JP2003262124A - Cooling-fan control device for engine - Google Patents

Abstract

(57) [Summary] [Purpose] In an engine cooling fan control device, when a vehicle speed state and an air conditioner operating state satisfy certain conditions, the operation of the cooling fan is stopped even in the air conditioner operating state. Another object of the present invention is to reduce the fuel consumption and improve the power performance of the engine. The vehicle speed detected by the vehicle speed detecting means is higher than a set vehicle speed in an operating state of the air conditioner, the condition that the evaporator temperature detected by the evaporator temperature detecting means is lower than the set evaporator temperature, and the condition detected by the engine water temperature detecting means. A control means is provided for stopping and controlling the operation of the cooling fan when all the conditions, that is, the condition that the temperature of the engine cooling water is lower than the set engine water temperature, are satisfied.

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a cooling fan control device for an engine, and more particularly to a cooling fan control device which does not affect the power performance of the engine or the cooling performance of an air conditioner. The present invention relates to an engine cooling fan control device for controlling the operation of the engine. 2. Description of the Related Art In a vehicle, an engine is mounted, and an air conditioner condenser of an air conditioner (air conditioner), an engine cooling radiator of the engine cooling device, and a cooling fan of the engine cooling device are sequentially arranged from the front side of the vehicle. And an engine cooling fan control device for controlling the operation of the cooling fan in accordance with the temperature state of the engine cooling water detected by the engine water temperature detecting means and the operating state of the air conditioner. As described above, when the cooling fan that cools the radiator of the engine cooling device is also used to cool the condenser for the air conditioner of the air conditioner, the cooling is performed regardless of the temperature of the engine cooling water during the operation of the air conditioner. The fan is running. [0003] Such an engine cooling fan control device is disclosed in, for example, JP-A-2000-108652, JP-A-2-24034, and JP-A-1997-19.
No. 567. JP 2000-108
No. 652 discloses switching the cooling fan on and off based on a set speed lower than that in the normal mode when the air conditioner is operated in the economy mode. Japanese Unexamined Utility Model Publication No. 2-24034 discloses a method of determining a control amount of a cooling fan according to a temperature state of engine cooling water and an engine speed state. JP 1
Japanese Patent Application Laid-Open No. 997-19567 controls the rotation of a cooling fan in accordance with the load of an air conditioner, and obtains necessary cooling performance when necessary. [0004] However, in a conventional cooling fan control device for an engine, a cooling fan for cooling a radiator of the engine cooling device is also used for cooling a condenser for an air conditioner of an air conditioner. In this case, when the air conditioner is operating, the cooling fan operates regardless of the temperature of the engine cooling water, so that energy is consumed by driving the fan motor of the cooling fan. Therefore, there is a disadvantage that the fuel consumption increases by the amount of the energy and the power performance of the engine also decreases. [0005] When a vehicle is running at a certain speed, the cooling fan is not required to be operated since the air conditioner condenser is cooled by the traveling wind. However, in such a case, the air conditioner condenser is supercooled by both the traveling wind and the operation of the cooling fan, and the air conditioner is repeatedly operated and stopped. For this reason, when the air conditioner is activated and stopped, vibrations are generated by the operation of starting and stopping the devices of the air conditioner, which causes inconvenience. In addition, when the outside air temperature is low, the stop time of the air conditioner becomes longer than the operation time, so that the dehumidification (defrost) performance of the air conditioner is reduced, and the dehumidification performance is lowered. However, there is an inconvenience that the fogging of the window glass is hardly removed and the visibility is easily deteriorated. SUMMARY OF THE INVENTION Accordingly, in order to eliminate the above-mentioned disadvantages, the present invention provides a condenser for an air conditioner of an air conditioner, a radiator for cooling an engine of an engine cooling device, and the engine cooling system. An engine cooling fan control device for sequentially arranging a cooling fan of the device and controlling operation of the cooling fan in accordance with a temperature state of the engine cooling water detected by the engine water temperature detecting means and an operation state of the air conditioner. , A vehicle speed detecting means for detecting a vehicle speed is provided, an evaporator temperature detecting means for detecting an evaporator temperature of the air conditioner is provided, and a vehicle speed detected by the vehicle speed detecting means in an operating state of the air conditioner is higher than a set vehicle speed. The condition and the evaporator temperature detected by the evaporator temperature detecting means are set by the evaporator. A control to stop and control the operation of the cooling fan when all of the following conditions are satisfied: a condition lower than a temperature of the cooling water and a condition that the temperature of the engine coolant detected by the engine coolant temperature detecting means is lower than a set engine coolant temperature. Means are provided. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is applicable only to a case where all the above three conditions which do not affect the power performance of the engine and the cooling performance of the air conditioner are satisfied during the operation of the air conditioner. Since the operation of the cooling fan is stopped, the power consumption required for the operation of the cooling fan can be reduced, so that the load on the engine is reduced, the fuel consumption is reduced, and the power performance of the engine is improved. Also, when the vehicle is traveling at a constant speed, the operation of the cooling fan is stopped, so that it is possible to avoid overcooling of the condenser for the air conditioner, reduce the repetition of the operation and stop of the air conditioner, and reduce the equipment of the air conditioner. To reduce the occurrence of vibrations to prevent discomfort, and if the outside air temperature is low,
The dehumidification (defrost) performance is improved by the operation of the air conditioner, whereby the fogging of the window glass can be reduced and the visibility can be improved. An embodiment of the present invention will be described below in detail with reference to the drawings. 1 to 4 show an embodiment of the present invention. 4, reference numeral 2 denotes a vehicle, 4 denotes an engine mounted on the vehicle, 6 denotes an engine room, and 8 denotes a hood. The engine 4 includes the cylinder block 1
0, a cylinder head 12 mounted on an upper portion of the cylinder block 10, and an oil pan 14 mounted on a lower portion of the cylinder block 10. The vehicle 2 includes an engine cooling device 16.
And an air conditioner (air conditioner) 18. The engine cooling device 16 includes an engine cooling radiator 20 disposed on the front side of the vehicle, an upper tank 20U of the engine cooling radiator 20 and a cylinder head 1 so as to appropriately maintain the temperature state of the engine 4.
2, a water inlet pipe 22 for communicating with a thermostat (not shown) mounted on the cylinder block 2, a lower tank 20L of the engine cooling radiator 20, and the cylinder block 1.
The radiator 20 includes a water-out pipe 24 that communicates with a water pump (not shown) attached to the radiator 20, and a cooling fan (radiator fan) 26 that is disposed on the rear side of the radiator 20. The cooling fan 26 includes a fan motor 28 and a blade 32 fixed to a motor shaft 30 of the fan motor 28, and is covered by a fan shroud 34 fixed to the back of the radiator 20. The air conditioner 18 is provided with a compressor (compressor) 36 by the driving force of the engine 4 in a cooler (cooler) as shown in FIG. To compress the gas as a medium and send it from the refrigerant passage 38 to the air conditioner condenser (condenser) 40 disposed on the front side of the vehicle. Air-cooled and liquefied in the condenser 40, this liquefied gas is sent from a receiver (liquid receiver) 42 to an evaporator (evaporator) 46 via an expansion valve (expansion valve) 44, and is vaporized. Accordingly, the heat of the air in the cabin is taken from the cabin fan 48 to cool the cabin. An air conditioner condenser 40 of the air conditioner 18 is arranged in series along the engine cooling radiator 20 on the vehicle front side of the engine cooling radiator 20. Accordingly, the vehicle 2 is provided with the air conditioner condenser 40 of the air conditioner 18, the engine cooling radiator 20 of the engine cooling device 16, and the cooling fan 26 of the engine cooling device 16 in this order from the vehicle front side. The cooling fan 26 is also used for cooling the air conditioner condenser 40 of the air conditioner 18. This cooling fan 26 is, as shown in FIG.
A control means (ECM) 50 is communicated, and the operation is controlled by the control means 50. The control means 50 includes:
Air conditioner switch 52 for turning on / off air conditioner 18
And a vehicle speed sensor 54 serving as a vehicle speed detecting means for detecting the vehicle speed.
An evaporator temperature sensor 56 as evaporator temperature detecting means for detecting gas temperature in the evaporator 46 as an evaporator temperature; and an engine water temperature sensor 58 as engine water temperature detecting means for detecting engine coolant temperature.
Has contacted. The control means 50 inputs these various sensor signals and controls the operation of the cooling fan 26 according to the temperature state of the engine cooling water detected by the engine water temperature sensor 58 and the operating state of the air conditioner 18. Things. The control means 50 controls the air conditioner 18
When the vehicle speed detected by the vehicle speed sensor 54 is higher than a preset vehicle speed (a value at which the cooling fan can be stopped at the time of operating the air conditioner) and the evaporator temperature detected by the evaporator temperature sensor 56 is A condition that is lower than the set evaporator temperature (a value at which the cooling fan can be stopped when the air conditioner is operating) and that the engine coolant temperature detected by the engine coolant temperature sensor 58 is equal to the preset engine water temperature (cooling fan drive determination value) If all the conditions below are satisfied, the operation of stopping the cooling fan 26 is stopped, that is, the air conditioner 18 is controlled under certain conditions depending on the vehicle speed state and the operation state of the air conditioner 18. During the operation, the operation of the cooling fan 26 is stopped and controlled. Next, the operation of this embodiment will be described with reference to the flowchart of FIG. When the air conditioner switch 52 is turned on (step 102), the air conditioner 18 is activated, and according to the program of the control means 50, the vehicle speed detected by the vehicle speed sensor 54 is lower than the preset vehicle speed. Whether the condition has become high, whether the evaporator temperature detected by the evaporator temperature sensor 56 has become lower than a preset evaporator temperature, and whether the engine cooling has been detected by the engine water temperature sensor 58 It is determined whether or not the condition of the water temperature is lower than a preset engine water temperature (step 104). If this step 104 is YES, the above 3
If all of the above conditions are satisfied, the operation of the cooling fan 26 is stopped and controlled while the air conditioner 18 is operating (step 106). On the other hand, if step 104 is NO,
If one of the conditions is not satisfied, the control for stopping the operation of the cooling fan 26 is prohibited, and the cooling fan 26 is stopped.
Is activated (step 108). As a result, when the air conditioner 18 is in operation, the cooling fan 26 is activated only when all the above three conditions which do not affect the power performance of the engine 4 or the cooling performance of the air conditioner 18 are satisfied. Since the operation is stopped, the power consumption required for operating the cooling fan 26 can be reduced, so that the load on the engine 4 is reduced,
The fuel consumption can be reduced, and the power performance of the engine 4 can be improved. When the vehicle 2 is traveling at a constant speed,
Since the operation of the cooling fan 26 is stopped, the air conditioner condenser 40 is cooled only by the traveling wind, thereby avoiding overcooling of the air conditioner condenser 40 and reducing the repetition of the operation and stop of the air conditioner 18. Air conditioner 1
The generation of vibrations by the device 8 can be reduced to prevent discomfort. Further, when the outside air temperature is low, the dehumidification (defrost) performance is improved by operating the air conditioner 18,
This makes it possible to improve the visibility of the window glass by removing the fogging. As a special configuration of the present invention, it is also possible to reduce the power consumption and the like by lengthening the operation stop of the cooling fan in consideration of the outside air temperature and humidity in addition to the above three conditions. Further, even if the vehicle speed is lower than the set vehicle speed, if the traveling airflow is larger than the airflow according to the actual vehicle speed due to strong wind from the front of the vehicle or the like, the operation of the cooling fan is stopped to reduce power consumption and the like. Is also possible. Furthermore, even if the vehicle speed is lower than the set vehicle speed, if the cruise traveling (constant traveling) continues for a certain period of time, there is a constant amount of wind, so that the operation of the cooling fan can be stopped to reduce power consumption and the like. It is. Furthermore, the operation of the cooling fan is stopped in accordance with the amount of change in the throttle opening, for example, in the case of sudden acceleration, the operation of the cooling fan is stopped for a predetermined time to reduce the engine load, or in the case of sudden deceleration. It is also possible to stop the operation of the cooling fan for a predetermined time to prevent waste of electric energy. Even when the above three conditions are not satisfied, if it is determined that a certain amount of cooling is required for the radiator or the like in consideration of the state of each of these conditions, the cooling fan is rotated at a rotation speed necessary for the cooling. , For example, by setting the number of revolutions of the cooling fan to a certain set value such as 50% or 80%, the cooling fan can be efficiently variably operated, and the radiator or the like can be optimally cooled. As is apparent from the above detailed description, according to the present invention, the condition that the vehicle speed detected by the vehicle speed detecting means is higher than the set vehicle speed in the operating state of the air conditioner and the condition of the evaporator temperature detecting means. When all of the conditions that the detected evaporator temperature is lower than the set evaporator temperature and the condition that the temperature of the engine cooling water detected by the engine water temperature detecting means is lower than the set engine water temperature are satisfied, the operation of the cooling fan Control means for controlling the stop of the air conditioner, only when all of the above three conditions that do not affect the power performance of the engine and the cooling performance of the air conditioner are satisfied during the operation of the air conditioner, Since the operation of the fan is stopped, the power consumption required for operating the cooling fan can be reduced.
This reduces the load on the engine, reduces fuel consumption, improves the power performance of the engine, and stops the operation of the cooling fan when the vehicle is running at a constant speed. To reduce the repetition of the operation and stop of the air conditioner, reduce the occurrence of vibrations caused by the equipment of the air conditioner to prevent discomfort, and furthermore, when the outside air temperature is low, The dehumidification (defrosting) performance is improved by the operation of the device, whereby the fogging of the window glass can be improved and the visibility can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a flowchart of operation control of a cooling fan. FIG. 2 is a block diagram of a cooling fan control device. FIG. 3 is a system configuration diagram of an air conditioner. FIG. 4 is a schematic configuration diagram of a front portion of the vehicle. [Description of Signs] 2 vehicle 4 engine 16 engine cooling device 18 air conditioner 20 engine cooling radiator 26 cooling fan 40 air conditioner condenser 50 control means 52 air conditioner switch 54 vehicle speed sensor 56 evaporator temperature sensor 58 engine water temperature sensor

Claims (1)

Claims 1. An engine water temperature detecting means, comprising: an air conditioner condenser of an air conditioner, an engine cooling radiator of an engine cooling device, and a cooling fan of the engine cooling device arranged in this order from the front side of the vehicle. In an engine cooling fan control device that controls the operation of the cooling fan according to the temperature state of the engine cooling water detected by the control unit and the operating state of the air conditioner, a vehicle speed detecting unit that detects a vehicle speed is provided.
An evaporator temperature detecting means for detecting an evaporator temperature of the air conditioner; a condition that a vehicle speed detected by the vehicle speed detecting means is higher than a set vehicle speed in an operating state of the air conditioner; and an evaporator detected by the evaporator temperature detecting means. The operation of the cooling fan is stopped when all of the conditions that the temperature is lower than the set evaporator temperature and the condition that the temperature of the engine coolant detected by the engine coolant temperature detector is lower than the set engine coolant temperature are satisfied. An engine cooling fan control device provided with control means for controlling.