Patent ID: 8733666

Claim:
A thermostatic mixing valve, comprising: a valve body defining a cold fluid inlet, a hot fluid inlet, a mixing chamber disposed within the valve body, and a mixed fluid outlet in fluid communication with the mixing chamber; a fluid flow regulator configured to regulate the relative flow of cold and hot fluid injected into the mixing chamber, and thus the temperature of the fluid in the mixing chamber, wherein the fluid flow regulator includes a temperature adjustment shaft that, when rotated, adjusts a temperature set-point of the fluid flow regulator; a temperature adjustment mechanism for rotating the temperature adjustment shaft of the fluid flow regulator, and thus the set-point of the fluid flow regulator, the temperature adjustment mechanism having a non-temperature adjusting position and a temperature adjusting position; the temperature adjustment mechanism including: a hand wheel having a center support, the center support forming a hole for receiving an end of the temperature adjustment shaft of the fluid flow regulator in both the non-temperature adjusting position and the temperature adjusting position, an internal surface of the center support define two or more engagement features; the temperature adjustment shaft having an outer surface that defines two or more engagement features that, when the temperature adjustment mechanism is in the temperature adjusting position, engage at least some of the two or more engagement features of the center support of the hand wheel, the two or more engagement features on the outer surface of the temperature adjustment shaft terminating before the end of the temperature adjustment shaft leaving a engagement feature free region extending between the end of the temperature adjustment mechanism and the two or more engagement features on the outer surface of the temperature adjustment shaft; and a bias mechanism biasing the hand wheel away from the temperature adjustment shaft of the fluid flow regulator, wherein the hand wheel is movable against the bias of the bias member in the temperature adjusting position to move the two or more engagement features on the inner surface of the center support to come into engagement with at least some of the two or more engagement features on the outer surface of the temperature adjustment shaft, such that rotation of the hand wheel rotates the temperature adjustment shaft of the fluid flow regulator and adjusts the set-point of the fluid flow regulator.