WO2019123970A1

WO2019123970A1 - Cool circuit and oil cooler

Info

Publication number: WO2019123970A1
Application number: PCT/JP2018/043173
Authority: WO
Inventors: 宮川　雅志
Original assignee: 株式会社デンソー
Priority date: 2017-12-22
Filing date: 2018-11-22
Publication date: 2019-06-27
Also published as: JP2019112981A; US20200318529A1; JP6919552B2; CN111542688A

Abstract

This oil cooler comprises a plurality of plates arranged in layers, alternately providing oil flow passageways for circulation of oil and cooling water flow passageways for circulation of cooling water. A cooling water plate (70) configuring the cooling water flow passageways is provided with: an inner flow passageway (77) for flowing a cooling water; a first cooling water inflow passageway (72a) and a second cooling water inflow passageway (73a) for the inflow of the cooling water into the inner flow passageway; and a first cooling water outflow passageway (72b) and a second cooling water outflow passageway (73b) for the outflow of the cooling water from the inner flow passageway.

Description

Cooling circuit and oil cooler

Cross-reference to related applications

This application is based on Japanese Patent Application No. 2017-245714 filed on Dec. 22, 2017 and claims the benefit of its priority, and the entire contents of the patent application are as follows: Incorporated herein by reference.

The present disclosure relates to a cooling circuit and an oil cooler.

Conventionally, there is an oil cooler described in Patent Document 1 below. The oil cooler described in Patent Document 1 has a heat exchanger core formed by stacking a large number of plates, and a flow path control valve attached to the top. The flow control valve includes a valve housing and a rotary valve brazed to the top of the plate, and a low temperature cooling water inlet to which low temperature cooling water is supplied, and a high temperature cooling water inlet to which high temperature cooling water is supplied , And a cooling water outlet for returning the cooling water. The core coolant inlet and the core coolant outlet of the heat exchanger core are in communication with the interior of the valve housing. These flow paths appropriately communicate with each other according to the switching position of the rotary valve to heat and cool the oil.

JP 2012-57889 A

In the oil cooler as described in Patent Document 1, the flow rate of the cooling water used differs depending on the case of heating the oil and the case of cooling the oil. Specifically, the flow rate of the low temperature cooling water used in cooling the oil tends to be larger than the flow rate of the high temperature cooling water used in heating the oil. In the oil cooler described in Patent Document 1, cooling is performed from one cooling water outlet either at the time of oil heating with a relatively low flow rate of cooling water and at the time of oil cooling with a relatively high flow rate of cooling water. Water is drained. Therefore, the pressure loss of the cooling water tends to be large particularly when cooling oil with a large flow rate of the cooling water. When the pressure loss of the cooling water increases, the flow velocity of the cooling water decreases, which may cause problems such as a decrease in heat exchange performance of the oil cooler, an increase in a pump load, and the like.

An object of the present disclosure is to provide an oil cooler and a cooling circuit capable of reducing pressure loss while allowing flow rate change.

The cooling circuit according to one aspect of the present disclosure includes a first cooling water flow path through which the first cooling water flows, a second cooling water flow path through which the second cooling water flows, and the temperature of the inflowing cooling water is less than a predetermined temperature. A thermostat for blocking the flow of the first cooling water in the first cooling water flow path, and heating the oil, a thermostat allowing the flow of the first cooling water in the first cooling water flow path when the temperature of the cooling water is equal to or higher than a predetermined temperature. Or an oil cooler for cooling. The oil cooler has a first cooling water inlet through which the first cooling water flowing through the first cooling water flow channel, and a first cooling water outlet through which the cooling water flowing through the oil cooler flows out to the first cooling water flow channel, A second cooling water inlet through which the second cooling water flowing through the second cooling water flow channel flows, and a second cooling water outlet through which the cooling water flowing through the inside of the oil cooler flows out to the second cooling water flow channel; The oil is heated or cooled by heat exchange between the oil and the cooling water flowing in from at least one of the first cooling water inlet and the second cooling water inlet.

According to this configuration, when the flow of the first cooling water in the first cooling water flow path is blocked by the thermostat, only the second cooling water flows into the oil cooler. On the other hand, when circulation of the first cooling water in the first cooling water flow path is permitted by the thermostat, both the first cooling water and the second cooling water flow into the oil cooler. Thus, the flow rate of the cooling water flowing through the oil cooler can be changed. Further, since the cooling water can be made to flow out from the two outlets of the first cooling water outlet and the second cooling water outlet, compared with the conventional oil cooler having only one outlet, the cooling water Pressure loss can be reduced.

An oil cooler according to an aspect of the present disclosure is an oil cooler in which an oil flow path through which oil flows and a cooling water flow path through which cooling water flows are alternately provided by stacking and arranging a plurality of plates. The cooling water plate constituting the cooling water flow path is an internal flow path through which the cooling water flows, a first cooling water inflow path and a second cooling water inflow path through which the cooling water flows into the internal flow path, and an internal flow path And a first cooling water outlet and a second cooling water outlet for discharging the cooling water therefrom.

According to this configuration, for example, if the cooling water does not flow into the first cooling water inflow path, the cooling water flows into the internal flow path only from the second cooling water inflow path. On the other hand, when the cooling water flows into the first cooling water inflow path, the cooling water flows from both the first cooling water inflow path and the second cooling water inflow path to the internal flow path. Therefore, the flow rate of the cooling water flowing through the internal flow path can be changed. Further, since the cooling water can be made to flow out from the two outflow passages of the first cooling water outflow passage and the second cooling water outflow passage, compared with the conventional oil cooler having only one outflow passage, Pressure loss can be reduced.

FIG. 1 is a block diagram showing a schematic configuration of the cooling circuit of the first embodiment. FIG. 2 is a cross-sectional view showing a cross-sectional structure of the oil cooler of the first embodiment. FIG. 3 is a perspective view showing a perspective view of the offset fin of the first embodiment. FIG. 4 is a block diagram showing an operation example of the cooling circuit of the first embodiment. FIG. 5 is a time chart showing the transition of the temperature of the cooling water of the engine of the first embodiment and the temperature of the oil of the transmission. FIG. 6 is a block diagram showing an operation example of the cooling circuit of the first embodiment. FIG. 7 is a block diagram showing a schematic configuration of the cooling circuit of the second embodiment.

Hereinafter, embodiments of the cooling circuit and the oil cooler will be described with reference to the drawings. In order to facilitate understanding of the description, the same constituent elements in the drawings are denoted by the same reference numerals as much as possible, and redundant description will be omitted.
First Embodiment
First, a first embodiment of the cooling circuit and the oil cooler will be described.

The cooling circuit 10 of the present embodiment shown in FIG. 1 is mounted on a vehicle, and includes an engine cooling circuit 20 in which cooling water of the engine 40 circulates and a transmission cooling circuit in which hydraulic oil of the transmission 50 circulates. And 30.
The engine cooling circuit 20 is provided with an engine 40, a radiator 41, a heater core 42, a thermostat 43, and a cooling water pump 44.

The engine 40 is connected to the radiator 41 through the cooling water flow path W20. In addition, the engine 40 is connected to the heater core 42 through the cooling water flow path W21. Therefore, the cooling water heat-exchanged with the engine 40 can flow to at least one of the radiator 41 and the heater core 42 through the cooling water flow path W20 and the cooling water flow path W21. In the present embodiment, the cooling water flow path W20 corresponds to a first cooling water flow path, and the cooling water flowing through the cooling water flow path W20 corresponds to a first cooling water.

The radiator 41 cools the cooling water by heat exchange between the cooling water flowing inside and the air flowing outside. The cooling water cooled by the radiator 41 flows into the cooling water pump 44 through the cooling water flow path W22.
The cooling water pump 44 is a mechanical pump driven on the basis of the power transmitted from the engine 40 or an electric pump driven on the basis of the power supplied from a battery mounted on the vehicle. The cooling water pump 44 circulates the cooling water to each element of the engine cooling circuit 20 by pressure-feeding the inflowing cooling water to the engine 40.

The heater core 42 is a component of an air conditioner of a vehicle. The heater core 42 heats the air flowing in the air conditioning duct by performing heat exchange between the cooling water supplied from the engine 40 and the air flowing in the air conditioning duct of the air conditioner. In the air conditioner, the heated air is blown out into the vehicle compartment through the air conditioning duct to heat the vehicle interior. The cooling water having flowed inside the heater core 42 flows into the thermostat 43 through the cooling water flow path W23. In the present embodiment, the cooling water flow path W23 corresponds to a second cooling water flow path, and the cooling water flowing through the cooling water flow path W23 corresponds to a second cooling water.

The thermostat 43 is provided in the middle of the cooling water flow path W22 which connects the radiator 41 and the engine 40. When the temperature of the cooling water is lower than the predetermined valve opening temperature Tth1, the thermostat 43 is in a valve closed state in which the cooling water flow path W22 is shut off. The valve opening temperature Tth1 is set to, for example, 80 degrees. When the temperature of the cooling water is less than the valve opening temperature Tth1, the flow of the cooling water from the heater core 42 to the engine 40 is permitted, while the flow of the cooling water from the radiator 41 to the engine 40 is blocked. When the temperature of the cooling water is equal to or higher than the valve opening temperature Tth1, the thermostat 43 is in an open state in which the cooling water flow path W22 is opened. When the temperature of the cooling water is equal to or higher than the valve opening temperature Tth1, the flow of the cooling water from the heater core 42 to the engine 40 is permitted, and the flow of the cooling water from the radiator 41 to the engine 40 is also permitted. When the temperature of the cooling water exceeds a fully open temperature Tth2 higher than the valve opening temperature Tth1, the thermostat 43 is fully opened.

In the engine cooling circuit 20, the thermostat 43 is closed when the temperature of the cooling water is low, such as when the engine 40 is cold-started. Therefore, the cooling water pumped by the cooling water pump 44 circulates through the engine 40 and the heater core 42 which are elements other than the radiator 41. Therefore, since the cooling water is not cooled in the radiator 41, the temperature of the cooling water can be easily raised early. As a result, the engine 40 and the heater core 42 tend to be warmed up early.

Thereafter, when the temperature of the cooling water rises to the valve opening temperature Tth1 or more, the thermostat 43 is opened. Therefore, the cooling water pumped by the cooling water pump 44 circulates through the engine 40, the radiator 41, and the heater core 42. As a result, the cooling water cooled in the radiator 41 is supplied to the engine 40, and the engine 40 is cooled by heat exchange with the engine 40. Moreover, since a part of the cooling water heated by flowing through the inside of the engine 40 is supplied to the heater core 42, the temperature of the heater core 42 is maintained at a high temperature. Therefore, the air flowing in the air conditioning duct can be heated by the heater core 42.

The transmission cooling circuit 30 is provided with a transmission 50, an oil cooler 51, and an oil pump 52.
The transmission 50 is connected to the oil inflow port 510 a of the oil cooler 51 through the oil flow path W <b> 30. The oil having flowed through the inside of the transmission 50 flows into the oil inflow port 510a of the oil cooler 51 through the oil flow path W30.

The oil cooler 51 includes an oil inlet 510a, a first cooling water inlet 511a, a second cooling water inlet 512a, an oil outlet 510b, a first cooling water outlet 511b, and a second cooling water outlet 512b.
The oil flowing into the oil inlet 510a flows through the inside of the oil cooler 51 and is then discharged from the oil outlet 510b. The oil discharged from the oil outlet 510b flows into the oil pump 52 through the oil passage W31.

The oil pump 52 is an electrically driven pump driven based on the power supplied from, for example, a battery mounted on a vehicle. The oil pump 52 circulates the oil to each element of the transmission cooling circuit 30 by pressure-feeding the inflowing oil to the transmission 50.
The first coolant inlet port 511a of the oil cooler 51 is connected to the coolant channel W20 through the bypass channel W40. Therefore, part of the cooling water flowing through the cooling water flow path W20, that is, part of the cooling water discharged from the engine 40 flows into the oil cooler 51 through the bypass flow path W40. A check valve 45 is provided in the middle of the bypass flow passage W40. The check valve 45 permits the circulation of the cooling water in the direction from the cooling water flow path W20 toward the first cooling water inlet 511a, while the cooling water in the direction from the first cooling water flow inlet 511a toward the cooling water flow path W20. Regulating distribution. In the present embodiment, the check valve 45 corresponds to the flow control portion.

The second cooling water inflow port 512 a of the oil cooler 51 is connected to the cooling water flow path W 23 through the bypass flow path W 41. Therefore, a part of the cooling water flowing through the cooling water flow path W23, that is, a part of the cooling water discharged from the heater core 42 flows into the oil cooler 51 through the bypass flow path W41.

The cooling water which has flowed into the inside of the oil cooler 51 from at least one of the first cooling water inlet 511 a and the second cooling water inlet 512 a exchanges heat with the oil flowing through the oil cooler 51. This heats or cools the oil. The cooling water having flowed inside the oil cooler 51 is discharged from the first cooling water outlet 511b or the second cooling water outlet 512b. The first coolant outlet 511b is connected to a portion on the downstream side of a portion of the coolant channel W20 connected to the bypass channel W40 through the bypass channel W42. Therefore, the cooling water discharged from the first cooling water outlet 511b flows into the cooling water channel W20. The second coolant outlet 512b is connected to a portion on the downstream side of a portion of the coolant channel W23 connected to the bypass channel W41 through the bypass channel W43. Therefore, the cooling water discharged from the second cooling water outlet 512b flows into the cooling water channel W23.

Next, the specific structure of the oil cooler 51 will be described.
The oil cooler 51 has a structure in which oil flow paths through which oil flows and cooling water flow paths through which cooling water flows are alternately provided by arranging a plurality of plates in a stacked manner. FIG. 2 shows the cross-sectional structure of the cooling water plate 70 that constitutes the cooling water flow path of the oil cooler 51. As shown in FIG.

As shown in FIG. 2, in the cooling water plate 70, the cross-sectional shape orthogonal to the plate stacking direction is formed in a substantially hexagonal shape. An internal flow passage 77 through which the cooling water flows is formed in the cooling water plate 70. In the cooling water plate 70, there are a first cooling water inflow passage 72a, a second cooling water inflow passage 73a, a first cooling water outflow passage 72b, and a second cooling water outflow passage 73b communicating with the cooling water internal flow passage 77. It is provided. Further, the cooling water plate 70 is provided with an oil inflow passage 71 a and an oil outflow passage 71 b which are not communicated with the cooling water internal passage 77. The first cooling water inflow path 72 a is provided at the corner C 1 of the cooling water plate 70. An oil outflow passage 71 b and a second cooling water inflow passage 73 a are respectively provided at two corner portions C 2 and C 3 adjacent to the corner portion C 1 in the cooling water plate 70. A first cooling water outflow passage 72b, an oil inflow passage 71a, and a second cooling water outflow passage 73b are provided at angles C4 to C6 located diagonally of the corners C1 to C3 in the cooling water plate 70. The inner diameter of the first coolant inlet channel 72a is larger than the inner diameter of the second coolant inlet channel 73a. Similarly, the inner diameter of the first coolant outlet channel 72b is larger than the inner diameter of the second coolant outlet channel 73b.

Hereinafter, the direction from the first cooling water inflow passage 72a toward the first cooling water outflow passage 72b is referred to as "X direction", and the direction orthogonal to the X direction is referred to as "Y direction". Further, the direction from the second cooling water inflow path 73a toward the second cooling water outflow path 73b, that is, the direction that bisects the X direction and the Y direction is referred to as an "α direction". In the present embodiment, the X direction corresponds to the first direction, the Y direction corresponds to the second direction, and the α direction corresponds to the third direction.

Offset fins 74 are disposed in the cooling water internal flow passage 77 of the cooling water plate 70. As shown in FIG. 3, the offset fin 74 has a plurality of partially cut and raised cut-and-raised portions 740 in the X direction. The X direction is the opening direction of the offset fin 74. The cut-and-raised

portions

740 and 740 adjacent to each other in the X direction are arranged to be offset in the Y direction. In this offset fin 74, when the cooling water is flowing in the X direction shown in FIG. 2, that is, when the cooling water flows from the first cooling water inflow passage 72a toward the first cooling water outflow passage 72b, Since the cooling water flows through the inside of the cut and raised portion 740 and the gap between the adjacent cut and raised

portions

740 and 740, the water flow resistance acting on the cooling water is small. On the other hand, when the cooling water is flowing in the α direction, that is, when the cooling water flows from the second cooling water inflow path 73a toward the second cooling water outflow path 73b, the cooling water is Since it is easy to collide, the water flow resistance acting on the cooling water becomes large. In the present embodiment, the offset fins 74 correspond to a water flow resistance applying portion.

A rib 75 is formed between the first cooling water inflow passage 72 a and the second cooling water inflow passage 73 a in the cooling water plate 70 so as to extend from the inner wall surface of the cooling water plate 70. The rib 75 suppresses the short circuit of the flow of the cooling water between the first cooling water inflow path 72a and the second cooling water inflow path 73a.

Similarly, a rib 76 is formed between the first coolant outlet passage 72 b and the second coolant outlet passage 73 b in the coolant plate 70 so as to extend from the inner wall surface of the coolant plate 70. The rib 76 suppresses a short circuit of the flow of the cooling water between the first cooling water outflow passage 72b and the second cooling water outflow passage 73b.

In the oil cooler 51, oil flows into the oil inflow path 71a shown in FIG. 2 from the oil inflow port 510a shown in FIG. The oil that has flowed into the oil inflow path 71 a flows into the oil internal flow path formed in the oil plate adjacent to the cooling water plate 70. As shown in FIG. 2, the oil flowing in the internal oil flow path flows in the direction indicated by the arrow D1 in the figure. The flow direction D1 of the oil is opposed to the flow direction D2 of the cooling water from the first cooling water inflow path 72a toward the first cooling water outflow path 72b. The oil that has flowed into the oil internal flow path is discharged from the oil outlet 510b shown in FIG. 1 through the oil outflow path 71b.

Next, an operation example of the cooling circuit 10 and the oil cooler 51 of the present embodiment will be described.
When the temperature of the coolant flowing through the engine cooling circuit 20 is less than the valve opening temperature Tth1, for example, at the time of cold start of the engine 40, the thermostat 43 is in the valve closed state. In this case, the cooling water circulates in the engine cooling circuit 20 as shown by a thick line in FIG. That is, while the cooling water circulates through the engine 40, the heater core 42, the oil cooler 51, the thermostat 43, and the cooling water pump 44, the cooling water does not circulate through the radiator 41.

In this case, the coolant heated by heat exchange with the engine 40 flows into the second coolant inlet 512a of the oil cooler 51 through the coolant channel W21, the heater core 42, the coolant channel W23, and the bypass channel W41. It flows through the cooling water internal flow passage 77 of the cooler 51. The heat is exchanged between the cooling water flowing through the cooling water internal flow passage 77 of the oil cooler 51 and the oil flowing through the oil internal flow passage, whereby the oil is heated. That is, the oil flowing through the transmission 50 can be heated. The cooling water whose temperature has decreased due to the heat exchange with the oil is discharged to the bypass flow passage W43 through the second cooling water outflow passage 73b and the second cooling water flow outlet 512b. The cooling water discharged to the bypass flow path W43 is heated again by flowing into the engine 40 through the cooling water flow path W23, the thermostat 43, and the cooling water pump 44.

In the oil cooler 51, since the cooling water is flowing from the second cooling water inflow path 73a toward the second cooling water outflow path 73b, the cooling water is likely to receive the water flow resistance from the offset fins 74. Therefore, the flow rate of the cooling water flowing in the oil cooler 51 is reduced. In this respect, as shown in FIG. 5, when the engine 40 is started at time t10, for example, the temperature Te of the cooling water of the engine 40 rises earlier than the temperature Tt of the oil of the transmission 50. Therefore, the temperature difference ΔT between the temperature Te of the cooling water of the engine 40 and the temperature Tt of the oil of the transmission 50 becomes large, so even if the flow rate of the cooling water flowing in the oil cooler 51 is small, heating of the oil Is possible.

Thereafter, when the temperature of the cooling water flowing through the engine cooling circuit 20 rises to the valve opening temperature Tth1 or more, the thermostat 43 is opened. In this case, the cooling water circulates in the engine cooling circuit 20 as shown by a thick line in FIG. That is, the cooling water circulates through all the elements of the engine cooling circuit 20.

In this case, the cooling water cooled in the radiator 41 flows into the first cooling water inlet 511a of the oil cooler 51 through the engine 40, the cooling water passage W20, and the bypass passage W40. Further, the cooling water flowing through the cooling water flow path W23 flows into the second cooling water inflow port 512a of the oil cooler 51 through the bypass flow path W41. The cooling water flowing into the first cooling water inlet 511 a and the second cooling water inlet 512 a flows in the cooling water internal flow passage 77 of the oil cooler 51. The heat is exchanged between the cooling water flowing through the cooling water internal flow passage 77 and the oil flowing through the oil internal flow passage, whereby the oil is cooled. That is, the oil flowing through the transmission 50 is cooled. Therefore, as shown in FIG. 5, after time t11 at which the temperature of the cooling water exceeds the valve opening temperature Tth1, the temperature Tt of the oil of the transmission 50 decreases.

The coolant heated by heat exchange of oil is discharged to the bypass channel W42 through the first coolant inlet channel 72a and the first coolant outlet 511b, or the second coolant outlet channel 73b and the second coolant The water is discharged from the water outlet 512b into the bypass channel W43. The cooling water discharged to the bypass flow path W42 is cooled again by flowing into the radiator 41 through the cooling water flow path W20.

According to the cooling circuit 10 and the oil cooler 51 of the present embodiment described above, the actions and effects shown in the following (1) to (6) can be obtained.
(1) When the flow of cooling water in the cooling water flow path W20 is blocked by the thermostat 43, the cooling water does not flow into the first cooling water inflow path 72a of the oil cooler 51. The cooling water flows in only from the second cooling water inflow path 73a. On the other hand, when circulation of the cooling water in the cooling water flow path W20 is permitted by the thermostat 43, the internal flow path 77 of the oil cooler 51 includes the first cooling water inflow path 72a and the second cooling water inflow path 73a. Cooling water flows from both sides. Thus, the flow rate of the cooling water flowing through the oil cooler 51 can be changed. Further, the oil cooler 51 is supplied with cooling water from the two outlets of the first cooling water outlet 511b and the second cooling water outlet 512b, and the two outlets of the first cooling water outlet 72b and the second cooling water outlet 73b. As it can be drained out, the pressure loss of the cooling water can be reduced compared to a conventional oil cooler having only one outlet and one outlet.

(2) A check valve 45 is provided in the bypass channel W40 connecting the first coolant inlet 511a of the oil cooler 51 and the coolant channel W20. The check valve 45 regulates the flow of the cooling water in the direction from the first cooling water inlet 511 a of the oil cooler 51 toward the cooling water flow path W <b> 20. Thereby, when the thermostat 43 is in the valve closed state, it is possible to prevent the cooling water flowing in the internal flow passage 77 of the oil cooler 51 from flowing back toward the cooling water flow passage W20.

(3) In the oil cooler 51, the cooling water which has flowed into the first cooling water inflow path 72a from the first cooling water inflow port 511a is discharged from the first cooling water outflow port 511b through the first cooling water outflow path 72b. The flow direction D2 of the cooling water and the flow direction D1 of the oil face each other. As a result, heat exchange can be performed more efficiently between the cooling water and the oil, so that the oil cooling efficiency can be enhanced.

(4) The cooling water plate 70 of the oil cooler 51 has offset fins 74. When the offset fins 74 flow in the X direction, which is a direction from the first cooling water inflow path 72a toward the first cooling water outflow path 72b, a water flow resistance received by the cooling water, and a second cooling water inflow path 73a to the second cooling When flowing in the α direction, which is a direction toward the water outflow path 73b, the flow resistance to be received by the cooling water is made different. Specifically, the latter is larger than the former. As a result, the cooling water can easily flow from the first cooling water inflow path 72a toward the first cooling water outflow path 72b, so the cooling water in the oil cooler 51 can easily flow to the radiator 41. As a result, since the cooling water in the cooling circuit 10 can be easily cooled, the cooling efficiency of the cooling circuit 10 can be enhanced. Further, the flow resistances in two directions can be easily made different only by arranging the offset fins 74 inside the cooling water plate 70.

(5) In the oil cooler 51, the first cooling water inflow passage 72a and the first cooling water outflow passage 72b are disposed to face each other with the offset fin 74 interposed therebetween in the X direction. Further, the second cooling water inflow path 73a and the second cooling water outflow path 73b are disposed to face each other across the offset fin 74 in the α direction. Thus, the flow resistance on the cooling water flowing in the X direction is made different from the flow resistance on the cooling water flowing in the α direction, while maintaining high heat exchange efficiency between the cooling water and the oil. Can.

(6) A rib 75 is provided between the first cooling water inflow passage 72a and the second cooling water inflow passage 73a in the oil cooler 51. Since a short circuit of the flow of the cooling water between the first cooling water inflow path 72a and the second cooling water inflow path 73a can be suppressed by the rib 75, the reduction of the heat exchange efficiency of the oil cooler 51 is suppressed. Can.

Second Embodiment
Next, a second embodiment of the cooling circuit 10 will be described. Hereinafter, differences from the cooling circuit 10 of the first embodiment will be mainly described. In addition, the engine 40 of this embodiment is an engine with a supercharger.

As shown in FIG. 7, the cooling circuit 10 of the present embodiment is provided with a CAC cooling circuit 80 in which the cooling water of the charge air cooler (CAC) 81 circulates instead of the circuit flowing through the heater core 42. ing. The CAC cooling circuit 80 is provided with a CAC 81, a low water temperature radiator 82, a cooling water pump 83, and a thermostat 84.

The CAC 81 is a device that raises the air density by cooling the intake air compressed in the supercharged engine 40. Cooling water is circulated between the CAC 81 and the low water temperature radiator 82 through the cooling water flow paths W50 and W51. The low water temperature radiator 82 cools the cooling water by performing heat exchange between the cooling water flowing inside and the air flowing outside.

The coolant pump 83 is provided in the coolant channel W51. The cooling water pump 83 circulates the cooling water in the CAC cooling circuit 80.
The second coolant inlet 512a of the oil cooler 51 is connected to the coolant channel W50 through the coolant channel W52. The second coolant outlet 512b of the oil cooler 51 is connected to the coolant channel W51 through the coolant channel W53. In the present embodiment, the cooling water passage W52 corresponds to a second cooling water passage, and the cooling water flowing inside the cooling water passage W52 corresponds to a second cooling water.

The thermostat 84 is provided at a connection portion of the cooling water passage W50 with the cooling water passage W52. The thermostat 84 is in a closed state when the temperature of the cooling water is lower than the predetermined temperature, and blocks the flow of the cooling water in the cooling water flow path W50. The thermostat 84 is opened when the temperature of the cooling water is equal to or higher than a predetermined temperature, and permits the flow of the cooling water in the cooling water flow path W50.

In the cooling circuit 10 of the present embodiment, the cooling water flow path W20 is connected to the cooling water flow path W22 through the cooling circuit W24. The cooling circuit W24 is a flow path for causing the cooling water flowing in the cooling water flow path W20 to bypass the radiator 41 and flow in the cooling water flow path W22.
According to such a configuration, when the

thermostats

43 and 84 are in the valve closed state, the cooling water heated by heat exchange with the CAC 81 is supplied to the oil cooler 51. Therefore, the oil cooler 51 can heat the oil by heat exchange between the cooling water and the oil.

Other Embodiments
In addition, each embodiment can also be implemented in the following modes.
In the bypass flow passage W40, a solenoid valve may be provided instead of the check valve 45 as a flow control unit that restricts the flow of the cooling water.

The oil cooled by the oil cooler 51 is not limited to the oil used for the transmission 50, and may be oil used for a power machine such as the engine 40 or the like.
The cooling circuit 10 may be configured to cool a motor mounted on a vehicle, an inverter device for driving the motor, or the like, instead of the engine 40.

The cooling water plate 70 may be provided with an appropriate structure other than the offset fins as a water flow resistance applying portion.
The present disclosure is not limited to the above specific example. Those skilled in the art may appropriately modify the above-described specific example as long as the features of the present disclosure are included. The elements included in the specific examples described above, and the arrangement, conditions, shape, and the like of the elements are not limited to those illustrated, and can be changed as appropriate. The elements included in the above-described specific examples can be appropriately changed in combination as long as no technical contradiction arises.

Claims

A first coolant flow path (W20) through which the first coolant flows;
A second coolant flow path (W23, W52) through which the second coolant flows;
The flow of the first cooling water in the first cooling water flow path is blocked when the temperature of the inflowing cooling water is less than a predetermined temperature, and the first cooling is performed when the temperature of the cooling water is equal to or higher than the predetermined temperature A thermostat (43) for permitting the flow of the first cooling water in the water flow path;
An oil cooler (51) for heating or cooling the oil;
The oil cooler is
A first coolant inlet (511a) into which the first coolant flows in the first coolant channel;
A first coolant outlet (511b) for causing the coolant flowing through the inside of the oil cooler to flow out to the first coolant channel;
A second coolant inlet (512a) into which the second coolant flows in the second coolant flow path;
And a second coolant outlet (512b) for causing the coolant flowing inside the oil cooler to flow out to the second coolant channel.
A cooling circuit heating or cooling the oil by heat exchange between the oil and the cooling water flowing in from at least one of the first cooling water inlet and the second cooling water inlet.
A bypass channel (W40) connecting the first coolant inlet to the first coolant channel;
A flow control unit (45) provided in the bypass flow path, for restricting the flow of the first cooling water in a direction from the first cooling water inlet toward the first cooling water flow path;
The cooling circuit of claim 1 further comprising:
The cooling circuit according to claim 2, wherein the flow control unit comprises a check valve.
4. The oil cooler according to claim 1, wherein the flow direction of the cooling water flowing from the first cooling water inlet to the first cooling water outlet is opposite to the flow direction of the oil. Cooling circuit.
The cooling circuit according to any one of claims 1 to 4, wherein the oil is an oil used for a transmission (50) of a vehicle.
The cooling circuit according to any one of claims 1 to 4, wherein the oil is an oil used for a power machine of a vehicle.
An oil cooler (51) in which an oil flow path through which oil flows and a cooling water flow path through which cooling water is alternately provided by stacking and arranging a plurality of plates,
The cooling water plate (70) constituting the cooling water flow path is
An internal flow path (77) through which the cooling water flows,
A first cooling water inflow path (72a) and a second cooling water inflow path (73a) for causing the cooling water to flow into the internal flow path;
A first coolant outlet channel (72b) and a second coolant outlet channel (73b) for causing the coolant to flow out from the internal channel;
Oil cooler with
The cooling water plate is
A flow resistance, which the cooling water receives when flowing in a first direction from the first cooling water inflow path to the first cooling water outflow path, and a second flow from the second cooling water inflow path to the second cooling water outflow path The oil cooler according to claim 7, further comprising a water flow resistance applying portion (74) that makes the flow resistance different from that received by the cooling water when flowing in two directions.
In the water flow resistance applying portion, a plurality of partially cut and raised cut and raised portions are formed in the first direction, and the cut and raised portions adjacent to each other in the first direction are arranged to be offset from each other The oil cooler according to claim 8, which is an offset fin.
A direction perpendicular to the first direction, in which adjacent cut-and-raised portions are offset from each other, is a second direction, and a direction dividing the first direction and the second direction into third directions is a third direction. And when
The first cooling water inflow path and the first cooling water outflow path are disposed to face each other across the offset fin in the second direction,
The oil cooler according to claim 9, wherein the second cooling water inflow path and the second cooling water outflow path are disposed to face each other across the offset fin in the third direction.
The rib (75) for suppressing a short circuit of the flow of the cooling water between the first cooling water inflow path and the second cooling water inflow path is formed between the first cooling water inflow path and the second cooling water inflow path. The oil cooler according to any one of the preceding claims.
The oil cooler according to any one of claims 7 to 11, wherein a flow direction of the cooling water from the second cooling water inflow path to the second cooling water outflow path is opposite to a flow direction of the oil.