1. Field of the Invention
The present invention relates to valves. More specifically, the present invention relates to a temperature actuated valve that automatically opens in response to freezing temperatures, thereby enabling flow to continue through the valve, and that automatically closes when the temperature rises above freezing.
2. Background Information
Damage often occurs to water pipes and faucets that are externally exposed to freezing conditions due to the expansion of water when it freezes. The most common solution is to crack the faucet open sufficiently enough to allow a slow dripping of the water. This flowing of water is typically warm enough to prevent freezing of the piping upstream of the faucet. The warmer water usually comes from buried pipes at a temperature above freezing at a rate faster than it can be frozen. However, faucet dripping is not always feasible, as no one may be available to open the faucet, the faucet may be forgotten, or the cold weather may be unexpected. Further, this dripping can be wasteful of water in that the faucets often drip longer than is necessary.
As a solution to this concern of frozen pipes and faucets, a multitude of alternatives have been proposed that automatically allow the faucet to drip when freezing conditions are encountered. Typically, these alternatives include a thermally active element utilized in opening and closing various types of valves. Examples of thermally active elements include a combination of materials having differing coefficients of thermal expansion arranged such that one moves in relation to another with a change in temperature, a liquid that condenses at a specific temperature, or a wax that changes phases at a known temperature with a corresponding change in volume. Valves containing such thermal elements are constructed so that movement of the thermal elements enables movement of a plug, thereby opening the faucet and allowing water to drip.
However, many times a hose or other accessory may be attached to the end of the faucet. This accessory may already contain fluid in it that has frozen, causing the outlet of the faucet to be blocked. Accordingly, there is a need for a valve having a secondary means of permitting flow there through in the event that the primary means is prevented from allowing flow there through.
The present invention disclosed herein alleviates the drawbacks described above with respect to responding to fluid flow through a valve, particularly in that instance wherein the primary means of permitting fluid flow there through is unable to do so. The valve of the present invention is easily installed in a common water faucet. It allows the control of the flow of the volume of liquid to be unattended, regardless of how low the surrounding air temperature may be. The valve further allows such unattended control, even should the primary means of release, e.g., the outlet of the faucet, be blocked preventing flow there through.
The valve of the present invention is temperature and pressure sensitive and has a valve piston for regulating flow through the valve The valve further has a valve piston guide for directing movement of said piston, with the piston guide having one or more passages there through, a thermal element for enabling movement of the piston, and an elongated housing having an anterior and posterior end and an interior wall able to house the piston, guide and thermal element. The housing also has of two or more passages able to aid the piston in regulating flow, with at least one of the passages placed towards the anterior end of the housing, and at least one of the passages placed towards said posterior end of the housing.
The present invention further provides a method of controlling flow through a faucet in freezing conditions. The faucet has a valve in communication with the faucet, with the valve having a valve housing with an anterior end and a posterior end and an internal wall. The housing houses a valve piston, piston guide, piston seat and thermal element. The thermal element is able to expand and contract according to the surrounding air temperature, and the piston is sealably engaged with the seat. The method comprising the steps of contracting the thermal element as the surrounding air temperature approaches the freezing temperature of water; moving the valve piston towards the anterior end of the housing; and breaking the piston""s sealable engagement with the seat, thereby automatically creating a flow passage through the valve. The flow passage through the valve automatically closes as the surrounding air temperature rises above a predetermined temperature.
As designed, the valve of the present invention is easily and conveniently installed in a faucet. Its simple design allows it to be inexpensively manufactured. It may be manufactured in a wide range of sizes, based upon the size of the flow line to be served. By proper selection of materials, the present invention may be used for controlling a wide variety of flow.
The valve of the present invention is comprised of at least two components that enable it to overcome those limitations that are encountered with typical temperature activated valves. These components include a valve piston and one or more valve piston seats that interact with one another to allow or prevent flow through the valve. Each seat communicates with one or more ports for allowing flow there through. The ports are closed when the piston is in contact with the seat, and opened when the piston is disengaged with the seat.
As disclosed herein, the valve is further comprised of a thermal element able to expand and contract based upon variations in temperature. As the element expands and contracts, the piston is moved so that it sequentially engages and disengages with the seat(s), thereby closing and opening the valve seat ports.
Additional ports are positioned on the valve such that flow may automatically continue through the faucet. These additional ports are found in differing locations on the valve. One is positioned so that flow may occur through the valve and faucet in the event of freezing temperatures. In the event that flow through the outlet of the faucet is blocked, e.g., a hose is attached to the outlet blocking flow, or fluid at the outlet is frozen blocking flow, another secondary port is positioned on the valve so that flow can bypass the faucet outlet, avoiding damage due to frozen pipes and/or faucets. By opening these ports, flow through the valve is permitted regardless of surrounding air temperature.
In the manner of the present invention, flow through the first port and out the faucet occurs due to freezing conditions. The secondary port is opened by both temperature and pressure due to the faucet outlet being blocked. The pressure for opening the secondary port may be predetermined by changing the diameter of the piston.
The general beneficial effects described above apply generally to each of the exemplary descriptions and characterizations of the devices and mechanisms disclosed herein. The specific structures through which these benefits are delivered will be described in detail herein below.