JPS6057161B2 - headlights - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a headlamp, and more particularly to a headlamp for an automobile, which has a lens provided on the front surface of a housing having a paraboloid-shaped reflective surface portion so as to be inclined with respect to a vehicle body mounting surface. It concerns headlights.

For this kind of thing, the lens of conventional headlights is usually the first
As illustrated in the figure, a fixed mold A is fixed to a rotary table (not shown), a ring mold B moves up and down with a constant stroke, and a ring mold B slides inside the ring mold and moves up and down with a constant stroke. A side wall part c is provided to extend the outer periphery of the front part by a flancher C, and a flange part d is provided at the edge of the side wall part c to form a lens a.
is formed by press-molding a glass lump inside the cavity.

And the parting line PL is horizontal,
The side wall c of the lens a needs to be sloped by the die-cutting angle α, and the thickness L of the flange d formed at the edge of the side wall c on the side of the ring mold B is parallel to the parting line PL. Because it is set, it is formed in a constant manner. Lens a molded as described above has been used in recent years for automobile design.
Alternatively, due to various reasons such as air resistance and increasing size to irradiate a wide area, the bulb is inserted through the bulb holder through the rear opening of the housing e, which has a paraboloid-shaped reflective surface part f, as shown in Figure 2. A headlamp is attached to a vehicle body (not shown), in which a flange part d provided on a side wall part c of a lens a formed as described above is adhered to the periphery of the front opening of the housing e in which the lens g is disposed. In recent years, the lens a has come to be installed in an inclined state with respect to the vehicle body surface D.

However, if the lens a formed as described above is used, for example, when mounted on a car body, if the lens a is installed at an angle γ with respect to the car body surface D, the lens a will be Coupled with the die-cutting angle α of the side wall c during molding, the side wall 'c is inclined at an angle β as shown in the figure, that is, the angle β becomes an inclination angle of (γ+α).

Therefore, among the light rays from the bulb g that are effectively reflected by the reflective surface part f, the rays that are incident on the side wall part c that is more inclined than necessary (reflected light rays in the part indicated by X in the figure) are reflected in the ineffective part. Z, the effective light emitting surface of lens a (the part indicated by Y in the figure) decreases, which reduces the effective utilization rate of the reflected light rays, resulting in disadvantages such as not being able to secure proper light distribution characteristics. be. Therefore, ideally, as shown in Fig. 3, the lens a'' is attached to the vehicle body surface at an angle γ, and the parting line is inclined at an angle γ. Since the side wall portion c is inclined by the die-cutting angle α when the “a” is attached to the vehicle body, the occurrence of an ineffective portion can be minimized. However, such a method of forming the lens a'' cannot currently be adopted.

This is because the fixed mold A is a rotary table (not shown).
Since it is fixed around the rotary table and rotates together with the table, the center of the rotary table is eccentric due to installation errors of the rotary table, etc. Also, multiple fixed molds A are fixed to the rotary table, and each fixed mold Since it is impossible for A to be fixed at the same radius, when the table is rotated, each fixed mold A will be set at a fixed position, but will shift in the left and right direction. Furthermore, since the ring mold B and the plunger C move up and down with a constant stroke, if the fixed mold A shifts in the left and right direction, the fixed mold B will not come into contact with the ring mold B. Gaps are created and burrs are generated.
Further, since a gap is formed in the plunger C more than necessary, there are disadvantages such as the basic wall thickness of the side wall part c and the front part b being different. The present invention was made in view of the above-mentioned circumstances, and in particular, in a headlamp in which the lens is attached at an angle when attached to a vehicle body, the lens is formed using the current molding method and the molding angle is molded in the same way as before,
Moreover, it prevents the side wall from being tilted more than necessary when installed, and it also prevents reflected light! It is an object of the present invention to provide a headlamp equipped with an ideal lens that can increase the effective light emitting surface of the lens and increase the effective utilization rate.

Embodiments of the headlamp according to the present invention will be described below with reference to the accompanying drawings.

The illustrated examples of FIGS. 4 and 5 are examples of the present invention, in which 1 is a lens, and this lens 1 includes a front part 10 having a prism part on its inner surface, and a side wall part 11 on the outer periphery of this front part 10.
A flange portion 12 is formed at the edge of this side wall portion 11.

The housing 2 has a reflecting surface section 3 shaped like a paraboloid of revolution, and a bulb holder 5 is disposed at the rear opening of the housing 2 so that the bulb 4 is positioned on the lamp axis E of the reflecting surface section 3. The flange portion 12 of the lens 1 is disposed around the opening of the housing 2 so as to be inclined at an angle γ with respect to the vehicle body mounting surface D, as shown in FIG. More specifically, the lens 1 is molded using the current lens molding method, as shown in FIG.

That is, a fixed mold A fixed on a rotary table (not shown), a ring mold B that moves up and down with a constant stroke, and a plunger that slides inside the ring mold B and moves up and down with a constant stroke. A glass gob is press-molded in the cavity defined by 1-C, or in the case of heat-resistant resin, it is injection-molded to form a front part 10 and a side wall part 11 on its outer periphery at an angle α of the mold. A lens 1 is molded, which is provided with a flange portion 12 on its edge. The parting line PL between the fixed mold A and the ring mold B is set horizontally in order to keep the basic thickness of the side wall part 11 and the front part 12, which has a prism part on the inner surface, constant. Furthermore, the flange portion 12 formed on the edge of the side wall portion 11 on the side of the ring mold B has an inclination angle of 0 sequentially from one end (right side in the figure) to the other end (left side in the figure).
It is formed by attaching a wall and changing the wall thickness.
That is, the projecting height of the flange portion 12 is gradually adjusted to zero inclination angle from the lower flange portion 12b of the lower side wall portion 11b, which is inclined by the die-cutting angle α of the side wall portion 11, toward the upper flange portion 12a. It is designed to grow larger.

When the headlight equipped with the lens 1 configured as described above is mounted on the vehicle body, the lens 1 is tilted by an angle γ with respect to the vehicle body mounting surface D as shown in FIG. If the lens 1 is molded by the lower side wall 11b, the mold removal angle α will be inclined, but the ring mold B side flange 12 will gradually reduce its thickness from the lower flange 12b to the upper flange 12a. Since the lens 1 is tilted at an angle of 0 to increase the thickness, the lower side wall portion 11b of the lens 1 is tilted at an angle β'' as shown.

This means that the angle β'' is an inclination angle of (γ0α10θ), and the conventional β and the present invention's β'' are β>β'', and the smaller β'' is, the larger the effective light emitting surface Y of the lens is. be able to. For example, if the inclination angle γ of the lens 1 is 15 with respect to the vehicle body mounting surface D, the lower side wall portion 11b of the lens 1 is
When the die cutting angle α=5, the necessary inclination angle β of the lower side wall portion 11b when the car body lens 1 is attached becomes β=20, but the lower flange portion of the flange portion 12 on the ring mold B side When the protrusion height of the flange portion is gradually increased from the upper flange portion 12b to the upper flange portion 12a with an inclination angle of 0 and the wall thickness becomes deeper, and the inclination angle θ of the wall thickness of the flange portion 12 is set to θ = 3. , β″=17 slope, and Sin2OO/
When Sinl7 = 1.17, the effective area of the lens increases by 17%. Therefore, when this lens 1 is attached to the vehicle body mounting surface D, the lower side wall portion 11b has a die cutting angle γ as in the conventional case.
Even if this is set, the depth of the wall thickness is increased from the lower flange portion 12b to the upper flange portion 12a so as to be inclined at an angle θ, so that the negative amount will be absorbed by the inclination angle θ. Since the reflected light from the reflective surface part 3 can be used more effectively, the ineffective area caused by the lower side wall part 11b of the lens 1 can be reduced, and the parting line is horizontal during molding. Conventional manufacturing techniques can be used without any burrs, and the thickness of the side wall and front surface can be made constant, so yields can be kept the same. still,
In the above embodiment, the lens of the headlight is tilted in the ± direction, but the present invention is not limited to this.
The effects of the present invention can be achieved even when the lens is tilted downward or the like.

As is clear from the above-described embodiments, the headlamp of the present invention includes a housing having a paraboloid-shaped reflective surface portion, and a lens disposed on the front surface of the housing so as to be inclined with respect to the vehicle body mounting surface. The lens is formed by molding a front surface, a side wall extending around the outer periphery of the front surface, and a flange on the edge of the side wall using a fixed mold, a ring mold, and a plunger. The parting line is horizontal, and the flange portion on the ring mold side has a wall thickness that changes so as to gradually increase the inclination angle from one end to the other end. When the lens is mounted on the car body mounting surface in an inclined state, even if the die cutting angle is set on the side wall as in the conventional case, the thickness of the flange on the ring mold side will change from one end to the other. Since the depth is formed at a large angle, the angle of inclination of the side wall part in the attached state is absorbed by that inclination angle and becomes negative, so the reflected light from the reflective surface part can be used more effectively.
The ineffective portion caused by the side wall portion can be reduced, and the effective light emitting surface of the lens can be enlarged to ensure appropriate light distribution characteristics.

In addition, during molding, the parting line is set horizontally, so burrs and basic wall thickness can be kept constant.
Furthermore, since conventional manufacturing techniques can be used as is, yields and the like can be kept the same.

[Brief explanation of the drawing]

Figures 1 and 2 show a conventional headlamp, Figure 1 is a longitudinal cross-sectional view showing the lens molding method, and Figure 2 is a headlamp with the lens attached to the vehicle body mounting surface with the lens tilted. FIG. FIG. 3 is an explanatory diagram showing an ideal method for molding a lens. Figures 4 and 5 show the headlamp of the present invention, Figure 4 is a longitudinal cross-sectional view showing the method of forming the lens, and Figure 5 is a headlamp with the lens mounted on the vehicle body mounting surface in an inclined state. FIG. 1... Luns, 10... Front part,
11...Side wall part, 12...Flange part, 2...Housing, 3h...Reflecting surface part shaped like a paraboloid of revolution, A...・Fixed mold, B...
...Ring mold, C...Plunger, D...
... Vehicle mounting surface, γ ... Angle of inclination of the lens with respect to the vehicle body mounting surface, α ... Cutting angle of side wall part, θ ... Inclination of flange part angle, β, β″
...The angle of inclination of the side wall of the lens when it is attached to the vehicle body.

Claims (1)

[Claims] 1. A housing having a paraboloid-shaped reflective surface portion, and a lens disposed on the front surface of the housing so as to be inclined with respect to the vehicle body mounting surface, and the lens includes a fixed mold, a ring mold, and a plunger. By forming a front part, a side wall part extending around the outer periphery of the front part, and a flange part at the edge of the side wall part, and making the parting line horizontal,
The headlamp is characterized in that the flange portion on the ring mold side is configured so that its wall thickness changes so as to gradually increase the inclination angle from one end to the other end.