Abstract:
An adaptor ( 10 ) including a sensor ( 18 ), a gimbal housing ( 12 ) having a male connector ( 14 ) at one end and an female connector ( 16 ) at another end, wherein the male connector ( 14 ) is configured to connect with an electrical socket and the female connector ( 16 ) is configured to connect with an electrical device, and a circuit for selectively controlling the electrical device in response to the sensor ( 18 ). The gimbal housing ( 12 ) is adapted to rotate around the male connector ( 14 ) about a first axis and support the sensor ( 18 ) for independent rotation about a second axis perpendicular to the first axis so that the sensor ( 18 ) can be moved to a selectable sensing orientation.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to an adaptor, and in particular, an adaptor for domestic lighting applications having a gimbal mounted detector.  
         [0002]     In the context of this specification, “gimbal” means a device with two mutually perpendicular axes of rotation, thus giving free angular movement in two directions, on which an object may be mounted.  
       BACKGROUND OF THE INVENTION  
       [0003]     In recent years, various automatic switching devices have been marketed, which function to switch lighting on and off, depending on some sensed condition. For example, an ambient light level sensor may be incorporated into the switching device so as to switch on the light when the ambient light falls below a certain level (e.g. when night falls). Alternatively, there may be a motion sensor for detecting motion within a particular field of view of the detector and switching the light on when motion is detected.  
         [0004]     One known motion detector arrangement for switching lighting has a housing which must be fixed in place (e.g high up on an external wall) and must be wired during installation thereof so as to connect into the mains power supply. This arrangement is relatively expensive and requires installation by an electrician. Additionally, the installation is not easily moved once it is fixed in place and wired into the mains power supply.  
         [0005]     U.S. Pat. No. 4,823,051 by Young describes an infra-red actuated control switch assembly. This assembly has a motion detecting capability and is housed within a plug and socket adaptor to be interposed between a light bulb and a socket in normal domestic applications. The sensing system described by Young has a 360° range in the horizontal plane, with two separate sensing fields in a vertical field of view. This arrangement does not, however, allow for the field of view of the motion sensor to be directionally targeted. Thus, in situations where it is not desired to switch the light based on motion in a certain part of the room, the light will nonetheless be undesirably switched on. Thus, the 360° range of the assembly described by Young lacks directional adjustability and may inconveniently switch on when not desired.  
         [0006]     It is desired to provide an adaptor device which is relatively inexpensive, easy to install and remove and has a motion sensing capability which can be directionally targeted, or to at least provide a useful alternative to the prior art.  
         [0007]     The reference to any prior art in this specification is not, and should not be taken as, an acknowledgment or any form of suggestion that that prior art forms part of the common general knowledge in Australia.  
       SUMMARY OF THE INVENTION  
       [0008]     According to the present invention, there is provided an adaptor comprising a gimbal mounted sensor adapted to be interposed between an electrical device and a power supply, wherein power is selectively supplied to the electrical device in response to the sensor.  
         [0009]     The present invention also provides an adaptor comprising: 
        a sensor;     a gimbal housing having a male connector at one end and a female connector at another end, wherein the male connector is configured to connect with an electrical socket and the female connector is configured to connect with an electrical device; and     a circuit for selectively controlling the electrical device in response to the sensor;     wherein the gimbal housing is adapted to rotate around the male connector about a first axis and support the sensor for independent rotation about a second axis perpendicular to the first axis so that the sensor can be moved to a selectable sensing orientation.        
 
         [0014]     Preferably, the sensor comprises one of a motion detector, an infrared detector, a photodetector and a sound detector.  
         [0015]     Advantageously, the male connector and the female connector are respectively provided on opposite ends of the gimbal housing in alignment with the first axis.  
         [0016]     Preferably, the electrical socket is a light socket.  
         [0017]     Advantageously, the electrical device comprises a light source. Most advantageously, the electrical device is a light bulb. Alternatively, the electrical device comprises one of a mobile telephone, a sound alarm, a security device, and a monitoring device. Preferably, the security device comprises a burglar alarm. Preferably, the monitoring device comprises a surveillance camera.  
         [0018]     Preferably, the sensor is substantially spherical in shape and the gimbal housing is substantially annular in shape so that the sensor is supported at least partially inside the gimbal housing between the male connector and the female connector. More preferably, the gimbal housing has one or more openings formed therein to correspond with at least some selectable sensing orientations of the sensor. Most preferably, the one or more openings comprise first and second windows respectively formed in opposite sides of the gimbal mounting between the second axis and the female connector.  
         [0019]     Advantageously, the gimbal housing further comprises a locking mechanism for lockably rotating the gimbal housing about the male connector. More advantageously, the locking mechanism comprises a ratchet wheel and pawl.  
         [0020]     Preferably, the sensor is adapted to rotate less than 360° around the second axis. More preferably, the sensor is adapted to rotate to a maximum of about 350° around the second axis.  
         [0021]     Advantageously, the gimbal housing is adapted to rotate less than 360° around the first axis. More advantageously, the gimbal housing is adapted to rotate to a maximum of about 350° around the first axis.  
         [0022]     The present invention further provides a method for operating an electrical device comprising the steps of: 
        connecting one end of an adaptor to the electrical device and a second end to an electrical socket;     supporting a sensor in a gimbal housing between the ends of the adaptor so that the sensor is rotatable about two mutually orthogonal axes;     moving the sensor to a selectable sensing orientation; and     selectively controlling the electrical device in response to the sensor.        
 
         [0027]     Advantageously, the electrical device comprises a light source. Most advantageously, the electrical device is a light bulb. Alternatively, the electrical device comprises one of a mobile telephone, a sound alarm, a security device, and a monitoring device. Preferably, the security device comprises a burglar alarm. Preferably, the monitoring device comprises a surveillance camera.  
         [0028]     Preferably, the sensor comprises one of a motion detector, an infrared detector, a photodetector and a sound detector. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0029]     Embodiments of the invention will be described in further detail hereinafter, with reference to the drawings, in which:  
         [0030]      FIG. 1  is a front view of an adaptor according to one embodiment of the invention;  
         [0031]      FIG. 2  is a side view and schematic representation of the adaptor of  FIG. 1 ;  
         [0032]      FIG. 3  is a side view and schematic representation of the adaptor of  FIG. 1 , with the motion detector rotated into an alternate position;  
         [0033]      FIGS. 4A, 4B  and  4 C show a plug part of the adaptor, illustrating the configuration of a locking pin and locking plate associated with the plug;  
         [0034]      FIG. 5  is a partial cut-away view of the adaptor;  
         [0035]      FIG. 6  is a front view and schematic diagram of an adaptor of another embodiment of the invention;  
         [0036]      FIG. 7  is a perspective view of an adaptor of another embodiment of the invention; and  
         [0037]      FIG. 8  is a partial cut-away view of the embodiment of  FIG. 7  showing the locking mechanism. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0038]     In this specification, and specifically including the description and drawings, like reference numerals indicate like features, functions or parts, unless otherwise indicated.  
         [0039]     Referring to FIGS.  1  to  3 , there is shown an adaptor  10  having a housing  12  of a generally shallow cylindrical shape. A motion detector  18  (also termed a motion sensor) is located within the cylindrical body of the housing  12  and connected thereto by housing connectors  30 . The housing connectors  30  allow rotation of the motion detector  18  relative to the housing  12  about a lateral (or generally horizontal) axis extending through the housing connectors  30  and the center of the motion detector  18 .  
         [0040]     At a top end of the housing  12  is mounted a top housing part  13  having a plug part  14  connected thereto. The plug part  14  is configured to be inserted into a light socket such as is commonly used for domestic lighting in Australia. The arrangement or configuration by which the plug part  14  engages with a socket may be modified to suit the type of domestic lighting connections prevalent in different countries. For example,  FIG. 6  shows an alternative embodiment of the adaptor having a screw in plug part  64  in place of the plug part  14  of FIGS.  1  to  4 .  
         [0041]     The top housing part  13  may be integrally formed with housing  12  or separately formed and connected thereto by conventional means, such as adhesive or mechanical attachment. The top housing part  13  serves to provide a substructure of the housing  12  within which the plug part  14  may rotate relative to the housing  12  about a longitudinal axis of the adaptor  10 .  
         [0042]     Plug terminals  34  are arranged on the underside of the plug part  14  and concealed within the top housing part  13  for connecting conductors thereto by which power is provided to a light bulb fitted into socket part  16 .  
         [0043]     The top housing part  13  also accommodates a locking pin  26  which engages with a locking plate  22  on the bottom of the plug part  14 . The locking pin  26  moves within a channel in the top housing part  13  and is biased by a spring  27  into a normal extended position in which it engages with the locking plate  22  to prevent rotation of the plug part  14  relative to the housing  12 . This is illustrated in more detail in  FIGS. 4A, 4B  and  4 C. When the locking pin  26  is depressed, compressing the spring  27 , it moves into a retracted position in which it does not engage with the locking plate  22 , thus freeing the plug part  14  to rotate relative to the housing  12 .  
         [0044]     The locking plate  22  has a number of recesses or depressions  24  therein which engage with the locking pin  26  when it is in its extended position. In the exemplary embodiment illustrated in  FIGS. 4A  to  4 C, the locking pin  26  is formed so as to have a base portion formed larger than a top portion. In its extended position, the base portion of the locking pin  26  fits generally into one of the recesses  24  in the locking plate  22 . The locking pin  26  is only allowed to move between its extended and retracted positions and is fixed against movement in the plane of the locking plate  22 , such that in its extended position, the locking pin  26  fits into a recess  24  and prevents rotational movement of the locking plate  22 . In its retracted position, the top part of the locking pin  26  is sufficiently small so that it does not engage with any of the recesses  24 , thus allowing rotational freedom of the locking plate  22 . However, the top part of the locking pin  26  is still formed sufficiently large to prevent rotation of the locking plate  22  beyond about 90° in each direction by interfering with circumferential parts of the locking plate  22  which do not have recesses  24  formed therein. Other arrangements may be employed for fixing the plug part  14  against rotational movement and preventing rotation beyond about 180°.  
         [0045]     On an opposite part of the housing  12  to which the plug part  14  is connected, there is formed a socket part  16  for receiving a light bulb (not shown). The socket part  16  is adapted to receive light bulbs having a plug configuration corresponding to that of plug part  14 .  
         [0046]     Windows  20  are provided in parts of the housing  12  adjacent the socket part  16  and extending generally between the socket part  16  and those parts of the housing  12  adjacent the housing connectors  30 . The windows  20  are arranged to enable transmission of electromagnetic radiation to and from a sensor screen  19  of the motion detector  18  when the motion detector is pivoted so as to point generally downwardly (such as is shown in  FIG. 3 ). The windows  20  are preferably holes, but may alternatively contain some kind of transmissive filter or polarising material. As shown in  FIG. 3 , the windows  20  are shaped so as to allow a sensing field of the motion detector  18  to extend therethrough when the motion detector  18  is in a vertically downwardly directed orientation. In this position, while the socket part  16  obscures part of the sensing field of the motion detector  18 , much of the sensing field will still extend vertically and laterally outward and downward of the adaptor  10 . This positional arrangement of the motion detector  18 , in combination with the configuration of the windows  20  and the housing  12 , allows for the adaptor  10  to be located in a light fixture in a hallway, such that the sensing field of the motion sensor  18  can extend in either direction down the hallway. Additionally, the rotational adjustability of the plug part  14  relative to the housing  12  facilitates simple adjustment of the adaptor  10  for optimal orientation thereof with respect to the hallway. If not for the rotational adjustability of the plug part  14  relative to the housing  12 , the adaptor  10 , once installed in the light socket, may not be able to be positioned so as to extend the sensing field in both directions down the hallway, for example because of the fixed orientation of the socket in which the adaptor  10  is installed.  
         [0047]     The motion sensor  18  depicted in the drawings is preferably of a roughly elliptoid or spherical shape with the sensor screen  19  disposed on an outer portion thereof generally in the direction of a lateral axis of the housing  12 . The inner workings of the motion sensor  18  do not form part of this invention. A motion sensor  18  for use in a preferred form of the adaptor  10  may be one that is commercially available. Importantly, the motion sensor  18  must be able to receive and switch mains power and to itself run on mains power. Preferably, the motion sensor  18  has adjustable inputs for adjusting the time after which the motion detector switches off the light following the absence of any sensed motion. Also preferably, the motion sensor  18  may have a manual input adjustment for varying the ambient light level at which the sensor is enabled or disabled from operating.  
         [0048]     Shown in  FIG. 2  is an arrangement in which the motion sensor  18  is positioned so that its sensor field is directed generally laterally. The direction of the sensor field may be altered by pivoting the motion sensor  18  about the lateral axis through the housing connectors  30 , for example so as to direct the sensing field more downwardly than is depicted in  FIG. 2 .  
         [0049]     Illustrated in  FIGS. 2, 3  and  5  are ground conductors  32   a,    32   b  and active conductors,  33   a  and  33   b  for powering the motion detector  18  to thus selectively switch power to a light fitted into socket part  16 . The conductors are connected within the housing  12 . Ground and active conductors  32   a  and  33   a,  respectively, are connected to plug terminals  34  and to the motion detector  18  (through one of the housing connectors  30 ). An active conductor  33   b  is also connected to motion detector  18  and to a socket terminal  36  associated with socket part  16 , such that when the motion detector  18  senses motion, it switches active power to active conductor  33   b,  which is supplied to the light globe in socket part  16 . A ground conductor  32   b  is connected between a ground terminal of the socket terminals  36  and a ground terminal of plug terminals  34  for completion of the circuit through the light globe.  
         [0050]     In the wiring arrangement shown in the drawings there is no provision for allowing rotation of the plug part  14  or motion sensor  18  without twisting the conductors connected thereto. In an alternative embodiment (not shown) a form of intermediate electrical connector may be used to minimise the twisting effect on the conductors. In a further alternative, the plug terminals  34  may be arranged to allow for pivotal rotation of the plug part  14  without undue twisting of the conductors connected thereto and similarly with electrical connections to the motion detector  18 .  
         [0051]      FIG. 5  further illustrates the arrangement of the conductors  32   a, b  and  33   a, b  within one side of the housing  12 . Also shown in  FIG. 5  are housing and connector bosses  29 ,  31  associated with each housing connector  30 . The housing boss  29  is fixed to the housing  12 , whereas the connector boss  31  rotates about the lateral axis along with rotation of the motion detector  18 . The connector boss  31  is arranged to abut the housing boss  29  at the extremities of permissible rotation of the motion detector  18  relative to the housing  12 , so as to limit the rotational freedom thereof to a maximum of about 350°. Preferably, the housing boss  29  and connector boss  31  are arranged so as to allow for rotation of the motion sensor  18  from the near vertical on one side of the housing  12 , down through the position shown in  FIG. 3  and up through to the near vertical on the other side of the housing  12 , but not so as to allow rotation of more than about 350°. If excessive rotation were allowed, this may exert undue twisting stress on the conductors connected through housing connector  30 . In an alternative embodiment (not shown), if an intermediate connector or other means for preventing excessive twisting stress on the conductors is employed, rotation of the motion detector  18  relative to the housing  12  in excess of 350° may be allowed, in which case housing and connector bosses  29  and  31  are not required.  
         [0052]      FIG. 6  illustrates an alternative embodiment of the adaptor, designated by reference numeral  60 . This embodiment differs from previously described embodiments only in so far as the plug and socket connections are concerned. In this embodiment, a plug part  64  is provided which allows for a screw-in connection to a socket such as those which are common in North America. A corresponding socket part  66  is provided on an opposite part of the housing  12  for receiving a screw-in light bulb having a corresponding plug form to that of plug part  64 .  
         [0053]      FIGS. 7 and 8  show a preferred embodiment of the adaptor, designated by reference numeral  100 . This embodiment differs from previously described embodiments in its external appearance and locking mechanism  102 . As shown in  FIG. 8 , the locking mechanism  102  comprises a ratchet wheel  104  and pawl (or locking pin)  26 . The ratchet wheel  104  and pawl  26  operate in a conventional manner to lockably rotate the annular housing  12  about the male connector (or plug part)  14 . The annular housing  12  is lockably rotatable about the male connector  14  up to a maximum of about  350 °. The sensor  18  is similarly rotatable to a maximum of about 350°.  
         [0054]     It should be noted that the present invention is not limited to the particular embodiments described above, but can be implemented using different combinations of conventional electrical connections, sensors and electrical devices.  
         [0055]     The male connector of the adaptor of the present invention is not limited to being connectable with conventional light fittings, but may also be configured to connect with conventional electrical fittings, such as wall mounted electrical sockets.  
         [0056]     The sensor used in the adaptor of the present invention is not limited to a motion detector, but may also be implemented using one or more of an infrared detector, a photodetector and a sound detector.  
         [0057]     The adaptor of the present invention is not limited to connect with and control light sources, but may also be implemented to connect with and control other electrical devices such as mobile telephones or sound alarms. In these embodiments, the female connector of the adaptor may be configured to connect with a mobile telephone or sound alarm. For example, embodiments of the present invention may use the sensor to selectively control a