DE102007020418A1 - Light guiding body manufacturing method, involves applying flowable substance in molding area for forming outer sections of light guiding body adhering to partial peripheries of core section, respectively - Google Patents

Abstract

The method involves applying a flowable substance (9) in a molding area for forming a core section of a light guiding body (1). Another flowable substance is applied in the molding area through a passage channel on one side of the core section opposite to an inlet point of the latter substance. The channel is formed between two opposite sides of the core section. The latter substance and a third flowable substance are applied in the molding area for forming outer sections of the body adhering to partial peripheries of the core section, respectively. An independent claim is also included for a device for executing a method for manufacturing a light guiding body.

Description

The The invention relates to a method for producing a light guide body from a flowable before the final solidification Material in a mold cavity of a tool, wherein at least two flowable Materials introduced into the mold offset in time become.

Further The invention relates to a device for implementation the above method and a light guide.

From the DE 101 63 117 C1 a method for producing a light guide is known, which is connected by injection molding with a light source containing electronics protection body. In a first step, a first flowable material is introduced into a mold, wherein the LED chip designed as a light source is flowed around the release of the electrical connections. In a second step, a second flowable material, which forms the light guide body, is introduced at an opposite inlet location of the molding space. The known method is used to produce a light source connected in one piece with a light guide body. Outer sides of the light guide can be subsequently provided with a coating, for example, form a galvanically mirrored outer surface.

task The present invention is a method for manufacturing a light guide body or a device for implementation specify the method or a light guide, so that in a simple and inexpensive way a high volume Light guide with high dimensional and surface quality is created.

to Solution to this problem is the invention in connection with the preamble of claim 1, characterized in that in a first step, a first flowable Material is introduced into a mold cavity to form a core section of the light guide, that in a second step second flowable material through a between two opposite sides of the core section forming passageway at least one to the inlet point of the second flowable material opposite side of the core portion is introduced into the mold space for formation one adhered to a first partial circumference of the core portion first outer portion of the light guide body and that in a third step optionally increases the shape space and that a third flowable material in the mold space is introduced to form at least a second Partial circumference of the core portion adhering second outer portion of the light guide body.

Of the particular advantage of the method according to the invention is that in a cost effective way a multi-layered Structure of a relatively thick-walled light guide created is, whereby by the application of relatively thin outer sections on the core section improved quality of the exterior surfaces the light guide is guaranteed. basic idea The invention is a light guide from a relative large-volume core portion of a first material and through a relatively thin and surrounding the core portion Outer portion of a second material and / or third Form material. The core section can through a pre-molded part be formed on the no high demands for dimensional stability have to be asked. The outer section can be formed by a material that has relatively high demands to dimensional accuracy and surface quality the optical surfaces of the light guide is sufficient. For example, at least a part of the outer portion consist of a temperature-resistant material. Thereby, that an outer portion of the light guide by a material is produced during the introduction the same in the mold space a passageway through the core portion forms, can be advantageously ensured that the flowable Materials only from a common side in the mold space can be introduced.

Advantageous The invention enables a cost-effective production a light guide with a relatively short cycle time. The light guide can be relatively thick-walled be and satisfy high standards of and surface quality.

To a development of the invention have introduced into the mold cavity flowable materials different color additives on, so that a multilayer light guide different Colors on a front, in a middle area and at one Rear side has. In this way, the light guide be formed two-tone or tri-color. Alternatively you can the flowable introduced into the mold cavity Materials also be made of different materials, so that the core section, for example, by a temperature-resistant Outside section is surrounded.

To a development of the invention can in the second production step and in the third manufacturing step, the same materials in the Form space are introduced. Only by moving a mold Thus, one can complete the core section completely homogeneous outer portion are formed. Advantageously Thus, a light guide only with the provision of two different materials and a single inlet point produce.

to Solution of the problem is the invention Lichtleitkörper characterized in that the first Outer portion of the light guide a back the same forms, which has at least partially optical elements.

Of the particular advantage of the light guide is that a core section with no special requirements for dimensional accuracy and an outer portion at least partially surrounding the core portion with very good surface quality and dimensional accuracy can be formed. Preferably, at least one outer portion the light guide partially provided with optical elements be that a predetermined refraction or scattering of the light enable the light guide.

To a development of the invention may be an outer section of the light guide form a lateral surface, the end has a fastener. This can advantageously a simplified attachment of the light guide be achieved on other optical components of a lighting unit.

To a development of the invention, the core portion in a Angular contact area on an opening through the second material and / or the third material is filled. This breakthrough is through the passageway during manufacture formed by the second flowable material from the inlet point to an opposite side flows through the core section. This opening is not visible from the outside and includes one in comparison to the core section relatively small volume range.

Further Advantages of the invention will become apparent from the other dependent claims.

One Embodiment of the invention will be described below explained in more detail in the drawings.

It demonstrate:

1 a rear view of an optical fiber body,

2 a section through a mold during a first manufacturing step,

3 a section through the mold during the second manufacturing step and

4 a section through the mold during the third manufacturing step.

A light guide body 1 has a front 2 , one of the front 2 opposite back 3 as well as one the front 2 and the back 3 connecting lateral surface 4 on. The light guide body 1 may be associated with a light source, not shown, for example, an LED (light emitting diode) or incandescent lamp, preferably at a distance from the back 3 is arranged. The light emitted by the light source is at the back 3 of the light guide body 1 coupled. For this purpose, the back side 3 Optical elements on which a prismatic structure 5 form. At a radially outer edge of the back 3 or on one of the lateral surface 4 against the light exit direction 6 oriented extension is a barb-shaped fastener 7 executed, by means of which the light guide body 1 can be attached to an adjacent component, such as a carrier.

The back 3 facing away from the front 2 has a slightly arcuate or planar contour, which is an optical surface 8th forms, at the by the light guide body 1 guided light is decoupled to the environment. The Op tikfläche 8th For example, it may be provided with prism optics to form larger deflection angles of the transmitted light.

For the production of the cup-shaped light guide body 1 becomes a first flowable material in a first manufacturing step 9 in one by two tool halves 10 . 10 ' limited mold space injected. The first flowable material 9 serves to form a relatively large-volume core portion of the light guide 1 ,

In a second manufacturing step is by moving the first mold half 10 and / or the second tool half 10 ' the mold cavity is enlarged so that at a same inlet point 11 , on which already the first flowable material 9 has been injected in the mold cavity, a second flowable material 12 is injected. The thickness (D _Z ) of the plasticized core section 9 is in the area of the intake point 11 by means of one of the tool surface 10 ' in the direction of the inlet 11 protruding tool extension 13 relatively small. The second flowable material 12 spreads on the intake point 11 opposite side to cover a first part of the circumference of the core portion 9 and forms a first outer portion of the light guide body 1 one at the back 3 and on the other hand on the lateral lateral surface 4 is arranged.

By appropriate training of the tool halves 10 respectively. 10 ' the formation of the back prism structure takes place 5 and the marginal fasteners 7 ,

In a third manufacturing step, the mold cavity is moved by moving the mold halves 10 . 10 ' further enlarged, so that a previously uncovered second partial circumference of the core section 9 by injecting a third flowable material 16 is covered. The third outer material forming a third flowable material 16 is a continuous cover, which is the later front 2 of the light guide body 1 forms. For this purpose, on the one hand, the front of the core section 9 and a front end 17 of the first outer section 12 covered. The first material 9 and the second material 12 and the third material 16 may be formed of a different transparent plastic material or of the same plastic material. For example, the materials 9 . 12 . 16 be formed in different colors.

The core section 9 of the light guide body 1 has an opening in a gate area 15 on, by the second material 12 and / or the third material 16 is filled.

How out 4 is apparent, is a thickness D _{R of} the first outer portion 12 and a thickness D _{V of} the second outer portion 16 smaller than the thickness D of the core portion 9 , The thickness D _{R of} the first outer portion 12 and / or the thickness D _{V of} the second outer portion 16 can in the range of D _{Z of} the plasticized core section 9 in the area of the intake point 11 during the injection of the first flowable material 9 be.

According to an alternative embodiment, the second material 12 and the third material 16 also consist of a same plastic material. For example, the first material 9 and / or the second material 12 and / or the third material 16 be provided with different color additives, so that a multilayer and different colors having Lichtleitkörper 1 is formed. The light guide body 1 is preferably rotationally symmetrical, wherein the inlet point 11 a central axis 18 of the light guide body 1 cuts.

According to an embodiment, not shown, in the second and third manufacturing step, a same flowable material can be introduced, so that a front and rear part of the circumference of the core portion is covered by a plastic material having the same material properties. The light guide according to the invention 1 is thus formed on the one hand by injection molding of a core portion, wherein the second material flows through for injection molding through the core portion. On the other hand, the light guide 1 produced by injection molding on the front of the core section. It is essential that the core section is completely enveloped by a subsequently introduced second and / or third material. During introduction of the second material or third material into the molding space, the previously introduced first material or second material is still in the plasticized state.

It is advantageous by the light guide according to the invention 1 the occurrence of defects in the body, namely the occurrence of sink marks or voids, avoided. With the injection molding process according to the invention, any desired geometries of light-conducting bodies can be produced. The invention enables an optimal mold filling of optical elements on the outer surface in thick-walled components.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 10163117 C1 [0003]

Claims (11)

Method for producing an optical waveguide from a material which is flowable before the final solidification into a mold space of a tool, wherein at least two flowable materials are introduced into the mold with a time offset from one another, characterized in that - in a first step a first flowable material ( 9 ) is introduced into a mold space to form a core portion of the light guide body ( 1 ), That in a second step a second flowable material ( 12 ) by a between two opposite sides of the core portion ( 9 ) forming passageway ( 14 ) to at least one to the inlet point ( 11 ) of the second flowable material ( 12 ) opposite side of the core section ( 9 ) is introduced into the mold space to form a first partial circumference of the core portion ( 9 ) adhering first outer portion of the light guide body ( 1 ) and - that, where appropriate, in a third step, the mold cavity is enlarged and that a third flowable material ( 16 ) is introduced into the mold space to form at least a second partial circumference of the core portion ( 9 ) adhering second outer portion of the light guide body ( 1 ). Method according to claim 1, characterized in that the first flowable material ( 9 ) and the second flowable material ( 12 ) and the third flowable material ( 16 ) at a common intake point ( 11 ) are injected successively into the mold space. Method according to claim 1 or 2, characterized in that the first flowable material ( 9 ) is injected into the mold space of a separate tool to form a preform. Method according to one of claims 1 to 3, characterized in that the first flowable material ( 9 ) and / or the second flowable material ( 12 ) and / or the third flowable material ( 16 ) are injected successively with different color additives and / or different plastic materials. Method according to one of claims 1 to 4, characterized in that in the second step and the third Step the same flowable material into the Mold space is introduced. Optical waveguide manufactured according to a method of claims 1 to 5, characterized in that the first outer section ( 12 ) of the light guide body ( 1 ) a back ( 3 ) thereof, which at least partially optical elements ( 5 ) having. Optical guide according to claim 6, characterized in that the first outer section ( 12 ) a lateral surface ( 4 ) of the light guide body ( 1 ), the end via a fastener ( 7 ). Optical guide according to claim 6 or 7, characterized in that the second outer portion ( 16 ) a front side ( 2 ) of the light guide body ( 1 ), which serves as a planar optical surface ( 8th ) or as an arcuate optical surface ( 8th ) is formed with prismatic optics. Optical guide according to one of claims 6 to 8, characterized in that the core section ( 9 ) of the light guide body ( 1 ) has in an Angussstellenbereich an opening through the second material ( 12 ) and / or the third material ( 16 ) is filled out. Optical guide according to one of claims 6 to 9, characterized in that the thickness (D _V , D _R ) of the first outer portion ( 12 ) and / or the second outer section ( 16 ) is smaller than the thickness (D) of the core section ( 9 ). Apparatus for carrying out the method according to one of claims 1 to 5.