Abstract:
The present invention relates to a removable battery system for a smoke detector having a low battery detection circuitry and an audible alarm. The system includes a pair of battery receivers each adapted to receive a battery therein and being electrically coupled to the low battery detection circuitry and the audible alarm wherein at least one of the batteries provides constant power to the low battery detection circuitry and the audible alarm. The system further includes a cover that is selectively movable to provide access to the battery receivers and a locking mechanism coupled to the pair of battery receivers wherein upon failure of one of the batteries received in the pair of battery receivers that provides constant power to the low battery detection circuitry and the audible alarm, the low battery detection circuitry sounds the audible alarm and selectively activates the locking mechanism to prohibit movement of the cover.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     Not applicable.  
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
       [0002]     Not applicable.  
       BACKGROUND OF THE INVENTION  
       [0003]     This invention relates to an improved battery detection and alarm system, and more particularly to a removable battery system wherein upon failure of a battery, the failed battery must be replaced by a working battery before the audible alarm is silenced. The system may be used with any number of detection systems, some examples include smoke detectors, carbon monoxide alerting systems, and medical alerting systems. The following discussion, while relating specifically to smoke detectors, is not intended to limit the detection system.  
         [0004]     The invention of the residential smoke detector has been proven a lifesaver countless times. However, experience with these devices has revealed a serious deficiency. Typical smoke detectors in the industry either have a single replaceable battery system or are powered by a power source contained in the residence or building where they are located.  
         [0005]     The single replaceable battery system contains a single battery that upon failure emits a “chirping” sound to inform the user that the battery needs to be replaced. This design has the “human factor” problem in that the user must choose to replace the battery. However, the user may also choose to simply remove the battery to eliminate the “chirping” noise and, thus, the unit is rendered useless.  
         [0006]     Another common design is a smoke detector that is powered by the buildings utility source. However, these units also suffer from a number of drawbacks. First, these systems also contain batteries that eventually fail and need to be replaced. Further, detectors powered from the building utility source may fail from utility interruption or wiring failure. Still further, systems that depend on remote power supplies or larger building wide control panels often contain complex backup power supervision systems to prevent loss of power supply. These types of systems are complex and very expensive.  
         [0007]     Another design is the use of longer life batteries in the smoke detector. U.S. Pat. No. 5,444,434, August 1995, to Serby, discloses a smoke detector unit with a long life integral battery design with a claimed life up to 15 years. However, the device described by U.S. Pat. No. 5,444,434, to Serby, still contains a single battery that is not replaceable. Thus, if this battery fails, the device is no more usable than any other units with failed batteries.  
         [0008]     Another design is the use of multiple power sources. However, the self-contained smoke detector used in residential applications must be simple, low cost, and easy to install and operate. No present art exits utilizing multiple power sources that is simple, low cost, and easy to install and operate. U.S. Pat. No. 5,574,436, to Sisselman, proposed adding a supplemental internal battery or capacitor to power the alarm function. However, this approach contains a number of deficiencies. First, the Sisselman design requires a non-replaceable battery that when fails or wears out renders the detector useless. Further, the Sisselman design requires recharging the non-replaceable battery from the replaceable battery, which diminishes the available power to the detector.  
         [0009]     Thus, there remains a need for a detector alarm and a removable battery system that eliminates the “human factor” problem that is simple, low cost, and easy to install and operate. More specifically, there is a need in the smoke detector industry for a system that eliminates the “human factor” by providing an alarm system with a power source that is not silenced by simply removing a failed replaceable battery, only when the failed battery is replaced by a working battery.  
       BRIEF SUMMARY OF THE INVENTION  
       [0010]     Accordingly, it is the object of the present invention to provide a removable battery system that solves the “human factor” problem.  
         [0011]     It is a further object of the present invention to provide a removable battery system that is simple, low cost, and easy to install and operate.  
         [0012]     Accordingly, the present invention provides a removable battery system that solves the “human factor” problem by providing an alarm that is not silenced by removing a failed replaceable battery. The detector of the present invention includes a single or dual replaceable battery system that provides a persistent audible alarm whenever the battery supply fails or if the replaceable battery is removed. With the multiple battery configurations, multiple batteries are contained in the battery compartments with a sliding enclosure that ensures continuous battery power by allowing only a single battery to be removed at a time and requires the replacement to be a working battery. With the single battery system, a single battery is contained in one of the battery compartments with a sliding enclosure that ensures continuous battery power by allowing a failing battery in one of the compartments to be removed once a working battery has been inserted in the other battery compartment. By providing a continuous audible alarm, the user may simply not ignore the device as the alarm recurs until a failed battery is replaced by a working battery.  
         [0013]     Additional advantages, and novel features of the invention will be set forth in a description which follows, and will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention. 
     
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING  
       [0014]     In the accompanying drawings which form a part of the specification and which are to be read in conjunction therewith, and in which like reference numerals are used to indicate like parts in the various views:  
         [0015]      FIG. 1  is a perspective view of a smoke detector with a removable battery system;  
         [0016]      FIG. 2  is a side view of a smoke detector with parts being broken away to show particular details of construction;  
         [0017]      FIG. 3  is a top view of the removable battery system with cover in the working position;  
         [0018]      FIG. 4  is a top view of the removable battery system with cover indexed to the right position and solenoid armature energized;  
         [0019]      FIG. 5  is a top view of the removable battery system with cover indexed to the left position and solenoid armature de-energized;  
         [0020]      FIG. 6  is a top view of the removable battery system with cover indexed to the left position and solenoid armature energized;  
         [0021]      FIG. 7  is a perspective view of an electric block diagram;  
         [0022]      FIG. 8  is a second embodiment of the smoke detector with a removable battery system;  
         [0023]      FIG. 9  is a top view of the second embodiment of the removable battery system with cover indexed to the right position and solenoid armature energized;  
         [0024]      FIG. 10  is a top view of the removable battery system with cover indexed to the left position and solenoid armature energized; and  
         [0025]      FIG. 11  is a perspective view of the second embodiment of an electric block diagram. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0026]     Referring to the drawings in greater detail and initially to  FIGS. 1 and 2 , a smoke detector is shown and designated generally by the numeral  10 . While the discussion is focused on a smoke detector, it will be appreciated by one of ordinary skill in the art that the removable battery system may be used in a number of detection and alarm systems. Smoke detector  10  includes a housing  12  and a removable battery system  14 . Housing  12  is formed in the conventional manner, typically from injection molded plastic and is well known in the art. It should be understood that the housing  12  can be made from any other suitable material having similar characteristics.  
         [0027]     As further illustrated in  FIGS. 1-3 , removable battery system  14  broadly includes a battery compartment  16 , a sliding cover  18 , a pair of electrical contacts  20 ,  22  and a cover solenoid  24 . Battery compartment  16  consists of a pair of battery holders  26 ,  28 . As best seen in  FIG. 2 , battery holders  26 ,  28  are generally box-like and are sized for receipt of a pair of batteries  30 ,  32 . Battery holders  26 ,  28  contain polarized electrical contacts  34  and are configured as such so that batteries  30 ,  32  may not be improperly inserted. As seen in  FIGS. 1 and 2 , sliding cover  18  is slidably received within housing  12  to conceal battery compartment  16 .  
         [0028]     Referring now to  FIG. 3 , cover  18  is generally rectangular in nature with an outer edge  36  and an inner edge  38 . The inner edge  38  is also generally rectangular in nature and defines an opening  40 . Opening  40  is sized to only allow insertion of a battery in the correct orientation. Sliding cover  18  further includes a tab  42 , positioning notches  44 ,  46 , conductive metal strips  48 ,  50  and a positioning detent  52 . Tab  42  is molded to cover  18  at inner edge  38  and extends outwardly to facilitate movement of cover  18 . As further shown in  FIG. 3 , positioning notches  44 ,  46  are shown as generally rectangular recesses located on the perimeter of cover  18  at an intermediate position. Conductive metal strips  48 ,  50  are attached to the side of the cover  18  and are located near each end, the importance of which will be further described below. It will be appreciated that conductive metal strips  48 ,  50  can be made from any suitable conductive material as understood by one of ordinary skill in the art. The conductive metal strips  48 ,  50  on cover  18 , when engaged with the electrical contacts  20 ,  22 , form electrical switches  54 ,  56 , the importance of which will be further described below.  
         [0029]     Referring now to  FIG. 7 , an electronic block diagram of the present invention is shown. The electric block diagram generally consists of the pair of batteries  30 ,  32 , connected to the contacts  34  in the battery holders  26 ,  28 , a pair of battery test switches  54 ,  56 , a circuit board  58 , and a cover solenoid  24 . Circuit board  58  further includes smoke detector circuitry  60  and an audible alarm device  62 , both of which are well known in the art. Smoke detector circuitry  60  is well known in the art and generally includes an emergency smoke detector function such as a low battery indicator, not shown. Other smoke detector circuitry exists, specifically ionization, photoelectric, temperature, or carbon monoxide concentration detectors; however, it is not included as it is not pertinent to this discussion.  
         [0030]     The smoke detector circuitry  60 , i.e., the low battery indicator, monitors the available power of the batteries  30 ,  32  and activates the audible alarm  62  if the voltage of either of the batteries  30 ,  32  is deemed to be inadequate. Typically, to warn of a low battery condition, the audible alarm device  62  emits a “chirping” noise or other distinct recognizable sound. Some detector embodiments have voice alarms that provide a spoken indication of the low battery condition.  
         [0031]     Referring again to  FIG. 7 , batteries  30 ,  32  are electrically coupled to both the electrical switches  54 ,  56  and the smoke detector circuitry  60  in a manner well known in the art. Batteries  30 ,  32  supply power to circuit board  58  that contains the smoke detector circuitry  60 . The cover solenoid  24  is electrically coupled between the electrical switches  54 ,  56  and the smoke detector circuitry  60  in a manner well known in the art. Cover solenoid  24  is well known in the art and includes an armature  64 .  
         [0032]     It is appreciated by one of ordinary skill in the art that when viewing  FIGS. 4 and 7 , that the contacts  20  and the conductive metal strip  48  on the left portion of the cover  18 , along with the battery  32  in the right battery compartment  28 , combine to create the switch  56 . When viewing  FIGS. 5-7 , the contacts  22  and the conductive metal strip  50  on the right portion of the cover  18 , along with the battery  30  in the left battery compartment  26 , combine to create the switch  54 .  
         [0033]     Referring now to  FIGS. 3-6  the removable battery system  14  is shown. The housing  12  has been removed for clarity.  FIG. 3  shows the removable battery system  14  with sliding cover  18  in its working position and with armature  64  of solenoid  24  de-energized and engaged with positioning detent  52 .  FIG. 4  shows the removable battery system  14  with sliding cover  18  indexed to the right and with armature  64  of solenoid  24  energized and disengaged from positioning notch  44 .  FIG. 5  shows the removable battery system  14  with sliding cover  18  indexed to the left with armature  64  of solenoid  24  de-energized and engaged with positioning notch  46 .  FIG. 6  shows the removable battery system  14  with sliding cover  18  indexed to the left and with armature  64  of solenoid  22  energized and disengaged from positioning notch  46 . The importance of each of the above configurations will be discussed further below.  
         [0034]     Referring now to  FIGS. 3-6 , the operation of the removable battery system  14  will be described. As best seen in  FIG. 3 , smoke detector  10  is shown in its working position where with cover solenoid  24  is in its de-energized position with its armature  64  engaged with the positioning detent  52  to provide resistance to movement. Working batteries  30 ,  32 , shown in  FIG. 2 , have been properly inserted in battery compartments  26 ,  28  and smoke detector is functioning.  
         [0035]     When the smoke detector circuitry  60  indicates a low battery voltage condition, it activates the audible alarm device  62 , which emanates a “chirping” noise to warn of the condition. At this point the user must replace the failed battery with a working battery in order to eliminate the “chirping.” The user must either index the cover  18  to right or the left to gain access to the batteries  30 ,  32 . Referring now to  FIG. 4 , the removable battery system  14  is shown with the cover  18  indexed to the right. When the cover is indexed to the right to gain access to the battery holder  28 , an electrical circuit or switch  56  is completed when the conductive strip  48  contacts the electrical contacts  20 . If the battery  32  is of sufficient quality, the solenoid  24  will energize the armature  64 , as shown in  FIG. 4 , and the cover  18  may then be indexed back to its working position as shown in  FIG. 3 . The audible alarm device  62  constantly emits the “chirping” sound since the failed battery has still not been replaced. Once the cover  18  is indexed back to the working position of  FIG. 3 , the conductive strip  48  loses contact with the electrical contacts  20  and the electrical circuit or switch  56  is broken. The solenoid  24  de-energizes the armature  64  and the de-energized armature  64  engages the detent  52  to provide minimal resistance to movement of cover  18 , as shown in  FIG. 3 .  
         [0036]     The user must then index the cover  18  to the left as shown in  FIG. 5 . When the cover  18  is indexed to the left to gain access to the battery holder  26 , an electrical circuit or switch  54  is completed when the conductive strip  50  contacts the electrical contacts  22 . If the battery  30  is of insufficient quality, the solenoid  24  will remain de-energized and the armature  64  will further extend and engage positioning notch  46  as shown in  FIG. 5 . At this point, the cover  18  cannot be indexed back to center until the failed battery is replaced by a working battery. Further, the audible alarm device  62  constantly emits the “chirping” sound since the failed battery has still not been replaced. Once the user replaces the failed battery with a working battery, the electrical circuit or switch  54  is completed and the solenoid  24  energizes the armature  64 . Once the armature  64  is energized, it disengages from positioning notch  46 , as shown in  FIG. 6 . The cover  18  may now be indexed back to its working position, shown in  FIG. 3 .  
         [0037]     Additionally, if the failed battery is not replaced with a working battery that will sufficiently power the solenoid  24 , the solenoid  24  will not energize the armature  64  to disengage it from the positioning notch  46  and the cover  18  may not be indexed back to the working position. Further, the audible alarm device  62  still constantly emits the “chirping” sound until the battery is replaced. Thus, the removable battery system  14  of the present invention allows the cover  18  to be moved only if a correctly inserted battery of sufficient charge is installed. The battery is tested by the solenoid to see if it contains sufficient charge to power the detector. If the battery fails, the armature  64  of the solenoid  24  will not retract and release the cover  18 .  
         [0038]     Still further, if the initial batteries inserted are not of sufficient charge, the solenoid will not energize. Thus, the user must initially install working batteries.  
         [0039]     Another embodiment is shown with reference to  FIGS. 8-11 . Removable battery system  66  generally includes a pair of battery compartments  68 ,  70 , a sliding cover  72 , a pair of electrical contacts  74 ,  76 , and a cover solenoid  78 . Battery compartments  68 ,  70  are generally box-like and are sized for receipt of a battery  80 . Battery compartments  68 ,  70  contain polarized electrical contacts  82  and are configured as such so that battery  80  may not be improperly inserted. As shown in  FIG. 8 , it will be appreciated that sliding cover  72  is slidably received within housing  12  as previously discussed with reference to  FIG. 1 .  
         [0040]     Referring now to  FIG. 9 , cover  72  is generally rectangular in nature and includes a tab  84  and a conductive metal strip  86 . Tab  84  is molded to cover  72  at an intermediate location and extends outwardly to facilitate movement of cover  72 . Conductive metal strip  86  is attached to a side  88  of the cover  72 , the importance of which will be further described below. It will be appreciated that conductive metal strip  86  can be made from any suitable conductive material as understood by one of ordinary skill in the art. The conductive metal strip  86  on cover  72  when engaged with the electrical contacts  74 ,  76  form electrical circuits or switches  90 ,  92 , shown in  FIGS. 9-11 , the importance of which will be further described below. Cover solenoid  78  contains an armature  94  as is well know in the art.  
         [0041]     Referring now to  FIGS. 9-11 , a battery  80  has been inserted in a battery compartment  68 . Cover  72  is indexed to the right to enclose battery compartment  70 . The electrical contacts  76  and the conductive metal strip  86 , along with the battery  80  create an electrical circuit or switch  90 . If the inserted battery  80  is of proper charge and electrical circuit complete, the solenoid  78  will energize and the armature  94  will retract, not shown. The cover  72  may then be indexed to the left as shown in  FIG. 10 . Once the cover is indexed to the left, the electric circuit  90  is interrupted and the solenoid will de-energize and the armature  94  will extend. Since the cover  72  is indexed to left and the circuit interrupted, the extended armature  94  prevents the covered battery  80  from being removed. Upon failure of the battery  80 , the smoke detector circuitry  60  indicates a low battery voltage condition. The smoke detector circuitry  60  activates the audible alarm device  62 , which emanates a “chirping” noise to warn of the condition.  
         [0042]     At this point the user must replace the failed battery  80  with a working battery, not shown, in order to eliminate the “chirping”. In this embodiment, the user will simply add the battery, not shown, to the battery compartment  70 . Once the battery, not shown, is added to the battery compartment  70 , the electric circuit or switch  92  comprising the electric contacts  74 , the battery, not shown, and the conductive metal strip  84  is complete. The completed circuit energizes the solenoid  78  and retracts the armature  94 . The cover may be then indexed back to the right. Once the cover is indexed to the right, the electric circuit  90  is interrupted due to failed battery  80 , and the solenoid  78  will de-energize and the armature  94  will extend.  
         [0043]     As stated above, if the failed battery  80  is not replaced with a working battery that will sufficiently power the solenoid  78 , the solenoid  78  will not energize the armature  94  to disengage and the cover  72  may not be moved to expose the failed battery  80 . The cover  72  will remain as shown in  FIG. 10 . Further, the audible alarm device  62  still constantly emits the “chirping” sound until the battery is replaced. Thus, the removable battery system  66  of the second embodiment allows the cover  72  to be moved only if a correctly inserted battery of sufficient charge is installed. The battery is tested by the solenoid to see if it contains sufficient charge to power the detector. If the battery fails, the armature  94  of the solenoid  78  will not retract and release the cover  72 .  
         [0044]     This embodiment provides the same benefits as the previous embodiment without the need for a dual battery system. The “human factor” has been removed, as the cover will not permit the removal of a failed battery until a working battery has been inserted in a battery compartment.  
         [0045]     The present invention has been described in relation to particular embodiments, which are intended in all respects to be illustrative rather than restrictive. Alternative embodiments will become apparent to those skilled in the art to which the present invention pertains without departing from its scope.  
         [0046]     It will be seen from the foregoing that this invention is one well adapted to attain the ends and objects set forth above, and to attain other advantages, which are obvious and inherent in the device. It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and within the scope of the claims. It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described hereinabove. Rather, all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not limiting.