JPS6310621Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sealed beam lamp, and more particularly to a sealed beam lamp in which a lens and a reflector are bonded together with an adhesive.

Conventionally, the lenses and reflectors of this type of sealed beam lamp have been welded type lenses and reflectors. That is, the shape of the welding type lens and reflector, each formed of glass into a corresponding desired shape and joined by heating and melting the peripheral edges of each lens, is as shown in FIG. a joint surface c having a protrusion d on the periphery of the
is formed, and a joint surface f having a protrusion g is formed at the periphery of the opening of the reflector e. When joining both members with adhesive h, the space formed between the protrusion g on the reflector e side and the protrusion d on the lens a side is filled with the adhesive h, as shown in Fig. An adhesive h is applied to the joint surface f of the reflector e, and the lens a is placed and pressed on the adhesive h to airtightly join the lens a and the reflector e. In this case, unless the space formed between the protrusions d and g is filled with the adhesive h, the adhesive strength will weaken due to the expansion or contraction of the air sealed in this space, making it impossible to maintain an airtight state. . In particular, this is a serious defect when applied to headlamps and the like that are used under severe temperature conditions. Therefore, the amount of adhesive h that fills the space is required to be about three times the amount set for the adhesive function. Also, adhesive h
Depending on the type of adhesive, if the bonding film thickness is not thin in the bonded state, it may not be possible to use a type of adhesive that cannot exhibit a strong adhesive function under severe temperature conditions, such as -40 to +80℃, depending on the space. become,
Furthermore, since there is a protrusion g on the joint surface f of the reflector e, it is difficult to uniformly apply the adhesive h. Moreover, the lens a and reflector e, which are formed by press-molding a glass lump dropped into a fixed mold with a movable mold, have protrusions d and g on the joint surfaces c and f, respectively, so the basic wall thickness is thick. This has the disadvantage that weight reduction cannot be achieved.

In view of the above circumstances, the present invention eliminates the need to use more adhesive than is necessary, allows the adhesive film thickness to be set arbitrarily, provides strong adhesion, allows the use of various adhesives, and prevents the reflector from being damaged due to adhesive extrusion. The object of this invention is to provide a new sealed beam type lamp that can prevent stains on the reflective surface.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

Figures 2 and 3 show an embodiment of the present invention, in which the reflector 1 and lens 2 are formed of glass into a corresponding desired shape, for example, a round or square shape when viewed from the front. On the inner surface of the reflector 1, a substantially paraboloid-shaped reflecting surface is formed by vapor-depositing aluminum or the like. The reflector 1 has a light source, although not shown. The light source may be a filament or a bulb supported by a plurality of metal inner supports embedded in the reflector 1, and the sealed beam type lamp of the present invention is designed so that the bulb can be attached and detached from the rear of the reflector 1. It may also be of the type that is held by the reflector 1. A flat joint surface 11 is formed at the periphery of the opening of the reflector 1 as shown in the figure.

The lens 2 consists of a lens surface 21 having a large number of prisms 21 formed on its inner surface, and a side wall leg 22 rising from the periphery of this lens surface 21. A flat cementing surface 23 is provided at the periphery of the side wall leg 22. is formed, and in this example, the joint surface 23 is inclined inward at an angle θ.

When bonding the reflector 1 and lens 2 formed in this way, the bonding surface 1 of the reflector 1 is
Adhesive 3 is applied to lens 1, bonding surface 23 of lens 2 is placed thereon, and lens 2 is pressed toward reflector 1. Then, as shown in FIG. 3, the outer tip of the bonding surface 23 of the lens 2 comes into contact with the bonding surface 11 of the reflector 1, forming a generally wedge-shaped space, and the adhesive 3 is applied to the inclined bonding surface 23 within the space. This will be expanded further. Therefore, it is preferable that the amount of adhesive 3 applied is such that it does not protrude inward in the bonded state. The required amount can be achieved by changing the inclination angle θ depending on the type of adhesive. Since the space formed by the contact does not become small, a stable bonding film thickness t can be ensured.

Moreover, the adhesive 3 that can be used in this example has a bonding film thickness t
Epoxy adhesive that becomes thick (uses a large amount),
It is possible to use various adhesives 3 such as ultraviolet curing adhesives with a thin bonding film thickness t, and in particular, when the adhesive 3 is an ultraviolet curing adhesive, the bonding film thickness t can be set to 1.5 mm. It is preferable to set the inclination angle θ to be as follows. According to the experimental results, when bonding the glass reflector 1 and lens 2, the ultraviolet curable adhesive 3 becomes adhesive when the adhesive film thickness t in the bonded state exceeds 1.5 mm and the temperature returns to room temperature from -40℃. 3, a crack occurred and the airtight state could not be maintained, but
No cracks occurred when the bonding film thickness t was set to 1.5 mm or less.

Since the joint surfaces 11 and 23 of the reflector 1 and the lens 2 are flat, that is, the protrusions d and g are not formed as in the conventional case, the glass material can sufficiently go around even if the material flow path in the entire mold is narrow. The wall thickness can be reduced, and the adhesive 3 can be applied uniformly over the entire circumference. Further, the inclined joint surface 23 is not limited to the above example, but may be one in which the joint surface 11 of the reflector 1 is inclined inward at an angle θ as shown in FIG. One in which the surface 23 is inclined outward, one in which the cemented surface 11 of the reflector 1 is inclined outward as shown in FIG. One in which the joint surfaces 23 and 11 of the reflector 1 are tilted toward both sides as shown in FIG. or with the joint surfaces 23 and 11 of the lens 2 and reflector 1 facing outward at an angle θ/2, respectively, as shown in FIG.
2 may be inclined. in this case,
In the case shown in FIGS. 9 and 10, the angle θ/2 is not necessarily required, and it is sufficient if the total angle of both the joint surfaces 11 and 23 becomes the required angle θ.

In the above embodiment, the reflector 1 and the lens 2 are made of glass, but the reflector may be made of synthetic resin or metal, and the lens 2
may be a translucent synthetic resin such as polycarbonate or acrylic.

As is clear from the above embodiments, in the sealed beam lamp according to the present invention in which a lens and a reflector are bonded together with an adhesive, each bonding surface of the lens and reflector is formed flat, and at least one bonding surface is connected to the other bonding surface. Since it is characterized by being inclined with respect to the joint surface, the adhesive applied in a set amount is pushed out by the inclined joint surface, but it is pushed further than necessary due to contact. This prevents the protrusion from staining the reflective surface of the reflector. Moreover, by changing the angle of inclination of the joint surfaces, it is possible to use various adhesives, and it is possible to obtain sealed beam type lamps with stable quality that can maintain sufficient airtightness even under severe temperature conditions due to strong adhesion. can.

[Brief explanation of the drawing]

Fig. 1 shows a conventional example, in which Fig. A is a cross-sectional view of the main part before joining, and Fig. B is a cross-sectional view of the joined state of Fig. A. Figures 2 and 3 show an embodiment of the present invention, Figure 2 is a sectional view of the main parts before joining, Figure 3 is a sectional view of the joined state of Figure 2, and Figures 4 to 10 are FIG. 3 is a cross-sectional view showing a modification of the first embodiment of the present invention; 1...Reflector, 11...Joint surface, 2...
Lens, 23... Bonded surface, 3... Adhesive, θ...
Inclination angle, t...bonding film thickness.

Claims (1)

[Scope of utility model registration request] In a sealed beam lamp formed by bonding a lens and a reflector with an adhesive, each bonding surface of the lens and reflector is formed flat, and at least one bonding surface is inclined with respect to the other bonding surface. A sealed beam lamp featuring: