Blocking piece and method for vacuum blocking a lens blank

US12059768B2 · kind B2 · utility

Assignees

• Carl Zeiss Vision International GmbH · DE
• OPTOTECH OPTIKMASCHINEN GMBH · DE

Inventors

• Gerd Nowak · Schwarzenbek, DE
• Wito Hartmann · Aalen, DE
• Roland Mandler · Heuchelheim, DE
• Oswin Lack · Weidenhausen, DE

Key dates

• Filing date: Oct 26, 2022
• Grant date: Aug 13, 2024
• Expiry date: Oct 26, 2042

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B24B13/0055
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

A blocking piece for vacuum blocking a lens blank is disclosed. The blocking piece includes a blank contacting element formed of a rigid fluid-permeable material having an upper surface for contacting the lens blank. The blocking piece further includes a support element having an upper part tightly enclosing the blank contacting element on a peripheral surface of the blank contacting element and a lower part adapted to engage with a clamping device for clamping the blocking piece. The lens blank is fixed to the upper surface of the blank contacting element by applying a vacuum within the blocking piece to provide suction through essentially the entire upper surface of the blank contacting element. The disclosure further relates to a method for blocking a lens blank and a use of an element formed of a rigid fluid-permeable material as a part of a blocking piece.