches a predetermined temperature Tw1 (50 ° C. or more and 80 ° C. in the present embodiment), the circulation channel opening / closing valve 17 is opened. Therefore, the coolant discharged from the pump 12 flows through the engine 11 and then branches into a first radiator side flow FR and a second intercooler side flow FI as shown in FIG.

The first radiator side flow FR is a flow of cooling water from the second branch portion 23 toward the engine 11 and the first radiator 13. The second intercooler side flow FI is a flow of cooling water from the second branch portion 23 toward the second intercooler 16.

The relatively low-temperature cooling water (for example, about 70 to 80 ° C.) before passing through the engine 11 flows through the second intercooler 16. Therefore, the temperature of the cooling water flowing into the second intercooler 16 is lower than that when the high-temperature cooling water (for example, about 90 ° C.) after passing through the engine 11 flows through the second intercooler 16 as in the above embodiment. Can be suppressed.

As a result, it is possible to suppress boiling of the cooling water heat-exchanged with the high-temperature intake air (for example, about 150 to 180 ° C.) by the second intercooler 16.

In the present embodiment, the second intercooler 16 cools the intake air by exchanging heat between the cooling water flowing by bypassing the first radiator 13 and the second radiator 14 and the intake air of the engine 11. The first branching section 23 branches the flow of the cooling water into a first radiator side flow FR directed toward the first radiator 13 and a second intercooler side flow FI directed toward the second intercooler 16. The circulation flow path opening / closing valve 17 blocks or circulates the first radiator side flow FR.

According to this, similarly to the above-described embodiment, it is possible to prevent the warm-up performance of the engine 11 from being impaired while ensuring the cooling performance for cooling the intake air of the engine 11.

In the present embodiment, the first branch portion 23 is configured to change the flow of the cooling water on the cooling water outlet side of the first radiator 13 and the second radiator 14 and on the cooling water inlet side of the engine 11 to the first radiator side flow FR and the second flow. Branch to the intercooler side flow FI.

According to this, the flow of the cooling water before passing through the engine 11 can be branched into the first radiator side flow FR and the second intercooler side flow FI. Therefore, the temperature of the cooling water flowing into the second intercooler 16 is kept low compared to the case where the flow of the cooling water after passing through the engine 11 is branched into the first radiator side flow FR and the second intercooler side flow FI. be able to. Therefore, it is possible to prevent the cooling water from boiling in the second intercooler 16.
(Other embodiments)
The above embodiments can be combined as appropriate. The above embodiment can be variously modified as follows, for example.

(1) In the above embodiment, the cooling fluid is an ethylene glycol antifreeze (LLC), but the cooling fluid may be various fluids.

(2) In the above embodiment, the intake air cooling device that cools the intake air of the engine 11 that generates driving power for the vehicle has been described. However, the present invention can be widely applied to the intake air cooling device that cools the intake air of various engines (internal combustion engines). It is.

(3) In the above embodiment, the valve opening temperature Tw1 of the circulation flow path opening / closing valve 17 is set to 80 ° C. or more and 90 ° C. or less, but the valve opening temperature Tw1 of the circulation flow path opening / closing valve 17 can be variously changed. .

For example, if the opening temperature Tw1 of the circulation flow path opening / closing valve 17 is set to 50 ° C. or more and 80 ° C. or less, the circulation flow path opening / closing valve 17 is opened at a cooling water temperature Tw lower than that in the above embodiment. Then, the cooling water flows through the first intercooler 15. Therefore, compared with the said embodiment, the action | operation which gave priority to the intake air cooling performance rather than the warming-up of the engine 11 is realizable.

(4) In the above embodiment, the first intercooler 15 and the second intercooler 16 are configured as a tank-and-tube heat exchanger. However, the 1st intercooler 15 and the 2nd intercooler 16 may be constituted as a plate lamination type heat exchanger.

The plate-stacked heat exchanger is a heat exchanger in which a plurality of substantially flat heat transfer plates are stacked with a space therebetween, and a heat exchange fluid channel is formed between the heat transfer plates.

In the above embodiment, the first radiator and the second radiator are also configured as a tank-and-tube heat exchanger, but the first radiator and the second radiator may also be configured as a plate-stacked heat exchanger. .

(5) In the above embodiment, the heat exchange core portion 16c of the second intercooler 16 and the heat exchange core portion 15c of the first intercooler 15 are integrated. However, the second intercooler 16 and the first intercooler 15 may be formed separately from each other and may be separated from each other in the flow direction of the intake air.

According to this, the freedom degree of arrangement | positioning of the 2nd intercooler 16 and the 1st intercooler 15 can be raised.

(6) In the above embodiment, the heat exchange core portion 13c of the first radiator 13 and the heat exchange core portion 14c of the second radiator 14 are integrated. However, the first radiator 13 and the second radiator 14 may be formed separately from each other and may be separated from each other in the flow direction of the intake air.

According to this, the freedom degree of arrangement | positioning of the 1st radiator 13 and the 2nd radiator 14 can be raised.

Claims

A first radiator (13) that cools the cooling fluid by exchanging heat between the cooling fluid flowing out of the engine (11) and the outside air;
A second radiator (14) for cooling the cooling fluid by exchanging heat between the cooling fluid cooled by the first radiator (13) and the outside air;
A first intake air cooler (15) for exchanging heat between the cooling fluid cooled by the second radiator (14) and the intake air of the engine (11) to cool the intake air;
A second intake air cooler (16) that cools the intake air by exchanging heat between the cooling fluid flowing by bypassing the first radiator (13) and the second radiator (14) and the intake air of the engine (11). )When,
The flow of the cooling fluid is divided into a first radiator side flow (FR) toward the first radiator (13) and a second intake air cooler side flow (FI) toward the second intake air cooler (16). A branching section (23) for branching;
An intake air cooling apparatus comprising: a switching unit (17) for blocking or circulating the first radiator side flow (FR).
A first radiator (13) that cools the cooling fluid by exchanging heat between the cooling fluid flowing out of the engine (11) and the outside air;
A second radiator (14) for cooling the cooling fluid by exchanging heat between the cooling fluid cooled by the first radiator (13) and the outside air;
A first intake air cooler (15) for exchanging heat between the cooling fluid cooled by the second radiator (14) and the intake air of the engine (11) to cool the intake air;
A second intake air cooler (16) that cools the intake air by exchanging heat between the cooling fluid flowing out of the engine (11) and the intake air of the engine (11);
The cooling fluid flowing out of the engine (11) is divided into a first radiator side flow (FR) toward the first radiator (13) and a second intake air cooling toward the second intake air cooler (16). A branch part (23) for branching into the vessel side flow (FI),
An intake air cooling apparatus comprising: a switching unit (17) for blocking or circulating the first radiator side flow (FR).
The branch (23) is configured to flow the cooling fluid on the outlet side of the first radiator (13) and the second radiator (14) and on the inlet side of the engine (11) on the first radiator side flow ( FR) and the second intake air cooler side flow (FI) are branched.
A heater core (30) for heating the air by exchanging heat between the cooling fluid that has flowed out of the engine (11) and the air blown into the vehicle interior;
The intake air cooling device according to any one of claims 1 to 3, wherein the second intake air cooler (16) is located downstream of the heater core (30) in the flow direction of the cooling fluid.
The intake air cooling device according to claim 4, further comprising a bypass channel (31) through which the cooling fluid flowing out of the heater core (30) flows around the second intake air cooler (16).
The second intake air cooler (16) and the first intake air cooler (15) each have tubes (15a, 16a) through which cooling fluid flows,
The tube (16a) of the second intake air cooler (16) and the tube (15a) of the first intake air cooler (15) are joined together by heat transfer fins (27) formed in a thin plate material. Item 6. The intake air cooling device according to any one of Items 1 to 5.
The second intake air cooler (16) and the first intake air cooler (15) are formed separately from each other and are separated from each other in the flow direction of the intake air. The intake air cooling device according to one.
The first radiator (13) and the second radiator (14) each have tubes (13a, 14a) through which a cooling fluid flows,
The tube (13a) of the first radiator (13) and the tube (14a) of the second radiator (14) are joined to each other by heat transfer fins (27) formed in a thin plate material. The intake air cooling device according to any one of the above.
The first radiator (13) and the second radiator (14) are formed separately from each other and are separated from each other in the flow direction of the intake air. Intake cooling system.
A temperature detector (17e) for detecting the temperature (Tw) of the cooling fluid;
The switching unit (17) according to any one of claims 1 to 9, wherein the first radiator side flow (FR) is cut off or circulated according to a temperature (Tw) detected by the temperature detector (17e). The intake air cooling device described.
When the temperature (Tw) detected by the temperature detector (17e) is lower than a predetermined temperature (Tw1), the switching unit (17) shuts off the first radiator side flow (FR), and the temperature detector When the temperature (Tw) detected by (17e) is equal to or higher than the predetermined temperature (Tw1), the first radiator side flow (FR) is circulated,
The intake air cooling device according to claim 10, wherein the predetermined temperature (Tw1) is 80 ° C or higher and 90 ° C or lower.
When the temperature (Tw) detected by the temperature detector (17e) is lower than a predetermined temperature (Tw1), the switching unit (17) shuts off the first radiator side flow (FR), and the temperature detector When the temperature (Tw) detected by (17e) is equal to or higher than the predetermined temperature (Tw1), the first radiator side flow (FR) is circulated,
The intake air cooling device according to claim 10, wherein the predetermined temperature (Tw1) is 50 ° C or higher and 80 ° C or lower.