JPS645283Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lamp unit used in an automobile or the like, and particularly relates to a breathing structure of a lamp unit.

As is well known, in an automobile lamp unit, the pressure within the space surrounded by the reflector and lens changes significantly due to changes in internal and external temperatures, so a breathing tube 1 as shown in Figure 1 is attached. is normal. That is, in FIG. 1, the reference numeral 2 is a lens, and the reference numeral 3 is a reflector. A bulb 4 is removably attached to the mouth 3a of the reflector 3 via a base 5, and the outer circumference of the base 5 is covered with a sealing rubber. It is covered by 6. The same seal rubber 6 includes a lens 2 and a reflector 3.
A passage 8 is formed that communicates a space 7 surrounded by
(Refer to Utility Model Application No. 53-32585).

Therefore, according to such a structure, the pressure difference between the inside and outside caused by a temperature change is regulated through the breathing tube 1, but at the time of intake, outside air containing dust and moisture flows into the space 7. For this reason, dust and dew condensation on the inner surface of the lens may cause the lens to become damaged.
The light distribution characteristics of the lamp unit may be affected, and water droplets may accumulate inside the lamp unit, contributing to quality deterioration.

In view of the actual conditions of conventional lamp units as described above, the present invention is capable of regulating the pressure inside the lamp unit due to temperature changes, and is capable of automatically discharging water droplets accumulated inside the lamp unit to the outside without causing adsorption. A water drainage bag that can be expanded and contracted by changes in internal pressure is attached to the opening at the bottom of the lamp unit, and when the internal pressure rises, the slit at the bottom of the bag is pushed open to remove accumulated water droplets. This proposal proposes that the waste be discharged to the outside.

Embodiments of the present invention will now be described in detail with reference to FIGS. 2 and 3.

FIG. 2 is a diagram corresponding to FIG. 1 of the first embodiment of the present invention, and the same structural parts as in FIG. 1 are given the same reference numerals as in FIG. 1. The feature of the first embodiment is a rubber drainage bag 9 that is attached to an opening 3b formed in the bottom 3a of the reflecting mirror 3. This bag body 9 has an attachment opening 9a that is tightly fitted into the opening 3b, and a bellows 9b that can be freely expanded and contracted by changes in internal pressure is formed in the middle part of the attachment opening 9a, and a slit 10 is inserted in the lower end of the bellows 9b. A pair of lip-shaped one-way valves 9
c, 9d. It should be noted that in the embodiment shown in FIG. 2, no breathing passage is formed in the seal rubber 6 because breathing is not performed through the seal rubber 6.

Since the first embodiment has the above structure,
When the internal temperature of the lamp unit decreases, the bag body 9 bends as shown by the imaginary line to prevent a drop in internal pressure, so that no exhalation occurs into the lamp unit.
Furthermore, when the internal temperature rises due to lighting of the bulb 4, etc., the bag body 9 expands.
Since the internal air escapes from the slit 10 to the outside,
The inside of the lamp unit is maintained at approximately the same pressure as the outside world. In this case, since the water droplets condensed inside the lamp unit are collected at the bottom of the bag body 9, they are automatically discharged to the outside of the lamp unit together with the exhaled air mentioned above.

FIG. 3 is a view corresponding to FIG. 1 of the second embodiment of the present invention, and the features of the second embodiment include a draining bag 9A having a bulging portion and a bottom portion 3a of the reflecting mirror 3 having an inclined surface. be. That is, the middle part 9e of the bag 9A is a thin-walled bulge with an enlarged outer diameter, and the elastic deformation of the middle part 9e absorbs changes in the internal pressure of the lamp unit. Therefore, even with such a structure,
It is clear that the same effects as in the case of FIG. 2 can be obtained.

As is clear from the above explanation, according to the present invention, not only can the internal pressure of the lamp unit be kept constantly regulated, but also dust and moisture from the outside do not intrude into the interior, and even if Since a structure is created in which water droplets are automatically discharged to the outside, stable lamp performance can be ensured over a long period of time.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway side view of a conventional lamp unit, Fig. 2 is a side view corresponding to Fig. 1 of the first embodiment of the present invention, and Fig. 3 is a side view corresponding to Fig. 1 of the second embodiment of the present invention. FIG. 2...lens, 3...reflector, 4...bulb,
3b... (reflector) opening, 9, 9A... bag body, 9b... bellows (extensible part), 9e... thin walled bulge (extensible part), 10... slit.

Claims (1)

[Scope of utility model registration request] The bag is characterized in that an opening is formed at the bottom to communicate inside and outside, an expandable bag is attached to the opening, and a slit is formed at the bottom of the bag to discharge accumulated moisture to the outside when internal pressure increases. lamp unit.