Abstract:
A safety valve is provided for an appliance having an electrically operated water inlet valve for receiving water used during operation of the appliance. A valve body is connected to the water supply upstream of the inlet valve, the valve body having a flow path for allowing water to flow through the valve body to the inlet valve. An electrically operated solenoid is connected to a valve gate, the valve gate being movably carried within the valve body and movable between a closed position and an open position that allows water to flow through the flow path. A portion of an electrical current from an appliance control system to the inlet valve for opening the inlet valve is conducted to the solenoid for moving the gate to the open position. The gate is spring biased to the closed position for returning the gate to the closed position when the current ceases to flow.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to electrically operated fluid valves and relates specifically to valves used to control the flow of water to a washing machine or other appliance. 
     2. Description of the Related Art 
     Many modern appliances, such as washing machines, icemakers, and dishwashers, require a source of pressurized water for providing the appliance with water during its operation. Typically, the water is provided through a flexible hose connecting an inlet valve on the appliance to a water line, which is usually located in a wall near the appliance. In a washing machine, for example, the flexible hose limits the transfer of vibrations of the washer to the water line and allows for the washer to be moved short distances without disconnecting the hose from the water line. A manually operated valve is usually installed between a water hose and a water line, and a user can close the valve to prevent water from flowing through the hose when the hose is disconnected from the valve or the inlet of the appliance. 
     Each appliance typically has a control system that operates the inlet valves. In a washing machine, a user-operated timer mounted on the washing machine controls the cycling of the machine through the various functions in the washing process, the timer also opening the inlet valves when water is required in the machine. To allow for the washing machine to remain in a ready-to-use condition, the manual valve on each water line is usually left in the open position, water pressure remaining present in each water hose. This is also true for other appliances, providing the convenience of a ready-to-use appliance. The disadvantage to this is that a rupture of a water hose will allow water to escape, and, if undetected for an extended time, significant damage can result to the surrounding structure housing the appliance. 
     Several patents have been issued for devices used to address this problem. U.S. Pat. No. 5,918,617 to Garth discloses a system comprising a controller that controls electrically operated valves located at the water source. The controller opens and closes the valves in response to signals from the control system of an appliance, input from a moisture sensor located near the appliance, and the condition of a timer. Likewise, U.S. Pat. No. 5,934,302 to Nemelka discloses a microcontroller that senses current flow to an appliance, indicating that the appliance is in use, and opens water valves when current is flowing, the valves being installed upstream of the washing machine. The device also has pressure sensors for detecting an abnormal drop in the pressure in the water supply line. A similar device is disclosed in U.S. Pat. No. 6,003,536 to Polverari, et al., which has a controller for signaling valves to open when the controller detects the current draw of an appliance. 
     A leakage-detection system is disclosed in U.S. Pat. No. 5,992,218 to Tryba, et al., in which leak detectors are positioned near and/or in the appliance. The detectors are connected to a control apparatus that controls valves connected to the water supply. If a leak is detected, the control apparatus signals the valves to close, stopping the flow of water. 
     There is a need for an apparatus for preventing unwanted water flow through hoses connecting an appliance to a pressurized water supply that eliminates the need for a separate controller and power supply, the apparatus being electrically connected to the wiring of the appliance for relying only on the power to the inlet valve and the inlet valve control system of the appliance. 
     BRIEF SUMMARY OF THE INVENTION 
     A safety valve is provided for an appliance using water from a pressurized water supply during operation of the appliance. The appliance has an electrically operated inlet valve connected to the water supply, the inlet valve being operated by a controller of the appliance. The safety valve has a valve body connected to the water supply upstream of the inlet valve, the valve body having a flow path for allowing water to flow through the valve body from the water supply to the inlet valve. The safety valve has an electrically operated solenoid and a valve gate connected to the solenoid. The valve gate is movably carried within the valve body, the gate being movable between a closed position that prevents water from flowing through the flow path and an open position that allows water to flow through the flow path. The solenoid is connected to the appliance, such that an electrical current from the control system to the inlet valve for opening the inlet valve is conducted to the solenoid for moving the gate to the open position. The gate is spring biased to the closed position for returning the gate to the closed position when the current ceases to flow. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself however, as well as a preferred mode of use, further objects and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings. 
     FIG. 1 is a schematic view of a control system and wiring for a washing machine, the washing machine being connected to safety valves constructed in accordance with the present invention. 
     FIG. 2 is a rear view of an inlet valve assembly connected to the safety valves of FIG.  1 . 
     FIG. 3 is a side view of a safety valve of FIG. 1 installed at a water outlet. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 is a schematic diagram of elements in a control circuit  11  for a washing machine. Circuit  11  has a timer  13  for controlling motor  15 , brake  17 , and solenoids  19 ,  21  for water inlet valves (not shown). Electrical power is provided to circuit  11  through service cord  23 . 
     Timer  13  is manipulated by a user to control the operation of the washing machine. A timer knob  25  is located on an outer surface of a control panel (not shown) that houses timer  13 , timer knob  25  being pulled outward to activate timer  13  and pushed in to deactivate timer  13 . Sets of switches, such as switch set  27 , control the functioning of attached components. For example, switch set  27  controls motor  15 , with speed selector switch  29  being connected between switch set  27  and motor  15 . Water level switch  31  is connected to timer  13  for switching solenoids  19 ,  21  off and closing the inlet valves when water has reached a desired level within the washing machine. A door switch  33  controls brake  17  for stopping a spinning drum if a user opens the access door. Water selector switch  35  controls the opening of water solenoids  19 ,  21  for allowing hot or cold water (or both) to flow into the washing machine. A timer motor  37  turns knob  25  to cycle the washing machine through the various operations of a wash cycle. 
     Hot water is supplied to the washing machine under pressure through conduit  39 , and cold water is supplied under pressure through conduit  41 . Conduits  39 ,  41  are connected to ports (not shown) on the washing machine, and solenoids  19 ,  21  operate the inlet valves to control the flow of water through the ports. Timer  13  is connected to solenoids  19 ,  21  through wires  43 ,  45 , respectively, for providing an electric current to cause solenoids  19 ,  21  to open the inlet valves, allowing water to flow into the washing machine through one or both valves. When the current ceases, solenoids  19 ,  21  close the inlet valves, preventing additional water from flowing into the washing machine. 
     To prevent unwanted flow of water through conduits  39 ,  41 , for example, if one of conduits  39 ,  41  has ruptured, valves  47 ,  49  are installed in conduits  39 ,  41 , respectively. Each valve  47 ,  49  preferably contains a solenoid that is spring-biased toward the closed position, valve  47  being shown in detail in FIG.  3  and further described below. Valves  47 ,  49  are moved to an open position, allowing water to flow through conduits  39 ,  41 , only when timer  13  routes an electric current to water solenoids  19 ,  21 . 
     To provide an electric current for operating valve  47 , wire  51  is connected to wire  45  at node  53 , and wire  55  is connected to common node  57 . Wire  59  connects valve  49  to wire  43  at node  61 , and wire  63  connects to common node  57 . Optional timers  65 ,  67  may be connected between nodes  53 ,  57 ,  61  and valves  47 ,  49  for slightly delaying the opening of valves  47 ,  49  or limiting the amount of time that electrical current is supplied to keep valves  47 ,  49  open. 
     FIG. 2 is a rear view of a valve assembly  69  containing solenoids  19 ,  21 , valve assembly  69  being mounted to the washing machine. A hot-water hose (not shown) connects hot inlet  71  to an outlet of valve  47  for providing hot water, and a cold-water hose (not shown) connects cold inlet  73  to an outlet of valve  49  for providing cold water. As described above, solenoids  19 ,  21  are connected to timer  13  (FIG. 1) for controlling the release of water into the machine, and each valve  47 ,  49  is wired to open simultaneously with the corresponding valves in valve assembly  69 . As each solenoid  19 ,  21  is energized, a valve (not shown) connected to the solenoid  19 ,  21  and within assembly  69  opens to allow water in the corresponding water hose to flow through inlet  71 ,  73  and into the washing machine. 
     FIG. 2 shows the preferred method for wiring valves  47 ,  49  to the wiring for solenoids  19 ,  21 . Whereas the schematic view of FIG. 1 shows wires  55 ,  63  connected to node  57 , wires  55 ,  63  will typically be connected to separate wires, such as wires  75 ,  77 , which are paired with wires  43 ,  45 , respectively, for conducting electricity through solenoids  19 ,  21 . For valve  47 , wire  51  is connected to wire  45  with connector  79 , and wire  55  is connected to wire  77  with connector  81 . For valve  49 , wire  59  is connected to wire  43  with connector  83 , and wire  63  is connected to wire  75  with connector  85 . As timer  13  (FIG. 1) actuates one or both solenoids  19 ,  21  with an electrical current in pairs of wires  43 ,  75  and  45 ,  77 , a portion of the current passes through wires  51 ,  55  to open valve  47 , releasing hot water to flow to inlet  71 , and/or through wires  59 ,  63  to open valve  49 , releasing cold water to flow to inlet  73 . Since one or both solenoids  19 ,  21  are also energized, water flows through valve assembly  69  into the washing machine. 
     FIG. 3 is a side view of installed valve  47 , valve  49  being identical in construction and operation to valve  47 . A water pipe  87  is a portion of the pressurized water system in a structure, pipe  87  typically being located in a wall. Pipe  87  terminates in a threaded end  89  onto which is secured a manual shutoff valve  91 . Shutoff valve  91  has a valve section  93  that is parallel to the axis of pipe  87  and a threaded lateral tube  95  extending from valve section  93 . A handle  97  at the upper end of shutoff valve  91  can be rotated to open or close valve  91 . When valve  91  is open, water is allowed to flow from pipe  87 , through valve section  93 , and out of tube  95 . 
     Valve  47  has a valve body having a threaded connector  99  and a threaded end  101  on the opposite end of the valve body. Connector  99  connects valve  47  to tube  95  of shutoff valve  91 , and conduit  39  is connected to threaded end  101  with connector  103 . Conduit  39  is preferably a flexible hose, but conduit  39  may be any type of tube normally used to carry water. 
     A solenoid  105  is connected to a valve gate  107  for moving gate  107 , which engages a narrowed section  109  of the water flow path within the valve body. A spring  111  biases gate to the down, or closed, position shown in FIG.  3 . When in this position, gate  107  prevents fluid from flowing through valve  47  and into conduit  39 . Timer  65  is optionally mounted to valve  47  for limiting the amount of time solenoid  105  remains energized and/or for delaying the opening of gate  107  by delaying the energizing of solenoid  105 . The time limit prevents valves  47 ,  49  from remaining open indefinitely in the case where a conduit  39 ,  41  bursts during filling of the washing machine. Wires  51 ,  55  provide electrical power for operating solenoid  105  and timer  55 , electrical power being provided solely from the power supplied to solenoid  21 . 
     Referring to the figures, in operation, valves  47 ,  49  are installed between shutoff valves  91  and conduits  39 ,  41 , and wires  51 ,  55  and  59 ,  63  are connected to wires  45 ,  77  and  43 ,  75 , respectively, in the washing machine. Timer  13  is then manipulated by a user to start a wash cycle, and, at various points in the cycle, timer  13  causes an electrical current to flow to one or both solenoids  19 ,  21  for opening valves in valve assembly  69 . A portion of the current flows through wires  51 ,  55  and/or  59 ,  63  to valves  47 ,  49 . The current energizes solenoid  105  in the corresponding valve  47 ,  49 , lifting each gate  107  for allowing water to flow from pipe  87 , through shutoff valve  91 , through valve  47 ,  49 , and into a conduit  39 ,  41 . The water flows through conduit  39 ,  41  into an inlet  71 ,  73  and through valve body  69  to enter the washing machine. If a timer  65 ,  67  is used, timer  65 ,  67  operates to delay the energizing of solenoid  105  in each valve  47 ,  49  and/or stops the flow of current through solenoid  105  after a specified amount of time. 
     There are several advantages realized from using the present invention. The safety valves may be used with any appliance having electrically operated inlet valves for controlling the flow of water into the appliance. The safety valves do not require additional electrical power, since they are wired to the inlet valves of the appliance. Because the safety valves open when the appliance opens the inlet valves, no additional controller is needed. Installation is straightforward and simple, the safety valves being connected to the existing wiring of the appliance. A timer module may delay the energizing of the solenoid of each safety valve to limit the instantaneous current draw, and the timer may be used to limit the amount of time that the safety valve remins open. 
     While the invention has been shown in only one of its forms, it should be apparent to those skilled in the art that it is not so limited, but is susceptible to various changes without departing from the scope of the invention.