JP2015094332A - Engine cooling system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inhibit an engine from reaching a high temperature.SOLUTION: When the state where an engine outlet water temperature Twe as a cooling water temperature near an engine outlet in a circulation flow path is lower than a radiator inlet water temperature Twr as a cooling water temperature near a radiator inlet in the circulation flow path continues for a predetermined time, a predetermined mark is shown on a display to inform an occupant that air resides. Thus, the occupant who is informed that the air resides near the installation site of a water temperature sensor can be urged to cope therewith, so that the engine can be inhibited from reaching a high temperature.

Description

  The present invention relates to an engine cooling device, and more specifically, a circulation flow path for circulating cooling water between an engine and a radiator, and a cooling water temperature near the engine cooling water outlet attached to the circulation flow path near the engine cooling water outlet. An engine outlet water temperature sensor for detecting the engine outlet water temperature, a radiator inlet water temperature sensor for detecting a radiator inlet water temperature, which is a cooling water temperature mounted near the cooling water inlet of the radiator in the circulation flow path, and The present invention relates to an engine cooling apparatus.

  Conventionally, this type of engine cooling device includes a circulation path through which engine cooling water circulates, a radiator provided in the circulation flow path, and a flow rate control valve that adjusts the flow rate of cooling water to the radiator. It has been proposed (see, for example, Patent Document 1). In this device, when the engine outlet water temperature is equal to or higher than the predetermined reference temperature and the radiator outlet water temperature is equal to or lower than the predetermined reference temperature, the flow control valve is fully opened so that the flow of cooling water between the engine and the radiator becomes maximum. To do. Then, when the engine outlet water temperature does not decrease thereafter, the engine is prevented from reaching a high temperature by increasing the fuel injection amount of the engine.

JP 2006-105105 A

  In the engine cooling device described above, if air stays in the vicinity of the water temperature sensor for detecting the engine outlet water temperature in the circulation flow path, the water temperature sensor detects the temperature of the air as the engine outlet water temperature. Since the air temperature is lower than the actual engine temperature, if the engine cooling is controlled using the engine outlet water temperature detected when the air remains, the engine may not be properly cooled and the engine may reach a high temperature. . Therefore, in order to prevent the engine from reaching a high temperature, it is desired to notify the occupant that the air has accumulated and to take some measures.

  The engine cooling device of the present invention is mainly intended to notify an occupant that air is retained in the cooling water circulation passage.

  The engine cooling device of the present invention employs the following means in order to achieve the above-mentioned main object.

The engine cooling device of the present invention comprises:
A circulation passage for circulating cooling water between the engine and the radiator, and an engine outlet for detecting an engine outlet water temperature, which is attached to the circulation passage near the cooling water outlet of the engine and is a cooling water temperature near the cooling water outlet of the engine A cooling device for an engine comprising: a water temperature sensor; and a radiator inlet water temperature sensor that is attached to the circulation passage near the cooling water inlet of the radiator and detects a radiator inlet water temperature that is a cooling water temperature near the cooling water inlet of the radiator. There,
When the state where the engine outlet water temperature is lower than the radiator inlet water temperature continues, a warning means for issuing a warning is provided.

  In the engine cooling device of the present invention, an engine outlet water temperature sensor that is mounted near the engine coolant outlet in the circulation channel and detects the engine outlet water temperature that is the coolant temperature near the engine coolant outlet, and the circulation channel A cooling device for an engine having a radiator inlet water temperature sensor that detects a radiator inlet water temperature that is mounted near the radiator cooling water inlet and detects a radiator inlet water temperature that is a cooling water temperature near the radiator cooling water inlet, wherein the engine outlet water temperature is lower than the radiator inlet water temperature. A warning will be issued when this continues. Accordingly, it is possible to notify the occupant that the air is staying in the circulation flow path and prompt some action.

It is a block diagram which shows the outline of a structure of the cooling device 20 as one Example of this invention. It is explanatory drawing for demonstrating the attachment position of the water temperature sensor 34a. It is explanatory drawing which shows an example of the time change of the engine outlet water temperature Twe and the radiator inlet water temperature Twr when the thermostat 44 is normal. It is explanatory drawing which shows an example of the time change of the engine outlet water temperature Twe and the radiator inlet water temperature Twr when the opening abnormality which the thermostat 44 does not close in the fully open state has arisen. It is explanatory drawing which shows an example of the time change of the engine exit water temperature Twe and the radiator inlet water temperature Twr when the air is not staying in the vicinity of the attachment position of the water temperature sensor 34a of the circulation flow path 34. It is explanatory drawing which shows an example of the time change of the engine outlet water temperature Twe and the radiator inlet water temperature Twr when air is staying in the vicinity of the attachment position of the water temperature sensor 34a in the circulation flow path 34.

  Next, the form for implementing this invention is demonstrated using an Example.

  FIG. 1 is a configuration diagram showing an outline of the configuration of a cooling device 20 as an embodiment of the present invention, and FIG. 2 is an explanatory diagram for explaining a mounting position of a water temperature sensor 34a. The cooling device 20 according to the embodiment is mounted on a vehicle on which the engine 22 is mounted. The cooling device 20 cools the exhaust gas supplied to an EGR device that recirculates the cooling water to the intake side and a circulation passage 26 that circulates the cooling water to the radiator 24 that cools the cooling water as a cooling medium by the engine 22 and outside air. The EGR cooler 30, the engine 22 and the throttle valve 32 for circulating the coolant water 34 circulate, and the engine 22 and the exhaust gas for exchanging heat by branching a part of the coolant circulating in the EGR cooler 30. A circulation channel 40 that circulates the heat recovery unit 36 and the air in the passenger compartment to the heater core 38 for warming with the cooling water and then returns to the circulation channel 34 and the cooling water to the circulation channel 26 according to the temperature of the cooling water. A thermostat 44 for switching whether or not to circulate, an electric water pump 46 for pumping cooling water from the thermostat 44 to the engine 22, and various information A display 48 capable of displaying, and a control unit 50 for controlling the whole.

  Although not shown, the control device 50 is configured as a microcomputer centered on a CPU, and includes a ROM for storing processing programs, a RAM for temporarily storing data, an input / output port, a communication port, and the like. The control device 50 includes a radiator inlet water temperature Twr from a water temperature sensor 26 a that detects the temperature of the cooling water that is attached near the cooling water inlet of the radiator 24 in the circulation channel 26 and flows into the radiator 24, and the cooling water from the engine 22. The engine outlet water temperature Twe is input from the water temperature sensor 34a that detects the temperature of the engine. Further, the control device 50 outputs a drive signal to the electric water pump 46 that is driven and controlled according to the engine outlet water temperature Twe, an image signal to the display 48, and the like. As shown in FIG. 2, the water temperature sensor 34a is attached to the vicinity of the cooling water outlet of the engine 22 in the circulation channel 34 provided in the upper part of the engine 22 (the upper part of the engine head). .

  In the cooling device 20 of the embodiment, abnormality of the thermostat 44 is detected using the engine outlet water temperature Twe and the radiator inlet water temperature Twr. FIG. 3 is an explanatory diagram showing an example of temporal changes in the engine outlet water temperature Twe and the radiator inlet water temperature Twr when the thermostat 44 is normal, and FIG. 4 is when an opening abnormality occurs in which the thermostat 44 does not close in the fully open state. It is explanatory drawing which shows an example of the time change of engine outlet water temperature Twe and radiator inlet water temperature Twr. When the thermostat 44 is normal, as shown in FIG. 3, when the temperature of the cooling water is low and the thermostat 44 is closed, the cooling water does not flow to the radiator 24 side, and therefore, between the engine outlet water temperature Twe and the radiator inlet water temperature Twr. When the temperature of the cooling water rises and the thermostat 44 is opened, the cooling water flows to the radiator 24 side, so that there is no difference between the engine outlet water temperature Twe and the radiator inlet water temperature Twr. On the other hand, when the opening abnormality occurs in the thermostat 44, as shown in FIG. 4, since the thermostat 44 is open even when the temperature of the cooling water is low, the cooling water flows to the radiator 24 side and the engine outlet water temperature There is no difference between Twe and the radiator inlet water temperature Twr. Thus, abnormality of the thermostat 44 can be detected by using the engine outlet water temperature Twe and the radiator inlet water temperature Twr.

  Next, in the cooling device 20 according to the embodiment configured as described above, an operation when air stays in the circulation flow path 34 will be described. In the cooling device 20 of the embodiment, the water temperature sensor 34a is attached in the vicinity of the cooling water outlet of the circulation channel 34 provided in the upper part of the engine 22 (the upper part of the engine head). Air is likely to stay near the attachment position of the sensor 34a. If air stays in the vicinity of the attachment position of the water temperature sensor 34a in the circulation channel 34, the water temperature sensor 34a detects the temperature of the air as the engine outlet water temperature Twe. Since the temperature of the air is lower than the actual temperature of the engine 22, the engine 22 can be properly cooled by driving the electric water pump 46 using the engine outlet water temperature Twe detected in a state where the air is accumulated to cool the engine 22. There may be a problem that the engine 22 becomes hot and the temperature becomes high. In order to avoid such an inconvenience, the stagnation of air near the attachment position of the water temperature sensor 34a in the circulation flow path 34 is detected using the engine outlet water temperature Twe and the radiator inlet water temperature Twr.

  FIG. 5 is an explanatory diagram showing an example of temporal changes in the engine outlet water temperature Twe and the radiator inlet water temperature Twr when air is not staying near the position where the water temperature sensor 34a of the circulation channel 34 is attached. FIG. It is explanatory drawing which shows an example of the time change of the engine outlet water temperature Twe and the radiator inlet water temperature Twr when air is staying in the vicinity of the attachment position of the water temperature sensor 34a of the path 34. When air is not staying, the water temperature sensor 34a is closer to the engine 22 than the water temperature sensor 26a. Therefore, as shown in FIG. 5, the engine outlet water temperature Twe tends to be higher than the radiator inlet water temperature Twr. is there. On the other hand, when the air stays, the water temperature sensor 34a detects the air temperature as the engine outlet water temperature Twe. Therefore, the radiator inlet water temperature Twr tends to be higher than the engine outlet water temperature Twe. In the control device 50 of the cooling device 20 of the embodiment, when the state where the radiator inlet water temperature Twr is higher than the engine outlet water temperature Twe continues for a predetermined time tref (for example, 10 sec, 15 sec, 20 sec, etc.), It is determined that air is staying in the vicinity of the mounting position of the water temperature sensor 34a, and a predetermined mark is displayed on the display 48 to inform the occupant that air is staying. Accordingly, it is possible to notify the occupant that the air is stagnating and to take some countermeasures, and to prevent the engine 22 from reaching a high temperature.

  In the cooling device 20 of the embodiment described above, when the state where the engine outlet water temperature Twe is lower than the radiator inlet water temperature Twr continues for a predetermined time tref, the occupant is notified on the display 48 that air is stagnating. By displaying the predetermined mark, the engine 22 can be prevented from reaching a high temperature.

 In the cooling device 20 of the embodiment, the water temperature sensor 34 a for detecting the temperature of the cooling water from the engine 22 is attached in the vicinity of the outlet of the engine 22 in the circulation channel 34, but the water temperature sensor 34 a is attached to the engine in the circulation channel 26. It is good also as what attaches to 22 exit vicinity.

  In the cooling device 20 of the embodiment, the predetermined mark is displayed on the display 48 when the engine outlet water temperature Twe continues to be lower than the radiator inlet water temperature Twr. However, the cooling device 20 is limited to the one that displays the predetermined mark. Instead, a message indicating that air is stagnating may be displayed on the display 48. Moreover, it is not limited to what displays on such a display 48, It is good also as what emits a warning sound.

  In the embodiment, the cooling device of the present invention is applied to a vehicle including an exhaust heat recovery device, but may be applied to a vehicle not including such an exhaust heat recovery device.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. In the embodiment, the engine 22 corresponds to the “engine”, the radiator 24 corresponds to the “radiator”, the circulation passages 26 and 34 correspond to the “circulation passage”, and the water temperature sensor 26 a corresponds to the “radiator inlet water temperature sensor”. The water temperature sensor 34a corresponds to an “engine outlet water temperature sensor”, and the display 48 and the control device 50 correspond to “warning means”.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is the same as that of the embodiment described in the column of means for solving the problem. Therefore, the elements of the invention described in the column of means for solving the problems are not limited. That is, the interpretation of the invention described in the column of means for solving the problems should be made based on the description of the column, and the examples are those of the invention described in the column of means for solving the problems. It is only a specific example.

  As mentioned above, although the form for implementing this invention was demonstrated using the Example, this invention is not limited at all to such an Example, In the range which does not deviate from the summary of this invention, it is with various forms. Of course, it can be implemented.

  The present invention can be used in the manufacturing industry of engine cooling devices.

  20 Cooling device, 22 Engine, 24 Radiator, 26, 34 Circulation flow path, 26a, 34a Water temperature sensor, 30 EGR cooler, 32 Throttle valve, 36 Exhaust heat recovery device, 38 Heater core, 40 Branch flow path, 44 Thermostat, 46 Electric Water pump, 48 displays, 50 controls.

Claims (1)

A circulation passage for circulating cooling water between the engine and the radiator, and an engine outlet for detecting an engine outlet water temperature, which is attached to the circulation passage near the cooling water outlet of the engine and is a cooling water temperature near the cooling water outlet of the engine A cooling device for an engine comprising: a water temperature sensor; and a radiator inlet water temperature sensor that is attached to the circulation passage near the cooling water inlet of the radiator and detects a radiator inlet water temperature that is a cooling water temperature near the cooling water inlet of the radiator. There,
A cooling device for an engine, comprising: warning means for issuing a warning when the engine outlet water temperature is continuously lower than the radiator inlet water temperature.

Images