Abstract:
An alarm system for reminding a driver of the earlier placement of a child in the backseat of a vehicle usable with both a one piece car seat and a two piece car seat comprised of a carrier and base includes in a first embodiment a rear sensor, driver door opening sensor, a control unit, alarm means, and deactivation switch wherein the opening of a rear door activates and arms the system automatically so consequently the alarm means is energized and activated anytime thereafter when the driver opens their door, thus reminding the driver when they are exiting the vehicle of the child in the back. The driver then deactivates the system manually. In another embodiment applied to a child&#39;s two piece car seat includes a car seat occupancy state detector, driver door opening sensor, a control unit, and alarm means, wherein the car seat occupancy state detector is comprised of split components of actuator and sensor which are placed on the carrier and base respectively, thus allowing the user to remove the carrier without needing to remove or disconnect some component of the system first from the carrier and allowing a manufacture to avoid using wireless technology as the means to communicate a signal from the car seat occupancy state detector to the central control unit.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims, the benefit of Provisional Patent Application 61/863,161 filed on Aug. 7, 2013 and Provisional Patent Application 61/945,426 filed on Feb. 27, 2014 by the present inventor, which is incorporated by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    This invention relates to devices intended to remind or alert parents and caregivers that a child is occupying the back seat of a car or car seat in the back seat of a car when exiting or after having left the vehicle so that the child is not inadvertently forgotten and left behind. Nearly all prior art directed at solving this problem use some unique combination of five elements or components. These are, 
         [0003]    First, a means to detect that a child has been placed in the backseat or is present in their car seat. This component functions to arm the system, activating or “waking up” it up upon sensing the child has been placed in the back. Second is a means to detect the driver is exiting or otherwise not present in the vehicle. This component functions to trigger the third component, the alarm means, when the fourth component, a control unit, receives a signal from the child in car detector indicating the child is in the car but at the same time a signal from the driver sensor that the driver is exiting or otherwise absent. In some simpler designs however, there is no control unit and the device is based on simple closing of circuits. The last component is an electrical connection means between the four core components of child in car detector, driver sensor, control unit, and alarm so they can send and receive signals as necessary. Generally speaking, the electrical connection means seen in prior art is either hardwiring the components together or using wireless means such as a RE transmitter and receiver, infrared, or blue tooth technology. 
         [0004]    For example, U.S. Pat. No. 7,012,533 to Younse uses what it refers to as a “built in car seat cushion pressure switch means” to detect the child in a one piece car seat, a “door switch” that senses both the opened state and closed state of the driver&#39;s door, an internal alarm within the cabin of the vehicle, a micro-controller unit, and it also supplements the system with a temperature sensor in communication with an outside alarm as a backup to the internal alarm. It teaches hard wiring all the components together. 
         [0005]    U.S. Pat. No. 7,106,207 to Marchan uses functionally a momentary switch which is refers to as a “contact” switch built into a one piece child&#39;s car seat to detect that the child&#39;s car seat is occupied, a switch which it refers to as a “push button” switch to detect the opened state and the closed state of the driver&#39;s door and which is apparently built into the car door, and shows the components being hardwired together. It has no control unit. When both circuits are closed simultaneously, a circuit to the alarm is completed resulting in the alarm being energized. The alarm is therefore limited to one pattern, sound, and volume. 
         [0006]    Patent Application US 2007/0268119A1 by Cran &amp; Cran, shows in its primary embodiment a combination of a “weight sensor being operable for sensing weight applied to a seat and generating a corresponding weight reading” (apparently to ensure that the alarm is not sounded by the weight of the buckles, cushions, or the seat itself if placed under the seat rather than where the child rests), a magnetically actuated switch for detecting the opening of a car door, a control unit, and a RF transmitter for sending the signal from the weight sensor to the control unit that a child is in the car seat. However, it also states that the device in various embodiments can have the components hardwired together as well and the weight sensor can be a removable pad or built into the car seat itself. 
         [0007]    Devices like the first two above in which the components are hardwired together enjoy the advantage of less susceptibility to outside interference in comparison to devices which use wireless technology to send and receive signals. They can also be designed wherein they are only energized when the child is in the car seat, thus resulting in much longer battery life or without need of an electrical connection to the car. On the other hand, strictly hardwired designs like these examples have one major disadvantage in that they are not practically usable with 2 piece car seats which consist of a base and a removable, portable carrier which the parent takes the child in and out of the car with. Even if the child detector means is some kind of weight sensor pad that can be taken off the seat, if it is hardwired to the rest of the system, the parent cannot easily take the carrier out of the car unless they are willing to remove the pad each time they take the child out of the car and then put in back in when they return. 
         [0008]    Devices employing wireless communication to communicate the signal from the child detector means to the control unit of course have the advantage of being able to be used in 2 piece car seats but at the same time, can manifest another set of issues. For example, in a study published by the Children&#39;s Hospital of Philadelphia sponsored by the NHTSA in 2012 titled “Reducing the Potential for Heat Stroke to Children in Parked Motor Vehicles: Evaluation of Reminder Technology”, three devices which communicated wirelessly to a key fob were evaluated in actual field tests. It found in the test runs that the devices gave off “false alarms” while driving even though of course the parent was right in the car with the child, presumably as stray radio waves caused the alarm to be falsely triggered. In addition, the study authors found that the devices components “ . . . were erratic in staying synched with the key fob. The movement of the vehicle along with the motion of the child in the child restraint led to the devices commonly alternating between synchronized and unsynchronized states”. In addition, two of the three products used a weight sensor pad to detect the child. The authors notes “The two pad devices often required adjusting the position of the child to get the device to arm when evaluated statically and in some cases, we were unable to arm the device at all”. In other words, the parent had to wiggle and shift the child around to get the pad to pick up on the child. 
       BRIEF SUMMARY OF THE INVENTION 
       [0009]    It is the objective of this invention to provide a child in vehicle reminder alarm system that is usable with both a one piece car seat as well as a two piece car seat comprised of a carrier and base but without resorting to wireless technology to communicate the signal from the child detector component to the control unit. For the purposes of this Specification and the appended Claims, an alarm system usable with both a one piece car seat as well as a two piece car seat comprised of a carrier and a base shall be defined to mean an alarm system which if adopted or applied to a two piece car seat does not require the user to detach, remove, replace, disconnect, etc. some component of the system before removing the carrier from the car. 
         [0010]    The invention employs two underlying inventive concepts to achieve the above objective. 
         [0011]    In the first embodiment, rather than employing some means to directly detect that the child is occupying the car seat, the opening of a rear door is detected as a proxy to infer that a child has been placed in the back. In the second embodiment, the concept is to split the car seat occupancy state detector into two components—an actuator piece moved into position by the placement of the child into the carrier and a sensor which is triggerable by the actuator and locating or building in the actuator on the carrier and the sensor on the base. With this split arrangement, the parent can pick up and remove the carrier from the base but when they return and place the carrier back on its base with the child in the carried, the actuator triggers the sensor located on the base. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0012]      FIG. 1  shows a diagram of the electrical components. 
           [0013]      FIG. 2  shows a perspective view of my invention in its first embodiment as it is contemplated to be installed in a four door vehicle. Please note that although the vehicle depicted in  FIG. 2  is one with a swinging rear passenger door typical of a four door sedan, the same layout could be used just as easily with a vehicle with a sliding rear door such as that found on a mini van. 
           [0014]      FIG. 3  summarizes the operating logic. 
           [0015]      FIG. 4  shows a schematic concept diagram to illustrate how my invention would be installed in a vehicle with two doors. 
           [0016]      FIG. 5  shows one possible configuration for a second embodiment of my invention as applied to a two piece car seat comprised of a carrier and base. 
           [0017]      FIG. 6  shows another possible configuration for the second embodiment if built into the carrier and base. 
           [0018]      FIG. 7  shows the same configuration for the second embodiment if built in the carrier and base depicted in  FIG. 5  with the carrier in position on its base. 
           [0019]      FIG. 8  shows a one possible configuration for the second embodiment if structured as an aftermarket part. 
           [0020]      FIG. 9  shows another possible configuration for the second embodiment if structured as an aftermarket part. 
       
    
    
     DETAILED DESCRIPTION OF INVENTION 
       [0021]    As can be seen in  FIG. 1 , provided is an alarm system  100  comprised of a control unit  1 . 0 , an alarm means  2 . 0 , a power source  3 . 0 , all of which are contained and integrated into a protective case  4 . 0  (not show in  FIG. 1 ), at least one rear passenger area accessed sensor  5 . 0 , a driver&#39;s door sensor  6 . 0 , and at least one deactivation switch  7 . 0 . 
         [0022]    The alarm means  2 . 0 , power source  3 . 0 , rear passenger area accessed sensor  5 . 0 , driver&#39;s door sensor  6 . 0 , and deactivation switch  7 . 0  are all electrically connected to control unit  1 . 0 . Control unit  1 . 0  is configured to receive inputs or electrical signals from the rear passenger area accessed sensor  5 . 0 , the driver&#39;s door sensor  6 . 0 , and deactivation switch  7 . 0  and send outputs or electrical signals to the alarm means  2 . 0  which is capable of generating audible or visible output to catch the attention of the parent/driver. In one example embodiment depicted in  FIG. 1 , the alarm means  2 . 0  is a speaker  2   a  with lead wires  2   b,  the power source  3 . 0  is a battery or batteries, the rear passenger area accessed sensor  5 . 0  is a rear reed switch  5   a  with leads  5   b  paired with a rear magnet  5   c,  and the driver&#39;s door sensor  6 . 0  is a front reed switch  6   a  with leads  6   b  paired with a front magnet  6   c.  Rear reed switch  5   a  and driver&#39;s door reed switch  6   a  function as normally closed type switches. Deactivation switch  7 . 0  is provided and electrically connected to control unit  1 . 0  by leads  7   a  to send inputs or signals to control unit  1 . 0  and in this example are of the “touch pad” type commonly found in enhanced children&#39;s story books that play animal sounds, etc when tapped. 
         [0023]      FIG. 2  shows the way the first embodiment of my invention is to be installed in a four door vehicle, such vehicles having a rear passenger door  8 . 0 , a center roof support column  9 . 0  (or the “B Pillar” as it is referred to in the auto industry), and a driver&#39;s door  10 . 0 . As can be seen, the protective case  4 . 0  housing the control unit  1 . 0 , alarm means  2 . 0 , and power source  3 . 0  is attached by any suitable means such as tape, glue, hook and loop tape, adhesive strips, double sided foam, etc., to the face of the central roof support column  9 . 0  so that it is secured from being jostled when the car is moving. Rear reed switch  5   a  is attached in a similar manner to the outside edge of the central roof support column  9 . 0  nearest rear door  8 . 0 . Driver&#39;s door reed switch  6   a  is attached to the outside edge of central roof support column  9 . 0  on the outside edge nearest driver&#39;s door  10 . 0 . Rear magnet  5   c  and front magnet  6   c  are attached in a similar manner to the outside edge of their respective rear and driver doors nearest the central roof support column  9 . 0  in alignment with their respective reed switches  5   a  and  6   a,  positioned and oriented such so that the gap between the components is sufficiently narrow to result in reed switches  5   a  and  6   a  being triggered upon the opening of their respective doors. Although not depicted in  FIG. 1  and not necessary for the functioning of alarm system  100 , a passenger side rear sensor  5   a ′, passenger side rear magnet  5   c ′, and passenger side deactivation switch  7 . 0 ′ would normally be provided and attached in the same configuration and manner as just described above to the passenger side central roof support column and passenger side rear door so that both rear doors would be monitored for opening and the driver/parent could arm and deactivate alarm system  1 . 0  from either side of the vehicle. The wire leads for the passenger side rear sensor  5   a ′and passenger side deactivation switch  7 . 0 ′ would be placed under the carpet mats or below the front seats to keep them protected and from underfoot. In the case of a four door vehicle deactivation switch  7 . 0  is attached to the top most edge of the interior door panel of rear door  8 . 0  at the bottom of the window by any suitable means such as tape, glue, hook and loop tape, adhesive strips, double sided foam, etc so as to be within arm&#39;s reach and conveniently accessible to the parent when they open the rear door. In the case of a mini van with sliding rear passenger door, it is mounted to the central roof support column  9 . 0  at a convenient height. 
         [0024]    In one possible programming configuration, the control unit  1 . 0  is programmed to play or trigger a plurality of sounds, tones, or voiced messages by energizing speaker  2   a.  These sounds are played or triggered in accordance with the operating logic depicted in the flow chart of  FIG. 3 . In one possible example operating pattern as depicted in  FIG. 3 , the tones or sounds includes a “confirm tone”, an “alarm tone”, and an “off message”. All of these tones or messages are programmed to play at a certain volume and for a predetermined number of times or length of time with any number of patterns possible but it will be appreciated that the best pattern will balance the need to get the driver&#39;s/parent&#39;s attention with the need not to be irritating to the adult driver or startle the child when going off. 
         [0025]    Referring to  FIG. 3 , when rear sensor  5   a  is triggered by the opening of a rear door, the alarm system  100  is put into “active/armed” mode by the controller  1 . 0  if it is not already in such a mode. Upon the alarm system  100  going into “active/armed” mode, the control unit  1 . 0  sets the mode of the driver&#39;s door sensor  6 . 0  to “active/armed” thereby arming it and at the same time, triggers the “confirm tone” so that the driver/parent knows that the system has been armed. With driver&#39;s door sensor  6 . 0  now in “active/armed” mode when the parent then opens their driver door  10 . 0  to get in, the driver&#39;s door sensor  6 . 0  is triggered and in turn the control unit  1 . 0  plays the “alarm tone” a limited number of times or for a short length of time, e.g, 2× or 5 seconds, as programmed. The playing of the “alarm tone” in this instance where the driver is getting into the vehicle and not exiting serves not to “remind” but to reconfirm that the alarm system  100  is on and working properly before the driver leaves. If the “alarm tone” should not play when the driver is getting in, this will serve as a useful warning that something is wrong, e.g., the front magnet  6   c  has fallen off, and investigation is needed. After driving and arriving at their destination when the driver/parent opens their driver door, driver&#39;s door sensor  6 . 0  is triggered again resulting in the “alarm tone” sounding, thus reminding the driver that there is still a passenger in the rear. Should this be the true final destination, i.e, not getting out mid-trip to get gas, the parent will retrieve the child and upon opening one of the rear doors to do so, the “alarm tone” will be triggered again. In this case, this will serve to prompt the parent/driver to press the deactivation switch  7 . 0  which when the parent does, causes the control unit  1 . 0  to play the “the alarm is off” voice message and put alarm system  1 . 0  into “sleep” mode. If the parent exits and it is not the final destination but just a temporary stop such as to get gas the alarm will be activated but since the duration or number of times the alarm tone plays is programmed to be limited, the parent does not necessarily need to deactivate it as it should not be irritating to the child or other passengers remaining in the car. 
         [0026]    The placement and installation of my invention as illustrated in  FIG. 2  is appropriate for four door vehicles. However as shown in FIG.  4 &#39;s schematic diagram, the installation would be slightly different for a two door vehicle featuring a backseat  12  and a driver&#39;s seat  11 . 0 , comprised of seat base  11   a  and moveable seat back  11   b  which, as is well known, the driver must flip forward to gain access to backseat  12  so as to be able to place an infant car seat carrier  20  (not shown in  FIG. 4 ) in the backseat. The protective case  4 . 0  housing the central control unit  1 . 0 , alarm means  2 . 0 , and power source  3 . 0  is attached to any suitable spot on the interior wall of the vehicle flanking the backseat as depicted in  FIG. 4  or alternatively, attached to seat base  11   a.  Rear reed switch  5   a  is attached to seat base  11   a  in either case. Rear magnet  5   c  is attached to seat back  11   b  in close enough proximity to rear reed switch  5   a  and oriented such so as to trigger rear reed switch  5   a  when moved by the parent flipping the seat back forward. Attached so, when the parent/driver flips their seat back  11   b  forward, rear magnet  5   c  moves away from rear reed switch  5   a  resulting in rear reed switch  5   a  being triggered and arming/activating the alarm system  100 . Front reed switch  6   a  is attached on the edge of the interior wall facing backseat  12  that is nearest driver&#39;s door  10 . 0  and front magnet  6   c  is attached to the driver&#39;s door  10 . 0 , the two components installed in close enough proximity and oriented such so that front reed switch  6   a  is triggered when the parent/driver opens driver&#39;s door  10 . 0 . Deactivation switch  7 . 0  is mounted on seat back  11   b  or other easily reachable spot such as on the vehicle&#39;s interior wall facing backseat  12  or on the car seat base  23  itself. 
         [0027]    The rear passenger area accessed sensor  5 . 0  and driver&#39;s door sensor  6 . 0  could be means other than magnetic reed switches, such as Halls Effect sensors, etc. Besides batteries, the power source  2 . 0  could be an electrical connection configured to engage a vehicle&#39;s DC power source. 
       First Embodiment 
     Detailed Description 
       [0028]    In this embodiment, the components are the same as the first embodiment except that the rear passenger area accessed sensor  5 . 0  and deactivation switch  7 . 0  are replaced by a car seat occupancy state detector  21 . 0 . In this embodiment, an alarm system that works both with a one piece car seat as well as a two piece car seat is afforded by car seat occupancy state detector  21 . 0  which is comprised of at least two split components—a occupancy sensor actuator  21   a  and a occupancy sensor  21   b,  When this system is applied to a two piece car seat the former is built into or located on the carrier piece and the latter is located on the base, thus making the carrier easily removable but allowing for the occupancy sensor  21   b  to be hardwired. 
         [0029]    Shown in  FIGS. 5-9  are four ways occupancy sensor actuator  21   a  (labeled  21   a   1 ,  21   a   2 ,  21   a   3 ,  21   a   4  in the Figs.) can be structured in cooperation with two types of occupancy sensors  21   b,  those being a magnetically actuated switch such as a reed switch  21   b   1  shown in the figures or Halls Effect sensor and a momentary switch  21   b   2 . 
         [0030]      FIGS. 5 ,  6 , and  7  show possible structures and means if the occupancy sensor actuator  21   a  is built into the carrier  20 , say by a manufacturer who elected to adopt this alarm system for their line of two piece car seats and also wanted the same alarm system to work with their line of one piece of car seats. 
         [0031]      FIGS. 8 and 9  show a possible structure for car seat occupancy state detector  21 . 0  where a manufacture could “add on” alarm system  100  to their existing line of car seats by simply sewing or otherwise attaching a component to a car seat cover  22  as will be illustrated. Likewise a consumer could do the same for a car seat they already own. 
         [0032]    Note that in  FIGS. 5-9  the side walls of carrier  20  and base  23  are cut away for ease of viewing. 
         [0033]    The first suggested way to structure occupancy sensor actuator  21   a  is shown in  FIG. 5  and may be summed up as “a seat flap configured with a magnet and built into the carrier”. In this example, car seat carrier  20  is designed with a built in seat flap  21   a   1 . Affixed to the underside of seat flap  21   a   1  and to the car seat carrier  20  are compression springs  21   d  and  21   e . In addition, magnet  21   c  is embedded into seat flap  21   a   1 . Also seen is carrier base  23  upon which magnetic reed switch  21   b   1 —is attached. Magnetic reed switch  21   b   1  functions as a normally open type switch in all cases of this second embodiment of alarm system  100 . 
         [0034]    In the example configuration for seat flap  21   a   1  shown in the figure, seat flap  21   a   1  presents a profile when viewed from the lateral side as a rectangular plane with a three quarters round rod shape along one edge with the upper plane of the seat flap  21   a   1  tangent to the three quarters round rod shape and the lower plane bisecting the center point of the rod shape. The rod shape functions as an axis about which seat flap  21   a   1  rotates. As can be seen in  FIG. 5 , the portion of the car seat carrier constituting where the baby&#39;s body rests upon (which for purposes of this description shall be referred to as the “carrier floor”  20   a ) is formed with an indenture  20   b  in its profile that matches up with the profile of the underside of seat flap  21   a   1 . Its form also incorporates cup holder like spring recesses  20   c  and  20   d  into which springs  21   d  and  21   e  can compress and fully recede into. 
         [0035]    When no child is in the carrier  20  seat flap  21   a   1  is biased by compression springs  21   d  and  21   e  to rotate about its rod like axis portion to extend upwardly and away from carrier floor  20   a  so magnet  21   c  is in a non-actuating or non-triggering position. Resilient shape retaining deformable foam, elastic band, or weights could also be employed to accomplish the same upward urging function. However when a child is placed in the car seat carrier  20 , the intrusion of the child&#39;s body causes seat flap  21   a   1  to rotate downwards and nest in indenture  20   b  as shown in  FIG. 6  wherein it more or less lies flush with the carrier floor  20   a  so that a substantially smooth surface is provided for the child&#39;s comfort and it is positioned into an actuating state. Conversely, base  23  is formed and molded so as to provide a place where reed sensor  21   b   1  is positioned within triggering proximity when seat flap  21   a   1  and its embedded magnet  21   c  is in actuating position. Thus if the parent places the child into carrier  20  and then places the carrier with child onto base  23  magnetic reed switch  21   b   1  is actuated and alarm system  100  is put in active/armed mode. Conversely if the child or the carrier with child still inside is removed, alarm, system  100  is put in sleep mode. 
         [0036]    Though not shown in  FIGS. 5 &amp; 6 , it is standard practice for all infant car seats to come with a form fitting seat cover  22  (see  FIG. 7 ) that is tailored to fit over the carrier so as to provide a soft surface for the child to be laid upon. This being the case, it is understood that the seat cover would be tailored as necessary to accommodate and not hinder the upward and downward movement of seat flap  21   a   1 . 
         [0037]    The second suggested way to structure occupancy sensor actuator  21   a  is shown in  FIG. 7  and may be summed up as “a seat flap configured with no magnet and built into the carrier”. It is mean to be used in cooperation with a momentary push button type switch  21   b   2 . in this case, carrier  20  is provided with a hole  20   e  through which the top portion of momentary push button type switch  21   b   2  protrudes above the plane of seat carrier floor  20   a  and upon which seat flap  21   a   2  rests in a non-actuating manner. Seat flap  21   a   2  is identical to seat flap  21   a   1  except it has no magnet embedded or attached to it. When the child is placed in carrier  20 , seat flap  21   a   2  is moved downward into actuating position and momentary push button switch  21   b   2  actuated. 
         [0038]    The third possible way to structure occupancy sensor actuator  21   a  can be described as “a seat flap configured with a magnet and attachable to a seat cover of a car seat”. This structure is one that affords a manufacturer or a consumer the ability to add alarm system  100  to their existing line of car seats or one which the consumer already owns. It is comprised of a resilient board  21   f  covered and encased within a cavity formed by tailored padded cover  21   g  forming an “upper” portion and leaving a “lower” portion which is affixed to the seat cover using any suitable attachment means such as glue, sewing, adhesive strips, hook &amp; loop tape, etc so that the “upper” portion encasing resilient board  21   f  is free to swing up and away or down and towards car seat base  23  to lay substantially flat on cover  22  when fully depressed. Magnet  21   c  is embedded within resilient board  21   f.  Shape retaining deformable foam cylinder  21   h,  made of mattress foam or packing foam to give an example, functions as a spring, urging the “upper” portion away from the base  23 . A spring, elastic band, or weights could also be employed to accomplish the same upward urging function 
         [0039]    Magnetic reed sensor  21   b   1  is attached to base  23  or if necessary, a spacer  24  which in turn is attached to base  23 . To explain the function of spacer  24 , different manufacture&#39;s car seat carriers and their matching bases will exhibit varying sizes of gaps between underside of the car seat carrier  21  and the base  23 , including situations wherein the gap is too wide for the desired triggering or actuating action to occur if reed switch  21   b   1  is attached directly to base  23 . To accommodate a variety of such situations and bring rear reed switch  21   b   1  to its maximum possible closeness to the underside of car seat carrier  20 , i.e., flush against the underside, spacer  24  is provided which can be seen in  FIG. 8 . Such a spacer  24  would most advantageously be of a deformable but shape retaining material such as mattress or packing foam, sponge, clay, or a Play-doh like substance. If made of clay for example, in application the user would form an overly large block of the spacer material, place it on the appropriate location of base  23  that corresponds to where magnet  21   c  will be positioned above it when occupancy sensor actuator  21   a   3  is depressed, imbed reed sensor  21   b   1  slightly on top of the ball of material, and then place car seat carrier  20  onto its base  23 . This action will result in the reed switch being embedded into and held in place by the clay material of spacer  24  while at the same time lying flush against the underside of carrier  20 . Alternatively, if made of foam, the shape and form of spacer  24  could be molded with an open or closed recess at the top conforming tightly to the shape of reed switch  21   b   1  and its lead wires into which it would be inserted and held therein either by friction fit or with adhesive. Space  24  could also be a spring. 
         [0040]    A last simplified design of occupancy sensor actuator  21   a  is shown in  FIG. 9 . It is comprised of a foam block  21   a   4  made of resilient shape retaining deformable foam or as it is sometime more commonly referred to, mattress or packing foam, with magnet  21   c.  Magnet  21   c  is embedded within foam block  21   a   4  towards the top end. Adhesive strips (not shown in  FIG. 9 ) are provided on its underside for affixing it to seat cover  22  or the same could be achieved by shaping foam block  21   a   4  to friction fit into the space against the walls of carrier  20 . Alternatively, foam block  21   a   4  is placed underneath seat cover  22  and adhered directly onto base  23  wherein a lump is formed under seat cover  22 . In either case, the body of the child when placed in the car seat depresses and compresses foam block  21   a   4  thereby bringing magnet  21   c  into triggering proximity to reed switch  21   b   1 .