KR100285266B1 - Alarm system for thermostat trouble for vehicle - Google Patents

Abstract

PURPOSE: A thermostat trouble alarm system for vehicles is provided to detect any trouble of a thermostat by comparing the water temperatures with a water jacket and an upper channel while alarming an operator with the trouble. CONSTITUTION: The first cooling water temperature sensor(210) is mounted to a thermostat for detecting the temperature of cooling water on the water jacket side. The second cooling water temperature sensor(220) is installed in an upper channel for detecting the temperature of cooling water within the upper channel. An alarm display unit(230) is mounted to an instrument panel and energized by a battery. A switching unit(240) is on/off controlled via an operation control signal, and if turned on, electrically connects between the battery and the alarm display unit(230). An ECU(250) compares detection signals from the temperature sensors(210,220), and if the cooling water temperature from the second temperature sensor(220) rises or descends beyond a certain range when the cooling water temperature from the first temperature sensor(210) is beyond a specific temperature range for turning off the thermostat, decides that the thermostat has a trouble to turn on the switching unit(240).

Description

Warning system of malfunction of thermostat in car

The present invention relates to a failure warning system of a thermostat of an automobile, and in particular, by detecting and comparing water temperatures inside a water jacket and an inside of a radiator upper flow path, respectively, to detect a failure of the thermostat, and to the driver when the thermostat is broken. It is about the thermostat failure warning system of the vehicle which gives a warning.

In general, a cooling device is a device for cooling an engine to prevent overheating and maintaining it at an appropriate temperature. There are an air cooling type that directly cools the outside of the engine using outside air and a water cooling type that circulates and cools the cooling water inside the engine.

As shown in FIG. 1, the water-cooled cooling apparatus includes a water jacket 30 surrounding the cylinder 10 and the combustion chamber 20, a water pump 40 for pumping and circulating water into the cylinder 10, and a high temperature of cooling water. It consists of a radiator (50) for transferring heat to the outside air to cool, a fan (60) for helping the radiator (50) to ventilate, and a thermostat (100) for quickly raising the coolant to an appropriate temperature immediately after starting. The coolant is circulated inside the water jacket 30 surrounding the cylinder 10 by 40 to cool the heat generated in the cylinder block 70 and the cylinder head 80, and then the water jacket 30. The coolant warmed from the radiator 50 to draw heat radiation. Then, the water radiated from the radiator 50 is circulated back to the water jacket 30 to cool the engine.

In addition, the fan is forced to contact the radiator 50 to the outside air to improve the heat dissipation effect, and the upper flow path 90 between the water jacket 30 and the radiator 50 automatically according to the change of the temperature of the coolant By controlling the opening and closing to control the flow rate flowing to the radiator 50, the thermostat 100 which maintains the temperature of cooling water at the appropriate temperature is provided, and the circulation path of a cooling water is changed according to temperature.

The operation of the thermostat will be described in more detail below with reference to FIGS. 2A and 2B.

2A is a cross-sectional view showing a state when the thermostat is closed, and FIG. 2B is a cross-sectional view showing a state when the temperature of the coolant inside the water jacket is increased to open the thermostat.

As shown in FIG. 2A, when the temperature of the coolant inside the water jacket rises above the prescribed temperature in the state in which the valve 110 is closed, the wax 125 in the pallet 120 expands to the inside of the pallet 120. By compressing the inserted rubber 130, the spindle 140 in the center of the rubber 130 is pressed upward, but the spindle 140 is mounted on the bracket 150, so the pallet 120 is fixed It descends and the valve 110 opens as shown in FIG. 2B.

On the other hand, as shown in FIG. 2B, when the valve 110 is opened and the hot coolant of the water jacket circulates to the radiator, and the temperature of the coolant is lowered, the expanded wax 125 is contracted and the rubber 130 is compressed. The pallet 120 is removed and is returned to its original position as shown in FIG. 2A by the elasticity of the spring 160.

However, the water jacket warmed by the heat generated from the engine when the thermostat fails and the valve is kept closed even when the valve is opened above a certain temperature, that is, when the valve to be opened at 88 ° C is closed even at a temperature above 88 ° C. As the coolant inside is not cooled and the engine is overheated, the cylinder is deformed or the oil film on the cylinder wall is broken, resulting in poor lubrication. Also, the combustion condition worsens, leading to knocking or premature ignition. do. In addition, when the coolant is overheated, the coolant turns into water vapor and raises the pressure inside the radiator. Thus, the increased pressure acts on the radiator cap, causing the radiator cap to open upward, thereby rapidly discharging water vapor through the radiator cap while driving. This is generated to generate a concentration on the driver's driving.

On the other hand, when the thermostat fails and the valve is opened even below a predetermined temperature, the coolant continues to cool through the radiator, so that the amount of heat lost by cooling increases due to combustion, which reduces the engine's thermal efficiency. The ECU, which controls the fuel injection amount based on the coolant temperature, increases the fuel consumption by increasing the fuel injection amount because the coolant temperature is low, and dilutes the engine oil by the gasoline because the insufficiency of gasoline in the cylinder is supplied. It is a cause of making and accelerating wear of the cylinder. In addition, the water temperature is always low, resulting in a decrease in the performance of the air conditioner.

An object of the present invention for removing the above problems is to detect and compare the water temperature inside the water jacket and the inside of the radiator upper flow path, respectively, to detect the failure of the thermostat, and to warn the driver if the thermostat is broken To provide a thermostat failure warning system for a car.

1 is a cross-sectional view showing an embodiment of a conventional water-cooled cooling device.

Figure 2a is a sectional view showing a state in which the thermostat is closed.

2B is a sectional view showing a state in which the thermostat is open;

Figure 3 is a block diagram showing the configuration of a failure warning system of the thermostat according to the present invention.

4 is a flow chart showing the operation of the thermostat failure warning system of FIG.

* Description of the symbols for the main parts of the drawings *

100: thermostat 210: second coolant temperature sensor

220: second coolant temperature sensor 230: warning buzzer

240: switching means 250: ECU

LY: relay switch

Features of the present invention for achieving the above object is provided with a thermostat 100 for controlling the opening and closing of the flow path formed between the water jacket and the radiator, and the ignition switch (IG) is connected to one end of the battery to start the vehicle In one vehicle, a first coolant temperature sensor 210 mounted on the thermostat 100 to detect the coolant temperature inside the water jacket and a radiator installed on the middle of the upper radiator to detect the temperature of the coolant inside the upper flow path. 2, the coolant temperature sensor 220, a warning display unit 230 mounted on a predetermined portion of the instrument panel inside the vehicle and operated by power supplied from a battery, and on / off are controlled by an input operation control signal, In this case, the switching unit 240 forms a flow path of the current between the battery and the warning display unit 230, and the plurality of coolant temperature sensors 21. The second coolant temperature sensor 220 when the coolant temperature detected from the first coolant temperature sensor 210 is outside the temperature range in which the valve of the thermostat 100 is opened by comparing the signals detected from 0) 220. It is included in the ECU 250 to turn on the switching unit 240 is determined as a failure when the coolant temperature detected from the rise or fall over a predetermined range.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

3 is a view showing a thermostat failure warning system according to the present invention.

The thermostat failure warning system is installed in the thermostat 100 to detect the coolant temperature on the water jacket side, and a first coolant temperature sensor 210 and a radiator installed in the middle of the upper flow path to detect the temperature of the coolant inside the upper flow path. The second cooling water temperature sensor 220 is mounted to a predetermined portion of the instrument panel inside the vehicle, and one end is electrically connected to an ignition switch IG for transmitting power output from the battery V and output from the battery V. A warning display unit 230 for informing the failure of the thermostat 100 by operating by a power supply, and the on / off is controlled by the input operation control signal, the current between the ignition switch (IG) and the warning display unit 230 Compares the signals detected by the switching unit 240 to control the flow path of the plurality of coolant temperature sensors 210 and 220 and accordingly the switch Includes; (250 Engine Control Unit) ECU which outputs the operation control signal for controlling on / off of the section 240.

Meanwhile, in the embodiment of the present invention, the switching unit 240 preferably uses the base terminal B as a control terminal connected to the output terminal of the ECU 250, and the output terminal is an emitter ground that is a collector terminal C. The transistor Tr and the contact point are located at a link between the ignition switch IG and the warning display unit 230, and a coil controlling the on / off of the contact point is connected to the output terminal C of the transistor Tr. And a relay switch LY, and when the high signal is output from the ECU 250, the transistor 240 is turned on so that the contact of the relay switch LY is turned on. A flow path of current between 230 is formed.

In addition, the warning display unit 230 uses a warning buzzer or a warning light that lights up.

The operation of the thermostat failure warning system having the above-described configuration will be described in detail below with reference to FIG. 4.

When the user starts the vehicle using the car key, the ignition switch IG is turned on, and the current output from the battery V is transmitted to the one end of the relay switch LY via the ignition switch IG. As the engine starts, the coolant temperature inside the water jacket increases.

Meanwhile, the ECU 250 operates the plurality of coolant temperature sensors 210 and 220 to detect the coolant temperature A inside the water jacket and the coolant temperature B inside the radiator upper flow path. 1 It is determined whether the coolant temperature A detected by the coolant temperature sensor 210 is equal to or less than a specific temperature range X in which the valve is opened (S102).

If the coolant temperature A detected from the first coolant temperature sensor 210 in the step S102 is less than or equal to a specific temperature range X, the coolant temperature B detected from the second coolant temperature sensor 220 is in a predetermined range (external air). It is determined whether the cooling water temperature rises by more than a range (S103), the determination process (S103) is the reason why the thermostat (100) inside the water jacket when opened at a temperature lower than the temperature that must be opened after a failure This is because the warmed coolant flows into the radiator upper flow path, so that the coolant having a low temperature inside the radiator upper flow path is mixed with the warmed coolant flowing from the water jacket and the coolant temperature B inside the radiator upper flow path increases.

Therefore, when it is determined in step S103 that the coolant temperature B detected from the second coolant temperature sensor 220 rises by a predetermined range or more, the ECU 250 determines that the predetermined size is set as the base B of the transistor Tr. By outputting a high signal, the transistor Tr is energized, which causes a current to be applied to the coil constituting the relay switch LY, thereby closing the contact. Thus, the ignition switch IG and the warning display unit 230. The flow path of the current is formed between the warning display unit 230 is to operate (S104).

On the other hand, when the coolant temperature A detected from the first coolant temperature sensor 210 in step S102 is not equal to or less than the specific temperature range X, the coolant temperature A detected from the first coolant temperature sensor 210 is specified. It is determined whether or not the temperature range (X) or more (S105), and when the coolant temperature (A) is more than the specific temperature range (X), the ECU 250 determines the coolant temperature (B) detected from the second coolant temperature sensor 220. Is determined whether the temperature rises above a predetermined range (the range in which the coolant temperature is variable by outside air) (S106), and the reason for the determination process (S106) is that when the thermostat 100 fails and does not open at a temperature to be opened. This is because the temperature B of the coolant inside the radiator upper flow path does not rise because the coolant warmed inside the water jacket does not flow into the radiator upper flow path.

Therefore, if the coolant temperature B detected from the second coolant temperature sensor 220 in step S106 does not rise above a certain range, the ECU 250 outputs a high signal to the base B of the transistor Tr, As described above, the warning display unit 230 is operated.

Therefore, according to the present invention, the ECU 250 detects the failure of the thermostat 100 and informs the user of the failure.

According to the present invention operated as described above, the ECU detects the failure of the thermostat and informs the user of the failure, so that the engine is not overheated and thus the deformation of the cylinder head and the cylinder block can be prevented. In addition to being able to maintain and prevent fuel economy from falling, cold start does not occur and thus generation of soot is suppressed.

Claims (2)

In a motor vehicle having a thermostat 100 for controlling opening and closing of a flow path formed between a water jacket and an upper part of a radiator, and an ignition switch IG for connecting one end of the battery to start the vehicle, the thermostat 100 A first coolant temperature sensor (210) mounted to the coolant and detecting the coolant temperature on the water jacket side; A second coolant temperature sensor 220 installed in the middle of the upper radiator to detect a temperature of the coolant at the upper flow path nap; A warning display unit 230 mounted to a predetermined portion of the instrument panel inside the vehicle and operated by power supplied from a battery; A switching unit 240 configured to control on / off by an input operation control signal and to form a flow path of a current between the ignition switch IG and the warning display unit 230 only when it is turned on; When the coolant temperature detected by the first coolant temperature sensor 210 is compared to a signal detected by the plurality of coolant temperature sensors 210 and 220, the temperature of the coolant temperature sensor 210 is outside a specific temperature range in which the valve of the thermostat 100 is opened. Thermostat failure characterized in that it comprises an ECU (250) to turn on the switching unit 240 is determined as a failure when the coolant temperature detected from the second coolant temperature sensor 220 rises or falls over a predetermined range. Warning system. The method of claim 1, wherein the switching unit 240 is an emitter ground type transistor (Tr) is connected to the base terminal (B) of the control terminal is connected to the output terminal of the ECU 250 and the output terminal is a collector terminal (C), The contact is located at the link between the ignition switch IG and the warning display 230 and the coil controlling the on / off of the contact is a relay switch LY connected to the output terminal C of the transistor Tr. Thermostat failure warning system, characterized in that configured.

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