Illuminating Experience Optical LSR Fibres Ensure Pinpoint Brightness

Illuminating Experience Optical LSR Fibres Ensure Pinpoint Brightness



เครื่องฉีด ALLROUNDER 52OA ของบริษัท ARBURG ซึ่งถือได้ว่ามีความแม่นยำสูง ที่บริษัท Wihelm Weber





How can technology be used to illuminate a specific lane on the road? Car headlights that combine LED and laser technology. Light conductors paly a crucial role in focusing and conducting the light from 40 light-emitting diodes. These precision parts made of liquid silicone (LSR) are produced by Wihelm Weber from Esslingen, Germany, for its customer Hella. They are used in cars such as the Audi A8.




หลอดไฟ LED หน้ารถที่ผสมผสานการนำเทคโนโลยีซิลิโคนเหลวมาประยุกต์ใช้ในปัจจุบัน เพื่อเพิ่มความสว่างและการกระจายแสงให้ตรงตามความต้องการของผู้บริโภค (photo Continental)


Anotonio Trinchese, Head of Business Development & Sales at Weber, describes the function of the LSR serial part as follows “the matrix LED high beam has 40 small, individually adjustable light emitting diodes per unit, which project the light in two lines” The silicone light conductor collects the light from the individual LED light sources and directs it through the coupling lens system. This allows an increased flow of light to be generated from the overall system, resulting in greater light output or more defined light distribution.






The upper and lower sides of the individual silicone fingers must be produced with extreme precisions so that they deflect the light beams in a directed and glare-free manner”, explains Antonio Trinchese.


ตัวนำแสงที่ทำจากซิลิโคนเหลวถูกผลิตขึ้นจำนวนกว่า 150,000 ชิ้นต่อปีเพื่อนำไปใช้กับรถยนต์ยี่ห้อ Audi รุ่น A8 (photo ARBURG)





For Weber, this meant producing a mould with the highest surface quality and implementing a complex manufacturing cell. Due to the exacting quality standards, precise adherence to tolerances and reliable output are required. With this in mind, the company opted for a fully electric high-end machine from the ALLDRIVE series. The LSR mould has two cavities and two parting lines with a maintenance-optimised cold runner.






ALLDRIVE meets all requirement






Ulrich Bech, Head of Plastics Technology & SCM at Weber, talks about injection moulding: “Series production is done on an ALLROUNDER 520 A, which combines the maximum positioning accuracy of the electric clamping unit with a high-precision injection unit. The screw features a special geometry for LSR processing; the shot weight is 48 grams.






Because of the requirements of light transmission, the cycle times were optimised for the “cross-linking time of the LSR” and the “surface quality of the light conductor”. The machine processes a two-component LSR with a Shore hardness of 72A, which is ideal for the production of optical parts due to its high light transmission and good demouldability






Mould with Two Parting Lines





After the mould has been closed, a vacuum is applied to prevent air becoming trapped in the part. The two-component LSR is then injected and cross-links in the cavity. The first parting line opens. The part and runner are removed by a gripper, after which the second parting line opens. In this position, the overflow channel is removed, the mould closes and the process starts again.




แม่พิมพ์คุณภาพสูงแบบสองช่องสำหรับงานฉีดซิลิโคนเหลว ที่ทางบริษัท Wihelm Weber เลือกใช้ (photo Weber)



The “Move ejector to intermediate stop” function for mould breathing can be easily programmed and integrated into the production sequence with the SELOGICA control system. Raimund Jahn, Project Manager at Weber, comments on the demanding demoulding process: ” The functional geometry of the undercut light conductors requires forced demoulding, and the LSR component must not be damaged during this process.”





Traceable via DMC





The following processes take place in the production cell after the injection moulding process: A DMC (data matrix code) is lasered onto the part. The production data acquisition (PDA) system can be used to determine precisely when the individual parts were produced and suing which process parameters, down to the individual cavity. This is followed by an optical check using a camera system, and the good parts are placed in tempering trays. Removal of the moulded parts, sprue and overflow is carried out by a six-axis robot with vacuum gripper and a sprue picker.




Weber uses this automated LSR production cell to produce around 150,000 light conductors per year for the Audi A8 series

Post a Comment