Improvements in or relating to thermostatic mixing valves

摘要

A thermostatic mixing vale for hot and cold water has a valve member 13 axially movable between opposed hot and cold seats to vary the relative proportions of hot and cold water admitted to a mixing chamber according to user selection of a desired water temperature and a thermostat 25 responsive to the mixed water temperature to adjust the position of the valve member 13 to maintain constant the selected water temperature. The valve member 13 is biased by a return spring in the form of a wave spring 42 having a plurality of turns 44 with transverse waves 46a configured such that adjacent turns 44 sit peak to peak. The wave spring 42 is strong in compression and weak in torsion allowing the ends of the spring 42 to move laterally to accommodate any misalignment in the components of the valve.