Methods and apparatus for controlling flow of material past a flap valve

US5868376A · kind A · utility

Assignee

• GEI Consultants, Inc. · DE

Inventors

• Martin Koch · Neuenbürg, DE
• Günter Untch · Badenweiler, DE

Key dates

• Filing date: Oct 20, 1997
• Grant date: Feb 9, 1999
• Expiry date: Oct 20, 2017

Classification

• Technology area (CPC G): Physics
• CPC primary: G01F23/20
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A proportioning mechanism for controlling a gravitational discharge of flowable material through a passage formed of a sealing material. The mechanism includes a rotatable flap valve mounted in the passage for movement in a first range of movement while in contact with the sealing material, and a second range of movement while out of contact with the sealing material. In the second range, a free flow of material is established. The free flow is terminated when only a small amount of material is yet to be discharged in order to achieve the desired discharge weight. At that time, the flap valve is rotated to a position in contact with a flexible portion of the sealing material. Fluid pressure in a cavity situated adjacent that flexible portion is varied to oscillate the flexible portion into and out of contact with the flap valve. When the flexible portion is out of contact with the flap valve, a gap is formed which admits passage of a small amount of material.