JPS6238255Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a synthetic resin lamp reflector mainly used in automobile headlamps, photo lamps, and the like.

Conventionally, this type of synthetic resin lamp reflector has been made of polycarbonate resin to form a single-layer reflector base whose inner surface is approximately a paraboloid of revolution, and a reflective coating has been applied to the inner surface. Ta.

However, in a lamp reflector with this structure, the temperature of the reflector itself rises due to the incandescent bulb installed inside, especially the halogen bulb with a high calorific value, and the reflector itself becomes softened or deformed from about 130℃, which causes rotational release of the inner surface. There is a problem in that the state of the object surface is deformed, causing diffused reflection and reducing the illumination effect.

Therefore, the reflector base is molded with a composite resin material in which glass fiber is mixed with polycarbonate resin in order to strengthen it. Therefore, the inner surface must be undercoated with an amino-alkyd resin material, and a reflective coating must be formed on the undercoat, which requires many manufacturing steps and is complicated. It has the disadvantage of increasing costs. In addition, if this undercoat is made thick, cracks are likely to occur, so it has to be made thin, and for this reason, it is still not possible to eliminate unevenness on the inner surface of the reflector base, and conversely, uneven coating of the undercoat and There was a risk of causing blistering, and it was not possible to completely prevent diffused reflection.

This idea was devised in view of the above circumstances, and its purpose was to make it easy to manufacture and reduce costs, as well as improve heat resistance, rigidity, and smoothness, and to apply a reflective coating directly to the inner surface. The object of the present invention is to provide an extremely good illumination effect without causing diffused reflection due to unevenness or the like.

In order to achieve the above objectives, this invention
In a synthetic resin lamp reflector whose inner surface is a paraboloid of revolution, the reflector base is made of an inner layer molded from polybutylene terephthalate resin and a composite resin material made of polybutylene terephthalate resin mixed with reinforcing filler such as glass fiber. It has a multilayer structure consisting of a molded outer layer or an intermediate layer, and is characterized in that a reflective coating is applied directly to the inner surface of the inner layer of the reflector base.

An embodiment of this invention will be described below with reference to FIGS. 1 and 2. First of all, Figure 1 shows a rectangular headlight for automobiles in which the bulb is replaced at the rear, and 1 in the figure shows the synthetic resin lamp reflector of this invention, which is shaped into an approximately paraboloid of revolution. , 2 is its reflector 1
A halogen bulb is mounted inside the rear opening by being removably pressed and held by a spring 4 via a holder 3, and 5 is a transparent synthetic resin such as glass or polycarbonate provided at the front end of the reflector 1. It is a lens of.

As shown in FIG. 2, the synthetic resin lamp reflector 1 has a reflector base 6 having an inner/outer double layer structure as shown by 6a and 6b, and a reflective coating 7 on the inner surface of the inner layer 6a. is constructed by being directly applied. Further described later, the inner layer 6a of the reflector base 6 is made of polybutylene terephthalate resin (hereinafter referred to as polybutylene terephthalate resin).
It is made of PBT resin (abbreviated as PBT resin).
The outer layer 6b is made of a composite resin material in which reinforcing filler such as glass fiber or inorganic filler is mixed into the PBT resin. The molding method is, for example, an insert molding method in which the inner layer 6a is first molded, and then the molded product of the inner layer 6a is inserted into a mold for molding the outer layer to mold the outer layer 6b. Or, first the inner layer 6 is formed using a two-color molding machine.
It is manufactured using a two-color molding method in which the outer layer 6b is molded by molding the outer layer 6b by molding the outer layer 6b by rotating the mold. At this time, the outer layer 6b
The amount of reinforcing filler mixed into PBT resin is 20 to 40
% is best because it is easy to mold and provides appropriate rigidity (strength). In addition, as mentioned above, the inner and outer layers 6
The reflective coating 7 on the inner surface of the inner layer 6a of the reflector base 6 manufactured by molding a and 6b is a highly reflective coating 7 by depositing aluminum or the like by a vacuum evaporation method, a sputtering method, or an ion brazing method. is formed directly.

The lamp reflector 1 having the above-mentioned structure has a reflector base 6 having a double layer structure, an inner layer and an inner layer, and an inner layer 6b.
Since the outer layer 6b is made of a composite resin material made of PBT resin mixed with reinforcing filler, the inner surface of the PBT resin inner layer 6a has good smoothness and gloss, and is coated with an undercoat. It is possible to provide the reflective coating 7 by direct vapor deposition etc. without
This results in an excellent optical reflection effect,
At the same time, since the PBT resin thermal deformation temperature is 180° C., the inner layer 6a has excellent heat resistance, and there is no softening or deformation due to the heat of the halogen bulb 2, and there is no possibility of diminishing the illumination effect such as diffused reflection. On the other hand, PBT
The outer layer 6b, which is made of a composite resin material containing a reinforcing filler, has high rigidity and improves the overall strength of the reflector base 6. At the same time, it has excellent chemical resistance compared to polycarbonate, and is durable even after repeated car washes. This eliminates the possibility of deterioration over a long period of time. Therefore, a smooth reflective coating with excellent rigidity (strength), heat resistance, and durability and no diffused reflection can be applied, resulting in an extremely excellent lighting effect.

Furthermore, in its production, the inner and outer layers 6a and 6b of the reflector base 6 can be easily molded, and the reflective coating 7 can be applied directly to the inner surface of the reflector base 6, thereby omitting the conventional undercoating process. Manufacturing is easy and costs can be reduced.

Figure 3 shows another embodiment of this invention.
Here, the reflector base 6 is an example of a three-layer structure of inner, outer and intermediate layers as shown by 6c, 6d, and 6e.
The inner layer 6c is molded from PBT resin in order to obtain smoothness and heat resistance as in the previous embodiment, the intermediate layer 6d is molded from a composite resin material in which a reinforcing filler is mixed into PBT resin to obtain rigidity, and the outer layer 6e is the above inner layer 6
It is molded from the same PBT resin as c. The reflective coating 7 is applied directly to the inner surface of the inner layer 6c by vapor deposition, as in the previous embodiment.
d and 6e are formed by forming the inner and outer layers 6c and 6 as described above.
Since e is molded from the same resin material (PBT resin),
The Sand Deutsch molding method can be applied. That is, first, the PBT resin for the inner and outer layers is injected into the mold, and then the composite resin material for the intermediate layer is injected into the PBT resin.
c, 6d, and 6e can be molded in the same mold in a short time. This makes manufacturing easier and reduces costs, while at the same time improving rigidity and
An excellent reflector that satisfies all aspects such as heat resistance and smoothness can be obtained.

Note that the outer layer 6b in the case of the double layer and the middle layer 6d in the case of the triple layer can be made of recycled material as a composite resin material, thereby reducing product cost.

As detailed above, this idea is easy to manufacture, reduces costs, and at the same time improves heat resistance, rigidity, and smoothness, and eliminates diffuse reflection due to unevenness even when a reflective coating is applied directly to the inner surface. A synthetic resin lamp reflector with good lighting effects can be obtained.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a synthetic resin lamp reflector applied to a car headlight, showing one embodiment of this invention; Figure 2 is an enlarged cross-sectional view of section A in Figure 1;
This figure is an enlarged sectional view similar to FIG. 2 showing another embodiment of this invention. DESCRIPTION OF SYMBOLS 1... Synthetic resin lamp reflector, 6... Reflector base, 6a, 6c... Inner layer, 6b, 6e... Outer layer, 6d... Intermediate layer, 7... Reflective coating.

Claims (1)

[Scope of utility model registration request] In a synthetic resin lamp reflector whose inner surface is approximately a paraboloid of revolution, the reflector base is made of an inner layer made of polybutylene terephthalate resin, and a composite material made of polybutylene terephthalate mixed with a reinforcing filler such as glass fiber or inorganic filler. No multilayer structure consisting of an outer layer or an intermediate layer molded from resin material,
A synthetic resin lamp reflector characterized in that a reflective coating is directly applied to the inner surface of the inner layer of the reflector base.