Drop detection

US8376506B2 · kind B2 · utility

Assignee

• HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P. · US

Inventors

• Matthew A. Shepherd · Vancouver, US
• Alexander Govyadinov · Corvallis, US
• Erick B. Kinas · Camas, US
• Paul A. Richards · Corvallis, US
• Tom Deskins · Albany, US
• Steven H. Walker · Camas, US

Key dates

• Filing date: Jul 29, 2009
• Grant date: Feb 19, 2013
• Expiry date: Nov 25, 2030

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B41J29/393
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

Abstract

In one embodiment, a drop detection method includes: moving a light source along a first side of the drop zone to illuminate drops passing through a drop zone; and, without blocking any part of the drop zone, detecting light scattered off the drops as the drops pass through the drop zone. In another embodiment, a drop detector includes: a light source on a first side of the drop zone for illuminating drops passing through a drop zone; a light detector on the first side of the drop zone near the light source and a movable carriage carrying the light source and the light detector. The light detector is exposed to the drop zone for detecting light scattered off drops as the drops pass through the drop zone. The carriage is movable along the first side of the drop zone in a direction transverse to the drop direction.