Electromechanical Temperature Regulation System for Providing Tempered Mix Water
AssigneePVI Industries, Inc.
InventorMark A. Ferguson
Life of this patent
Estimating the term…
Abstract
A thermostatic mixing valve is used in a tempered water blending system. A cold water bypass line in the system acts under the control of a modulating valve and electronic controller to divert cold water back to a temperature sensing element in the mixing valve. By flooding the temperature sensing element, the mixing valve detects a false temperature and adjusts its flow rate of hot and cold water accordingly. The electronic controller acts in reverse of normal fashion, providing negative feedback to the sensing element of the mixing valve.
Claims13
A system for supplying tempered water, the system comprising:
- a cold water inlet conduit;
- a hot water inlet conduit;
- a thermostatic mixing valve operatively connected to said cold and hot water inlet conduits for mixing water from the cold and hot water inlet conduits into a single tempered water output stream having a desired set point temperature, the thermostatic mixing valve having a temperature sensing element for controlling the mixing valve position to maintain the desired set point temperature in the tempered water output stream;
- a tempered water outlet conduit for receiving the tempered water stream, the tempered water outlet conduit having a temperature sensing element located therein;
- a cold water bypass line for diverting cold water from the cold water inlet conduit upstream of the thermostatic mixing valve and for supplying cold water back to the temperature sensing element of the thermostatic mixing valve to flood the temperature sensing element;
- a modulating valve located in the cold water bypass line for controlling the flow of water in the cold water bypass line;
- an electronic controller operatively associated with the modulating valve and responsive to changes in temperature sensed by the temperature sensing element located in the tempered water outlet conduit for controlling the flow of cold water back to the sensing element of the thermostatic mixing valve.
A system for supplying tempered potable water from a hot water source supplied by a heat exchanger, the system comprising:
- a cold water inlet conduit;
- a hot water inlet conduit;
- a mechanically operated, three-way, thermostatic mixing valve operatively connected to said cold and hot water inlet conduits for mixing water from the cold and hot water inlet conduits into a single tempered water output stream having a desired preset temperature, the thermostatic mixing valve having a temperature sensing element for controlling the mixing valve position to maintain the desired preset temperature in the tempered water output stream, the sensing element acting on a sleeve in the valve interior to open or close the valve;
- a tempered water outlet conduit for receiving the tempered water stream, the tempered water outlet conduit having a temperature sensing element located therein downstream of the thermostatic mixing valve;
- a cold water bypass line for diverting cold water from the cold water inlet conduit upstream of the thermostatic mixing valve and for supplying cold water back to the temperature sensing element of the thermostatic mixing valve to flood the temperature sensing element;
- a modulating valve located in the cold water bypass line for controlling the flow of water in the cold water bypass line;
- an proportional integral derivative electronic controller operatively associated with the modulating valve and responsive to changes in temperature sensed by the temperature sensing element located in the tempered water outlet conduit for controlling the flow of cold water back to the sensing element of the thermostatic mixing valve;
- and
- wherein the flow of cold water supplied to the temperature sensing element of the thermostatic mixing valve acts to falsely shift the position of the mixing valve sleeve from a normal operating position.
Dependencies are inferred from the claim text.