Releasing Fixture by Induction Heating

Objective A fixture used in lens grinding uses a metallic bond to secure the glass form to the fixture during grinding. Induction is used to release the lens from the bonding material
Material bonded grinding fixtures; Teflon-coated helical coil
Temperature 55°C (130ºF)
Frequency 355 kHz
Equipment 6KW induction heating system including:
• Coil: custom-designed helical coil
• Workhead: two 1.5μF capacitors (Total 0.75μF)
Process The bonded assembly is placed (glass up) within a helical coil which circles the bonding slug. Induction heats the material to the melting point in 5-7 seconds. Upon melting, the lens is released from the fixture, the fixture drops away.
Results/Benefits Efficiency: the bond is released cleanly, in a very few seconds

Economy: energy is applied only where required