Temperature regulator fault diagnosis method and device, engine and vehicle

Abstract

The invention discloses a thermolator fault diagnosis method and device, an engine and a vehicle, and the thermolator fault diagnosis method comprises the steps: when the outlet water temperature T1 of an engine body is larger than a preset value, whether a thermolator breaks down or not is judged according to the outlet water temperature T1 of the engine body, the outlet water temperature T2 of a first radiator and the medium temperature T3 after heat exchange between a second radiator and outlet water of the engine body. Compared with the prior art, judgment factors are increased, the misjudgment probability can be reduced, and vehicle fault solving is facilitated.

Description

Technical Field

[0001] The present application relates to the field of engine technology, and in particular to a thermostat fault diagnosis method and device, an engine and a vehicle. Background Art

[0002] The thermostat is a valve component that controls the coolant of the engine body to dissipate heat to the radiator. When the thermostat cannot be opened or the opening stroke is insufficient, the coolant of the body cannot enter the radiator or the flow entering the radiator is insufficient, which will cause the body water temperature to rise sharply and alarm. At the same time, the radiator outlet temperature does not change with the body outlet temperature or the difference between the radiator outlet temperature and the body outlet temperature is large. The existing technology usually determines the thermostat failure through the above fault conditions.

[0003] In actual situations, there are other factors that can cause similar faults. Judging thermostat faults only by the body water outlet temperature and the radiator water outlet temperature may lead to misjudgment, which is not conducive to vehicle fault resolution. Summary of the invention

[0004] The purpose of the present application is to provide a thermostat fault diagnosis method, an engine and a fault diagnosis method thereof, so as to solve the problem of misjudgment of thermostat fault.

[0005] To achieve the purpose of this application, this application provides the following technical solutions:

[0006] In a first aspect, the present application provides a thermostat fault diagnosis method, the thermostat fault diagnosis method is used for an engine, the engine comprising a water pump, a body, a thermostat, a first radiator, and a second radiator, the body being in communication with a water outlet of the water pump, the thermostat and the second radiator being in communication with the water outlet of the body respectively, the first radiator being in communication with the water outlet of the thermostat, the water outlet of the first radiator being in communication with a water inlet of the water pump, and the water outlet of the second radiator being in communication with a water inlet of the water pump;

[0007] The thermostat fault diagnosis method comprises:

[0008] When the outlet water temperature T1 of the machine body is greater than a predetermined value, the thermostat is judged to be faulty according to the outlet water temperature T1 of the machine body, the outlet water temperature T2 of the first radiator, and the medium temperature T3 after heat exchange between the second radiator and the outlet water of the machine body.

[0009] In one embodiment, it includes: if the water outlet temperature T2 of the first radiator follows the water outlet temperature T1 of the body within a predetermined time, and △T>a, T3>b, A>H, then the result of the thermostat failure is output; wherein △T is the difference between the water outlet temperature T1 of the body and the water outlet temperature T2 of the first radiator, a is a first threshold value, b is a second threshold value, A is the start time of the water outlet temperature T2 of the first radiator to rise, and H is the longest time required for the thermostat to open normally.

[0010] In one embodiment, the thermostat is an electronic thermostat, and the thermostat includes a mechanical module and an electronic control module;

[0011] If the outlet water temperature T2 of the first radiator changes with the outlet water temperature T1 of the body, and ΔT>a, T3>b, and H<A≤I, then the result of the performance attenuation of the electronic control module of the thermostat is output;

[0012] Wherein, I is the shortest time required for the thermostat to be turned on only by the mechanical module.

[0013] In one embodiment, the thermostat is an electronic thermostat, which includes a mechanical module and an electronic control module; if the outlet water temperature T2 of the first radiator follows the outlet water temperature T1 of the body within a predetermined time, and △T>a, T3>b, A>H, and A>I, then the result of the failure of the electronic control module of the thermostat is output; wherein I is the shortest time required for the thermostat to be opened only by the mechanical module.

[0014] In one embodiment, the thermostat is an electronic thermostat, which includes a mechanical module and an electronic control module; if the water outlet temperature T2 of the first radiator follows the water outlet temperature T1 of the body within a predetermined time, and △T>a, T3>b, A>H, and I<A≤J, then the result that the mechanical module of the thermostat is normal and the electronic control module is invalid is output; wherein I is the shortest time required for the thermostat to be turned on only by the mechanical module, and J is the longest time required for the thermostat to be turned on only by the mechanical module.

[0015] In one embodiment, if the water outlet temperature T2 of the first radiator follows the water outlet temperature T1 of the body within a predetermined time, and △T>a, T3>b, A>H, and A>J, then the result that both the mechanical module and the electronic control module of the thermostat fail is output; wherein J is the maximum time required for the thermostat to be opened only by the mechanical module.

[0016] In one embodiment, when outputting the result of failure of the electronic control module, if e≤R≤f, then further outputting the result of failure of the control circuit of the electronic control module; wherein R is the resistance value of the electronic control module of the thermostat, and e and f are both preset resistance fluctuation values.

[0017] In one embodiment, when the result of the failure of the electronic control module is output, if R<e or R>f, the result of the resistance failure of the electronic control module is further output; wherein R is the resistance value of the electronic control module of the thermostat, and e and f are both preset resistance fluctuation values.

[0018] In one implementation, it includes: if the outlet water temperature T2 of the first radiator does not change with the outlet water temperature T1 of the machine body within a predetermined time, outputting a result of the thermostat failure.

[0019] In a second aspect, the present application further provides a thermostat fault diagnosis device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor is used to execute the computer program to implement a thermostat fault diagnosis method as described in any one of the various embodiments of the first aspect.

[0020] In the third aspect, the present application also provides an engine, comprising a water pump, a body, a thermostat, a first radiator and a second radiator, the body being connected to the water outlet of the water pump, the thermostat and the second radiator being connected to the water outlet of the body respectively, the first radiator being connected to the water outlet of the thermostat, the water outlet of the first radiator being connected to the water inlet of the water pump, and the water outlet of the second radiator being connected to the water inlet of the water pump; the engine diagnoses faults using a thermostat fault diagnosis method as described in any one of the various embodiments of the first aspect.

[0021] In a fourth aspect, the present application also provides a vehicle, comprising the engine described in the third aspect.

[0022] The thermostat fault diagnosis method of the present application can determine that the engine is faulty when the water outlet temperature T1 of the engine body is greater than a predetermined value. The cause of the engine failure may be a thermostat failure. Then, based on the water outlet temperature T1 of the engine body, the water outlet temperature T2 of the first radiator, and the warm air temperature T3 supplied by the second radiator, it is determined whether the thermostat is faulty. This increases the judgment factors, can reduce the probability of misjudgment, and is beneficial to vehicle fault resolution. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0024] Figure 1 is a schematic diagram of an engine of an embodiment;

[0025] Figure 2 The present invention is a flowchart of a thermostat fault diagnosis method according to an embodiment.

[0026] Description of reference numerals:

[0027] 10 - water pump, 20 - machine body, 30 - thermostat, 40 - first radiator, 50 - second radiator, 61 - first sensor, 62 - second sensor, 63 - third sensor. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0029] It should be noted that when a component is said to be "fixed to" another component, it can be directly on the other component or there can be a central component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there can be a central component at the same time.

[0030] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used in this application and in the specification are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used in this application includes any and all combinations of one or more of the related listed items.

[0031] In conjunction with the accompanying drawings, some embodiments of the present application are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0032] Please refer to Figure 1An engine provided in an embodiment of the present application includes a water pump 10, a body 20, a thermostat 30, a first radiator 40 and a second radiator 50.

[0033] The body 20 is connected to the water outlet of the water pump 10, the thermostat 30 and the second radiator 50 are respectively connected to the water outlet of the body 20, the first radiator 40 is connected to the water outlet of the thermostat 30, the water outlet of the first radiator 40 is connected to the water inlet of the water pump 10, and the water outlet of the second radiator 50 is connected to the water inlet of the water pump 10.

[0034] Optionally, the engine further includes a first sensor 61 , a second sensor 62 and a third sensor 63 .

[0035] The water pump 10 is a coolant driving mechanism. The water pump 10 can be of any feasible type, and the coolant can be water or other coolants, without limitation.

[0036] The engine body 20 is connected with the water outlet of the water pump 10, specifically, the engine body 20 is connected with the water outlet of the water pump 10 through a water pipe or other pipeline. The connection mentioned in the following text is all through a water pipe or other pipeline, which is specially explained and will not be repeated in the following text. The engine body 20 may include a cylinder body, a cylinder head, and a cylinder body water jacket, a cylinder head water jacket, etc. arranged around the cylinder body. The engine body 20 is connected with the water outlet of the water pump 10 in that the cylinder body water jacket, the cylinder head water jacket, etc. are connected with the cooling mechanism located on the periphery of the cylinder body and the cylinder head and the water outlet of the water pump 10. When the coolant transported by the water pump 10 flows through the cylinder body water jacket, the cylinder head water jacket and other structures, it can take away the heat of the cylinder body and the cylinder head, thereby achieving a cooling and heat dissipation effect.

[0037] The first radiator 40 may be any feasible radiator for lowering the temperature of the coolant. The second radiator 50 may be a component on the vehicle that needs to absorb heat, specifically a heater, a battery assembly that needs to be preheated, etc. The following embodiments are described by taking the second radiator 50 as a heater as an example.

[0038] The first sensor 61 is connected to the water outlet of the machine body 20. The first sensor 61 is a temperature sensor, and the specific type is not limited. The first sensor 61 is used to measure the temperature of the coolant at the water outlet of the machine body 20, which is the water outlet temperature T1 of the machine body 20. The water outlet temperature T1 of the machine body 20 in the following text is the temperature of the coolant at the water outlet of the machine body 20 measured by the first sensor 61.

[0039] According to the water outlet temperature T1 of the body 20, it can be determined whether the engine is faulty. Specifically, if the water outlet temperature T1 of the body 20 is greater than a predetermined value, it is determined that the coolant at the water outlet of the body 20 has not entered the subsequent cooling mechanism for circulation to dissipate heat, and the coolant stays at the water outlet of the body 20, indicating an engine fault. The cause of the fault may be a thermostat 30 fault and a first radiator 40 fault, etc., which are not limited. The embodiment of the present application also provides a thermostat 30 fault diagnosis method for determining whether the engine fault is caused by a thermostat 30 fault, which will be described in detail later.

[0040] The thermostat 30 and the second radiator 50 are respectively connected to the water outlet of the first sensor 61. Specifically, the thermostat 30 is an electronic thermostat, which includes a mechanical module and an electric control module. The mechanical module may include a wax bag, and the electric control module may include an electric heating component for heating the wax bag. Compared with the traditional thermostat, the electronic thermostat has an additional electric control module. When the electric control module of the electronic thermostat opens the valve, the electric heating component is controlled by an electronic signal to heat the wax bag, so that the wax bag melts and then opens the valve. When the mechanical module opens the valve, the high-temperature liquid flowing into the electronic thermostat heats the wax bag by itself, so that the wax bag melts and then opens the valve. The electronic thermostat can open the valve through at least one of the mechanical module and the electronic module, and can also open and control the opening of the valve. For the specific structure of the electronic thermostat, any feasible electronic thermostat in the prior art can be specifically referred to without limitation. The coolant flowing out of the first sensor 61 can flow to the thermostat 30 and the second radiator 50.

[0041] The first radiator 40 is connected to the water outlet of the thermostat 30. If the thermostat 30 is not faulty and its internal valve is open and the opening is large enough, the coolant can flow through the thermostat 30 to the first radiator 40 for heat dissipation. If the thermostat 30 is faulty, its internal valve cannot be opened, or the opening is too small, the coolant cannot flow to the first radiator 40, or too little coolant flows to the first radiator 40, which will result in poor heat dissipation effect.

[0042] The second sensor 62 is connected to the water outlet of the first radiator 40. The second sensor 62 is a temperature sensor, and the specific type is not limited. The second sensor 62 is used to measure the temperature of the coolant at the water outlet of the first radiator 40, which is the water outlet temperature T2 of the first radiator 40. The water outlet temperature T2 of the first radiator 40 in the following text is the temperature of the coolant at the water outlet of the first radiator 40 measured by the second sensor 62.

[0043] The third sensor 63 is disposed on the second radiator 50. The coolant flowing out of the body 20 absorbs the high temperature of the body 20, flows through the first sensor 61 to the second radiator 50 (taking the second radiator 50 as a heater as an example), and heats the second radiator 50, thereby providing warm air for the vehicle. The third sensor 63 is a temperature sensor, and the specific type is not limited. The third sensor 63 is used to measure the medium temperature T3 after the water outlet heat exchange between the second radiator 50 and the body 20, that is, the warm air temperature supplied by the heater.

[0044] The water outlets of the second radiator 50 and the second sensor 62 are respectively connected to the water inlet of the water pump 10. The coolant heats the second radiator 50 to reduce its temperature, dissipates heat at the first radiator 40 to reduce its temperature, and then is transported back to the water pump 10, thereby realizing the recycling of the coolant. The inlet of the water pump 10 contains coolant at a lower temperature, thereby achieving a better cooling effect of the machine body 20.

[0045] In the embodiment of the present application, the engine uses the engine fault diagnosis method provided in the embodiment of the present application to diagnose the fault. The engine fault diagnosis method provided in the embodiment of the present application includes the thermostat 30 fault diagnosis method in any embodiment of the present application.

[0046] By adopting the thermostat 30 fault diagnosis method in the embodiment of the present application, the problem of misjudgment of thermostat 30 fault can be solved, which is beneficial to vehicle fault resolution and resource saving.

[0047] The following is a detailed description of the thermostat 30 fault diagnosis method according to the embodiment of the present application.

[0048] Please refer to Figure 1 and Figure 2 The embodiment of the present application provides a thermostat 30 fault diagnosis method, which can be implemented by executing a thermostat 30 fault diagnosis device. Specifically, the thermostat 30 fault diagnosis device includes a memory and a processor, the memory stores a computer program, and the processor is used to execute the computer program to implement the thermostat 30 fault diagnosis method in the embodiment of the present application.

[0049] The thermostat 30 fault diagnosis method in the embodiment of the present application includes: when the water outlet temperature T1 of the body is greater than a predetermined value, judging whether the thermostat is faulty according to the water outlet temperature T1 of the body, the water outlet temperature T2 of the first radiator, and the warm air temperature T3 supplied by the second radiator.

[0050] Specifically, the outlet water temperature T1 of the machine body 20 is first obtained.

[0051] Among them, the first sensor 61 senses the temperature of the coolant at the water outlet of the body 20 in real time, obtains the water outlet temperature T1 of the body 20, and transmits the signal of temperature T1 to the processor. The processor can determine whether the engine is faulty according to the temperature T1. When the temperature T1 is at a lower level but not greater than the predetermined value, it can be determined that the engine is faulty and operates normally; when the temperature T1 is higher and greater than the predetermined value, it can be determined that the engine cooling fails and the engine is faulty. Whether it is the thermostat 30 that is faulty or other components that are faulty needs to be determined through subsequent steps. The unit of temperature T1 is degrees Celsius (℃).

[0052] Afterwards, the outlet water temperature T2 of the first radiator 40 is obtained.

[0053] The second sensor 62 senses the temperature of the coolant at the outlet of the first radiator 40 in real time, that is, the outlet water temperature T2 of the first radiator 40, and transmits a signal of the temperature T2 to the processor. The unit of the temperature T2 is Celsius (°C).

[0054] After obtaining the temperature T1 and the temperature T2, it can be determined whether the thermostat 30 is faulty according to whether the outlet water temperature T2 of the first radiator 40 changes with the outlet water temperature T1 of the body 20.

[0055] When the machine body 20 is just started, the temperature T1 is relatively low, and no coolant is needed for cooling, so the thermostat 30 may not be turned on. As the machine body 20 runs, the temperature T1 gradually increases. When the temperature T1 reaches the target opening temperature of the thermostat 30, by comparing whether the temperature T2 changes with the temperature T1, it can be determined whether the thermostat 30 is turned on. The temperature T2 changes with the temperature T1, which means that the temperature T2 changes with the temperature T1 in the same trend within a certain range. If the temperature T1 increases, the temperature T2 also increases within a certain time range. It should be understood that the increase in the temperature T1 may be different from the increase in the temperature T2, but they should increase and decrease in the same manner.

[0056] If temperature T2 does not change with temperature T1, it is determined that the thermostat 30 is not turned on, and the reason for not turning on may be that the thermostat 30 is faulty or there is a lot of air at the thermostat 30. If temperature T2 changes with temperature T1, subsequent steps are also required to determine whether the thermostat 30 is faulty.

[0057] Afterwards, the medium temperature T3 after the heat exchange between the outlet water of the second radiator 50 and the body 20 is obtained.

[0058] The third sensor 63 senses the temperature T3 of the warm air supplied by the second radiator in real time, and transmits a signal of the temperature T3 to the processor. The unit of the temperature T3 is Celsius (°C).

[0059] Since there may be misjudgment in judging whether the thermostat 30 is faulty based on the temperature T1 and the temperature T2, the temperature T3 is introduced to judge whether the thermostat 30 is faulty. This increases the judgment factor and can reduce the probability of misjudgment.

[0060] Among them, the coolant flowing out of the water outlet of the body 20 flows through the first sensor 61, and then flows through the thermostat 30 and the second radiator 50 in two ways, that is, the coolant with temperature T1 will flow to the thermostat 30 and the second radiator 50 at the same time. Therefore, according to the temperature T3, it can be judged whether the thermostat 30 is faulty.

[0061] In summary, after obtaining temperature T1, temperature T2 and temperature T3, it is possible to determine whether the thermostat is faulty. As for how to determine specifically, any feasible determination method can be used, and the method in the subsequent embodiments of this application can also be used, without limitation.

[0062] The current thermostat diagnosis method only uses the body water outlet temperature T1 and the first radiator water outlet temperature T2 to determine the thermostat failure, which may lead to misjudgment and is not conducive to vehicle fault resolution.

[0063] Compared with the method of only relying on T1 and T2 to determine whether the thermostat is faulty, this embodiment also takes into account the influence of the water pump flow on T1 and T2, introduces the warm air temperature T3, and after eliminating the influence of the water pump flow, determines whether the changes in T1 and T2 are caused by a thermostat failure.

[0064] In the embodiment of the present application, when the water outlet temperature T1 of the body 20 is greater than a predetermined value, it can be judged that the engine is faulty, and the cause of the engine failure may be a failure of the thermostat 30. Then, based on the water outlet temperature T1 of the body 20, the water outlet temperature T2 of the first radiator 40, and the medium temperature T3 after the heat exchange between the water outlet of the second radiator 50 and the body 20, it is judged whether the thermostat 30 is faulty. This increases the judgment factors, can reduce the probability of misjudgment, and is beneficial to the resolution of vehicle faults.

[0065] If the outlet water temperature T2 of the first radiator 40 changes with the outlet water temperature T1 of the housing 20 , it is determined whether the thermostat 30 is faulty based on whether the relationship ΔT≤a is satisfied.

[0066] Among them, △T is the difference between the water outlet temperature T1 of the body 20 and the water outlet temperature T2 of the first radiator 40, a is the first threshold, which is a preset temperature difference determined by experiments, that is, the temperature difference between temperature T1 and temperature T2 measured when the engine is normal, and the unit of a is degrees Celsius (℃).

[0067] Specifically, if the temperature T2 changes with the temperature T1, it means that the coolant in the machine body 20 has entered the first radiator 40, and the thermostat 30 has been turned on. ΔT=T1-T2, and the value of ΔT can be used to determine whether the flow of the coolant entering the first radiator 40 is normal. If the relationship ΔT≤a is satisfied, it is determined that the flow entering the first radiator 40 is normal, indicating that the internal valve of the thermostat 30 is opened normally, and the thermostat 30 has no faults.

[0068] If the relational expression △T≤a is not satisfied, that is, △T>a, the temperature T3 of the third sensor 63 is obtained, and whether the thermostat 30 is faulty is determined based on whether the relational expression T3≤b is satisfied. Wherein, b is the second threshold value, which is a preset temperature determined by experiments, that is, the normal temperature of the warm air supplied by the second radiator 50 measured when the engine is normal, and the unit of b is Celsius (℃).

[0069] Specifically, if the relationship △T≤a is not satisfied, that is, △T>a, the flow rate entering the first radiator 40 is insufficient. The reason for the insufficient flow rate entering the first radiator 40 may be insufficient opening of the internal valve of the thermostat 30, insufficient flow of the water pump 10, blockage of the channel of the first radiator 40, etc. The reason for the insufficient flow rate of the water pump 10 may be the presence of air at the water pump 10, a failure of the water pump 10, etc. The elimination method can be used to first determine whether the relationship △T≤a is not satisfied due to insufficient flow of the water pump 10, so as to narrow the judgment range, and then facilitate judgment on whether the opening of the internal valve of the thermostat 30 is insufficient, and thus judge whether the thermostat 30 is faulty.

[0070] When the flow rate of the water pump 10 is insufficient, the flow rate at the second radiator 50 is also lower than the normal value, and the medium temperature T3 after the heat exchange between the second radiator 50 and the outlet water of the body 20 is lower than the normal temperature, that is, the relationship T3≤b is satisfied, and it can be judged that the thermostat 30 is not faulty. If the relationship T3≤b is not satisfied, that is, T3>b, it means that the problem is not caused by insufficient flow rate of the water pump 10, but may be caused by insufficient opening of the internal valve of the thermostat 30, blockage of the channel of the first radiator 40, etc.

[0071] Combined with the aforementioned multiple reasons for not satisfying the relationship △T≤a, after excluding the reason of insufficient flow of the water pump 10, it may also be the reason of the channel blockage of the first radiator 40 and the failure of the thermostat 30. Specifically, judging whether the thermostat 30 is faulty according to whether the relationship T3≤b is satisfied includes:

[0072] If the relational expression T3≤b is not satisfied, it is determined whether the thermostat 30 is faulty according to the time A when the outlet water temperature T2 of the first radiator 40 starts to rise after the outlet water temperature T1 of the body 20 reaches the target temperature d.

[0073] If the relationship T3≤b is not satisfied, that is, T3>b, after excluding the problem of water pump 10 failure, the second factor to be considered is that the channel of the first radiator 40 is blocked, and most of the high-temperature coolant at the water outlet of the body 20 flows to the second radiator 50, causing the temperature of the second radiator 50 to be higher than the normal temperature; when the channel of the first radiator 40 is blocked, since the temperature T2 changes with the temperature T1, the coolant can still flow to the second sensor 62 through the channel of the first radiator 40, but the coolant can only flow slowly from the water inlet to the water outlet of the first radiator 40 at a very small flow rate. In this embodiment, the timing starts after the temperature T1 reaches the target temperature d, and the timing ends when the temperature T2 starts to rise. According to the length of this period A, it can be determined whether the thermostat 30 is faulty or the channel of the first radiator 40 is blocked.

[0074] Specifically, judging whether the thermostat 30 is faulty according to the start time A of the rise of the outlet water temperature T2 of the first radiator 40 after the outlet water temperature T1 of the body 20 reaches the target temperature d includes:

[0075] If A≤H is satisfied, it is determined that T3>b is caused by the blockage of the channel of the first radiator 40, and the thermostat 30 is not faulty. Among them, H refers to the longest time required for the thermostat 30 to open normally, that is, when the electronic control opening and mechanical opening functions of the thermostat 30 are normal, the time required for the thermostat 30 to open, the unit is second (s), for example, 10s. The time H is determined by experimental testing. When A≤H is satisfied, the second sensor 62 can measure the temperature T2 starting to rise in a very short time, indicating that the thermostat 30 is opened normally without fault, and then it is determined that the channel of the first radiator 40 is blocked, which causes the relationship T3≤b not to be satisfied.

[0076] If H<A≤I, or A>J is satisfied, the thermostat 30 is judged to be faulty. Wherein, I refers to the shortest time required for the thermostat 30 to be opened only by the mechanical module, that is, the thermostat 30 has no electronic control opening function, and the shortest time required for pure mechanical opening, and the unit of I is seconds (s), for example, 200s. J refers to the longest time required for the thermostat 30 to be opened only by the mechanical module, that is, the longest time required for pure mechanical opening without the electronic control opening function, and the unit of J is seconds (s), for example, 300s. The times I and J are determined by experimental tests. The times H, I, and J satisfy: H<I<J.

[0077] When H<A≤I is satisfied, the opening time of the thermostat 30 becomes longer. At this time, both the electronic control opening function and the mechanical opening function of the thermostat 30 participate in opening the internal valve, and the performance of the electronic control module of the thermostat 30 is attenuated. When the performance of the electronic control module of the thermostat 30 is attenuated, it is manifested as a slow melting speed of the wax package, insufficient opening sensitivity and opening lift of the internal valve, resulting in the opening time of the internal valve being slower than the normal time H, which in turn causes the time A to also become slower, and it can be determined that the thermostat 30 is faulty.

[0078] When A>J is satisfied, it indicates that both the electronic control module and the mechanical module of the thermostat 30 are failed, resulting in a longer opening time, and it can be determined that the thermostat 30 is faulty.

[0079] If I<A≤J is satisfied, it indicates that the mechanical module of the thermostat 30 is normal and the electronic control module is failed, and only the mechanical module can be used for purely mechanical opening.

[0080] When the electronic control module of the thermostat 30 fails, the possible reason is that the control circuit of the electronic control module of the thermostat 30 itself fails or there is a problem with the external control circuit of the thermostat 30. Then, whether the thermostat 30 is faulty is determined based on whether the relationship e≤R≤f is satisfied; wherein R is the resistance value of the electronic control module of the thermostat 30, e and f are both preset resistance fluctuation values, e and f are determined through experimental tests, and e<f.

[0081] When the relationship e≤R≤f is satisfied, it indicates that the resistance value of the thermostat 30 is within the standard resistance range, and the control circuit of the electric control module of the thermostat 30 is invalid.

[0082] When the relationship e≤R≤f is not satisfied, that is, R<e or R>f, it means that the resistance value of the thermostat 30 is not within the standard resistance range, the resistance of the electric control module fails, and the thermostat 30 is faulty.

[0083] In the case of determining that the electric control module of the thermostat 30 is not failed, when the relationship e≤R≤f is satisfied, it can be determined that the control circuit of the electric control module of the thermostat 30 is not faulty, and the cause of the fault is an external control circuit fault.

[0084] If temperature T2 does not change with temperature T1, there is another situation that there is a large amount of air at the thermostat 30. Due to the presence of air, the coolant is separated by the air and it is difficult to contact the wax bag well, resulting in the wax bag being unable to be melted, and then making it difficult for the internal valve of the thermostat 30 to open normally. Therefore, this factor needs to be taken into consideration.

[0085] Specifically, judging whether the thermostat 30 is faulty according to whether the outlet water temperature T2 of the first radiator 40 follows the outlet water temperature T1 of the body 20, further includes:

[0086] If the outlet water temperature T2 of the first radiator 40 does not change with the outlet water temperature T1 of the body 20 , it is determined whether the thermostat 30 is faulty based on whether the outlet water temperature T2 of the first radiator 40 changes with the outlet water temperature T1 of the body 20 after the thermostat 30 is exhausted.

[0087] In other words, since there is a factor that the temperature T2 does not change with the temperature T1 due to the presence of a large amount of air at the thermostat 30, the thermostat 30 can be vented before verification, and the venting method can be solved by re-vacuuming the coolant or disassembling the thermostat 30 or disassembling the normally connected small circulation pipeline on the thermostat 30. For details, please refer to the relevant content in the prior art, which will not be elaborated here.

[0088] Further, judging whether the thermostat 30 is faulty is performed according to whether the outlet water temperature T2 of the first radiator 40 changes with the outlet water temperature T1 of the body 20 after the thermostat 30 is exhausted, including:

[0089] If the outlet water temperature T2 of the first radiator 40 changes with the outlet water temperature T1 of the housing 20 , it is determined whether the thermostat 30 is faulty based on whether the relationship ΔT≤a is satisfied.

[0090] If the outlet water temperature T2 of the first radiator 40 does not change with the outlet water temperature T1 of the housing 20 , it is determined that the thermostat 30 is faulty.

[0091] Specifically, after the thermostat 30 is vented, verification is performed and the aforementioned determination method is continued to be performed to determine whether the thermostat 30 is faulty.

[0092] Based on the above judgment process, when the diagnosis result of the thermostat 30 fault diagnosis method is that the thermostat 30 is faulty, there are the following situations.

[0093] 1. If the outlet water temperature T2 of the first radiator 40 changes with the outlet water temperature T1 of the body 20 within a predetermined time, and ΔT>a, T3>b, A>H, then the result of the thermostat 30 failure is output. The predetermined time is greater than or equal to J.

[0094] 2. If the outlet water temperature T2 of the first radiator 40 changes with the outlet water temperature T1 of the body 20 , and ΔT>a, T3>b, and H<A≤I, the performance of the electronic control module of the output thermostat 30 is degraded.

[0095] 3. If the outlet water temperature T2 of the first radiator 40 changes with the outlet water temperature T1 of the body 20 within a predetermined time, and ΔT>a, T3>b, A>H, and A>I, then the result of the failure of the electronic control module of the thermostat 30 is output. The predetermined time is greater than or equal to J.

[0096] 4. If the outlet water temperature T2 of the first radiator 40 changes with the outlet water temperature T1 of the body 20 within a predetermined time, and ΔT>a, T3>b, A>H, and I<A≤J, then the result of outputting that the mechanical module of the thermostat 30 is normal and the electronic control module is inoperative is obtained. The predetermined time is greater than or equal to J.

[0097] 5. If the outlet water temperature T2 of the first radiator 40 changes with the outlet water temperature T1 of the body 20 within a predetermined time, and ΔT>a, T3>b, A>H, and A>J, then the mechanical module and the electronic control module of the output thermostat 30 are both failed. The predetermined time is greater than or equal to J.

[0098] 6. When the result of the failure of the electronic control module is output, if e≤R≤f, the result of the failure of the control circuit of the electronic control module is further output.

[0099] 7. When outputting the result of the failure of the electronic control module, if R<e or R>f, then further outputting the result of the failure of the resistance of the electronic control module.

[0100] 8. If the outlet water temperature T2 of the first radiator 40 does not change with the outlet water temperature T1 of the body 20 within a predetermined time, the result of the thermostat 30 failure is output.

[0101] In the description of the embodiments of the present application, it should be noted that the orientation or positional relationship of terms such as "center", "up", "down", "left", "right", "vertical", "horizontal", "inside" and "outside" are based on the orientation or positional relationship described in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0102] What is disclosed above is only a preferred embodiment of the present application, and it certainly cannot be used to limit the scope of rights of the present application. Ordinary technicians in this field can understand that all or part of the processes of implementing the above embodiment and equivalent changes made according to the claims of the present application are still within the scope covered by the present application.

Claims

1. A thermostat fault diagnosis method, characterized in that: The thermostat fault diagnosis method is used for an engine, the engine comprising a water pump, a body, a thermostat, a first radiator and a second radiator, the body being in communication with a water outlet of the water pump, the thermostat and the second radiator being in communication with the water outlet of the body respectively, the first radiator being in communication with the water outlet of the thermostat, the water outlet of the first radiator being in communication with a water inlet of the water pump, and the water outlet of the second radiator being in communication with a water inlet of the water pump; The thermostat fault diagnosis method comprises: When the outlet water temperature T1 of the machine body is greater than a predetermined value, the thermostat is judged to be faulty according to the outlet water temperature T1 of the machine body, the outlet water temperature T2 of the first radiator, and the medium temperature T3 after heat exchange between the second radiator and the outlet water of the machine body.

2. The thermostat fault diagnosis method according to claim 1, characterized in that: include: If the outlet water temperature T2 of the first radiator changes with the outlet water temperature T1 of the machine body within a predetermined time, and ΔT>a, T3>b, A>H, then the result of the thermostat failure is output; Among them, △T is the difference between the water outlet temperature T1 of the body and the water outlet temperature T2 of the first radiator, a is the first threshold, b is the second threshold, A is the start time of the water outlet temperature T2 of the first radiator rising, and H is the maximum time required for the thermostat to open normally.

3. The thermostat fault diagnosis method according to claim 2, characterized in that: The thermostat is an electronic thermostat, and the thermostat comprises a mechanical module and an electric control module; If the outlet water temperature T2 of the first radiator changes with the outlet water temperature T1 of the body, and ΔT>a, T3>b, and H<A≤I, then the result of the performance attenuation of the electronic control module of the thermostat is output; Wherein, I is the shortest time required for the thermostat to be turned on only by the mechanical module.

4. The thermostat fault diagnosis method according to claim 2, characterized in that: The thermostat is an electronic thermostat, and the thermostat comprises a mechanical module and an electric control module; If the outlet water temperature T2 of the first radiator changes with the outlet water temperature T1 of the body within a predetermined time, and ΔT>a, T3>b, A>H, and A>I, then the result that the electronic control module of the thermostat is failed is output; Wherein, I is the shortest time required for the thermostat to be turned on only by the mechanical module.

5. The thermostat fault diagnosis method according to claim 2, characterized in that: The thermostat is an electronic thermostat, and the thermostat comprises a mechanical module and an electric control module; If the outlet water temperature T2 of the first radiator changes with the outlet water temperature T1 of the body within a predetermined time, and ΔT>a, T3>b, A>H, and I<A≤J, then the result that the mechanical module of the thermostat is normal and the electronic control module is failed is output; Wherein, I is the shortest time required for the thermostat to be turned on only by the mechanical module, and J is the longest time required for the thermostat to be turned on only by the mechanical module.

6. The thermostat fault diagnosis method according to claim 2, characterized in that: If the outlet water temperature T2 of the first radiator changes with the outlet water temperature T1 of the body within a predetermined time, and ΔT>a, T3>b, A>H, and A>J, then the result that both the mechanical module and the electronic control module of the thermostat are failed is output; Wherein, J is the maximum time required for the thermostat to be turned on only by the mechanical module.

7. The thermostat fault diagnosis method according to any one of claims 4 to 6, characterized in that: When outputting the result of the failure of the electronic control module, if e≤R≤f, further outputting the result of the failure of the control circuit of the electronic control module; Wherein, R is the resistance value of the electronic control module of the thermostat, and e and f are both preset resistance fluctuation values.

8. The thermostat fault diagnosis method according to any one of claims 4 to 6, characterized in that: When outputting the result of the failure of the electric control module, if R<e or R>f, further outputting the result of the resistance failure of the electric control module; Wherein, R is the resistance value of the electronic control module of the thermostat, and e and f are both preset resistance fluctuation values.

9. The thermostat fault diagnosis method according to claim 1, characterized in that: include: If the outlet water temperature T2 of the first radiator does not change with the outlet water temperature T1 of the machine body within a predetermined time, the result of the thermostat failure is output.

10. A thermostat fault diagnosis device, characterized in that: The method comprises a memory and a processor, wherein the memory stores a computer program, and the processor is used to execute the computer program to implement the thermostat fault diagnosis method according to any one of claims 1 to 9.

11. An engine, characterized in that: The engine comprises a water pump, a body, a thermostat, a first radiator and a second radiator, the body is communicated with a water outlet of the water pump, the thermostat and the second radiator are respectively communicated with the water outlet of the body, the first radiator is communicated with the water outlet of the thermostat, the water outlet of the first radiator is communicated with the water inlet of the water pump, and the water outlet of the second radiator is communicated with the water inlet of the water pump; The engine diagnoses faults using the thermostat fault diagnosis method according to any one of claims 1 to 9.

12. A vehicle, characterized in that: Comprising the engine as claimed in claim 11.

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