Temperature actuated electromechanical pressure relief valve
Presented are embodiments of pressure relief valves for use in water supply systems to prevent damage thereto caused by over pressure resulting from freezing of the water therein. In one embodiment the pressure relief valve is included in an electromechanical solenoid controlled water valve particularly useful in appliances such as washing machines, water heaters, refrigerators, etc. Prior to the main valving member, a spring loaded pressure relief valving member is included. Once the pressure within the valve exceeds the spring force, which is set below the failure pressure of the water supply system and the valve, the pressure relief valving member opens to allow a flow of water therethrough. Alternatively or additionally, a temperature active device such as a bi-metal disc is interposed between the spring and the pressure relief valving member to provide actuation thereof below a predetermined temperature.
1. A pressure relief valve, comprising:
a valve housing having an inlet, an outlet, and a main water flow channel defined therebetween, the housing further defining a relief port that is fluidly coupled to the main water flow channel;
a valving member operably engaging the relief port; and
a spring having a spring force selected to be lower than a failure pressure of the valve housing, the spring being operably coupled to the valving member to hold the valving member in sealing contact with the relief port when a pressure within the valve housing is below the spring force and to release the valving member from sealing contact when the pressure within the valve housing is above the spring force; and
wherein release of the valving member from the sealing contact allows a flow of water from the main flow channel to exit the valve housing through a water flow through coupling fluidly connected to the relief port; and a solenoid controlled valve interposed between the inlet and the outlet, downstream of the relief port, to control a main flow of water through the main water flow channel from the inlet to the outlet;
wherein the valving member includes a bi-metal disc through which the spring force is applied, and wherein deflection of the bi-metal disc unseats the valving member from the relief port to allow the flow of water from the main water flow channel through the relief port when a temperature of the bi-metal disc is below a predetermined temperature.
2. The pressure relief valve of claim 1 , wherein the relief port defined by the valve housing is circular.
3. The pressure relief valve of claim 1 , wherein the water flow through coupling fluidly connected to the relief port defines an exit flow path out of the valve housing.
4. The pressure relief valve of claim of 2 , wherein a circular flange of the water flow through coupling sealingly engages an outer periphery of the relief port of the valve housing to fluidly connect the water flow through coupling to the relief port of the valve housing.
5. The pressure relief valve of claim of 3 , wherein a water flow coupling defines the water flow coupling channel that extends from the valve housing transverse to the main water flow and approximately parallel to a relief flow channel defined by the relief port.
6. The pressure relief valve of claim 5 , wherein the relief flow channel and the water flow channel extend in opposite directions radially away from the valve housing.
7. The pressure relief valve of claim 1 , wherein a solenoid of the solenoid controlled valve and the water flow through coupling are located on a same side of the valve housing.
8. The pressure relief valve of claim 1 , wherein an outermost peripheral surface at the inlet of the valve housing is threaded.
9. A pressure relief valve, comprising:
a valve housing having an inlet, an outlet, and a main water flow channel defined therebetween, the housing further defining a relief port that is fluidly coupled to the main water flow channel;
a valving member operably engaging the relief port; and
wherein a temperature sensitive actuation device of the valving member comprises a bimetallic plate and spring, the bimetallic plate and spring operable to unseat the valving member to allow a flow of water to exit the relief port out of the valve housing;
wherein a spring force of the spring is applied through the bi-metal plate to seat the valving member, and wherein deflection of the bi-metal plate unseats the valving member from the relief port to allow the flow of water from the main water flow channel through the relief port when a temperature of the bi-metal plate is below a predetermined temperature.
10. The pressure relief valve of claim 9 , wherein the spring force is selected to be lower than a failure pressure of the valve housing, the spring being operably coupled to the valving member to hold the valving member in sealing contact with the relief port when a pressure within the valve housing is below the spring force.
11. The pressure relief valve of claim 9 , wherein the bimetallic plate has a first state and a second state; and
wherein in the first state the spring biases the bimetallic plate in a first direction to sealingly engage the relief port and wherein in the second state the bimetallic plate biases the spring in a second direction, opposite the first direction, to unseat the bimetallic plate from the relief port to allow a flow of water from the main water flow channel through the relief port.
12. The pressure relief valve of claim 9 , wherein a flow path of the relief port extends transverse to the main flow path.
13. The pressure relief valve of claim 9 , wherein the relief port is in fluid connection with a water flow through coupling.
14. The pressure relief valve of claim 13 , wherein the water flow through coupling is in fluid communication with an appliance for sensing a flow through the relief port and out of the valve housing.
15. The pressure relief valve of claim 14 , wherein water flow through coupling is conical and comprises external threads.
16. The pressure relief valve of claim 9 , wherein the relief port is downstream of the inlet port and upstream of a solenoid controlled valve, the solenoid controlled valve controlling the main flow of water through the main water flow channel from the inlet to the outlet.