Thermostatic mixing value

US6820816B1 · kind B1 · utility

Assignee

• Horne Engineering Limited · GB

Inventor

• William P. Reid · Elderslie, GB

Key dates

• Filing date: Oct 1, 2003
• Grant date: Nov 23, 2004
• Expiry date: Oct 1, 2023

Classification

• Technology area (CPC G): Physics
• CPC primary: G05D23/136
• WIPO field: Control
• WIPO sector: Instruments

Abstract

A thermostatic mixing valve (TMV) for operation across a range of flow rates wherein during low pressure operation water enters the TVM (100) into chamber (157) around the circumference of the valve member (150) and cold valve seat (140) and hot water enters into chamber (158), the hot and cold water entering chamber (235) and becoming thoroughly mixed. At low pressure drops, the check valves (230) remain closed so the only pathway the mixed water can follow is through the sensing chamber (125) and the mixed water enters discharge portion (120) to the mixed water outlet (245), the flow path of the hot and cold water shown by pathways (255) and (260), the water becomes thoroughly mixed before entering the sensing chamber (225). For high flow rate operation the water enters and is mixed within the valve as before but in this case the pressure drop across the check valve operates the check valves (230), allowing the mixed water to follow an additional route to the discharge portion (120) and thence to the outlet (245) with additional flow pathway (265) through the valves (230), ensuring accurate temperature sensing.