JPH0544962Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a ventilation system for preventing fogging of various indicator lights installed in automobiles.

(Prior Art) Indicator lights for automobiles are constructed by, for example, as shown in FIG. 4, a transparent plate 2 with a reflector is provided on the front surface of a housing 1, and indicator lamp units 3 and 4 are attached to this. has been done.

The lamp chamber 5 formed inside the indicator lamp is sealed with a sealing member to prevent moisture, dust, etc. from entering.

However, it is impossible to completely seal the lamp, and air containing moisture and dust that enters through the lead wires 6a and 7a connected to the lamp sockets 6 and 7 accumulates in the lamp chamber 5, and the air is heated when the lamp is turned on, and the transparent plate 2
This may cause water droplets to adhere to the lamps 6 and 7, causing fogging and reducing the display effect, as well as inducing electrical failures such as short circuits and poor insulation.

Therefore, in the conventional indicator lamp of this type, the lamp chamber 5
A nozzle 8 with communication between the inside and outside is integrally molded with the housing 1, and a hollow tube 9 made of rubber and curved in a U-shape is fitted into the nozzle 8 for ventilation.

That is, in this device, moist air expanded by heating is discharged to the outside through the nozzle 8 and tube 9 to prevent fogging.

(Problems to be solved by the invention) However, in the conventional ventilation device described above,
Since the communication path is constant and has a large diameter, moisture and dust constantly enter from the outside, and especially when the lamp is turned off and the inside of the lamp chamber 5 is cooled, a large amount of air containing moisture and dust from the outside enters and accumulates. Therefore, there was a drawback that water droplets could not be disposed of in a short time when the lamp was turned on. In addition, although measures have been taken to prevent water from entering during car washing, such as by making the vehicle U-shaped and providing a shielding plate 10 at the bottom, there is still a drawback that water cannot be completely prevented from entering.

Therefore, the present invention provides an anti-fog ventilation device that improves these drawbacks of the conventional type.

(Means for Solving the Problems) The gist of the present invention is that two nozzles are provided on the back side of the housing forming the lamp chamber to communicate the inside and outside of the lamp chamber for ventilation. Fitted into the nozzle is an exhaust tube that is normally closed and has a slit-like passage that opens when the pressure inside the lamp chamber becomes higher than the outside pressure, releasing the differential pressure to the outside. and the other nozzle has a slit-like passageway that is normally closed and opens when the pressure inside the lamp chamber becomes lower than the external pressure, allowing the differential pressure to flow in from the outside. This is an anti-fog ventilation system with a tube fitted into it.

(Example) An example of the present invention will be described below with reference to FIGS. 1 to 3. As in the conventional example, a transparent plate 12 is attached to the front side of the housing 11, a lamp chamber 13 is formed inside, and a lamp socket 14 is attached to the back side to form an indicator light.

Note that the reference numeral 14a in the figure is a lead wire connected to the lamp socket 14, and a lamp unit is connected to the lamp socket 14 in the same manner as in the conventional example described above, but is omitted in this figure.

A lamp chamber 1 is provided on the back side of the housing 11.
Two nozzles 1 each communicating between 3 and the outside.
5 and 16 are each integrally molded with the housing 11. One of the nozzles 15 projects outward from the housing 11, and the other nozzle 16
One end 16a projects from the housing 11 to the outside, and the other end 16b projects into the lamp chamber 13.

For each of the nozzles 15 and 16, an exhaust tube 17 is fitted and attached to the end of the nozzle 15 that protrudes from the housing 11 to the outside, and the other nozzle 16 protrudes into the lamp chamber 13. The other end 16
An intake tube 18 is fitted and attached to b. These tubes 17 and 18 are made of a relatively soft rubber material, and have large diameter cylindrical portions 17a and 18a formed on one side that is fitted into the nozzles 15 and 16, and the other side that is gradually reduced in diameter. Rectangular flat part 1
7b and 18b are formed. This flat part 17
Inside the b and 18b sides, narrow passages 17c and 18c are formed whose inner wall surfaces are in close contact with each other at all times, and the passages 17c and 18c create a pressure difference between the inside and outside of the lamp chamber 13. , the material etc. are set so that it expands accordingly.

Note that the passages 17c and 18c are cut using a thin and sharp blade such as a razor blade.

According to the above configuration, when there is no pressure difference or temperature difference between the inside and outside of the lamp chamber 13, such as when the lamp is turned off, the passages 17c and 18c of the tubes 17 and 18 are closed, so that moisture and moisture from outside are blocked. Infiltration of dust is prevented. Furthermore, when the temperature inside the lamp chamber 13 rises above the outside air due to lighting of the lamp, the expanded warm air inside the lamp chamber 13 sequentially flows out through the passage 17c of the exhaust tube 17, which expands due to the pressure difference. At the same time, when the air in the lamp chamber 13 becomes diluted due to the outflow of air, cold air from outside is exchanged into the lamp chamber 13 via the passage 18c of the intake tube 18, which expands due to the pressure difference. The so-called ventilation effect is performed by flowing into the air.

In this way, ventilation is always performed to reduce the pressure and temperature differences between the lamp chamber 13 and the outside, and even if the air flowing in at this time contains external dust or moisture, most of the Slit-like passage 1
8c and prevents it from entering the lamp chamber 13, and even a small amount of moisture in the air is immediately heated and vaporized and assimilated, thereby preventing fogging from forming inside the lamp chamber 13. can.

In addition, a filter may be attached to one end 16a of the nozzle 16, which has an intake tube 18 attached to the other end 16b, to further prevent the inflow of moisture and dust, or a curved tube 19 may be attached as in the conventional example. By doing so, it is possible to further reduce the direct intrusion of water during car washing and the like.

(Effects of the invention) As is clear from the above-mentioned embodiments, the ventilation system of the invention has tubes for exhaust and intake each having a slit-like passage that is normally closed and expands due to the pressure difference. As a result, ventilation is always performed to reduce the pressure and temperature differences between the lamp chamber and the outside, making it difficult for moisture and dust to enter the lamp chamber from the outside, and preventing the expanded air inside the lamp chamber from entering the lamp chamber. Due to the rapid release, the anti-fogging effect in the lamp chamber is significantly improved. In other words, when the warm air inside the lamp chamber expands due to a rise in temperature when the lamp is lit, it is discharged to the outside through the exhaust tube.
As a result, cold air flows into the lamp chamber from the outside via the intake tube, where the pressure has been reduced, thereby providing ventilation.

This eliminates the temperature and pressure difference between the inside and outside in a short time, and the moisture that has flowed in also touches the warm air inside the lamp chamber and evaporates immediately, lowering the internal temperature at the same time, significantly improving the anti-fogging effect. Ru. However, since each passage between the exhaust tube and the intake tube has a slit-like shape that opens instantly due to the differential pressure,
The expanded warm air inside the lamp chamber is rapidly released, and there is little moisture or dust entering the lamp chamber from the outside, which also contributes to preventing fogging.

[Brief explanation of the drawing]

Fig. 1 is an overall plan view, partially cut away, of an indicator light equipped with a ventilation system according to an embodiment of the present invention, Fig. 2 is a perspective view of the main parts of the ventilation system, and Fig. 3 is the same ventilation system. FIG. 4, which is a cross-sectional view of the device, is an overall perspective view of an indicator light using a conventional ventilation device. Explanation of symbols, 11... Housing, 12... Transparent plate, 13... Lamp chamber, 14... Lamp socket, 15, 16... Nozzle, 17, 18, 19...
...Tube, 17a, 18a...Cylindrical part, 17
b, 18b... flat part, 17c, 18c... passage.

Claims (1)

[Scope of Claim for Utility Model Registration] A ventilation device that communicates the inside and outside of a lamp chamber of an automobile indicator light to prevent the inside from fogging; Two nozzles are provided to communicate ventilation between the inside and outside, and one of the nozzles is normally closed, and when the pressure inside the lamp chamber becomes higher than the outside pressure, it opens and releases the differential pressure to the outside. An exhaust tube with a slit-like passage for discharge is fitted into the other nozzle, which is normally closed and opens when the pressure inside the lamp chamber becomes lower than the outside pressure, thereby reducing the differential pressure. An anti-fog ventilation device characterized by being fitted with an intake tube having a slit-like passage through which air flows in from the outside.