Cooling structure of vehicle front part

Abstract

To improve reduction and electricity cost of specific air resistance by making the opening of a grill shutter to the appropriate opening on the basis of negative pressure before a radiator.SOLUTION: A cooling structure 10 of a vehicle front part comprises a radiator 18, an electric fan 20, a grill shutter 14 which is provided on a vehicle front direction of the radiator 18 and an ECU 22 which adjusts opening of the grill shutter 14 on the basis of negative pressure before the radiator which is presumed by a negative pressure table corresponding to actual load of the electric fan 20.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] This specification discloses an improvement to a cooling structure for a front portion of a vehicle. [Background technology]

[0002] Patent Document 1 discloses a control method for a grill shutter for a vehicle, which suppresses an increase in weight, selects a mode according to the situation, and improves fuel efficiency. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-282209 A Summary of the Invention [Problem to be solved by the invention]

[0004] The cooling structure provided at the front of the vehicle has a grill shutter and an electric fan. However, conventionally, the opening degree of the grill shutter and the rotation speed of the electric fan have been controlled separately and not in conjunction with each other. Therefore, if the opening degree of the grill shutter is larger than necessary, the vehicle is subjected to extra air resistance, resulting in a deterioration in power consumption and a shortened driving range. On the other hand, if the opening degree of the grill shutter is smaller than necessary, an extra load is placed on the electric fan, resulting in a deterioration in power consumption and a shortened driving range due to the power consumption of the auxiliary equipment. It is possible to control the opening degree of the grill shutter according to the vehicle speed, but the pressure state in the space in front of the radiator (referred to as "radiator front load" in this specification) changes depending on the wind force and wind direction in the driving environment (around the vehicle), so the opening degree of the grill shutter is not appropriate.

[0005] The objective of the cooling structure for the front part of a vehicle disclosed in this specification is to reduce air resistance and improve power consumption by setting the opening degree of the grill shutter to an appropriate opening degree based on the negative pressure in front of the radiator. [Means for solving the problem]

[0006] The cooling structure for the front of a vehicle disclosed in this specification is characterized by comprising a radiator, an electric fan, a grill shutter provided forward of the radiator on the vehicle, and a processor that adjusts the opening degree of the grill shutter based on a negative pressure in front of the radiator estimated using a negative pressure table corresponding to the actual load of the electric fan. Effect of the Invention

[0007] According to the cooling structure for the front part of the vehicle disclosed in this specification, the opening degree of the grill shutter can be appropriately set based on the negative pressure in front of the radiator, thereby reducing air resistance and improving power consumption. [Brief description of the drawings]

[0008] [Figure 1] 1 is a schematic diagram of a cooling structure for a front portion of a vehicle according to an embodiment of the present invention; [Diagram 2] 4 is a flowchart showing a process flow of an ECU. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] 1 is a schematic diagram of a vehicle front cooling structure 10 according to this embodiment. The vehicle front cooling structure 10 includes a grill shutter duct 12, a grill shutter 14, a radiator duct 16, a radiator 18, an electric fan 20, and an ECU 22.

[0010] The grill shutter duct 12 sends wind from the front of the vehicle to the grill shutter 14. The grill shutter 14 can be opened and closed to adjust the amount of wind sent from the grill shutter duct 12 to the radiator duct 16. The radiator duct 16 sends the wind from the grill shutter 14 to the radiator 18. The radiator 18 is a device for dissipating heat from a component to be cooled, such as an engine. The electric fan 20 is a device for sending wind to the component to be cooled. The ECU 22 is composed of a processor. The ECU 22 controls the rotation amount of the electric fan 20 (i.e., the amount of wind sent from the electric fan 20 to the component to be cooled) in response to a request from the component to be cooled. The ECU 22 also controls the opening degree of the grill shutter 14. The control of the opening degree of the grill shutter 14 will be described in detail later. A negative pressure table is stored in a memory in the ECU 22 or in a memory accessible from the ECU 22. The negative pressure table indicates the relationship between the actual load of the electric fan 20 and the negative pressure in front of the radiator.

[0011] FIG. 2 is a flowchart showing the flow of processing by the ECU 22.

[0012] In step S10, the ECU 22 obtains a required rotation speed of the electric fan 20 in response to a request from the component to be cooled.

[0013] In step S12, the ECU 22 obtains the current actual rotation speed of the electric fan 20.

[0014] In step S14, the ECU 22 determines whether the actual rotation speed of the electric fan 20 acquired in step S12 has reached the requested rotation speed acquired in step S10. If the actual rotation speed of the electric fan 20 has reached the requested rotation speed, the process proceeds to step S16.

[0015] In step S16, the ECU 22 acquires the actual load of the electric fan 20.

[0016] In step S18, the ECU 22 estimates the negative pressure in front of the radiator based on the actual load of the electric fan 20 acquired in step S16 and the negative pressure table described above.

[0017] In step S20, the ECU 22 determines the amount of adjustment of the opening degree of the grill shutter 14 according to the negative pressure in front of the radiator estimated in step S18.

[0018] In step S22, the ECU 22 outputs an opening command to the grill shutter 14 based on the current opening degree of the grill shutter 14 and the opening degree adjustment amount determined in step S20.

[0019] According to the cooling structure 10 for the front part of the vehicle in this embodiment, it is possible to reduce air resistance and improve power consumption by setting an appropriate opening degree of the grill shutter 14 based on the negative pressure in front of the radiator estimated by a negative pressure table corresponding to the actual load of the electric fan 20.

[0020] The above describes an embodiment of the cooling structure for the front part of a vehicle according to the present disclosure, but the cooling structure for the front part of a vehicle according to the present disclosure is not limited to the above embodiment, and various modifications are possible without departing from the spirit thereof.

[0021] Since the pressure in front of the radiator is more sensitive to vehicle speed (especially in the high-speed range) than to wind speed or wind direction, the target opening of the grill shutter 14 is determined by the vehicle speed, and the above control is sometimes used as a correction term. Also, by preparing data tables for the positive pressure side as well as the negative pressure side, it is possible to reduce the driving speed of the electric fan 20 and reduce power consumption when the grill shutter 14 is fully closed or slightly open. [Explanation of symbols]

[0022] 10 Cooling structure at front of vehicle, 12 Grill shutter duct, 14 Grill shutter, 16 Radiator duct, 18 Radiator, 20 Electric fan, 22 ECU.

Claims

[Claim 1] A radiator, Electric fan and a grill shutter provided forward of the radiator; a processor that adjusts an opening degree of the grill shutter based on a negative pressure in front of the radiator estimated using a negative pressure table corresponding to an actual load of the electric fan; A cooling structure for a front part of a vehicle comprising:

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