Sensor cleaning system with Anti-freezing function

Abstract

The present invention relates to a sensor cleaning system for a vehicle, and more specifically, to a sensor cleaning system having an anti-freezing and thawing function in an air injection type sensor cleaning system. According to an embodiment of the present invention, the sensor cleaning system for a vehicle comprises: a distributor having a channel into which compressed air is introduced and a plurality of outlets, for distributing compressed air from the channel to each outlet; a valve formed integrally with the distributor and capable of opening and closing to allow or block the supply of compressed air through each outlet; a heating element configured to apply heat to the distributor; and a controller configured to operate the heating element when a preset condition is achieved.

Description

Technology Field

[0001] The present invention relates to a sensor cleaning system for a vehicle, and more specifically, to a sensor cleaning system having an anti-freezing and thawing function in an air injection type sensor cleaning system. Background Technology

[0002] Recently, vehicles are being equipped with driver assistance systems to support drivers in various driving situations, ensuring safe operation. Furthermore, going beyond these systems, active research and development is underway regarding autonomous vehicles capable of driving themselves without driver intervention.

[0003] In such driver assistance systems or autonomous vehicles, various types of environmental sensors capable of detecting the surrounding environment in diverse ways are installed. Examples of environmental sensors mounted on vehicles include radar, LiDAR, and cameras.

[0004] Since these sensors are mounted on the exterior of the vehicle, the sensing area can easily become dirty due to foreign substances such as dust, rain, or snow. To maintain sensor performance, these sensors must be kept clean above a certain level, so vehicles are equipped with a sensor cleaning system that can clean the sensors when the sensing area becomes contaminated. Prior art literature

[0005] Published Patent Application No. 10-2018-0136981 (Date of publication: Dec. 26, 2018) The problem to be solved

[0006] The present invention has been devised to solve the aforementioned problems, and

[0007] We aim to provide a sensor cleaning system that can prevent failures caused by freezing.

[0008] The objectives of the present invention are not limited to those mentioned above, and other unmentioned objectives will be clearly understood by those skilled in the art to which the present invention pertains (hereinafter referred to as "person skilled in the art") from the description below. means of solving the problem

[0009] The features of the present invention for achieving the objectives of the present invention as described above and for performing the characteristic functions of the present invention described below are as follows.

[0010] According to an embodiment of the present invention, a sensor cleaning system for a vehicle comprises: a distributor having a channel into which compressed air is introduced and a plurality of outlets, for distributing compressed air from the channel to each outlet; a valve formed integrally with the distributor and capable of opening and closing to allow or block the supply of compressed air through each outlet; a heating element configured to apply heat to the distributor; and a controller configured to operate the heating element when a preset condition is achieved. Effects of the invention

[0011] According to the present invention, a sensor cleaning system capable of preventing failure caused by freezing is provided.

[0012] The effects of the present invention are not limited to those described above, and other unmentioned effects will be clearly recognized by a person skilled in the art from the description below. Brief explanation of the drawing

[0013] FIG. 1 illustrates a configuration diagram of an air cleaning system according to the present invention, and FIG. 2 illustrates a schematic layout of an air cleaning system in a vehicle, and FIG. 3 schematically illustrates a sensor cleaning system according to the present invention, and FIG. 4 illustrates a configuration diagram of a sensor cleaning system capable of preventing freezing according to the present invention, and FIG. 5 illustrates a valve and a distributor according to some embodiments of the present invention, and FIG. 6 is an exploded perspective view of FIG. 5, and FIG. 7 is a cross-sectional view of the valve portion of FIG. 5, and FIG. 8 illustrates a temperature sensor provided in the valve and distributor of the present invention, and FIG. 9 is a partial side view of FIG. 5, and FIG. 10 illustrates a valve and a distributor according to some embodiments of the present invention, and FIG. 11 is a partial enlarged view of FIG. 10, and FIG. 12 is a partial enlarged view of FIG. 10, and FIGS. 13a to 15b illustrate control flow diagrams of a sensor cleaning system according to various embodiments of the present invention. Specific details for implementing the invention

[0014] The specific structural or functional descriptions presented in the embodiments of the invention are merely illustrative for the purpose of explaining embodiments according to the concept of the invention, and embodiments according to the concept of the invention may be implemented in various forms. Furthermore, it should not be interpreted as being limited to the embodiments described herein, but should be understood to include all modifications, equivalents, and substitutions that fall within the spirit and scope of the invention.

[0015] Meanwhile, in the present invention, terms such as "first" and / or "second" may be used to describe various components, but said components are not limited to said terms. For the sole purpose of distinguishing one component from other components, for example, without departing from the scope of rights according to the concept of the present invention, the first component may be named the second component, and similarly, the second component may be named the first component.

[0016] When it is stated that one component is "connected" or "connected" to another component, it should be understood that while it may be directly connected or connected to that other component, there may also be other components in between. Conversely, when it is stated that one component is "directly connected" or "directly in contact" with another component, it should be understood that there are no other components in between. Other expressions used to describe the relationship between components, such as "between" and "exactly between," or "adjacent to" and "directly adjacent to," should be interpreted in the same way.

[0017] Throughout the specification, identical reference numbers denote identical components. Meanwhile, the terms used in this specification are for describing embodiments and are not intended to limit the invention. In this specification, the singular form includes the plural form unless specifically stated otherwise in the text. As used in this specification, "comprises" and / or "comprising" do not exclude the presence or addition of one or more other components, steps, actions, and / or elements to the mentioned components, steps, actions, and / or elements.

[0019] The present invention will be described in detail below with reference to the attached drawings.

[0020] As previously explained, periodic cleaning of the sensor surfaces is necessary to maintain the performance of environmental sensors that detect the vehicle's surrounding environment. For example, environmental sensors can be contaminated by foreign substances such as dust and sand, or by raindrops and snow during precipitation. In particular, in active autonomous vehicles, driving is performed based on surrounding environmental information, such as traffic lights, pedestrians, road types, buildings, and surrounding vehicles, which is detected by environmental sensors. If the surface of the environmental sensor is contaminated by foreign substances, it becomes impossible to perceive the surrounding environment, and active autonomous driving becomes impossible. Therefore, the sensor cleaning system performs the important function of enabling driving by facilitating the environmental sensor's clear perception of the surrounding environment without distortion and by removing contaminants from the sensor surface.

[0021] Cleaning of these environmental sensors can be performed using either washer fluid or high-pressure air. In the former, the sensor is cleaned using washer fluid, and moisture is removed from the sensor surface through air jets. In the latter, foreign matter on the sensor surface is removed by spraying only high-pressure air.

[0022] Let us examine the latter air cleaning case, in which an environmental sensor is cleaned by spraying air, with reference to FIG. 1. Among the sensor cleaning systems, the air cleaning system (1) is configured to clean the environmental sensor using compressed air. The air cleaning system (1) performs cleaning by spraying compressed air onto the surface of the environmental sensor (2). The environmental sensor (2) includes a sensing device such as a lidar, radar, or camera, and can be placed on the front, rear, side, roof, etc. of a vehicle.

[0023] Specifically, air filtered through an air filter (4) provided in the vehicle is introduced into a compressor (6). The air compressed by the compressor (6) is sprayed onto the surface of the environmental sensor (2), thereby removing foreign matter from the environmental sensor (2). The environmental sensor (2) includes a plurality of environmental sensors (2a, 2b, 2c), and although three environmental sensors are disclosed in the drawings and specifications, the number is not limited thereto and can be increased or decreased.

[0024] Additionally, the air cleaning system (1) includes an air tank (8). Air can be filled into the air tank (8) by compressed air through a compressor (6) or by an external device, and the air filled into the air tank (8) can be used to clean the environment sensor (2).

[0025] The controller (10) of the air cleaning system (1) is configured to operate the valve (12), for example, a solenoid valve, at preset intervals or in preset situations, such as when contamination is detected by the environment sensor (2). This causes compressed air to be sprayed from the compressor (6) or air tank (8) to each environment sensor (2), thereby cleaning the environment sensor (2). The valve (12) is equipped with or integrally formed with a distributor (14) so ​​that the compressed air can be distributed through nozzles (16) provided for each of the plurality of environment sensors (2).

[0026] The compressor (6) is equipped with a temperature sensing unit (18), and the temperature of the compressor (6) detected by the temperature sensing unit (18) is transmitted to the controller (10) of the air cleaning system (1). The controller (10) is configured to monitor the temperature of the compressor (130) so that the compressor (6) does not operate at an operating limit temperature. When the compressor (6) reaches the operating limit temperature, the controller (10) can control the operation of the compressor (6) to stop until the temperature of the compressor (6) drops.

[0027] Referring to FIG. 2, a compressor (6) and an air tank (8) can typically be provided in the front part of the vehicle. Air must be supplied from the compressor (6) and the air tank (8) provided in the front part of the vehicle to environmental sensors (16a, 16b, 16c) located in the front (F), side, roof (R), and rear (RR) of the vehicle. At this time, the air stored at high pressure in the air tank (8) passes through a hose with a small diameter and a very long length while undergoing a rapid pressure drop in the air tank (8) and the distributor (14). Air that undergoes a rapid pressure drop can easily reach the dew point and liquefy, or water molecules in the humid air can freeze as they are.

[0028] The hose may become clogged due to the freezing of condensation formed on the inner surface of the hose, and the nozzle (16) may become clogged due to the freezing of water droplets. Additionally, the inner surface of the pressure drop point of the air tank (8) and distributor (14) may become clogged due to the rapid sublimation of air and the freezing of moisture. In such cases, sensor cleaning becomes impossible, making autonomous driving difficult due to contamination of the environment sensor and potentially causing serious accidents.

[0029] In particular, if components such as nozzles and hoses become clogged due to freezing, self-diagnosis of faults and fail-safe operation become impossible, causing the system to shut down immediately and rendering autonomous driving impossible. Additionally, aluminum is often used for air tanks to achieve lightweight design and high-pressure resistance. In this case, the rapid pressure drop during air injection causes the temperature to fall, and as the surface temperature becomes very low, the tank tends to be more vulnerable to freezing.

[0030] Accordingly, the present invention aims to provide an air cleaning system having a freezing prevention and removal function. By solving the problem of freezing caused by a sudden drop in pressure, it prevents blockage of hoses and nozzles due to freezing, thereby preventing accidents that may occur while driving, particularly during autonomous driving.

[0031] As illustrated in FIGS. 3 and 4, the air cleaning system (1) according to the present invention includes a heating element (20). In one embodiment, the heating element (20) is placed in a distributor (14). As previously described, the distributor (14) may be formed integrally with a valve (12). The heating element (20) can generate heat by an applied voltage, thereby preventing condensation and freezing in the distributor (14).

[0032] Referring to FIGS. 5 and 6, according to some embodiments of the present invention, a heating element (20) is mounted on a distributor (14) in a manner that encloses the distributor (14). As shown in FIG. 7, in one embodiment, the heating element (20) may be positioned to enclose the outside of the channel (112) portion of the valve (12) integrated with the distributor (14). In one embodiment, the heating element (20) may be provided on a bracket (30) for mounting the distributor (14) at a mounting position. In particular, the heating element (20) may be positioned on the bracket (30) to enclose the outside of the outlet (214) or the channel (112) of the distributor (14). The heating element (20) may extend along the longitudinal direction of the bracket (30), and one or two heating elements (20) may be arranged to enclose all outlet (214) sides of the distributor (14).

[0033] A connector (40) for connecting to a power supply line, a controller (10), etc. is provided in the heating element (20). The connector (40) can be oriented to facilitate assembly and attachment / detachment. Meanwhile, the heating element (20) is configured so that its path can be changed along the surface of the bracket (30). Unexplained reference numeral 114 is the inlet of the distributor (14) into which air from the air tank (8) flows.

[0034] As illustrated in FIGS. 8 and 9, the distributor (14) includes a temperature sensor (24). The temperature sensor (24) may be provided around the connector (40) and may detect the temperature around the outlet (214) or channel (112) of the distributor (14). The measurement of the temperature sensor (24) may serve as the basis for determining the operation of the heating element (20).

[0035] As illustrated in FIGS. 10 to 12, according to some embodiments of the present invention, a heating element (20) may be configured to surround each outlet (214) of a distributor (14) or each channel (112) of a valve (12). That is, a plurality of heating elements (20) may be provided in the distributor (14). Power supply to the heating element (20) and connection to the controller (10) may be integrated by a connector (50) that controls the operation of the valve (12). Alternatively, a separate connector may be provided for the heating element (20) only. A temperature sensor (24) may be provided around the outlet (214) of the distributor (14) or around the channel (112) of the valve (12) to detect the temperature.

[0036] According to some embodiments of the present invention, a heating element (20) may be placed in an air tank (8) and may be placed around the inlet (18) and outlet (28) of the air tank (8), respectively. The heating element (20) may generate heat by an applied voltage, thereby preventing the formation of condensation and freezing in the air tank (8), particularly in the inlet (18) and outlet (28) of the air tank (8). According to some embodiments of the present invention, the air tank (8) is provided with a drain valve (24) for draining water generated within the air tank (8). In some embodiments, a water level sensor (34) may be provided for measuring the water level of water generated within the air tank (8).

[0037] As a non-limiting example, the heating element (20) may be a heat pad. The outer shell and heating wire of the heat pad may be made of non-woven fabric or nichrome wire. Furthermore, the materials are not limited to these, and other possible known materials may be used. However, a material with sufficient vibration resistance and heat resistance is selected. According to the present invention, various types of heating elements (20) may be applied. As one non-limiting example, the heating element (20) may be a linear heating element. A linear heating element is a heating element with a series structure utilizing nickel, iron-chromium wire, etc. As another non-limiting example, the heating element (20) may be a planar heating element. For example, as a planar heating element, an ITO (Indium Tin Oxide) film, a metal mesh film, a transparent planar heating element film, a PTC (Positive Temperature Coefficient) heating film, a far-infrared heating film, etc. may be applied. However, the materials are not limited thereto, and applicable known heating elements may be used.

[0038] Referring again to FIG. 3, the air cleaning system (1) may further include a heating hose (22). The air passage of the air cleaning system (1) may be formed by the heating hose (22). The heating hose (22) may also be operated by an applied voltage, similar to the heating element (20). Typically, because air hoses have a very small diameter and a long length, freezing is likely to occur on the air hose due to a sudden drop in pressure caused by the discharge of high-pressure air to atmospheric pressure and very low ambient temperatures. Accordingly, the present invention can raise the temperature of the air and prevent freezing during air flow by forming the air passage with the heating hose (22).

[0039] The controller (10) receives the temperature detected by the temperature sensor (24). The controller (10) is configured to operate the heating element (20) and the heating hose (22) based on the measured temperature. When voltage is applied to the heating element (20) and the heating hose (22) according to the controller's (10) determination of whether heating is required, heat generation occurs according to the physical properties of the heating wire.

[0040] Referring to FIGS. 13a to 15b, a control method for an air cleaning system having an anti-freezing function according to the present invention will be described.

[0041] As illustrated in FIG. 13a, the controller (10) receives the vehicle's ignition being turned on (S1). When the ignition is turned on, the temperature sensor (24) continuously detects the temperature of the distributor (14), and the controller (10) collects the temperature of the distributor (14) from the temperature sensor (24). Then, the controller (10) determines whether the collected temperature of the distributor (14) is lower than a preset value (S3). Here, the preset value may be 0 degrees Celsius, but may be changed depending on the situation. If it is determined that the temperature of the distributor (14) is lower than the preset value, the controller (10) activates the heating element (20) (S5). Here, the operation of the heating element (20) may also include the operation of the heating hose (22). The same applies below, but for simplification, it will be referred to as the heating element (20). Accordingly, the temperature of the distributor (14) can be raised by the operation of the heating element (20) and the heating hose (22) to prevent freezing or to perform thawing. While operating the heating element (20), the controller (10) continuously receives temperature information from the temperature sensor (24) to determine whether the temperature of the distributor (14) reaches a preset allowable value (S7). When the temperature of the distributor (14) exceeds the allowable value, the controller (10) stops applying voltage to the heating element (20) to stop the operation of the heating element (20) (S9). As a non-limiting example, the allowable value may be 10 degrees Celsius. However, this allowable value may be changed depending on the use.

[0042] According to the present invention, the basis for determining the operation of the heating element (20) may be modified to reduce power consumption and increase system durability. According to some embodiments, as shown in FIG. 13b, the controller (10) may also use ambient temperature information as the basis for determining the operation of the heating element (20) (S3'). When the temperature of the distributor (14) and the ambient temperature are below a set value, the controller (10) may operate the heating element (20). Additionally, as shown in FIG. 13c, according to some embodiments of the present invention, the controller (10) may use whether the autonomous driving function of the vehicle is turned on as the basis for determining the operation of the heating element (20). The controller (10) determines whether the autonomous driving mode is turned on so that the heating element (20) operates only when the autonomous driving mode requires sensor cleaning (S2). Then, the operation of the heating element (20) may be determined based on the temperature of the distributor (14). The following steps are the same as those in Fig. 13a, so redundant descriptions are omitted.

[0043] As illustrated in FIG. 14, according to some embodiments of the present invention, the controller (10) can determine whether to operate the heating element (20) based on external conditions, i.e., the operating status of other systems within the vehicle, without determining whether the temperature of the distributor (14) measured by the temperature sensor (24) is below an allowable value (S4). For example, when a specific thawing system is operated to prevent failure due to freezing in another controller within the vehicle, the controller (10) can determine the operation of the heating element (20) according to the signal. To this end, the controller (10) may be configured to communicate with the controller of another system that performs thawing within the vehicle.

[0044] According to some embodiments of the present invention, the air cleaning system (1) can determine a failure of the air cleaning system (1) caused by freezing and correct it. As illustrated in FIG. 15a, when the vehicle is started (S1), the controller (10) determines whether the autonomous driving mode is turned on (S2). When the autonomous driving mode is turned on and the controller (10) opens the valve (12) for sensor cleaning, the controller (10) observes the pressure change of the distributor (14). The controller (10) determines whether the pressure change of the distributor (14) is less than a preset minimum value (S12). Even if an opening command is issued to the valve (12), if there is no pressure change of the distributor (14), blockage due to freezing can be predicted. In this case, the controller (10) determines that blockage due to freezing has occurred and operates the heating element (20) to perform thawing.

[0045] Additionally, the controller (10) can determine the possibility of freezing based on weather conditions (S14). For example, the controller (10) can collect rainfall information and ambient temperature information and determine with a higher probability of blockage due to freezing when there is no rainfall and the ambient temperature is below zero. That is, even if an opening command is issued to the valve (12) but the pressure change of the distributor (14) is below the minimum value and there is a possibility of freezing based on weather conditions, the controller (10) can operate the heating element (20) (S16).

[0046] As illustrated in FIG. 15b, according to some embodiments of the present invention, the controller (10) may use information from another controller as a basis for determining whether freezing has occurred. When the autonomous driving mode is turned on (S2), the controller (10) receives input of a failed attempt at sensor cleaning from the autonomous driving controller of the autonomous driving system (S13). For example, there may be a case where the autonomous driving controller issues a cleaning command to the controller (10) of the sensor cleaning system, but the sensor cleaning is not performed due to blockage caused by freezing. The autonomous driving controller informs the controller (10) that cleaning was not performed despite several attempts to execute sensor cleaning, and the controller (10) can determine whether the air cleaning system (1) has frozen based on this information. Additionally, the controller (10) can operate the heating element (20) (S19) to eliminate freezing when there is a possibility of freezing due to weather conditions (such as when there is no rainfall and the outside temperature is below zero) (S15) and when the pressure change of the distributor (14) is also below the minimum value (S17).

[0047] According to the present invention, failure of the air cleaning system can be prevented in advance.

[0048] The air cleaning system according to the present invention can be implemented by utilizing the addition and modification of some components and control logic without major package changes.

[0049] The air cleaning system according to the present invention can diagnose a malfunction caused by freezing and clear the freezing.

[0050] The present invention described above is not limited by the aforementioned embodiments and attached drawings, and it will be obvious to those skilled in the art that various substitutions, modifications, and changes are possible within the scope of the technical concept of the present invention. Explanation of the symbols

[0051] 1: Air cleaning system 2: Environmental sensor 4: Air filter 6: Compressor 8: Air tank 10: Controller 12: Valve 14: Distributor 16: Nozzle 18: Temperature sensor 20: Heating element 22: Heating hose 24: Temperature sensor 30: Bracket 40, 50: Connector 112: Channel 114: Entrance 214: Exit V: Vehicle

Claims

Claim 1 A sensor cleaning system for a vehicle comprising: a distributor having a channel into which compressed air is introduced and a plurality of outlets, for distributing compressed air from the channel to each outlet; a valve formed integrally with the distributor and capable of opening and closing to allow or block the supply of compressed air through each outlet; a heating element configured to apply heat to the distributor; a controller configured to operate the heating element when a preset condition is achieved; and a temperature sensor disposed in the distributor, configured to detect the temperature of the distributor and transmit it to the controller. Claim 2 delete Claim 3 A system according to claim 1, wherein the controller is configured to operate the heating element based on the temperature of the distributor received from a temperature sensor. Claim 4 A system according to claim 1, further comprising a bracket on which the distributor is mounted, wherein the heating element is located between the distributor and the bracket. Claim 5 A system according to claim 1, wherein the heating element is arranged to surround the distributor. Claim 6 A system according to claim 5, wherein the heating element is disposed in the distributor to surround the outer side of the channel. Claim 7 A system according to claim 1, wherein the heating element is provided for each outlet. Claim 8 A control method for a system according to claim 1, wherein the controller is configured to perform the steps of: receiving the temperature of the distributor from the temperature sensor; and operating the heating element when the temperature of the distributor is less than a preset value. Claim 9 A control method according to claim 8, wherein the controller is configured to perform the steps of: continuously receiving the temperature of the distributor from the temperature sensor after the operation of the heating element; and stopping the operation of the heating element when the temperature of the distributor exceeds a preset allowable value. Claim 10 A control method according to claim 8, wherein the controller is configured to perform the step of operating the heating element when the temperature of the distributor and the ambient temperature are below a set value. Claim 11 A control method for a system according to claim 1, wherein the controller is configured to perform: a step of determining whether the autonomous driving mode of the vehicle is in an ON state; and a step of operating the heating element when the autonomous driving mode of the vehicle is in an ON state and the temperature received from the temperature sensor is less than a set value. Claim 12 A system according to claim 1, wherein the controller is configured to control the operation of the valve. Claim 13 A system according to claim 12, wherein the controller is configured to operate the heating element when the pressure change of the distributor is less than a preset minimum value when the valve is opened. Claim 14 A system according to claim 13, wherein the controller is configured to operate the heating element when the ambient temperature and rainfall amount satisfy preset conditions when the heating element is operated. Claim 15 A system according to claim 12, further comprising a heating hose configured to allow compressed air discharged from the outlet to flow to a target nozzle and to generate heat. Claim 16 A system according to claim 15, wherein the controller is configured to operate the heating element when it is determined that compressed air is not injected by the target nozzle when the valve is opened.

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