Sensor

Finished component in a single step

Three into one: a magnetic disc, carrier plate and protective cap are moulded into a functional rotary encoder using the three-component process. The innovative mold concept and the complex automation solution dispense with joining techniques and downstream assembly.

All operations are combined in a single process – including insertion of the sensor and overmolding with a carrier plate as well as magnetisation and assembly injection molding directly in the mold. A fully automated production cell built around a hydraulic ALLROUNDER 370 S injection molding machine featuring three (size 30, 70 and 30) injection units.

Highlights

  • From production of the individual parts to final assembly in one process
  • Injection units integrated in SELOGICA machine control system
  • Magnetization and assembly injection molding in the mold
  • Fully automated three-component production cell

Basic specifications

Rotary encoder
Cavities: 3
Part weight: 1.5 + 1.0 + 0.5 (g)
Material: PA + PBT + MABS
Cycle time: 30 s

Technology

Machine
A hydraulic three-component ALLROUNDER 370 S machine with a clamping force of 77 tons and size 0.5, 1.4 and 0.5 oz injection units is used. All three injection units are integrated in the SELOGICA control system
to the hydraulic machines

Robotic system
The highly-flexible MULTILIFT V robotic system in a longitudinal design enables vertical removal, even with the injection unit arranged in the parting line. It also performs insertion of the sensor, transfer of the magnetic disc in the mold and final assembly.
to the robotic system

Process

Encapsulating inserts
The robotic system positions the sensitive sensor on the nozzle side of the mold and the magnetic disc on the ejector side. In order to combine the insert with the magnet, the sensor is encapsulated with a carrier plate.
to the process

 Assembly injection molding
The magnetic disc made from a ferrite-containing PA is rotably mounted onto the spindle of the PBT carrier plate. This is not possible using conventional means. Joining technology and downstream operations are dispensed with, rendering the process cost-effective.

Industry

Electronics
The rotary encoders with magnetized plastic and encapsulated sensor produced using assembly injection molding are functionalized components for electronic applications. The finished molded part detects directional changes and is suitable for vehicle navigation systems, for example.
to the industry

Partners

Component concept:LTK Erlangen
Mold:Oechsler
Hot runners:Günther Heißkanaltechnik
Automation:Kiki, Xenon