KR102372104B1 - Method and apparatus for diagnosing obstacle of thermostat - Google Patents

Abstract

Disclosed are a method and apparatus for diagnosing a failure of a water temperature controller. A method for diagnosing a failure of a water temperature controller according to an aspect of the present invention comprises the steps of: a controller comparing a model temperature and an actual temperature of cooling water with a preset temperature to diagnose a failure of the water temperature controller; and controlling, by the controller, a valve angle of the water temperature controller, and rediagnosing the failure of the water temperature controller based on a temperature change value of the coolant according to the valve angle control.

Description

Method and device for diagnosing water temperature controller failure

The present invention relates to a method and apparatus for diagnosing a failure of a water temperature controller, and more particularly, to a water temperature controller The present invention relates to a method and apparatus for diagnosing a failure of a water temperature controller by changing the rotational opening angle of the inside and diagnosing the failure of the water temperature controller based on the amount of change in the coolant temperature according to the change in the opening angle.

The cooling system is used as a means to prevent overheating of the engine, to protect the engine by maintaining the engine at an appropriate temperature, and to improve combustion efficiency.

Although the temperature of the combustion gases in the cylinder reaches about 2000 degrees Celsius, a significant amount of this heat is absorbed by the cylinder, cylinder head, piston, etc. If the temperature of these parts rises excessively, the cylinder is deformed or the oil film on the cylinder wall is destroyed, resulting in poor lubrication and, in severe cases, damage to the engine.

In addition, the combustion state is also deteriorated, which causes knocking or early ignition, which is one factor that reduces the output of the engine. Conversely, if it is cooled too much, the amount of heat generated by combustion that is lost through cooling increases, which lowers the thermal efficiency of the engine and increases fuel consumption.

As a method of cooling the engine, there are an air cooling type in which the outside of the engine is directly cooled using outside air and a water cooling type in which cooling is performed by purifying the coolant inside the engine.

The water cooling type draws cooling water to the cylinder block and the water jacket of the cylinder head with a water pump and circulates it for heat exchange. The heated cooling water is sent to the radiator to lower the temperature by the atmosphere and then circulates again by the water pump. have

In such a water-cooled engine, a water pump circulates the coolant, but a water temperature controller is installed in the cooling system to cool the cylinder and prevent the coolant from flowing to the radiator when the temperature of the coolant does not reach a constant temperature.

Furthermore, conventionally, the water temperature controller has been diagnosed as a phenomenon in which a difference between the actual coolant temperature and the modeled coolant temperature occurs by using coolant temperature modeling to diagnose whether the water temperature controller has a failure.

However, there are many variables (eg, driving wind, engine calorific value, etc.) in the process of modeling the coolant temperature, so there is a limit to accurately modeling.

For this reason, there has always been a possibility of a misdiagnosis of the water temperature controller (ie, a normal product is mistakenly recognized as a defective product). In particular, due to the strengthening of regulations related to self-diagnosis of vehicles, it was required to diagnose faulty parts in a specific mode (eg, exhaust gas measurement mode), so it was necessary to keep the coolant temperature modeling close to the actual coolant temperature. There is a problem that increases the likelihood.

The background technology of the present invention is disclosed in 'a method for preventing thermostat misdiagnosis of a vehicle' of Republic of Korea Patent Publication No. 10-1939171 (2019.01.16 announcement).

The present invention has been devised to improve the above problems, and an object of the present invention is not to use only the model temperature and actual temperature of the cooling water, but a water temperature controller To provide a method and apparatus for diagnosing a malfunction of a water temperature controller, which can prevent erroneous diagnosis by directly checking whether the coolant temperature is substantially changed by changing the rotational opening angle of the inside, thereby increasing the robustness of the water temperature controller for fault diagnosis.

The problem to be solved by the present invention is not limited to the problem(s) mentioned above, and another problem(s) not mentioned will be clearly understood by those skilled in the art from the following description.

A method for diagnosing a failure of a water temperature controller according to an aspect of the present invention comprises the steps of: a controller comparing a model temperature and an actual temperature of cooling water with a preset temperature to diagnose a failure of the water temperature controller; and controlling, by the controller, a valve angle of the water temperature controller, and rediagnosing the failure of the water temperature controller based on a temperature change value of the coolant according to the valve angle control.

In the present invention, the step of diagnosing the failure of the water temperature controller may include: comparing, by the controller, the model temperature of the coolant with a preset critical temperature; The method may include comparing the temperature with a preset diagnosis temperature, and when the actual temperature is less than the diagnosis temperature, the control unit diagnosing that the water temperature controller is malfunctioning.

In the present invention, the step of rediagnosing the failure of the water temperature controller includes: the controller changing the valve angle to a flow stop section to increase the coolant temperature; When a preset time elapses, the controller opens the valve lowering the cooling water temperature, and the controller rediagnosing the failure of the water temperature controller based on a temperature rise value due to an increase in the cooling water temperature and a temperature decrease value due to a decrease in the cooling water temperature. .

In the present invention, the step of rediagnosing the failure of the water temperature controller based on the temperature rise value due to the increase in the cooling water temperature and the temperature decrease value due to the decrease in the cooling water temperature includes the controller setting the temperature rise value to a preset value. Comparing with one reference value, when the temperature rise value exceeds the first reference value, comparing the temperature drop value with a preset second reference value, when the temperature drop value exceeds the second reference value and determining that the water temperature controller is normal, and determining that the water temperature controller is malfunctioning when the second reference value is not exceeded.

In the present invention, when the temperature rise value does not exceed the first reference value, it may be determined that the water temperature controller is malfunctioning.

In the present invention, the step of increasing the coolant temperature by changing the valve angle to a flow stop section includes: a first coolant passage through which the coolant distributed to the heater core flows through the valve, a second coolant passage through which the coolant distributed to the radiator flows, and an ATF (Automatic transmission fluid) It can be changed to a flow stop section that blocks the third coolant flow passage through which the coolant distributed.

In the present invention, in the step of lowering the coolant temperature by opening the valve, the valve may be controlled so that the opening rate of the second coolant flow passage through which the coolant distributed to the radiator flows is maximized.

According to another aspect of the present invention, there is provided a method for diagnosing a failure of a water temperature controller, comprising the steps of: a controller controlling a valve angle of the water temperature controller; including the steps of

In the present invention, the step of controlling the valve angle of the water temperature controller includes the step of, by the controller, changing the valve angle to a flow stop section to increase the coolant temperature. When a predetermined time elapses, the controller opens the valve and lowering the coolant temperature.

In the present invention, the step of increasing the coolant temperature by changing the valve angle to the flow stop section includes a first coolant flow path through which coolant distributed to the heater core flows, a second coolant flow path through which coolant distributed to the radiator 11 flows, and ATF It may be characterized in that the valve is controlled as a flow stop section that blocks the third coolant flow path through which coolant distributed as an automatic transmission fluid flows.

In the present invention, the step of lowering the coolant temperature by opening the valve may include controlling the valve so that the opening rate of the second coolant flow passage through which the coolant distributed to the radiator flows is maximized.

In the present invention, the step of diagnosing the failure of the water temperature controller may include: comparing, by the controller, a temperature rise value caused by the rise in the coolant temperature with a preset first reference value, wherein the temperature rise value exceeds the first reference value case, comparing, by the control unit, a temperature decrease value due to the decrease in the cooling water temperature with a preset second reference value, and if the temperature decrease value exceeds the second reference value, determining that the water temperature controller is normal, and the If the second reference value is not exceeded, determining that the water temperature controller is defective.

In the present invention, when the temperature rise value does not exceed the first reference value, it may be determined that the water temperature controller is malfunctioning.

According to another aspect of the present invention, there is provided an apparatus for diagnosing a failure of a water temperature controller, a water temperature controller installed at a predetermined position of a coolant flow path connecting an engine and a radiator to control a circulation direction and flow rate of coolant, and a temperature for measuring the temperature of the coolant a sensor and a controller for variably controlling the coolant temperature by controlling the water temperature controller, wherein the controller controls a valve angle of the water temperature controller, and based on a temperature change value of the coolant according to the valve angle control Diagnose the fault.

In the present invention, the control unit increases the coolant temperature by changing the valve angle to a flow stop section, opens the valve when a predetermined time has elapsed, and lowers the coolant temperature, and the temperature caused by the increase in the coolant temperature The failure of the water temperature controller may be diagnosed based on an increase value and a temperature decrease value due to a decrease in the cooling water temperature.

In the present invention, in order to increase the temperature of the cooling water, the control unit divides the valve into a first cooling water flow path through which the cooling water distributed to the heater core flows, a second cooling water flow path through which the cooling water distributed to the radiator flows, and an automatic transmission fluid (ATF). It can be controlled as a flow stop section that blocks the third cooling water flow path through which the distributed cooling water flows.

In the present invention, the controller may control the valve to maximize the opening rate of the second cooling water passage through which the cooling water distributed to the radiator flows in order to lower the temperature of the cooling water.

In the present invention, the controller compares the temperature rise value with a preset first reference value, and compares the temperature drop value with a preset second reference value when the temperature rise value exceeds the first reference value as a result of the comparison And, as a result of the comparison, when the temperature drop value exceeds the second reference value, it is determined that the water temperature controller is normal, and when it does not exceed the second reference value, it can be determined that the water temperature controller is malfunctioning.

In the present invention, when the temperature rise value does not exceed the first reference value, the controller may determine that the water temperature controller is malfunctioning.

In the present invention, the control unit diagnoses the failure of the water temperature controller by comparing the model temperature of the coolant and the actual temperature measured by the temperature sensor with a preset temperature, A valve angle of the water temperature controller may be controlled, and the failure of the water temperature controller may be rediagnosed based on a temperature change value of the coolant according to the valve angle control.

In the present invention, the control unit compares the model temperature of the cooling water with a preset critical temperature, compares the actual temperature of the cooling water with a preset diagnosis temperature when the model temperature exceeds the threshold temperature, and the comparison result is the When the actual temperature is less than the diagnosis temperature, the water temperature controller may be diagnosed as malfunctioning.

The method and apparatus for diagnosing a failure of a water temperature controller according to an embodiment of the present invention does not use only the model temperature and the actual temperature of the coolant, but also the water temperature controller By changing the rotational opening angle of the inside, it is possible to directly check whether the temperature actually changes, thereby increasing the robustness to the fault diagnosis of the water temperature controller and preventing erroneous diagnosis.

On the other hand, the effects of the present invention are not limited to the above-mentioned effects, and various effects may be included within the range obvious to those skilled in the art from the description below.

1 is a diagram schematically showing a cooling device according to an embodiment of the present invention.
2 is a partial perspective view of a water temperature controller according to an embodiment of the present invention.
3 is a block diagram schematically showing the configuration of an apparatus for diagnosing a failure of a water temperature controller according to an embodiment of the present invention.
4 is a view for explaining a cooling water flow path according to an embodiment of the present invention.
5 is a flowchart illustrating a method for diagnosing a failure of a water temperature controller according to an embodiment of the present invention.

Hereinafter, a method and apparatus for diagnosing a failure of a water temperature controller according to an embodiment of the present invention will be described with reference to the accompanying drawings. In this process, the thickness of the lines or the size of the components shown in the drawings may be exaggerated for clarity and convenience of explanation.

In addition, the terms to be described later are terms defined in consideration of functions in the present invention, which may vary according to the intention or custom of the user or operator. Therefore, definitions of these terms should be made based on the content throughout this specification.

Further, implementations described herein may be implemented as, for example, a method or process, an apparatus, a software program, a data stream, or a signal. Although discussed only in the context of a single form of implementation (eg, discussed only as a method), implementations of the discussed features may also be implemented in other forms (eg, as an apparatus or program). The apparatus may be implemented in suitable hardware, software and firmware, and the like. A method may be implemented in an apparatus such as, for example, a processor, which generally refers to a computer, a microprocessor, a processing device, including an integrated circuit or programmable logic device, and the like. Processors also include communication devices such as computers, cell phones, portable/personal digital assistants (“PDA”) and other devices that facilitate communication of information between end-users.

1 is a diagram schematically showing a cooling device according to an embodiment of the present invention.

Referring to FIG. 1 , a cooling device according to an embodiment of the present invention includes an engine 10 , a radiator 11 , a coolant pump 12 , a coolant flow path 13 , a bypass flow path 14 , and a water temperature controller 120 . , a cooling fan motor 16 , a temperature sensor 200 and a control unit 100 .

The engine 10 and the radiator 11 are connected through the coolant flow passage 13 , and the coolant pump 12 and the water temperature controller 120 are installed at a predetermined position of the coolant flow passage 13 .

The radiator 11 expands the contact area between the coolant and the atmosphere through the core to dissipate the heat absorbed in the coolant, and according to the coolant temperature condition and the driving condition of the vehicle, the control signal applied from the control unit 100. A cooling fan motor 16 providing forced air is mounted.

The coolant pump 12 is mounted on the coolant flow path between the water temperature controller 120 and the engine 10, is connected to the engine accessory and a belt or chain, and is operated according to the engine start-up to provide forced circulation of coolant. .

The cooling water pump 12 may be applied as an electric water pump whose on/off and driving amount are adjusted according to a control signal applied from the controller 100 .

The water temperature controller 120 is mounted at a predetermined position of the coolant flow path connecting the engine and the radiator 11 to control the circulation direction and flow rate of the coolant. At this time, the water temperature controller 120 may adjust the CAM to change the RVC (Rotary valve for coolant temperature management) angle, and determine the flow direction of the coolant according to the RVC angle.

The water temperature controller 120 may control the cooling water distributed to the heater core (not shown) and the radiator 11 , respectively.

The temperature sensor 200 detects the temperature of the coolant discharged from the engine 10 through forced circulation by the coolant pump 12 , and provides information thereto to the controller 100 .

The controller 100 controls the water temperature controller 120 to variably control the coolant temperature.

The controller 100 diagnoses the failure of the water temperature controller 120 by comparing the model temperature of the coolant and the actual temperature measured by the temperature sensor 17 with a preset temperature, and as a result of the diagnosis, diagnoses that the water temperature controller 120 is malfunctioning. In this case, the valve angle of the water temperature controller 120 is controlled, and the failure of the water temperature controller 120 is rediagnosed based on the change in the temperature of the coolant according to the valve angle control.

Conventionally, when the coolant model temperature reached the critical temperature, but the actual measured temperature did not reach the diagnostic temperature, the water temperature controller 120 was diagnosed as a failure. As such, when determining whether the water temperature controller 120 is malfunctioning using only the model temperature and the actual temperature, when the behavior of the model temperature and the actual temperature is different, there is a problem in that the normal water temperature controller 120 is diagnosed as a failure. Therefore, it is necessary to determine the failure by checking the actual coolant temperature through the opening degree of the water temperature controller 120 under a specific condition, rather than simply judging it at a specific critical position according to the temperature rise.

Accordingly, the control unit 100 of the present invention does not observe only the model temperature and the measured actual temperature, but uses the mechanical characteristics of the water temperature controller 120 to adjust the RVC angle to stop the flow of the cooling water to control the temperature of the cooling water. Increase or decrease the cooling water temperature by changing the cooling water flow path toward the radiator 11, and rediagnosing the failure of the water temperature controller 120 based on the temperature change value of the cooling water. That is, the control unit 100 changes the RVC angle of the water temperature controller 120 to a flow stop section to induce an increase in the cooling water temperature, and after a certain period of time, the cooling water flow path is completely opened toward the radiator 11 to reduce the cooling water temperature. induce Then, the controller 100 determines that the water temperature controller 120 is normal if the rise and fall of the coolant temperature meet the criteria, and if it does not meet the criteria, the controller 100 finally diagnoses the water temperature controller 120 as a failure.

Hereinafter, the operation of the control unit 100 will be described in detail.

The controller 100 compares the model temperature of the coolant with a preset critical temperature, and when the model temperature exceeds the critical temperature, compares the actual temperature of the coolant with a preset diagnostic temperature, and the comparison result shows that the actual temperature is less than the diagnostic temperature. In this case, the water temperature controller 120 is diagnosed as a failure. That is, the controller 100 derives a model temperature (value) by modeling the coolant temperature based on the outside air temperature value, information on the load of the engine, and the coolant temperature value at startup, and uses the temperature sensor 200 to determine the coolant temperature. By measuring the temperature, the actual temperature of the cooling water can be derived. At this time, since the method of the controller 100 modeling the coolant temperature to derive the model temperature (value) uses a conventional method, a detailed description thereof will be omitted. Then, the controller 100 may diagnose the normality or failure of the water temperature controller 120 using the model temperature and the actual temperature of the coolant.

When the water temperature controller 120 is diagnosed as malfunctioning, the controller 100 increases the coolant temperature by changing the angle of the water temperature controller 120 valve to a flow stop section. Here, changing the angle of the valve to the flow stop section may mean closing all the valves of the water temperature controller 120, and when all the valves of the water temperature controller 120 are closed, the coolant does not flow through the coolant flow path, The coolant temperature may rise. For example, in order to increase the temperature of the coolant, the controller 100 operates the valve of the water temperature controller 120 through a first coolant flow passage through which the coolant distributed to the heater core flows, a second coolant flow passage through which the coolant distributed to the radiator 11 flows, and It can be changed to a flow stop section that blocks the third coolant flow path through which the coolant discharged from the cylinder block flows.

Then, when a predetermined time has elapsed, the controller 100 opens the valve of the water temperature controller 120 to lower the coolant temperature. In this case, the control unit 100 may maximize the opening rate of the second cooling water passage through which the cooling water distributed to the radiator 11 flows in order to lower the temperature of the cooling water.

Then, the control unit 100 re-diagnosing the failure of the water temperature controller 120 based on the temperature increase value due to the increase in the cooling water temperature and the temperature decrease value due to the decrease in the cooling water temperature. That is, the controller 100 compares the temperature rise value with a preset first reference value, and if the comparison result does not exceed the first reference value, the controller 100 may determine the water temperature controller 120 as a failure. If the temperature increase value exceeds the first reference value, the controller 100 compares the temperature decrease value due to the decrease in the cooling water temperature with a preset second reference value. When the temperature drop value exceeds the second reference value, the controller 100 may determine that the water temperature controller 120 is normal, and if it does not exceed the second reference value, the controller 100 may determine that the water temperature controller 120 is malfunctioning. In this case, the first reference value and the second reference value may be the same or different values.

The control unit 100 may be implemented as one or more microprocessors operated by a set program, and the set program may include a series of instructions for performing a method according to an embodiment of the present invention to be described later.

2 is a partial perspective view of a water temperature controller according to an embodiment of the present invention.

Referring to FIG. 2 , the water temperature controller 120 according to an embodiment of the present invention includes a motor 105 , a gearbox 110 , a cam 300 , a profile 302 , a rod 322 , and a valve 320 . , an elastic member 324 , and a support member 326 .

The control unit 100 controls the power applied to the motor 105 according to operating conditions such as coolant temperature, and the motor 105 rotates the cam 300 through the gearbox 110 .

The cam 300 has a disk shape, and a profile 302 having an inclined surface set in the rotational direction is formed on the lower surface of the cam 300, and the profile 302 has a set inclination and height. That is, a profile 302 having a set inclination and height is formed on the lower surface of the cam 300 , and the profile 302 pushes the upper end of the rod 322 downward according to the rotational position of the cam 300 .

Accordingly, while the elastic member 324 is compressed, the valve 320 may open and close the coolant flow path. Here, the opening rate of the coolant passage may be controlled according to the rotational position of the cam 300 .

The valve 320 has a flat lower surface, a pointed hat shape toward the upper portion of the center, and a rod 322 is connected to the upper end thereof, and the rod 322 extends to the upper portion by a set length.

The upper end of the rod 322 corresponds to the profile 302 of the cam 300 , the valve 320 is disposed in the middle portion of the rod 322 , and the elastic member 324 has the lower surface of the valve 320 as the upper portion. supported by Thus, the top of the rod 322 is in contact with the profile 302 .

As shown in FIG. 2 , three profiles 302 are formed on the lower surface of the cam 300 , and three rods 322 and a valve 320 are configured to correspond to each profile 302 .

Accordingly, the water temperature controller 120 according to the embodiment of the present invention may control the opening rate of the three coolant flow paths (not shown) through the three valves 320 . Here, the number of the profile 302 and the valve 320 may be changed according to design specifications.

In addition, the structure of the water temperature controller 120 according to the embodiment of the present invention is not limited to the description of FIG. 2 , and may optionally include a structure of the already known water temperature controller 120 .

FIG. 3 is a block diagram schematically showing the configuration of an apparatus for diagnosing a failure of a water temperature controller according to an embodiment of the present invention, and FIG. 4 is a view for explaining a coolant flow path according to an embodiment of the present invention.

3 and 4, the malfunction diagnosis apparatus of the water temperature controller 120 according to an embodiment of the present invention includes a control unit 100, a motor 105, a cam 300, a valve 320, and a temperature sensor ( 100) is included.

The controller 100 controls the motor 105 using the operating conditions (coolant temperature, outside temperature, etc.) and the position of the cam 300 , and the motor 105 rotates the cam 300 through the gear box 110 . change the position. At this time, the control unit 100 may receive the rotational position of the cam detected by the cam position detection sensor (not shown), and detect the rotational position of the motor 105 through a resolver (not shown) to detect the rotational position of the cam 300 ) can be calculated indirectly.

On the lower surface of the cam 300, three profiles 302 are formed, and correspondingly, three rods and three valves 320a, 320b, and 320c are configured. Here, it is obvious that the first, second, and third coolant flow paths are formed in correspondence with the respective valves 320a, 320b, and 320c.

Referring to FIG. 4 , the first coolant flow passage is connected to the heater core, the second coolant flow passage is connected to the radiator 11 , and the third coolant flow passage is connected to an automatic transmission fluid (ATF).

The opening rates of the first, second, and third coolant passages may be controlled according to the rotational position of the cam 300 .

5 is a flowchart illustrating a method for diagnosing a failure of the water temperature controller 120 according to an embodiment of the present invention.

Referring to FIG. 5 , the controller 100 increases or decreases the coolant model temperature according to the operating conditions ( S510 ), and determines whether the coolant model temperature exceeds a preset threshold temperature ( S520 ).

If it is determined in step S520 that the coolant model temperature exceeds the threshold temperature, the controller 100 determines whether the actual temperature of the coolant is less than a preset diagnosis temperature (S530). The controller 100 may receive the actual temperature of the coolant measured by the temperature sensor and compare it with the diagnosis temperature.

As a result of the determination in step S530, if the actual temperature is less than the diagnosis temperature, the controller 100 diagnoses the water temperature controller 120 as a failure and converts the water temperature controller 120 valve 320 into a flow stop section (S540). At this time, the control unit 100 discharges the valve 320 of the water temperature controller 120 from the first cooling water flow path through which the cooling water distributed to the heater core flows, the second cooling water flow path through which the cooling water distributed to the radiator 11 flows, and the cylinder block. The cooling water temperature may be increased by changing to a flow stop section that blocks the third cooling water flow path through which the cooling water flows.

When step S540 is performed, the controller 100 opens the valve 320 of the water temperature controller 120 to lower the coolant temperature (S550). In this case, the control unit 100 may control the opening rate of the second cooling water passage through which the cooling water distributed to the radiator 11 flows to the maximum to decrease the cooling water temperature.

When step S560 is performed, the control unit 100 determines whether a temperature increase value due to an increase in the coolant temperature exceeds a preset first reference value (S560),

As a result of the determination in step S560, if the temperature increase value exceeds the first reference value, the controller 100 determines whether the temperature decrease value due to the decrease in the cooling water temperature exceeds a preset second reference value (S570).

As a result of the determination in step S570, if the temperature drop exceeds the second reference value, the control unit 100 determines that the water temperature controller 120 is normal (S580).

If, as a result of the determination in step S570, the temperature drop value does not exceed the second reference value, the controller 100 finally determines that the water temperature controller 120 is malfunctioning (S590).

If, as a result of the determination in step S560, the temperature rise value does not exceed the first reference value, the control unit 100 finally determines that the water temperature controller 120 is malfunctioning.

On the other hand, in the embodiment of the present invention, the controller 100 diagnoses the failure of the water temperature controller 120 based on the model temperature of the coolant and the actual temperature measured by the temperature sensor 200, and the diagnosis result is the water temperature controller 120. is diagnosed as a failure, the valve angle of the water temperature controller 120 is controlled and the failure of the water temperature controller 120 is rediagnosed based on the change in the temperature of the coolant according to the valve angle control, but the controller 100 ) does not diagnose the failure of the water temperature controller 120 based on the model temperature and the actual temperature of the coolant, but the failure of the water temperature controller 120 based on the temperature change value of the coolant according to the valve angle control of the water temperature controller 120 can be diagnosed

In this case, the controller 100 may control the valve angle of the water temperature controller 120 and diagnose the failure of the water temperature controller based on the change in the temperature of the coolant according to the valve angle control. That is, the control unit 100 changes the valve angle to a flow stop section to increase the coolant temperature, and when a predetermined time has elapsed, the control unit 100 opens the valve 320 to lower the coolant temperature, and the temperature caused by the increase in the coolant temperature A failure of the water temperature controller 120 may be diagnosed based on the increase value and the temperature decrease value due to the decrease in the cooling water temperature. A method for the controller 100 to diagnose a failure of the water temperature controller 120 based on the temperature rise value and the temperature drop value will be referred to the above-described method.

As described above, in the method and apparatus for diagnosing a failure of a water temperature controller according to an embodiment of the present invention, the water temperature controller does not use only the model temperature and actual temperature of the coolant. By changing the rotational opening angle of the inside, it is possible to directly check whether the temperature actually changes, thereby increasing the robustness to the fault diagnosis of the water temperature controller and preventing erroneous diagnosis.

Although the present invention has been described with reference to the embodiment shown in the drawings, this is merely an example, and those skilled in the art to which various modifications and equivalent other embodiments are possible. will understand Accordingly, the true technical protection scope of the present invention should be defined by the following claims.

10 : engine
11: Radiator
12: coolant pump
13: coolant flow path
14: Bypass Euro
16: cooling fan motor
100: control unit
120: water temperature controller
105: motor
110: gear box
300 : cam
302: Profile
322 : load
320: valve
324: elastic member
326: support member

Claims (21)

diagnosing, by the controller, a failure of the water temperature controller by comparing the model temperature and the actual temperature of the coolant with a preset temperature; and
When it is diagnosed that the water temperature controller is malfunctioning, the control unit controls the valve angle of the water temperature controller, and the step of rediagnosing the failure of the water temperature controller based on the temperature change value of the coolant according to the valve angle control,
Rediagnosing the failure of the water temperature controller comprises:
changing the valve angle to a flow stop section by the controller to increase the coolant temperature;
when a predetermined period of time has elapsed, the control unit opening the valve to lower the coolant temperature; and
and rediagnosing, by the control unit, a failure of the water temperature controller based on a temperature rise value due to an increase in the cooling water temperature and a temperature decrease value due to a decrease in the cooling water temperature. .
According to claim 1,
Diagnosing the failure of the water temperature controller comprises:
comparing, by the controller, the model temperature of the coolant with a preset critical temperature;
comparing, by the controller, the actual temperature of the cooling water with a preset diagnosis temperature when the model temperature exceeds a threshold temperature; and
and diagnosing, by the controller, as a failure of the water temperature controller when the actual temperature is less than the diagnosis temperature.
delete According to claim 1,
The step of rediagnosing the failure of the water temperature controller based on a temperature rise value due to an increase in the cooling water temperature and a temperature decrease value due to a decrease in the cooling water temperature includes:
comparing, by the controller, the temperature rise value with a preset first reference value;
comparing the temperature drop value with a preset second reference value when the temperature rise value exceeds the first reference value; and
and determining that the water temperature controller is normal when the temperature drop value exceeds the second reference value, and determining that the water temperature controller is malfunctioning when it does not exceed the second reference value. How to diagnose a breakdown.
5. The method of claim 4,
When the temperature rise value does not exceed the first reference value, the water temperature controller failure diagnosis method, characterized in that it is determined that the failure of the water temperature controller.
According to claim 1,
The step of increasing the coolant temperature by changing the valve angle to a flow stop section includes:
A flow stop section that blocks the first cooling water flow path through which the coolant distributed to the heater core flows, the second cooling water flow path through which the cooling water distributed to the radiator 11 flows, and the third cooling water flow path through which the cooling water distributed to the ATF (automatic transmission fluid) flows A method for diagnosing a failure of a water temperature controller, characterized in that the valve is controlled with a
According to claim 1,
The step of lowering the coolant temperature by opening the valve,
A method for diagnosing a failure of a water temperature regulator, characterized in that the valve is controlled so that the opening rate of the second coolant flow passage through which the coolant distributed to the radiator flows is maximized.
controlling the valve angle of the water temperature controller by the controller; and
diagnosing, by the control unit, a failure of the water temperature controller based on a temperature change value of the coolant according to the valve angle control;
The step of controlling the valve angle of the water temperature controller,
changing the valve angle to a flow stop section by the controller to increase the coolant temperature; and
and when a predetermined period of time has elapsed, the controller opens the valve to lower the coolant temperature.
delete 9. The method of claim 8,
The step of increasing the coolant temperature by changing the valve angle to a flow stop section includes:
A flow stop section that blocks the first cooling water flow path through which the coolant distributed to the heater core flows, the second cooling water flow path through which the cooling water distributed to the radiator 11 flows, and the third cooling water flow path through which the cooling water distributed to the ATF (automatic transmission fluid) flows A method for diagnosing a failure of a water temperature controller, characterized in that the valve is controlled with a
9. The method of claim 8,
The step of lowering the coolant temperature by opening the valve,
A method for diagnosing a failure of a water temperature regulator, characterized in that the valve is controlled so that the opening rate of the second coolant flow passage through which the coolant distributed to the radiator flows is maximized.
9. The method of claim 8,
Diagnosing the failure of the water temperature controller comprises:
comparing, by the controller, a temperature rise value due to an increase in the coolant temperature with a preset first reference value;
when the temperature rise value exceeds the first reference value, comparing, by the controller, a temperature drop value due to a drop in the cooling water temperature with a preset second reference value; and
and determining that the water temperature controller is normal when the temperature drop value exceeds the second reference value, and determining that the water temperature controller is malfunctioning when it does not exceed the second reference value. How to diagnose a breakdown.
13. The method of claim 12,
When the temperature rise value does not exceed the first reference value, the water temperature controller failure diagnosis method, characterized in that it is determined that the failure of the water temperature controller.
a water temperature controller mounted at a predetermined position of a coolant flow path connecting the engine and the radiator to control a circulation direction and flow rate of the coolant;
a temperature sensor for measuring the temperature of the cooling water; and
A control unit for variably controlling the temperature of the cooling water by controlling the water temperature controller,
The control unit controls a valve angle of the water temperature controller, and diagnoses a failure of the water temperature controller based on a temperature change value of the coolant according to the valve angle control,
The control unit is
The valve angle is changed to a flow stop section to increase the coolant temperature, and when a predetermined time has elapsed, the valve is opened to lower the coolant temperature, and the temperature rise value due to the increase in the coolant temperature and the coolant temperature A failure diagnosis apparatus for a water temperature controller, characterized in that the failure of the water temperature controller is diagnosed based on a temperature drop value due to the drop.
delete 15. The method of claim 14,
The control unit is
In order to increase the temperature of the coolant, a first coolant passage through which the coolant distributed to the heater core flows through the valve, a second coolant passage through which the coolant distributed to the radiator flows, and a third coolant through which the coolant distributed to an automatic transmission fluid (ATF) flows through the valve A failure diagnosis device for a water temperature controller, characterized in that it is controlled by a flow stop section that blocks the cooling water flow path.
15. The method of claim 14,
The control unit is
The apparatus for diagnosing a failure of a water temperature regulator, characterized in that the valve is controlled to maximize an opening rate of a second cooling water passage through which the cooling water distributed to the radiator flows to lower the temperature of the cooling water.
15. The method of claim 14,
The control unit is
The temperature rise value is compared with a preset first reference value, and when the temperature rise value exceeds the first reference value as a result of the comparison, the temperature drop value is compared with a preset second reference value, and as a result of the comparison, the temperature When the falling value exceeds the second reference value, it is determined that the water temperature controller is normal, and when it does not exceed the second reference value, it is determined that the water temperature controller is malfunctioning.
19. The method of claim 18,
The control unit is
If the temperature rise value does not exceed the first reference value, the water temperature controller failure diagnosis apparatus, characterized in that it is determined that the failure of the water temperature controller.
15. The method of claim 14,
The control unit is
The failure of the water temperature controller is diagnosed by comparing the model temperature of the coolant and the actual temperature measured by the temperature sensor with a preset temperature. and rediagnosing the failure of the water temperature controller based on a temperature change value of the coolant according to the valve angle control.
21. The method of claim 20,
The control unit is
The model temperature of the coolant is compared with a preset critical temperature, and when the model temperature exceeds the critical temperature, the actual temperature of the coolant is compared with a preset diagnostic temperature, and as a result of the comparison, the actual temperature is less than the diagnostic temperature In this case, a failure diagnosis device of the water temperature controller, characterized in that the diagnosis of the failure of the water temperature controller.

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