Abstract:
A switch having an automatic shut-off feature which turns off the switch after a defined period of time has elapsed. The invention has additional override features which allow the user to selectively override the automatic shut-off feature. The override feature can be a simple button or switch which the user can manually actuate. The override feature can also be remotely controlled using a hard-wired control line tied to an auxiliary panel, or a wireless control device such as a radio or ultrasonic link.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    This invention relates generally to the field of electrical control devices. More particularly, the present invention comprises a switch for light, fan or any switched controlled device, having an automatic shut-off feature and an override feature for modifying or turning off the shut-off feature. 
         [0003]    2. Description of the Related Art 
         [0004]    The concept of a switch having an automatic shut-off feature is described and claimed by the present inventor in U.S. Pat. No. 7,525,058 (2009) to Daffin, which is hereby incorporated by reference. Such a switch preferably fits within the prior art switch boxes so that they may be retrofitted into existing installations and easily installed using existing equipment. 
         [0005]    The switch disclosed in the Daffin &#39;058 patent is effective for its intended purpose. However, there are instances when the automatic shut-off feature is unwanted. Some users may wish to override the shut-off feature in certain circumstances or—depending on the user&#39;s preference—in all circumstances. It is therefore desirable to produce a light switch having a shut-off feature having other features which also allow the shut-off feature to be modified or turned off altogether. The present invention provides these features, as well as others. 
       BRIEF SUMMARY OF THE PRESENT INVENTION 
       [0006]    The present invention comprises a switch having an automatic shut-off feature which turns off the switch after a defined period of time has elapsed. The invention has additional override features which allow the user to selectively override the automatic shut-off feature. The override feature can be a simple button or switch which the user can manually or remotely actuate. The override feature can also be remotely controlled using a hard-wired control line tied to an auxiliary panel, or a wireless control device such as a radio, ultrasonic link or wave frequency. 
         [0007]    In some instances the override feature may be automated. Preferred embodiments include human presence sensors, such as heat, motion detectors or future detection device(s). These sensors detect the presence of an occupant in a room and suppress the automatic shut-off feature for the lights in that room until the occupant departs. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0008]      FIG. 1  is an exploded perspective view, showing a switch assembly made according to the present invention being installed in a prior art switch box. 
           [0009]      FIG. 2  is a perspective view, showing the opposite side of the switch assembly of 
           [0010]      FIG. 3  is a detailed perspective view, showing the provision of indicator and override features on the switch assembly. 
           [0011]      FIG. 4  is a schematic view, showing some of the internal operating features of the present invention. 
           [0012]      FIG. 5  is a perspective view, showing dial setting. 
           [0013]      FIG. 6  is a perspective view, showing “override controls” and time set controls. 
           [0014]      FIG. 7  is a schematic view, showing an integrated application system with invention and controlled device. Which is a light in this example application. 
           [0000]    
         
           
                 
               
                 
                 
                 
                 
               
             
                 
                     
                 
                 
                   REFERENCE NUMERALS IN THE DRAWINGS 
                 
                 
                     
                 
               
               
                 
                     
                 
               
            
             
                 
                   10 
                   toggle switch 
                   12 
                   switch assembly 
                 
                 
                   14 
                   switch box 
                   16 
                   cover plate 
                 
                 
                   18 
                   timer control knob 
                   20 
                   black wire connection 
                 
                 
                   21 
                   white wire connection 
                   26 
                   illuminated button 
                 
                 
                   28 
                   recessed switch 
                   30 
                   electrical load 
                 
                 
                   32 
                   power relay 
                   34 
                   transformer/rectifier 
                 
                 
                   36 
                   override control(s) 
                   38 
                   timer/controller 
                 
                 
                   40 
                   LED controller 
                   42 
                   pulse timer 
                 
                 
                   44 
                   LED 
                   46 
                   override control line 
                 
                 
                   48 
                   indicator control line 
                   50 
                   remote input line 
                 
                 
                   52 
                   remote panel 
                   54 
                   receiver 
                 
                 
                   56 
                   wireless remote 
                   58 
                   occupancy sensor 
                 
                 
                   60 
                   slot 
                   62 
                   rocker switch 
                 
                 
                   64 
                   controlled device 
                 
                 
                     
                 
               
            
           
         
       
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0015]      FIG. 1  shows a prior art switch box  14  and associated cover plate  16 . The switch box is conventionally mounted to a wall stud. Its opening is then surrounded by wall covering. A conventional light switch would then be installed in the opening and cover plate  16  would be installed over the switch. The present invention—designated as switch assembly  12  in the view—is preferably sized to be substituted for the prior art switch so that the existing hardware can still be used. 
         [0016]    Switch assembly  12  includes toggle switch  10  which a user can employ to control a light or other device. The toggle switch is conventionally “off” when toggled down and “on” when toggled up. Those skilled in the art will know that many different typed of user-actuated switches are known in the art. Examples include rocker switches, push-button switches, and capacitive switches which do not move and are actuated instead by skin contact. Any type of user-actuated switch can be selected for switch assembly  12 , so the toggle switch illustrated should be viewed as exemplary. 
         [0017]    The switch assembly includes an automatic shut-off feature. When the user flips toggle switch  10  to the “on” position, a timer function is started. When a predetermined amount of time has elapsed, the automatic-shut-off feature shuts off the light switch. The shut-off feature can be a mechanical device such as a solenoid (which would physically propel toggle switch  10  back to the “off” position), an electrical device (such as a control relay), or some combination of the two. 
         [0018]    The predetermined amount of time which the light switch remains on is preferably variable. Timer control knob  18  may be provided so that the user can easily adjust the amount of time the light will stay on (such as between 1 minute and 10 hours, for example). Or fixed time could be built into individual switches. Push buttons and other user-interface features could be substituted for the timer control knob and the particular approach taken is not significant to the present invention. 
         [0019]    Two black wire connections  20  are provided on the side of the switch assembly facing the viewer in  FIG. 1 . These are shown as screw terminals but may be of any known type. Those skilled in the art will know that in residential wiring the “black wire” is the hot wire which typically carries 110 VAC. The switch assembly makes or breaks a connection between the two black wire connections  20  (thereby establishing and breaking the circuit). 
         [0020]      FIG. 2  shows a perspective view of the opposite side of switch assembly  12 . In some embodiments it is desirable to provide a complete AC circuit connection to the switch assembly. This would include the black “hot” wire and the white “neutral” wire. Thus, a white wire connection  21  is preferably provided (two or more connections may optionally be provided). 
         [0021]    In operation, a user flips toggle switch  10  to the “on” position, thereby providing power to the electrical load controlled by the switch assembly. Flipping the switch “on” starts the timing function. When the predetermined amount of time expires, the automatic shut-off feature breaks the connection between the two black wire connections  20  (again this may be done by physically moving the toggle switch or using some other device such as a power transistor, mechanical device, clock, digital or power relay). If the switch is controlling a light, the light will go dark. 
         [0022]    At this point it is preferable to provide the user with some type of indication that the automatic shut-off feature has shut down the switch (otherwise the user may assume that a breaker has tripped or the light bulb has failed). An indicator can assume many forms. One example would be a “flag” type of display such as used on circuit breakers. However, because the room in which the switch is located will likely be dark, it is preferable to provide an illuminated indicator, such as a LED. 
         [0023]      FIG. 3  shows a detailed perspective view of the toggle switch  10 . In this embodiment, illuminated button  26  is provided on the toggle switch&#39;s tip. The button is molded out of transparent or translucent material and a light emitting diode (“LED”) is contained within. When the automatic shut-off feature is actuated, the LED is illuminated. Thus, a user standing in a suddenly darkened room will immediately notice the LED. 
         [0024]    An LED controller can be used to selectively pulse the LED or provide other visual effects. As an example, immediately after the actuation of the automatic shut-off feature, the LED could be brightly pulsed at a rapid rate. This would immediately attract the attention of any person in the room. Of course, it is likely that no one will be in the room and as the switch is designed in part to conserve energy, it makes sense to decrease the intensity and frequency of the LED flashes. After pulsing brightly for 30 seconds the LED controller might reduce the intensity and reduce the frequency to one flash every two seconds. 
         [0025]    The present invention recognizes that the automatic shut-off feature can at times be an inconvenience. An override function is provided to address this problem. When a user actuates the override function, the automatic shut-off feature is discontinued. As one example, illuminated button  26  can be a combination indicator and override actuation button. When the user sees the LED flashing, he or she can walk over and press illuminated button  26 . This will discontinue the automatic shut-off feature and allow the light switch to be operated normally. 
         [0026]    The actual effect of pressing the illuminated button will depend upon the type of automatic shut-off feature used. While it is impossible to go through every potential example, two quick examples may aid the reader&#39;s understanding: (1) If the automatic shut-off includes a mechanical feature that actually moves toggle switch  10  back to the “off” position, then the user will need to press illuminated button  26  and then physically flip the toggle switch to the “on” position; (2) If the automatic shut-off feature interrupts power without moving the toggle switch, then the user pressing illuminated button  26  would cause a light controlled by the switch to immediately illuminate. 
         [0027]    The override function can be actuated in an endless variety of ways and the invention is not limited to any particular embodiments.  FIG. 3  shows an alternate embodiment labeled as recessed switch  28 . A small hole in the cover plate is provided which aligns with this recessed switch. A small and pointed object such as a pencil or pen point can be used to actuate recessed switch  28  and thereby actuate the override function. 
         [0028]      FIG. 4  shows an exemplary circuit for implementing the proposed invention. Those skilled in the art will know that the invention could be implemented in a virtually endless variety of ways, using an equally various list of components. Switch assembly  12  preferably includes everything within the dashed lines. The version of  FIG. 4  uses power relay  32  to make or break the AC circuit to electrical load  30  (in this case a light bulb). The power relay terminals are labeled according to convention ( 85 / 86  and  87 / 30 ). Terminals  85  and  86  are the low current “control” side of the relay. Terminals  87  and  30  are the high current “power” side of the relay. Making or breaking the circuit flowing through terminals  85  and  86  makes and breaks the high-current circuit flowing through terminals  87  and  30 . 
         [0029]    This embodiment uses low voltage direct current for switching and control functions. The low voltage DC is conveniently produced by installing transformer/rectifier  34  across the white and black AC wires. This steps down the voltage and preferably removes most of the AC wave to produce a fairly smooth DC output. As shown, the DC output has a positive rail and a negative rail. 
         [0030]    Toggle switch  10  is installed across the DC rails in series with power relay  32 . Timer/controller  38  is also installed in series in the same current loop. When the user closes toggle switch  10 , the power relay provides AC current to electrical load  30 . This action also starts timer/controller  38 . The timer controller “counts” until a predetermined amount of time has passed. It then opens the circuit passing through terminals  85  and  86 . This—in turn—opens the circuit passing through terminals  87  and  30 . 
         [0031]    Timer/controller  38  actuates indicator control line  48  which—in this embodiment—provides voltage to LED controller  40 . The LED controller and pulse timer  42  then begin pulsing LED  44  (which may be within illuminated button  26  or at some other visible location). 
         [0032]    If a user then closes override switch  36 , override control line  46  provides voltage to another terminal on timer/controller  38 . This “informs” the timer/controller that the override function has been activated. The timer/controller then (1) shuts down the voltage on indicator control line  48 ; and (2) reestablishes the circuit across terminals  85  and  86  so that electrical load  30  is switched back on. In this embodiment, the toggle switch is not physically moved by the automatic shut-off feature. Thus, when the override function is actuated the light will be immediately turned back on. 
         [0033]    In some embodiments the override function will not be actuated by a device mounted directly on the switch assembly. Remote input line  50  to timer/controller  38  is provided for this purpose. As one example, a remote lighting control panel  52  may be provided at a convenient location in the house. This panel could control the override function on two or more switch assemblies. Actuating a feature on the remote panel would supply voltage to remote input line  52  and this would cause timer/controller  38  to actuate the override function as described previously. 
         [0034]    Other control means can be used to remotely activate the override function. Radio frequency receiver  54  can be used to create a signal on remote input line  50  when a coded message is sent from wireless remote  56 . 
         [0035]    Still another approach is to provide one or more occupancy sensors  58 . This component is any sensor capable of detecting the presence of a person in an area. For example, ultrasonic motion detectors or infra red body heat detectors could be used. In the event that an occupant is detected, a voltage is applied to remote input line  50  and this automatically actuates the override function. Thus, if an occupant is present in a room controlled by a switch, then the override function can be automatically activated. 
         [0036]    Many other variations are possible within the scope of the invention. For example, it may be desirable to provide access to the timing function without removing the cover plate.  FIG. 5  shows a perspective view of such an embodiment. Timer control knob  18  is made larger and protrudes through slot  60  in cover plate  16 . The user may easily increase the predetermined time by rotating the timer control knob as shown. The override function can also be incorporated into the timer control knob by rotating the exposed portion downward to the “off” position. 
         [0037]    Although the preceding descriptions contain significant detail they should not be viewed as limiting the invention but rather as providing examples of the preferred embodiments of the invention. As a first example, the override function could be actuated by other suitable means, such as switching the toggle switch on and off three times in three seconds. As a second example, the timer could be a mechanical timer or a digital “counter.” Accordingly, the scope of the invention should be determined by the following claims, rather than the examples given.