Process for manufacturing a headlight lens for a motor vehicle headlight

Patent metadata

Field	Value
Publication number	US-9358706-B2
Application number	US-201214114315-A
Country	US
Kind code	B2
Filing date	Feb 3, 2012
Priority date	Apr 29, 2011
Publication date	Jun 7, 2016
Grant date	Jun 7, 2016

Abstract

A process for manufacturing a headlight lens for a vehicle headlight, wherein a blank is molded from transparent plastic material by means of an injection molding process, and wherein the blank is subsequently blank-molded by means of a final contour mold to form the headlight lens.

First claim

The invention claimed is:

1. A method for manufacturing a headlight lens for imaging a light-dark-borderline on a roadway, the method comprising:
providing an injection mold having an injection mold cavity whose thickness is no smaller than 50% of the diameter of the injection mold cavity;
providing a final contour mold;
injection molding a blank of transparent plastic material by means of said injection mold;
cooling the blank and the removing the blank from the injection mold before its mean temperature goes below the flow temperature of the plastic material; and
press-molding the blank by means of said final contour mold to form the headlight lens for imaging a light-dark-borderline on a roadway.

2. The method as claimed in claim 1 , wherein the thickness of the injection mold cavity is no larger than 70% of its diameter.

3. The method as claimed in claim 2 , wherein the injection mold includes a first injection mold component and at least a second injection mold component, wherein a portion of an injection mold cavity of the first injection mold component and a portion of an injection mold cavity of the second injection mold component form a transition with each other, which transition has a continuous first derivative without any bend or kink.

4. The method as claimed in claim 1 , wherein the injection mold cavity includes a first area for molding a first convex surface of the blank immediately after filling the injection mold and a second area opposing the first area, and for molding a second convex surface of the blank immediately after filling the injection mold, wherein the first area and the second area form a transition with each other having a continuous first derivative without any bend or kink.

5. The method as claimed in claim 1 , wherein the injection mold includes a first injection mold component and at least a second injection mold component, wherein a portion of an injection mold cavity of the first injection mold component and a portion of an injection mold cavity of the second injection mold component form a transition with each other, which transition has a continuous first derivative without any bend or kink.

6. The method as claimed in claim 1 , wherein the injection mold includes a first injection mold component and at least a second injection mold component, wherein a portion of an injection mold cavity of the first injection mold component and a portion of an injection mold cavity of the second injection mold component form a transition with each other, which transition is configured without any bend.

7. The method as claimed in claim 1 , wherein the final contour mold includes a bottom mold and a top mold, wherein the blank is placed on the bottom mold.

8. The method as claimed in claim 7 , wherein the contact face between the bottom mold and the blank is no larger than 20% of the maximum cross sectional face of the blank when viewed in parallel to the contact face between the bottom mold and the blank.

9. The method as claimed in claim 1 , wherein before the press-molding occurs, the blank is cooled down and heated again.

10. A method for manufacturing a headlight lens for imaging a light-dark-borderline on a roadway, the method comprising:
providing an injection mold forming an injection mold cavity, the injection mold including a first injection mold component and at least a second injection mold component, wherein a portion of an injection mold cavity of the first injection mold component and a portion of an injection mold cavity of the second injection mold component form a transition with each other such that the transition has a continuous first derivative without any bend or kink;
providing a final contour mold;
injection molding a blank of transparent plastic material by means of said injection mold;
cooling the blank and the taking the blank out of the injection mold after moving apart the first injection mold component and the second injection mold component; and
press-molding the blank by means of said final contour mold to form the headlight lens for imaging a light-dark-borderline on a roadway.

11. The method as claimed in claim 10 , wherein the blank is taken out of the injection mold before its mean temperature goes below the flow temperature of the plastic material.

12. The method as claimed in claim 10 , wherein the final contour mold includes a bottom mold and a top mold, wherein the blank is placed on the bottom mold.

13. The method as claimed in claim 12 , wherein the contact face between the bottom mold and the blank is no larger than 20% of the maximum cross sectional face of the blank when viewed in parallel to the contact face between the bottom mold and the blank.

14. The method as claimed in claim 10 , wherein before the press-molding occurs, the blank is cooled down and heated again.

15. A method for manufacturing a headlight lens for imaging a light-dark-borderline on a roadway, the method comprising:
providing an injection mold;
providing a final contour mold;
injection molding a blank of transparent plastic material is by means of said injection mold;
cooling the blank and then taking the blank out of the injection mold before its mean temperature goes below the flow temperature of the plastic material; and
press-molding the blank by means of said final contour mold to form the headlight lens for imaging a light-dark-borderline on a roadway.

16. The method as claimed in claim 15 , wherein the final contour mold includes a bottom mold and a top mold, wherein the blank is placed on the bottom mold.

17. The method as claimed in claim 16 , wherein the contact face between the bottom mold and the blank is no larger than 20% of the maximum cross sectional face of the blank when viewed in parallel to the contact face between the bottom mold and the blank.

18. The method as claimed in claim 15 , wherein before the press-molding occurs, the blank is cooled down and heated again.

Assignees

• Mühle Peter
• Willke Alois
• Goldammer Hagen
• Schöppner Volker
• Leister Christian
• Docter Optics Se

Inventors

• Mühle Peter
• Willke Alois
• Goldammer Hagen
• Schöppner Volker
• Leister Christian

Classifications

• F21S48/1283

  Mechanical Engineering · mapped topic

• B29C45/561

  Injection-compression moulding · CPC title

• B29D11/00317 Primary

  Production of lenses with markings or patterns · CPC title

• F21S48/1258

  Mechanical Engineering · mapped topic

• B29C45/0055 Primary

  Shaping · CPC title