Active defogging reversible moisture absorption structure of vehicle lamp

Abstract

The utility model discloses a kind of active defogging reversible moisture-absorbing structures of car light, including T-shaped casing, PTC heater, moisture absorbent, screen, baffle, rubber valve and waterproof air-permeable membrane. Shell has main shell portion that extends into car light and end cap portion of outside, and its cavity is divided into inner cavity portion and outer cavity portion. PTC heater is sealedly installed in the installation port of main shell portion by pressing plate, and its inner and outer sides are respectively attached to positive and negative pole heat-conducting metal sheet. Moisture absorbent is contained in inner cavity portion, and two ends are fixed by screen. Baffle is arranged in outer cavity portion, and buckle hole is provided in the center, and air-permeable hole is uniformly distributed in periphery. Umbrella-shaped rubber valve is buckled in buckle hole, and can open and close air-permeable hole under the action of air pressure difference. Waterproof air-permeable membrane is welded on the outer side end of outer cavity portion. The utility model realizes the active defogging of car light efficiently and durably by the reversible regeneration of moisture absorbent realized by PTC heating, combined with the automatic pressure regulation of rubber valve and the protection of waterproof air-permeable membrane, and the structure is compact, and installation and maintenance are convenient.

Description

Technical Field

[0001] This utility model belongs to the field of vehicle headlight defogging technology, specifically, it relates to a reversible moisture absorption structure for active defogging of vehicle headlights. Background Technology

[0002] In practical applications of automotive headlights, the temperature difference between the internal light source and the external environment causes moisture in the air to condense on the inner walls of the headlight, forming fog. This severely affects the headlight's illumination and reduces nighttime driving safety. Existing defogging methods have the following shortcomings: Passive ventilation: relies solely on the tiny gaps in the headlights for natural ventilation, resulting in extremely low defogging efficiency and an inability to cope with high humidity environments; Simple heating type: The headlight glass is directly heated by heating wires. Although it can temporarily remove fog, the heat distribution is uneven and it cannot eliminate moisture at the source, so fog is easy to form repeatedly. Traditional moisture-absorbing type: It uses local moisture-absorbing materials, which have limited moisture absorption capacity and cannot remove moisture in time. The defogging effect will be greatly reduced after long-term use.

[0003] Therefore, developing a vehicle headlight defogging structure that can actively absorb moisture, conduct efficiently, and continuously evaporate is of great significance for improving headlight performance and driving safety. Utility Model Content

[0004] In view of this, the technical problem to be solved by this utility model is to provide a moisture absorption and conduction defogging structure for vehicle lights, so as to avoid the problem of poor effect of previous defogging methods inside vehicle lights.

[0005] To solve the above-mentioned technical problems, this utility model discloses a moisture-proof, breathable, and defogging structure for vehicle lights, comprising: The system comprises a housing, mounting port, PTC heater, desiccant, two screens, a partition, a rubber valve, and a waterproof and breathable membrane. The housing is T-shaped, consisting of a main housing section extending into the headlight and an end cap section located outside the headlight. The housing has a through-cavity, divided into an inner cavity corresponding to the main housing section and an outer cavity corresponding to the end cap section. The mounting port is located on the side wall of the main housing section, with a pressure plate sealing its outer side. A PTC heater is fixedly mounted on the inner side of the pressure plate. Positive and negative heat-conducting metal sheets are tightly fitted to the inner and outer sides of the PTC heater, respectively. A wire through-hole is provided on the pressure plate for the PTC heater's wires to pass through. The desiccant is contained within the inner cavity section to absorb moisture from inside the headlight. Two screens are located at both ends of the inner cavity section, near the end of the main housing section extending into the headlight and the end connecting the inner and outer cavities, respectively, to secure the desiccant and allow airflow. The partition is fixedly installed inside the outer cavity. A snap-fit ​​hole is located in the center of the partition, and multiple vent holes are evenly distributed around the outer ring of the snap-fit ​​hole. A rubber valve snaps into the snap-fit ​​hole and opens or closes the vent holes under the pressure difference between the inner and outer cavities, achieving automatic pressure regulation. A waterproof and breathable membrane is welded to the outer end of the outer cavity to prevent external moisture and dust from entering while allowing water vapor to escape.

[0006] Preferably, the cross-sectional area of ​​a single vent hole in the partition is 0.19–7.06 mm². 2 To ensure proper breathability and pressure response.

[0007] Preferably, the desiccant is a superabsorbent polymer resin with high hygroscopicity and reversible regeneration properties, which can release moisture by heating.

[0008] Preferably, there are two rubber valves, which are snapped into the snap-in holes with opposite orientations to improve the demisting efficiency.

[0009] Preferably, the rubber valve is umbrella-shaped, including a rod portion that snaps into a snap-in hole and an umbrella portion that presses against the partition from the outside; the rod portion is inverted, with its free end extending to the inside of the vent and exposed; the inner side of the umbrella portion has a concave arc facing the vent, and the umbrella portion gradually thins from the inside to the outside, with a raised edge to adapt to the opening action driven by air pressure difference, thereby improving sealing and response sensitivity.

[0010] Preferably, a sealing ring is provided at the mounting joint between the housing and the rear side of the headlight. The housing can be detachably installed on the back of the headlight by means of threaded connection or snap-fit ​​connection, which is convenient for maintenance and replacement.

[0011] Preferably, the venting opening pressure of the rubber valve is 0.5 to 5.8 kPa to ensure reliable operation under normal changes in vehicle headlight pressure.

[0012] Compared with the prior art, the present invention can achieve the following technical effects: The active heating by the PTC heater promotes the regeneration of the desiccant, achieving reversible moisture absorption and extending its service life.

[0013] The rubber valve and the waterproof and breathable membrane work together to automatically regulate the internal pressure, prevent external contaminants from entering, and improve reliability.

[0014] With its compact structure and easy installation, it is suitable for various types of vehicle lights, reducing maintenance costs.

[0015] Of course, any product implementing this utility model does not necessarily need to achieve all of the above-mentioned technical effects at the same time. Attached Figure Description

[0016] The accompanying drawings, which are included to provide a further understanding of the present invention and constitute a part of this invention, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a cross-sectional schematic diagram of the vehicle headlight moisture absorption and conduction defogging structure according to an embodiment of this utility model; Figure 2 This is a schematic diagram of the vehicle headlight moisture absorption and conduction defogging structure installed in a vehicle headlight according to an embodiment of this utility model; Figure 3 This is a schematic diagram of the air inlet and outlet of the rubber valve in an embodiment of this utility model.

[0017] Attached Figure Labels

[0018] 10 housing, 11 main housing, 12 end cap, 21 inner cavity, 22 outer cavity, 30 mounting port, 40 pressure plate, 50 PCT heater, 51 positive heat-conducting metal sheet, 52 negative heat-conducting metal sheet, 53 wire, 60 desiccant, 71 screen, 72 screen, 80 partition, 81 snap-fit ​​hole, 82 vent hole, 90 rubber valve, 91 rod, 92 umbrella, 100 waterproof and breathable membrane, 110 sealing ring. Detailed Implementation

[0019] The following will describe in detail the implementation of this utility model with reference to the accompanying drawings and embodiments, so that the implementation of this utility model can be fully understood and carried out based on how technical means are used to solve technical problems and achieve technical effects.

[0020] Please refer to Figure 1 and Figure 2 , Figure 1 This is a cross-sectional schematic diagram of the vehicle headlight moisture absorption and conduction defogging structure according to an embodiment of this utility model; Figure 2 This is a schematic diagram of the vehicle headlight moisture absorption and conduction defogging structure installed in a vehicle headlight according to an embodiment of this utility model.

[0021] As shown in the figure, a vehicle headlight moisture-absorbing and defogging structure includes a housing 10, which is T-shaped and consists of a main housing portion 11 and an end cap portion 12. The main housing portion 11 extends into the vehicle headlight, and the end cap portion 12 is located outside the vehicle headlight. The housing 10 has a through cavity, which is divided into an inner cavity portion 21 and an outer cavity portion 22. The inner cavity portion 21 contains a desiccant 60, which is preferably a superabsorbent polymer, such as sodium polyacrylate, which has a large moisture absorption capacity and can be reversibly used by desorbing moisture through heating.

[0022] The main housing 11 has a mounting opening 30 on its side wall. A pressure plate 40 is sealed to the outside of the mounting opening 30 by a snap fastener or bolt and a sealing gasket. A PTC heater 50 is fixedly mounted on the inner side of the pressure plate 40. A positive heat-conducting metal sheet 51 and a negative heat-conducting metal sheet 52 are tightly fitted to the inner and outer sides of the PTC heater 50, respectively, for efficient heat conduction. A wire hole is provided on the pressure plate 40, through which the wire 53 of the PTC heater 50 is led out and connected to the vehicle lighting power system. When the PTC heater 50 is powered on, it generates heat, heating the desiccant 60, causing it to release the absorbed moisture and achieve regeneration. The PTC heater has a power of 5-10W and an operating temperature range of 80-120℃.

[0023] Screens 71 and 72 are respectively provided at both ends of the inner cavity 21. Screen 71 is located near the end of the main housing 11 that extends into the headlight, and screen 72 is located near the end of the inner cavity 21 that connects to the outer cavity 22. Screens 71 and 72 are made of metal or plastic and have small mesh sizes. They are used to fix the desiccant 60 while allowing moisture to enter the headlight and dry air to exit.

[0024] A partition 80 is fixedly installed inside the outer cavity 22. A snap-fit ​​hole 81 is formed in the center of the partition 80, and multiple vent holes 82 are evenly distributed around the outer ring of the snap-fit ​​hole 81. The cross-sectional area of ​​each vent hole 82 is 0.19–7.06 mm². 2 For example, the diameter of the circular orifice is 0.5–3 mm to ensure smooth airflow under normal pressure. The rubber valve 90 snaps into the snap-fit ​​hole 81. The rubber valve 90 is umbrella-shaped, including a stem 91 and an umbrella portion 92. The stem 91 is inverted, with its free end extending to the inside of the vent hole 82 and exposed for easy installation and fixation. The inner side of the umbrella portion 92 has a concave arc, facing the vent hole 82, and gradually thins from the inside to the outside, with a raised edge. When a pressure difference occurs between the inner cavity 21 and the outer cavity 22 (such as when the internal temperature of the headlight increases the pressure), the umbrella portion 92 is pushed open, opening the vent hole 82 to achieve pressure balance; when the pressure is balanced, the umbrella portion 92 closes the vent hole 82 under elastic action to prevent backflow of external air. The vent opening pressure of the rubber valve 90 is set to 0.5–5.8 kPa to accommodate typical pressure changes during headlight operation.

[0025] A waterproof and breathable membrane 100 is welded to the outer end of the outer cavity 22. The waterproof and breathable membrane 100 is made of materials such as polytetrafluoroethylene (ePTFE) and has a microporous structure, allowing water vapor to pass through but blocking liquid water and dust. A sealing ring 110 is fitted at the mounting joint between the housing 10 and the rear side of the headlight. The housing 10 can be detachably installed on the back of the headlight by means of threaded connection or snap-fit ​​connection, which is convenient for daily maintenance and replacement of desiccant.

[0026] During operation, moisture inside the headlight enters the inner cavity 21 through the screen 71 and is absorbed by the desiccant 60. When the headlight is turned on or the ambient temperature changes, the operator activates the PTC heater 50 on the vehicle's main control panel, heating the desiccant 60 to desorb moisture. The moisture then passes through the screen 72 into the outer cavity 22. Simultaneously, the internal pressure of the headlight increases, pushing the rubber valve 90 to open, allowing moisture to escape to the outside through the vent 82 and the waterproof and breathable membrane 100. When the pressure decreases, the rubber valve 90 closes to prevent external humid air from entering. This cycle repeats, achieving active defogging and reversible moisture absorption.

[0027] In a preferred embodiment, please refer to Figure 3 , Figure 3 This is a schematic diagram of the air inlet and outlet of the rubber valve according to an embodiment of this utility model. Two rubber valves 90 are provided, facing opposite directions and snapped into the snap-in holes 81, improving demisting efficiency. Figure 3 In the diagram, 'a' represents the intake schematic. Figure 3 In the diagram, b represents the air outlet.

[0028] This invention has a simple structure and low cost, and is applicable to various types of vehicle lights such as headlights and taillights, effectively improving the performance and safety of vehicle lights.

[0029] The foregoing description illustrates and describes several preferred embodiments of the present invention. However, as previously stated, it should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the inventive concept described herein through the foregoing teachings or techniques or knowledge in related fields. Any modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

Claims

1. A reversible moisture-absorbing structure for active defogging of vehicle lights, characterized in that, include: The housing is T-shaped and has a main housing portion extending into the headlight and an end cap portion located outside the headlight. The housing has a through cavity, which is divided into an inner cavity portion corresponding to the main housing portion and an outer cavity portion corresponding to the end cap portion. An installation port is provided on the side wall of the main housing. A pressure plate is sealed on the outside of the installation port. A PTC heater is fixedly installed on the inside of the pressure plate. A positive heat-conducting metal sheet and a negative heat-conducting metal sheet are tightly attached to the inside and outside of the PTC heater, respectively. A wire hole is provided on the pressure plate for the wire to pass through. The wire of the PTC heater is led out through the wire hole. A desiccant is contained within the inner cavity. Two screens are respectively disposed at both ends of the inner cavity, and are respectively close to the end of the main shell that extends into the headlight and the end of the inner cavity that connects to the outer cavity; A partition is fixedly installed inside the outer cavity. A snap-fit ​​hole is provided in the center of the partition, and multiple ventilation holes are evenly distributed around the outer ring of the snap-fit ​​hole. A rubber valve is snapped into the snapping hole, and the rubber valve can open or close the vent hole under the action of the air pressure difference between the inner cavity and the outer cavity. A waterproof and breathable membrane is welded to the outer end of the outer cavity.

2. The reversible moisture-absorbing structure for active defogging of vehicle lights according to claim 1, characterized in that, The cross-sectional area of ​​each vent hole in the partition is 0.19–7.06 mm². 2 .

3. The reversible moisture-absorbing structure for active defogging of vehicle lights according to claim 1, characterized in that, The hygroscopic agent is a superabsorbent polymer.

4. The reversible moisture-absorbing structure for active defogging of vehicle lights according to claim 1, characterized in that, The rubber valve is umbrella-shaped, including a rod portion that snaps into the snap-in hole and an umbrella portion that presses against the partition from the outside; the rod portion is inverted, with its free end extending to the inside of the vent and exposed; the inner side of the umbrella portion has a concave arc facing the vent, and the umbrella portion gradually thins from the inside to the outside, with a raised edge to accommodate the opening action driven by air pressure difference.

5. The reversible moisture-absorbing structure for active defogging of vehicle lights according to claim 1, characterized in that, A sealing ring is fitted at the mounting joint between the housing and the rear side of the headlight. The housing can be detachably installed on the back of the headlight by means of threaded connection or snap-fit ​​connection.

6. The reversible moisture-absorbing structure for active defogging of vehicle lights according to claim 1, characterized in that, The rubber valve is provided in two parts, which are snapped into the snap-fit ​​hole with opposite orientations.

7. The reversible moisture-absorbing structure for active defogging of vehicle lights according to claim 1, characterized in that, The venting opening pressure of the rubber valve is 0.5 to 5.8 kPa.

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