A dehumidification and conduction defogging structure for vehicle lamp
By incorporating a defogging structure with water-absorbing resin and a PTC heater inside the headlights, efficient and continuous moisture removal is achieved, solving the problem of low headlight defogging efficiency and improving driving safety.
Patent Information
- Application Number
- CN202522383933.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-11
- Publication Date
- 2026-11-03
- Estimated Expiration
- 2035-11-11
AI Technical Summary
Existing headlight defogging methods are inefficient and cannot effectively remove moisture, affecting driving safety.
The demisting structure consists of a water-absorbing resin and a PTC heater inside the shell. The water-absorbing resin absorbs moisture and evaporates the moisture through a heat-conducting metal ring. The moisture is then discharged through a waterproof and breathable membrane, forming a closed-loop cycle of moisture absorption, conduction, and evaporation.
It quickly removes fog, continuously absorbs and expels moisture from inside the headlights, prevents fog from forming repeatedly, adapts to different car models, offers flexible installation, and has a long service life.
Smart Images
Figure CN224932565U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of vehicle headlight defogging technology, specifically, it relates to a vehicle headlight moisture absorption and conduction defogging structure. 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 housing is installed on the rear seat of the headlight and has a through cavity. The cavity has an inner cavity that extends into the rear seat of the headlight and an outer cavity that is located outside the rear seat of the headlight, and the volume of the inner cavity is greater than the volume of the outer cavity. The absorbent resin is disposed in the inner cavity, and fills both the inner and outer cavities, with a gap between it and the side wall of the outer cavity. A heat-conducting metal ring installed in the outer cavity and fitted with water-absorbing resin is connected to a PTC heater. A waterproof and breathable membrane is welded and sealed at one end of the outer cavity; A vent cap fixed to one end of the inner cavity; When the PTC heater is powered off, the water-absorbing resin in the inner cavity absorbs the moisture inside the headlight and conducts it to the outside of the headlight through the water-absorbing resin in the outer cavity; when the PTC heater is powered on, the PTC heater heats the heat-conducting metal ring, causing the moisture in the water-absorbing resin in the outer cavity to evaporate and be discharged to the outside of the headlight through the waterproof and breathable membrane.
[0006] According to one embodiment of the present invention, the water-absorbing resin is in granular form, and is wrapped with a cylindrical cover with sieve holes, which fills the inner cavity to ensure moisture absorption efficiency.
[0007] According to one embodiment of the present invention, the housing has a wire hole for leading out the wire of the PTC heater, and the wire is connected to the power plug; when the power plug is powered on, the wire connected to the PTC heater starts to heat up, gradually increasing the temperature of the heat-conducting metal ring, and the heat-conducting metal ring gradually heats the water-absorbing resin in the outer cavity, causing the water vapor to evaporate and finally be discharged outside the lamp through the waterproof and breathable membrane.
[0008] According to one embodiment of the present invention, the water-absorbing resin is a high molecular weight water-absorbing resin, which has high hygroscopicity and stability.
[0009] According to one embodiment of the present invention, the cross-sectional area of the absorbent resin in the outer cavity is 19-113 mm². 2 To optimize moisture conduction and evaporation efficiency.
[0010] According to one embodiment of this utility model, the PTC heater is a positive temperature coefficient thermistor heater, which has automatic temperature control characteristics and is safe and reliable.
[0011] According to one embodiment of the present invention, the waterproof and breathable membrane is a polytetrafluoroethylene breathable membrane, which has good waterproof and breathable properties.
[0012] According to one embodiment of the present invention, a sealing ring is provided at the mounting joint between the housing and the rear seat of the vehicle lamp. The housing is installed at any position on the back of the vehicle lamp by means of a thread or snap-fit structure, ensuring sealing and installation flexibility.
[0013] Compared with the prior art, the present invention can achieve the following technical effects: Through an active defogging mechanism that combines moisture absorption, conduction, and evaporation, it can not only quickly remove existing fog, but also continuously absorb and expel moisture from inside the headlights to prevent fog from forming repeatedly. At the same time, it is integrated into a single housing structure, making it flexible to install and adaptable to headlights of different models and locations. The superabsorbent polymer has a large moisture absorption capacity and excellent conductivity. The self-limiting temperature characteristic of the PTC heater ensures long-term stable operation. The service life of the entire structure is basically matched with the service life of the vehicle lights. The dual-seal design of the waterproof and breathable membrane and the sealing ring ensures that moisture can escape while preventing external water and dust from entering. At the same time, the self-limiting temperature characteristic of PTC avoids the risk of overheating.
[0014] 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
[0015] 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 front view of the vehicle lamp moisture-proof, breathable, and defogging structure according to an embodiment of this utility model; Figure 3 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.
[0016] Attached Figure Labels
[0017] Housing 10, rear seat of headlight 20, inner cavity 31, outer cavity 32, water-absorbing resin 40, heat-conducting metal ring 50, PTC heater 60, wire 61, power plug 62, waterproof and breathable membrane 70, breathable cover 80, sealing ring 90. Detailed Implementation
[0018] 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.
[0019] Please refer to Figures 1 to 3 , 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 front view of the vehicle lamp moisture-proof, breathable, and defogging structure according to an embodiment of this utility model; Figure 3 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.
[0020] As shown in the figure, a moisture-proof, breathable, and defogging structure for vehicle lights includes a housing 10. The housing 10 is installed on the rear seat 20 of the vehicle light via a threaded or snap-fit structure, adaptable to the installation requirements of vehicle lights of different models, and can be installed at any position on the back of the vehicle light. A sealing ring 90 is provided at the joint between the housing 10 and the rear seat 20 of the vehicle light. The sealing ring can be made of silicone and the compression rate is controlled at 20%-30% to ensure the airtightness of the inside of the vehicle light after installation, preventing the intrusion of external dust and liquid water.
[0021] The housing 10 is made of high-temperature resistant and aging-resistant modified engineering plastics, such as PA66+GF30. The housing 10 has a through cavity with an overall stepped cavity structure and a T-shaped cross-section. The cavity is divided into an inner cavity 31 and an outer cavity 32. The inner cavity 31 extends into the rear seat 20 of the headlight and occupies 60%-70% of the total volume of the cavity. Its port is sealed by a vent cover 80 made of PP with a porous cover structure and a porosity of ≥30% to allow water and air to circulate inside the headlight. The outer cavity 32 is located outside the rear seat 20 of the headlight and has a relatively smaller volume. Its end is equipped with a waterproof and breathable membrane 70 mounting position. The waterproof and breathable membrane 70 is laser-welded to achieve waterproof and breathable functions.
[0022] The superabsorbent polymer (SAP) 40 is made of granular superabsorbent polymer (SAP) and encased in a perforated cylindrical cover. This cover is made of high-temperature resistant plastic or sintered mesh to ensure packaging stability. It fills the cavity of the shell 10, leaving gaps between it and the shell wall to allow for moisture circulation. In the design, multiple positioning posts can be installed on the inner wall of the cavity to clamp the superabsorbent polymer 40's cylindrical cover and prevent excessive vibration and shaking. The moisture-absorbing section corresponds to the inner cavity 31, occupying the space within the cavity. It has a porous mesh structure with a specific surface area ≥ 500 m². 2 / g, capable of efficiently adsorbing moisture inside the headlights. The moisture-conducting section corresponds to the outer cavity 32, occupying the space of the outer cavity 32 of the cavity. It is a dense fiber conductive structure with continuous moisture conduction channels. The cross-sectional area of the moisture-conducting section is strictly controlled between 19-113mm². 2 , such as 19mm 2 50mm 2 113mm 2 Available in gradient specifications to accommodate varying moisture production levels in different vehicle lights. This absorbent resin 40 has a water absorption ratio ≥500 times (deionized water) and excellent moisture conductivity, rapidly transferring moisture from the inner cavity 31 to the outer cavity 32 after absorption. The absorbent resin 40, such as sodium polyacrylate, has a large moisture absorption capacity and can be reversibly used by desorbing moisture through heating.
[0023] The heat-conducting metal ring 50 is made of a metal material with high thermal conductivity (such as copper or aluminum-magnesium alloy) and is processed into an annular sleeve structure. It is sleeved on the outside of the moisture-conducting section of the outer cavity 32. The sleeve wall thickness is 1-2mm, and the gap between the inner wall and the moisture-conducting section is ≤2mm to ensure efficient heat transfer. In addition, the outer wall of the thermally conductive metal ring 50 is tightly bonded to the heating surface of the PTC heater 60 via thermally conductive silicone grease, with a contact thermal resistance ≤0.1℃・cm. 2 / W. The PTC heater 60 uses a positive temperature coefficient thermistor (PTC) heater with self-limiting temperature characteristics. Its operating temperature range is 80-120℃ (customizable according to vehicle lighting conditions), and its rated power is 5-15W. The electrodes of the PTC heater 60 are led out through high-temperature resistant wires 61 (such as fluororubber wires). Wires 61 pass through the wire holes in the housing 10 and connect to an external power plug 62, which is a standard automotive connector. The power plug 62 can be connected to the vehicle lighting power supply system, and can be turned on or off at appropriate times via a central control button.
[0024] The waterproof and breathable membrane 70 uses polytetrafluoroethylene (PTFE) breathable membrane, which has the characteristics of being breathable but not leaking water, with an air permeability of ≥5000g / m³. 2 • 24h (@25℃, 90% RH), waterproof rating ≥ IP67. It can be sealed to the end of the outer cavity 32 using laser welding technology, with a welding strength ≥ 5N / mm, ensuring that moisture can be discharged through the membrane layer while preventing external liquid water and dust from entering.
[0025] The working principle of this utility model is as follows: Power-off moisture absorption stage: When the PTC heater 60 is powered off, the moisture inside the headlight forms fog under the effect of temperature difference. The fog enters the moisture absorption section of the inner cavity 31 through the pores of the vent cover 80. The water-absorbing resin 40 quickly absorbs the moisture and conducts it to the moisture-conducting section on the outside. At this time, the moisture-conducting section of the outer cavity 32 is in the "moisture absorption and evaporation" state.
[0026] Evaporation stage: When the PTC heater 60 is powered on, the power plug 62 is connected to supply power. The current passes through the wire 61 to heat the PTC heater 60. The heat is quickly transferred to the moisture-conducting section of the outer cavity 32 through the heat-conducting metal ring 50. The moisture in the moisture-conducting section is heated and evaporated into water vapor. The water vapor is discharged to the external environment of the vehicle headlight through the micropores of the waterproof and breathable membrane 70.
[0027] The defogging cycle stage: The moisture absorption section inside the lamp continuously absorbs moisture and conducts it to the moisture conduction section. The moisture in the moisture conduction section is continuously heated and evaporated and discharged, forming a closed loop of "moisture absorption-conduction-evaporation-exhaust", thereby achieving continuous removal of moisture inside the headlight and solving the fogging problem from the root.
[0028] This utility model has been tested and found that when powered on, it can heat through the PTC heater 60 and conduct heat through the heat-conducting metal ring 50 within 8 minutes, evaporating the moisture in the water-absorbing resin 40 section of the outer cavity 32 and discharging it through the waterproof and breathable membrane 70. It can operate continuously for 3 years without performance degradation.
[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 moisture-absorbing and conductive defogging structure for vehicle lights, characterized in that, include: A housing, which is mounted on the rear seat of a vehicle headlight and has a through cavity, the cavity having an inner cavity portion extending into the rear seat of the headlight and an outer cavity portion located outside the rear seat of the headlight, and the volume of the inner cavity portion being larger than the volume of the outer cavity portion; The absorbent resin disposed in the inner cavity, the absorbent resin filling the inner cavity and the outer cavity, and having a gap with the sidewall of the outer cavity; A thermally conductive metal ring is installed in the outer cavity and fitted with the water-absorbing resin, and the thermally conductive metal ring is connected to a PTC heater. A waterproof and breathable membrane is welded and sealed at one end of the outer cavity; A vent cap fixed to one end of the inner cavity; When the PTC heater is de-energized, the water-absorbing resin in the inner cavity absorbs moisture from inside the lamp and conducts it to the outside of the lamp through the water-absorbing resin in the outer cavity; when the PTC heater is energized, the PTC heater heats the heat-conducting metal ring, causing the moisture in the water-absorbing resin in the outer cavity to evaporate and be discharged to the outside of the lamp through the waterproof and breathable membrane.
2. The vehicle headlight moisture absorption and conduction defogging structure according to claim 1, characterized in that, The water-absorbing resin is in granular form, and is wrapped with a cylindrical cover with sieve holes, filling the inner cavity.
3. The vehicle headlight moisture absorption and conduction defogging structure according to claim 1, characterized in that, The housing has a wire hole for leading out the wire of the PTC heater, which is connected to a power plug. When the power plug is powered on, the PTC heater starts to heat up, gradually increasing the temperature of the heat-conducting metal ring. The heat-conducting metal ring gradually heats the water-absorbing resin in the outer cavity, causing water vapor to evaporate and eventually be discharged outside the lamp through the waterproof and breathable membrane.
4. The vehicle headlight moisture absorption and conduction defogging structure according to claim 1, characterized in that, The water-absorbing resin mentioned therein is a superabsorbent polymer.
5. The vehicle headlight moisture absorption and conduction defogging structure according to claim 1, characterized in that, The water-absorbing resin in the outer cavity has a cross-sectional area of 19-113 mm². 2 .
6. The vehicle headlight moisture absorption and conduction defogging structure according to claim 1, characterized in that, The PTC heater mentioned above is a positive temperature coefficient thermistor heater.
7. The vehicle headlight moisture absorption and conduction defogging structure according to claim 1, characterized in that, The waterproof and breathable membrane mentioned therein is a polytetrafluoroethylene breathable membrane.
8. The vehicle headlight moisture absorption and conduction defogging structure according to claim 1, characterized in that, A sealing ring is provided at the mounting joint between the housing and the rear seat of the headlight, and the housing is installed at any position on the back of the headlight by means of threads or snap-fit structure.