Coding element with integrated limit switch

US7400269B2 · kind B2 · utility

Assignee

• Avago Technologies ECBU IP Pte. Ltd. · SG

Inventors

• Weng Fei Wong · Bukit Mertajam, MY
• Chee Foo Lum · Bukit Mertajam, MY

Key dates

• Filing date: Nov 9, 2006
• Grant date: Jul 15, 2008
• Expiry date: Nov 9, 2026

Classification

• Technology area (CPC H): Electricity
• CPC primary: H03K5/082
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An optical encoder. The optical encoder includes a coding element, an emitter, and a detector. The coding element has a track with a track pattern. The track pattern includes a plurality of optically distinguishable sections. The plurality of optically distinguishable sections includes a limit switch section. The emitter generates a light signal incident on the track of the coding element. The detector includes a limit switch photodetector positioned to detect the light signal from the emitter. The detector generates a limit switch output signal in response to the detected light signal above a limit switch threshold at the limit switch photodetector. Embodiments of this type of optical encoder implement limit switches into a single track on the coding element.