Stirring hot plate

US7919731B2 · kind B2 · utility

Assignee

• Barnstead/Thermolyne Corporation · US

Inventors

• Curt McFadden · Dubuque, US
• Kenneth Hermsen · Dyersville, US
• Roger Earle · Dubuque, US
• James R. Edwards · Bellevue, US
• Kerry W. Leppert · Dubuque, US
• Eric Jackson · Dubuque, US
• Eric Garz · Platteville, US
• Mark D. Lockwood · Dubuque, US
• John L. Meek · Rock Hill, US

Key dates

• Filing date: Oct 30, 2007
• Grant date: Apr 5, 2011
• Expiry date: Sep 25, 2028

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01L2300/1827
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

A stirring hot plate for simultaneously heating and stirring a mixture includes a phase controlled motor that spins magnets which couple to, and thereby spin, a stir bar within the mixture. In addition to spinning the magnets, the motor includes an operational mode in which the motor is rapidly braked thereby quickly spinning down the stir bar. The stirring hot plate also includes a visual indicator to the user that the platform is hot-to-the-touch that is especially effective when the stirring hot plate is not in use.