Probe system for measuring the condition of materials

US4757252A · kind A · utility

Assignee

• Drexelbrook Controls, Inc. · US

Inventors

• Frederick L. Maltby · Abington, US
• Edward R. Woerner · North Wales, US
• Thomas E. Meacham, Jr. · Perkasie, US
• Steven Petersen · Grand Rapids, US

Key dates

• Filing date: Oct 25, 1985
• Grant date: Jul 12, 1988
• Expiry date: Oct 25, 2005

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N27/226
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A probe comprises a plurality of longitudinally extended conductors forming a probe electrode, a laterally displaced ground electrode and two laterally displaced active guard electrodes interposed between the probe electrode and the ground electrode. The conductors are surrounded by solid insulation and the probe guard electrodes are driven at substantially the same potential as the probe electrode. The probe is utilized to measure the condition of materials in which the probe is immersed.