Fail-safe proportional mixing valve
AssigneeMagarl, LLC
InventorsRobert Eveleigh, Kevin Kline
Life of this patent
Estimating the term…
Abstract
A fail-safe proportional mixing valve is provided that tempers a hot fluid supply by proportional flow from a hot fluid inlet and a cold fluid inlet. The valve includes a fail-safe mechanism disposed within the body of the valve to isolate flow from the hot fluid inlet in the event the temperature of the mixed fluid exceeds a predetermined set point. The valve also includes a check valve in the fluid inlets to prevent backflow in case of failure of a fluid supply. In a further aspect, the cold fluid inlet includes an adjustment set screw to adjust the cold fluid flow into the mixing valve, thereby adjusting the maximum mixed fluid temperature that can be discharged from the valve assembly.
Claims20
A fail-safe mixing valve assembly, comprising:
- a valve body defining a longitudinal axis;
- a cold fluid inlet for receiving a first flow of fluid;
- a hot fluid inlet for receiving a second flow of fluid and aligned with the longitudinal axis;
- a mixing chamber within the valve body and in variable fluid communication with the cold fluid inlet and the hot fluid inlet;
- a fluid outlet in fluid communication with the mixing chamber for discharge of fluid therefrom;
- a plug disposed within the valve body;
- a first spring operably connected to the plug for biasing the plug toward a first position wherein fluid is allowed to flow through the hot fluid inlet into the mixing chamber, the first spring concentrically disposed about at least a portion of the plug when the plug is in the first position;
- a second spring operably connected to the plug for biasing the plug toward a second position wherein fluid is allowed to flow through the hot fluid inlet into the mixing chamber;
- and
- a thermostatic member operable to cause compressive force to be applied to both the first spring and the second spring to move the plug along the longitudinal axis in a direction from the first position toward the second position in response to the temperature of fluid within the mixing chamber thereby reducing the flow rate of fluid through the hot fluid inlet.
A fail-safe mixing valve assembly, comprising:
- a valve body having a longitudinal axis;
- a cold fluid inlet for receiving a first flow of fluid;
- a hot fluid inlet for receiving a second flow of fluid and aligned with the longitudinal axis;
- a mixing chamber within the valve body and in variable fluid communication with the cold fluid inlet and the hot fluid inlet;
- a fluid outlet in fluid communication with the mixing chamber for discharge of fluid therefrom;
- a plug disposed within the valve body and axially aligned with the hot fluid inlet;
- a first spring operationally connected to the plug and axially aligned with the hot fluid inlet for biasing the plug toward a first position wherein fluid is allowed to flow through the hot fluid inlet into the mixing chamber;
- a second spring axially aligned with the first spring and the hot water inlet for biasing the plug toward a second position wherein fluid is allowed to flow through the hot fluid inlet into the mixing chamber;
- and
- a thermostatic member for controlling the position of the plug along the longitudinal axis between the first position and the second position in response to the temperature of fluid within the mixing chamber thereby modifying the flow rate of fluid through the hot fluid inlet.
Dependencies are inferred from the claim text.