Abstract:
A system and method for enabling automated activation of a temperature control shaft of a gas valve includes an electric motor having a motor shaft and integral coupler, wired to a relay control circuit and controlled by a standard electric timer device.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims priority from U.S. Provisional Patent Application No. 61/183,000 filed Jun. 1, 2009. The contents of U.S. Provisional Patent Application 61/183,000 are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to natural gas and propane water heaters and more particularly, an actuator apparatus utilized with a timer device to control the on and off operation of the water heater gas control valve to provide better efficiency to the operation of the gas water heater. 
     BACKGROUND OF THE INVENTION 
     Typically, gas water heaters are fueled by either natural or propane gas. The hot water heater provides a thermostat wherein the temperature within the hot water heater is maintained at a predetermined temperature established by the thermostat. When the water within the hot water heater reaches a temperature below the predetermined temperature set by the thermostat, the water heater begins to heat the water within the hot water heater until the water reaches the predetermined set temperature. 
     The continuous reheating of the water within the hot water heater is inherently an inefficient process because the water within the hot water heater is maintained at a predetermined temperature whether hot water is needed or not. 
     A more efficient operation would be to turn the water heater gas control valve off or to a lower setting during vacations, work schedules, evenings and other times when hot water is not needed. Thus the application of this invention will greatly reduce the consumption of fossil fuels and energy cost to operate a gas hot water heater. 
     SUMMARY OF THE INVENTION 
     Embodiments of the present invention resolve the above mentioned shortcomings by providing an actuator apparatus that can be used with a timer to programmably control the operation of a gas hot water heater. The apparatus is referred to herein as an actuator apparatus or assembly and consists of components to be coupled to the gas control valve of a gas hot water heater to operate at predetermined times that have been set on a programmable timer connected to the apparatus. Most conventional timer devices can be utilized with the actuator apparatus. The external power for the actuator apparatus and the timer is typically suppliant through the household AC system. 
     An actuator is a mechanical device for moving or controlling a mechanism or system. In embodiments of the present invention, the actuator apparatus or assembly is attached to a gas water heater valve for the purpose of controlling the operation of the water heater in accordance with settings of timer connected to the assembly. 
     In its basic configuration, the actuator apparatus is comprised of a motor having a motor shaft, a coupler attached to the motor shaft, an attachment component to affix the motor coupler to a gas control valve, an internal power supply and an electrical control system. 
     These and various other novel features and advantages of the present invention will be readily understood by those skilled in the related arts with reference to the following description taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is an exploded perspective view of the components of the gas water heater actuator apparatus and their relative order of position for attachment to a gas water heater temperature control valve. 
         FIG. 2  is a view of the coupler attached to a gas water heater temperature control valve. 
         FIG. 3  and  FIG. 4  show schematics of an embodiment of an electrical configuration for operating the apparatus. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIG. 1 , which shows the general features of a preferred embodiment of the invention, the actuator assembly  10  is shown in its orientation and position with respect to a typical gas water heater control valve  40 . In its basic form, the actuator assembly is comprised of a gear motor  14  capable of being connected to a gas water heater control valve  40  via use of a coupler  16  and support hardware. 
     The gear motor  12  as shown in  FIG. 1  typically contains at least one shaft  14  which can be used to connect to a coupler  16 . The coupler is connected to the gear motor shaft at one end and it has an opening  18  at the opposite end that is utilized to connect to the gas water heater control valve  40 . 
     The gear motor will typically fit into a gear motor housing  20  which in turn is contained within the first actuator housing  22 . The switch activation arm  24  is attached to the gear motor shaft  14 . Directional switches  25 ,  26  are mounted on the top of the first actuator housing  22 . The activator arm travels within the opening or slot  28  in the first actuator housing  22  to activate, actuate or trip the directional switches. An electrical wire harness (not shown) is connected to the directional switches. 
     The actuator assembly  10  is aligned with and connected to the gas valve  40  utilizing the actuator assembly mounting bracket  30  and the gas valve mounting bracket  32 . Bolts  34  are typically used with the brackets. 
     The gas water heater valve has a temperature control dial (not shown) that is attached to the gas valve temperature control shaft  42 . The temperature control shaft  42  typically has a protuberance  44  attached to or protruding from the temperature control shaft  42 .  FIG. 2  shows this protuberance  44  aligned with a notch or opening  18  on the coupler  16 . 
     To install the apparatus on a gas water heater, one would first determine if the temperature control dial is rotated clockwise to attain a higher temperature setting or counterclockwise. This will dictate which wiring harness to use. The schematic shown in  FIG. 3  represents the wiring harness assembly utilized when the higher temperature setting is achieved by rotating the temperature dial in a counterclockwise direction. The schematic shown in  FIG. 4  represents the wiring harness assembly utilized when the higher temperature setting is achieved by rotating the temperature dial in a clockwise direction. Assuming the correct wiring harness is present, one would utilize the following steps to install the apparatus. 
     Step 1: Turn the water temperature dial on the gas water heater valve to the lowest setting. 
     Step 2: Remove the water heater temperature dial from the gas valve. 
     Step 3: Align the actuator assembly so that the directional switches  25 ,  26  are facing up and the two mounting bolt holes in the mounting bracket  30  are approximately parallel to the floor. 
     Step 4: Rotate the motor shaft  14  with the switch activation arm  24  until the notch  18  in the coupler  16  is lined up with the shaft  42  and protuberance  44  on the water heater gas valve. 
     Step 5: Slide the gas valve actuator towards the gas valve. The coupler  16  will slide over the shaft on the gas valve and the protuberance  44  will be engaged within the notch  18  of the coupler  16 . 
     Step 6: Secure the two mounting bracket bolts  34  through the holes in the actuator assembly mounting bracket  30  and into the pre-threaded mounting bracket  32  positioned behind the gas water heater valve  40 . 
     Step 7: Plug the power cord (that supplies electricity to the power supply) into an external power supply (outlet). Plug the timer cord (that supplies power to the relay) into a timer that is set in the “OFF” position. Plug the timer into an external power (outlet). 
     Step 8: Set the timer to turn on and off as applicable. 
     The internal power supply is typically 5 VDC and remains powered at all times when the apparatus is connected to an external AC power supply. A 115V relay coil is controlled by the timer. When the timer is in the “ON” position, a relay coil is energized and a set of contacts close to pass 5V DC to the motor. The motor turns the gas valve in the appropriate direction to reach the desired heating setting (i.e., the counterclockwise direction ( FIG. 3 ) or the clockwise direction ( FIG. 4 )). When the gas valve is rotated to reach the desired heating setting the switch activation arm, having rotated along with the motor shaft, activates a directional switch which opens the relay directional control circuit and stops the motor. 
     When the timer is in the “OFF” position, the relay coil de-energizes; closing another set of contacts on the relay and opening the contacts for the other direction and the motor turns in the opposite direction until the switch activation arm activates the directional switch which opens the control circuit and interrupts the 5 Volts DC from the power supply and stops the motor. This deactivates the water heater gas valve. 
     A typical wiring setup is discussed herein presuming the wall plug is plugged in and the timer has been set and activated. On some water heaters, the temperature control dial is rotated in the counterclockwise direction to attain a higher temperature setting. The wiring schematic shown in  FIG. 3  would be utilized with an actuator when the counterclockwise temperature dial is present. The wiring schematic shown in  FIG. 4  is appropriate when the temperature control dial on the gas valve is rotated in the clockwise direction to attain a higher temperature setting for the water heater. 
     Utilizing the schematic in  FIG. 4 , the path of current can be traced from the negative terminal (−) on Power Supply (PS) to the positive terminal (+) on the PS to explain the operation of the valve timer. This will explain the operation of the valve electronics control that turns the gas valve off and on. 
     Using the  FIG. 4  (clockwise rotation=on) schematic diagram, start at the Negative (−) terminal at the Internal Power Supply P.S. (BLK wire). The BLK wire is connected to two devices, a relay at pin  6 , and the OFF LIMIT switch DS 2  at the Common (C) terminal. OFF LIMIT directional switch DS 2  corresponds to part # 26  in  FIG. 1 . The relay at pin  6  is a “Normally Open” contact. There will be no current passing through the relay at pin  6  because the contact is open. The other connection at the Common (C) terminal of the OFF LIMIT switch DS 2  is passing current to its “Normally Closed” (N.C.) contact, then to pin  4  of the relay (BRN wire). 
     Pin  4  on the relay is a Normally Closed contact connected to Pin  1  in the relay, which is connected to one of the motor terminals (WHITE wire) passing current to the motor. The other side of the motor is connected to pin  8  of the relay. (YEL wire) 
     Pin  8  of the relay is connected through a Normally Closed contact in the relay to pin  5 , which is connected to the positive side (+) RED wire of the internal power supply P.S. completing the circuit, driving the motor and moving the valve to the OFF position. 
     The red wire is also connected to the ON LIMIT switch DS 1  Common (C) terminal which is connected to its Normally Closed Contact, (BLU wire). But no current will flow in this direction, because pin  3  on the relay is Normally Open until the relay is activated. 
     When temperature control shaft on the gas valve reaches the position where the water heater setting is in the OFF position a switch activation arm (# 24  on  FIG. 1 ) will activate (open) the OFF LIMIT switch. When the OFF LIMIT switch opens, the current path to the motor is interrupted and the motor stops. 
     When the timer comes ON and sends 115 V AC to the relay coil [( 7 ) ( 2 )], the relay contacts change position (from ( 4 ) to ( 3 ) and from ( 5 ) to ( 6 )) and drive the motor in the opposite direction by allowing current to first pass from the negative terminal on the internal power supply (P.S.) through pin  6  of the relay to pin  8  of the relay. The armature on the relay has moved from pin  5  to pin  6  allowing current to pass to pin  8  which is wired to the motor. 
     The other side of the motor is wired to pin  1  on the relay (WHITE wire). Because the relay is actuated, the armature is moved to pin  3  from pin  4  which allows current to flow through the ON LIMIT switch DS 1  from the Normally Closed (N.C.) contact to the Common contact (C) which is wired to the positive terminal of the P.S. 
     The motor activation causes the temperature control shaft on the gas valve to rotate to where the water heater setting is in the ON position at which point the switch actuator arm  24  actuates the ON LIMIT switch which opens and interrupts the current flow and stops the motor. 
     When the timer shuts off, the relay reverses contacts and drives motor to OFF position again. This completes the cycle for actuating the valve assembly. 
     GLOSSARY OF TERMS 
     Activator Arm: A physical component attached orthogonal or approximately orthogonal to the motor shaft. The activator arm rotates along with the motor shaft and communicates with one or more sensors to facilitate operation of the motor. 
     Actuator: The actuator assembly encompasses at least the following basic components: a motor, motor shaft, activator arm, coupler, internal power supply and electronic control system. 
     Electrical switch component: The electrical switch components are typically directional switches that ultimately control the direction of the motor shaft and actuator arm however all equivalent electrical sensor components are contemplated. It is contemplated that only one directional switch could be utilized. The directional switches described herein are typically activated when contacted by the activator arm. Other types of electrical components are contemplated including optic and electrical sensors which may or my not necessitate physical contact with the activator arm to actuate, trip or communicate with the switch to activate the motor in response to the position of the activator arm. 
     Electronic control system: This system consists of the wiring and electrical components to control the movement of the motor and actuator arm to effectuate the desired movement of the gas water heater temperature control valve. 
     External power supply: This power supply is typically an AC power source but any type of power supply capable of providing power to the internal power supply is contemplated including, but not limited to, AC or DC power sources, e.g., generators, solar or wind power, and batteries. 
     Internal power supply: The internal power supply is typically a DC power supply or an AC transformer however any applicable power supply known by those skilled in the art is contemplated. 
     CONCLUSIONS, OTHER EMBODIMENTS, AND SCOPE OF INVENTION 
     A preferred embodiment of the control system has been shown and described herein. Another control system contemplated utilizes one double pole, double throw relay and a 115 volt AC coil. Another control system utilizes one 5 volt DC power supply that transforms 115 VAC into 5 volts DC to drive a DC motor. 
     This activator apparatus could also operate utilizing a low voltage reversing AC motor by replacing the power supply with a transformer and replacing the motor with an AC reversing motor. The wiring would be adapted to accommodate this configuration. The limit switches and relay could be utilized but would be rewired and a transformer would provide the internal power supply to replace the internal DC power supply. 
     Thus, although there have been described particular embodiments of the present invention of a new and useful device, it is not intended that such references be construed as limitations upon the scope of this invention except as set forth in the following claims.