KR102383362B1 - System for controlling temperature of transmission fluid - Google Patents

Abstract

The present invention relates to a transmission oil temperature control system, and the main object of the present invention is to provide a transmission oil temperature control system capable of always maintaining and controlling the temperature of ATF (transmission oil) at an appropriate temperature regardless of vehicle load conditions, etc. . In order to achieve the above object, the transmission oil (ATF) and the engine coolant pass through, the ATF warmer is made of heat exchange between the transmission oil and the engine coolant; an oil cooler that cools the transmission oil while passing the transmission oil that moves to the transmission side after passing through the ATF warmer; a bypass line for bypassing the transmission oil that has passed through the ATF warmer so that it does not pass through the oil cooler; a first valve installed to open and close the flow path of the coolant line connected to the ATF warmer; a second valve installed to selectively open and close the flow path of the bypass line and the flow path of the ATF circulation line between the oil cooler and the transmission side; a first temperature sensor detecting a temperature of the transmission oil; and a control unit for controlling driving of the first valve and the second valve according to the temperature of the transmission oil detected by the first temperature sensor.

Description

Transmission fluid temperature control system

The present invention relates to a transmission oil temperature control system, and more particularly, to a system for maintaining and controlling the temperature of transmission oil at an appropriate level.

As is known, an automatic transmission is a transmission in which a vehicle shift is automatically performed according to a vehicle speed without a driver's clutch operation or shift operation required in a manual transmission.

In such an automatic transmission, transmission oil (Automatic Transmission Fluid, hereinafter referred to as 'ATF') is used to smoothly transmit power from a vehicle driving source such as an engine or a motor to a drive shaft.

ATF is used as a working fluid to transmit power in a torque converter of an automatic transmission, and is used as a working fluid for clutches, brakes, and valve bodies, as well as for lubrication and cooling of parts such as gears and bearings.

ATF is designed to improve the durability of the clutch plate when the clutch is interrupted by adding a friction agent having an appropriate coefficient of friction to itself, but due to this, heat generation due to friction occurs during torque transmission and the temperature may rise gradually. .

In addition, the temperature of the ATF may rise during component lubrication and cooling.

Therefore, in order to lower the temperature of the ATF, an oil cooler (mainly air-cooled) that cools the ATF is installed near the radiator of the vehicle, and the ATF (transmission oil) is circulated through the oil cooler, thereby preventing the temperature rise of the ATF.

On the other hand, when the temperature of the ATF is low during low-temperature or cold operation, the working efficiency of the ATF is lowered. In particular, when the temperature of the ATF is low, the fluid viscosity increases and friction increases in the parts using the ATF, thereby lowering the fuel efficiency of the vehicle. This happens.

The above-described oil cooler only cools the ATF, and does not have a function for warming up the ATF if necessary, that is, a function for raising the temperature of the ATF under low temperature or cold operating conditions.

Accordingly, an ATF warmer that raises the temperature of the ATF is known.

The ATF warmer is a device whose main purpose is to reduce friction and improve vehicle fuel efficiency by heating the ATF. When the temperature of the ATF is low, the ATF warmer heats the ATF to lower the fluid viscosity to induce friction reduction, thereby improving vehicle fuel efficiency.

For this purpose, an ATF warmer that heats the ATF using engine coolant as a heat source, that is, an ATF warmer that increases the temperature of the ATF through heat exchange between the ATF and high-temperature engine coolant is known.

The ATF warmer is provided as a kind of heat exchanger that allows heat exchange between the ATF and the engine coolant passing through the ATF and the engine coolant, respectively, while passing through the ATF warmer.

1 is a perspective view showing an example of an ATF warmer according to the prior art.

As shown, the ATF warmer 30 is provided with coolant inlet and outlet so that the engine coolant is introduced and then passed through the inside and discharged again to the outside, and after the ATF is introduced, it passes through the inside and is discharged to the outside again. ATF inlet and outlet are provided for this.

In addition, pipes 31 , 32 , 33 , 34 through which cooling water and ATF flow are connected to each inlet and outlet.

2 is a view showing the engine coolant and ATF circulation system, the engine cooling system including the radiator 11, the water pump 12, and the thermostat 13 and the heater core 14 for vehicle air conditioning, the transmission ( 20), it shows the connection relationship between the ATF warmers 30.

As shown, the engine coolant is circulated along the coolant circulation line 14 by the water pump 12, and the coolant that has passed through the engine 10 is the heater core 15 and the thermostat 13, the water pump ( 12) to be circulated back to the engine 10.

In addition, when the internal flow path on the radiator side is opened in the thermostat 13 , some of the coolant from the engine 10 passes through the radiator 11 , and after being cooled in the radiator 11 , it is circulated back to the engine 10 . has been

In addition, the ATF from the transmission 20 passes through the ATF warmer 30 and then circulates back to the transmission side, and the engine coolant from the engine 10 passes through the ATF warmer 30 and then circulates back to the engine side, ATF In the warmer 30, heat exchange is performed between the ATF and the engine coolant.

In this configuration, the ATF warmer 30 warms up the ATF using the engine coolant heated by the engine 10 at the time of cold start, but after the ATF temperature rises to a certain extent, the ATF temperature rises by the engine coolant This can be suppressed.

That is, if the temperature of the ATF is lower than the temperature of the engine coolant, the engine coolant acts as a heating during heat exchange and increases the temperature of the ATF. As a result, the temperature rise of the ATF can be suppressed.

Examples of prior art documents related to the ATF warmer include Patent Publication No. 10-2013-0065049 (Jan. 19, 2013), and Patent Publication No. 10-2016-0112403 (Sep. 28, 2016).

However, since the conventional ATF warmer is a device for increasing the temperature of ATF (transmission oil) using engine coolant, it has a problem in that the temperature of the ATF may be excessively increased according to the load condition of the vehicle.

That is, if the engine coolant temperature rises under high load conditions, the cooling action by the engine coolant weakens and the ATF temperature may rise excessively. there is.

This adversely affects the durability and safety of the transmission.

Accordingly, the present invention was created to solve the above problems, and it is an object of the present invention to provide a transmission oil temperature control system capable of always controlling the temperature of ATF (transmission oil) to an appropriate temperature regardless of vehicle load conditions, etc. There is this.

In order to achieve the above object, according to an embodiment of the present invention, transmission oil (ATF: Automatic Transmission Fluid) and the engine coolant pass through, the ATF warmer that heat exchange between the transmission oil and the engine coolant; an oil cooler cooling the transmission oil while passing the transmission oil moving to the transmission side after passing through the ATF warmer; a bypass line for bypassing the transmission oil that has passed through the ATF warmer to the transmission side so as not to pass through the oil cooler; a first valve installed to open and close a flow path of a coolant line connected to the ATF warmer, the first valve being opened and closed to selectively flow engine coolant to the ATF warmer; It is installed to selectively open and close the flow path of the bypass line and the flow path of the ATF circulation line between the oil cooler and the transmission side, and is operated to bypass the transmission oil through the oil cooler or without passing through the oil cooler a second valve; a first temperature sensor detecting a temperature of the transmission oil; and a control unit for controlling driving of the first valve and the second valve according to the temperature of the transmission oil detected by the first temperature sensor.

Accordingly, according to the transmission oil temperature control system according to the present invention, by controlling the ATF flow path according to the ATF temperature, it is possible to maintain and control the ATF temperature using the ATF warmer and the oil cooler, and the ATF temperature can be controlled regardless of the load condition of the vehicle. There is always the effect of maintaining and controlling the appropriate temperature.

1 is a perspective view showing an example of an ATF warmer according to the prior art.
2 is a view showing an engine coolant and ATF circulation system according to the prior art.
3 is a diagram showing the configuration of a transmission oil temperature control system according to an embodiment of the present invention.
4 is a block diagram illustrating a temperature sensor, a control unit, and a valve in a transmission oil temperature control system according to an embodiment of the present invention.
5 is a perspective view illustrating an oil cooler of a transmission oil temperature control system according to an embodiment of the present invention.
6 is a flowchart illustrating a transmission oil temperature control process according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those of ordinary skill in the art can easily carry out the embodiments of the present invention. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms.

Throughout the specification, when a part "includes" a certain element, it means that other elements may be further included, rather than excluding other elements, unless otherwise stated.

The main object of the present invention is to provide a transmission oil temperature control system capable of always maintaining and controlling the temperature of ATF (transmission oil) at an appropriate temperature regardless of vehicle load conditions.

To this end, a temperature control system using an ATF warmer and an oil cooler in combination is disclosed.

In the following description, the transmission oil will be referred to as ATF.

3 is a diagram showing the configuration of a transmission oil temperature control system according to an embodiment of the present invention, and FIG. 4 is a temperature sensor 61 and 62 and a control unit 70 in the transmission oil temperature control system according to the embodiment of the present invention. , a block diagram showing the valves 81 and 82 .

As shown, the transmission oil temperature control system according to an embodiment of the present invention includes an ATF warmer 30, an oil cooler 40, a bypass line 56, first and second temperature sensors 61 and 62, It is configured to include a control unit 70, first and second valves (81, 82).

3 shows the engine coolant and ATF circulation system, and more specifically, shows the configuration of the engine cooling system together with the configuration of the oil temperature control system according to the embodiment of the present invention.

In addition, among the configuration of the oil temperature control system according to the embodiment of the present invention, the configuration not shown in FIG. 3 , that is, the first and second temperature sensors 61 and 62 and the control unit 70 are shown in the block diagram of FIG. indicated.

In FIG. 3 , there is no difference compared to the known configurations in the configuration of the engine cooling system and the circulation path of the engine coolant, and the engine cooling system emits heat from the water pump 12 for circulating the engine coolant and the engine coolant in an air-cooled manner. and a radiator 11 for cooling the engine coolant as possible, and a thermostat 13 for controlling a flow path of the engine coolant so that the engine coolant selectively passes through the radiator 11 .

In addition, the heater core 15 for vehicle air conditioning may be equally installed in the engine coolant circulation line 14 through which the engine coolant is circulated, and there is no difference compared with the known configuration.

In the illustrated engine coolant circulation system, when the internal flow path on the radiator side is closed in the thermostat 13 , the coolant is heated in the engine 10 and then the heater core 15 , the water pump 12 , and the thermostat 13 . It is circulated back to the engine 10 along the path through the

In addition, when the internal flow path on the side of the radiator is opened in the thermostat 13, some of the high-temperature coolant from the engine 10 passes through the radiator 11, and air from the radiator 11 (which may be running wind) ) and then circulated back to the engine 10 along a path via the thermostat 13 and the water pump 12 .

At the same time, the high-temperature coolant from the engine 10 passes through the ATF warmer 30 and then circulates back to the engine 10 along a path passing through the thermostat 13 and the water pump 12, at this time the transmission ( The ATF (transmission oil) from 20) is also passed through the ATF warmer 30 . As is known, the ATF warmer 30 heats the ATF by heat exchange between the ATF and engine coolant.

On the other hand, the oil temperature control system according to the present invention further includes an oil cooler 40 for cooling the ATF, and after the ATF from the transmission 20 goes through the ATF warmer 30, an oil cooler 40 is added. is allowed to pass through.

The oil cooler 40 may be provided as an air-cooled cooler similar to the radiator 11, and the ATF introduced into the oil cooler 40 is cooled by the air passing around the oil cooler and then flows back into the transmission 20. it is made possible

5 is a perspective view illustrating an oil cooler of the transmission oil temperature control system according to an embodiment of the present invention, wherein the oil cooler 40 is air introduced into the radiator 11 from the front end of the vehicle when the vehicle is driving (it may be a driving wind). By, it can be configured to cool the ATF passing through the interior.

At this time, as shown in FIG. 5 , the oil cooler 40 may be disposed around the radiator 11 , more specifically in front of the radiator, and may be installed in a smaller size and volume than the radiator 11 .

Regarding the radiator 11, since it is a known configuration installed at the front end of the vehicle among the configurations of the engine cooling system, a detailed description will be omitted, and the rear of the radiator 11 in the known engine cooling system (based on the vehicle front-rear direction) A radiator fan 11a is installed there, but only a part of the radiator fan 11a is shown in FIG. 5 .

On the other hand, in the transmission oil (ATF) temperature control system of the present invention, the ATF that has passed through the ATF warmer 30 after coming out of the transmission 20 selectively passes through the oil cooler 40 and passes through the oil cooler 40 . One ATF is adapted to flow back into the transmission 20 .

For this, the ATF inlet line 53 through which ATF flows from the transmission 20 to the ATF warmer 30 is connected between the transmission 20 side and the ATF inlet side of the ATF warmer 30, and the ATF warmer 30 ), the first ATF circulation line 54 is connected between the ATF outlet side of the ATF warmer 30 and the ATF inlet side of the oil cooler 40 so that the ATF passed through can be introduced into the oil cooler 40 .

In addition, a second ATF circulation line 55 is connected between the ATF outlet side of the oil cooler 40 and the transmission 20 side.

As a result, the ATF flowing along the first ATF circulation line 54 from the ATF warmer 30 flows into the oil cooler 40 and is cooled by air (which may be a running wind) passing through the surroundings in the oil cooler, Thereafter, the cooled ATF is discharged to the second ATF circulation line 55 to flow back to the transmission 20 side.

In addition, between the first ATF circulation line 54 and the second ATF circulation line 55 , a bypass line 56 for bypassing the ATF that has passed through the ATF warmer 30 and does not pass through the oil cooler 40 . ) is connected.

In addition, a coolant inlet line 51 branched from the coolant circulation line 14 to flow after the high temperature engine coolant is discharged from the engine 10 and connected to the coolant inlet side of the ATF warmer 30 is installed.

In addition, the coolant outlet connected to the coolant circulation line 14 from the coolant outlet side of the ATF warmer 30 so that the engine coolant that has passed through the ATF warmer 30 and has completed heat exchange with the ATF flows back to the coolant circulation line 14 . Line 52 is installed.

At this time, the coolant inlet line 51 may be branched from the coolant circulation line 14 between the engine 10 and the heater core 15 and connected to the coolant inlet side of the ATF warmer 30, and the coolant outlet line 52 is The cooling water outlet side of the ATF warmer 30 may be connected to the cooling water circulation line 14 of the rear end side (downstream side) of the heater core 15 .

In addition, the oil temperature control system according to the present invention includes valves 81 and 82 for determining the flow path of the ATF, and a controller ( 70).

The valves 81 and 82 are electromagnetic valves whose operation is controlled by the controller 70 , and include a first valve 81 for selectively controlling the inlet and outlet of engine coolant to and from the ATF warmer 30 , and the ATF warmer 30 . ) includes a second valve 82 installed in the bypass line 56 to control the ATF discharged from the oil cooler 40 to selectively pass through.

The first valve 81 may be installed to open and close the flow path of the coolant line connected to the ATF warmer, and the second valve 82 may open/close the flow path of the bypass line 56 , in particular, the bypass line 56 . ) and the oil cooler side line (55a) may be selectively connected to the transmission side line (55b) and installed to switch the connection.

Referring to FIG. 3 , the first valve 81 is branched from the engine coolant circulation line 14 connected from the coolant outlet of the engine 10 to the coolant inlet of the heater core 15 and the ATF warmer 30 is installed. You can see it installed in the coolant line.
Here, the first valve 81 is a coolant inlet line 51 branched from the coolant circulation line 14 and connected to the coolant inlet side of the ATF warmer 30 among the coolant lines in which the ATF warmer 30 is installed. , or may be installed in the coolant outlet line 52 connected to the coolant circulation line 14 from the coolant outlet side of the ATF warmer 30 .

In the embodiment of FIG. 3 , the first valve 81 is installed in the coolant inlet line 51 .

In addition, the second valve 82 may be a 3-way valve installed at the junction of the outlet end of the bypass line 56 and the second ATF circulation line 55 .

When the first valve 81 is closed, the high-temperature engine coolant from the engine 10 does not flow through the ATF warmer 30, and at this time, the engine coolant flows through only the heater core 15 in the engine 10. It flows into the engine 10 again through the rear thermostat 13 and the water pump 12 .

On the other hand, when the first valve 81 is opened, the high-temperature engine coolant from the engine 10 flows through the ATF warmer 30, whereby heat exchange between the ATF and the engine coolant is performed in the ATF warmer 30. will be done

At this time, under the condition that the ATF temperature is lower than the engine coolant temperature, the ATF may be heated by the engine coolant in the ATF warmer 30 , and conversely, under the condition that the ATF temperature is higher than the engine coolant temperature, the ATF warmer 30 uses the engine coolant The ATF may be cooled.

In addition, the second valve 82 includes a line 55b connected to the transmission 20 side of the second ATF circulation line 55 , a line 55a connected to the oil cooler 40 side, and a bypass line 56 , respectively. It has three ports to be connected, and in the following description, the port to which the bypass line 56 is connected is the first port 83a , and the port to which the transmission side line 55a is connected among the second ATF circulation line 55 is the second A port to which the oil cooler side line 55b is connected among the port 83b and the second ATF circulation line 55 will be referred to as a third port 83c.

The second valve 82 has an internal flow path to which the bypass line 56 is connected and the first port 83a, and an internal flow path to which the transmission-side line 55a of the second ATF circulation line 55 is connected. and when the second port 83b is opened and the internal flow path to which the oil cooler side line 55b of the second ATF circulation line 55 is connected and the third port 83c are closed, the bypass line 56 This is opened and the oil cooler-side line 55b is in a blocked state, and the bypass line 56 and the transmission-side line 55a of the second ATF circulation line 55 are connected to each other.

In this case, the ATF that has passed through the ATF warmer 30 after coming out from the transmission 20 through the ATF inlet line 53 goes to the transmission 20 through the first ATF circulation line 54 and the bypass line 56 . can be reintroduced.

In addition, the second valve 82 includes an internal flow path and a second port 83b to which the transmission-side line 55a of the second ATF circulation line 55 is connected, and the oil in the second ATF circulation line 55 . When the internal flow path and the third port 83c to which the cooler side line 55b is connected are opened and the internal flow path and the first port 83a to which the bypass line 56 are connected are closed, the bypass line ( 56) is cut off and the oil cooler side line 55b is in an open state, so that the oil cooler side line 55b of the second ATF circulation line 55 and the transmission side line 55a of the second ATF circulation line 55 are closed. ) is connected.

In this case, the ATF that has passed through the ATF warmer 30 after coming out of the transmission 20 through the ATF inlet line 53 is the first ATF circulation line 54 , the oil cooler 40 , and the second ATF circulation line 55 . ) and may be introduced back to the transmission 20 side.

And, the oil temperature control system according to the embodiment of the present invention further includes a first temperature sensor 61 for detecting the temperature of the transmission oil, that is, the ATF, and a second temperature sensor 62 for detecting the temperature of the engine coolant. do.

Here, although not shown in detail in the drawings, the first temperature sensor 61 may be installed to detect the temperature of the ATF before it flows into the ATF warmer 30, for example, the transmission 20 side or the ATF inlet line ( 53) can be installed.

In addition, the second temperature sensor 62 may be a known water temperature sensor for detecting the engine coolant temperature.

Alternatively, it may be a separate temperature sensor installed to detect the temperature of the engine coolant before flowing into the ATF warmer 30 , and for example, the second temperature sensor 62 includes the engine 10 and the heater core 15 . It may be installed in the cooling water circulation line 14 between them, or it may be installed in the cooling water inlet line 51 branched from the cooling water circulation line 14 .

Next, an operating state of the oil temperature control system and an oil temperature control process according to an embodiment of the present invention will be described with reference to FIG. 6 .

6 is a flowchart illustrating an oil temperature control process according to an embodiment of the present invention.

In the present invention, when the temperature of the transmission oil, that is, the temperature of the ATF is below the reference temperature preset in the control unit 70, the ATF is circulated to pass only the ATF warmer 30 in the same way as before, and the temperature of the ATF is higher than the reference temperature. When in the state, the ATF is circulated to pass through both the water-cooled ATF warmer 30 and the air-cooled oil cooler 40 .

The ATF circulation path and flow control may be performed by the control unit 70 controlling the driving of the first valve 81 and the second valve 82 , and the control unit 70 may control the first temperature sensor 61 and the second valve 82 . 2 A control signal for controlling the operation of the first valve 81 and the second valve 82 is output according to the sensor value of the temperature sensor 62 , that is, the ATF and engine coolant temperature detection values.

The reference temperature can be set to the maximum temperature at which fuel efficiency can be improved by maintaining the viscosity of the ATF at an appropriate level, and when the ATF temperature is higher than the reference temperature, the control unit 70 determines that the ATF is in an overtemperature state. .

First, after the vehicle is started, that is, after the ignition key is turned on, the temperature control system of the present invention is automatically turned on (S11), and then the control unit 70 operates the first valve 81 Outputs a control signal for opening.

Accordingly, the first valve 81 is opened according to the control signal of the control unit 70 (S12), and accordingly, some of the high-temperature engine coolant discharged from the engine 10 is transferred to the coolant inlet line 51 and the ATF warmer 30 ), the coolant is circulated through the outlet line 52 .

In addition, the control unit 70 receives the detection signals of the first temperature sensor 61 and the second temperature sensor 62 , and at this time, the control unit 70 receives the ATF temperature, which is the detection value of the first temperature sensor 61 . It is compared with a preset reference temperature (S13).

Here, when the ATF temperature detected by the first temperature sensor 61 is in an overtemperature state higher than the reference temperature, the control unit 70 is a control signal for opening the ATF flow path passing through the oil cooler 40 , that is, the ATF A control signal for setting the flow path of the ATF to pass through the oil cooler 40 is output (S14).

That is, the control unit 70 closes the bypass line 56 and opens the oil cooler side line 55b of the second ATF circulation line 55 and the transmission side line 55a of the second ATF circulation line 55 . It is designed to output a control signal for cycle.

At this time, in the second valve 82 according to the control signal of the controller 70 , the internal flow path and the second port 83b to which the transmission-side line 55a of the second ATF circulation line 55 is connected, and the second The internal flow path and the third port 83c to which the oil cooler side line 55b of the ATF circulation line 55 are connected are opened, while the internal flow path and the first port 83a to which the bypass line 56 is connected. ) is closed.

As a result, the oil cooler side line 55b of the second ATF circulation line 55 and the transmission side line 55a of the second ATF circulation line 55 are connected, and the oil cooler side line 55b is opened and the The pass line 56 is in a blocked state, and accordingly, the ATF from the transmission 20 is the ATF inlet line 53 , the ATF warmer 30 , the first ATF circulation line 54 , the oil cooler 40 , It flows along the oil cooler side line 55b and the transmission side line 55a of the second ATF circulation line 55 .

Accordingly, the ATF is further cooled by air cooling while passing through the oil cooler 40 after heat exchange with the engine coolant is made in the ATF warmer 30 , and then the cooled ATF is introduced into the transmission 20 again.

In this process, the ATF is first cooled from a high-temperature and over-temperature state to a medium temperature by the engine coolant in the ATF warmer 30, and thereafter by the air passing through the surroundings in the oil cooler 40, the temperature will be lower than the reference temperature from the medium temperature. secondary cooling until

In this way, in the overtemperature condition where the ATF temperature is higher than the reference temperature, a path is set so that the ATF circulates through the transmission 20, ATF warmer 30, oil cooler 40, and transmission 20, and the ATF temperature is below the reference temperature. After the ATF primary cooling in the ATF warmer 30 until the ATF secondary cooling in the oil cooler 40 is continuously made.

In addition, when the ATF temperature detected by the first temperature sensor 61 in step S13 is lower than the reference temperature or is lower than the reference temperature after step S14, the control unit 70 passes through the bypass line 56 A control signal for opening the ATF flow path, that is, a control signal for opening the bypass line 56 is output (S15).

That is, the control unit 70 closes the oil cooler-side line 55b of the second ATF circulation line 55 and opens the bypass line 56 and the transmission-side line 55a of the second ATF circulation line 55 . It is designed to output a control signal for cycle.

At this time, in the second valve 82 according to the control signal of the controller 70 , the internal flow path and the first port 83a to which the bypass line 56 is connected, and the transmission side of the second ATF circulation line 55 . The internal flow path to which the line 55a is connected and the second port 83b are opened, and at the same time, the internal flow path and the third port 83c to which the oil cooler side line 55b of the second ATF circulation line 55 is connected. ) is closed.

As a result, the bypass line 56 and the transmission side line 55a of the second ATF circulation line 55 are connected, and the bypass line 56 is open and the oil cooler side line 55b is blocked. Accordingly, the ATF from the transmission 20 is the ATF inlet line 53 , the ATF warmer 30 , the first ATF circulation line 54 , the bypass line 56 , and the second ATF circulation line 55 . It flows through the transmission side line 55a.

As a result, a flow path for bypassing the ATF is set so that it does not pass through the oil cooler 40 , so that the ATF is only heat-exchanged with the engine coolant in the ATF warmer 30 and then flows back into the transmission 20 .

Then, the control unit 70 compares the ATF temperature detected by the first temperature sensor 61 with the coolant temperature detected by the second temperature sensor 62 (S16), wherein the ATF temperature is lower than the engine coolant temperature In the condition, the bypass line 56 is maintained in an open state (moved to 'return' in FIG. 6) to allow heat exchange between the ATF and the engine coolant in the ATF warmer 30, and through this, the ATF is transferred to the engine coolant. to be heated by

If the ATF temperature is lower than the engine coolant temperature and satisfies the system-on condition of step S11 and does not satisfy the condition of step S13, the open state of the bypass line 56 is continuously maintained, but if the condition of step S13 is satisfied, S14 go to step

On the other hand, when the ATF temperature is equal to or higher than the cooling water temperature in step S16, a control signal for closing the first valve 81 installed in the cooling water inlet line 51 is output (S17).

Accordingly, as the first valve 81 is closed, the engine coolant does not flow to the ATF warmer 30 , and the coolant path passing through the ATF warmer 30 is blocked.

In this case, since the engine coolant does not go through the ATF warmer 30 (the ATF warmer does not circulate in the engine coolant), heat exchange in the ATF warmer 30 , that is, heat exchange between the ATF and the engine coolant, is not performed, and at this time, the ATF temperature is It rises only by the lubrication and cooling action of the ATF in the transmission 20 and the friction of the ATF.

As described above, in the condition where the ATF temperature is higher than the coolant temperature, heat exchange between the engine coolant and the ATF is prevented, thereby solving the problem of the ATF temperature rising under the engine high load condition, and eventually the durability and stability of the transmission due to the excessive increase in the ATF temperature. It is possible to solve the degradation problem.

In this way, according to the transmission oil temperature control system according to the present invention, it is possible to maintain the ATF temperature at an appropriate temperature, it is possible to prevent the ATF temperature from rising to excessive temperature, and it is possible to It is possible to solve the problem of deterioration in durability and stability on the transmission side.

Although the embodiment of the present invention has been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention as defined in the following claims Also included in the scope of the present invention.

10: engine 11: radiator
12: water pump 13: thermostat
14: coolant circulation line 15: heater core
20: transmission 30: ATF warmer
40: oil cooler 51: coolant inlet line
52: coolant outlet line 53: ATF inlet line
54: first ATF circulation line 55: second ATF circulation line
55a: transmission side line 55b: oil cooler side line
56: bypass line 61: first temperature sensor
62: second temperature sensor 70: control unit
81: first valve 82: second valve
83a: first port 83b: second port
83c: 3rd port

Claims (9)

ATF warmer through which automatic transmission fluid (ATF) and engine coolant pass and heat exchange between transmission oil and engine coolant is made;
an oil cooler cooling the transmission oil while passing the transmission oil moving to the transmission side after passing through the ATF warmer;
a bypass line for bypassing the transmission oil that has passed through the ATF warmer to the transmission side so as not to pass through the oil cooler;
a first valve installed to open and close a flow path of a coolant line connected to the ATF warmer, the first valve being opened and closed to selectively flow engine coolant to the ATF warmer;
It is installed to selectively open and close the flow path of the bypass line and the flow path of the ATF circulation line between the oil cooler and the transmission side, and is operated to bypass the transmission oil through the oil cooler or without passing through the oil cooler a second valve;
a first temperature sensor detecting a temperature of the transmission oil; and
And a control unit for controlling the driving of the first valve and the second valve according to the temperature of the transmission oil detected by the first temperature sensor,
The transmission oil temperature control system, characterized in that the first valve is branched from an engine coolant circulation line connected from the coolant outlet of the engine to the coolant inlet of the heater core and installed in the coolant line in which the ATF warmer is installed.
The method according to claim 1,
The oil cooler is an air-cooled cooler installed around a vehicle radiator that cools the engine coolant, so that the transmission oil passing through the inside is cooled by the air flowing into the radiator.
The method according to claim 1,
A coolant inlet line branched from the engine coolant circulation line through which the engine coolant circulates is a coolant line connected to the ATF warmer and is connected to the coolant inlet side of the ATF warmer,
The coolant outlet line through which the engine coolant that has passed through the ATF warmer is discharged is connected to the engine coolant circulation line from the coolant outlet side of the ATF warmer,
The transmission oil temperature control system, characterized in that the first valve is installed in the coolant inlet line or the coolant outlet line.
The method according to claim 1,
An ATF inlet line is connected between the transmission side and the ATF inlet side of the ATF warmer so that transmission oil can flow from the transmission side to the ATF warmer,
A first ATF circulation line is connected between the ATF outlet side of the ATF warmer and the ATF inlet side of the oil cooler so that the transmission oil that has passed through the ATF warmer can flow into the oil cooler,
A second ATF circulation line is connected between the ATF outlet side of the oil cooler and the transmission side so that the transmission oil that has passed through the oil cooler can flow into the transmission side,
Transmission oil temperature control system, characterized in that the bypass line is connected between the first ATF circulation line and the second ATF circulation line.
5. The method according to claim 4,
The second valve is
It is installed at the joint point of the bypass line and the second ATF circulation line,
By opening one of the flow path of the bypass line and the flow path of the oil cooler side line connected to the ATF outlet side of the oil cooler among the second ATF circulation lines,
Transmission oil temperature control system, characterized in that the one open flow path is a 3-way valve to be connected to a transmission side line connected to the transmission side of the second ATF circulation line.
The method according to claim 1,
The control unit is
When the temperature of the transmission oil detected by the first temperature sensor is higher than a preset reference temperature, the second valve blocks the flow path of the bypass line and opens the flow path of the ATF circulation line between the oil cooler and the transmission side. The transmission oil temperature control system, characterized in that by controlling the drive of the transmission oil to pass through the ATF warmer and the oil cooler in turn.
The method according to claim 1,
The control unit is
When the temperature of the transmission oil detected by the first temperature sensor is below the preset reference temperature, the second valve opens the flow path of the bypass line and blocks the flow path of the ATF circulation line between the oil cooler and the transmission side. Transmission oil temperature control system, characterized in that by controlling the drive, the transmission oil that has passed through the ATF warmer is bypassed along the bypass line so that it does not pass through the oil cooler.
The method according to claim 1,
Further comprising a second temperature sensor for detecting the temperature of the engine coolant,
The control unit is
Transmission according to the temperature of the transmission oil detected by the first temperature sensor and the temperature of the engine coolant detected by the second temperature sensor to control the operation of the first valve and the second valve Oil temperature control system.
9. The method of claim 8,
The control unit is
When the temperature of the transmission oil detected by the first temperature sensor is below a preset reference temperature and the temperature of the transmission oil is equal to or greater than the temperature of the engine coolant detected by the second temperature sensor, the first valve is closed , Transmission oil temperature control system, characterized in that the engine coolant does not flow through the ATF warmer.

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