JPS6231761B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to headlamps, particularly automotive headlamps, and more particularly to optical blocks thereof.

An optical block is essentially two parts: a reflector with at least one light bulb that optically cooperates with the reflector, and a light beam delivered by the reflector arranged on the front aperture of the reflector. A combination body that includes a glass plate that diffuses

In current optical blocks, the glass plate parts and the reflector parts are joined together along their peripheral connections with an adhesive material preferably formed of an epoxy resin forming an assembly adhesive.

In a preferred embodiment for doing this, one of the two parts has a peripheral groove or peripheral flange that cooperates with the peripheral edge of the other part. An example of this type of structure is French Patent No. 1405235 owned by Sivier Prodjiector.

Large diameter optical blocks manufactured to date, particularly those for automobile headlights, traditionally have a glass plate and a reflector made of a pressed metal plate. These two materials have very similar coefficients of thermal expansion and adhesive assembly of these two parts did not present any particular problems.

With the development of technology for reflective mirrors made of plastic materials, it is now possible to manufacture large diameter reflective mirrors by molding plastic materials that are as satisfactory in terms of optical design as conventional metal reflective mirrors. In order to make an optical block from this type of reflector made of plastic material, even if molding technology makes it possible to produce it, it is necessary to use the shape of a conventional metal reflector, especially its end part, flange part, which cooperates with the glass plate. , it is natural to use a reflecting mirror having a peripheral groove.

According to numerous tests conducted by the present inventor, optical blocks made in this manner have a small but statistically distinct effect when mass-produced.
It has been confirmed that significant defects occur.
In particular, cracks and breakages of plastic reflectors have been noted, leading to a lack of tightness of the glass pane and reflector assembly, and in other cases.
The coupling connection between these two parts will be incomplete.

As a result of the investigation, it was found that this type of phenomenon is largely caused by differences in thermal expansion. One of the problems is
One is the difference in thermal expansion that occurs between the two parts in the case of changes in the outside temperature to which they are subjected, and the other is the difference in expansion within the reflector itself due to the heating of the light bulb attached to the reflector during use. This is because each region of the mirror experiences a different temperature rise.

The present invention thus provides a simple and effective solution to this problem of properly utilizing the finished technique of shaping reflectors with plastic material.

According to the present invention, the circumferential shapes (ends, flanges, circumferential grooves, etc.) of two parts that play a role in assembly have a considerable size that is intentionally created between them. Furthermore, each part to be assembled has a male-female precision mold that cooperates so that the two parts are accurately centered relative to each other to ensure accurate centering. It has a mechanism in which the material for assembly is consolidated.

The present invention will be explained below with reference to the accompanying drawings.

The optical block of the present invention has a reflector 10 made of plastic and a glass plate 20 made of glass. For assembly purposes, the reflector 10 has a first wall 1 approximately parallel to the aperture of the reflector for assembly purposes.
1a and a second wall 11b substantially perpendicular to the opening. Wall part 11b
has an assembly opening with an inner diameter D1. Aside from that,
The glass plate 20 has an enclosed flange 21 for assembly, the outer diameter D2 of which is considerably smaller than D1. For example, the difference between D1 and D2 may be 0.5 to 3 millimeters.

Characteristically, the reflector 10 has an embossed centering projection 16 located at its periphery and molded therewith. What is noteworthy is that
This type of embossment is virtually impossible to create with pressed metal reflectors. The glass plate has a similarly shaped groove 26 on one side thereof. Projection part 1
6 and the groove 26 work together by fitting without any play to enable proper centering of the glass plate 20 with respect to the reflector 10, and the flange portion 21 of the glass plate
The external contour of is centered completely within the internal contour of the reflector flange 11b. In this position, an adhesive material, for example an epoxy resin, is introduced in liquid form between the two parts (before or after so-called mounting), and this adhesive solidifies and fixes the assembly in its position. The number 30 indicates this adhesive.

It has been confirmed that the optical block according to the invention obtained as described above does not exhibit any vulnerability to overall or local temperature changes after the adhesive has solidified.

As mentioned above, the centering female and female mechanisms (such as the projections 16 and grooves 26) are preferably located on two orthogonal diameters of the aperture ring of the headlamp. Further, as shown in the drawings, it is preferable to form a substantially truncated cone shape or a truncated pyramid shape (truncated pyramid shape) to enable successive fitting.

FIG. 3 is a perspective view to clarify the assembly of the front glass plate and the reflector, and this assembly is performed in the direction of arrow 100.

The same reference numerals as in FIGS. 1 and 2 are used here.

The present invention is not limited to the embodiments described above, and all types of inset assembly (end, flange,
peripheral grooves, etc.), each with two
It can be used for any of the individual parts. The same applies to the centering mechanism.

Finally, it should be noted that in some cases, the centering mechanism is used during all assembly when the parts, due to their general shape, can be assembled in several positions, only one of which is correct. Correct your mistakes in a useful way
It is to play the role of

Furthermore, when an optical block according to the present invention is mounted on an automobile, if this mounting is done with a mounting shaft or screw that acts outside the periphery of the optical block, the mounting area may include the location where the centering mechanism is located. It is preferable to select a reflector area of . Mechanisms of this type serve as a partial reinforcement of the optical block, and it is clearly most preferred to mount the optical block with a fixing device located in this strongest area.

In the present invention, a glass plate component is fitted into the front opening of a reflecting mirror component with a predetermined clearance, one of the opposing parts of the two components has a groove formed in the radial direction, and the other has a groove formed in the radial direction. It has a protrusion that slides in the groove, and the groove and the protrusion form a centering mechanism, so even if there is a difference in the degree of thermal expansion between the glass plate component and the reflector component, the glass The outer circumferential edge of the plate component does not push the front opening of the reflecting mirror component wide, and as a result, there is an effect that the front opening of the reflecting mirror component is prevented from being damaged.

In addition, since the groove and the protrusion of the present invention are made slidable, when a difference occurs in the facing area between the reflector component and the glass plate component due to thermal expansion or contraction, the reflector component and the glass plate component There is an effect that there is no possibility that the light beams will be distorted or damaged due to sliding on each other, causing distortion in the light beams.

Furthermore, in the present invention, since a plurality of grooves and protrusions are provided in the radial direction, when there is a difference in the amount of expansion/contraction between the reflective mirror component and the glass plate component due to heat, the grooves and the protrusions can be slid together. Combined with the movable structure,
The center of the glass plate component is held on the central axis of the reflecting mirror component, which has the effect of not causing distortion in the light beam.

[Brief explanation of the drawing]

FIG. 1 is a front view of an optical block assembled according to the present invention, FIG. 2 is a partial sectional view taken along the cutting line of FIG. 1, and FIG. 3 is a front glass according to the present invention. FIG. 3 is a perspective view showing how a plate and a reflecting mirror are assembled. DESCRIPTION OF SYMBOLS 10...Reflector, 11...Encircling flange part, 16...
Projection, 26...Groove, 20...Glass plate, 30...Adhesive.

Claims (1)

[Claims] 1. A plastic reflector whose front opening is surrounded by a flange, and a front glass fitted into the flange, the flange being aligned with the central axis of the reflector. It has an end surface that is substantially parallel to the intersecting opening surfaces, and a peripheral wall that surrounds the outer edge of the end surface and is approximately perpendicular to the opening surface, and the front glass is in contact with the end surface, and the peripheral wall is in contact with the end surface. a contact surface forming a predetermined gap between the reflector and the end surface, and the contact surface and the end surface are in contact so as to be able to slide relative to each other in the radial direction against thermal deformation of the reflecting mirror and the front glass. A groove is formed on one of the end surface of the flange portion and a contact surface of the front glass, and a plurality of sets of protrusions that fit into the groove are formed on the other, and the set of the groove and the protrusion is formed on the opening surface. The groove portion and the protruding portion are formed in at least two directions that intersect with each other in the interior, and the set of the groove portion and the protrusion portion is fitted so as to be able to slide relative to the reflecting mirror and the front glass in the radial direction against thermal deformation of the front glass. An optical block for a headlamp, in which the glass and the flange are fixed with an adhesive in contact with each other. 2. The front according to claim 1, wherein the protrusion has a truncated cone or a truncated pyramid shape, and the groove has a shape that fits into the protrusion of this shape. Optical block for lighting. 3. The headlight according to claim 1, wherein the groove portion or the protrusion portion is provided on two orthogonal diameters of an end surface portion of the flange portion or a contact surface portion of the front glass. Optical block for lights.