AUTOMATIC DEFOG SENSOR

Abstract

There is provided herein an automatic defog sensor comprising: a flexible printed circuit board having mounted thereon a first sensor portion configured to measure a surface temperature of a windshield of a vehicle, and a second sensor portion configured to measure an interior temperature and humidity of the vehicle; a first housing configured to receive the flexible printed circuit therein and to be adhered to the surface of the windshield; and a second housing coupled to the first housing to shield the flexible printed circuit board and having a passage through which air flows.

Description

TECHNICAL FIELDThe present disclosure relates to an automatic defog sensor. More particularly, the present disclosure relates to an automatic defog sensor having a function of preventing malfunctions.BACKGROUNDGenerally, the interior and exterior of a vehicle differ by a temperature difference, so that in high humidity environments, water vapor may condense on the windows of the vehicle, resulting in fogging that obstructs vision.Fogging increases the risk of an accident, in particular fogging of the windshield can obstruct the view of the driver to the front and lead to a severe accident.For this reason, it is necessary to remove moisture from the window and prevent moisture from being generated by an air conditioner, and for this purpose, automatic defog sensors are provided which predict and / or detect fogging of the window surface.A general automatic defog sensor predicts and / or detects fogging that starts to form on the window surface, and is connected to an air conditioner to automatically prevent or remove fogging of the window. Such an automatic defog sensor is installed in the windows of the vehicle and allows the driver to travel safely.However, since the automatic defog sensor generally measures the surface temperature of the window by a temperature sensor adhered to the window surface with an adhesive member, there is a risk that a gap may be generated between a temperature measurement portion and the adhesive member for various reasons, such as a curved window surface or foreign matter that may enter between the temperature measurement portion and the adhesive member.In addition, the temperature of the window surface may be measured incorrectly, as a result of which fogging cannot be predicted and / or detected effectively.The above information disclosed in this background section is intended merely to aid in enhancing the understanding of the background of the invention and therefore may contain information that does not form the prior art already known to those skilled in the art.SUMMARY OF THE INVENTIONThe present disclosure is directed to solve the above-described problems related to the related art, and an object of the present disclosure is to provide an automatic defog sensor provided with a first air inlet hole and a second air inlet hole that form a passage through which the air flows, the first and second air inlet holes each having an inclined surface extending therefrom, exposure of the sensors being blocked by the inclined surfaces and liquid and the like being prevented from being introduced into a vehicle, thereby preventing measurement errors of the sensors.In one aspect, the present disclosure provides an automatic defog sensor, comprising: a flexible printed circuit board on which a first sensor portion configured to measure a surface temperature of a windshield of a vehicle and a second sensor portion configured to measure an internal temperature and humidity of the vehicle are mounted; a first housing configured to house the flexible printed circuit therein and to be bonded to the surface of the windshield; and a second housing coupled to the first housing to shield the flexible printed circuit board and having a passage through which air flows.In an embodiment, the flexible circuit board may include: a base substrate portion having the second sensor portion mounted thereon; and a curved substrate portion extending in a curved shape from the base substrate portion to apply pressure to the surface of the windshield.In another embodiment, the first housing may include an opening to expose the curved substrate portion.In another embodiment, the first sensor portion may be mounted on the curved substrate portion.In another embodiment, the second sensor portion may be attached to the base substrate portion and shielded by the passage.In another embodiment, the second housing may include: a first passage having a first air inlet hole formed in a direction to be coupled to the first housing; and a second passage configured to communicate with the first passage and having a second air inlet hole formed in a direction to be coupled to the first housing by being separated from the first air inlet hole.In another embodiment, the first passage may include a first inclined surface configured to guide air to flow toward the first air inlet hole, and the second passage may include a second inclined surface configured to guide air to flow toward the second air inlet hole.In another embodiment, the first inclined surface may be formed in a direction corresponding to the second inclined surface.In another embodiment, the second inclined surface may have a greater inclination angle than that of the first inclined surface.Other aspects and preferred embodiments of the present disclosure are discussed below.It is understood that the term "vehicle" or "vehicle... " or other similar term as used herein refers to motor-driven vehicles in general, such as passenger cars including sport utility vehicles (SUVs) including sport utility vehicles (German utility vehicles), buses, trucks, various commercial vehicles, watercraft including a variety of boats and ships, aircraft, and the like, and includes hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles and vehicles having other alternative fuels (e.g., fuels derived from resources other than petroleum). As a hybrid vehicle, a vehicle having two or more sources of power, for example, vehicles that are both gasoline-powered and electric-powered, is referred to herein.The above and other features of the present disclosure will be explained below.BRIEF DESCRIPTION OF THE FIGURESThe above and other features of the present disclosure will be described in detail with reference to specific embodiments illustrated in the accompanying drawings by way of example only, and thus do not limit the present disclosure, and wherein: FIG. 1 is an exploded view illustrating the state of an automatic defog sensor according to an embodiment of the present disclosure; FIG. 2 is a bottom exploded view illustrating the state of the automatic defog sensor of FIG. 1 according to an embodiment of the present disclosure; FIG. 3 is a view illustrating the assembled state of the automatic defog sensor of FIG. 1 according to an embodiment of the present disclosure; and FIG. 4 is a view illustrating airflow through the automatic defog sensor of FIG. 1 according to an embodiment of the present disclosure.It should be understood that the appended figures are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of basic principles of the invention. The specific design features of the present disclosure, including, but not limited to, specific dimensions, directions, positions, and shapes disclosed herein, will be determined in part by the particular intended application and use environment.In the figures, reference numerals refer to the same or equivalent parts of the present disclosure throughout the individual figures of the drawings.DETAILED DESCRIPTIONHereinafter, preferred embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings.Advantages and features of the present disclosure and measures for achieving the advantages and features will become more apparent from the embodiments described in detail in conjunction with the accompanying drawings.However, the present disclosure may be embodied in many different forms and is not to be construed as limited to the embodiments described herein. Rather, the embodiments are provided so that the present disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art. The present disclosure is defined only by the categories of claims.In describing the present disclosure, if a detailed explanation of a related known function or construction would unnecessarily obscure the gist of the present disclosure, such explanation would be omitted, but would be understood by those skilled in the art.FIGS. 1 and 2 are exploded views illustrating the state of an automatic defog sensor according to an embodiment of the present disclosure, FIG. 3 is a view illustrating the assembled state of the automatic defog sensor according to an embodiment of the present disclosure, and FIG. 4 is a view illustrating the flow of air through the automatic defog sensor of FIG. 1 according to an embodiment of the present disclosure.As illustrated in FIGS. 1 and 2, the automatic defog sensor according to this embodiment includes a flexible circuit board 100, a first housing 200, and a second housing 300.On the flexible circuit board 100, a first sensor portion 102 configured to measure the surface temperature of a windshield of a vehicle and a second sensor portion 104 configured to measure the interior temperature and humidity of the vehicle are mounted.Specifically, on the flexible circuit board 100, a first sensor portion 102 aincluding a temperature sensor configured to measure the surface temperature of a windshield and a second sensor portion 104 including a temperature sensor configured to measure the interior temperature of the vehicle and a humidity sensor configured to measure the interior humidity of the vehicle are mounted.Since the second sensor portion 104 includes the temperature sensor and the humidity sensor that are separately attached to the flexible circuit board 100, the second sensor portion 104 may preferably measure the internal temperature and the internal humidity of the vehicle, and the temperature sensor and the humidity sensor may be used together with the first sensor portion 102 to accurately calculate the dew point temperature.The flexible circuit board 100 includes a base substrate portion 110 and a curved substrate portion 120.The base substrate portion 110 is disposed inside the first housing 200 and shielded from the outside together with the second sensor portion 104 when the second housing 300 is coupled to the first housing 200.The base substrate portion 110 may be supported by a hollow support portion 210 of the first housing 200. The hollow support portion 210 has a hollow shape and protrudes toward the second housing 300 and supports the central portion of the base substrate portion 110.Here, the hollow support portion 210 may have a rectangular shape with a hollow portion, and as such, the base substrate portion 110 is supported by the edge of the first housing 200 and the hollow support portion 210. Therefore, the base substrate portion 110 and the curved substrate portion 120 can be insulated by the edge of the first housing 200 and the cavity in the hollow support portion 210, and accordingly, the base substrate portion 110 and the curved substrate portion 120 can be insulated from the ambient heat, whereby the first sensor portion 102 can more accurately measure the temperature of the surface of a windshield 10.Moreover, the base substrate portion 110 may have a structure in which a circuit is formed on a substrate made of a material having bendable properties.In this structure, the curved substrate portion 120 extends in a curved shape from the base substrate portion 110 to apply pressure to the surface of the windshield.The curved substrate portion 120 includes a contact portion 120 a, and the curved substrate portion 120 extends from the base substrate portion 110 in a curved shape having a predetermined length so that the contrast portion 120 acan be pulled out through an opening 200 ain the first case 200 to press against the surface of the windshield.To this end, the curved substrate portion 120 is configured to form or press not only the surface of the windshield but also the surface of the window, the mirror, etc., and has its own stress.In other words, the curved substrate portion 120 having characteristics such as natural flexibility is integrated with the base substrate portion 110 and connected to the base substrate portion 110 by circuits.Since the substrate curved portion 120 is bent and deformed when contacting the surface of the windshield in a state where the contact portion 120 ais pulled out through the opening 200 ain the first case 200, the substrate curved portion 120 can be held in close contact with the surface of the windshield by the stress. For this reason, although the surface of the windshield is curved, the contact portion 120 amay deform to conform to the curved shape of the surface of the windshield, thereby effectively bringing the curved substrate portion 120 into close contact with the surface of the windshield by the stress.In other words, when the contact portion 120 ais brought into contact with the surface of the windshield, the substrate curved portion 120 may act as a spring via the tension, and moreover, without a pressing agent such as an additional spring or a push rod, the substrate curved portion 120 may not only improve the thermal contact with the surface of the windshield but also minimize the thermal mass due to the omission of an additional pressing agent.The contact portion 120 ahas an inner side to which the first sensor portion 102 is attached. The first sensor portion 102 is a temperature sensor, and is configured to measure the surface temperature of the windshield via the curved substrate portion 120 in a state where the contact portion 120 ais brought into contact with the surface of the windshield.Since the curved substrate portion 120 can be held in close contact with the surface of the windshield by its own stress even though the surface of the windshield is curved, the first sensor portion 102 can quickly and accurately measure the temperature of the surface of the windshield through the curved substrate portion 120 in a state where the sensor portion 120 ais pulled out through the opening 200 ain the first case 200 to contact the surface of the windshield, thereby enabling a quick and accurate response to changes in the fogging conditions to thereby effectively remove the fog on the surface of the windshield.Meanwhile, the first housing 200 accommodates the flexible circuit board 100 therein and adheres to the surface of the windshield.In other words, the first housing 200 may be bonded to the surface of the windshield with a separate adhesive member (not illustrated). Here, the adhesive member (not illustrated) may have a shape corresponding to that of the first housing 200, for example, without excluding the opening 200 a.The adhesive member (not shown) may be double-sidedly adhesive so that one adhesive side may be adhered to the first case 200 excluding the opening 200 aand the other adhesive side may be adhered to the surface of the windshield so that the first case 200 including the flexible circuit board 100 and the second case 300 may be stably adhered to the surface of the windshield.Preferably, the adhesive member (not shown) may be made of a soft material, for example, a double-sided adhesive tape, so that the adhesive member has sufficient adhesive force even when the first case 200 is adhered to a curved surface of the windshield.Meanwhile, the second housing 300 is coupled to the first housing 200 to shield the flexible circuit board 100 located inside from the outside and have a passage through which the air flows.Specifically, as illustrated in FIG. 3, the second housing 300 includes a first passage 310 and a second passage 320.The first passage 310 includes a first air inlet hole H 1 formed in a direction to be coupled to the first housing 200 (see FIG. 1 ).Moreover, the second passage 320 communicates with the first passage 310, and includes a second air inlet hole H 2 formed in a direction to be coupled to the first housing 200 by being separated from the first air inlet hole H 1 (see FIG. 2 ).Here, the first passage 310 includes a first inclined surface 310 aconfigured to guide air to flow toward the first air inlet hole H 1, and the second passage 320 includes a second inclined surface 320 aconfigured to guide air to flow toward the second air inlet hole H 2.Preferably, the first inclined surface 310 aof the first passage 310 has an inclination in a direction corresponding to the second inclined surface 320 aof the second passage 320, and more preferably, the first inclined surface 310 aof the first passage 310 extends with a greater length (range) and a smaller inclination angle than the second inclined surface 320 aof the second passage 320.The above structure is intended to provide an efficient air flow. When air flows into the first air inlet hole H 1 in the first passage 310 along the first inclined surface 310 aand is introduced into the first housing 200 and the second housing 300 in the arrow direction illustrated in FIG. 4, the air flows through the second air inlet hole H 2 facing the first air inlet hole H 1 to be discharged through the second passage 320 along the second inclined surface 320 a. Here, as described above, the first inclined surface 310 aand the second inclined surface 320 adiffer in the direction of inclination, length (range), and inclination angle, which facilitates the flow of the introduced and discharged air.Conventionally, a separate filter has been installed to prevent foreign matter from flowing into the flexible circuit board 100, which inevitably involved the problem that a structure for mounting the filter has to be provided.In this sense, the filter may be removed from the second housing 300 to solve the problem. Without the filter, however, the second sensor portion 104 is directly exposed to the outside world. Thus, when liquid sprayed from the vehicle interior onto the windshield enters the second sensor portion 104, this may cause malfunction of the sensor.For this reason, in the present embodiment, a structure such as the first passage 310 having the first inclined surface 310 aand the second passage 320 having the second inclined surface 320 a, each configured to block the exposure of the first housing 200 and the second housing 300 having the second sensor portion 104, is adopted that allows inflow and outflow of air flowing along the first inclined surface 310 aand the second inclined surface 320 athrough the first air inlet hole H 1 and the second air inlet hole H 2, respectively. Therefore, when liquid or the like enters the first housing 200 and the second housing 300 by removing the filter, the moisture can be easily evaporated by the air flow, thereby avoiding measurement errors of the second sensor portion 104, and finally improving the measurement accuracy of the second sensor portion 104 that measures the internal temperature and humidity.Thus, according to the present disclosure, an automatic defog sensor is provided with a first air inlet hole and a second air inlet hole that form a passage through which the air flows, the first and second air inlet holes each having an inclined surface extending therefrom, exposure of the sensors being blocked by the inclined surfaces and liquid and the like being prevented from being introduced into a vehicle, thereby preventing measurement errors of the sensors.Furthermore, according to the present disclosure, the air flow through the first and second air inlet holes can be facilitated, whereby the flowing air can directly reach the sensor, so as to improve the sensing speed and measurement accuracy of the sensor.In the foregoing, embodiments of the present invention have been described with reference to the accompanying drawings. However, those skilled in the art to which the present disclosure pertains will understand that various modifications thereof can be made and that all or a part of the above-described embodiment(s) can be selectively combined. Therefore, the true technical scope of the present disclosure should be determined by the technical ideas of the appended claims.

Claims

An automatic defog sensor comprising: a flexible printed circuit board on which a first sensor portion configured to measure a surface temperature of a windshield of a vehicle and a second sensor portion configured to measure an internal temperature and humidity of the vehicle are mounted; a first housing configured to receive the flexible printed circuit therein and to be adhered to the surface of the windshield; and a second housing coupled to the first housing to shield the flexible printed circuit board and having a passage through which air flows.The automatic defog sensor of claim 1, wherein the flexible circuit board comprises: a base substrate portion having the second sensor portion mounted thereon; and a curved substrate portion extending in a curved shape from the base substrate portion to apply pressure to the surface of the windshield.The automatic defog sensor of claim 2, wherein the first housing comprises an opening to expose the curved substrate portion.The automatic defog sensor of claim 2, wherein the first sensor portion is mounted on the curved substrate portion.The automatic defog sensor of claim 2, wherein the second sensor portion is attached to the base substrate portion and shielded by the passage.The automatic defog sensor according to claim 1, wherein the second housing comprises: a first passage having a first air inlet hole formed in a direction to be coupled to the first housing; and a second passage configured to communicate with the first passage and having a second air inlet hole formed in a direction to be coupled to the first housing by being separated from the first air inlet hole.The automatic defog sensor of claim 6, wherein: the first passage comprises a first inclined surface configured to guide air to flow toward the first air inlet hole, and the second passage comprises a second inclined surface configured to guide air to flow toward the second air inlet hole.The automatic defog sensor according to claim 7, wherein the first inclined surface is formed in a direction corresponding to the second inclined surface.The automatic defog sensor of claim 7, wherein the second inclined surface has an inclination angle greater than that of the first inclined surface.

Images