Abstract:
A doorbell unit capable of displaying several status indicators or messages next to its activation button. The activation button is located on a display panel. The user can set the display panel to show a variety of messages, including “Do Not Ring,” “Ring With Care,” “Welcome,” or a custom text message. The display panel is preferably controlled by logic circuitry located within a controller, which replaces the conventional chime unit. A remote control is provided, so that the user can alter the status of the device without having to access the controller.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to the field of home accessories. More specifically, the invention comprises a doorbell which displays a status message informing a visitor whether the house is receiving guests. 
     2. Description of the Related Art 
     Electrical doorbells have been in common use for many decades.  FIG. 1  shows a typical prior art device. Chime unit  14  is mounted on a wall in the interior of a house, typically in a hallway. 110VAC is provided via line power  30 . Two wires run to activation button  12 , which is mounted next to the front door. The two wires comprise activation circuit  16 . When button  12  is pressed, a circuit is made and the tone generating chimes within chime unit  14  are activated. 
     The chime unit is typically loud enough to alert everyone in the home. Its activation can cause unwanted disturbance, however, in the case of sleeping infants. Since it often requires quite some time to induce sleep in an infant, once disturbed, the infant may remain awake for some time. Thus, an unwanted activation of chime unit  14  can be a big problem. It would therefore be advantageous to provide some indication as to whether visitors are welcome. 
     Those skilled in the art will know that the two wires comprising activation circuit  16  customarily carry a 10-16VAC potential. This potential is typically provided by a step-down transformer within chime unit  14 . In a sense, the activation circuit is always “made”, in that a light within the button is customarily powered by the activation circuit (thereby illuminating the button). However, the light source is a high resistance connection that allows very little current flow within the activation circuit. When the door bell button is pressed, this “makes” a low resistance connection which allows substantial current flow and the activation of the chime unit itself. The existence of the low-current 10-16VAC potential on the activation circuit is significant, since it can be used to power devices located proximate the door bell button. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention comprises a doorbell unit capable of displaying several status indicators or messages next to its activation button. The activation button is preferably located on a display panel. The user can set the display panel to show a variety of messages, including “Do Not Ring,” “Ring With Care,” “Welcome,” or a custom text message. The display panel is preferably controlled by logic circuitry located within a controller, which can replace the conventional chime unit. A remote control is provided, so that the user can alter the status of the device without having to access the controller. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         FIG. 1  is a perspective view, showing a prior art doorbell. 
         FIG. 2  is a perspective view, showing the display panel. 
         FIG. 3  is a perspective view, showing all the components of the present invention. 
         FIG. 4  is a perspective view, showing details of the controller. 
     
    
    
     
       
         
               
             
               
               
               
               
               
             
           
               
                   
               
               
                 REFERENCE NUMERALS IN THE DRAWINGS 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 10 
                 doorbell system 
                 12 
                 activation button 
               
               
                   
                 14 
                 chime unit 
                 16 
                 activation circuit 
               
               
                   
                 18 
                 display panel 
                 20 
                 red indicator 
               
               
                   
                 22 
                 yellow indicator 
                 24 
                 green indicator 
               
               
                   
                 26 
                 text display 
                 28 
                 controller 
               
               
                   
                 30 
                 line power 
                 32 
                 R/F receiver 
               
               
                   
                 34 
                 tone generator 
                 36 
                 remote control 
               
               
                   
                 38 
                 red button 
                 40 
                 yellow button 
               
               
                   
                 42 
                 green button 
                 44 
                 menu up button 
               
               
                   
                 46 
                 select button 
                 48 
                 menu down button 
               
               
                   
                 50 
                 menu display 
               
               
                   
                   
               
             
          
         
       
     
     DETAILED DESCRIPTION OF THE INVENTION 
     The preferred embodiment of the present invention is designed to directly replace the prior art activation button and chime unit.  FIG. 2  shows display panel  18 , which is installed in place of the prior art activation button. The display panel is electrically connected to the existing activation circuit  16 . The low-current AC voltage on the activation circuit is used to power the display panel. Activation button  12  provides the same function as in the prior art; i.e., if activation button  12  is pressed, the doorbell will ring. 
     The display panel features three indicators near the activation button: red indicator  20 , yellow indictor  22 , and green indicator  24 . One of the indicators can be illuminated in order to provide a “status” message to a visitor contemplating ringing the doorbell. In addition to the color cue, a text message can be provided with each indicator. The text message can be back-lit when the indicator is illuminated. Thus, for the red indicator, the message “DO NOT RING” can be included. For the yellow indicator, the message “RING WITH CARE” can be included. For the green indicator, the message “WELCOME” can be included. These particular messages are merely representative. Obviously, many different messages can be printed on the translucent cover of each indicator. 
     The display panel also includes a text display  26 . This is typically an LCD character display. The user is able to set this display to read a variety of user-defined messages. Thus, it might be set to read “COME IN, I&#39;M ROCKING THE BABY.” 
       FIG. 3  shows all the components as they would be installed. Display panel  18  replaces the prior art activation button. Controller  28  replaces the prior art chime unit. The controller and the display panel are electrically connected using the prior art activation circuit  16 . Nearly all houses have such an activation circuit in place. Thus, the present invention can be installed without running additional wiring. The controller is connected to line power  30 . It contains a step-down transformer, as for the prior art chime unit. 
     However, controller  28  contains more features than the prior art chime unit. It contains control circuitry for sending control signals to the display panel. The display panel likewise contains control circuitry. 
     The user conventionally employs remote control  36  to set the desired status of the display panel. Controller  28  features R/F receiver  32  to receive signals from the remote control (The particular communication method used is not important. Infrared or ultrasonic signal transmission could be used instead of radio frequency signals). The remote control has several buttons, including red button  38 , yellow button  40 , and green button  42 . The user presses these to activate the red, yellow, or green indicators on the display panel. The remote control also features a menu up button  44 , a menu down button  48 , and a select button  46 . 
     Turning to  FIG. 4 , the reader will observe that the lower part of controller  28  features menu display  50 . The controller is typically mounted high on a wall (such as in an entrance hallway). The user can look up at the controller and easily read menu display  50 . The user then presses the menu up or menu down buttons on the remote control to scroll through menu options. When the desired option is displayed, the user presses the menu select button. 
     The menu can be used to select a variety of standard messages for text display  26 . The menu can also be used to allow the user to create custom messages by scrolling through and selecting the letters in sequence. 
       FIG. 4  also illustrates the presence of a supplemental set of menu controls on the bottom of the controller, right next to menu display  50 . An additional menu up button  44 , menu down button  48 , and select button  46  are provided on the controller itself. If the remote control cannot be found (or if the user does not wish to use it), these supplemental buttons can be used to set the desired configuration for the controller. The reader should note that the wires shown coming out of the side of the controller in  FIG. 4  would not actually be visible. These would actually exit the rear of the unit and enter the wall on which the controller is mounted. The wires are shown as visible in  FIGS. 3 and 4  so that the user will understand the use of the existing activation circuit to communicate between the controller and the display panel. 
     Returning now to  FIG. 3 , some explanation of the communication between the controller and the display panel, as well as the internal operation of both of these components, may be helpful to the reader&#39;s understanding. The controller provides a low-current AC voltage over the activation circuit. This voltage provides power to the display panel. The display panel preferably includes digital control circuitry. The indicators are preferably powered by low-current devices such as LED&#39;s. 
     The controller includes digital control circuitry as well. When the user makes a selection (such as the command to illuminate the red indicator), the controller encodes this as a digital signal which is then transmitted over the activation circuit. This digital signal is decoded by the digital control circuitry in the display panel. A responsive power circuit then supplies power to the red indicator. Other signals can be transmitted to illuminate the yellow indicator, illuminate the green indicator, or provide a text message. All these signals can be carried on the activation circuit, on top of the low-current AC “power signal.” 
     When a visitor presses activation button  12 , a signal is sent back from the display panel to the controller. The controller then activates tone generator  34 , which sounds a desired tone (chime, buzz, or whatever the user prefers). The user is also allowed to set a lock-out feature, so that when the red indicator is illuminated, the tone will not sound. 
     The reader will thereby appreciate that the proposed invention provides a status display while still allowing the normal function of the prior art doorbell. The reader should be aware that although the preferred embodiment (disclosed in  FIGS. 2-4 ) suggests removing the existing activation button and chime unit, other embodiments can be conceived where this need not be done. 
     A display panel having no button can simply be mounted next to an existing activation button. It is then connected to the activation circuit in parallel with the existing button. Likewise, the user can leave the existing chime unit in place, simply connecting the controller in parallel with the chime unit. The controller and display panel can then communicate via digital signals transmitted over the activation circuit. However, the conventional function of the activation unit button and chime unit will be unaffected. Thus, the present invention can be a supplement to—rather than a replacement for—an existing doorbell system. 
     Although the preceding descriptions contain significant detail, they should be properly viewed as providing examples of the present invention, rather than limitations on the scope of the present invention. Accordingly, the scope of the invention should be set by the following claim rather than by any particular examples provided.