Method for controlling a closing device of an inlet opening for a cooling medium of a motor vehicle

Abstract

Method for controlling a closing device of an inlet opening for a cooling medium upstream of an intake air duct of an internal combustion engine of a motor vehicle, wherein the inlet opening can be opened or closed in a watertight manner via the closing device, wherein the closing device can be actuated by means of an actuator controlled by an electronic control unit, wherein the electronic control unit receives signals from a sensor installed on the motor vehicle which detects whether a certain height of water is on the roadway below the motor vehicle and, from a defined minimum height of water detected by the sensor, controls the actuator so that the inlet opening is closed, wherein the sensor measures the distance between the underside of the vehicle and the water on the roadway to detect the water height.

Description

[0001] The invention relates to a method for controlling a closing device of an inlet opening for a cooling medium of a motor vehicle according to the preamble of patent claim 1.

[0002] From DE 100 53 146 A1 a method for controlling a closing device of an inlet opening for a cooling medium in front of an exhaust air duct of an internal combustion engine of a motor vehicle is already known, wherein the inlet opening can be opened or closed in a watertight manner via a closing device.

[0003] Furthermore, DE 10 2008 023 560 A1 already discloses a system for regulating the volume flow of a gaseous cooling medium in vehicles. The system comprises a plurality of rotatably mounted fins. The rotational movement of the fins is initiated by a gear mechanism, and the fins are designed such that, when closed, they essentially prevent the inflow of the gaseous cooling medium and, when open, they essentially do not impede the inflow of the gaseous cooling medium. The fins can be designed such that, when closed, they are essentially watertight.

[0004] Further prior art documents include DE 10 2006 016 433 B4, DE 10 2008 046 313 A1 and GB 113 433 A.

[0005] The object of the invention is to provide a method for controlling a closing device of an inlet opening for a cooling medium of a motor vehicle, which is known from the prior art.

[0006] This object is achieved by a method for controlling a closing device of an inlet opening for a cooling medium of a motor vehicle having the features of patent claim 1.

[0007] According to the invention, the inlet opening for a cooling medium of a motor vehicle is sealed watertight with a closing device when a sensor installed on the motor vehicle detects that a certain water level has been reached on the roadway below the vehicle. For this purpose, the closing device can be actuated by an actuator controlled by an electronic control unit. The electronic control unit receives the signals from the sensor and thus detects when the actuator needs to be activated to close the inlet opening.

[0008] When a motor vehicle drives through a significant amount of water on the road, there is always a risk of damage to components of the vehicle. Particularly in classic passenger vehicles with a relatively low-slung body, there is a risk that water may penetrate through a cooling air opening at the front of the vehicle while driving through the water accumulation and, in the worst case, be sucked into an intake air duct of an internal combustion engine. This can lead to serious damage to the internal combustion engine. Such damage can now be avoided by the method according to the invention, since the inlet opening is sealed watertight before water standing on the road can penetrate through the inlet opening.

[0009] Various closing devices for cooling air intakes are already known from the prior art. However, these known closing devices serve solely to save energy. Immediately after starting an internal combustion engine, it is still cold and therefore not yet at its optimal efficiency. Due to the known closing devices for cooling air intakes, it is possible that the engine has not reached its operating temperature or has only partially reached it. This allows the internal combustion engine to reach its optimal operating temperature more quickly, which leads to fuel savings. Every intake opening on the exterior of a vehicle also impairs aerodynamics. As long as the intake opening is closed, the negative aerodynamic effects are smaller than when the intake opening is open.

[0010] The present invention adds to the known prior art the prevention of water ingress through the inlet opening during water crossings. If it is detected that water is being passed, i.e., that the motor vehicle is passing through a correspondingly high accumulation of water, then, according to the invention, the inlet opening for the cooling medium is closed, so that no water from the accumulation of water can undesirably penetrate through the inlet opening.

[0011] To do this, the water level sensor measures the distance between the underside of the vehicle and the water on the road. The sensor can be a camera, a light barrier, or a distance sensor of a vehicle's parking aid, for example. The sensor can be installed, for example, near the front bumper of the vehicle. Alternatively, such a sensor can also be an ultrasonic sensor, which uses ultrasound to measure the distance between the underside of the vehicle and the water on the road, thus detecting a significant accumulation of water on the road.

[0012] In most motor vehicles, such an inlet opening for a cooling medium with a closing device is used primarily in front of the intake air duct of an internal combustion engine. The cooling medium entering through the inlet opening, which in this case consists of the air surrounding the vehicle, reaches the intake air duct behind the inlet opening directly. The method according to the invention prevents water from entering through the inlet opening and being accidentally sucked in when the vehicle passes through water, which would significantly damage the internal combustion engine. In this application, the actual achievable benefit justifies the relatively high expenditure.

Claims

[1] Method for controlling a closing device of an inlet opening for a cooling medium in front of an intake air duct of an internal combustion engine of a motor vehicle, wherein the inlet opening can be opened or closed in a watertight manner via the closing device, wherein the closing device can be actuated by means of an actuator controlled by an electronic control unit, wherein the electronic control unit receives signals from a sensor installed on the motor vehicle which detects whether a certain height of water is on the roadway below the motor vehicle and, from a defined minimum height of water detected by the sensor, controls the actuator so that the inlet opening is closed, wherein the sensor measures the distance between the underside of the vehicle and the water on the roadway to detect the water height. [2] Method according to claim 1, characterized by that the sensor is a camera, a light barrier or a distance sensor.