Expansion element and a valve unit usable therefor

US6430950B1 · kind B1 · utility

Assignees

• Behr GmbH & Co. · DE
• Luk Fahrzeug-Hydraulik GmbH & Co. KG · DE

Inventors

• Ing. Bernd Dienhart · Cologne, DE
• Hans-Joachim Krauss · Stuttgart, DE
• Hagen Mittelstrass · Nagold, DE
• Karl-Heinz Staffa · Stuttgart, DE
• Christoph Walter · Stuttgart, DE
• Jan Hinrichs · Friedrichsdorf, DE
• Volker Seipel · Bensheim, DE
• Nguyen van Doan · Frankfurt, DE

Key dates

• Filing date: Nov 12, 1999
• Grant date: Aug 13, 2002
• Expiry date: Nov 12, 2019

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F25B2500/15
• WIPO field: Thermal processes and apparatus
• WIPO sector: Mechanical engineering

Abstract

An expansion element for a CO2 motor vehicle air conditioner includes a valve unit which can be used particularly for such an expansion element and which has a fixed throttle between an upstream valve high-pressure side and a downstream valve low-pressure side. The expansion element contains a control valve which is acted upon by the low-pressure-side refrigerant pressure or a physical quantity connected therewith as the correcting variable, or valve unit. The valve unit contains a fixed throttle and at least one additional valve component in the form of a pressure control valve which is arranged in a bypass line bypassing the fixed throttle, or in the form of a control vale influencing the passage cross-section of the fixed throttle.