Abstract:
An exit alarm system housed in an escutcheon for activating upon movement of an interior latch operator. The system is mounted to the interior side of a door with a latch assembly including an interior latch operator. The system may include an alarm, a trigger, and an electronic module. The trigger is responsive to movement of the interior latch operator. The electronic module may be electrically connected to a power source for providing an input signal to the alarm. Upon motion of the interior latch operator, the trigger may cause the electronic module to send an activating input signal to the alarm. The alarm may be a sound transducer. A switch may be provide to arm the system. A tamper switch may be provided to cause the electronic module to activate the alarm upon removal of the escutcheon. The system may be applied to retrofit an existing door.

Description:
BACKGROUND 
     This invention relates to the field of exit alarms for doors, and more particularly concerns concealment of an exit alarm assembly in an escutcheon. 
     Various types of exit alarms, which sound as a door is opened from the inside, have been used effectively as a means of egress control. Examples of the various types include standalone box alarms, paddle arms, exit devices with integrated alarms, delayed egress exit devices, and others. While allowing egress, the alarm function deters the use of an opening except under emergency situations such as a fire, natural disaster, or manmade crisis. 
     The type of alarm unit used depends on the type of occupancy for which the building was designed. When the opening is to be used for egress as part of life-safety codes, an exit device, such as a device with a crossbar or flatbar operator, or similar panic device may be used and could contain an integral alarm function. When the occupancy is low or the opening is not considered to be a path of egress for life-safety, other locks, for example, mortise or cylindrical locks, may be used. Current practice provides for use of such locks in conjunction with a box alarm that is mounted separately on the door and frame, although other more complicated solutions are available that require hardwiring to external power sources. The resulting opening is fully functional, but the box alarms are unsightly and require additional installation time. In addition, identifying sources for and correctly installing separate products takes a significant amount of coordination, cost, and effort. 
     Accordingly, there exists a need for an alarm that is aesthetically pleasing and housed in a single unit. Ideally, the alarm unit may be standalone or designed to be connected to an external power source. 
     SUMMARY 
     In accordance with an embodiment of the present invention, an exit alarm escutcheon system for a door latch assembly for a door is provided. The door has an interior side and the latch assembly includes an interior latch operator. A housing is adapted to be mounted to the interior side of the door, and an alarm and trigger are disposed within the housing. The trigger is adapted to be actuated by movement of the interior latch operator. Actuation of the trigger causes a signal to be sent to the alarm to put the alarm into operation. 
     In accordance with another embodiment of the present invention, an exit alarm escutcheon system for a door latch assembly for a door is provided. The door has an interior side and the latch assembly includes an interior latch operator. A housing is adapted to be mounted to the interior side of the door, and an alarm is disposed within the housing. A trigger is adapted to be disposed in the door and is adapted to be actuated by movement of the interior latch operator. Actuation of the trigger causes a signal to be sent to the alarm to put the alarm into operation. 
     In accordance with another embodiment of the present invention, an exit alarm escutcheon system for a door latch assembly for a door is provided. The door has an interior side and the latch assembly includes an interior latch operator. A housing is adapted to be mounted to the interior side of the door, and a sound transducer, electronic module, trigger, and toggle switch are disposed within the housing. The electronic module is for providing an input signal to the sound transducer. The trigger is adapted to be actuated by movement of the interior latch operator. Actuation of the trigger causes a signal to be sent to the sound transducer to put the sound transducer into operation. The toggle switch in a first position arms the system to be capable of putting the sound transducer into operation and in a second position disarms the system so that the system is incapable of putting the sound transducer into operation. The electronic module is electrically connected to and signals the toggle switch, such that in the first position the toggle switch signals back to the electronic module, and in the second position the toggle switch does not signal back to the electronic module. The movement of the interior latch operator causes the trigger to signal the electronic module, causing the electronic module to send an input signal to the sound transducer to put the sound transducer into operation. 
     In accordance with another embodiment according to the present invention, an exit alarm escutcheon system for a door latch assembly for a door is provided. The door has an interior side and the latch assembly includes an interior latch operator. The exit alarm escutcheon system includes means for arming the system, means for actuating a trigger, means for signaling an electronic module, and means for putting an alarm into operation. 
     In accordance with another embodiment according to the present invention, an interior-side alarmed exit door system includes a door having an interior side and including a latch assembly including an interior latch operator. A housing is adapted to be mounted to the interior side of the door, and an alarm and a trigger are disposed within the housing. The trigger is adapted to be actuated by movement of the interior latch operator. The actuation of the trigger causes a signal to be sent to the alarm to put the alarm into operation. 
     In accordance with another embodiment of the present invention, a method of operating an exit alarm escutcheon system is provided. The method includes arming the system, actuating a trigger, signaling an electronic module, and putting an alarm into operation. 
     In accordance with another embodiment of the present invention, a method of making an exit alarm escutcheon system for a door latch assembly is provided. The door has an interior side and the latch assembly includes an interior latch operator. The method includes providing a housing adapted to be mounted to the interior side of the door. An alarm, trigger, and electronic module are all provided and are disposed within the housing. The trigger is adapted to be responsive to movement of the interior latch operator. The electronic module is for providing an input signal to the alarm. The alarm and the trigger are electrically connected to the electronic module. 
     In accordance with another embodiment of the present invention, a method of making an exit alarm escutcheon system for a door latch assembly is provided. A door is provided and has an interior side and the latch assembly includes an interior latch operator. A housing is mounted to the interior side of the door, and an alarm and an electronic module are disposed within the housing. The electronic module is for providing an input signal to the alarm. A trigger is adapted to be responsive to movement of the interior latch operator, disposed within the housing. The alarm and the trigger are electrically connected to the electronic module. 
     Features and advantages of the present invention will become more apparent in light of the following detailed description of some embodiments thereof, as illustrated in the accompanying figures. As will be realized, the invention is capable of modifications in various respects, all without departing from the invention. Accordingly, the drawings and the description are to be regarded as illustrative in nature, and not as restrictive. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an embodiment of an exit alarm unit according to the present invention installed on a door and with a latch operating lever. 
         FIG. 2  is a side elevation view of an escutcheon of the exit alarm unit of  FIG. 1 . 
         FIG. 3  is a front elevation view of the escutcheon of  FIG. 2 . 
         FIG. 4  is a partially exploded front perspective view of the exit alarm unit and latch operating lever of  FIG. 1 . 
         FIG. 5  is a partially exploded rear perspective view of the exit alarm unit and latch operating lever of  FIG. 1 . 
         FIG. 6  is a partially exploded rear perspective view of the exit alarm unit and latch operating lever of  FIG. 1 . 
         FIG. 7  is a front elevation view of the arming mechanism of the exit alarm unit of  FIG. 1 . 
         FIG. 8  is a front elevation view of another embodiment of an exit alarm unit according to the present invention. 
         FIG. 9  is a front elevation view of yet another embodiment of an exit alarm unit according to the present invention. 
         FIG. 10  is a schematic diagram showing the electrical elements of the exit alarm unit of  FIG. 1 . 
     
    
    
     DESCRIPTION 
     In the Figures herein, unique features receive unique reference numerals, while features that are the same in more than one drawing receive the same reference numerals throughout. Further, certain terms of orientation may be used, such as “upper,” “lower,” “top,” “bottom,” “left,” “right,” “inside,” “outside,” “interior,” “exterior,” “inner,” and “outer.” These terms are generally for convenience of reference, and should be so understood unless a particular embodiment requires otherwise. 
     The scope of the invention is not intended to be limited by materials listed herein, but may be carried out using any materials that allow the construction and operation of the present invention. Materials and dimensions depend on the particular application. In general the materials of the components may be metal, and selectively may be plastic, as known by one of ordinary skill in the art. 
     Referring now to the drawings, an embodiment of an exit alarm unit  20  according to the present invention is shown in  FIG. 1 . The exit alarm unit  20  is mounted to a door  22  and has a latch operator  24  passing therethrough and an associated latch assembly with a latch  26  and a cover plate  28 . The operator  24  is shown as a lever, but could be a knob, handle, or the like. The exit alarm unit  20  maybe used with a variety of locks (not shown), including but not limited to mortise and cylindrical locks. Further, the exit alarm unit  20  may be used not only on a door for a new installation, but may be retrofitted to an existing door. For a retrofit application, the exit alarm unit  20  may be provided, for example, as a kit, and may allow a door with mechanical locking and latching to be changed to an alarmed opening for greater control and security, similarly to a new installation. 
     The exit alarm unit  20  includes an escutcheon comprising a housing  30 , a keyed actuator or cylinder  32 , an indicator  34 , and a louver  36  to allow passage of sound. The housing  30  may be, for example, ABS plastic. The indicator  34  may be a light source such as a light emitting diode (LED) or a standard lamp. Screws  38  at each corner of the housing  30  secure the unit  20  to the door  22 . 
       FIGS. 2 and 3  show the housing  30  of the escutcheon. The housing  30  has a keyed actuator opening  40 , an indicator opening  42 , a spindle opening  44 , and the louver  36 . The thickness of the housing  30  increases in the portion above the spindle opening  44  to accommodate internal components. 
     Components internal to the housing  30  include an alarm assembly  50 , an activation ring  52 , and a battery holder  54 , as shown in  FIGS. 4-6 . The battery holder  54  may be fastened to the housing  30  with screws  56  or omitted and replaced with hardwiring to an external power source. A plate  58  may be interposed between the housing  30  and the door  22 . A bearing  60  may be mounted within the spindle opening  44  for journaling a smaller diameter portion of the latch operator  24  within the casing of the housing  30 . A spindle  62  integral with the lever  24  extends into the housing for operating the latch  26 , as is conventional. The alarm assembly  50  includes an alarm  72 , an arm/disarm switch  74 , the lamp/LED or indicator  34 , and an electronic module  76  to which the other components are mounted. The alarm  72  may be a sound transducer  72 . Alternatively, the alarm  72  may take other forms, such as a light source or a generator  77  of a wireless signal  78  to be received at a location  79  external to the housing  30 , such as at a remote location. The alarm assembly  50  may be fastened to the housing  30  with screws  84 . 
     Electrical components of the escutcheon may signal each other by either sending a signal when a lack of a signal is the default condition, or by stopping to send a signal when the presence of a signal is the default condition. For example, a switch that is open in the default condition, making the circuit open, may close to send a signal to another component, thereby signaling that component. A switch that is closed in the default condition, making the circuit closed, may open to stop sending a signal to another component, thereby signaling that component. 
     The arm/disarm switch  74  may be a toggle switch, as shown in the Figures, or another type of switch as selected by one of ordinary skill in the art. As will be described below, the prongs  80 ,  82  on the activation ring  52  may be adapted to toggle the arm/disarm switch  74  upon rotation of the activation ring  52 . 
     The electronic module  76  can be or can include (1) a circuit board having a single, custom integrated circuit and supporting components mounted thereon, (2) multiple interconnected discrete components or integrated circuits, or (3) a combination of multiple discrete components and multiple integrated circuits mounted thereon. Electrical wiring is omitted from the figures for clarity. 
     A trigger switch (not shown) is provided that detects movement of the latch operator  24 . The trigger switch may be selected as known by one of ordinary skill in the art and is conventional, for example, a microswitch, and may be located in a lockbody case in the door  22  or within the housing  30  adjacent the operator  24 . Detection of movement of the spindle  62  may, for example, be through the use of a cam on the spindle that then engages the switch. The trigger switch closes to trigger the alarm when the operator  24  is moved or rotated to open the door  22 . 
     A tamper switch  90  may also be provided in the housing  30 . The tamper switch  90  includes an arm  92  that is biased against the plate  58  when the housing  30  is mounted to the door  22 . When the unit  20  is armed, the removal of the unit  20  from the door  22  actuates the tamper switch  90  as the arm  92  is no longer biased against the plate  58 , activating the sound transducer  72 . 
       FIG. 7  shows the alarm assembly  70 , the activation ring  52 , and the keyed actuator  32  arranged as in the housing  30 . The unit  20  is armed and disarmed by moving the arm/disarm switch  74  between the on and off positions by rotation of the activation ring  52 , which is caused to rotate by the keyed actuator  32 . Specifically, the keyed actuator  32  has a rotatable offset portion  94  that extends into the housing  30 . An arm  96  integral with the offset portion  94  extends transversely to the axis of rotation of the offset portion  94 . As shown in  FIG. 7 , the switch  74  is toggled to the left, and the right prong  80  of the activation ring  52  is in contact with the switch  74 . To toggle the switch  74  to the right, a key (not shown) is inserted into the keyway in the keyed actuator  32 . The offset portion  94  of the keyed actuator  32  is rotated  98  counterclockwise with the key, with the keyed actuator arm  96  causing the activation ring  52  to rotate  100  as well until the left prong  82  contacts the switch  74 , pushing it to the right position. Alternative ways of actuating the switch  74  and alternative types of switches may be used as known by one of ordinary skill in the art. In addition, alternative ways of providing a secure method of control of the actuating mechanism may be used. For example, instead of being key-actuated, the arm/disarm switch may be a keypad-actuated switch that closes in order to arm the system when the appropriate code is entered. 
       FIGS. 8 and 9  show alternative embodiments of exit alarm units. The exit alarm unit  110  of  FIG. 8  includes a keypad  112  to actuate an arm/disarm switch. The exit alarm unit  120  of  FIG. 9  includes a magnetic reader device such as a card-swipe device  122  or smart card device for the same purpose. 
       FIG. 10  is a diagram of circuitry  130  that enables the alarm system to function. In example embodiments this circuitry can be at least partially located in the housing  30 . The electronic logic required is straightforward and well within the design capabilities of an engineer or technician of ordinary skill in the electronic arts. 
     The electronic module  76  drives the indicator  34  and the sound transducer  72  to produce the appropriate visual and/or audible signals. The electronic module  76  obtains power from the battery  132 . It should again be noted that a power source other than a battery could be used, and that power may be supplied by external means. The indicator  34  could be made to flash at different rates by appropriate logic contained in the electronic module  76 , for example, flashing 30 milliseconds when the unit  20  is first armed and then once every 30 seconds. The output states of the indicator  34  and sound transducer  72  are determined by logic in the electronic module  76  according to the states of the tamper switch  90 , arm/disarm switch  74 , and alarm trigger switch  134 . Assuming the logic of the electronic module  76  is designed to work with normally open switches, the tamper switch  90  is designed to close when the housing is opened or otherwise moved or damaged, the arm/disarm switch  74  is designated to close when the unit  20  is armed, and the trigger switch  134  is designed to close when the interior latch operator  24  is rotated. 
     It should be noted that either normally open or normally closed switches of various kinds could be used in the design described above. Also, there could be multiple switches for any of these functions. For example, if the enclosure of the lock system was such that two tamper switches would be needed, normally open switches connected in parallel or normally closed switches connected in series could be used. With some logic designs, one or more switches may need to be of the multiple pole and/or multiple throw type. The design options for circuitry  130  of  FIG. 10  are almost endless, and  FIG. 10  is intended to present but one example only. 
     Specific embodiments of an invention are described herein. One of ordinary skill in the lock and security hardware arts will recognize that the invention has other applications in other environments. In fact, many embodiments and implementations are possible. For example, the escutcheon of the present invention may be made in different shapes and sizes. The exit alarm unit may be configured to be used in other applications, such as windows. In addition, the recitation “means for” is intended to evoke a means-plus-function reading of an element in a claim, whereas, any elements that do not specifically use the recitation “means for,” are not intended to be read as means-plus-function elements, even if they otherwise include the word “means.” The following claims are in no way intended to limit the scope of the invention to the specific embodiments described.